Absence of explicit and implicit memory in unconscious patients using a TCI of propofol.

BACKGROUND: Episodes of implicit memory have been described during propofol anaesthesia. It remains unclear whether implicit memory is caused by short periods of awareness or occurs in an unconscious subject. METHODS: Sixty patients were randomized in an experimental group (EG), a control group (CG) and a reference group (RG). Loss of consciousness (LOC) was obtained by progressive stepwise increases of propofol using a target-controlled infusion device (Diprifusor, Alaris Medical Systems, San Diego, CA). A tape containing 20 words was played to the patients in the CG before the start of anaesthesia and to the patients in the EG at a constant calculated concentration of propofol associated with LOC. The tape was not played to the patients in the RG. Three memory tests were performed postoperatively. RESULTS: Explicit and implicit memories were evidenced in the CG but not in the EG. CONCLUSION: In our group of young ASA I/II patients, in the absence of any noxious stimulus, no implicit or explicit memory was found when the calculated concentration of propofol using a Diprifusor was maintained at the level associated with LOC.

[The anesthesiology-recovery department]. / Le Service d'Anesthésiologie Réanimation.

The Department of Anesthesiology and Reanimation is organised in units with clinical activities, which include the pre-operative care of patients, anesthesiological care and immediate post-operative supervision. Two post-operative treatment rooms also form part of the department. The main fields of research of the various units result from collaborations with other departments of Hôpital Erasme, in particular with regard to the development of advanced techniques or fit within the confines of the speciality.

Single i.v. bolus dose of ondansetron in the prevention of postoperative nausea and emesis.

In this placebo controlled, double blind multicentre study, the efficacy and safety of a single i.v. bolus dose of ondansetron 4 mg were evaluated in the prevention of postoperative nausea and vomiting (PONV), which remains one of the most unpleasant side effects experienced by patients postoperatively. The study population included patients having general anesthesia and undergoing major gynecological or elective abdominal surgery by laparoscopy. Thirty three percent of placebo-treated patients had at least one emetic episode over 24 hrs compared with 21% in the ondansetron group (p = 0.03). Forty two percent of placebo-treated patients experienced nausea in the 24 hours post-recovery period, compared to 27% of patients treated with ondansetron 4 mg (p = 0.01). Several factors appeared to be associated with an increased risk of developing PONV, namely gender (female), type of surgery (gynecological), experience of previous PONV and duration of anesthesia; the use of propofol was not a significant factor. Ondansetron was well tolerated, with no side effect being reported as a significant problem.

Intramuscular buprenorphine for pain relief after abdominal surgery: a comparison between on-demand and prophylactic administration.

The efficacy of intramuscular (i.m.) buprenorphine, given either at the end of anaesthesia or to treat established pain was investigated on 60 patients scheduled for major abdominal surgery receiving isoflurane anaesthesia. During skin closure (1st injection), patients were given either i.m. buprenorphine 0.3 mg or i.m. saline. Pain was assessed every hour in the post-anaesthetic care unit by the patient using a numerical rating scale. Patients were given 0.3 mg of i.m. buprenorphine (2nd injection) on request. The study was completed when a 3rd injection of i.m. buprenorphine 0.3 mg was required. The overall impressions of patients, nurses and doctors were recorded on a scale ranging from 1 to 5 at the end of the study. The interval between the 1st and 2nd injection was significantly longer (P < 0.001) following administration of buprenorphine (5 h 18 min) than saline (1 h 3 min). Mean pain scores were significantly lower after buprenorphine compared to saline (P < 0.01). There was no significant difference in duration of action or mean pain scores following buprenorphine given either at wound closure or on first demand. However, overall impressions recorded at the end of the study were significantly better when buprenorphine was given preventatively. Prophylactic buprenorphine proved to be a suitable analgesic after an inhalational anaesthesia.

Continuous spirometry for detection of double-lumen endobronchial tube displacement.

Flow-volume and pressure-volume loops were measured with continuous spirometry in 49 patients in whom the trachea was intubated "blindly" with a double-lumen endobronchial tube for thoracic surgery. Nineteen endobronchial tubes were malpositioned by fibreoptic bronchoscopic criteria; 63% of these were suspected because of the configuration of the spirometric loops. During positioning of the patient and during operation, 34.7% of the endobronchial tubes migrated from the initially correct or corrected position. The secondary displacements were identified by abnormal loop configurations and confirmed with fibreoptic bronchoscopy. Continuous spirometric monitoring is helpful in detecting endobronchial tube displacement during intubation and surgery.

Ventilatory effects of pneumoperitoneum monitored with continuous spirometry.

Inspiratory and expiratory tidal volume, peak and plateau airway pressure, compliance of the respiratory system, pressure-volume and flow-volume loops were monitored continuously and recorded in seven women undergoing laparoscopy with carbon dioxide insufflation to an intra-abdominal pressure of 1.6 kPa. All patients were anaesthetised using a total intravenous technique and a constant minute ventilation was maintained. Peak airway and plateau airway pressures increased by 50% and 81% respectively, whilst the compliance of the respiratory system decreased by 47% during the period of increased intra-abdominal pressure. Following release of the pneumoperitoneum, peak and plateau pressures remained elevated by 37% and 27% respectively, and the compliance was 86% of the pre-insufflation value. On-line monitoring of respiratory volumes, pressures and compliance may be helpful during general anaesthesia for laparoscopic procedures to avoid the potential harmful effects of increased airway pressures occurring with increased intra-abdominal pressure.

The effect of oral ondansetron in the prevention of postoperative nausea and vomiting after major gynaecological surgery performed under general anaesthesia.

The efficacy and safety of ondansetron in preventing postoperative nausea and vomiting following major gynaecological surgery was evaluated in this multicentre, double-blind study. A total of 243 patients were randomised to receive three doses of oral ondansetron 8 mg or matching placebo at 8-hourly intervals, with the first dose being given an hour before surgery. A standard general anaesthetic technique was employed throughout. Nausea, vomiting and safety assessments were performed continuously during the 24 h postrecovery period. Of the 237 patients evaluated for efficacy, significantly fewer ondansetron 8 mg treated patients (65/117; 56%) experienced postoperative nausea and/or vomiting compared with placebo-treated patients (94/120; 78%) during the study period (p < 0.001). In addition, ondansetron 8 mg reduced the severity of nausea (p < 0.001) and the total number of vomiting episodes experienced (p < 0.001). Overall, ondansetron 8 mg was well tolerated and effective in preventing postoperative nausea and vomiting in this surgical setting.

Continuous noninvasive blood pressure monitoring during thoracic surgery.

To evaluate the usefulness of noninvasive blood pressure monitoring during thoracic surgery, blood pressure measurements obtained with the Finapres 2300 (Ohmeda, Boulder, CO) were compared with an intraarterial catheter system in 10 patients undergoing thoracotomy for lobectomy or pneumonectomy. The Finapres measurements were compared with pressure data obtained ipsilaterally from a radial artery catheter-transducer system. The waveforms were recorded using a strip chart recorder; the systolic (SBP) and diastolic blood pressures (DBP) were measured every 20 seconds on the paper trace. Precision and bias were calculated for SBP and DBP for each patient and for the pooled data, with the invasive blood pressure being considered the gold standard. A total of 1,861 measurement pairs were recorded, 938 pairs during one-lung ventilation. The Finapres underestimated SBP during two-lung ventilation, and overestimated SBP during one-lung ventilation. The precision was good and the biases were small, but there were wide individual variations. It is concluded that the Finapres can be useful in estimating the variability and following the trends of radial arterial blood pressure during thoracic surgery, and is an acceptable alternative to invasive blood pressure monitoring.

Epithelioid hemangioendothelioma of the liver following contact with vinyl chloride. Recurrence after orthotopic liver transplantation.

Malignant epithelioid hemangioendothelioma of the liver is a recently recognized and uncommon neoplasm of vascular origin. Few cases have been reported and the treatment remains therefore difficult to define. A relationship to oral contraceptive use has been suggested but no other toxic agents have been incriminated. We report here the first case occurring after a close contact with vinyl chloride. Because of wide hepatic destruction and serious portal hypertension with bleeding varices, the patient underwent orthotopic liver transplantation. After a disease-free interval of 20 months, he died from variceal hemorrhage and encephalopathy due to local tumor recurrence with portal thrombosis. Nevertheless, orthotopic liver transplantation remains the only hope of salvage when extensive liver destruction and life-threatening complications are present.

[Digestive system surgery in octogenarians]. / Chirurgie digestive chez l'octogénaire.

Between October 1, 1977 and June 30, 1983, 139 G.I. tract operations were performed in patients over 80 years-old. 45,3% were post-operatively admitted to the I.C.U.; the criteria for admission were emergency surgical interventions, the type and duration of the operation. The operative mortality was 15,8%. Contributory factors were the type of the intervention, its curative nature and the necessity for post-operative reanimation. The urgent nature of the intervention as well as the histology of the lesion had no bearing on the mortality. Local complications were noted in 34,5% of the cases and were mainly superficial and deep wound infections. General complications, mainly involving the cardio-pulmonary and urinary tract systems, occurred in 68,3% of the cases. Morbidity was mainly associated with the timing of the intervention.

[Proximal duodenopancreatectomy in the treatment of tumors of the bilio-pancreatic junction]. / La duodénopancréatectomie céphalique dans le traitement des tumeurs du carrefour biliopancréatique.

Between 1978 and 1983, 32 patients underwent a proximal duodeno-pancreatectomy for malignant lesions of the ampullary region on head on the pancreas. Pre-operative diagnosis was made by endoscopic cholangio-pancreatography, echography, tomodensitometry and arteriography. 14 patients underwent a pre-operative endoscopic bile drainage procedure. The operative mortality was 6,2% and the morbidity 43%; the intensity of the icterus as well as the preoperative bile drainage procedure did not change these factors significantly. The pre-operative diagnostic procedures permitted a clear definition of the extent of the tumor and retrospective analysis demonstrated their prognostic significance with regard to long-term survival. 11 patients are still alive. The presence of histologically proven metastases reduce significantly the duration of survival. Surgical resection is the best treatment for malignant tumors of the ampullary region and the head of the pancreas without local or distant metastases.

Use of labetalol during anesthesia for pheochromocytoma removal.

Labetalol, an alpha and beta adrenergic blocking drug, was used during anesthesia for removal of a very large pheochromocytoma which was predominantly epinephrine secreting. The 70-year-old female patient suffered from angina pectoris and chronic bronchitis. A preoperative treatment including an alpha-adrenolytic drug was administered but beta-adrenergic blockers were avoided because of the risk of cardiac decompensation and bronchoconstriction. During the operation, hypertensive peaks were easily controlled by bolus injections of labetalol 20 mg. The removal of the tumor was followed by a transient moderate hypotension. Heart rate remained stable throughout the operation. No hemodynamic problems occurred during the postoperative period. With regard to this case, a summary of the literature concerning the properties of labetalol is presented.