双语小讲课局麻药中毒

Joseph

M.

Neal,Michael

J.

Barrington,Michael

R.

Fettiplace,MarinaGitman,Stavros

G.

Memtsoudis,EvaE.

Mörwald,Daniel

S.

Rubin,Guy

Weinberg.

The

ThirdAmerican

Society

of

Regional

Anesthesia

and

Pain

Medicine

Practice

Advisory

on

Local

Anesthetic

Systemic

Toxicity:

Executive

Summary

2017[J].

RegionalAnesthesia

and

Pain

Medicine,2018,43(2).There

is

no

single

measure

that

can

prevent

LAST

in

clinicalpractice.Ultrasound

guidance

significantly

reduces

the

risk

of

LAST

inhumans

undergoing

peripheral

nerveblock（外周神经阻滞）.Nevertheless,individual

reports

describe

LAST

despite

the

useof

ultrasound.(I,B)Use

the

lowest

effective

dose

of

local

anesthetic.(I,C)4.Use

incremental

injection（递增式注射）

of

local

anesthetics—administer

3

to

5mL

aliquots（等份）,pausing

15–30

seconds

betweeneach

injection.When

using

a

fixed

needle

approach,eg,landmark,paresthesia-seeking（寻找异感）,or

electrical

stimulation（神经刺激）,timebetween

injections

should

encompass

1

circulation

time

(30–45s).Circulation

time

maybe

increased

with

lower

extremity

blocks（下肢阻滞）or

in

those

patients

with

diminished

cardiac

output.Aspirate

the

needle

before

each

injection,recogniz-

ing

that

there

is

an

2%false

negative

rate（假阴性率）

for

this

diagnostic

intervention.(I,B)When

injecting

potentially

toxic

doses

of

localanesthetic,use

of

an

intravascular

marker

is

recommend-ed.Although

epinephrine（肾上腺素）is

an

imperfect

makerand

its

use

is

open

to

physician

judgment,its

benefits

likelyout

weigh

its

risks

in

most

patients

(IIa,B)Patient

characteristicsExtremes

of

age—less

than

16

or

more

than

60yearsLow

muscle

mass—particularly

with

infants,and

the

debilitatedelderlyFemale

>

maleComorbiditiesCardiac

disease,especially

arrhythmias（心律不齐）,,ischemia（缺血）,and

congestive

heart

failure（充血性心衰）Liver

diseaseMetabolic

disease,especially

diabetes

mellitus（糖尿病）CNS

diseasesLow

plasma

protein

binding（血浆蛋白结合力）—liver

disease,malnourishment（营养不良）,infants,pregnancyLocal

anesthetic

characteristicsBupivacaine

has

a

lower

safety

margin

and

resuscitation

is

moredifficult

in

the

event

of

LAST,but

local

anesthetics

such

as

ropivacaineand

lidocaine

still

account

for

a

significant

proportion

of

LAST

events.Block

site,total

local

anesthetic

dose,test

dosing,and

patientcomorbidities

are

more

predictive

of

high

plasma

levels（血浆浓度）of

local

anesthetic

than

are

body

weight

or

body

mass

index.Seizure

is

up

to

5

times

more

likely

after

PNB

than

epidural

block（硬膜外阻滞）.Classic

descriptions

of

LAST

depict

a

progression

of

subjectivesymptoms

of

CNS

excitement(agitation（烦躁）,auditory

changes（听觉改变）,metallic

taste（金属感味觉）,followed

by

seizures

then

CNSdepression(coma,or

respiratory

arrest).Near

the

end

of

this

continuum,

initial

signs

of

cardiac

toxicity(hypertension,tachycardia（心动过速）,orventriculararrhythmias（室性心律失常）)are

supplanted

by

cardiac

depression

(bradycardia,conduction

block,and

hypotension).If

signs

and

symptoms

of

LAST

occur,promptand

effective

airway

management

is

crucial

topreventing

hypoxia,hypercapnia（高碳酸血症）,andacidosis（酸中毒）,which

are

known

to

potentiateLAST.(I;B)Lipid

emulsion

therapy(I;B): Administer

at

the

first

signs

of

LAST,after

airway

management2.Timeliness

of

lipid

emulsion

is

more

important

than

the

order

ofadministration

modality（给药方式）(bolus

vs

infusion)20%

lipid

emulsion

BOLUS100mL

over

2–3

min

if

patient

is

over

70kg1.5mL/kg

over

2–3

min

if

patient

is

less

than

70kg20%

lipid

emulsion

INFUSION200–250mL

over

15–20

min

if

patient

is

over

70kg0.25mL/kg/min

if

patient

is

less

than

70kg

(ideal

body

weight)If

circulatory

stability

is

not

attained,consider

rebolus

or

increasinginfusion

to

0.5mL/kg/minContinue

infusion

for

at

least

10min

after

circulatory

stability

is

attained.Approximately

12mL/kg

lipid

emulsion

is

recommended

as

the

upperlimit

for

initial

dosing.(IIb;B)Propofol

is

not

a

substitute

for

lipid

emulsion.(III;B)Seizure

control:If

seizures

occur,they

should

be

rapidly

halted

withbenzodiazepines（苯二氮卓类）.If

benzodiazepines

are

not

readilyavailable,lipid

emulsion

or

small

doses

of

propofol

areacceptable.(I;B)Although

propofol

can

stop

seizures,large

doses

further

depresscardiac

function;propofol

should

be

avoided

when

there

are

signs

ofcardiovascular

compromise.(III;B)2.If

seizures

persist

despite

benzodiazepines,

small

doses

ofsuccinylcholine（琥珀胆碱）

or

similar

neuromuscular

blocker

shouldbe

considered

to

minimize

acidosis

and

hypoxemia.(I;C)If

cardiac

arrest

occurs:If

epinephrine

is

used,small

initial

doses(≤1μg/kg)

arepreferred.(IIa;B)Avoid

calcium

channel

blockers（钙通道阻滞剂）

and

β-adrenergic

receptor

blockers（