Thromboprophylaxis Physical

8/6/2019 Thromboprophylaxis Physical

http://slidepdf.com/reader/full/thromboprophylaxis-physical 1/28



• Learn to discuss the special anesthesiological needs of OS patients at risk for DVT, with a focus on timing of prophylaxis, transitioning agents, and duration of prophylaxis based on the surgical procedure.

•• Describe how to risk stratify patients undergoing

orthopedic surgery, and implement ACCP-mandatedpharmacologic and non-pharmacologic measuresaimed at DVT prophylaxis.

•• Learn how to apply landmark clinical trials focusing on

DVT prevention in OS patients.•

Educational Objectives



DVT Prophylaxis After THAProphylaxis: No

Warwick, JBJS, Br, 1995• 1162 THA• No chemical prophylaxis

• Fatal PE 0.34%

, ,M u rra y e t a l JB JS B r 1 9 9 6, ,M u rra y e t a l JB JS B r 1 9 9 6

► -M e ta a n a ly sis-M e ta a n a ly sis

► ,1 3 0 0 0 0 T H A,1 3 0 0 0 0 T H A

► . - . %R e p o rte d fa ta l P E 0 1 0 2. - . %R e p o rte d fa ta l P E 0 1 0 2



The absolute risk of DVT is high inpatients who sustain a fracture of thehip, spine, pelvis, or lower extremity

Risks of VTE in orthopedic trauma and fracture surgery

Condition DVT % PE %

Total Proximal

Total Fatal

Hip fracture [25] 40–64 23–41 1–11 1–7.5

Polytrauma [16] 29–63 8–32 6–7 0.1–1

Spinal cord injury [31] 47–90 17–35 5–11 0–0.8

Pelvic or acetabular fractures [17, 18]

10–61 10–29 2–8 0.5–2

Isolated lower extremity

fracture [20]

17–45 1–8 1–5 1



• Compression stockingsGraduated compression stockings have not been formally tested in trauma patients.Nevertheless, many surgeons recommend combining graduated compression stockingswith pharmacological methods for VTE prophylaxis in trauma patients. Mechanical pumpsVarious compression devices exist to replace or enhance the natural muscle pumpfunction. These include the venous foot pumps developed to mimic the effect of weightbearing and sequential pneumatic compression devices that transport venous bloodproximally. Generally, mechanical pumps appear to be beneficial in reducing VTE in hipfracture patients. However, their use in trauma patients has not been shown to bebeneficial in DVT prevention compared with no prophylaxis [22]. Their use isrecommended in patients where anticoagulation is contraindicated. Vena cava filtersFilter placement is a strategy for the prevention of PE in the face of known or likelythrombosis. Its role in trauma surgery and the risks and benefits of placing the filterprophylactically are not yet fully clear.

• Filters are recommended in very high-risk trauma patients

who cannot receive anticoagulation because of increasedbleeding risk [18].

• There are retrievable ones and nonretrievable ones. A serious long-term complication of inferior vena cava filtration is thrombotic occlusion of the inferior vena cava (IVC) (in 6%to 30% of cases). Retrievable filters can be considered in younger trauma patients inwhom contraindications to anticoagulation are expected to be temporary [23].

•



Thromboprophylaxis RegimensThromboprophylaxis Regimens

►Mechanical• ( )Graduated Compression Stockings GCS

• ( )Intermittent Pneumatic Compression IPC

►Anticoagulants

• -Low Dose Unfractionated Heparin( )LDUH

• - -Low Molecular Weight Heparin( / )LMWH fondaparinux

• - - ( )Vitamin K Antagonists VKA



• Pharmacologic agents – Unfractionated heparin

– LMWH

– Coumadin

– Aspirin

• Mechanical • Multimodal

DVT Prophylaxis After TJAObjectives



• System functions as a prophylaxis for deep veinthrombosis by using an effective combinationof graduated sequential compression and rapidimpulse inflation. This unique collaboration of

technology increases venous velocity whileenhancing fibrinolysis, thus assisting in theprevention of thrombus formation



• The cuffs are latex-free and may be placed directly against the skin.Each cuff style is designed for single patient use only.1) Calf cuff length is 11.5" (29 cm)2) Thigh cuff length is 21.0" (53 cm)3) Foot cuff length is 9" (23 cm)

• Tube assemblies are included with the Vena Flow pump and areavailable in three lengths 5.5", 8.5" and 10.5".

• Rapid inflation combined with graduated sequential compression results in adramatic increase in venous velocity

• Universal pump design is compatible with all three cuff styles (calf, foot and thigh) tominimize inventory

• Asymmetric compression for superior emptying of veins

• Light, cool, latex-free cuffs help promote patient compliance• Preset alarms and patient counter available for ease of use





• Historic 1 - 2%

• Current 0.1 - 0.2%

. .Fa ta lP E. .Fa ta l P E

DVT Prophylaxis After THAImportance



• In many cases thecomplication ispreventable

• We (not the internists) areresponsible for choosing

and administeringprophylaxis

DVT Prophylaxis After THAImportance



Data Difficult to Interpret:• Different methods of diagnosis

– clinical - ultrasound – venography - scans

• Different endpoints – death - DVT proximal vs

distal – clinical PE or DVT

• Different definitions of complications

– bleeding: major, minor – post phlebitic syndrome

DVT Prophylaxis After THAIntroduction



“Effective prophylaxis isnecessary in these patients

[THA, TKA] . . .”

• NIH consensus panel, 1986• European consensus

conference 1992

DVT Prophylaxis After THAProphylaxis: Yes



• 434 surgeons representing48 states and threecountries (Canada, Egypt,Pakistan)

• Surgeons have been inpractice an average of 19

years•

• >96% prophylax for DVT intheir THA and TKA patients

•

OREF Survey



OREF Survey





Ris or Heparin In uce T rom ocytopenia wits or epar n n uce rom ocytopen a w t



-Ris or Heparin In uce T rom ocytopenia wit-s or epar n n uce rom ocytopen a w t-Unfractionated and Low Molecular Weight Heparin-Unfractionated and Low Molecular Weight Heparin

: -Thromboprophylaxis A Meta Analysis: -Thromboprophylaxis A Meta Analysis

► - ( )Heparin induced thrombocytopenia HIT is an uncommon but- ( )Heparin induced thrombocytopenia HIT is an uncommon but potentially devastating complication of anticoagulation with potentially devastating complication of anticoagulation with

( ) - -unfractionated heparin UFH or low molecular weight heparin( ) - -unfractionated heparin UFH or low molecular weight heparin

( )LMWH( )LMWH► –The inverse variance weighted average that determined the–The inverse variance weighted average that determined the

. %,absolute risk for HIT with LMWH was 0 2 and with UFH the. %,absolute risk for HIT with LMWH was 0 2 and with UFH the

. %.risk was 2 6 Most studies were of patients after orthopedic. %.risk was 2 6 Most studies were of patients after orthopedic surgery surgery

►

.Martel et al Blood 2005 ; : -106 2710 15



►Wide variety of devices – foot pump – calf – thigh-calf

►

►Each device has its own mechanicswith resultant change in peakvenous velocity and venous volume

►

►For THA, optimal characteristics of pneumatic compression are notknown

Mechanical Prophylaxis THA Mechanical Prophylaxis THA



Venous Hemodynamics After THA

►Devices with rapid inflationtime

–Produced the greatest

increase in peak venousvelocity

►Devices that compress calf

and thigh –Produced the greatest

increase in venous volume

r opae s s oncerns



r opae s s oncernsAnticoagulation TKA

• Increased risk of major bleeding intoknee and wound complications (0.9 –5.2%)

• True risk of bleeding and outcomenot established for all TKA patients

• Bleeding into TKA associated withhematomas, drainage, infectionand poorer outcomes



Mechanical Prophylaxis TKA

• Wide variety of devices – thigh-calf – calf only – foot pump

• Each device has its own mechanicswith different changes in peakvenous velocity and volume

• Optimal characteristics for devices?



Venous Hemodynamics After TKA

. Westrich et al ( ) JBJS B 1998

Flowtron DVTVenaFlowPlexiPulse-foot calf

PlexiPulsefoot

-A V impulsesystem

DPF Jobstathrombic

pump

SCD system

-Calf thighCalfFoot calfFoot

( % )

I n c r e a s e

i n

v e r

i o

u s

v e

l o c

i t

y

wo ec an ca ev ces or



wo ec an ca ev ces orProphylaxis

of Thromboembolism After TKA,Prospective randomized study,Prospective randomized study,Prospective randomized study,Prospective randomized study



Results

Asymmetrical Circumferential Compression Compression Patients 206 217

Knees 232 240Mortality 0 1 (.46%)

Pulm. Embolism 0 1 (.46%)

Thrombi 16 (6.9%) 36 (15%) p = .007 Calf 15 30 Proximal 1 6



Overview

• Venous thromboembolism (VTE),DVT and PE are real andsignificant threats to theorthopedic patient

• The anesthesia and analgesiaplan must accommodatetreatment of VTE

• Anesthesia and pain

management can bechallenging and pose risks tothe patient in the absence of communication andcooperation between careteams



Documents

Thromboprophylaxis Physical