The still ever increasing demand for sedation and/or analgesia for diagnostic and therapeutic procedures puts high pressure on anaesthesia care providers all over Europe. Since the capacity to provide that service by anaesthetists is limited in most European countries, guidelines for non-anaesthetist doctors who want to sedate patients on a high-quality level and especially in a safe way are mandatory. This paper, produced by a working party of the European Board of Anaesthesiology of the European Union of Medical Specialists (EUMS/UEMS), gives direction to those practitioners who feel responsibilities in this area of medicine. Close cooperation with anaesthesiologists seems mandatory to achieve and sustain a high-quality standard for our patients undergoing medical or surgical procedures under sedation.

Summary

The use of muscle relaxants, considered until recently as common practice in current neurosurgical anaesthesia protocols, becomes increasingly more questionable today. The reasons rely on the evolution of neurosurgery including the advent of new surgical techniques, the evolution of anaesthesia having the benefit of new drugs and devices, and the rationale for using muscle relaxants balanced against their potential side-effects and possible pharmacodynamic alterations in neurosurgical patients.

The dose-related effects of milrinone, a phosphodiesterase (PDE) III inhibitor, on the contractility of fatigued diaphragm were studied in dogs. Animals were divided into three groups of eight each. Diaphragmatic fatigue was induced by intermittent supramaximal bilateral electrophrenic stimulation at a frequency of 20 Hz applied for 30 min. After the production of fatigue, Group I received no study drug; Group II was infused with milrinone (50 mg kg−1 loading dose plus 0.2 mg kg−1 min−1 maintenance dose); Group III was infused with milrinone (50 mg kg−1 loading dose plus 0.5 mg kg−1 min−1 maintenance dose). Diaphragmatic contractility was assessed by measurement of transdiaphragmatic pressure. After the fatigue-producing period, transdiaphragmatic pressure at low-frequency stimulation (20-Hz) decreased from the prefatigued values in all groups (P < 0.05), whereas transdiaphragmatic pressure at high-frequency (100-Hz) stimulation did not change. Compared with Group I, transdiaphragmatic pressure to each stimulus increased during milrinone infusion in Groups II and III (P < 0.05). The increase in transdiaphragmatic pressure was greater in Group III than in Group II (P < 0.05). It is concluded that milrinone is associated with a dose-related effect on the contractility of fatigued diaphragm in dogs.

Summary

Background and objective: Headache is a common and distressing morbidity associated with day case surgery. We undertook a prospective, observational study to identify risk factors associated with perioperative headache in a modern, day case surgery setting.

Methods: Two hundred-and-thirty consecutive patients presenting for day case surgery were invited to complete a questionnaire about their previous experience of headache and various associated risk factors. Questionnaires were completed by 90% of patients. The presence of headache in the pre- or postoperative period was also documented. We used multivariate logistic regression to model perioperative headache.

Results: Increased frequency of previous headache, odds ratio (95% confidence interval) 1.9 (1.2–2.8) (P = 0.004) and low alcohol consumption 0.90 (0.87–0.98) (P = 0.019) were significant predictors. A history of migraine showed a trend towards being predictive 1.9 (0.9–4.0) (P = 0.055). Some risk factors thought to be important such as caffeine withdrawal and duration of starvation and fluid deprivation were not associated with perioperative headache in this setting.

Conclusions: In this study of risk factors associated with perioperative headache in day case surgery, increased frequency of headache and low alcohol consumption were independent risk factors.

Background and objective: A critical factor that delays patient discharge following day-surgery is severe postoperative pain and the requirement for strong analgesics. Laparoscopic sterilization is a day case procedure and is associated with additional postoperative pain compared with diagnostic laparoscopy. This pain, associated with application of Filshie clips, may be ischaemic or spasmodic in aetiology. Papaverine relaxes smooth muscle, and the aim of the study was to investigate if papaverine would be effective in improving postoperative pain if administered directly to the Fallopian tubes. Bupivacaine is used commonly in day-surgery and so we compared the effect of this local anaesthetic with saline placebo.

Methods: Sixty-six ASA I-II females undergoing laparoscopic sterilization were entered into the prospective, randomized, double-blind, placebo-controlled clinical trial. They received intrauterine papaverine (30 mg) or bupivacaine (0.375% 30 mL) or normal saline (30 mL) via the transcervical route before application of Filshie clips.

Results: There were no significant differences in the postoperative period between the three groups in the number of patients needing analgesia in the first 60 min postoperatively, the time to first analgesia, the rescue analgesic or antiemetic consumption, the incidence of postoperative nausea and vomiting, and the sedation and visual analogue pain scores.

Conclusions: From the data presented, we would not recommend routine transcervical administration of papaverine or bupivacaine for pain following laparoscopic sterilization.

The acute influence of therapeutic doses of theophylline on cerebral blood flow velocities during general anaesthesia induced either by halothane or isoflurane has not been elucidated previously. The aim of this study, was therefore to investigate these effects during steady state anaesthetic conditions in anaesthetized patients using transcranial Doppler sonography. Thirty-four Patients were investigated. Anaesthesia was maintained either with 1 MAC (minimum alveolar concentration) halothane (n=16) or 1 MAC isoflurane (n=18); FiO2: 40%; end-expiratory pCO2: normocapnia. Theophylline administration was performed before surgery by infusing 6 mg kg−1 over a period of 7.5 min. Measurements were recorded prior to theophylline administration, and immediately after 2 mg kg−1 (2.5 min), 4 mg kg−1 (5 min) and 6 mg kg−1 (7.5 min), as well as 5, 10, 15, 20, 30 and 45 min after theophylline administration. Recorded variables included blood pressure, heart rate, arterial oxygen saturation, end-expiratory pCO2, body temperatures, middle cerebral artery blood flow velocity and pulsatility index. Theophylline administration was well tolerated by all study subjects. Heart rate, blood pressure, body temperatures, arterial oxygen saturation and end-expiratory pCO2 remained constant during the whole examination period. Following theophylline, mean blood flow velocity decreased by 25% in the halothane and by 30% in the isoflurane group (P< 0.05). By the end of the examination period, mean blood flow velocity had not yet recovered to the initial values whereby in both groups the mean blood flow velocity was 26% below the initial values. In the isoflurane group, the pulsatility index increased by about 20% (P< 0.05) and remained high until the end of the examination. In the halothane group, however, there were no changes in the pulsatility index. Our results show a remarkable, significant and simultaneous decrease in blood flow velocity in the middle cerebral artery associated with theophylline administration during halothane and isoflurane anaesthesia in man.

Summary

Background and objective: Automatic tube compensation has been designed as a new ventilatory mode to compensate for the non-linear resistance of the endotracheal tube. The study investigated the effects of automatic tube compensation compared with breathing through a T-piece or pressure support during a trial of spontaneous breathing used for weaning patients from mechanical ventilation of the lungs.

Methods: Twelve patients were studied who were ready for weaning after prolonged mechanical ventilation (10.2 ± 8.4 days) due to acute respiratory failure. Patients with chronic obstructive pulmonary disease were excluded. Thirty minutes of automatic tube compensation were compared with 30 min periods of 7 cmH2O pressure support and T-piece breathing. Breathing patterns and workload indices were measured at the end of each study period.

Results: During T-piece breathing, the peak inspiratory flow rate (0.65 ± 0.20 L s−1) and minute ventilation (8.9 ± 2.7 L min−1) were lower than during either pressure support (peak inspiratory flow rate 0.81 ± 0.25 L s−1; minute ventilation 10.2 ± 2.3 L min−1, respectively) or automatic tube compensation (peak inspiratory flow rate 0.75 ± 0.26 L s−1; minute ventilation 10.8 ± 2.7 L min−1). The pressure–time product as well as patients' work of breathing were comparable during automatic tube compensation (pressure–time product 214.5 ± 104.6 cmH2O s−1 min−1, patient work of breathing 1.1 ± 0.4 J L−1) and T-piece breathing (pressure–time product 208.3 ± 121.6 cmH2O s−1 min−1, patient work of breathing 1.1 ± 0.4 J L−1), whereas pressure support resulted in a significant decrease in workload indices (pressure–time product 121.2 ± 64.1 cmH2O s−1 min−1, patient work of breathing 0.7 ± 0.4 J L−1).

Conclusions: In weaning from mechanical lung ventilation, patients' work of breathing during spontaneous breathing trials is clearly reduced by the application of pressure support 7 cmH2O, whereas the workload during automatic tube compensation corresponded closely to the values during trials of breathing through a T-piece.

Summary

Background and objective: Intrathecal injections of the benzodiazepine midazolam have been reported to cause antinociception in animals and pain relief in human beings, including the potentiation of opioid analgesia. This study compared the efficacy of the addition of midazolam to a mixture of buprenorphine and bupivacaine used for spinal anaesthesia.

Methods: The study was prospective, randomized, and observer blinded. It involved 60 patients (30 per group), ASA I and II, age 20–40 yr, undergoing minor and intermediate lower abdominal surgery under spinal anaesthesia. Patients were randomized into two groups: the control group received a spinal injection of hyperbaric bupivacaine (15 mg) plus buprenorphine (0.15 mg) and the experimental group received a spinal injection of the same two drugs and doses but supplemented with intrathecal midazolam (2 mg).

Results: The duration of postoperative analgesia in the control group was 9.24 ± 2.57 h (mean ± SEM), and 21.33 ± 12.69 h in the midazolam treated group (P < 0.001). Patients treated with intrathecal midazolam had better pain relief judged by visual analogue score on coughing (P = 0.0013) and a nursing mobility score (P < 0.0001). Adverse effects were minor and their incidence was similar in both groups.

Conclusions: We conclude that intrathecal midazolam 2 mg improves the quality and duration of postoperative pain relief afforded by intrathecal buprenorphine and bupivacaine.

Summary

Background and objective: In a retrospective study, we examined the suitability of a departmental clinical protocol for anaesthesia induction with target-controlled infusion of propofol developed for fibreoptic intubation in spontaneously breathing patients scheduled for outpatient oral surgery at the dental clinic of the Vienna University Hospital.

Methods: Propofol was administered using target-controlled infusion (Diprifusor®) at increasing target plasma concentrations starting at 2.5 μg mL−1. After 10 min, an intravenous dose of alfentanil (5–10 μg kg−1) was given for pain reduction. After a further 2 min, the patient was evaluated for response to auditory stimulation. If unresponsive, fibreoptic intubation was performed, otherwise the target concentration was increased by 0.2 μg mL−1 every 2 min until non-responsiveness was attained.

Results: Tracheal intubation was successful in all patients without any haemodynamic instability. However, one patient required facemask ventilation for 2 min. No patient was aware of intubation. The plasma concentration required for non-responsiveness was 2.8 ± 0.4 μg mL−1 (mean ± SD).

Conclusions: When using a target-controlled infusion of propofol, fibreoptic intubation can be performed with complete amnesia of the procedure for the patient. However, assisted ventilation of the lungs may be necessary as spontaneous ventilation may cease.

Summary

Background and objectives: Salt-water aspiration results in pulmonary oedema and hypoxia. We tested the hypothesis that partial liquid ventilation has beneficial effects on gas exchange and rate of survival in acute and extended salt water-induced lung injury. Methods: Anaesthetized, ventilated rats (tidal volume 6 mL kg−1, PEEP 5 cmH2O) received a tracheal salt-water instillation (3%, 8 mL kg−1 body weight) and were randomly assigned to three groups (n = 10 per group). While lungs of Group 1 were gas-ventilated, lungs of Group 2 received a single perfluorocarbon instillation (30 min after the injury, 5 mL kg−1 perfluorocarbon) and lungs of Group 3 received an additional continuous perfluorocarbon application into the treachea (5 mL kg−1 h−1). Arterial blood gases were measured with an intravascular blood gas sensor. Results: Salt-water instillation resulted in a marked decrease in PaO2 values within 30 min (from 432 ± 65 to 83 ± 40 mmHg, FiO2 = 1.0, P < 0.01). Arterial oxygenation improved in all three groups irrespective of treatment. We observed no significant differences between groups in peak PaO2 and PaCO2 values. Conclusions: Our results suggest that partial liquid ventilation has no additional beneficial effects on gas exchange after life-threatening salt water-induced lung injury when compared to conventional gas ventilation with positive end-expiratory pressure.