Severe complications such as spinal epidural haematoma and an array of adverse neurological events leading to temporary or permanent disability have been ascribed to central neuraxial blocks. Infections (meningitis, abscesses), chemical injuries and very rarely cerebral ischaemia or haemorrhage, or both, have also been ascribed directly or indirectly to spinal and/or epidural anaesthesia. Some case reports, and very few retrospective studies, have focused their attention on the fact that central nerve blocks can cause, albeit rarely, permanent damage to the spinal cord or nerve roots, or both. The cause of this damage in many cases remains unclear. The attention of investigators and practitioners is focused both on understanding the causative mechanisms of such accidents and in identifying 'alarm events' that can arise during the administration of a central block, if any. We reviewed the international literature for the neurological complications of central neuraxial blocks to identify some events that, if they occurred during the block procedure, could be perceived as dangerous.

Background and objective: Parallels exist between the coma associated with cerebral malaria and general anaesthesia. They both produce reversible loss of consciousness. In the case of cerebral malaria and in the absence of other complications, patients recover without sequelae. General anaesthetics are so designed that patients recover from their anaesthetics very quickly and show no ‘after effects’. This study compares brain function in these two clinical conditions by examining auditory- (AEPs) and median nerve somatosensory-evoked potentials (SEPs). The AEPs studied (waves Pa and Nb) are thought to arise from the primary auditory cortex and the median nerve SEPs (waves P15, N20, P25, N35, P45) from the pons, thalamus and primary somatosensory cortices.

Methods: Six comatosed patients with malaria (three males, three females) aged between 19 and 38 yr were studied in Zimbabwe. Their Glasgow Coma Scores on admission were 4, 3, 6, 7, 7 and 11. Their AEPs and median nerve SEPs were recorded daily over 4 days. The data were compared with those previously collected in the UK on patients and volunteers anaesthetized with desflurane, isoflurane, sevoflurane and propofol.

Results: In general, patients with cerebral malaria showed AEPs and SEPs similar to those of light to moderate anaesthesia i.e. 0.5–1.25 measure of anaesthetic potency (MAC), where 1 MAC is the minimum alveolar concentration necessary to prevent movement to surgical incision in 50% of patients. The appearance of the AEPs and SEPs bore no relationship to the degree of coma. The auditory brainstem-evoked response was retained in all degrees of coma, as would be expected. Otherwise, it would not be possible to interpret the waveform. In most instances, the early cortical complex Pa/Nb/Pb of the AER was present. When comatose patients emerged from malarial coma or were stimulated by talking loudly to them, they showed changes in the Pa/Nb/Pb complex similar to those seen on awakening from anaesthesia. The somatosensory-evoked response showed clear P15, N20 and P25 peaks at the expected latencies, and in some instances the waveforms of cerebral malaria and lightly anaesthetized volunteers were very similar.

Conclusions: The sensory-evoked responses of the cerebral malaria patients recorded in this study were not markedly different from those seen in light-to-moderately anaesthetized patients and volunteers. The profound depression of the AEPs and SEPs associated with deeper levels of anaesthesia were not seen, with the exception of one patient several hours before death.

Background and objective: The study was designed to compare the costs of propofol versus sevoflurane for the maintenance of the hypnotic component of anaesthesia during general anaesthesia, guided by the bispectral index, for gynaecological laparoscopic surgery.

Methods: Forty ASA Grade I—II female patients scheduled for gynaecological laparoscopy were randomly allocated to two groups. All patients received a continuous infusion of remifentanil (0.25 µg kg−1 min−1) for 2 min. Then anaesthesia was induced with propofol 1% at 300 mL h−1 until loss of consciousness. To guide the bispectral index between 40 and 60, Group 1 patients received propofol 10 mg kg−1 h−1 initially, which was increased or decreased by 2 mg kg−1 h−1 steps; Group 2 patients received sevoflurane, initially set at 2 vol.% and adjusted with steps of 0.2–0.4%. The time and quality of anaesthesia and recovery were assessed in two postoperative standardized interviews.

Results: Patient characteristics, the propofol induction dose, the bispectral index and the haemodynamic profiles during induction of anaesthesia, and its duration, were similar between the groups. In Group 1, 7.55 ± 1.75 mg kg−1 h−1 propofol and in Group 2, 0.20 ± 0.09 mL kg−1 h−1 liquid sevoflurane were used for maintenance. The cost for maintenance, including wasted drugs, was higher when using propofol (€25.14 ± 10.69) than sevoflurane (€12.80 ± 2.67). Postoperatively, recovery profiles tended to be better with propofol; however, the day after discharge no differences were found.

Conclusions: When applying the bispectral index to guide the administration of hypnotic anaesthetic drugs, propofol-based maintenance of anaesthesia was associated with the highest cost. A trend towards a better recovery profile was obtained with propofol. However, on the day after discharge, no differences in quality were observed.

Background and objective: The common parameters of the electroencephalogram quantify a shift of its power spectrum towards lower frequencies with increasing anaesthetic drug concentrations (e.g. spectral-edge frequency 95). These ad hoc parameters are not optimized for the content of information with regard to drug effect. Using semilinear canonical correlation, different frequency ranges (bins) of the power spectrum can be weighted for sensitivity to changes of drug concentration by multiplying their power with iteratively determined coefficients, yielding a new (canonical univariate) electroencephalographic parameter.

Methods: Electroencephalographic data obtained during application of volatile anaesthetics were used: isoflurane (n = 6), desflurane (7), sevoflurane (7), desflurane during surgical stimulation (12). Volatile anaesthetic end-tidal concentrations varied between 0.5 and 1.6 minimum alveolar concentration (MAC). The canonical univariate parameter and spectral-edge frequency 95 were determined and their correlation with the volatile anaesthetic effect compartment concentration, obtained by simultaneous pharmacokinetic—pharmacodynamic modelling, were compared.

Results: The canonical univariate parameter with individually optimized coefficients, but not with mean coefficients, was superior to the spectral-edge frequency 95 as a measure of anaesthetic drug effect. No significant differences of the coefficients were found between the three volatile anaesthetics or between the data with or without surgical stimulus. The coefficients for volatile anaesthetics were similar to the coefficients for opioids, but different from coefficients for propofol and midazolam.

Conclusions: The canonical univariate parameter calculated with individually optimized coefficients, but not with mean coefficients, correlates more accurately and consistently with the effect site concentrations of volatile anaesthetics than with spectral-edge frequency 95.

Background and objective: Multimodality treatment for patients with locally advanced primary or locally recurrent rectal cancer, including high-dose preoperative external beam radiotherapy, extensive surgery and intraoperative radiation therapy, decreases the local recurrence rates and improves survival. During this aggressive operation, the anaesthesiologist is faced with potential problems such as major transfusion requirements, hypothermia, intraoperative position changes, the need to transport the patient to the intraoperative radiation therapy applicator, and the risks associated with remote monitoring of the patient during the 10 min intraoperative radiation therapy application. The anaesthetic management and perioperative results were evaluated for the anaesthetic results and the complications.

Methods: One-hundred-and-six patients undergoing the multimodality treatment between February 1994 and March 2000 for locally advanced primary (n = 50) and locally recurrent rectal cancer (n = 56) were retrospectively evaluated for their anaesthetic results and complications.

Results: All patients were operated upon using a combination of general and epidural anaesthesia. The average duration of anaesthesia was 6 (range 3–10.5) h and the mean blood loss 3.6 (range 0.4–14) L. All patients recovered well from anaesthesia. Two patients (2%) died in the intensive care unit (34 and 48 days postoperatively) because of adult respiratory distress syndrome following postoperative haemorrhage. Severe haemorrhage during or after the operation was significantly related with the development of adult respiratory distress syndrome (P < 0.0001).

Conclusions: With adequate preoperative assessment and optimalization of the patient's condition, maintaining peroperative haemodynamic stability with the help of adequate remote monitoring, early and fast transfusion, and multidisciplinary communication, anaesthetic complications can be minimized.

Background and objective: Thiopental prolongs the QT interval more than propofol, and the two induction agents were compared in patients with subarachnoid haemorrhage predisposed to electrocardiographic abnormalities and cardiac dysrhythmias.

Methods: Twenty-nine patients were studied randomly. Anaesthesia was induced with either thiopental or propofol and fentanyl; vecuronium was used as a neuromuscular blocking agent. The electrocardiogram and arterial blood pressure were monitored from before the induction of anaesthesia to 2 min after endotracheal intubation.

Results: The median QT interval was at baseline 423 ms in the thiopental group and at 432 ms in the propofol group, and it increased in the thiopental group to 446 ms and decreased in the propofol group to 425 ms (P < 0.01 between groups). After induction and endotracheal intubation, the number of patients with increased QT dispersion was greater in the propofol group (P < 0.05). The incidence of cardiac dysrhythmias was similar in the study groups.

Conclusions: Thiopental and propofol are equally suitable for the induction of anaesthesia in patients with subarachnoid haemorrhage.

Background and objective: The study evaluated the manpower requirements in anaesthesia in Belgium until 2020. The basic intent was to estimate the need for anaesthesiologists in different hospitals because the number of medical students will be reduced to 700 in 2004 and to 600 in 2007 (numerus clausus), and the number of trainees in anaesthesia from 110 to 42 (best scenario) or to 21 (worst scenario). Simultaneous anaesthesia (more than one patient at the same time) is not allowed by our professional safety rules or by the Belgian Ministry of Public Health. The questions are: will we have enough anaesthesiologists in the next 20 years, and is there a need for nurses to administer anaesthesia? This professional title of nurse anaesthetist does not presently exist in Belgium.

Methods: Every registered anaesthesiologist in Belgium received a questionnaire about the manpower requirements in his or her institution expected over the next 20 years. The workload in the specialty was also considered.

Results: We received 154 replies from 186 different hospitals. The workload is definitely high: 10 h per day was devoted to clinical work and 4.6 h per week to administration. Belgium will need 51 anaesthesiologists each year after 2004, and 58 each year from 2010 to 2020.

Conclusions: Will anaesthesiologists accept their present high workload for the next 20 years? If not, the consequences will be serious. Three-quarters (75.4%) of the replies identified a need for more anaesthesiologists and considered that an anaesthesiologist supervising anaesthesia nurses for a number of patients simultaneously was a possible solution.