MINERVA MEDICA COPYRIGHT ® SIAARTI guidelines for safety in locoregional anaesthesia

34 Pages·2006·0.17 MB·English

LINEE GUIDA SIAARTI
MINERVA ANESTESIOL 2006;72:689-722
A
SIAARTI gCuidelines
for safety in locoregional anaesthesia
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L. BERTINI 1, G. SAVOIA 2, A. DE NICOLA 3, G. IVANI 4, E. GRAVINO 5, A. ALBANI 6, F. ALEMANNO 7
A. BARBATI 8, B. BORGHI 9, F. BORROMETI 10, A. CASATI 11, D. CELLENO 12, A. CIASCHI 1
E
A. CORCIONE 13, P. DE NEGRI 14, P. DI BENEDETTO 15, M. EVANGELISTA 16, G. FANELLI 11, P. GROSSI17
M. LORETO 8, E. MARGARIA 18, P. MASTRONARDI 5, C. MATTIA 19, F. NICOSIA 20, M. NOLLI 21
A. RUTILI 22, E. SANTANGELO 23, J. SUCRE 3, V. TAGARIELLO 24, G. VARRASSI 25, F. PAOLETTI 26
M
R. TUFANO 5
®
1Anaesthesiology in Trauma Surgery 13Monaldi Hospital
and Pain Therapy Un it T Naples, Italy
CTO Hospital, ASL RMC, Rome,A Italy 14Service of Anaesthesiology
2Service of Anaesthesiology Intensive Care and Pain Therapy, IRCCS Hospital
and Paediatric Intensive Care H Rionero in Vulture, Potenza, Italy
A. Cardarelli Hospital, VNaples, Italy 15Service of Anaesthesiology and Intensive Care
3Service of Anaesthesiology and Intensive Care S.Andrea University Hospital
ASL Na5, Castellammare di Stabia Rome, Italy
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Naples, Italy 16Service of Anaesthesiology and Intensive Care
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4Service of Anaesthesiology and Intensive Care A. Gemelli Hospital, Cattolica University
Regina Margherita Children’s Hospital Rome, Italy
Turin, ItalIy 17Service of Locoregional Anaesthesiology
5Department of SuErgery, Anaesthesiology and S. Donato Hospital
Intensive Care, Federico II UnivRersity Milan, Italy
Naples, Italy 18SIAARTI Representative
6AnaesNthesiology, Intensive Care and Pain of the Piedmont Region, Italy
Therapy Unit, Valle d’Aosta RegioYnal Hospital, 19Department of Anaesthesiology
Aosta, Italy La Sapienza University
7Department of Anaesthesiology and Pain Rome, Italy
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Therapy, Moro-Girelli Hospital 20Service of Anaesthesiology and Intensive Care
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M Don Carlo Gnocchi Foundation Gallieri Hospital
Brescia, Italy Genoa, Italy
8Anaesthesiology and Intensive Care Unit 21Anaesthesiology
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ASL Sa1, Salerno, Italy Pain Therapy and Perioperative Unit
9Service of Anaesthesiology and Intensive Care Cremona Hospital
Istituti Ortopedici Rizzoli Cremona, Italy
C Bologna, Italy 22Service of Anaesthesiology and Intensive Care
10Service of Anaesthesiology and Intensive Care, S. Giacomo e Cristoforo Hospital
Santobono Hospital ASL 1, Massa, Italy
Naples, Italy 23Department of Anaesthesiology and Intensive
11Department of Anaesthesiology, Parma Care, Magna Grecia University
University, Parma, Italy Catanzaro, Italy
12Service of Anaesthesiology and Intensive Care, 24Service of Anaesthesiology
Fatebenefratelli Hospital, Isola Tiberina Intensive Care and Pain Therapy
Rome, Italy Fatebenefratelli Hospital, Villa S. Pietro
Rome, Italy
25Service of Anaesthesiology and Intensive Care
Address reprint requests to: R. Tufano, Dipartimento di L’Aquila University, L’Aquila, Italy
Scienze Chirurgiche, Anestesiologiche e Rianimatorie, 26Service of Anaesthesiology and Intensive Care,
Università degli Studi Federico II, Via Pansini 5, 80131 Napoli. Perugia Hospital, Perugia, Italy
E-mail: [email protected]
Vol. 72, N. 9 MINERVA ANESTESIOLOGICA 689
BERTINI SIAARTIGUIDELINESFORSAFETYINLOCOREGIONALANAESTHESIA
The aim of this document is to offer to the evidence medicine are the most relevant fac-
Italian anaesthetists a number of indica- tors in the process of improving and main-
tions, based on the scientific evidence, on taining high therapeutic standards, particular-
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the effective and safe practice of local-region- ly in the field of anaesthesia, where different
al anaesthetic techniques. possibilities of treatment may exist. The best
In this document, the working group utilised practice for each patient will vary according
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the standard graduation scale of the evidence his specific necessities, and the use of any
ad derived from the existing scientific literature: regional anaesthesia technique, as a part of a
grade 1, evidence from meta-analyses of all treatment scheme, wIill require an adequate
controlled and randomised trials, grade 2, evi- preparation of the patient as well as an evalu-
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dence from controlled and randomised trials, ation of the potential risks and benefits.
grade 3, evidence from observational studies
and nonrandomised trials. Where scientific PreparatioEn of the patient
evidence is not demonstrable, expert judg-
The regional anaesthesia is not necessari-
ments are referred (grade 4).
The guidelines are not protocols, which ly aM better alternative to the general anaes-
thesia; if the patients fully satisfies the nec-
suppose a rigid, invariable application; they
essary conditions, both® anaesthesias shall be
are recommendations intended to improve
considered applicable to a given patient. The
the quality, the effectiveness and the safety o f T
preoperative preparation for a regional anaes-
the local-regional anaesthesia amongA the
thesia should follow the same therapeutic
members of the Society. These guidelines are
standards Hof the general anaesthesia. Some
strong enough to influence the standards of
V situations may require a particular manage-
the clinical practice, but the same time they
ment and the formulation of specific guide-
allow a sufficient flexibility to be introduced
lineGs within the operating unit.
in the clinical practice of the different pro-
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fessional spheres of the individual members. — Guidelines for the preoperative fasting:
The guidelines should encourage the devel- - the regional anaesthesia may be effec-
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opment of local guiEdelines to suit the partic- tive not in all cases, and it may be necessary
ular requirements of each hospital, oRf the to resort to the general anaesthesia;
members of operative units of anaesthesia - adverse reactions to the used region-
as a function Nof the type of organisation and al anaesthesia technique may require resus-
of the patients to be handled. TYhe regional citation manoeuvres; in such case, it is prefer-
anaesthesia cannot be interpreted as an exact able to have an empty stomach.
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science and it is not possible to establish rigid Therefore, with exception of minor (more
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proM tocols covering every detail of a regional peripheral) blocks, it should be better to have
anaesthetic technique. Guidelines in the clin- the patient fasting as in the case of a gener-
ical use are more pOractical and useful than al anaesthesia.
protocols for the improvement of standards, — All preoperative medicaments shall be
as they leave the clinical liberty of selecting specified.
the most aCppropriate treatment for each — Patients and nurses shall be informed on
patient. the medicaments which may be preopera-
tively administered.
— The preoperative treatment of pre-exist-
Preparation of the patient and ing pathological situations should be con-
informed consent sidered as for a general anaesthesia.
— Every effort should be made to improve
In our days, patients are more conscious of the general preoperative condition of the
their own clinical situation and show an patient, and, where possible, the pathologi-
increasing desire to be involved in the decisions cal conditions should be corrected.
regarding the treatment scheme. The clinical — Particular care shall be exerted when
risk management and the decision based on the using regional anaesthesia in patients at risk.
690 MINERVA ANESTESIOLOGICA Settembre 2006
SIAARTIGUIDELINESFORSAFETYINLOCOREGIONALANAESTHESIA BERTINI
It is important to optimise, in addition to The explanation
the physical, also the psychological condi-
The explanation given to the patient shall
tions, in order that the patient may fully
include a summary of what he wAill undergo,
understand the information given to him and
feel and see during:
give a really conscious consent.
— the implementation of the block;
Besides, many patients have some preju-
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— the surgical operation;
dices about peripheral blocks, which make
— the recovery from the block.
them anxious:
— fear of the unknown; The explanatioIn should include general
information about the benefits of the pro-
— precedent negative surgical experiences; D
posed block and the possible risks connect-
— incorrect information from relatives,
ed with it. Some information are of a gener-
friends, other patients, surgeons, nurses.
al character and are applicable to all tech-
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These anxieties should be soothed through
niques of regional anaesthesia, whereas oth-
an adequate preoperative talk with the anaes-
er information will be specific of the pro-
thetist. pMosed technique. The choice, whether to use
the regional anaesthesia alone or in con-
Informed consent junction with a ligh®t general anaesthesia or
The informed consent involves a wri tten with an intraveTnous sedation shall be appro-
priate to the surgical and anaesthesiological
contract between the physician who wAill car-
requirements, as well as to the personal pref-
ry out the procedure and the patient who
erences Hof the patient.
will undergo the proposed treatment or pro-
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cedure. This presupposes some commitments
bay both parties. Risk evaluation
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“... the obligation to exRplain to the patient Any risk connected with the proposed
risks and benefits of a given anaesthesia
technique shall be discussed with the patient
scheme with respect to another scheme.I.. and shall be exposed in a clear and scientif-
... obviously, thEe anaesthetist should him- ically valid language, considering the sever-
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self be personally convinced that the rec- ity of the correlated risks and their statistical
ommendedN technique is the best choice, oth- incidence. For instance:
erwise it will be difficult to give to the patient
Y — postspinal cephalea: <1:100;
the necessary assurances.”
— paralysis or death: 1: 100-110 000;
The anaesthetist:
I — failure of the block: up to 10-15%;
M — shall give the explPanations with a sim- — temporary paraesthesia: variable and
ple language; difficult to be quantified;
— should giveO information with sincerity — permanent lesion of the nerves:
and confidence; 1:10.000.
— should persuade, but not insist on the
It is necessary to balance the risks of the
preferred technique, if not essential;
C regional anaesthesia connected with the pos-
— should give the patient the time to put
sible lesion of the nerves, against the risks
questions;
of hypoxic cerebral damage and death caused
— should enter a written note on the case
by the general anaesthesia, which the patient
file.
may consider as nonexisting.
The patient:
— shall be in such a condition as to under-
stand and cooperate; Instrumental requirements for major
— should be able to put questions and to regional blocks
express his anxieties and fears;
— may not desire to know all details, and The instrumental requirements for each
prefer to rely on the physician. peripheral block may vary according to the
Vol. 72, N. 9 MINERVA ANESTESIOLOGICA 691
BERTINI SIAARTIGUIDELINESFORSAFETYINLOCOREGIONALANAESTHESIA
used technique, but there are some basic In case of patients undergoing a central
requirements which are essentials wherever block, particularly if elderly, it would be
the anaesthesia is practiced: advisable to administer oxygen with the mask
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— sure access to the vein; throughout the operation, with appropriate
— intensive care equipment and medica- concentrations.
ments at immediate disposal and capacity of The prime responsibilCity of the anaesthetist
using them. In particular, it is advisable to is to the patient who is the object of his care.
have directly available such medicaments as The anaesthetist shall remain with the patient
atropine and ephedrine, for the immediate throughout the coInduct of the anaesthesia, of
treatment of the first symptoms of hemody- major blocks and of deep sedations. The
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namic instability; anaesthetist should leave the patient only
— adequate monitoring; when the latter has been transferred to the
— immediate availability of the necessary care oEf the recovery room or to the appro-
equipment for a general anaesthesia; priate ward. In particular circumstances, such
— a sterile area of adequate width, to car- as to give aid to a colleague in difficulty or to
ry out the block; Massist another patient in danger of life, the
— all sterility precautions for major blocks; anaesthetist may delegate to another profes-
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— surgical washing of the hand, then ster- sional figure the monitoring only of the
ile hut, mask, gloves and coat if neces sary; patient. In suTch situations the anaesthetist
— sterile cloths around the injectAion site; should inform the surgeon.
— availability of other sterile material; Contemporary performing of general,
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— needles, syringes and catheters. spinal, epidural anaesthesias or other major
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blocks by only one anaesthetist is not accept-
The environment of the patient while the
able for both therapeutic and diagnostic pro-
anaesthetical procedure is carried out should G
cedures. However, in an unit of obstetrics, it
be agreeable; it should Rprovide an adequate
is possible that only one anaesthetist super-
privacy and be heated and comfortable.
vises more than one patient under analgesia
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E for labour. Adequately trained persons shall
R be present to carefully control each patient.
Perioperative conduct
When an anaesthetist is providing analgesia
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When the block is stabilised, a test shall for a delivery, a second person adequately
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be made of the depth of the motive and sen- trained shall be present and prepared to per-
sitive block of the area which is to be affect- form intensive care to the newborn baby.
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ed by the surgical act, as well as of the entire Contemporary administration of an anaes-
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Mextension of the block before the surgical thesia and performing of more than one diag-
action begins. During the operation it is nostic or therapeutic procedure by a single
important to maOke sure that: physician is not acceptable, with exception of
— the comfort and the psychological well- procedures involving an anaesthesia by infil-
being of the patient are not jeopardised; tration of local anaesthetic.
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— the discomfort connected to the envi-
ronment is minimal;
— the noise is reduced as far as possible to Postoperative treatment
create a relaxing environment;
— the position of the patient is correct; The anaesthetist who has performed the
— protections are provided both for the block remains responsible of the effects of the
anaesthetised and nonanaesthetised areas; block till its complete regression, unless the
— stimulations outside the anaesthetised responsibility is formally transferred to a col-
area are prevented. league or to another member of the staff.
In addition, the patient should be given The patients and his relatives shall be reas-
the choice between being or not being sedat- sured and be given information about:
ed. — the anticipated duration of the block;
692 MINERVA ANESTESIOLOGICA Settembre 2006
SIAARTIGUIDELINESFORSAFETYINLOCOREGIONALANAESTHESIA BERTINI
— the manner of recovery of the function; the different regimes of antiembolic throm-
— how to maintain the anaesthetised area; boprophylaxis in use.
— possible motive, sensitive and proper-
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ceptive alterations;
— mobilisation; Incidence of the hemorrhagic risk
— particular information shall be given to during an anticoagulant and
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the relatives: antithrombotic therapy
- in a day-surgery regime;
Bleeding constitutes the most severe com-
- with continuous blocks. I
plication during an anticoagulant and
antithromDbotic therapy. The hemorrhage is
classified as major if it takes place in intracra-
Documentation
nial, intraspinal, intraocular, mediastinal and
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retroperitoneal locations, if it brings the patient
It is essential that the case file contains all
to death or causes the patient to be hospi-
data relative to the performance of the region-
M talised or to undergo a transfusion therapy.
al block. Also, written guidelines should be
The risk factors of major hemorrhages during
available, giving information and advice on
an anticoagulan®t therapy include the intensi-
all peculiar aspects of every operative unit.
ty of the anticoagulant effect itself, the
Guidelines should be available for: T
advanced age, the feminine sex, a positive
— Patients and relatives A anamnesis for gastro-intestinal hemorrhages,
- preoperative information on anaes- a coHncomitant use of aspirin and the duration
thesia and surgery; V of the therapy.1, 2 During treatment with
- at the discharge other prescription shall dicumarolics, an INR value between 2 and 3
be given for the pain, the care of the affectG- is associated with a low bleeding risk: <3% in
ed area ad the mobRilisation; a three-month therapy. More intense treat-
- how to contact the hospital in case of ments with an INR value >4 are associated
other necessities. I with a higher hemorrhagic risk (7%). The inci-
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— Paramedical attendants dence of hemorrhagic complications with intra-
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- prescriptions for the care of the patient; venous sodium or calcium heparin and with a
- Nprescriptions for the treatment of the LMWH is lower than 3%.1 During a throm-
pain; Y bolitic therapy the hemorrhagic risk, which is
- how to contact the medical staff in comprised between 6% and 30%,3 is higher
Icase of necessity. in patients which undergo a treatment for
P deep venous thrombosis. However, although
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the thromboembolism remains a severe risk
Anticoagulants factor for morbidity and mortality, its preven-
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and local-regional anaesthesia tion and treatment are not themselves without
risk.
Many millions of central blocks are per-
formCed in Europe, mostly on hospitalised
patients who receive an antiembolic throm-
Incidence and risk factors of clinically
boprophylaxis, usually with unfractionated
relevant spinal bleedings
heparin (calciparin/hepatin), or with low
molecular weight (LMWH). Reported cases of The spinal haematoma, defined as a symp-
accidents which produce bleeding with per- tomatic bleeding internal to the neuraxis, is a
manent neurological damage are extremely rare and potentially catastrophic complication
scarce; however, to reduce the risk, SIAARTI of the central anaesthetic block. The actual
has developed these guidelines on the hemo- incidence of such a complication is unknown.
stasis for central block, in association with From the available literature,4 the probable
anticoagulants. These guidelines may be dif- incidence of major bleedings after perform-
ferent from the non European guidelines for ing a central block without specific risk factors
Vol. 72, N. 9 MINERVA ANESTESIOLOGICA 693
BERTINI SIAARTIGUIDELINESFORSAFETYINLOCOREGIONALANAESTHESIA
TABLEI.—Risk factors. and clopidogrel) and the antagonists of the
GP IIb/IIIa receptives (abciximad, eptitiphy-
Risk factors relative Risk factors relative
to the patient to the anaesthetic tecnique batide and tyrifibran); such medicaments
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have different pharmacological properties
Spinal anomalies Technical problems
and different effects on the platelets.
Age higher than 70 years Repeated punctures
The cyclo-oxygenases exist in 2 forms: the
Female gender Traumatic punctures C
Anticoagulants Catheters (epidural) COX-1 control the constitutive mechanisms,
Positive anamnesis Removal of the catheter whereas the COX-2 moderate pain and
for coagulopathies
inflammation. TheI NSAIDS inhibit the platelet
cyclo-oxygenases and prevent the synthesis
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of A thromboxane; the platelets of the sub-
2
has been approximately calculated as less than ject who assume these substances have a
1:220,000 for the spinal anaesthesia and less normaEl adhesion to the subendothelium and
than 1:150,000 for the epidural anaesthesia.4 a normal formation of the primary thrombus.
The highest bleeding risk is connected to posi- With a dose-dependent effect, aspirin and
tioning and removing an epidural catheter, Mother NSAIDS may produce different effects
the lowest to the single-shoot spinal, while on coagulation. For instance, the platelet
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another variable is connected to the calibre cyclo-oxygenases are inhibited by low doses
of the needle used.5, 6 About 60-80% o f all of aspirin (60-T325 mg/die), while higher dos-
major bleedings is associated to haemAostatic es (1.5-2 g/die) inhibit also the production
disorders or bleedings from the needle.7 The of prostacyclines by the endothelial cells.
neurological damage appears as a progres- The bHleeding time is considered as the best
sion of sensitive or motive blockV (68%) or with control method of the pharmacological activ-
malfunctions of the alvus or of the bladder, ity of these substances. However, no clinical
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often without intense lumbar pain. Although evidence indicates that the bleeding time may
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only 38% of the patients obtain a partial or actually show that the haemostasis is com-
total neurological recovery, medullary ischemia promised.8The platelet functionality is com-
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tends to be reverEsible if the patient undergoes promised throughout the life of a platelet by
a decompressive laminectomy within R8 h from the taking of aspirin, while other NSAIDS
the appearance of the neurological signs.7For produce a shorter alteration which disap-
this reasonN, it is important to keep a constant pears within 3 days.9
neurological monitoring in theY patients at risk. The new selective inhibitors of the COX-2
Although the insertion of a spinal or act on an enzyme which is non present on
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epidural catheter may produce significant the platelets and, therefore, have no effects on
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Mbleeding, also the removal of a catheter shall their functionality.10As a matter of fact, both
be considered as a risk factor for an impor- after a single dose and after prolonged admin-
tant spinal bleedOing; 30-60% of the clinically istering, no significant alteration of the platelet
important haematomas have been observed aggregation has been noticed and, conse-
after the removal of a catheter. quently, no significant bleeding has been
The foCllowing clinically important risk fac- reported. The contemporary use of inhibitors
tors for bleedings have been identified and a COX-2 and dicumarolics may increase the
careful examination and evaluation of the hemorrhagic risk by increasing the PT.
abnormalities of the coagulation is essential The antiplatelet effect of the derivatives of
before any central block (Table I). the tieroperidine, ticlopidine and clopido-
grel, is produced by the inhibition of the
platelet aggregation induced by the adenosis-
Antiplatelet agents diphosphate. Ticlopidine and clopidogrel
interfere also with the fibrinogen-platelet
Pharmacology of the antiplatelets
bond and with the consequent interaction
The antiplatelet agents include the NSAIDS, between platelets.11 The derivative of the
the derivatives of the tienopiridine (ticlopidine tieroperidine show also a dose- and time-
694 MINERVA ANESTESIOLOGICA Settembre 2006
SIAARTIGUIDELINESFORSAFETYINLOCOREGIONALANAESTHESIA BERTINI
dependent effect; the steady state is reached tor (surgical bleeding) in neurosurgery and
in 7 days for clopidogel and in 14-21 day for plastic surgery. Certainly, the concomitant
ticlopidine. Although these medicaments are administration of other medicaments which
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often administered in association with aspirin, have the possibility of altering the coagulation
the safety of this contemporary use has not mechanisms (e.g. heparin, oral anticoagu-
been established and might be associated lants, dextranes) may significantly increase
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with an increase of the risk of bleeding. In the the risk of complications from bleeding and
course of a therapy with these medicaments, shall be considered in the decision to per-
there has been described the appearance of form a central bIlock. Where there exists the
adverse haematological events such as agran- alternative of a regional block for a given
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ulocitosis, thrombotic thrombocytopenic pur- surgical procedure, it is logical to use the
ple and aplastic anaemia. State recommen- technique with has the lowest risk of spinal
dations prescribe to interrupt the adminis- bleedEing (e.g. spinal with thin needle).
tration of clopidogrel 7 days and of ticlopidine
10-14 days before the operation.
Incidence of epidural haematomas during a
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The antagonists of the GP IIb/IIIa platelet
therapy with antiplatelets
receptors, which include abciximab, eptiphi-
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batide and tyrofibran, inhibit the platelet At the First American Society of Regional
aggregation by interfering with the fibrin ogen- Anesthesia T(ASRA) Consensus Conference
platelet and platelet-factor of von WAillebrand on Anti-coagulation and Central Blocks it did
bonds. Since the fibrinogen and the factor not appear that there existed a significant
of von Willebrand have several bond sites, incremHent of the bleeding risk for the patients
they may bind themselvVes with many undergoing antiplatelet therapy.12 Successi-
platelets, producing a cross-bond and con- vely, Vandermeulen et al.7reported 3 cases of
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sequently the platelet aggregation. On the spinal haematoma in their review of 61 cas-
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contrary, the inhibition of the GP IIb/IIIa es, and 4 additional cases were reported at a
blocks the final common way of the platelet later date.13-17 Data are undoubtedly scarce,
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aggregation. ThEe majority of the clinical trials considering also the great number of patients
which involved the GP IIb/IIIa werRe effected who take NSAIDS because of acute or chron-
on patients with contemporary administra- ic pain and eventually undergo invasive pro-
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tion of aspirin and heparin. The contraindi- cedures.
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cations include a positive anamnesis for sur- Numerous studies on a high number of
gical operations in the 4-6 preceding weeks. patients have shown the relative safety of
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The time required to bring the platelet aggre- performing central blocks during an
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M gation back to its normal conditions, after antiplatelet therapy, but the total number of
interrupting the administration of the medica- enrolled patients was only 4714.12 To this
ment, goes froOm 8 h for eptiphibatide to 24- group is to be added the obstetrical popula-
48 h for abciximab. In the course of a thera- tion of 1422 patients at high risk under ther-
py with GP IIb/IIIa antagonists, it is strong- apy with 60 mg of aspirin, who underwent an
ly recoCmmended to avoid puncturing non- epidural anaesthesia without any neurologi-
compressible vessels and central blocks. cal consequence 18 and 1214 patients who
Very rare cases of spinal bleeding associ- were treated with epidural steroids.19Aspirin
ated with antiplatelet therapy have been should not withdraw in patient to be sub-
reported, although these agents are com- mitted to noncardiac surgery until other
monly associated with central blocks. thromboprophylactic drugs start.5, 20, 21
Therefore, it can be said that, with the usual No controlled study have been carried out
doses, the antiplatelets (aspirin and/or during a therapy with derivatives of tienoperi-
NSAIDS) do not increase significantly the risk dine and antagonists of GP IIb/IIIa. Though
of bleeding after a central block, if other risk with a very limited number of available cas-
factors can be excluded. The antiplatelets es, it seems that a higher intraoperative bleed-
have been identified as a significant risk fac- ing was noted with these medicaments.22-24
Vol. 72, N. 9 MINERVA ANESTESIOLOGICA 695
BERTINI SIAARTIGUIDELINESFORSAFETYINLOCOREGIONALANAESTHESIA
Three spinal haematomas during a therapy ticlopidine, clopidogrel and antagonists of
with ticlopidine or clopidogrel have been the platelet receptors GP IIb/IIIa is not
described, including a patient undergoing an known. From the existing data the suggested
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epidural therapy with steroids 15, 17, 24 time interval for the safe interruption of the
Moreover, 2 cases have been reported of ticlopidine is 14 days and for the clopidogrel
severe hemorrhages after a block of the lum- 7 days.1
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bar sympathetic in patients undergoing a The antagonists of the platelet receptors
therapy with ticlopidine and clopidogrel;25 IIb/IIIa exert a deep effect on the platelet
all this should be a warning about the poten- aggregation, which dIisappears after 4-48 h
tial bleeding risk for these patients. from the interruption of the therapy.
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The administration of NSAIDS alone does Obviously, the central block is contraindi-
not increase the bleeding risk, but it has been cated till the resumption of the normal platelet
shown that the association with other medica- activity. AccEording to the technical cards, the
ments which interferes at various levels with surgical act is not advisable for at least 4
the coagulation mechanisms increases the weeks from the interruption of the therapy.
frequency of spontaneous hemorrhagic com- TheM concomitant use of more medicaments
plications, bleeding at the injection sites and which interfere with coagulation increases
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spinal haematomas.3, 5, 26For instance, in the the bleeding risk. The COX-2 inhibitors have
series of 40 spinal haematomas associated a minimum interfTerence with the platelet
with LMWH therapy, 10 patients had receivAed activity and should be considered for those
a concomitant treatment with antithrombot- patients who require a treatment with anti-
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ic medicaments, and also in the series inflammatories.1, 10
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described by Benzon et al. all patients had
received a contemporary administration of
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antiplatelet medicaments.15 R Oral anticoagulants
The therapeutic anticoagulation with oral
Anaesthesiological management of patientsI
E dicumarolic anticoagulants should be con-
undergoing an antiplatelet therapy
R sidered as an absolute contraindication for a
The pharmacological differences which central block. For patients undergoing a
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exist among the various medicaments make chronic therapy with oral dicumarolic anti-
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it difficult to give different indications for coagulants, this therapy should be interrupt-
each of them. ed at least 4 to 5 days before the operation
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There does not exist any universally accept- and the PT/INR should also be checked
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ed teMst, inclusive of the bleeding time, which before the intervention. It is to be remem-
may give a guidance in the platelet treatment. bered that shortly after the interruption of
It is very important tOo perform an accurate the dicumarolics, the PT/INR reflects above
preparatory examination of the patients to all the plasmatic levels of VII factors, and
the aim of individuating associate patholo- although these values are acceptable, the lev-
gies which mCay further interfere with the els of factors II and X may be inadequate for
coagulation, keeping in mind the conditions a normal haemostasis.
which by themselves do increase the bleed- Presently, in Europe, the oral anticoagu-
ing risk. lants are not widely used to prevent throm-
The NSAIDS alone seem not to increase boembolic complications. There are not suf-
the bleeding risk. ficient data in the literature to determine the
Presently there do not exist specific rec- real risk connected to the performance of
ommendations regarding the time interval single or continuous central blocks in patients
between administration of the NSAIDS and undergoing a prophylactic therapy with
performance of the technique or removal of dicumarolics. There exist 2 cases in the liter-
the epidural catheter. ature, which describe the appearance of a
The real risk connected to the therapy with spinal haematoma in patients undergoing a
696 MINERVA ANESTESIOLOGICA Settembre 2006
SIAARTIGUIDELINESFORSAFETYINLOCOREGIONALANAESTHESIA BERTINI
TABLEII.—Risk factors and estimated incidence of spinal hematoma during central block.
Relative risk Estimated risk Estimated risk
haematoma haematoma for spinal
A
Without heparin therapy
Atraumatic puncture 1 1:220,000 1:320,000
Traumatic puncture 11.2 1:20,000 C 1:29,000
With aspirine 2.54 1:150,000 1:220,000
Administration of unfractionated heparin after spinal procedures
I
Atraumatic 3.16 1:70,000 1:100,000
Traumatic 112 D1:2,000 1:2,900
Administration of heparin >1 h after the puncture 2.18 1:100,000 1:150,000
Administration of heparin <1 h after the puncture 25.2 1:8,700 1:13,000
With aspirin 26 1:8,500 1:12,000
E
Modified from Stafford-Smith.6
M
thromboprophylactic therapy with continuous or epidural anaesthesia may be associated with
®
epidural analgesia.27 an increase of the risk that a spinal hematoma
In patients who receive low doses o f appears. The dataT from the literature 28derive
dicumarolics before a surgical operation Aand mostly from a study effected on 342 patients
at the same time undergo a continuous epidur- who had received therapeutic doses of heparin
H
al analgesia, the PT/INR should be evaluates through lumbar puncture to treat an acute cere-
V
and checked before the removal, if the anti- bral ischemia. Seven of these patients devel-
coagulant therapy has been initiated more oped a spinal hematoma. Three risk factors
G
than 36 h before. In patienRts with epidural have been identified: an interval shorter than
catheters having an INR >3, the dicumarolic 60 min between the administration of heparin
therapy should be interrupted and the removal and the spinal puncture, a traumatic perfor-
I
postponed. There areE no data in the literature mance of the technique and the concomitant
to define with certainty when epidRural use of other anticoagulants (aspirin). These
catheters may be removed in patients with risk factors have been checked in other reviews
N
therapeutic levels of dicumarolics. On the basis of case reports of haematomas associated with
Y
of the pharmacologic knowledge, the catheters spinal techniques during a therapy with non-
should be removed with values of INR <1.5. A fractionated heparin 6, 7, 29(Table II).6
I
clinical appraisal shall be exerted to decide
P
whMether to remove or to maintain in place
Interoperative systemic heparinisation
these catheters. Accurate neurological evalu-
ations shall be madOe as a routine on these Particularly in the vascular surgery it is fre-
patients. The analgesic solution should indicate quent to use 5,000 or 10,000 U of intravenous
the use of low doses and concentrations of unfractioned heparin in order to prevent
local anaesthCetic in order to simplify the mon- coagulative phenomena during the block of
itoring of the motive function. the local arterial circulation.30With this kind
of surgery, however, it has been established
that the epidural analgesia has a validity in
Unfractionated heparin decreasing morbidity and improving the con-
trol of the postoperative pain,31 and in such
Risk factors for the appearance of spinal
patients the risk of epidural hematoma may
haematoma in patients treated with unfrac-
be enhanced.7, 29
tionated heparin and subjected to a central
Most of the data in the literature refer to sim-
block
ilar guidelines, which include the performance
The contemporary administration of unfrac- of the procedure at least 1 h before the admin-
tionated heparin and performance of a spinal istration of heparin 32 and the exclusion of
Vol. 72, N. 9 MINERVA ANESTESIOLOGICA 697
BERTINI SIAARTIGUIDELINESFORSAFETYINLOCOREGIONALANAESTHESIA
patient at high risk with pre-existent coagu- — there shall be an interval of 60 min
lopathies. There are still controversies about the between central block and administration of
action in case of traumatic puncture (bleed- heparin;
A
ing while the catheter is positioned). Precedent — the heparinic effect shall be controlled
surveys reported an incidence of 50% of frequently with the aim of administering the
haematomas in case of traumatic puncture fol- minimum doses compatible with the thera-
C
lowed by a therapy with unfractioned heparin.7 peutic objective;
For this reason, it was suggested to postpone — the epidural catheter should be removed
the surgical act in such cases,29but there are no when the coagulatioIn times are back again to
data which support this recommendation,33 normal and the patient should be accurately
D
and, therefore, a decision shall be made case monitored for at least 12 h after the removal.
by case, evaluating costs and benefits. So far, from the data of the literature it is not
The heparinisation may be continued also possible Eto evaluate the specific risk associ-
during the postoperative period with a con- ated with this technique.36-39 According to a
tinuous infusion such as to extend the aPTT complex mathematical calculation of the
M
by 1.5-2 times its basic value. Obviously, the probability of appearance of a rare event,
bleeding risk in these patients is increased.4 effected by Ho et al.®,40 based on a total of
In the survey reported by Vandermeulen et 4.583 epidural and 10.840 spinal anaesthe-
al.,750% of the haematomas appeared at t he sias without comTplications, the incidence of
removal of the catheter. In these patientAs, the the event might be 1:1.528 for the epidural
heparin infusion shall be interrupted 2-4 h and 1: 3.610 for the spinal anaesthesia. There
H
before the removal and an accurate moni- are controversial data on the risk/benefit ratio
V
toring of the sensitivity and the mobility of the of such techniques, referred to the surgical
lower limbs shall be made every 2 h, for at ouGtcome of these patients.41
least 12 h after removal.34R
At this time, from the published data and
Low doses of unfractioned heparin heparin by
from the long clinical experience on a high
I subcutaneous injection
number of patientsE, the use of local-region-
al techniques during a systemic heparinisRation Low doses of unfractioned heparin heparin
does non appear to involve significant risks;32 are a widely used method of anti-throm-
N
however, in these cases it is advisable to per- boembolic prophylaxis in general, orthope-
Y
form a particularly accurate neurological dic, and urologic surgery.42 Subcutaneous
monitoring, using reduced concentrations administration of 5000 UI every 12 h has
I
and doses of local anaesthetic. been widely used for many years, and
P
M although about 2-4% of the patients under-
going this therapy may show a therapeutic
Complete anticoagulation during a car-
O anticoagulation or a reduction of the
diopulmonary by-pass
platelets,30the complications connected with
Already in 1998, in the ASRA guidelines,12 this therapy are few.32
there was aC discussion of the risk/benefit of Three wide-range audits carried out in
the epidural analgesic anaesthesia in patients Denmark,43 in the United Kingdom and in
undergoing a cardio-pulmonary by-pass. So Scotland 44 and in New Zealand 45 have
far, there are no data about haematoma asso- shown that the therapy with calcium heparin
ciated with this technique in such patients. It is not considered normally as a contraindi-
is, however, certainly necessary to follow cation to the performance of a central block.
some recommendations:35 There have been published only 4 cases of
— the central block should be avoided in haematoma during the therapy with unfrac-
patients with concomitant coagulopathies tioned heparin, 3 epidural 7and 1 subarach-
from any cause; noidal,46 consequent to a central block.
— the surgical act should be postponed Precedent recommendations suggested to
by 24 h in case of traumatic puncture; perform the block 2 h after the administration
698 MINERVA ANESTESIOLOGICA Settembre 2006