[Carotid endarterectomy under remifentanil].
OBJECTIVE
Carotid endarterectomy can be performed under general or locoregional anesthesia. If locoregional anesthesia is chosen, the state of awareness of the patient allows for direct viewing of the effect of vascular clamping of the corresponding neurological territory. We present the results of an anesthetic procedure using only an analgesic in patients who were intubated and ventilated but with a level of consciousness that allowed us to view the effect of carotid clamping on motor functions.


METHODS
Forty-eight patients, ASA II-III, underwent surgical carotid endarterectomy. The anesthetic protocol began with preoxygenation for 2 min; induction with remifentanil 0.75-1 microgram kg-1 for 2 min., followed by perfusion of 1 microgram/kg-1.min-1 of remifentanil and propofol 1 microgram/kg-1; and orotracheal intubation by local anesthesia of the glottis with 5% lidocaine spray. Ventilation was with FiO2 100%, FR 12 min. and VT 8 ml. kg-1. For maintenance the dose of remifentanil was regulated to obtain a coordinated motor response (maximum 1.5 microgram/kg-1.min-1, minimum 0.35 microgram/kg-1. min-1). For all patients we monitored hemodynamics continuously and non-invasively, including aortic output by the transesophageal Doppler echocardiography.


RESULTS
The objective of anesthesia was reached in all the patients. The most common hemodynamic alterations were bradycardia (28), arterial hypotension (25), elevated blood pressure (3) and altered aortic output. All changes were corrected quickly with the treatment used, guided by the evolution of hemodynamic parameters. Postanesthetic recovery came in less than 4 min. The only episodes of hyper -and hypotension consisted of a few episodes of mild hyper- (12) and hypotension (1), which were soon corrected. No alterations attributable to hemodynamic instability occurred. During surgery, an intracarotid shunt was necessary in only one patient. Three suffered surgically-related neurological complications after the operations. No complications could be attributed to anesthesia.


CONCLUSIONS
An advantage of this technique is that the duration of anesthesia is not limited, with adequate ventilation and maintenance of an adequate state of consciousness for clinical evaluation of the repercussions of carotid clamping. Hemodynamic monitoring detected the appearance of imbalances requiring therapeutic intervention. The procedure is interesting provided it is performed according to a strict protocol, with continuous clinical and instrumental monitoring of the patient's status.
Muchada
R
R
Departamento de Anestesiología y Reanimación, Clínica Mutualista E. André, Lyon, Francia. muchada@lyon151.inserm.fr
Lucchesie
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G
D000368:Aged; D000369:Aged, 80 and over; D000525:Alprazolam / Q000008:administration & dosage; D000762:Anesthesia Recovery Period; D000771:Anesthesia, Intravenous; D018686:Anesthetics, Intravenous / Q000008:administration & dosage / Q000009:adverse effects; D001919:Bradycardia / Q000139:chemically induced; D002302:Cardiac Output / Q000187:drug effects; D016894:Endarterectomy, Carotid; D005260:Female; D006439:Hemodynamics; D006801:Humans; D006919:Hydroxyzine / Q000008:administration & dosage; D006993:Hypnotics and Sedatives / Q000008:administration & dosage; D007022:Hypotension / Q000139:chemically induced; D007431:Intraoperative Complications / Q000139:chemically induced; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative; D010880:Piperidines / Q000008:administration & dosage / Q000009:adverse effects; D011183:Postoperative Complications / Q000139:chemically induced; D011229:Preanesthetic Medication; D015742:Propofol / Q000008:administration & dosage; D000077208:Remifentanil; D016896:Treatment Outcome
D018686:Anesthetics, Intravenous; D006993:Hypnotics and Sedatives; D010880:Piperidines; D006919:Hydroxyzine; D000077208:Remifentanil; D015742:Propofol; D000525:Alprazolam