Cocaine abuse is increasing, particularly among young people. It is no longer a drug used exclusively by higher socio-economic groups. This review highlights the dangers of both acute and chronic cocaine abuse and its lethal potential even on the first encounter. The systemic effects of cocaine are described along with the possible pathology that may present itself to the attending clinician.

Background and objective: Operating room management structures and interrelationships both within the operating suite and with other departments in the hospital can be very complex. Several different professional and support groups are represented that often have infrastructures of their own that may compete or conflict with the management hierarchy in the operating room. Today, there is often little actual management of the operating suite as an entity. We surveyed current operating room management in Switzerland.

Methods: A questionnaire was sent to the chief anaesthesiologists of all public hospitals in Switzerland. It asked for information about the structure, organization and management of operating rooms as well as respondents’ opinions and expectations about management. Derived from both the literature and the results of the survey, a ‘stages of excellence’ model of best practice was developed.

Results: The overall response rate was 70%. Most anaesthesiologists were unsatisfied with current management policies and structures in their operating rooms. Of the hospitals questioned, 40% did not have an information system at all for the operating rooms. The remaining 60% had an information system that allowed rough scheduling in 71%, but only a few had more sophisticated systems that enabled dynamic scheduling (19%), user-defined conflict checking (5%), administration of a subsequent patient transfer station (postanaesthesia care units, intensive medical care, intensive care units) (10%) or other more advanced uses. All hospitals questioned offered some type of ambulatory surgery in a ‘hospital-integrated’ manner (i.e. use of the same operating room for both in- and outpatient surgery), but none had implemented a more efficient system where outpatient surgery was performed in separate facilities.

Conclusions: Current management of the operating room in Switzerland is far from best-practice standards.

Background and objective: Ventilation of the lungs with positive end-expiratory pressure during pneumoperitoneum has been shown to improve the arterial partial pressure of oxygen. The implications of spontaneous breathing on pulmonary gas exchange remain unknown in this setting. We therefore sought to examine the influence of pressure-support ventilation with spontaneous breathing on gas exchange during simulated laparoscopy.

Methods: Ten pigs were subjected to pneumoperitoneum at a pressure of 15 cmH2O. Animals received, in a random order, pressure-support and pressure-controlled ventilation for 60 min per mode. Inert gas and haemodynamic measurements were performed before changing to a subsequent mode.

Results: Pressure-support ventilation was more efficient than pressure-controlled ventilation regarding perfusion of normal VA/Q lung areas (78 ± 4% vs. 72 ± 5%) (P < 0.05), alveolar-arterial partial pressure of oxygen difference (9.73 ± 1.3 vs. 11.2 ± 1.2 kPa) and arterial partial pressure of oxygen (14.93 ± 1.6 vs. 13.7 ± 2.0 kPa) (P < 0.05).

Conclusions: Pressure-support ventilation resulted in significantly better gas exchange than pressure-controlled ventilation in this model of simulated laparoscopy.

Background and objective: Induction of general anaesthesia in combination with positive-pressure ventilation is often associated with a significant decrease of arterial pressure. A decreased preload may contribute to this phenomenon. The aim was to investigate whether a change in cardiac filling occurs following the induction of general anaesthesia with sufentanil under typical clinical conditions.

Methods: Fifteen patients scheduled for elective coronary bypass grafting were studied immediately before surgery. In addition to standard monitors, a transpulmonary double-indicator dilution technique measured in vivo intrathoracic blood volume, global end-diastolic volume and total circulating blood volume. For induction of anaesthesia 2 μg kg−1 sufentanil was given. Measurements were performed awake and after the induction of anaesthesia, intubation and mechanical ventilation of the lungs.

Results: To maintain arterial pressure during the induction period within −20% of baseline pressure, on average 22 ± 6 mL kg−1 crystalloids and 8 ± 6 mL kg−1 colloids were given. Despite these amounts of fluid, cardiac filling was decreased, whereas circulating blood volume increased significantly. Both central venous pressure and pulmonary capillary wedge pressure increased.

Conclusions: Induction of general anaesthesia with positive-pressure ventilation is regularly associated with a blood volume shift from intra- to extrathoracic compartments. Even in low-dose opioid monoanaesthesia with sufentanil – often regarded as relatively inert in haemodynamic terms – the phenomenon could be demonstrated as the primary cause of the often-observed decrease of arterial pressure. It seems, therefore, rationally justified to restore cardiac filling by generous administration of intravenous fluids, at least in patients with unaffected cardiac pump function. During induction of anaesthesia, central venous pressure and pulmonary capillary wedge pressure do not reliably indicate cardiac filling.

Background and objective: The aim was to examine the immediate effects of short-term anaesthesia on the different components of psychomotor performance of the upper extremity and cognitive functions, and to find out if there were any differences in the sensitivities of the different tests. The measured psychomotor aspects were simple reaction time, choice reaction time, speed of movement, index finger-tapping speed, co-ordination, visual spatial memory capacity, digit-symbol substitution and the Maddox Wing test.

Methods: The subjects were 30 female patients aged 24–50 yr who had been through a minor gynaecological operation. Anaesthesia had been induced with propofol and alfentanil. The measurements were mainly made with the HPM/BEP system, and the tests were performed 1 h before the anaesthesia and immediately after the wake-up.

Results: Short-term anaesthesia prolonged the simple reaction time by 7% and the choice reaction times by 25% (one-choice) and 7% (two-choice) and decreased the speed of movement by 10% (one-choice) and 19% (two-choice), index finger-tapping speed by 7% and co-ordination by 7%. In addition, visual spatial memory capacity decreased by 21%, digit-symbol substitution increased by 5% and the Maddox Wing test increased by 68%.

Conclusions: Based on the results, it seems that short-term anaesthesia reduces both signal processing at the central level, and motor control and co-ordination of movements at the peripheral level, and has a decreasing effect on motor performance in the above-mentioned aspects measured immediately after wake-up.

Background and objective: The safety of hypotension induced by sevoflurane and splanchnic organ blood flow remains to be clarified. The aim was to investigate the effects of sevoflurane-induced hypotension on systemic haemodynamics and splanchnic organ blood flows in dogs.

Methods: Mean arterial pressure was maintained at 60 mmHg by increasing sevoflurane concentrations. The renal, hepatic and pancreatic blood flows were measured by using the hydrogen clearance method.

Results: Hypotension induced by sevoflurane resulted in a 50% decrease of mean arterial pressure due to a 30% reduction in systemic vascular resistance associated with a 30% decrease in cardiac index. The mechanisms causing the lower cardiac index were produced by the decreases in heart rate and left ventricular dP/dtmax. Renal, hepatic and pancreatic blood flow were reduced, but the whole-body oxygen consumption did not change during the hypotensive period.

Conclusions: The haemodynamic changes induced by sevoflurane were caused by the suppression of arterial baroreflexes and myocardial depression, but splanchnic organ blood flows, though reduced, could provide adequate peripheral perfusion to meet the decrease in oxygen supply.

Background and objective: The epidural and subarachnoid spaces should be identified at the first attempt, since multiple punctures increase the risk of postdural puncture headache, epidural haematoma and neural trauma. The study aimed to describe the predictors of successful neuraxial blocks at the first attempt.

Methods: After institutional Review Board approval, 1481 patients undergoing spinal or epidural anaesthesia were prospectively enrolled. For each block we recorded: gender, age, height, weight, body habitus, anatomical landmarks (palpability of the spinous processes), spinal anatomy, patient positioning, premedication, needle type and gauge, approach, spinal level of the block, and the provider’s level of experience. Retrieval of cerebrospinal fluid or loss of resistance to saline or air identified the subarachnoid and epidural spaces, respectively. The outcome variable was the first attempt success or failure (whether or not the needle was correctly located with one skin puncture and produced adequate surgical anaesthesia). Backward stepwise logistic regression tested its association with the other variables.

Results: The first-attempt rate of success was 61.51%. Independent predictors (Odds ratio, 95% confidence limits) were the quality of anatomical landmarks (1.92 (1.57; 2.35)), the provider’s level of experience (1.24 (1.15; 1.33)) and the adequacy of patient positioning (3.84 (2.84; 5.19)).

Conclusions: The successful location of the subarachnoid or the epidural space at the first attempt is influenced by the quality of patients’ anatomical landmarks, the adequacy of patient positioning and the provider’s level of experience.

Background and objective: In this randomized, double-blind study, we aimed to investigate the effect of aminophylline on recovery from sevoflurane.

Methods: One-hundred ASA I–II patients scheduled for elective surgery were randomly divided into two groups receiving either NaCl 0.9% (Group 1, n = 50) or aminophylline 5 mg kg−1 (Group 2, n = 50). All patients were premedicated with atropine 0.01 mg kg−1 and midazolam 0.06 mg kg−1 intramuscularly. Anaesthesia was induced with propofol 2 mg kg−1 for muscle relaxation, and atracurium 0.5 mg kg−1 was maintained with sevoflurane 2% in 50% oxygen and nitrous oxide. Further atracurium (0.1 mg kg−1 was given when needed. Aminophylline or saline was given after sevoflurane was discontinued. Heart rate, mean arterial pressure, peripheral oxygen saturation, the duration of anaesthesia and recovery times (eye opening, verbal response, extubation and successful performance of arithmetical calculations) were recorded.

Results: There were no statistically significant differences in mean arterial pressure, peripheral oxygen saturation and anaesthesia time between the two groups. Heart rate increased significantly (P < 0.05) after aminophylline and was also higher than in the placebo group. Recovery times were significantly shorter (P < 0.001) in the patients receiving aminophylline.

Conclusions: Aminophylline speeded recovery after sevoflurane anaesthesia and it may have some advantage in anaesthesia practice for patients.

Background and objective: The intravenous anaesthetic propofol may become contaminated once the ampoules have been opened. The effect of lidocaine and cooling was tested on the bacterial contamination of propofol.

Methods: The study was performed in two parts. In Part 1, 1920 aliquots of propofol alone, and of a propofol-lidocaine mixture, were drawn into sterile syringes and stored at room temperature (24–26°C) or in the refrigerator (12–14°C). In Part 2, 1200 aliquots from opened ampoules of propofol alone, or as a propofol-lidocaine mixture, were stored at room temperature or in the refrigerator. Samples were aerobically cultured at 0, 1, 2, 4, 8, and 12 h.

Results: In Part 1, diphtheroid bacillus was isolated from one aliquot (0.06%). In Part 2, there was bacterial growth in both groups; the number of contaminated ampoules increased with time and it was 20–26% at 12 h. Diphtheroid bacilli and coagulase-negative staphylococci were the most frequent micro-organisms.

Conclusions: When propofol is stored in opened ampoules, the bacterial contamination rate is high. Adding lidocaine, or storing opened ampoules at 12–14°C, does not affect the contamination rate, except during the first few hours. It is advisable to draw propofol aseptically into a syringe in an amount that can be used during one procedure.