Preoperative volume expansion improves tolerance to carotid artery cross-clamping during endarterectomy.
OBJECTIVE
The benefit of carotid endarterectomy for carotid artery stenosis relates to both appropriate patient selection and careful surgical technique. Critical to the latter is the ability to afford intraoperative neuroprotection during carotid cross-clamping, although the optimal strategy to assure this protection remains debated. This report describes the impact of adding preoperative colloid volume expansion to a surgical algorithm that includes electroencephalographic (EEG) monitoring and barbiturate-induced burst suppression for EEG lateralization refractory to hypertension.


METHODS
The incidence of ischemic EEG change during carotid cross-clamping was observed. The results of an initial series of patients (n = 45) reported before incorporation of volume expansion were compared with the results of the current series (n = 155) of carotid endarterectomies, which included preoperative volume expansion with 6% hetastarch (500 or 1000 cc).


RESULTS
With preoperative volume expansion, there was a 40% decrease in the incidence of EEG lateralization during carotid cross-clamping (17.4 versus 28.9%, P < 0.05) and a 63% decrease in the EEG lateralization refractory to induced hypertension (5.8 versus 15.6%, P < 0.05). The combined perioperative stroke and death rate was 1.3%.


CONCLUSIONS
These results support the use of preoperative colloid volume expansion in carotid endarterectomy as a means of increasing the cerebral tolerance to carotid cross-clamping.
Gross
C E
CE
Department of Surgery, University of Vermont, Burlington 05405-0068, USA.
Bednar
M M
MM
Lew
S M
SM
Florman
J E
JE
Kohut
J J
JJ
D000759:Adjuvants, Anesthesia / Q000008:administration & dosage*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002545:Brain Ischemia / Q000175:diagnosis / Q000517:prevention & control; D016893:Carotid Stenosis / Q000175:diagnosis / Q000601:surgery*; D004292:Dominance, Cerebral / Q000187:drug effects; D004569:Electroencephalography / Q000187:drug effects; D016894:Endarterectomy, Carotid / Q000379:methods*; D005260:Female; D006801:Humans; D006895:Hydroxyethyl Starch Derivatives / Q000008:administration & dosage*; D007431:Intraoperative Complications / Q000175:diagnosis / Q000517:prevention & control; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative; D018696:Neuroprotective Agents / Q000008:administration & dosage*; D010424:Pentobarbital / Q000008:administration & dosage*; D010952:Plasma Substitutes / Q000008:administration & dosage*; D010953:Plasma Volume / Q000187:drug effects; D012307:Risk Factors
D000759:Adjuvants, Anesthesia; D006895:Hydroxyethyl Starch Derivatives; D018696:Neuroprotective Agents; D010952:Plasma Substitutes; D010424:Pentobarbital