A Orn Guidance Statement

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AORN Guidance Statement:

Safe Patient Handling and

Movement in the

Perioperative Setting


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AORN Guidance Statement:

Safe Patient Handling and Movementin the Perioperative Setting

Copyright 2007

AORN, Inc.2170 South Parker Road, Suite 300

Denver, CO 80231www.aorn.org

Clinical Editor: Carol Petersen, RN, BSN, MAOM, CNOR

Editorial Manager: Deb RenoLayout Assistant: Lynn Hayne

Copy Editor: Linda DeLiaProduction Manager: Terry Isaacs

All rights reserved. No part of this publication may be reproduced or transmittedin any form or by any means, electronic or mechanical, including photocopying,

recording, or any information storage and retrieval system, without writtenpermission from AORN. Permission may be sought directly from AORN Publications,

located in Denver, Colorado (USA), by contacting the Editorial Department,phone 303-755-6304 ext. 232; fax 303-750-3441; e-mail [email protected].

ISBN 1-888460-59-8 Printed in USA


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Introduction ..........................................................................................................4

Development of the AORN Guidance Statement:Safe Patient Handling and Movement in the Perioperative Setting................................5

AORN Guidance Statement: Safe Patient Handling andMovement in the Perioperative SettingDescription of the problem ..................................................................................11Task force members ..............................................................................................13Description of the process ....................................................................................13

Ergonomic ToolsErgonomic Tool #1: Lateral transfer from stretcher to and from the OR bed ..........14

Ergonomic Tool #2:Positioning/repositioning the patient on theOR bed into and from the supine position ........................................................17

Ergonomic Tool #3: Lifting and holding legs, arms, and headfor prepping in a perioperative setting ..............................................................18

Ergonomic Tool #4: Prolonged standing ................................................................19

Ergonomic Tool #5: Retraction ..............................................................................21

Ergonomic Tool #6: Lifting and carrying supplies and equipment ..........................21

Ergonomic Tool #7: Pushing, pulling, and moving equipment on wheels ................24

Tables

Table 1: Data used to calculate the NIOSH lifting index values for typical items ......23

Table 2: Measured push forces for operating room equipment ..............................25

Table 3: Push force limits ......................................................................................27

Table 4: Recommended weight limit ....................................................................28

Table 5: Frequency multipliers ..............................................................................29

Table 6: Coupling multiplier..................................................................................30

Other Background MaterialsRevised NIOSH Lifting Equation ..........................................................................27Glossary................................................................................................................30References ............................................................................................................31

Acknowledgments ................................................................................................33

Index ....................................................................................................................35

Table of Contents


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Safe Patient Handling and Movement in the Perioperative Setting4

High-risk patient handling tasks can lead towork-related musculoskeletal disorders(MSDs) for perioperative registered nurses

and other members of the perioperative team. Thesedisorders often have serious consequences. Staffmembers who experience pain and fatigue are lessproductive, more likely to make mistakes, and moresusceptible to further injury. Nurses who are injured,

or who are afraid of being injured, may seek otheremployment or even leave the profession. These fac-tors may contribute to staffing shortages, highturnover, and increased costs for health care facilities.

In 2005, the Workplace Safety Task Force wascharged by AORN President Sharon McNamara,RN, MS, CNOR, to prepare a guidance documentto support ergonomically healthy workplaces. Thegoals of the task force were to identify high-risktasks performed in the perioperative area and todevelop evidence-based solutions to minimize therisk of MSDs among perioperative team members.

Task force members included representatives fromAORN; the National Institute for OccupationalSafety and Health (NIOSH); the Patient Safety Cen-ter of Inquiry at the James A. Haley VeteransAdministration Medical Center (VMAC) in Tampa,Fla; and the American Nurses Association.

Seven clinical tools, or algorithms, were devel-oped by the task force to guide ergonomic work-place safety in the perioperative setting. These clin-ical tools incorporate current ergonomic safetyconcepts, scientific evidence, and the use of tech-nology such as safe patient handling equipment.The seven clinical tools, the rationale for theirdevelopment, and the calculations supporting

them were combined into a single document, theAORN guidance statement: Safe patient handlingand movement in the perioperative setting.

The guidance statement is reprinted in itsentirety in this publication. Also included is anoriginal article detailing the development of theguidance statement introduces the work of the taskforce and the process used to analyze the problemof MSDs in the perioperative setting. Throughoutthe next year, other articles will be published in theAORN Journal to explain the use of the clinicaltools and provide assistance in implementing them

in practice. AORN believes that increased knowl-edge and widespread acceptance of safeergonomic practices will help to promote a saferperioperative work environment and protect peri-operative team membersas well as theirpatientsfrom work-related injury.

Introduction to Safe Patient Handling andMovement in the Perioperative Setting

PLEASE NOTE: The views expressed in these materials are those of the authors and do notnecessarily represent the views of the Department of Veterans Affairs or the National Insti-tute for Occupational Safety and Health.


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Introduction

High-risk patient handling tasks lead to work-related musculoskeletal disorders (MSDs) forperioperative registered nurses and other

members of the perioperative team. A task forceincluding representatives from AORN, the NationalInstitute for Occupational Safety and Health

(NIOSH), the Patient Safety Center of Inquiry at theJames A. Haley Veterans Administration MedicalCenter (VMAC), and the American Nurses Associa-tion (ANA) was formed to identify high-risk tasksperformed in the perioperative area and to developevidence-based solutions to minimize MSDs. This isthe first in a series of articles to describe ergonomicsolutions for high-risk patient handling tasks in theperioperative clinical setting.

Background/Statement of Problem

Perioperative registered nurses and the perioper-ative team are routinely faced with a widearray of occupational hazards in the periopera-

tive setting that place them at risk for work-relatedMSDs.1-3 MSDs are one of the most frequently occur-ring and costly types of occupational issues affectingnurses.2,4,5 Nurses working in the private sector had11,800 MSDs reported in 2001. The majority (nearly9,000) were back injuries.5 More than a third (36%)of the injuries requiring time away from work wereback injuries.5 One recent study found that morethan half of all nurses (52%) complain of chronic

back pain. Another study revealed that 12% ofnurses planning to leave the profession indicatedback injuries were either a main or contributing fac-tor.6 A different study identified that concern for per-sonal safety in the health care environment was thereason given by 18.3% of the RNs for leaving theprofession.7 While back injuries are one of the mostcommon occupational injuries in the health careindustry, one study found that injuries of the shoul-der and neck were more likely to prevent nursesfrom doing their work than low back pain.6,8-10 Whenthe demands of the job (eg, physical demands, work

environment, workplace culture) are incompatible

with the capacity of the worker, the risk of MSDs isincreased.1,2,11 The connection between risk factorsand MSDs is stronger when exposures are intenseand prolonged and when there are several risk fac-tors present at the same time.12

The consequences of MSDs are severe. Employ-ees who experience pain and fatigue are less pro-ductive, less attentive, more prone to make consis-tent mistakes, and more susceptible to injury, andthey may be more likely to affect the health andsafety of others. Nurses suffering from disabling backinjuries and fear of being injured have contributed tothe number of nurses leaving the profession, thusincreasing the nursing shortage. Workplaces withhigh incidences of MSDs report increases inlost/modified workdays, higher staff turnover,increased costs, and adverse patient outcomes.7,13-15

The purpose of this project was to identify high-risktasks in perioperative nursing practice and to designergonomic solutions to eliminate or reduce occupa-tional risk to workers in these clinical settings.

AORN regards the well-being of the periopera-tive team members as paramount to the provisionof safe patient care. The physical demands of theperioperative environment expose perioperativehealth care providers to high-risk tasks that putthem in jeopardy of MSDs. A safe workplace isnecessary to have a positive impact on the healthand well-being of both the patient and the healthcare provider. AORN is committed to providingresources for the development of a safe periopera-tive work environment. For this reason, the Associ-ation contacted Audrey Nelson, PhD, RN, FAAN,to develop a plan to address the unique risks asso-ciated with perioperative practice.

Methods

An expert panel was convened to address riskfactors for musculoskeletal disorders forregistered nurses and other members of the

perioperative team. Due to the complexity of theissues, the interdisciplinary panel included expertsin perioperative nursing, ergonomics, biomechan-

ics, engineering, industrial hygiene, and injury

Development of theAORN Guidance Statement:Safe Patient Handling and Movement

in the Perioperative Setting

Audrey Nelson, PhD, RN, FAAN; Thomas R. Waters, PhD; Deborah G Spratt, RN, BSN,MPA, CNAA, CNOR; Carol Petersen RN, MAOM, CNOR; Nancy Hughes, MHA, RN AORN, Inc. All rights reserved.

Safe Patient Handling and Movement in the Perioperative Setting 5


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AORN Guidance Statement


prevention. The professional nurse representatives

included clinical, administrative, education andresearch perspectives. The expert panel includedpartnerships from the National Institute for Occu-pational Safety and Health, the James A. Haley Vet-erans Administration Medical Center Patient SafetyCenter of Inquiry (Tampa, Fla), the AmericanNurses Association, and AORN.

The panel met over an 18-month period in face-to-face meetings, conference calls, and electroniccommunications until panel members were able toachieve consensus. Through systematic assessmentof task demands, direct measurement of weights

and forces involved in the tasks, and direct observa-tion of work tasks and equipment, the panelapplied ergonomic principles to develop clinicaltools for utilization in the perioperative area withthe goal of reducing work-related MSDs.

The clinical tools were developed based on pro-fessional consensus and evidence from researchand were pilot-tested in several facilities. Initially,the team developed a comprehensive list of tasksperformed by OR nurses that were physicallydemanding or contained physically demandingelements. The range of tasks was evaluated and

condensed into a list of seven specific tasks ofinterest. After the seven tasks were identified, theteam developed ergonomic tools using the follow-ing process.

1. All members of the expert panel discussedeach task and provided input into how the taskwas performed.

2. The professional nurses on the team identifiedthe various physical task requirements of theselected task.

3. Based upon this initial assessment, the techni-

cal experts on the team then selected the mostimportant risk factors associated with the task(eg, pushing, pulling, lifting), selected the mostappropriate criteria for determining recom-mended exposure limits for the identified riskfactors, and developed weight and force limitsfor the specific tasks that appear in the deci-sion logic for each tool.

The process used by the ergonomists to developthe weight or force limits involved selecting the appropriate physical constraint

criteria,

evaluating the various tasks, and

calculating strength and lifting capability lim-its based on the selected constraints.For each tool, the developers provided a rationale

for the selected criteria and how weight and forcelimits were calculated. Empirical data were used toderive the recommended maximum forces andweights for manual handling for a wide range oftasks performed in the OR work environment. Theseergonomic tools were based on consensus andergonomic criteria typically used in assessing thephysical demands of manual handling activities.

Identification of High-Risk Tasks

The first step in the process was to identify high-risk tasks performed in the perioperative setting.High-risk tasks include job demands that push

the limits of human capabilitieseg, heavy loads,sustained awkward positions, bending and twisting,reaching, fatigue or stress, force, or standing for longperiods of time. It is the combination of frequency,duration, and stress of these tasks that predisposenurses to MSDs. Furthermore, the perioperative set-ting has some unique challenges due to the use of

anesthesia rendering patients unable to assist inmovement and needing further protection frominjury. Several high-risk tasks have been identified inoperating room settings, including the following.

Lateral transfer from stretcher to OR bed2,3,13

Few would argue that one of the highest risk patienthandling tasks is patient transfer. Patient transfers canstart with the patient in a sitting position (ie, verticaltransfer) or when the patient is supine (ie, lateraltransfer).16 Lifting and moving patients is a frequentoccurrence in the perioperative setting. Patients are

transferred to and from transport carts and the ORbed. Patients are repositioned once they are on theOR bed. The perioperative setting poses a uniquechallenge in that many of the patients are completelyor partially dependent due to general or regionalanesthesia or sedation. Patients who are unconsciouscannot move or feel pain and must be protected frominjury. This often requires members of the periopera-tive team to manually lift the patient or the patientsextremities several times. The position required, andthe size and weight of the patient, may increase therisk for MSDs to perioperative team members. This

problem is exacerbated with large or obese patients.


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Repositioning patients on OR beds2

To access key body parts, the patient often must berepositioned on the OR bed. Further, the periopera-tive nurse monitors patient body alignment andtissue integrity during long procedures and mayneed to reposition the patient.

Lifting and holding legs, arms, head for prepping2,13

Preparing a limb for surgery generally requires thelimb to be raised in order to complete circumferen-tial skin preparation. The limb can be suspended by aperson holding the limb or by using a holdingdevice. When the limb is held manually during theentire skin prep, it is usually done by one personwhile a second person performs the skin prep. Insome instances, if the limb is small or only the distalportion needs to be prepped, the person performingthe skin prep also may hold the limb. If a holdingdevice is used, the limb still needs to be lifted tocomplete the prep on the area resting on the holder.The person lifting the extremity needs to hold thelimb far from his or her body to maintain asepsis. Thesize of the limb, length of time held, posture neces-sary to hold the extremity, and physical ability of theperson doing the holding all contribute to the abilityof the caregiver to safely perform this task.

Prolonged standing2

Perioperative registered nurses also are prone topain and fatigue from static posture during surgicalprocedures. The sterile perioperative team mem-bers are most likely to stand in one place forextremely long periods of time. The sterile teammembers must maintain the integrity of the sterilefield, which prevents them from changing levels bysitting in a chair that is lower than the sterile fieldto rest and then standing up again. Both acute andchronic back, leg, and foot pain are frequent com-

plaints resulting from standing in one place forlong periods of time.

Holding retractors for extended periods of time2

In addition to standing for long periods of time,perioperative team members performing in the roleof first assistant may be required to hold retractorsor body parts for long periods of time. Manualretraction provides exposure of the operative siteand is accomplished by gripping and pulling on aretractor or using the hand to retract or steadyorgans. This manual retraction often results in awk-

ward posture. The height of the surgical field in

relation to the person providing retraction influ-

ences the risk for MSDs.17

Prolonged standing,trunk flexion, neck flexion, and arms held higherthan the optimal working height place periopera-tive team members at risk for MSDs.

Lifting and carrying supplies/equipment2,3,13

Perioperative personnel frequently are required tocarry unsterile and sterile supplies, instrument trays,and other equipment. The weight of an instrument setcan vary, but sets can weigh as much as 40 pounds.Sterile instrument sets are wrapped in imperviousnonwoven material or contained in closed, hard-sur-faced container systems. Both methods can presentlifting and carrying problems. Heavy wrapped instru-ment sets have no handles and are difficult to carry.Container systems have handles but may increase theweight of the tray. In an effort to keep cost down andconserve storage space, instrument trays may beloaded with too many instruments to be safely car-ried. Removing large instrument sets that have beenflash sterilized places the staff at risk for injury. Tomaintain sterility of the sterilized items, a personmust lift and hold the sterile instrument pan awayfrom his or her body. The weight of the pan and theheight of the person removing the pan contribute tothe degree of MSD risk to the individual.

Pushing, pulling, moving equipment on wheels2,3,13

Perioperative nurses and other perioperative person-nel are frequently required to move (ie, by pushingor pulling) heavy equipment (eg, OR beds, portablemicroscopes, portable C-arm imaging machines)several times during the day. These machines arevery expensive and often must be shared betweenseveral individual operating rooms. OR beds arevery heavy and difficult to move by themselves,even without a patient. When an OR bed is moved

with a patient on it, the risk of injury increases forboth the worker and the patient.

Review Process

Once the expert panel had completed itswork, an extensive peer review process wasundertaken to refine the ergonomic solu-

tions. The reviewers included nationally knownexperts in ergonomics, biomechanics, engineering,industrial hygiene, and injury prevention. The panelalso obtained administrative reviews from NIOSH,

ANA, and the Veterans Health Administration




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(VHA), as well as technical review from NIOSH. To

ensure that the document could be generalizedacross diverse clinical settings, the reviewersincluded perioperative nurses working in all phasesof the perioperative setting (ie, preoperative, intraop-erative, postoperative areas). Surgery and other inva-sive procedures are performed in multiple settingsthat require patient transfer, patient positioning, lift-ing and holding body parts, lifting and carryingequipment and supplies, pushing/pulling equip-ment, standing for long periods of time, and holdingretractors. These setting include, but are not limitedto, inpatient operating rooms, ambulatory surgery

centers, office-based surgery centers, and interven-tional procedure units.A total of 88 clinical and ergonomic experts were

sent requests for review and comment based ontheir ergonomic expertise or perioperative clinicaland/or management experience. The panel wasasked to review the document from their individualarea of expertise for clinical applicability, technicalaccuracy, relevance, and usefulness. An organizedprocess included the use of a formal comment formand a specific time frame. Comments were collatedand evaluated by the task force for acceptance, and

the document was modified as appropriate.

Overview of Solutions

The task force created solutions for each high-risk task identified in perioperative settings.Using principles of ergonomics, scientific

evidence, and clinical trials conducted at the VAPatient Safety Center of Inquiry, the following solu-tions were developed. A brief description of eachof the seven tools is included in this article.

The Algorithm for Safe Lateral Transfer from thestretcher to and from the OR bed was developed tostandardize decision making about the number ofstaff and type of technology needed to perform thistask safely.

The Algorithm for Safe Positioning/Reposition-ing the Patient on the OR bed to and from thesupine position was developed to standardize deci-sion making about the number of staff and type oftechnology needed to perform this task safely.

The Guidelines for Safe Lifting and Holding Legs,Arms, and Head for Prepping were developed toidentify safe time limits for one-handed and two-handed lifts for each body part.

The Algorithm for Prolonged Standing was

developed to standardize decision making aboutthe time limits and type of technology needed toperform the task safely.

The Algorithm for Retraction was developed tostandardize decision making about the type oftechnology and techniques needed to perform thetask safely.

The Guidelines for Lifting and Carrying Suppliesand Equipment were developed based on theNIOSH Lifting Index.18,19 This tool includes recom-mendations for 14 common types of equipmentused in the OR. These guidelines were based on

weight lifted, horizontal distance, vertical locationorigin and destination, and distance carried andindicate the level of risk (ie, minimal risk, poten-tial, or considerable) for each task.

The Guidelines for Safe Pushing, Pulling andMoving Equipment on Wheels were developed,based on Liberty Mutuals push force limits for sev-eral devices commonly used in the OR, to stan-dardize the number of staff and types of technologyneeded to perform the task safely.

Future Plans

The final document, AORN guidance state-ment: Safe patient handling and movement inthe perioperative setting, was reviewed by

NIOSH, ANA, VHA, and AORN and was subjectedto extensive peer review on a national level. It alsowill undergo pilot testing; the next step is to testthe tools and algorithms in different types of peri-operative settings. The variety of facilities that per-form surgery or other invasive procedures includemetropolitan inpatient hospitals, trauma hospitals,rural hospitals, freestanding ambulatory surgerycenters, hospital-based ambulatory surgery facili-ties, and office-based surgery centers. Organiza-tions testing the tools will be asked to evaluate theapplicability, acceptance, and availability of therecommended technology.

The wide adoption of safe ergonomic practiceswill help to promote a safe perioperative workenvironment and protect perioperative team mem-bers. To that end, AORN will seek educationalopportunities and endorsement by other periopera-tive disciplines. This article serves as the first in aplanned series to provide detailed justification foreach solution identified in the guidance statement.




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Description of the Problem

Perioperative registered nurses and the perioperativeteam are routinely faced with a wide array of occupa-tional hazards in the perioperative setting that placethem at risk for work-related musculoskeletal disor-ders.1-3 Musculoskeletal disorders are injuries or disor-ders of the muscles, nerves, tendons, joints, cartilage,

or spinal discs associated with actions such as overex-ertion, repetitive motion, and bodily reaction.4,5 The USDepartment of Labor does not include injuries causedby slips, trips, falls, motor vehicle accidents, or similaraccidents in their definition of musculoskeletal disor-ders.4 Musculoskeletal disorders are one of the mostfrequently occurring and costly types of occupationalissues affecting nurses.2,6,7 More than a third (ie, 36%)of the musculoskeletal injuries that nurses reportedrequiring time away from work were back injuries.8

Among the nurses working in the private sector, nearly9,000 had back injuries.8,9 One study revealed that

12% of nurses planning to leave the profession indi-cated that back injuries were either a primary or con-tributing factor to their decision.10 While back injuriesare one of the most common occupational injuries inthe health care industry, injuries of the shoulder andneck were more likely to prevent nurses from perform-ing their work than low back pain.10-13 The US Depart-ment of Health and Human Services report on nursingidentified concern for personal safety in the healthcare environment as the reason given by 18.3% ofnurses for leaving the profession.14

When the workers physical ability, task, work-

place environment, and workplace culture are notcompatible, there is an increased risk of a muscu-loskeletal disorder.1,2,15 The connection betweenphysical risk factors and musculoskeletal disorders isgreater when exposures are intense and prolongedand when several occupational risk factors are pres-ent at the same time.16 Examples of physical stressorsencountered in health care include forceful tasks, repetitive motion, awkward posture, static posture,

moving or lifting patients and equipment,

carrying heavy instruments and equipment, and overexertion.1-3,11,12,14,17-26

The perioperative setting poses unique challengesrelated to the provision of patient care and completionof procedure-related tasks. This highly technical envi-ronment is equipment intensive and necessitates thelifting and moving of heavy supplies and equipmentduring the perioperative team members work period.

Many of the patients having surgical or other invasiveprocedures are completely or partially dependent onthe caregivers due to the effects of general or regionalanesthesia or sedation. Patients who are unconsciouscannot move, sense discomfort, or feel pain, and theymust be protected from injury. This may require theperioperative team to manually lift the patient or thepatients extremities several times during a procedure.The following are among the high-risk tasks specific toperioperative nurses identified that will be addressedin the following discussion of ergonomic tools: transferring patients on and off OR beds,2

repositioning patients in the OR bed,2

lifting and holding the patients extremities,2

standing for long periods of time,2

holding retractors for long periods of time,2

lifting and moving equipment,2 and sustaining awkward positions.Transferring, lifting, and handling patients has

been identified as the most frequent precipitatingtrigger of back and shoulder problems in nurses.2,27

Certain patient handling tasks (eg, patient transfers)have been identified as high risk for musculoskeletalinjuries to health care workers.27 Lifting and moving

patients is a frequent activity in the perioperative set-ting; for example, caregivers transfer patients to andfrom transport carts (eg, stretchers) and the OR bedmany times during a typical work shift.

Health care providers often reposition patientsonce they are on the OR bed to provide appropriateexposure of the surgical site. This high-risk activityrequires team members to physically lift and maneu-ver the patient or a patients extremity while simulta-neously placing a positioning device. The patientsweight may not be evenly distributed; the extremitysmass may be bulky and asymmetric, and it may be

difficult to hold the extremity close to the health care

AORN Guidance Statement: Safe Patient Handlingand Movement in the Perioperative Setting


AORN, Inc. All rights reserved.


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providers body during positioning maneuvers.28 Addi-tionally, concern for the patients airway, maintaining

his or her body alignment, and supporting the extrem-ities may make it difficult for team members to posi-tion themselves in an ergonomically safe position,thus exacerbating physical demands.

Several unique aspects of high-risk patient handlingtasks associated with prepping a patients limb havebeen identified.29 Preparing an extremity for surgerygenerally requires it to be elevated to allow completecircumferential skin preparation. The limb can be sus-pended by a person holding the limb or by placing thelimb in a holding device. In some instances, the limbmay be held manually during the entire skin prep

while a second person performs the skin prep. Theperson performing the skin prep may also hold thelimb if the limb is small or if only the distal portionneeds to be prepped. To maintain asepsis, the personlifting the extremity is forced to hold the limbextended away from his or her body. The size of thelimb, length of prep time, posture necessary to holdthe extremity, and the physical capability of the personholding the limb all contribute to the ability of thecaregiver to safely suspend the limb for the requiredprep. The following questions should be consideredwhen determining how to safely raise and hold a limb.

Does the limb need to be raised for the entiresurgical skin prep?

Does the limb need to be lifted by scrubbed orunscrubbed personnel?

Is the person holding the limb strong enoughto perform the task?

Is there an alternative practice that can beadopted?

Is there equipment that could be used to sup-port the task?

Is it possible to hold a heavy limb safely with-out risk of injury to the nurse or the patient?29

Perioperative registered nurses are prone to painand fatigue from static posture during surgical pro-cedures. The entire perioperative team spends a sig-nificant amount of time on their feet during thecourse of a shift; however, sterile perioperative teammembers may be required to stand for much longerperiods of time. The sterile team members mustmaintain the integrity of the sterile field, which pre-cludes them from changing levels. They should notalternate between sitting in a chair that is lower thanthe sterile field and a standing position. Acute andchronic back, leg, and foot pain are frequent com-

plaints resulting from standing in one place for long

periods of time. The following factors should be con-sidered during surgical or other invasive procedures.

Are the sterile members of the team at the appropriate height for the level of the

OR bed? adopting awkward positions to work effectively? positioned in close proximity to the patient to

perform required tasks? stretching and relaxing muscles regularly?29

Perioperative nurses and other perioperative per-sonnel are frequently required to push or pull heavyequipment (eg, OR beds, portable microscopes,video carts). This equipment is very expensive andoften must be shared between several individual

operating rooms. Unoccupied OR beds are veryheavy and difficult to move. Moving an occupiedOR bed is not recommended because the risk ofinjury increases for both the worker and the patient.

Perioperative personnel and central processingpersonnel are frequently required to carry sets of sur-gical instruments. Instrument set weights vary andmay weigh as much as 40 pounds. Instrument traysare wrapped with impervious nonwoven material orcontained in a ridged container system. Both packag-ing methods can present lifting and carrying prob-lems. Wrapped instrument sets that are too heavy

may pose an additional problem because they haveno handles and are awkward to carry. Rigid con-tainer systems often have handles that make carryingeasier, but the weight of the container itself adds tothe total weight of a full tray. In an effort to keep costsdown and conserve storage, space instrument traysmay be inappropriately prepared and too heavy to liftor carry safely. Instrument sets that are flash sterilizedrequire staff members to aseptically remove the hottrays from the sterilizer. The weight of these trays andthe height of the person removing them from the ster-ilizer in relation to the height of the sterilizer cham-

ber contribute to the degree of risk to that individual.The consequences of musculoskeletal disorders are

severe. Employees who experience pain and fatigueare less productive and attentive, more prone to makemistakes, more susceptible to further injury, and maybe more likely to affect the health and safety of others.Nurses suffering from disabling back injuries or thefear of getting injured have contributed to the numberof nurses leaving the profession, thus increasing thenursing shortage. Workplaces with high incidences ofmusculoskeletal disorders report increases in lost ormodified workdays, higher staff member turnover,

increased costs, and adverse patient outcomes.14,29,30


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Description of the Process

The 20052006 Workplace Safety Task Force wascharged by AORN President Sharon McNamara, RN,MS, CNOR, to prepare a guidance document forergonomically healthy workplaces. In addition, thetask force was charged with forming a collaborativearrangement with the National Institute for Occupa-tional Safety and Health (NIOSH) and the AmericanNurses Association (ANA) to work together to discuss,design, and advance the agenda of healthy work sitesfor perioperative professionals, to include ergonomicsafety. This document was developed by AORN withthe assistance of a panel of experts from the Patient

Safety Center of Inquiry, Tampa, Fla; the James A.Haley Veterans Administration Medical Center(VMAC); the NIOSH Division of Applied Researchand Technology Human Factors and ErgonomicsResearch Team; and ANA.

Members of the task force examined currentresearch, literature, and patient care practices to eval-uate and make recommendations to promote patientand caregiver safety when performing activities in aperioperative setting. While there are several high-

risk tasks specific to perioperative nurses, the taskforce identified seven key activities as the starting

point for developing recommendations. Some ofthese recommendations are based upon current tech-nology that can be immediately implemented. Oth-ers, such as use of ceiling lifts in operating rooms, arein development or are projected patient handlinginnovations. This group will continue to examinewhat is available and encourage manufacturers todevelop new and innovative technologies to achievethe optimal safety of the patient and the caregiver.Development of this equipment is critical for suc-cessful implementation of these ergonomic tools.

The ergonomic tools developed for this guidance

document are based on previous work by AudreyNelson, PhD, RN, FAAN; experts within the VeteransAdministration (VA); and nationally recognizedresearchers.28 The ergonomic tools for safe patienthandling and movement have been designed withthe goal of eradicating job-related musculoskeletaldisorders in perioperative nurses. The ergonomictools and algorithms were developed based on pro-fessional consensus and evidence from research.Plans are under way for pilot tests in several facilities.

Andrea Baptiste, MA (OT), CIEErgonomist/BiomechanistPatient Safety Center of Inquiry

James A. Haley Veterans HospitalTampa, Fla

Edward Hernandez, RN, BSNOR Nurse Manager


Nancy Hughes, RN, MHADirector, Center for Occupational and

Environmental HealthAmerican Nurses AssociationSilver Spring, Md

Valerie KelleherInformation SpecialistPatient Safety Center of Inquiry


John D. Lloyd, PhD, MErgS, CPEDirector, Research LaboratoriesPatient Safety Center of Inquiry

James A. Haley Veterans Hospital

Tampa, Fla

Mary W. Matz, MSPHVHA Patient Care Ergonomics Consul-tant and Industrial HygienistPatient Safety Center of Inquiry


Karen Moser, RN, BSN, CNOREducatorWilliam S. Middleton VA HospitalMadison, Wis

Audrey Nelson, PhD, RN, FAAN

Director, Patient Safety Center of InquiryJames A. Haley Veterans HospitalTampa, Fla

Carol Petersen, RN, BSN, MAOM, CNORPerioperative Nursing SpecialistAORN, IncDenver, Colo

Lori Plante-Mallon, RN, CNORPerioperative RNStrong Memorial HospitalUniversity of Rochester Medical CenterRochester, NY

Kristy Robinson, RN, BSN, CNORPerioperative RNTampa General HospitalTampa, Fla

Manon Short, RPT, CEASInjury Prevention CoordinatorTampa General HospitalTampa, Fla

Patrice Spera, RN, MS, CNOR, CRNFADirector of Clinical ServicesTampa Bay Specialty Surgical Center

Pinellas Park, Fla

Deborah G. Spratt, RN, MPA, CNAA,CNORClinical SpecialistUniversity of Rochester Medical CenterRochester, NY

Thomas R. Waters, PhD, CPELeader of the Human Factors ErgonomicsResearch TeamNational Institute for OccupationalSafety and HealthCincinnati, Ohio

Task Force Members


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Ergonomic Tool #1

LATERAL TRANSFER FROM STRETCHER TO AND FROM THE OR BED

Canpatient transfer

withoutassistance?

StartCaregiver assistance not

required. Stand by for safetyas needed.

Is weight> 73 lbs?

Is weight> 157 lbs?

Use lateral transferdevice (min. 4caregivers).*

Use one of the follow-ing: mechanical lift withsupine sling, mechani-

cal lateral transferdevice, or air-assistedlateral transfer device(min. 3-4 caregivers).*

Use 23caregivers.*

Use assistive technology(min. 34 caregivers)*

A mechanical device is preferable forthis task. Additional technologies are

needed for turning a patient from supineto prone and from prone to supine.

Yes

No

What is thestarting

position?SupineProne

Will patientstay supine?

No

Yes

No

No

Yes

Yes

Note: < means less than

> means greater than

The number of personnel to safely transfer the patient should be adequate to maintain the

patients body alignment, support extremities, and maintain patients airway. For lateral transfers, it is important to use a lateral transfer device that extends the length ofthe patient.

Current technologies for supine-to-prone include the Jackson frame and the spine table. Destination surface should be slightly lower for all lateral patient moves. A separate algorithm for prone-to-jackknife is not included because this is assumed to be a

function of the table. If the patients condition will not tolerate a lateral transfer, consider the use of a mechani-

cal lift with a supine sling. During any patient transfer task, if any caregiver is required to lift more than 35 lbs of a

patients weight, assistive devices should be used for the transfer. While some facilities may attempt to perform a lateral transfer simultaneously with posi-

tioning the patient in a lateral position (ie, side-lying), this is not recommended until newtechnology is available.

The assumption is that the patient will leave the operating room in the supine position.* One of the caregivers may

be the anesthesia provider.


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Ergonomic Tool #1:

Lateral Transfer From StretcherTo and From the OR Bed

Transferring a patient to and from the OR bed isone of the first actions of the perioperative team.The AORN Recommended practices for position-ing the patient in the perioperative practice settingrecommends that the perioperative registered nurseperform a preoperative assessment for patient-spe-cific positioning needs.31 Based on that assessmentand using Ergonomic Tool #1, the patient will be

transferred to and from the OR bed in an ergonom-ically safe manner.

Supine to Prone TransferAssuming that one caregiver or anesthesia careprovider supports the patients head and neck duringsupine to prone transfers, the patients remainingbody mass equals 91.6% of his or her total bodymass.32 Using the approach for lifting and holding, amaximum two-handed load to achieve 75% USadult female design goal equals 22.2 lbs (10.1 kg).*Typically one of the four caregivers moving a patient

is the anesthesia care provider who maintains theairway and supports the patients head. Two care-givers plus the anesthesia care provider can safelytransfer a patient weighing up to 48.5 lbs (22.0 kg)from supine to prone position. Three caregivers, plusan anesthesia care provider, can safely transfer apatient weighing up to 72.7 lbs (33.0 kg). If thepatients weight is greater than 73 lbs, it is necessaryto use assistive technology and a minimum of threeto four caregivers. Although this has been identifiedas a gap in technology, a mechanical device ispreferable for this task and should be developed.

Supine to Supine TransferThe desirable approach for lateral transfer of a patientinvolves use of a lateral transfer device (eg, friction-reducing sheets, slider board, and air-assisted transferdevice). If only a draw sheet is used without a lateraltransfer device, the care provider exerts a pull forceup to 72.6% of the patients weight.33 Assuming thatone caregiver or anesthesia care provider supportsthe patients head and neck to maintain the airwayduring lateral transfers, the remaining mass of thepatients body equals 91.6% of his or her total body

mass.32

Research indicates that for a pulling distance

of 6.9 ft (2.1 m) or less, where the pull point (ie, start-

ing point for the hands) is between the caregiverswaist and nipple line, and the task is performed nomore frequently than once every 30 minutes, themaximum initial force required equals 57 lbs (26 kg)and the maximum sustained force needed equals 35lbs (16 kg).34 Therefore, each caregiver can safelycontribute a pull force required to transfer up to 48lbs (35 lbs/0.726 as referenced above). For one care-giver, plus the anesthesia care provider, maximumpatient weight equals 52.6 lbs (48lbs/0.916 as refer-enced above). Two caregivers plus the anesthesiacare provider can safely transfer a patient up to 104.8

lbs (48 x 2)/0.916 as referenced above). Three care-givers plus the anesthesia care provider can safelytransfer a patient up to 157.2 lbs (48 x 3)/0.916 asreferenced above). If the patient is > 157 lbs, use anappropriate mechanical lifting deviceie, mechani-cal lift with supine sling, mechanical lateral transferdevice, or air-assisted lateral transfer deviceand aminimum of three to four caregivers.

*Calculation of Design Goal

To accommodate the design goal of 75% of the US

adult female working population, maximum load for aone-handed lift is calculated to be 11.1 lbs (5.0 kg),assuming a worst-case scenario where the patient loadmay be handled at full arms length. This is determinedby calculating the strength capabilities for the 25th per-centile US adult female maximum shoulder flexionmoment (25th percentile strength = 31.2 Nm, based onmean of 40 Nm and standard deviation of 13 Nm,therefore 25th percentile = 31.2 Nm)35 and the 75thpercentile US adult female shoulder to grip length(75th percentile length = 630 mm, based on mean of610 mm and standard deviation of 30 mm).36 Therefore,

maximum one-handed lift is calculated as 31.2 Nmdivided by 0.63 m, which equals 49.5 N, or 11.1 lbs.Maximum load (for one person) for a two-handed

lift (22.2 lb/10.1 kg) is calculated as twice that of aone-handed lift. According to Rohmert, musclestrength capabilities diminish as a function of time.37

Therefore, maximum loads for two-handed holding ofbody parts are presented for one-, two-, and three-minute durations. After one minute, muscle endurancehas decreased by 48%; by 65% after two minutes; andafter three minutes of continuous holding, strengthcapability is only 29% of initial lifting strength.


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Is the patient< 68 lbs?

Ergonomic Tool #2

POSITIONING/REPOSITIONING THE PATIENT ON THE OR BED INTO AND FROM THE SUPINE POSITION

What is thesurgical position? Start

Yes

No

Manual lifting orlowering of torso

(min. 3 caregivers)See (3) below

No

Yes

Yes

Note: < means less than> means greater than

(1) Mechanical devices are preferable for this task, buttheir practicality has not yet been tested. There arespecial slings and straps that can be used withmechanical devices. For example, turning straps canbe used to turn a patient to and from lateral or supine,or limb support slings can be used to lift the legs toand from lithotomy. More research is needed.

(2) Use the automatic semi-Fowler positioning feature ofan electric table if available.

(3) One of these caregivers could be the anesthesia

provider to hold the head and maintain the airway.



Use assistive technology (min. 3 caregivers)See (1 and 2) below

Proceed withprocedure

Manual positioning approved(min. 4 caregivers)

See (3) below

To/from semi-Fowlerusing beach chair device

See (1) below

To/fromlateral

Use assistive technology(min. 3 caregivers)

See (1) below


Manual 2-handed lift oflegs (min. 2 caregivers

[1 each leg]) or useassistive technology

See (1) belowNo

Use assistivetechnology

(min. 4 caregivers)See (1) below


During any patient handling task, if any caregiver isrequired to lift more than 35 lbs of a patients weight, anassistive device should be used.

The number of personnel to safely position the patientshould always be adequate to maintain the patients bodyalignment.

A separate algorithm for prone-to-jackknife is not included

because this is assumed to be a function of the table.

To/fromlithotomy


17/36



Ergonomic Tool #2: Positioning andRepositioning the Patient on the OR

Bed Into and From the Supine Position

The AORN Recommended practices for position-ing the patient in the perioperative practice settingrequire that the perioperative nurse shouldactively participate in monitoring patient bodyalignment and tissue integrity based on soundphysiologic principles. It further states, an inade-quate number of personnel and equipment canresult in patient injury.31 Ergonomics Tool #2 pro-vides evidence-based guidelines to assist the peri-operative registered nurse and other team members

to position and reposition the patient on the ORbed in a safe manner for the patient and the team.

Moving the Patient Into andOut of a Semi-Fowler Position

The mass of a patients body from the waist up,including the head, neck, and upper extremities,equals 68.6% of the patients total body weight.32

Added to this is the estimated weight of the equip-ment (20 lbs/9.1 kg). To accommodate at least 75%of the US adult female working population, the

maximum load for a two-handed lift is 22.2 lbs(10.1 kg). This is determined based on 25th per-centile US adult female shoulder strength capabili-ties35 and 75th percentile US adult female armlength.36 Therefore, three caregivers together couldlift up to 66.6 lbs (10.3 kg), which equates to a 68-lb (30.1 kg) patient.* Mechanical devices and aminimum of three caregivers are preferable if thepatient weighs more than 68 lbs. An example of anappropriate mechanical device is the automaticsemi-Fowler positioning feature of an electric ORbed. Further research to address gaps in technology

is recommended.

Positioning the Patient Into andFrom the Lateral Position

Positioning or repositioning a patient into or out of alateral position involves push/pull forces rather thanlifting forces. Assuming that one caregiver or anesthe-sia care provider supports the patients head and neckduring lateral positioning, the patients remainingbody mass equals 91.6% of total body mass.32 Basedon the Liberty Mutual tables (see Table 3 underErgonomic Tool #7) for a pulling distance of 6.9 ft(2.1 m) or less, with a pull point (ie, starting positionof the hands) between the caregivers waist heightand nipple line, performed no more frequently thanonce every 30 minutes, maximum initial force equals

57 lbs (26 kg), and maximum sustained force equals35 lbs (16 kg).34 Therefore, two caregivers, plus ananesthesia care provider maintaining the patientsairway, can safely position a patient weighing up to76 lbs (34.5 kg) (35 lbs x 2 care providers/0.916as referenced above). Three caregivers plus an anes-thesia care provider can safely position a patientweighing up to 115 lbs (52.2 kg) (35 lbs x 3 careproviders/0.916 as referenced above). If the patientsweight exceeds 115 lbs, lateral positioning devicesare needed. Further research is needed to enhancetechnology to address this task.

Positioning the Patient Into andFrom the Lithotomy Position

When lifting and holding body parts, the maximumload for a two-handed lift is 22.2 lbs (10.1 kg).Each complete lower patient extremity, includingthigh, calf, and foot, weighs 15.7 % of the patientstotal body mass. Therefore, one caregiver cansafely perform this task if the patient weighs 141lbs (64.1 kg) or less because each leg is estimatedto be less than 22.2 lbs.33

Caregivers attempting to lift the patients legs using

two hands can each safely lift one leg for patientsweighing less than 141 lbs. Patients weighing morethan 141 lbs require assistive technology or fourcaregivers (ie, two to lift each leg). A mechanicaldevice such as support slings can be used to lift thelegs to and from the lithotomy position. Furtherresearch is needed to enhance availability of technol-ogy to address this task.

*Maximum patient weight = (Maximum 2-handed lift (22 lbs) x 3 caregivers) equipment weight (20 lbs) = 68 lbs

(68 lbs) Percentage of patient weight above the waist (0.686)


18/36



PatientWeight lbs

(kg)

BodyPart

Body PartWeightlbs (kg)

Lift1-hand

Lift2-hand

Hold2-hand163 kg)

Leg > 57 lbs (26 kg)

Arm > 18 lbs (8 kg)

Head > 30 lbs (14 kg)

Ergonomic Tool #3: Lifting and

Holding Legs, Arms, and Head forPrepping in a Perioperative Setting

IntroductionAORNs Recommended practices for skin preparationof patients states that when indicated, the surgicalsite and surrounding area should be prepared with anantiseptic agent. The prepared area of skin and thedrape fenestration should be large enough to accom-modate extension of the incision, the need for addi-tional incisions, and all potential drain sites.38 To

accomplish this task, a member of the perioperativeteam may need to hold the extremity so that the appro-priate body part is prepared in the required manner.

Ergonomic Tool #3 shows the calculations foraverage weight for an adult patients leg, arm, andhead as a function of whole body mass, rangingfrom slim to morbidly obese body type. Weights arepresented both in US (lbs) and metric (kg) units.Maximum lift and hold loads were calculated basedon 75th percentile shoulder flexion strength andendurance capabilities for US adult females, wherethe maximum weight for a one-handed lift is 11.1lbs and a two-handed lift, 22.2 lbs.

No shading: OK to lift and hold; use clinical judgment and do not hold longer than noted.

Heavy shading: Do not lift alone; use assistive device or more than one caregiver.

LIFTING AND HOLDING LEGS, ARMS, AND HEAD FOR PREPPING

Ergonomic Tool #3


19/36



The shaded areas of the table indicate whether it

would be acceptable for one caregiver to lift the listedbody parts or hold the respective body parts for 0, 1,2, or 3 minutes with one or two hands. Respectingthese limits will minimize risk of muscle fatigue andthe potential for musculoskeletal disorders. Periopera-tive registered nurses must use clinical judgment toassess the need for additional staff member assistanceor assistive devices to lift and/or hold one of thesebody parts for a particular period of time.

Rationale and Calculations forErgonomic Tool #3

NOTE: These are guidelines for the average weightof the leg, arm, and head based upon the patientsweight. Nurses should use their clinical judgmentto assess the need for additional staff memberassistance or assistive devices to lift and/or holdone of these body parts for a particular period oftime. The maximum weight for a one-handed lift is11.1 lbs and for a two-handed lift, 22.2 lbs.

Patient weight is divided into seven categories(see Ergonomic Tool #3), ranging from very light tomorbidly obese. Normalized weight for each leg,each arm, and head is calculated as a percentage

of body weight where each complete lowerextremity (ie, upper arm, forearm, hand) weighs5.1% of total body mass and the head plus neckcombined weighs 8.4% of total body mass.32 Allweights are presented in both pounds and kilo-grams, rounded to the nearest whole unit.

To accommodate 75% of the US adult femaleworking population, maximum load for a one-

handed lift is calculated to be 11.1 lbs (5.0 kg). This

is determined by calculating the strength capabilitiesfor 25th percentile US adult female maximumshoulder flexion moment (the mean equals 40 New-ton meters; standard deviation equals 13 Nm)35 and75th percentile US adult female shoulder to griplength (the mean equals 610 mm, the standard devi-ation equals 30 mm).36 Maximum loads for one per-son for a two-handed lift (ie, 22.2 lbs/10.1 kg) arecalculated as twice that of a one-handed lift. Musclestrength capabilities diminish as a function of time;therefore, maximum loads for two-handed holdingof body parts are presented for 1, 2, and 3 minute

durations.37

After 1 minute, muscle endurance hasdecreased by 48%, decreasing by 65% after 2 min-utes, and after 3 minutes of continuous holding,strength capability is only 29% of initial liftingstrength. If the limits in Ergonomic Tool #3 areexceeded, additional staff members or assistive limbholders should be used.

Ergonomic Tool #4:Prolonged Standing

Perioperative team members who are scrubbed or

first assisting for long periods of time may be sus-ceptible to injuries caused by static load.39-44 Pro-longed standing, trunk flexion, and neck flexionare all components of static load.45,46 ErgonomicTool #4, which appears on the following page,assists perioperative team members to take protec-tive action to decrease the stress caused by pro-longed standing.


20/36



Ergonomic Tool #4PROLONGED STANDING

Start

Use fatigue-reducing techniques(eg, alternate propping one foot on

footstool, anti-fatigue mats, sit-standstool, supportive footwear).

Limit to one hour; use aportable sit-stand stool or

a portable lead shield.

No interventionrequired

Yes

No

Doesprocedure require

the use of leadaprons?

Yes

No

General recommendations Caregiver should wear supportive footwear that has the following properties:

does not change the shape of the foot; has enough space to move toes; shock-absorbing, cushioned insoles; closed toe; and height of heel in proportion to the shoe.

Caregivers may benefit from wearing support stockings/socks. Anti-fatigue mats should be on the floors. Anti-fatigue mats should be placed on standing stools. The sit-stand chair should be set to the correct height before setting the sterile field so caregivers will not be

changing levels during the procedure.* Be aware of infection control issues for nondisposable and anti-fatigue matting. Accommodations for pregnancy were considered, but the two-hour limit on prolonged standing covers this condition. Scrubbed staff should not work with the neck flexed more than 30 degrees or rotated for more than one minute

uninterrupted. Two-piece, lightweight lead aprons are recommended. During the sit-to-stand break, staff should look straight ahead for a short while.

* Recommended practices for maintaining a sterile field, in Standards, Recommended Practices, and Guidelines(Denver, Colo: AORN, Inc, 2007) 665-672.

Doescaregiver stand in

the same position morethan two hours continuously

or more than 30% ofthe work day?


21/36



Ergonomic Tool #5: Retraction

Sterile perioperative team members or those per-forming in the role of first assistant may be requiredto hold retractors or body parts for long periods oftime, in addition to standing for long periods oftime. Manual retraction used to provide exposure ofthe operative site for the surgeon often requires firstassistants to stand in an awkward posture for longperiods of time to grip and pull a retractor or to usetheir hands to retract or steady organs (eg, heart).The height of the surgical field in relation to the per-son providing retraction influences the risk for mus-culoskeletal injury.47 Prolonged standing, trunk flex-

ion, neck flexion, and arms held higher than theoptimal working height place perioperative teammembers at risk for a musculoskeletal injury.

Ergonomic Tool #6: Lifting andCarrying Supplies and Equipment

Members of the perioperative team may need to liftand carry many different types of unsterile and ster-ile supplies, instrument trays, and equipment. Thistool is intended to assist caregivers in evaluatingthese tasks and taking measures to protect them-selves. Information from Association for theAdvancement of Medical Instrumentation, theorganization that sets standards for safety and effi-cacy of medical instrumentation, recommends thatinstrument trays weigh a maximum of 25 lbs.48

Manual lifting and carrying of objects is physically

demanding and may place the worker at substantialrisk of low back pain. The NIOSH has developed anequation for calculating the recommended weight

Ergonomic Tool #5RETRACTION

Start

Assistant should be at an optimalworking height/posture for manual

retraction.* Hold retractor as close to body as

possible and maintain good posture.

Yes

No

Yes

Arm rests should be utilized as possible and be large enough to allow repositioning of the arms. Under optimal working height and posture, an assistive device should be used to lift or hold more than 35 lbs. Further research is needed to determine time limits for exposure. Since this is a high-risk task, caregivers should take

rest breaks or reposition when possible. Avoid using the hands as an approach to retraction; it is very high-risk for musculoskeletal or sharps injuries.

* Optimal working height is defined as area between the chest and the waist height to operative field. Optimalposture is defined as perpendicular/straight-on to the operative field; asymmetrical posture may be acceptable,depending on load and duration; torso twisting should be avoided at all times.

Can a self-retainingretractor be safely used

for the task?

Is manual

retraction alsonecessary?

Utilize self-retaining retractor


22/36



limit and lifting index for assessing the physical

demands of manual lifting tasks.49,50

A description ofthe NIOSH lifting equation is presented in the sec-tion entitled Other background materials.

Typical lifting tasks performed by perioperativenurses were identified and evaluated for potentialrisk of low back pain due to manual lifting using theRevised NIOSH Lifting Equation (RNLE). ErgonomicTool #6 lists the lifting index values for these tasks.According to NIOSH, tasks with a lifting index valuegreater than 1.0 place some workers at risk of lowback pain and a lifting index value greater than 3.0places many workers at risk of low back pain. In a

subsequent study that examined the effects of theNIOSH lifting index as a predictor, the risk of backpain increases when the lifting index exceeds 2.0.51

As can be seen in the table, tasks with a lifting indexvalue less than 1.0 can easily be performed manu-ally. For those tasks with a lifting index value greaterthan 1.0, however, caution should be used. Alternatehandling procedures may help reduce risk of low

back pain due to lifting these objects. The list is not

all inclusive; the NIOSH equation can be used tocalculate a lifting index value for other two-handedmanual lifting tasks not on the list.50

NOTE: Assistive devices include adjustable-height lift tables, rolling carts, two-wheeled carts,dollies, or mechanical transport devices.

Rationale and Calculations forErgonomics Tool #6

A series of typical operating room lifting tasks wereidentified and evaluated with the NIOSH Lifting Equa-tion (NLE) for potential risk of low back pain due to

manual lifting of objects in support of patient care (seeTable 1). The NLE is a tool for assessing manual liftingof objects that allows the user to calculate the recom-mended weight limit for a specified two-handed man-ual lifting task. In addition, the lifting index for the taskcan be calculated by dividing the actual weight of theload lifted by the recommended weight limit (fordetails, see Other background material).

Lifting Task Lifting Index Level of Risk

3,000 mL irrigation fluid < 0.2

Sand bags 0.3

Linen bags 0.4

Lead aprons 0.4

Custom sterile packs (eg, heart or spine) 0.5

Garbage bags (full) 0.7

Positioning devices off shelf or rack (eg, stirrups) 0.7

Positioning devices off shelf or rack (eg, gel pads) 0.9

Hand table (49 x 28); largest hand table, used infrequently 1.2

Fluoroscopy board (49 x 21) 1.2

Stirrups (twoone in each hand) 1.4

Wilson frame 1.4

Irrigation containers for lithotripsy (12,000 mL) 1.5

Instrument pans 2.0

No shading Minimal riskSafe to liftLight shading Potential riskUse assistive technology, as available

Heavy shading Considerable riskOne person should not perform alone or weight should be reduced.

NIOSH LIFTING INDEX VALUE FOR TYPICAL MANUAL LIFTING OF OBJECTS

Ergonomic Tool #6


23/36



Lifting Task Weight (lbs.) HorizontalDistance(inches)

Vertical Loca-tion-Origin

(inches)

Vertical Loca-tion-Destina-tion (inches)

DistanceCarried (feet)

Lifting Index

3000 cc IV bags

irrigation fluids

2.5 lbs 6 in 42 in 30 in 49118 ft < 0.2

Sand bags 10.5 lbs 12 in 30 in 32 in 20 ft 0.3

Linen bags 15 lbs 6 in

Set = 10 in

Floor

Set = 0 in

42 in 140251 ft 0.4

Lead aprons 16 lbs 13 in 36 in 36 in N/A

on cart

0.4

Custom sterile

packs (heart or

spine)

12.4 lbs 18 in 23 in 32 in 0.5

Garbage bags

(full)

23.6 lbs 6 in

Set = 10 in

Floor

Set = 0 in

42 in 140251 ft 0.7

Positioning

devices off shelf

or rack (stirrups)

17 lbs each (2

stirrups would

be 34 lbs)

18 in 36 in 36 in 0.7

Positioning

devices off shelf

or rack (gel pads)

825

Set to 25 lbs

18 in 36 in 36 in 510 ft 0.9

Hand table (49

x 28); largest

hand table, used

infrequently

1527 lbs

Set to 27 lbs

20 in 43 in 32 in 49118 ft 1.2

Fluoroscopy

board (49 x 21)

26 lbs 20 in 43 in 32 in 49118 ft 1.2

Stirrups (2, one

in each hand)

34 lbs 18 in 36 in 36 in 1.4

Wilson frame 27 lbs 32 in 31.5 in 32 in 49118 ft 1.4

Irrigationcontainers for

lithotripsy

(12,000 mL)

050 lbsSet to 50 lbs

6 inSet = 10

63 in(top shelf)

N/AHousekeeping

places in bags

Set to 33 in

49118 ft 1.5

Instrument pans 338 lbs

Set to 38 lbs

19 in 650 in

Set to 6 in

Varies

Set to 34 in

510 ft 2.0

DATA USED TO CALCULATE THE NIOSH LIFTING INDEX VALUES FOR TYPICAL ITEMS LIFTED IN THE OR

Table 1


24/36



Ergonomic Tool #7: Pushing, Pulling,

and Moving Equipment on WheelsIntroduction

Case preparation is a combination of many activities.The movement of patients, supplies, and equipmentin and out of the OR contributes to physical stressand should be performed based on scientific evi-dence. The recommendations in Ergonomic Tool #7are a result of research done by task force membersand include some, but not all, of the necessary activi-ties undertaken to prepare for a case.

Pushing forces were measured for equipment

listed in the following table. Maximum pushingdistances were determined based on LibertyMutuals psychophysical limits. All results are pre-sented in both US and metric units.

Based on these results, it is clear that pushing anoccupied standard hospital bed or standard or spe-

cialty OR beds, whether occupied or not, presentsa moderate to high risk of injury to the caregiver.For these situations it is strongly recommended thata minimum of two caregivers participate in thetransport task, or ideally, that a powered transportdevice is used.

RecommendationsThe recommendations in Ergonomic Tool #7 arebased on Liberty Mutuals psychophysical limits forpush forces, where hands are positioned at a mid-dle push point of 3 ft (0.92 m) from the floor orabove and task is performed no more frequently

than once every 30 minutes.34

Pushing tasks are ergonomically preferredover pulling tasks.34

Ensure that handles are at a correct pushheight of approximately 3 ft (0.92 m) from thefloor.34

OR Equipment Pushing ForceErgonomic

Recommendation

Electrosurgery unit 8.4 lbF (3.8 kgF) >200 ft (60 m)

Task is accept-able for one

caregiver

Ultrasound 12.4 lbF (5.6 kgF) >200 ft (60 m)

X-ray equipment portable 12.9 lbF (5.9 kgF) >200 ft (60 m)

Video towers 14.1 lbF (6.4 kgF) >200 ft (60 m)

Linen cart 16.3 lbF (7.4 kgF) >200 ft (60 m)

X-ray equipment, C-arm 19.6 lbF (8.9 kgF) >200 ft (60 m)

Case carts, empty 24.2 lbF (11.0 kgF) >200 ft (60 m)

OR stretcher, unoccupied 25.1 lbF (11.4 kgF) >200 ft (60 m)

Case carts, full 26.6 lbF (12.1 kgF) >200 ft (60 m)

Microscopes 27.5 lbF (12.5 kgF) >200 ft (60 m)

Hospital bed, unoccupied 29.8 lbF (13.5 kgF) >200 ft (60 m)Specialty equipment carts 39.3 lbF (17.9 kgF) >200 ft (60 m)

OR stretcher, occupied, 300 lbs 43.8 lbF (19.9 kgF) >200 ft (60 m)

Bed, occupied, 300 lbs 50.0 lbF (22.7 kgF)


25/36



For tasks where the push point is lower than

3 ft (0.92 m), maximum and sustained pushforces will be decreased by approximately15%.34

For tasks performed more frequently thanonce every 30 minutes, maximum and sus-tained push forces will be decreased byapproximately 6%.34

If push force limits are exceeded it will be nec-essary to reduce the weight of the load, usetwo or more caregivers to complete the tasktogether, or use a powered transport device.

Equipment casters need to be properly main-

tained to assist in moving equipment moreeasily.

For OR equipment not listed above, compare

physical effort to that required to push an unoc-cupied standard hospital bed. If greater effort isrequired, then additional caregivers and/or useof powered transport device is recommended.

Rationale/Calculations Used forErgonomic Tool #7

Push forces were measured in Newtons (N) for eachitem of equipment listed in Table 2. Initial forceswere measured as the peak force to initially propelthe item. Sustained force was measured as the mini-mum force required to maintain equipment propul-

sion. Initial-wheels turned were measured as thepeak initial force where the wheels on the equipment

Equipment Type of ForceTrial1(N)

Trial2(N)

Trial3(N)

Trial4(N)

Trial5(N)

Mean(N)

Mean(lbF)

Max PushDistance (ft)

Electrosurgi-cal unit

initial force 30 35 35 30 30 32.0 7.2 >200

sustained force 10 10 10 10 10 10.0 2.2 >200

initial-wheels turned 40 35 37.5 8.4 >200

OR stretcher,unoccupied

initial force 62 70 65 75 68.0 15.3 >200

sustained force 20 20 25 25 25 23.0 5.2 >200


OR stretcher,occupied,300 lbs

initial force 120 120 120 115 120 119.0 26.8 >200

sustained force 30 35 30 40 40 35.0 7.9 >200

initial-wheels turned 210 180 195.0 43.8 200

sustained force 30 25 30 25 27.5 6.2 >200


Bed, occu-pied, 300 lbs

initial force 170 160 167 135 155 157.4 35.4 >200

sustained force 40 50 50 40 60 48.0 10.8 >200

initial-wheels turned 230 215 222.5 50.0


26/36



Equipment Type of ForceTrial1(N)

Trial2(N)

Trial3(N)

Trial4(N)

Trial5(N)

Mean(N)

Mean(lbF)

Max PushDistance (ft)

Specialty ORbeds, unoc-cupied

initial force 175 182 190 260 200 201.4 45.3 200


X-ray equip-ment, C-arm

initial force 100 75 100 75 85 87.0 19.6 >200sustained force 20 25 25 25 25 24.0 5.4 >200

initial-wheels turned n/a n/a n/a n/a n/a

X-ray equip-ment, portable

initial force 60 55 55 60 58 57.6 12.9 >200

sustained force 25 30 30 30 30 29.0 6.5 >200

initial-wheels turned n/a n/a n/a n/a n/a

Video towers initial force 35 40 40 35 35 37.0 8.3 >200

sustained force 15 20 20 15 20 18.0 4.0 >200


Ultrasound initial force 35 40 45 45 40 41.0 9.2 >200

sustained force 20 20 25 20 20 21.0 4.7 >200


Specialtyequipmentcarts

initial force 105 90 120 125 145 117.0 26.3 >200

sustained force 25 30 30 25 25 27.0 6.1 >200

initial-wheels turned 165 185 175.0 39.3 200

sustained force 20 25 20 25 20 22.0 4.9 >200


MEASURED PUSH FORCES FOR OPERATING ROOM EQUIPMENT

Table 2, continued


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were turned perpendicular to the desired direction of

travel. The average force measured across fiverepeated trials for each condition and equipmentitem was computed and converted into US units.

Maximum pushing distances were determinedand reported in Table 2, based on Liberty Mutualspush force limits.34 The shortest acceptable push dis-tance, considering both initial and sustained forces,was accepted (see Table 3). These values are basedon the operator with his or her hands positioned ata middle push point of 3 ft (0.92 m) from the flooror above and performing a task no more frequentlythan once every 30 minutes.

Measuring Pushing/Pulling ForcesTo measure OR equipment not listed in Table 2, ameasuring device can be applied to measure appli-cable pushing/pulling forces. Commercially avail-able measuring instruments can be used to meas-ure push/pull forces (eg, strain gage, force meters,precision springs). A simple low-cost method formeasuring the required forces for pushing orpulling objects, such as beds, carts, and transferequipment, is shown in Figure 1. As illustrated, abroom handle or other lightweight cylindrical

object can be taped to a bathroom scale and usedto measure push forces. Required pull forces wouldbe identical to the required pushing force. Thescale is placed against the object to be pushed anda force is then slowly applied to the handle untilthe object moves. The maximum required pushingforce is read off the weight scale. The scale shouldprovide a continuous readout of applied force toobtain the maximum value. To obtain the best esti-mate of the actual maximum force, the measure-

ment should be repeated several times and theaverage value should be used for assessment. Thisforce can then be compared to the maximum rec-ommended push force values shown in Table 3.For example, assume that the force required topush a cart was measured to be 60 lbs. Accordingto Table 3, this task would not be acceptable forone caregiver for any distance, but would be

acceptable for two caregivers (assuming eachpushed 26 lbs) for a distance of up to 25 feet. Apowered transport device would be recommendedif one caregiver is performing the task.

Other Background Materials

The Revised NIOSH Lifting EquationThe Revised NIOSH Lifting Equation (RNLE) providesa mathematical equation for determining the recom-mended weight limit (RWL) and lifting index (LI) forselected two-handed manual lifting tasks. The RWL is

the principal product of the RNLE and is defined fora specific set of task conditions and represents theweight of the load that nearly all healthy workerscould perform over a substantial period of time (eg,up to 8 hours) without an increased risk of develop-ing lifting-related low back pain. By healthy work-ers, NIOSH means workers who are free of adversehealth conditions that would increase their risk ofmusculoskeletal injury.

The concept behind the RNLE is to start with arecommended weight that is considered safe for anideal lift (ie, load constant equal to 51 pounds or

23 kg) and then reduce the weight as the task

Push/Pull Forces Based on 75%Acceptable for Women Design Goal

Distance (ft) 25 50 100 150 200

Initial (lbs) 51 44 42 42 37

Sustained(lbs)

30 25 22 22 15

Adapted from Manual Materials Handling Guidelines, http://

libertymmhtables.libertymutual.com/CM_LMTablesWeb/pdf/LibertyMutualTables.pdf. Reprinted with permission fromthe Liberty Mutual Research Institute for Safety.

PUSH FORCE LIMITS

Table 3

Figure 1. Simple device for measuring required

push force. Photo by Tom Waters, PhD, CPE.


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becomes more stressful (ie, as the task-related factorsbecome less favorable). The RWL equation consistsof a fixed load constant of 51 lbs that is reduced bysix factors related to task geometry (ie, location of theload relative to the worker at the initial liftoff and set-down points), task frequency and duration, and typeof handhold on the object. Assessment of patienthandling tasks was specifically excluded as a restric-tion for use of the RNLE due to limitations in the dataused to derive the equation. For some patient han-dling tasks, however, where the person being lifted isnoncombative or where there is little or no move-ment of the patient during the lifting task, the RNLEmay be applicable, and it should be possible todetermine whether the lift exceeds the RWL for thosetasks. For example, the RNLE was used to derive the35-lb weight limit for patient lifting in the VA andAORN ergonomic tools.52 The precise formulation ofthe revised lifting equation for calculating the recom-mended weight limit is based on a multiplicativemodel that provides a weighting (ie, multiplier) foreach of six task variables, which include the horizontal distance of the load from the

worker (H), vertical height of the lift (V), vertical displacement during the lift (D), angle of asymmetry (A), frequency (F) and duration of lifting, and quality of the hand-to-object coupling (C).The weightings are expressed as coefficients that

serve to decrease the load constant, which repre-

sents the maximum RWL to be lifted under idealconditions. For example, as the horizontal distancebetween the load and the worker increases, the rec-ommended weight limit for that task would bereduced from the ideal starting weight (see Table 4).

The term task variables refers to the measurabletask-related measurements that are used as input datafor the formula (ie, H, V, D, A, F, C), whereas the termmultipliersrefers to the reduction coefficients in theequation (ie, HM, VM, DM, AM, FM, CM).

The following list briefly describes the measure-ments required to use the RNLE. Details for each ofthe variables are presented later in this chapter (seesection entitled Obtaining and using the data).

H = Horizontal location of hands from midpointbetween the inner ankle bones. This is measured incentimeters or inches at the origin and the destina-tion of the lift.

V= Vertical location of the hands from the floor.This is measured in centimeters or inches at theorigin and destination of the lift.

D = Vertical travel distance in centimeters or inchesbetween the origin and the destination of the lift.

A = Angle of asymmetry; angular displacement ofthe load from the workers sagittal plane. This is meas-ured in degrees at the origin and destination of the lift.

F = Average frequency rate of lifting measured inlifts/min. Duration is defined as follows: short-dura-tion (< 1 hour); moderate-duration (> 1 but < 2hours); or long-duration (> 2 but < 8 hours), assum-ing appropriate recovery allowances (see Table 5).

Variable Metric US Customary

LC = Load Constant = 23 kg 51 lbs

HM = Horizontal Multiplier = (25/H) (10/H)

VM = Vertical Multiplier = 1-(.003V-75) 1-(.0075V-30)

DM = Distance Multiplier = .82 + (4.5/D) .82 + (1.8/D)

AM = Asymmetric Multiplier = 1-(.0032A) 1-(.0032A)

FM = Frequency Multiplier = From Table 5 From Table 5

CM = Coupling Multiplier = From Table 6 From Table 6

The recommended weight limitis defined as follows:

RWL = LC x HM x VM x DM xAM x FM x CM

Where:

RECOMMENDED WEIGHT LIMIT

Table 4


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C =Quality of hand-to-object coupling (qualityof interface between the worker and the load beinglifted). The quality of the coupling is categorized asgood, fair, or poor, depending upon the type andlocation of the coupling, the physical characteris-tics of load, and the vertical height of the lift (seeTable 6).

The LI is a term that provides a relative estimateof the level of physical stress associated with a par-ticular manual lifting task. The estimate of the levelof physical stress is defined by the relationship ofthe weight of the load lifted and the RWL.

The LI is defined by the following equation:

LI = ______Load weight_______ = _L_Recommended Weight Limit RWL

Where Load weight (L) = Weight of theobject lifted (lbs or kg).

According to NIOSH, the lifting indexmay be used to identify potentially haz-ardous lifting jobs or to compare the rela-tive severity of two jobs for the purposeof evaluating and redesigning them. From

the perspective of NIOSH, it is likely thatlifting tasks with a lifting index > 1.0 posean increased risk for lifting-related lowback pain for some fraction of the workforce.49 Lifting jobs should be designed toachieve a lifting index of 1.0 or lesswhenever possible. Some experts believethat worker selection criteria may beused to identify workers who can per-form potentially stressful lifting tasks (ie,lifting tasks that would exceed a liftingindex of 1.0) without significantly

increasing their risk of work-relatedinjury above the baseline level.49,50 Thosewho endorse the use of selection criteriabelieve that the criteria must be based onresearch studies, empirical observations,or theoretical considerations that include

job-related strength testing and/or aero-bic capacity testing.

Even these experts agree, however,that many workers will be at a signifi-cant risk of a work-related injury whenperforming highly stressful lifting tasks

(ie, lifting tasks that would exceed a lift-

ing index of 3.0). Informal or natural selectionof workers may occur in many jobs that requirerepetitive lifting tasks. According to some experts,this may result in a unique workforce that may beable to work above a lifting index of 1.0, at least intheory, without substantially increasing their risk oflow back injuries above the baseline rate of injury.

To gain a better understanding of the rationale forthe development of the recommended weight limitsand lifting index, the Revised NIOSH Equation forthe Design and Evaluation of Manual Lifting Tasksprovides a discussion of the criteria underlying thelifting equation and of the individual multipliers.49

This article also identifies both the assumptions anduncertainties in the scientific studies that associatemanual lifting and low back injuries. For moredetailed information about how to use the RNLE, thereader should consult the Applications Manual forthe Revised NIOSH Lifting Equation.50

FrequencyLifts/min

(F)

Work Duration

< 1 Hour > 1 but < 2 Hours > 2 but < 8 Hours

V < 30 V > 30 V < 30 V > 30 V < 30 V > 30

0.2 1.00 1.00 .95 .95 .85 .85

0.5 .97 .97 .92 .92 .81 .81

1 .94 .94 .88 .88 .75 .75

2 .91 .91 .84 .84 .65 .65

3 .88 .88 .79 .79 .55 .55

4 .84 .84 .72 .72 .45 .45

5 .80 .80 .60 .60 .35 .35

6 .75 .75 .50 .50 .27 .27

7 .70 .70 .42 .42 .22 .22

8 .60 .60 .35 .35 .18 .18

9 .52 .52 .30 .30 .00 .15

10 .45 .45 .26 .26 .00 .13

11 .41 .41 .00 .23 .00 .00

12 .37 .37 .00 .21 .00 .00

13 .00 .34 .00 .00 .00 .00

14 .00 .31 .00 .00 .00 .00

15 .00 .28 .00 .00 .00 .00

>15 .00 .00 .00 .00 .00 .00

FREQUENCY MULTIPLIERS

Table 5


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Glossary

Air-assisted lateral transfer device: A mattressthat is inflated with air by a portable air supply,thus facilitating a smoother lateral transfer.

Anti-fatigue mats: A special mat designed withfriction-reduction properties, used for workers whostand for long periods of time.

Anti-fatigue technique: Any technique that willreduce fatigue experienced by the worker.

Assistive devices/technology: Equipment that

can be used to take all or a portion of a load suchas the weight of a body part, off of the person per-forming a high risk task.

Clinical tools: A standardized process or set ofrules by which a provider makes decisions about acomplex process (eg, which equipment and tech-niques to use when performing high-risk patienthandling and movement tasks).

Compressive force: Mechanical force directedalong the Y (ie, vertical) axis, brought about by thecombined effect of internal and external load bearing.

Ergonomics: Applied science of designing and

arranging things for people to use efficiently andsafely; matching job tasks to workers capabilities.Ergonomist: A practitioner in the field of

ergonomics.Friction-reducing devices: Low-friction (slippery)

material assistive aids for lateral transfer of patients.Lateral position: Side-lying.Lateral transfer: Movement of a patient in a

supine position on a horizontal plane, such astransferring a patient from a bed to a stretcher.

Lateral transfer device: A device that is used tomove a patient from one surface to another while

in a supine position.

lbF: A unit of force equal to the mass of 1 pound

with an acceleration equal to 1 gravitational con-stant (32 ft/s2) Acceleration due to gravity (g) equals9.8 meters per second squared (9.8 m/s2) or 32 feetper second squared (32 ft/s2).

Lifting index: Relative estimate of physical stressassociated with one specific task. It is equal to theload of the object/recommended weight limit.

Lithotomy position: Supine position with the

Documents

A Orn Guidance Statement