Regional Anaesthesia and Patients with Abnormalities of ... and regional anaesthe… · popularity of regional anaesthesia is on the rise but also because the use of anticoagulant

November 2013

Regional Anaesthesia and Patients with Abnormalities of Coagulation

Published byThe Association of Anaesthetists of Great Britain & IrelandThe Obstetric Anaesthetists’ Association Regional Anaesthesia UK

This guideline was originally published in Anaesthesia. If you wish to refer to this guideline, please use the following reference:

Association of Anaesthetists of Great Britain and Ireland, Obstetric Anaesthetists’ Association and Regional Anaesthesia UK. Regional anaesthesia and patients with abnormalities of coagulation. Anaesthesia 2013; 68: pages 966-72. This can be viewed online via the following URL: http://onlinelibrary.wiley.com/doi/10.1111/anae.12359/abstract

Guidelines

Regional anaesthesia and patients withabnormalities of coagulation

The Association of Anaesthetists of Great Britain& IrelandThe Obstetric Anaesthetists AssociationRegional Anaesthesia UK

Membership of the Working Party: W. Harrop-Griffiths,T. Cook,1 H. Gill, D. Hill,2 M. Ingram, M. Makris, S. Malhotra,B. Nicholls,3 M. Popat, H. Swales2 and P. Wood

1 Royal College of Anaesthetists2 Obstetric Anaesthetists’ Association3 Regional Anaesthesia UK

SummaryConcise guidelines are presented that relate abnormalities of coagula-tion, whether the result of the administration of drugs or that of path-ological processes, to the consequent haemorrhagic risks associatedwith neuraxial and peripheral nerve blocks. The advice presented isbased on published guidelines and on the known properties of anti-coagulant drugs. Four separate Tables address risks associated withanticoagulant drugs, neuraxial and peripheral nerve blocks, obstetricanaesthesia and special circumstances such as trauma, sepsis and mas-sive transfusion.

© 2013 The Authors. Anaesthesia published by John Wiley & Sons Ltd on behalf of

The Association of Anaesthetists of Great Britain and Ireland.

This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License,

which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial

and no modifications or adaptations are made.

1

....................................................................................................

This is a consensus document produced by expert members of a WorkingParty established by the Association of Anaesthetists of Great Britain &Ireland, the Obstetric Anaesthetists’ Association and Regional AnaesthesiaUK. It has been seen and approved by the elected Councils/Committees ofall three organisations.

Accepted: 4 June 2013

• What other statements are available on this topic?Guidance publications on regional anaesthesia in patients taking anti-coagulant or thromboprophylactic drugs are widely available, twowell-known guidelines having been published by the American Societyof Regional Anesthesia and Pain Medicine (ASRA) [1] or adopted bythe European Society of Regional Anaesthesia and Pain Therapy(ESRA) [2].

• Why was this guideline developed?The available published guidance focuses on neuraxial blockade inpatients receiving drug therapy specifically aimed at modifyingcoagulation, but does not address non-neuraxial regional blockade orpatients with abnormalities of coagulation for other reasons. Cur-rently available guidelines are lengthy and discursive, and do notlend themselves to use in the acute clinical setting. The remit of theWorking Party that produced these guidelines was to create a concisedocument that considered regional anaesthesia of all forms andabnormalities of coagulation of both therapeutic and pathologicalorigins.

• How does this statement differ from existing guidelines?Although based on the available guidance and on published pharma-cokinetic and pharmacodynamic data pertaining to anticoagulantdrugs, this guidance is considerably more concise.

• Why does this statement differ from existing guidelines?These guidelines were developed in order to make useful and conciseguidance available to anaesthetists in the clinical setting.

Anaesthetists are often faced with the question of whether the risks of regio-nal anaesthetic techniques are increased when performed on patients with

2 © 2013 The Authors. Anaesthesia published by John Wiley & Sons Ltd on behalf of


Anaesthesia 2013 W. Harrop-Griffiths et al. | Guidelines: patients with abnormalities of coagulation

abnormalities of coagulation and, if so, whether they are so increased thatthe techniques should be modified or avoided. This is not only because thepopularity of regional anaesthesia is on the rise but also because the use ofanticoagulant drugs in the prevention of venous thromboembolism isexpanding, as is the number of different drugs in use. The serious complica-tions of regional anaesthesia in patients without abnormalities of coagula-tion are very rare indeed [3]. For example, in the third National AuditProject (NAP3), the incidence of vertebral canal haematoma after neuraxialblockade was 0.85 per 100 000 (95% CI 0–1.8 per 100 000). The extent towhich the risk of haemorrhagic complications is increased in patients withabnormalities of coagulation is unquantifiable, but likely to be small. Therarity of the complications means that it is difficult to make accurate esti-mates of the incidence of complications related to abnormalities of coagu-lation, and therefore offering patients and clinicians advice on the basis of‘hard data’ is not possible, and is unlikely ever to become possible. Weare therefore reliant on expert opinion, case reports, case series, cohortstudies and extrapolations from drug properties such as the time taken toachieve peak plasma levels and the known half-lives of drugs.

Published clinical guidance in relation to the risk associated with regio-nal anaesthesia in patients with abnormalities of coagulation is often bin-ary. For instance, it is often said that the performance of neuraxial block ina patient with < 75 9 109.l�1 platelets is not acceptable, whereas its perfor-mance in the presence of > 75 9 109.l�1 platelets is acceptable. However,there can be no relevant difference in risk or outcome after neuraxialblockade in two patients, one of whom has a platelet count of 74 9 109.l�1

and the other 76 9 109.l�1. Risk is a continuum that runs from ‘normalrisk’ to ‘very high risk’, and this guidance seeks to emphasise this point.This guidance must be interpreted and used after consideration of anindividual patient’s circumstances. None of the advice in this guidanceshould be taken as being prohibitive or indicative. An abnormality ofcoagulation – however severe – is always a relative contraindication tothe use of a regional anaesthetic technique. However, there may be cir-cumstances in which, although the use of a regional technique for apatient with abnormal coagulation may put the patient at significant riskas a result, the alternative for this patient (often a general anaesthetic)may expose them to even greater risk. Experienced clinicians should beinvolved in decisions about whether or not to perform a regional anaes-thetic technique on a patient with abnormal coagulation, and the patientwith capacity should be given all the information he/she needs to makean informed choice.


The Association of Anaesthetists of Great Britain and Ireland.3

W. Harrop-Griffiths et al. | Guidelines: patients with abnormalities of coagulation Anaesthesia 2013

Table

1Recom

mendation

srelatedto

drugsused

tomod

ifycoagulation.

Recom

mendedminim

umtimes

arebasedin

mostcircum

-stanceson

timeto

peak

drug

effect

+(elim

inationhalf-life9

2),afterwhich

time<¼

ofthepeak

drug

levelwill

bepresent.Fo

rthose

drugswho

seaction

sareun

relatedto

plasmalevels,this

calculationis

notrelevant.Dataused

topo

pulate

this

Table

arederivedfrom

ASR

AandESR

Aguidelines

[1,2

]andinform

ationprovided

bydrug

manufacturers.These

recommendation

srelate

prim

arily

toneurax-

ialblocks

andto

patients

withno

rmal

renalfunction

except

where

indicated.

Drug

Tim

eto

peakeffect

Elimination

half-life

Acceptable

timeafter

drugforblock

perform

ance

Administration

ofdrugwhile

spinalorepidural

catheterin

place

1

Acceptable

timeafterblock

perform

ance

orcatheter

removalfor

nextdrugdose

Heparins

UFH

scprophylaxis

<30min

1–2

h4hornorm

alAPTTR

Caution

1h

UFH

ivtreatm

ent

<5min

1–2

h4hornorm

alAPTTR

Caution2

4h

LMW

Hsc

prophylaxis

3–4

h3–7

h12h

Caution3

4h3

LMW

Hsc

treatm

ent

3–4

h3–7

h24h

Notreco

mmended

4h4

Heparinalternative

sDanaparoid

prophylaxis

4–5

h24h

Avo

id(consideranti-Xa

leve

ls)

Notreco

mmended

6h

Danaparoid

treatm

ent

4–5

h24h

Avo

id(consideranti-Xa

leve

ls)

Notreco

mmended

6h

Bivalirudin

5min

25min

10hornorm

alAPTTR

Notreco

mmended

6h

Argatroban

<30min

30–3

5min

4hornorm

alAPTTR

Notreco

mmended

6h

Fondaparinuxprophylaxis5

1–2

h17–2

0h

36–4

2h(consideranti-Xa

leve

ls)

Notreco

mmended

6–1

2h

Fondaparinuxtreatm

ent5

1–2

h17–2

0h

Avo

id(consideranti-Xa

leve

ls)

Notreco

mmended

12h

Antiplateletdrugs

NSA

IDs

1–1

2h

1–1

2h

Noadditionalprecautions

Noadditional

precautions

Noadditional

precautions

Aspirin

12–2

4h

Notreleva

nt;

irreve

rsible

effect


Noadditional

precautions

Noadditional

precautions

Clopidogrel

12–2

4h

7days

Notreco

mmended

6h

Prasugrel

15–3

0min

7days

Notreco

mmended

6h

Ticagrelor

2h

8–1

2h

5days

Notreco

mmended

6h

Tirofiban

<5min

4–8

h6

8h

Notreco

mmended

6h

Eptifibatide

<5min

4–8

h6

8h

Notreco

mmended

6h

Abciximab

<5min

24–4

8h6

48h

Notreco

mmended

6h

Dipyridamole

75min

10h


Noadditional

precautions

6h

Oralantico

agulants

Warfarin

3–5

days

4–5

days

INR≤1.4

Notreco

mmended

Aftercatheter

remova

l

o




Table

1.(Continu

ed)

Drug

Tim

eto

peakeffect

Elimination

half-life

Acceptable

timeafter

drugforblock

perform

ance

Administration

ofdrugwhile

spinalorepidural

catheterin

place

1

Acceptable

timeafterblock

perform

ance

orcatheter

removalfor

nextdrugdose

Rivaroxa

banprophylaxis5

(CrCl>30ml.min

�1)

3h

7–9

h18h

Notreco

mmended

6h

Rivaroxa

bantreatm

ent5

(CrCl>30ml.min

�1)

3h

7–1

1h

48h

Notreco

mmended

6h

Dabigatranprophylaxisortreatm

ent7

(CrCl>80ml.min

�1)

0.5–2

.0h

12–1

7h

48h

Notreco

mmended

6h

(CrCl50–8

0ml.min

�1)

0.5–2

.0h

15h

72h

Notreco

mmended

6h

(CrCl30–5

0ml.min

�1)

0.5–2

.0h

18h

96h

Notreco

mmended

6h

Apixabanprophylaxis

3–4

h12h

24–4

8h

Notreco

mmended

6h

Thrombolyticdrugs

Alteplase,anistreplase,

reteplase,streptokinase

<5min

4–2

4min

10days

Notreco

mmended

10days

UFH

,un

fraction

ated

heparin;

sc,subcutaneous;APTTR,activatedpartialthromboplastintimeratio;

iv,intravenou

s;LM

WH,low

molecular

weightheparin,

NSA

IDs,

non-steroidalanti-inflam

matorydrugs;IN

R,internationalno

rmalised

ratio;

CrC

l,creatinine

clearance.

Notes

toaccompanyTable

11The

dangersassociated

withtheadministrationofanydrug

thataffectscoagulationwhileaspinalor

epiduralcatheterisin

placeshou

ldbe

considered

carefully.T

hereare

limited

dataon

thesafetyof

theuseof

thenewer

drugsin

thisTable,and

they

arethereforeno

trecom

mendedun

tilfurther

databecomeavailable.The

administrationof

thosedrugswho

seentryin

thiscolumnismarkedas

‘caution

’may

beacceptable,but

thedecision

mustb

ebasedon

anevaluation

oftherisksandbenefitsof

administra-

tion

.Ifthese

drugsaregiven,thetimes

identified

inthecolumnto

theleft(‘Acceptabletimeafterdrug

forblockperformance’)shou

ldbe

used

asaguideto

theminim

umtimethatshou

ldbe

allowed

betweendrug

administrationandcatheterremoval.

2Itiscommon

forintravenou

sun

fraction

ated

heparinto

begivenashorttimeafterspinal

blockade

orinsertionof

anepidural

catheter

during

vascular

andcardiac

surgery.

Localclinical

governance

guidelines

shou

ldbe

followed

andahigh

indexof

suspicionshou

ldbe

maintainedifanysignsattributable

tovertebralcanal

haem

atom

adevelop.

3Lo

wmolecular

weightheparins

arecommon

lygivenin

prop

hylactic

dosestwicedaily

aftersurgery,

butmanyclinicians

recommendthat

only

onedo

sebe

given

inthefirst24

hafterneuraxialblockade

hasbeen

performed.

4Con

siderincreasing

to24

hifblockperformance

istraumatic.

5Manufacturerrecommends

cautionwithuseof

neuraxialcatheters.

6Tim

eto

norm

alplatelet

function

rather

than

elim

inationhalf-life.

7Manufacturerrecommends

that

neuraxialcathetersareno

tused.




Table 2 Relative risk related to neuraxial and peripheral nerve blocks inpatients with abnormalities of coagulation.

Block category Examples of blocks in category

Higher risk Epidural with catheterSingle-shot epiduralSpinalParavertebral blocks Paravertebral block

Lumbar plexus blockLumbar sympathectomyDeep cervical plexus block

Deep blocks Coeliac plexus blockStellate ganglion blockProximal sciatic block (Labat, Raj, sub-gluteal)Obturator blockInfraclavicular brachial plexus blockVertical infraclavicular blockSupraclavicular brachial plexus block

Superficialperivascularblocks

Popliteal sciatic blockFemoral nerve blockIntercostal nerve blocksInterscalene brachial plexus blockAxillary brachial plexus block

Fascial blocks Ilio-inguinal blockIlio-hypogastric blockTransversus abdominis plane blockFascia lata block

Superficial blocks Forearm nerve blocksSaphenous nerve block at the kneeNerve blocks at the ankleSuperficial cervical plexus blockWrist blockDigital nerve blockBier’s block

Normal risk Local infiltration

Notes to accompany Table 2There have only been 26 published reports of significant haemorrhagic complications of peripheral nerve andplexus blocks [1]. Half of these occurred in patients being given anticoagulant drugs and half in patients withnormal coagulation. Patient harm has derived from:• Spinal haematoma after accidental entry into the spinal canal during attempted paravertebral blocks asdefined in the Table.

• Exsanguination.

• Compression of other structures, e.g. airway obstruction, occlusion of major blood vessels or tissue ischaemia.

The one death in this series was that of a patient on clopidogrel who underwent a lumbar plexus block andsubsequently exsanguinated. The majority of the 26 cases underwent deep blocks or superficial perivascularblocks. From these data, and from other data relating to neuraxial blocks, we have placed blocks in the order ofrelative risk shown in the Table.Catheter techniques may carry a higher risk than single-shot blocks. The risk at the time of catheter removal

is unlikely to be negligible.Ultrasound-guided regional anaesthesia, when employed by clinicians experienced in its use, may decrease

the incidence of vascular puncture, and may therefore make procedures such as supraclavicular blocks safer inthe presence of altered coagulation.




Table

3Relativerisksrelatedto

neuraxialblocks

inobstetricpatients

withabno

rmalitiesof

coagulation.

Riskfactor

Norm

alrisk

Increasedrisk

Highrisk

Very

highrisk

LMWH

–prophylactic

dose

LMWH

–therapeuticdose

>12h

>24h

6–1

2h

12–2

4h

<6h

6–1

2h

<6h

UFH

–infusion

Stopped>4hand

APTTR≤1.4

APTTRabove

norm

alrange

UFH

–prophylactic

bolusdose

NSA

ID+aspirin

Last

given>4h

WithoutLM

WH

Last

given<4h

WithLM

WH

dose

12–2

4h

WithLM

WH

dose

<12h

Warfarin

INR≤1.4

INR1.4–1

.7INR1.7–2

.0INR>2.0

Generalanaesthesia*

Starved,notin

labour,

antacids

given

Fullstomach

orin

labour

Pre-eclampsia

Platelets

>1009

109.l�1

within

6hofblock

Platelets

75–

1009

109.l�1(stable)

andnorm

al

coagulationtests

Platelets

75–1

009

109.l�1

(decreasing)and

norm

alco

agulation

tests

Platelets

<759

109.l�1

orabnorm

al

coagulationtestswith

indices≥1.5

orHELLP

syndrome

Idiopathic

thrombocytopenia

Platelets

>759

109.l�1

within

24hof

block

Platelets

50–7

59

109.l�1

Platelets

20–5

09

109.l�1

Platelets

<209

109.l�1

Intra-uterinefetaldeath

FBCand

coagulationtests

norm

alwithin

6h

ofblock

Noclinicalproblems

butnoinve

stigation

resultsava

ilable

Withabruptionor

ove

rtsepsis

Cholestasis

INR≤1.4

within

24h

Nootherclinical

problemsbutno

inve

stigationresults

ava

ilable




LMWH,low

molecular

weightheparin;

UFH

,unfractionatedheparin;

APT

TR,activated

partialthromboplastin

time;NSA

ID,n

on-steroidalanti-inflam

matorydrug;INR,

internationaln

ormalised

ratio

.

*Alth

ough

generalanaesthesiaisno

tarisk

factor

perse

forcoagulationcomplications,itisinclud

edin

thisTable

tohighlight

that

thealternatives

toregion

alanaes-

thesia

areno

tfree

ofrisk;thus

arisk–benefitcomparisonisrequ

ired

whenchoosing

oneover

theother.Seeno

tesbelow.

Notes

toaccompanyTable

3Risks:The

risksareprim

arily

thoseof

vertebralcanalhaem

atom

awithsubsequent

cord

compression

andperm

anentdamage.Realisticalternatives

toepidural

analge-

siaexistin

labour,bu

t,forcaesareansection,

thechoice

isthat

ofgeneralor

neuraxialanaesthesia,

andtherisksof

spinal

haem

atom

ain

patients

withabno

rmal

coagulationmustbe

weighed

againstthoseof

generalanaesthesia,

especially

inpatients

who

arein

labour

andhave

afullstom

ach.

These

risksinclud

ehypo

xaem

iaassociated

withdifficulties

maintaining

theairw

ay,pu

lmon

aryaspiration

andthromboem

bolic

complications.

Lowplatelets:The

debateregardingthesafety

ofneuraxialb

lockadein

wom

enwiththrombocytopeniaisguided

byexpertconsensusop

inionin

theabsenceof

clinicaltri-

als;itisno

tthereforepo

ssibleto

give

definitive

values

foralower

limitatwhich

thereisan

increasedrisk

ofhaem

atom

a.Fo

rno

rmalhealthywom

en,there

isno

increased

risk

ofcomplications

withplatelet

coun

ts>1009

109 .l�

1[4].Acoun

tof

>75

910

9 .l�

1hasbeen

prop

osed

asan

adequate

levelfor

region

alblocks

whenthereareno

risk

factorsandthecoun

tisno

tdecreasing

[5].In

pre-eclampsia,a

decreasing

plateletcoun

tisaccompanied

byothercoagulationabno

rmalities,andthisisassumed

tobe

thecase

once

theplateletcoun

tdecreasesto

below1009

109 .l�

1 .Iftheplateletcoun

tisbelowthisvalue,acoagulationscreen

shou

ldbe

performed

–ifthisisno

rmal,it

wou

ldbe

reason

ableto

perform

aregion

alblockdo

wnto

alevelo

f75

910

9 .l�

1 ,depend

ingon

therateof

decrease

inplateletcoun

t[6].In

idiopathicthrombocytopenic

purpuraandgestationalthrom

bocytopenia,thereareredu

cedplateletnu

mbers,but

norm

alfunction

.Inthesesituations,expertop

inionisthatan

experiencedanaesthetist

might

reason

ably

perform

aneuraxialblockade

providingtheplatelet

coun

tis>50

910

9 .l�

1andstable,bu

tan

individu

alrisk–b

enefitassessmentshou

ldbe

made

[7–11].Itispo

ssiblethat

spinal

anaesthesiawithplatelet

coun

tsbelowthislevelmay

besafe

ifdata

areextrapolated

from

that

derivedfrom

lumbarpu

ncturesin

non-

pregnant

patientsperformed

byhaem

atologistsusingneedlesconsiderablylarger

than

thoseused

byobstetricanaesthetists[9].Astablelevelo

f40

910

9 .l�

1may

besafe

forlumbarpu

ncture

intheabsenceof

othercoagulationabno

rmalities.

The

plateletcoun

tshou

ldbe

checkedbefore

anyneuraxialp

rocedu

reifthereisanysuspicionof

decreasing

plateletnu

mbersdu

ring

routineantenataltesting,signs

ofthe

developm

ento

fpre-eclam

psia,e.g.proteinuriaor

hypertension

,orotherclinicalfeatures

suggesting

coagulop

athy,placentalabruptionor

ifthepatient

hasbeen

givenrecent

anticoagulanttherapy.Plateletnu

mbers

candecrease

inpatientstreatedwith

regularheparinfor>4days.O

therwise,itwou

ldno

tbe

routineto

checkplatelet

numbers

anddelayneuraxialb

lock

whilsttheseresults

areaw

aited.

Itwou

ldbe

standard

practiceto

perform

aneuraxialp

rocedu

rewith

in6hof

thelastplateletcoun

tandclottin

gstud

iesin

patientswith

mild

ormod

eratepre-eclampsia.H

owever,ifthepatienthassevere

orfulm

inatingpre-eclampsiaor

HELL

Psynd

rome,aplateletcoun

tandclottin

gstud

iesshou

ldbe

checkedim

mediatelybefore

performingtheprocedure,as

decreasesin

plateletcoun

tcan

occurrapidlyin

thesecircum

stances.

Low

molecular

weightheparins

withaspirin:

Treatmentwithdaily

LMWH

andaspirin75

mgmay

beencoun

teredwhenfollowingNICEguidelines,which

recom-

mendlow-doseaspirinforobesityor

hypertension

.ProvidedtheLM

WH

isstop

pedfor>12

h,theplatelet

coun

tis>75

910

9 .l�

1andno

rmal

coagulationiscon-

firm

ed,neuraxialblocks

canbe

categorisedas

‘increasedrisk’on

ly.

Intra-uterinefetaldeath:

After

intra-uterinedeath,

thereisan

increasedrisk

ofcoagulop

athy

andsepsis,especially

inthesecond

weekafterfetaldemise.Coagulation

abno

rmalitiescanoccuron

presentation

inabou

t3%

ofwom

enwithapparently

uncomplicated

intra-uterinedeath,

andthis

increasesin

thepresence

ofabruption

oruterineperforationto

arou

nd13%

[12].It

isthereforeprud

entto

checkcoagulationstatus

before

anyregion

alprocedure.

The

onsetof

coagulop

athy

isvariable,

butcanbe

rapid.

Cholestasis:In

obstetriccholestasis,coagulop

athy

may

developas

aresultof

decreasedabsorption

ofvitamin

Kessentialforactivation

ofclotting

factors.Itisim

por-

tant

tocheckcoagulationbefore

region

alblockade,bu

tchangesdo

notoccurrapidly.

Rem

oval

ofepidural

catheters:The

recommendation

sgivenin

Table

1fortheremoval

ofepidural

cathetersshou

ldbe

noted.




Table 4 Risks of regional anaesthesia in patients with abnormalities ofcoagulation – special circumstances.

Trauma The coagulopathy of trauma is precipitated by tissue trauma,shock, haemodilution, hypothermia, acidaemia andinflammation. Following major trauma, it is recommended thatan assessment of potential coagulopathy be made beforeperforming any regional anaesthetic technique.

Sepsis Severe sepsis is associated with a procoagulant state. Guidelinessupport the use of chemoprophylaxis against deep venousthrombosis. For advice on regional anaesthesia with intercurrentthromboprophylaxis, refer to Table 1. Septic shock may beassociated with the development of a consumptive coagulopathy.Clinically significant systemic sepsis remains a relativecontraindication to central neuraxial anaesthesia due to thepresumed increased incidence of epidural abscess and meningitis.

Uraemia Uraemia may lead to coagulopathy secondary tothrombocytopenia. It is recommended that all patients withsignificant uraemia undergo assessment of platelet number andfunction before regional anaesthesia. Platelet function may beimproved by the administration of DDAVP.

Patients with chronic renal impairment may be managed withregular dialysis. The presence of residual anticoagulation afterheparin administration must be considered in patients afterdialysis, and heparin reversed if indicated. If regionalanaesthesia is performed, the safety of catheter removal mustbe considered in patients likely to receive heparin duringfurther dialysis.

Liver failure All coagulation factors except factor VIII are synthesised in theliver. Liver failure is associated with haemostatic abnormality,the extent of which must be assessed before regionalanaesthetic techniques are performed. There may bethrombocytopenia and abnormal platelet function due toassociated hypersplenism. Patients in liver failure represent ahigh-risk group for general anaesthesia. When regionalanaesthesia is considered as an alternative, coagulopathy mustbe assessed and corrected when indicated.

Massive transfusion Massive transfusion is associated with altered haemostasis, withdilution and consumption of coagulation factors being theprimary causes in this pathophysiological change. In assessingthe degree of coagulopathy before regional anaesthetic techniques,it is recognised that coagulopathy in massive transfusion is adynamic situation. Assessment should be made when haemorrhageis controlled and the patient is cardiovascularly stable. Anassessment of platelet function should ideally occur in patientswho have been given platelet transfusions.

Disseminatedintravascularcoagulopathy

Disseminated intravascular coagulopathy (DIC) is thepathological activation of coagulation mechanisms in responseto a disease process leading to a consumptive coagulopathy.A diagnosis of DIC is incompatible with safe neuraxialblockade. When peripheral blocks are considered, they shouldbe at compressible sites.

Notes to accompany Table 4All of the conditions discussed can, in their ‘active’ state, be associated with significantcoagulopathy. When regional anaesthesia is thought to be of potential value, e.g. for post-operative analgesia, it should be conducted with reference to the guidelines outlined in therest of this publication.




Advice is often offered that if regional anaesthesia is to be consid-ered in a patient with a known abnormality of coagulation, an ‘experi-enced anaesthetist’ should perform the procedure. There are, of course,no hard data to support this suggestion. However, it is advice that theWorking Party supports. It is likely that an experienced regional anaes-thetist will need fewer attempts to gain block success, and it is likelythat the complications related to bleeding are in part related to thenumber of attempts at a block. It is reasonable to ask novices to per-form their blocks on patients at ‘normal risk’, reserving attempts inpatients at ‘increased risk’ for experienced clinicians.

Guidance is offered here in the form of four Tables, each withexplanatory notes: Table 1 contains recommendations related to drugsused to modify coagulation; Table 2 suggests the relative risk related tothe performance of neuraxial and peripheral nerve blocks in patientswith abnormalities of coagulation; Table 3 indicates relative risks relatedto obstetric patients; and Table 4 describes risks of regional anaesthesiain special circumstances.

Some readers may question the absence of a section on haematologi-cal conditions associated with abnormalities of coagulation – why do wenot mention Christmas disease or other forms of haemophilia? Most ofthese diseases are the result of the absence or shortage in the body of aparticular clotting factor or group of factors. Most of the patients withhaematological diseases such as these reach surgery in the full knowledgethat they have the disease. The standard treatment of bleeding resultingfrom a deficiency of a clotting factor or other contributor to normal coag-ulation when faced with surgery is the administration of that factor orother contributor after guidance from a haematologist. Therefore, for elec-tive surgery, the solution is almost always the performance of the regionaltechnique after acceptable normalisation of coagulation on the advice of ahaematologist. In the emergency situation, urgent advice should be soughtfrom on-call haematologists.

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4. Rolbin SH, Abbott D, Musclow E, Papsin F, Lie LM, Freedman J. Epidural anesthesiain pregnant patients with low platelet counts. Obstetrics and Gynecology 1988; 71:918–20.

5. Douglas MJ. The use of neuraxial anaesthesia in parturients with thrombocytopenia:what is an adequate platelet count? In: Halpern SH, Douglas MJ, eds. Evidence BasedObstetric Anesthesia, 2nd edn. Boston, MA: Blackwell, 2005: 165–77.

6. Sharma SK, Philip J, Whitten CW, Padakandla UB, Landers DF. Assessment ofchanges in coagulation in parturients with preeclampsia using thromboelastogra-phy. Anesthesiology 1999; 90: 385–90.

7. Douglas M, Ballem P. Blood disorders. In: Gambling DR, Douglas MJ, McKay RSF,eds. Obstetric Anaesthesia and Uncommon Disorders, 2nd edn. Cambridge: Cam-bridge University Press, 2008: 303–20.

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10. Van Veen JJ, Nokes T, Makris M. The risk of spinal haematoma following neuraxialanaesthesia or lumbar puncture in thrombocytopenic individuals. British Journal ofHaematology 2010; 148: 15–25.

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12. Maslow AD, Breen TW, Sarna MC, Soni AK, Watkins J, Oriol NE. Prevalence ofcoagulation associated with intrauterine fetal death. Canadian Journal of Anesthe-sia 1996; 43: 1237–43.




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