Background and objective The aim of this study was to determine possible age-associated differences in human blood pressure regulation during an immunological challenge in healthy subjects.

Methods Eight healthy young volunteers (median age 24 yr) and nine healthy elderly volunteers (median age 66 yr) received an intravenous bolus injection of Eschericia coli endotoxin (2 ng kg−1). Blood pressure, heart rate and core temperature were monitored during the first 7 h. Plasma catecholamine concentrations were measured at hourly intervals.

Results The elderly showed a significantly more pronounced decrease in mean arterial pressure 4–7 h after endotoxin administration compared with the young controls (anova; age × time; P < 0.0005). This mainly reflected a decrease in the systolic blood pressure in the elderly. The heart rate of both groups increased without difference between groups. Increased plasma epinephrine concentrations were found 2–3 h after endotoxin administration in both groups. Five hours after the endotoxin challenge, the epinephrine concentration had returned to control values in the elderly group only, in spite of decreased blood pressure.

Conclusion In conclusion, healthy elderly subjects fail to maintain a constant mean arterial pressure in response to the immunological challenge of endotoxemia.

Background and objective The purpose of this study was to investigate retrospectively what factors contribute to the development of the type of hyperlactatemia which may follow cardiopulmonary bypass despite well-maintained oxygen delivery and a normal perioperative course.

Methods The medical records of 124 patients undergoing elective cardiac surgery using cardiopulmonary bypass were reviewed. The patients were divided into a hyperlactatemia group (n = 34), where the serum lactate concentration was > 5.0 mmol L−1 perioperatively, and a normal lactatemia group (n=90), which comprised the remaining patients.

Results The duration of cardiopulmonary bypass in the hyperlactatemia group was significantly longer than for the normal lactatemia group. Significant differences of lactate concentrations between the groups, and significant elevations of serum lactate had been observed after the start of cardiopulmonary bypass. Oxygen extraction rates were significantly reduced during the period of cardiopulmonary bypass but, on the contrary, increased in the hyperlactatemia group after surgery. The area under the curve of mean arterial pressure consisted of 5-min interval plots during the initial period of cardiopulmonary bypass in the hyperlactatemia group. This was significantly smaller than for the normal lactatemia group. Weakly significant correlations between maximal lactate and duration of cardiopulmonary bypass, and especially the area under the curve, were observed.

Conclusions It is suggested that the pathophysiology observed is based on impairment of tissue oxygen utilization. The duration of cardiopulmonary bypass and especially the occurrence of hypotension at the start of the bypass period appears to be related to the development of lactic acidosis.

Background and objective Ischaemic colitis can be a serious complication after aortic surgery. The paucity of clinical symptoms makes its diagnosis particularly difficult and often delayed. Automated on-line tonometry is now proposed to monitor intestinal perfusion. This study was designed to assess the use of semi-continuous sigmoid-to-arterial [P(r-a)CO2] PCO2 gap monitoring in aortic surgery to detect colonic ischaemia.

Methods This prospective clinical study was realized at the University Hospital of Lille, France, including eight males scheduled for abdominal aortic aneurysm surgery. Intraoperative and postoperative P(r-a)CO2 values were compared with conventional monitoring and colonic mucosa aspect performed by sigmoidoscopy 48 h after surgery. Haemodynamic variables, O2 delivery (DO2), O2 consumption (VO2), O2 extraction (ERO2), lactate, P(v-a)CO2, P(r-a)CO2 were measured peroperatively and every 4 h during a 48-h postoperative period.

Results Intraoperative P(r-a)CO2 values increased significantly with the highest value (4.36 ± 3.42 kPa) observed during aortic clamping when DO2 was the most altered. P(r-a)CO2 continued to deteriorate after surgery with the maximal values between 8 (4.79 ± 3.85 kPa) and 12 (4.68 ± 3.26 kPa) h after surgery. This peak was associated with a significant ERO2 increase counterbalancing an increase of VO2 whereas DO2 tended to decrease. P(r-a)CO2 values began to decrease only at the end of the study. The highest values of P(r-a)CO2 were registered in patients with the most altered haemodynamic variables, severe ischaemic colitis along with higher hospital lengths of stay.

Conclusion Taken together, these data suggest that regional and automated capnometry may be easily used non-invasively to detect peroperative intestinal ischaemia in aortic surgery.

Background and objective The laryngeal tube is a variant of the oesophageal obturator airway. The manufacturer claims that it is an alternative to ventilation with a facemask, laryngeal mask or endotracheal tube. To date, published studies have only involved controlled ventilation. We wished to find out if its use in spontaneous ventilation was equivalent to using the laryngeal mask airway.

Methods We have compared the laryngeal tube with the laryngeal mask in a randomized prospective study involving patients breathing spontaneously under general anaesthesia. Criteria and a scoring system were used for the comparison. A sequential analysis chart with P=0.01 was chosen for each of two anaesthetists.

Results Only seven and 10 pairs of patients were required to indicate that the laryngeal tube was poorer at airway maintenance than the laryngeal mask. Of the 17 patients who had received the laryngeal tube, successful airway maintenance was only possible in seven. In the remaining 10 patients, the laryngeal tube was abandoned and the rescue airway was the laryngeal mask in all cases. All 17 patients randomized to the laryngeal mask were successfully managed.

Conclusions We conclude that the laryngeal tube is not a satisfactory device for management of the airway during spontaneous ventilation.

Background and objective Inflammatory liver dysfunction in rats leads to a prolonged vecuronium-induced neuromuscular blockade due to insufficient metabolism. A coexisting resistance against the drug partly counteracts this prolongation. The present study investigates the pharmacodynamics of atracurium whose metabolism does not depend on liver function.

Methods Male Sprague–Dawley rats (n = 14; 290 ± 30 g) were randomly allocated to either a group in which liver inflammation was induced by intravenous injection of 60 mg kg−1 heat-killed Corynebacterium parvum or to a control group. On day 5 after injection, liver function was assessed using the aminopyrine breath test. Under propofol anaesthesia, duration of action of atracurium (4.8 mg kg−1) was measured by evoked mechanomyography (stimulation of the sciatic nerve; contraction of the gastrocnemius muscle). Nitric oxide concentrations, as variables for the severity of the inflammation, were assessed by measurement of nitrite/nitrate plasma concentrations.

Results In C. parvum-injected rats, nitrite/nitrate plasma concentrations were increased (972 ± 597 vs. 25 ± 7 μmol L−1), the aminopyrine turnover was depressed (1.7 ± 0.4% vs. 3.5 ± 0.5%), and the atracurium-induced neuromuscular blockade was shortened (372 ± 128 s vs. 1081 ± 234 s).

Conclusions A systemic inflammatory response syndrome with liver dysfunction results in decreased sensitivity to atracurium. Further investigations are needed regarding a possible up-regulation of acetylcholine receptors or an increased protein binding of atracurium during sepsis to clarify reasons behind this phenomenon.

Background and objective This open, multicentre study compared the efficacy and safety of remifentanil with fentanyl during balanced anaesthesia with 0.8% isoflurane (end-tidal concentration) for major abdominal and gynaecological surgery, and the efficacy and safety of remifentanil for pain management in the immediate postoperative period.

Methods Two-hundred and eighty-six patients were randomized to receive remifentanil 1 μg kg−1 followed by 0.2 μg kg−1 min−1 (n = 98), remifentanil 2 μg kg−1 followed by 0.4 μg kg−1 min−1 (n = 91) or fentanyl 3 μg kg−1 (n = 97) at induction. Thereafter, the study opioids and isoflurane were titrated to effect during the operation.

Results Compared with fentanyl, remifentanil 2 μg kg−1 followed by 0.4 μg kg −1 min−1 reduced the incidence of response to tracheal intubation (30% vs. 13%, P < 0.01), skin incision (33% vs. 4%, P < 0.001) and skin closure (11% vs. 3%, P< 0.05), respectively. Patients receiving remifentanil 1 μg kg−1 followed by 0.2 μg kg −1 min−1 had fewer responses to skin incision than the fentanyl group (12% vs. 33%, P< 0.001), but the incidences of response to tracheal intubation and skin closure were similar. Significantly fewer patients in both remifentanil groups had ≥ 1 responses to surgical stress intraoperatively compared with fentanyl (68% and 48% vs. 87%, P < 0.003). The mean isoflurane concentrations required were less in both remifentanil groups compared with the fentanyl group (0.1%, P = 0.05). In remifentanil-treated patients, continuation of the infusion at 0.1 μg kg−1 min−1 with titration increments of ± 0.025 μg kg−1 min−1 was effective for the management of immediate postoperative pain prior to transfer to morphine analgesia. However, a high proportion of patients experienced at least moderate pain whilst the titration took place.

Conclusions Anaesthesia combining isoflurane with a continuous infusion of remifentanil was significantly more effective than fentanyl at blunting responses to surgical stimuli. Significantly fewer patients responded to tracheal intubation with remifentanil at 0.4 μg kg−1min−1, supporting the use of a higher initial infusion rate before intubation. Both remifentanil and fentanyl were well-tolerated, with reported adverse events typical of μ-opioid agonists.

Background and objective Female patients undergoing gynaecological procedures, especially laparoscopically, are at high risk of postoperative nausea and vomiting. No available antiemetic is entirely effective. This double-blinded randomized trial examines the efficacy and safety of tropisetron and metoclopramide in combination and compares the results with metoclopramide alone in laparoscopic gynaecological surgery.

Methods One hundred and twenty female patients scheduled for minor gynaecological laparoscopy, aged 27–43 years, were randomly allocated to receive pretreatment with metoclopramide 10 mg intravenously (n = 57) or tropisetron 5 mg with metoclopramide 5 mg (n = 63).

Results Fewer patients in the combined treatment group experienced postoperative nausea and vomiting (14% vs. 37%, P = 0.008) or needed rescue antiemetic treatment (3% vs. 16%, P = 0.038). No significant adverse events were observed.

Conclusions The combination of the antiemetics was superior, which is probably explained by the fact that the two drugs have different sites of action, thus preventing emesis by blocking different pathways.

Patient attitudes to medical information are changing. We audited patient attitudes to an information leaflet provided at the preadmission clinic as part of standard day-case protocol. The booklet is a simplified version of the booklet Anaesthesia and Anaesthetists – Information for Patients and Relatives published in London, UK, by the Association of Anaesthetists of Great Britain & Ireland. One hundred and three patients were surveyed before surgery over a 2-month period using an anonymous questionnaire. Of the 96% of patients who read the booklet provided, 99% found it helpful to some degree. Thirty-five per cent of patients found it worried them. Thirty-two per cent discussed the information with others but only 3% discussed the information provided with the anaesthetist. Although patients like to receive information about the process of anaesthesia, we must be careful that by providing it in an inappropriate form, e.g. as a leaflet, we do not increase their preoperative anxiety.

A case is presented in which memory of events during emergence from anaesthesia resulted in serious psychological sequelae. Communication with patients should begin almost immediately after anaesthesia has been terminated and should have prevented this unfortunate incident.