Peri-operative Peri-operative Assessments, Pain, Fever, Assessments, Pain, Fever,

Oliguria and DVT Oliguria and DVT ProphylaxisProphylaxis

Peter E. Rice, MD Peter E. Rice, MD Surgical Fundamentals Session #4Surgical Fundamentals Session #4

ALGORITHMS

Pre-operativeAssessment Fever Oliguria PainDVT Prophylaxis

What are the specific pre-operative laboratory tests and/or evaluations that should be performed to confirm or to rule out medical conditions that are likely to impact a patient’s perioperative course?

Question:

> 3 billion dollars are spent each year on pre-op lab evaluations- and > 60% of these are unnecessary

From the Anesthesiologists Point of View………….From the Anesthesiologists Point of View………….

ClassClass Physical StatusPhysical Status 48 hr mortality48 hr mortalityII No systemic diseaseNo systemic disease 0.07%0.07%

IIII Mild systemic disease; no functional Mild systemic disease; no functional limitation (obese, smoker, HTN)limitation (obese, smoker, HTN)

0.24%0.24%

IIIIII Severe, not incapacitating systemic Severe, not incapacitating systemic disease (CAD, CHF, COPD)disease (CAD, CHF, COPD)

1.4%1.4%

IVIV Incapacitating disease that is a Incapacitating disease that is a constant threat to lifeconstant threat to life

7.5%7.5%

VV Moribund pt. not expected to survive Moribund pt. not expected to survive 24 hrs regardless of surgery24 hrs regardless of surgery

8.1%8.1%

EE Suffix added to classSuffix added to class(emergency)(emergency)

Doubles riskDoubles risk

ASA I

18-39 yrNo labs

Females Preg Test

40-59 yrEKG

Females Preg Test

>60yoSMA-7CXREKG

Lab Tests <35 days acceptable w/o change in condition

CXR <6 months

EKG <2 months

Urine pregnancy on day of surgery

ASA II

Laboratory tests as required byASA I patients and tests as

indicated by the patient’s specificdisease states

CXR in all patients >20 pk-yrsmokers

ASA III

CBC

SMA-12

U/A

CXR

EKG

Upreg

Consult from an appropriate physician

Tests as indicated by the patient’s specific disease state

Tests as Indicated by the Disease State…..Tests as Indicated by the Disease State…..

Systems Assessment

CNS

Pulmonary

GI

Heme/Onc

Medications

Seizure/stroke

PFT’s, ABG, Bronchodilators, Steroids

Liver dz

Renal CBC, Lytes

CBC,INR,PT,PTT

Tests as indicated by the patient’s specific disease state

And the risk of the planned procedure

The History and Physical will uncover the clinical risk of the patient

Hx/PE

?Cardiac Disease-CAD,CHF,Arrhythmia,CVA, PVD

Estimate Clinical Risk

Low risk procedure

High risk procedure

Exercise Stress

Dobutamine w/ Echo

Persantine Thallium

OR

A Special Case…….

One Additional NoteOne Additional Note

Patients who are receiving beta-blockers to Patients who are receiving beta-blockers to treat angina, arrhythmias, or hypertensiontreat angina, arrhythmias, or hypertension

Patients undergoing vascular surgery who Patients undergoing vascular surgery who are at high cardiac riskare at high cardiac risk

Patients who are at increased cardiovascular Patients who are at increased cardiovascular riskrisk

advanced ageadvanced age diabetes mellitusdiabetes mellitus renal insufficiencyrenal insufficiency

Perioperative Beta-Blocker Therapy

Fever is a common event but cannot be ignored

Two temperature elevations >38.5 in a 24-hour period

Postoperative Fever T>38.5

Early <48 hours Late >48 hours

Both evaluations begin with History and Physical Exam

•The cause of most postoperative fevers will be elucidated by the history and physical

•Check the comorbidities- transfusion, meds, malignancy, FB, diabetes

•Always check the operative site

Early <48 hours

Physical exam

Wind

Wound

Water

Walk

Wonder Drugs

Late >48 hours Physical Examination

Wound

Respiratory

IV sites

GU

Intra-abdominal

Extremity swelling

cellulitis

drainage

CXR ?AIE

?infected

UA /CX

CT Scan

Duplex

Oliguria

OliguriaAcute oliguria is the excretion of <400cc of urine per day, and is often the earliest sign of impaired renal function

Classification ofAcute Renal

Failure

Prerenal(50%-90% of total cases)Volume depletion

DehydrationHemorrhage

Fluid redistributionCardfiac Failure

Systemic vasodilatationRenovascular obstructive disease

Renal Parenchymal(10-30%)ATN

IschemiaNephrotoxins

GlomerulonephritisVasculitides

Interstitial nephritis

Postrenal(1%-15% of total cases)Obstructive uropathy

Renal pelvis and uretersBladder and urethra

Extravasation

Patient presentswith signs of oliguria

urine output<.5cc/kg/hr

Clinical assessment:Vitals

Check the ChartPhysical ExamUrinary tractobstruction

Administer I.V. fluidchallenge (~10%

circulating volume)isotonic crystalloid

? blood

Urine outputimproves- continue

to monitor

Renal parenchymaldysfunction (UNa>40

mEq/L or FENa>3Stop nephrotoxic drugs

if possibleAvoid contrast agents

Consider loop diuretics

Prerenal dysfunction(UNa<20mEq/L orFENa<1)

Expand intravascular volumeMonitor CVP,PAWP,

?acute renal arterial problems?abdominal compartment

syndrome?CHF

?sepsis

Renal Functionreturns to normal

Continuemonitoring. Avoidhypovolemia and

use of nephrotoxicagents

Renal dysfunctioncontinues orprogresses

Adjust medicationsand fluids

?Renal replacementtherapy CVVH

Renal deteriorationstops or slows

Chronic renal failureensues

Urine output does not resolveRe-evaluate

Administer second IV fluid challenge?CVP

Calculate FENaUrine and Plasma electrolytes

68yo male s/p LAR with loop ileostomy T 37 P 110 BP 110/75 R12 UO 14cc in the last hour

Fe NA = Urine [Na] / Plasma [Na]

Urine [Cr] / Plasma [Na]x100

FeNa < 1% prerenal

FeNa > 2% renal (ATN)

Urinary sodium (meqL) <20 prerenal

>40 renal

Venous ThromboembolismVenous Thromboembolism

DVT

Pulmonary Embolus

National Body Position Statements

o Leapfrog1: • PE is “the most common preventable cause of hospital death in the United States”• Agency for Healthcare Research and Quality (AHRQ)2: Thromboprophylaxis is the number 1 patient safety practice• American Public Health Association (APHA)3: “The disconnect between evidence and execution as it relates to DVT prevention amounts to a public health crisis.”

1. The Leapfrog Group Hospital Quality and Safety Survey. Available at: www.leapfrog.medstat.com/pdf/Final/doc

2. Shojania KG, et al. Making Healthcare Safer: A Critical Analysis of Patient Safety Practices. AHRQ, 2001. Available at: www.ahrq.gov/clinic/ptsafety/

3. White Paper. Deep-vein thrombosis: Advancing awareness to protect patient lives. 2003. Available at: www.alpha.org/ppp/DVT_White_Paper.pdf

Rationale for DVT Rationale for DVT ProphylaxisProphylaxis

High Prevalence of DVTHigh Prevalence of DVT Adverse Consequences of DVTAdverse Consequences of DVT Efficacy and effectiveness of Efficacy and effectiveness of

thromboprophylaxisthromboprophylaxis Highly efficacious in prevention of DVTHighly efficacious in prevention of DVT Highly efficacious in prevention of symptomatic DVT Highly efficacious in prevention of symptomatic DVT

and fatal PEand fatal PE DVT prevention prevents PEDVT prevention prevents PE Cost effectiveness has been demonstratedCost effectiveness has been demonstrated

Absolute Risk of DVT in Absolute Risk of DVT in Hospitalized PatientsHospitalized Patients

Patient GroupPatient Group DVT Prevalence, %DVT Prevalence, %Medical patientsMedical patients 10-2010-20General surgeryGeneral surgery 15-4015-40Major GYN surgeryMajor GYN surgery 15-4015-40Major GU surgeryMajor GU surgery 15-4015-40NeurosurgeryNeurosurgery 15-4015-40StrokeStroke 20-5020-50Hip or Knee surgeryHip or Knee surgery 40-6040-60Major TraumaMajor Trauma 40-8040-80Spinal Cord InjurySpinal Cord Injury 60-8060-80Critical Care patientsCritical Care patients 10-8010-80

Thromboprophylaxis Reduces Thromboprophylaxis Reduces DVT EventsDVT Events

Pulmonary Embolus is the most common Pulmonary Embolus is the most common preventable cause of hospital deathpreventable cause of hospital death

Risk Factors for DVTRisk Factors for DVT SurgerySurgery TraumaTrauma Immobility, paresisImmobility, paresis MalignancyMalignancy Cancer therapyCancer therapy Previous VTEPrevious VTE Increasing ageIncreasing age Pregnancy and postpartumPregnancy and postpartum Estrogen-containing oral Estrogen-containing oral

contraception or HRTcontraception or HRT Selective estrogen receptor Selective estrogen receptor

modulatorsmodulators Acute medical illnessAcute medical illness

Heart or respiratory failureHeart or respiratory failure Inflammatory bowel diseaseInflammatory bowel disease Nephrotic syndromeNephrotic syndrome Myeloproliferative disordersMyeloproliferative disorders Paroxysmal nocturnal Paroxysmal nocturnal

hemoglobinuriahemoglobinuria ObesityObesity Smoking Smoking Varicose veinsVaricose veins Central venous Central venous

catheterizationcatheterization Inherited or acquired Inherited or acquired

thrombophiliathrombophilia

MethodsMethods of Prophylaxisof Prophylaxis Mechanical MethodsMechanical Methods

Graduated Compression StockingsGraduated Compression Stockings Intermittent Pneumatic Compression deviceIntermittent Pneumatic Compression device Venous foot pumpVenous foot pump

StudiesStudies Not blindedNot blinded High rate of false negative scansHigh rate of false negative scans Compliance in true practice – poorCompliance in true practice – poor

Acceptable optionAcceptable option High risk for bleeding High risk for bleeding Adjunct to anticoagulant prophylaxisAdjunct to anticoagulant prophylaxis

Improves efficacy when used in combination with anticoagulant Improves efficacy when used in combination with anticoagulant prophylaxisprophylaxis

AnticoagulantsAnticoagulants Most widely used and studied prophylaxisMost widely used and studied prophylaxis Before 1987, only heparin and warfarin were availableBefore 1987, only heparin and warfarin were available Now,Now,

4 low molecular weight heparins4 low molecular weight heparins1 Factor Xa inhibitor1 Factor Xa inhibitor3 direct thrombin inhibitors3 direct thrombin inhibitors1 coumarin derivative1 coumarin derivative

Unfractionated HeparinUnfractionated Heparin

Potentiates inactivation of Potentiates inactivation of activated enzymes of activated enzymes of clotting cascade, via clotting cascade, via binding to antithrombin IIIbinding to antithrombin III

Effective in preventing DVT Effective in preventing DVT in low and moderate risk in low and moderate risk patientspatients

Does not increase risk of Does not increase risk of hemorrhagehemorrhage

Low Molecular Weight HeparinLow Molecular Weight Heparin

Higher bioavailability; stable and Higher bioavailability; stable and predictable antithrombotic predictable antithrombotic activityactivity

Can be administered once-dailyCan be administered once-daily

Lower risk of thrombocytopeniaLower risk of thrombocytopenia

More effective for high risk More effective for high risk prophylaxis than heparinprophylaxis than heparin

General SurgeryGeneral Surgery 46 RCT Low Dose Unfractionated Heparin 46 RCT Low Dose Unfractionated Heparin

v. placebo or no proph.v. placebo or no proph. Reduced Reduced

DVT 22 to 9%DVT 22 to 9% Symptomatic PE 2 to 1.3%Symptomatic PE 2 to 1.3% Fatal PE 3 to .8%Fatal PE 3 to .8%

Meta-analysis Meta-analysis No increase in wound hematoma or bleedingNo increase in wound hematoma or bleeding

General SurgeryGeneral Surgery LMWH (LMWH (LovenoxLovenox))

Meta-analysis Meta-analysis (Douketis Arch Intern Med (Douketis Arch Intern Med 2002)2002) 70 % reduction DVT v. no prophylaxis70 % reduction DVT v. no prophylaxis

Nine meta-analysis and systematic reviewsNine meta-analysis and systematic reviews No difference in DVT LMWH and UFHNo difference in DVT LMWH and UFH Some trials fewer hematomas and bleeding Some trials fewer hematomas and bleeding

complications with LMWHcomplications with LMWH No difference in total mortality, fatal PE between No difference in total mortality, fatal PE between

LDUH 5000 units TID and LMWHLDUH 5000 units TID and LMWH

General SurgeryGeneral Surgery Low RiskLow Risk

Minor Surgery (hernia repair, outpatient Minor Surgery (hernia repair, outpatient surgery)surgery)

< 40 years of age< 40 years of age No additional risk factorsNo additional risk factors

RiskRisk DVT DVT Calf – 2%Calf – 2% Proximal – 0.4%Proximal – 0.4% PEPE Clinical – 0.2%Clinical – 0.2% Fatal - <0.01%Fatal - <0.01%

Prevention StrategiesPrevention Strategies No specific prophylaxis; early mobilizationNo specific prophylaxis; early mobilization

General SurgeryGeneral Surgery Moderate RiskModerate Risk

Minor Surgery with additional risk factorsMinor Surgery with additional risk factors Age 40-60 with no risk factorsAge 40-60 with no risk factors Major surgery, < 40 with no risk factorsMajor surgery, < 40 with no risk factors

RiskRisk DVTDVT Calf - 10-20%Calf - 10-20% Proximal - 2-4%Proximal - 2-4% PEPE Clinical - 1-2%Clinical - 1-2% Fatal - 0.1-0.4 %Fatal - 0.1-0.4 %

Prevention StrategiesPrevention Strategies LDUH (5,000 units q 12 hours, start 1-2 hrs pre-op)LDUH (5,000 units q 12 hours, start 1-2 hrs pre-op) LMWH ( 30mg daily)LMWH ( 30mg daily)

Graduated Compression StockingsGraduated Compression Stockings Intermittent Pneumatic Compression DevicesIntermittent Pneumatic Compression Devices

General SurgeryGeneral Surgery High RiskHigh Risk

Non-major surgery in age > 60 yr. or have additional Non-major surgery in age > 60 yr. or have additional risk factorsrisk factors

Major Surgery > 40 or have additional risk factorsMajor Surgery > 40 or have additional risk factors RisksRisks

DVTDVT Calf – 20-40%Calf – 20-40% Proximal – 4-8%Proximal – 4-8% PEPE Clinical – 2-4 %Clinical – 2-4 % Fatal – 0.4-1.0%Fatal – 0.4-1.0%

Prevention StrategiesPrevention Strategies LDUH (5,000 U q LDUH (5,000 U q 8 hours8 hours)) LMWH ( 30mg q 12h)LMWH ( 30mg q 12h)

General SurgeryGeneral Surgery Highest RiskHighest Risk

Surgery in patients with multiple risk factorsSurgery in patients with multiple risk factors RiskRisk

DVT Calf – 40-80%DVT Calf – 40-80% Proximal – 10-20%Proximal – 10-20% PE Clinical – 4-10%PE Clinical – 4-10% Fatal - 0.2 - 5%Fatal - 0.2 - 5%

Prevention StrategiesPrevention Strategies LDUH ( 5,000 q 8 hours)LDUH ( 5,000 q 8 hours)

oror LMWH ( 30mg q12h)LMWH ( 30mg q12h)

withwith GCS and/or IPCGCS and/or IPC

General SurgeryGeneral Surgery Special ConsiderationsSpecial Considerations

High Risk of BleedingHigh Risk of Bleeding Properly fitted GCS and/or IPC Properly fitted GCS and/or IPC

Major Cancer SurgeryMajor Cancer Surgery Post hospital discharge prophylaxis with LMWH for Post hospital discharge prophylaxis with LMWH for

2-3 weeks2-3 weeks

Prolonged prophylaxis in abdominal and pelvic cancer Prolonged prophylaxis in abdominal and pelvic cancer reduced DVT 12 to 5%reduced DVT 12 to 5%

Bergqvist NEJM 2002Bergqvist NEJM 2002

Vascular SurgeryVascular Surgery RiskRisk

Aortic Surgery - DVT – 0.9 - 12 %Aortic Surgery - DVT – 0.9 - 12 % No prophylaxis No prophylaxis – 41%– 41%

Femorodistal – DVT – 0.7 – 9%Femorodistal – DVT – 0.7 – 9% No No prophylaxis – 18%prophylaxis – 18%

No routine prophylaxis in patients without risk No routine prophylaxis in patients without risk factors factors

LDUH or LMWH in patients with risk factorsLDUH or LMWH in patients with risk factors

Recommendations in LaparoscopyRecommendations in Laparoscopy European Association for Endoscopic SurgeryEuropean Association for Endoscopic Surgery

Intraoperative IPC for all prolonged laparoscopic Intraoperative IPC for all prolonged laparoscopic proceduresprocedures

SAGESSAGES Same thromboprophylaxis options with Same thromboprophylaxis options with

laparoscopic procedures as for the equivalent laparoscopic procedures as for the equivalent open surgical proceduresopen surgical procedures

ACCPACCP No risk factors – aggressive early mobilization No risk factors – aggressive early mobilization

With risk factors – LDUH, LMWH, IPC or GCSWith risk factors – LDUH, LMWH, IPC or GCS

Major TraumaMajor Trauma Highest Risk of all Hospitalized PatientsHighest Risk of all Hospitalized Patients Risk – without Rx exceeds 50%Risk – without Rx exceeds 50%

DVT Calf – 40-80%DVT Calf – 40-80% Proximal – 10-20%Proximal – 10-20% PE Clinical – 4-10%PE Clinical – 4-10% Fatal - 0.2 - 5%Fatal - 0.2 - 5%

Risk with routine thromboprophylaxisRisk with routine thromboprophylaxis DVT Calf – 27%DVT Calf – 27% Proximal – 7%Proximal – 7%

Increased Risk FactorsIncreased Risk Factors Spinal Cord injury, lower extremity or pelvic Fx, need for Spinal Cord injury, lower extremity or pelvic Fx, need for

surgery, increasing age, surgery, increasing age, femoral venous linefemoral venous line insertion or insertion or major venous repair, prolonged immobility, prolonged major venous repair, prolonged immobility, prolonged ventilatory support and longer duration of hospital stay, +/- ventilatory support and longer duration of hospital stay, +/- ISSISS

Trauma RecommendationsTrauma Recommendations All patients with at least one risk factor All patients with at least one risk factor

receive thromboprophylaxisreceive thromboprophylaxis LMWH as soon as considered ‘safe’LMWH as soon as considered ‘safe’ If LMWH delayed – BootsIf LMWH delayed – Boots Continued thromboprophylaxis until mobility Continued thromboprophylaxis until mobility

adequateadequate Duplex ultrasound screening – high risk and Duplex ultrasound screening – high risk and

suboptimal prophylaxis or no prophylaxissuboptimal prophylaxis or no prophylaxis

PainPain

An unpleasant sensory and emotional An unpleasant sensory and emotional experience associated with actual or experience associated with actual or

potential tissue damage, or described potential tissue damage, or described in terms of such damage.in terms of such damage.

““Pain is whatever the Pain is whatever the experiencing person says it experiencing person says it

is and exists whenever is and exists whenever he/she says it does.”he/she says it does.”

Classes of drugsClasses of drugs

Opioid analgesicsOpioid analgesics

Nonsteroidal anti-inflammatory drugs Nonsteroidal anti-inflammatory drugs (NSAIDS) ((NSAIDS) (Aspirin, Motrin, ToradolAspirin, Motrin, Toradol))

Opioid AnalgesicsOpioid Analgesics

Schedules of Controlled Schedules of Controlled NarcoticsNarcotics

Schedule I:Schedule I: Unacceptable potential for Unacceptable potential for abuse: abuse: Heroin, Cocaine, LSDHeroin, Cocaine, LSD

Schedule II:Schedule II: High potential for abuse and High potential for abuse and dependence: dependence: opioids, amphetaminesopioids, amphetamines

Schedule III:Schedule III: Intermediate potential for Intermediate potential for abuseabuse: codeine+ acetaminophen, : codeine+ acetaminophen, hydrocodone + acetaminophenhydrocodone + acetaminophen

Schedules of Controlled Schedules of Controlled NarcoticsNarcotics

Schedule IV:Schedule IV: Less abuse potential than Less abuse potential than schedule III, minimal dependence: schedule III, minimal dependence: lorazepam alprazolam, diazepamlorazepam alprazolam, diazepam

Schedule V:Schedule V: minimal abuse potential: minimal abuse potential: codiene cough syrup, lomotilcodiene cough syrup, lomotil

ActionAction

Binds to opiate receptors in the central Binds to opiate receptors in the central nervous system. nervous system.

Alters the perception of and response to Alters the perception of and response to painful stimulipainful stimuli

Produces generalized Produces generalized CNS depressionCNS depression

CNS side effects of opioidsCNS side effects of opioids Respiratory depressionRespiratory depression Hypotension, orthostatic hypotensionHypotension, orthostatic hypotension Constipation, nausea,vomitingConstipation, nausea,vomiting Urinary retentionUrinary retention ConfusionConfusion RashRash

Contraindications & Contraindications & PrecautionsPrecautions

Contraindications:Contraindications: HypersensitivityHypersensitivity

Precautions: Precautions: ElderlyElderly Respiratory diseasesRespiratory diseases Head traumaHead trauma Liver or kidney diseaseLiver or kidney disease Opioid addictionOpioid addiction

MorphineMorphine Prototype opioid analgesicPrototype opioid analgesic Equianalgesic doses of opioidsEquianalgesic doses of opioids Indications:Indications:

Severe pain Severe pain Pulmonary edema Pulmonary edema Pain associated with myocardial infarction. Pain associated with myocardial infarction.

Morphine administration routesMorphine administration routes

Many preparations & routes:Many preparations & routes: Oral: tablets, extended release (MS Contin)Oral: tablets, extended release (MS Contin) elixir (Roxanol)elixir (Roxanol) Sublingual tablets: 10 mg, rapidly absorbedSublingual tablets: 10 mg, rapidly absorbed IMIM IV, PCAIV, PCA EpiduralEpidural

Postoperative painPostoperative pain Regular & frequent dosing intervals in Regular & frequent dosing intervals in

early postop period, then PRNearly postop period, then PRN PCA, Epidural, IVPCA, Epidural, IV Opioid Opioid ++ NSAID NSAID Switch to oral dosing when taking poSwitch to oral dosing when taking po

Medicate prior to anticipated painMedicate prior to anticipated pain Ambulation & physical therapyAmbulation & physical therapy Dressing changesDressing changes

PCA: patient controlled PCA: patient controlled analgesiaanalgesia

Self-administration of IV analgesicSelf-administration of IV analgesic Very effective Very effective Prevents delaysPrevents delays Reduces patient anxietyReduces patient anxiety

PCA dosingPCA dosing ExampleExample

Morphine PCA Morphine PCA 30mg/30ml30mg/30ml

Basal rate 1 mg/hr Basal rate 1 mg/hr Demand dose 1-2 mgDemand dose 1-2 mg Lockout 6-8 minutesLockout 6-8 minutes 4 Hour Max4 Hour Max

QUESTIONS ?