The effects of hydroxyethyl starch on blood coagulation were investigated in 20 patients undergoing surgery to determine whether its use places recipients at risk of haemorrhage or thrombosis. The partial thromboplastin times are significantly prolonged; factor VIII activities and fibrinogen levels are decreased. After infusion of hydroxyethyl starch, no significant differences were detected in platelet count or prothrombin time. A decreased platelet aggregation was also found after the infusion of hydroxyethyl starch. According to our results, hydroxyethyl starch can cause haemorrhagic problems in patients when administered as a colloidal volume-expanding agent.

The present study was undertaken to evaluate the impact of a new procedure for eliciting informed consent by patients undergoing minor surgical procedures, in which the choice between general anaesthesia (GA) and regional anaesthesia (RA) was possible. In this prospective study, two randomly selected groups of patients were compared: study group (SG), 52 patients, received from the nurse before the preoperative interview, a list of seven questions, which they were invited to ask the anaesthetist; while the control group (CG), 73 patients, did not receive any suggested questions. There were two end points: the proportion that chose RA and the number of questions actually addressed to the doctor at the preanaesthetic interview. Psychological aspects were taken into account by collecting the Hospital Anxiety and Depression (HAD) scale before the preanaesthetic interview. Satisfaction with the interview was recorded using a telephone questionnaire 2 weeks after the operation. The results from the two groups were compared by calculating the odds ratio according to Mantel–Haenszel and by logistic analysis. Altogether, 71.2% of the patients chose RA without any difference between the groups. The average number of questions asked by each SG patient was higher than for the CG (1.67 vs. 0.96). The satisfaction level was similar in the two groups. Our list of questions was designed to facilitate patient autonomy. It offered an aid to those requesting more information and assisted communication. The method did not change the proportion who chose a specific kind of anaesthesia, but does seem to improve patient participation in the decision-making process.

The reduction in propofol-induced pain on injection caused by the addition of lignocaine results mainly from a drop in pH, which reduces the concentration of propofol in the aqueous phase of the emulsion. It is not an effect of the local anaesthetic per se. Propofol emulsion mixed with lignocaine destabilizes within hours. We mixed 10 parts of propofol 1% emulsion with one part of 0.0064 m HCl or 0.013 m HCl, respectively. These mixtures were stored for 3 months and compared with a freshly prepared solution of propofol 1% emulsion and saline, in the same proportion, regarding their ability to induce anaesthesia in the rat. There was no significant difference in the amount of propofol required to induce anaesthesia, nor was there any difference in recovery time between the three groups.

As elevated endothelin-1 (ET-1) levels have been reported in systemic inflammatory diseases, the role of ET-1 as a promoter of inflammatory reactions is currently under investigation. The purpose of this study was to investigate the potential influence of ET-1 on systemic vascular pressure and immune function in terms of blood clearance and organ distribution of injected Escherichia coli in a rabbit model. To enable quantification of the clearance process, defined numbers of exogenous E. coli (108 cfu) were injected intravenously 60 min after starting the infusion of ET-1 (0.2 μg kg−1 min−1; n=9) or after saline infusion (controls, n=9). Parameters monitored were arterial blood pressure, airway pressure, serum lactate concentrations and rates of bacterial elimination from the blood. At 180 min after E. coli injection, the animals were killed, and tissue samples of liver, kidney, spleen and lung were collected for bacterial counts. ET-1 infusion produced an increase in mean arterial pressure (83.9±3.9 mmHg vs. 50.1±4.1 mmHg at 120 min; P< 0.01) associated with higher serum lactate concentrations (12.6±1.3 vs. 5.4±0.3 mg dL−1; P< 0.001) and a delayed bacterial elimination from the blood compared with controls. Furthermore, there was increased colonization of the lungs (3.6±0.5×103 cfu vs. 745±120 cfu; P<0.01), spleen (142.4±45.4×103 cfu vs. 22.7±5.2×103 cfu; P<0.05) and kidney (758±329 vs. 357±151 cfu; NS), reflecting a reduced bacterial killing function.

We have investigated the cardiovascular and plasma noradrenaline response to surgical incision under sevoflurane anaesthesia and determined the end-tidal concentration of sevoflurane that blocks the adrenergic response or responses to surgical incision (MACBAR) and changes in mean arterial pressure (MAP) in response to surgical incision (MACBCR) in 50% of women. We randomly assigned 64 female patients, aged 20–49 years, to eight groups according to end-tidal sevoflurane concentration: 5.0%, 5.5%, 6.0%, 6.5%, 7.0%, 7.5%, 8.0% and 8.5%. All patients received only sevoflurane anaesthesia. An increase of 10% or more from prestress (incision) values of MAP or plasma noradrenaline concentration was considered a positive response. The probability of no response to stress was analysed using logistic regression to obtain the probability of no response vs. end-tidal sevoflurane concentration and the best-fit curve from the maximum likelihood estimators of the model parameters. MACBAR (mean±SE) was 8.0±0.2%, MACBCR was 7.9±0.2%. However, such high doses of sevoflurane cannot be used clinically because of their high toxicity. It may be preferable to combine sevoflurane with other anaesthetics to reduce haemodynamic responses to strong stimulation.

In a double-blind, randomized, controlled study, 61 patients who received a standardized anaesthetic for day case arthroscopic knee surgery were studied. Group T (n=31) received tramadol 1.5 mg kg−1, and group F (n=30) received fentanyl 1.5 μg kg−1 at the induction of anaesthesia. All patients also received 20 mL of intra-articular bupivacaine 0.5% at the end of surgery. Assessments were made of pain at rest and on movement, analgesic requirements and side-effects at hourly intervals up to 6 h and by means of a postal questionnaire at 24 h and 48 h post-operatively. Group F had higher pain scores than group T at 4 h only [VAS 3.3 (1.6–5.5) vs. 2.4 (1–4), P=0.039, respectively; median (interquartile range)]. There were no other significant differences between the groups in terms of pain scores, supplemental analgesic requirements or incidence of side-effects. We conclude that tramadol offers little benefit clinically compared with fentanyl when used at induction of anaesthesia for day case arthroscopic knee surgery. Further studies are indicated in patients with more severe pain to determine the role of tramadol in post-operative analgesia.

A prospective, double-blind, randomized, controlled study was undertaken to compare the perioperative analgesic and recovery characteristics of equipotent doses of tramadol, pethidine and nalbuphine (3.0 mg kg−1, 1.5 mg kg−1 and 0.3 mg kg−1 respectively) with placebo (saline 0.02 ml kg−1) given at induction of anaesthesia in 152 ASA I children and young adults undergoing tonsillo-adenoidectomy. Premedication (temazepam and diclofenac), induction and maintenance of anaesthesia (thiopentone, atracurium, nitrous oxide and isoflurane), with controlled ventilation, were standardized. Variables monitored were heart rate (HR) and systolic arterial pressure (SAP) during surgery, time to recovery of spontaneous respiration at the termination of anaesthesia and restlessness, time to awakening, sedation and emesis in the recovery unit. Increases in HR or SAP >33% of baseline during surgery were treated with esmolol 2.0 mg kg−1 intravenously (i.v.) and restlessness during recovery was treated with the same opioid i.v. given with anaesthesia, or pethidine i.v. in the placebo group. With placebo, there was a high requirement for esmolol during surgery and for pethidine in the recovery ward. Tramadol did not reduce the rate of intra-operative treatment with esmolol, but reduced the tramadol requirement during recovery (P<0.05). Pethidine and nalbuphine reduced the intra-operative esmolol requirement more significantly (P<0.025 and P<0.005 respectively) and the need for treatment during recovery with opioids (P<0.005 each). The time to recovery of spontaneous respiration at the end of anaesthesia was only delayed by pethidine. Other recovery variables were similar, except that restlessness–pain scores were reduced by tramadol (P<0.02), pethidine (P<0.005) and nalbuphine (P<0.005). These results suggest that pethidine 1.5 mg kg−1 and nalbuphine 0.3 mg kg−1 given with induction of anaesthesia provide better analgesia during and after tonsillo-adenoidectomy than does tramadol 3.0 mg kg−1. The delay to recovery of spontaneous respiration with pethidine suggests a greater safety profile of nalbuphine and tramadol.

In this study the effects of γ-hydroxybutyrate/fentanyl on cerebral blood flow velocity (CBFV) (as measured in the middle cerebral artery by transcranial Doppler ultrasonography) and on cerebrovascular carbon dioxide reactivity were investigated. Mean CBFV (̇Vmean) and haemodynamic responses were recorded in 12 non-neurosurgical patients before, during and after induction of general anaesthesia with γ-hydroxybutyrate (GHB) (20 min constant rate infusion of 100 mg kg−1). Two patients were excluded, one because of bradycardia and the other because of severe myoclonia. During the infusion of GHB, normocapnia was maintained by manually assisting ventilation as necessary. The infusion of GHB did not affect ̇Vmean [awake: 57±12 cm s−1 (mean±SD); 22.5 min: 62±15 cm s−1, NS difference] or mean arterial blood pressure (MAP) (awake: 97±12 mmHg; 22.5 min: 89±10 mmHg, NS). This suggests that cerebral blood flow velocity is unaltered by an anaesthetic dose of GHB. Twenty-five minutes after the start of GHB, fentanyl 3 μg kg−1 and vecuronium 0.1 mg kg−1 were given, the trachea was intubated and the lungs were mechanically ventilated to maintain end-tidal Pco2 of 4.6±0.4 kPa (30 min). At 30 min after the start of the GHB infusion, ̇Vmean and MAP decreased to 38±10 cm s−1 and 76±12 mmHg (both P<0.05 vs 22.5 min) respectively. After adjusting the ventilation to achieve hypocapnia (40 min: end-tidal Pco2 3.5±0.2 mmHg), ̇Vmean decreased to 29±7 cm s−1, while MAP did not change. This allowed the relative vasoreactivity (percentage change in ̇Vmean/0.133 kPa change in the end-tidal Pco2 from normocapnia to hypocapnia) to be estimated as 2.7±1.6% 0.133 kPa−1. This suggests that cerebrovascular response to CO2 during γ-hydroxybutyrate/fentanyl anaesthesia is maintained.

We report a case of surgical transsection of the nasoendotracheal tube during a Lefort I maxillary osteotomy, resulting in severe intra-operative ventilatory difficulties. The management of this problem and a brief review of the literature are presented.

This case report describes the clinical course of a patient who inadvertently received a massive intrathecal cefazoline overdose through a lumbar drain, which had been placed after trans-sphenoidal surgery for a pituitary adenoma. She received high-dose barbiturate therapy and was monitored with electroencephalography (EEG), somatosensory evoked potentials (SSEP), brainstem auditory evoked potentials (BAEP) and transcranial Doppler ultrasound (TCD). No cerebrospinal fluid (CSF) exchange was performed, but CSF was drained continuously with daily CSF-cefazoline level monitoring. Despite the extremely toxic dose, the patient soon recovered completely.