Background and objective: Comparison of the effectiveness of tramadol with meperidine given intravenously to emergency patients with suspected renal colic.

Methods: A double-blind, randomized clinical trial was performed in the Emergency Department of a tertiary-care university hospital. Consecutive patients with suspected renal colic (n =47) were randomized to receive intravenously an initial dose of tramadol 50 mg (n = 23) or meperidine 50 mg (n = 24). After 30 min, additional doses of meperidine 50 mg were given intravenously as a rescue medication in an open fashion. Pain relief was assessed using a 10 cm visual analogue scale, the primary outcomes being pain relief at 15 and 30 min after the analgesics. Secondary outcomes were the frequency of rescue meperidine use and the development of side-effects.

Results: Visual analogue scale pain scores after 15 and 30 min decreased in both tramadol and meperidine groups (P < 0.05). However, pain relief was better in the meperidine group at the 15 and 30 min evaluations (P < 0.05). Only 11 patients (48%), initially receiving meperidine, needed more meperidine compared with 16 patients (67%) initially receiving tramadol. Both drugs were well tolerated with no adverse effects occurring in either group.

Conclusions: Meperidine 50 mg was superior to tramadol 50 mg for acute pain relief in patients with suspected renal colic when given intravenously. Because many patients in both groups received supplemental meperidine and the response to tramadol alone cannot be predicted, clinicians may want to choose higher doses of meperidine alone or other alternative combinations.

Monocytes play a very important part in humoral as well as in cell-mediated immunity. At present, however, the knowledge of the influence of anaesthetic agents on the functions of monocytes is limited. In the present study, the effects of thiopentone, methohexitone, ketamine, midazolam, droperidol, propofol, etomidate, and fentanyl on monocyte chemotaxis were examined in vitro using a 48-well microchemotaxis chamber. Clinically relevant concentrations of ketamine, midazolam, and droperidol significantly (P≤0.05) inhibited chemotaxis. For that reason, it is possible that these anaesthetics impair the immunological system in vivo. This possibility should be further examined.

Summary

Background and objective: Inaccurate measurements of body temperature following cardiopulmonary bypass may be associated with serious complications. The purpose of this study was to determine whether axillary and tympanic temperature measurements correlate with the urinary bladder temperature in the early postcardiac surgery period. Methods: Forty-nine adult patients who underwent cardiac surgery under cardiopulmonary bypass at our institution were prospectively studied. Urinary bladder, right axillary, right tympanic and left tympanic temperature measurements were simultaneously recorded at 0, 6, 12 and 18 h following cardiopulmonary bypass. Patients had one to four sets of recordings and a total of 629 temperature measurements were recorded. The mean difference (bias) between the bladder and each of the other methods and limits of agreement were calculated using Bland and Altman method. Results: The mean core body temperature recorded from the bladder on admission to the intensive care unit was 36.4°C. After 6, 12 and 18 h the mean core body temperature was 37.4°C (range: 35.2–39.0), 37.5°C and 37.45°C, respectively. The mean differences (bias) between the bladder temperature and the other three methods were: left tympanic, 0.65°C (95% CI: −0.24 to 1.58); right tympanic, 0.57°C (95% CI: −0.48 to 1.63) and right axillary, 0.55°C (95% CI: −0.27 to 1.36). Conclusions: The axilla and tympanic membrane are unreliable sites for core body temperature measurement early after cardiopulmonary bypass in adult patients and clinical decisions should be based on more reliable methods.

Summary

Background and objective: A randomized double-blind controlled trial was performed to determine if there was a difference in discomfort on injection between two preparations of propofol. A long-chain triglyceride preparation (LCT-propofol (Fresenius)) was compared against a medium- and long-chain triglyceride preparation (MCT/LCT-propofol (BBraun)). Methods: One hundred and twenty ASA I–II patients listed for elective procedures were consented and randomized to receive either induction agent. A standard rate of infusion was used for induction of anaesthesia and subjects were questioned about discomfort until contact was lost. Discomfort was recorded as none, mild, moderate or severe. Incidence of postoperative nausea and vomiting and anti-emetic requirements were recorded in the postanaesthetic care unit. Results: There was seen to be a 54% reduction in moderate/severe discomfort with MCT/LCT-propofol compared with LCT-propofol (P < 0.006). There was a 70% reduction in severe discomfort with MCT/LCT-propofol compared with LCT-propofol (P < 0.04). The term discomfort was used during the study because there is a wide array of unpleasant sensations felt by patients during propofol induction which are not always reported as pain. There was no significant difference in the incidence of postoperative nausea and vomiting or anti-emetic use between the two groups. Conclusions: There is a significant decrease in the incidence of discomfort with MCT/LCT-propofol compared with LCT-propofol. This difference is more marked in subjects reporting severe discomfort.

The mission of the Section and Board of Anaesthesiology of the European Union of Medical Specialists (EUMS/UEMS) is to harmonize training and medical practice in all European countries to continuously improve the quality of care. The need for continuous medical education in the field of anaesthesiology has long been recognized. However, specialty-based competencies are not the only requirements for successful medical practice. The need to acquire medical, managerial, ethical, social and personal communication skills on top of specialty-based competencies has developed into the principle of continuous professional development, which embraces both objectives. The Section and Board of Anaesthesiology of the EUMS/UEMS has approved a proposal of its Standing Committee on Continuous Medical Education/Continuous Professional Development to adopt the following charter on the subject.

Summary

Background and objectives: Infraclavicular plexus block has many advantages of particular interest in the emergency setting. However, the number of nerve stimulations needed to optimize the technique remains unclear. We evaluated both the local anaesthetic requirement and the success rate of Sim's derived infraclavicular plexus block performed with a nerve stimulator when either one or two responses were sought. Methods: In this prospective study, 50 patients who presented for distal upper limb surgery were randomized into two groups: in Group 1, ropivacaine 0.75% 40 mL was injected when nerve stimulation elicited a distal motor response (median, ulnar or radial). In Group 2, only 30 mL of the same local anaesthetic was injected, 7 mL to the musculocutaneous nerve and 23 mL to the median, ulnar or radial nerves. Sensory and motor blocks were tested at 5-min intervals over 30 min. Results: The time to perform the block was similar in both groups. The success rate of the block increased from 80% in the single-stimulation group to 92% in the double-stimulation group (not significant). The onset time of sensory and motor block was shorter and block extension was greater in ulnar, antebrachial cutaneous and brachial cutaneous nerve distributions in the multistimulation group (P < 0.05). Conclusions: We conclude that only 30 mL of local anaesthetic seems to be sufficient to ensure a high level of success when performing an infraclavicular block with stimulation of both the musculocutaneous nerve and median, ulnar or radial nerve.

Summary

Background and objective: The aim of this prospective, randomized, double-blind study was to determine the effects of adding nitrous oxide on sevoflurane requirement for blunting sympathetic responses after surgical incision combined with two different target-controlled concentrations of remifentanil (1 and 3 ng mL−1) in female.

Methods: 102 female patients, aged 20–50 yr, ASA I, undergoing general anaesthesia for elective abdominal surgery were enrolled and randomly allocated to receive sevoflurane anaesthesia alone (Group A, n = 53), or with the addition of 60% nitrous oxide (Group N, n = 49). Patients of both groups were further assigned to receive a target-controlled remifentanil infusion with an effect-site concentration of either 1 ng mL−1 (Group N1, n = 27; Group A1, n = 30), or 3 ng mL−1 (Group N3, n = 22; Group A3, n = 23). Sympathetic responses to surgical incision were determined after a 20-min period of stable end-tidal sevoflurane and target-controlled remifentanil concentrations. Predetermined end-tidal sevoflurane concentrations and minimum alveolar concentration (MAC) for each group were determined using an up-and-down sequential allocation technique.

Results: The MAC of sevoflurane was 3.96% (95% confidence interval, CI95: 3.69–4.23%) in Group A1 and 1.2% (CI95: 0.9–1.3%) in Group N1 (P < 0.01), while in Groups A3 and N3 the MAC of sevoflurane was 0.36% (CI95: 0.24–0.47%) and 0.18% (CI95: 0.1–0.3%), respectively (P < 0.05).

Conclusion: Adding 60% nitrous oxide reduces the MAC of sevoflurane by 70% when using a remifentanil concentration of 1 ng mL−1 and 50% when using a remifentanil concentration of 3 ng mL−1.

Application of high-silica zeolites in a special adsorber anallows complete selective adsorption of the inhalation anaesthetic desflurane from the outlet port of the scavenging system of the anaesthesia machine. In comparison with charcoal filters, zeolites allow almost complete desorption at moderate temperatures followed by condensation of the desflurane to the liquid phase. The adsorption of scavenged desflurane by zeolites was measured in 13 patients. The duration of the anaesthesia was between 70 and 130 min. A minimal-flow regime (0.5 L min−1 fresh gas inflow) was used for maintenance in seven patients and a higher-flow regime (3 L min−1 fresh gas flow) was used for maintenance in six patients. In minimal-flow anaesthesia, 62% of the delivered desflurane was adsorbed by the zeolite while 86% of the delivered desflurane was adsorbed in higher-flow anaesthesia. Preliminary results show that about 85% of the adsorbed desflurane could be recovered as liquid with high purity via desorption.

Recent studies have demonstrated that bedside cranial burr hole and insertion of intraparenchymal catheters for intracranial pressure monitoring performed by intensive care physicians is a safe procedure, with a complication rate comparable to other series published by neurosurgeons. The overall morbidity rate is comparable to, or even lower than, that caused by central vein catheterization. The procedure is also quite simple and modern disposable intracranial procedural kits are available. After the skin is prepped the landmark for skin incision, called the ‘Kocher’s point’, located about 2–4 cm lateral to the midline (mid-pupillary line) and 2–3 cm anterior to the coronal suture, is found. Then the surgical field is prepared with the sterile drapes and the skin infiltrated with local anaesthetic (0.5% lidocaine with 1 : 200 000 epinephrine). After skin incision and retraction of the skin and subcutaneous tissue, the periosteum should be scraped off in order expose the skull. The skin is then divaricated, exposing the underlying bone. The hole is drilled with either an electric drill or a twist drill (the drilling procedure must be performed with the drill held within 10° of the perpendicular position to the incision site). The hole is then irrigated with sterile saline and an 18-G spinal needle may be used to open the dura (exercise caution when perforating the dura so as to avoid damage to the underlying structures). Following opening of the dura, the Bolt, containing a stylet, is screwed manually into the skull at approximately 5 mm to 1 cm for adults. The stylet is then removed after the bolt has been screwed in, after which the bolt should be filled with saline. Finally, the zeroing of the transducer is performed by simply holding the tip in air while zeroing on the monitor. The transducer is inserted inside the bolt and the screw tightened. The intracranial pressure value can then be read.

The authors compared the acceptance and efficacy of rectal and nasal administration of midazolam (MDZ) for premedication. Ninety-five ASA I and II paediatric patients (8 months to 12 years) scheduled for elective surgery were randomly allocated to two groups. Group R received 0.3 mg kg−1 of rectal midazolam (in 5mL saline). Group N received 0.2 mg kg−1 of nasal midazolam (5 mg ml−1). Both groups were divided in two subgroups according to age (group RA ( ≤ 6 years, n = 33), group RB ( > 6 years, n = 18), group NA ( ≤ 6 years, n = 28), group NB ( > 6 years, n = 16)). At the time of premedication, tolerance to the administration was confirmed. Twenty min after rectal or 10 min after nasal administration the quality of sedation was recorded. The nasal midazolam, in commonly used dosages, induced a sedation similar to that following rectal administration with a shorter delay of onset. Nasal administration was more often painful than rectal administration. Swallowing (nasal midazolam) and concerns about modesty (rectal midazolam) were more frequent in older children. Because of its poor tolerance, nasal premedication should be reversed for cases where there is no alternative. Rectal premedication should be avoided in older children.

Masseter muscle rigidity after suxamethonium, usually occurring in children induced with halothane,is associated with malignant hyperthermia. A case is reported in which masseter muscle rigidity occurred in an adult following vecuronium. From the limited data available, this and two similar reported cases, it appears that non-depolarizing muscle relaxants can, very rarely, cause masseter muscle rigidity in adults. This masseter muscle rigidity may complicate airway management, but is unlikely to progress to generalized rigidity and malignant hyperthermia.

Summary

Background and objective: Volatile anaesthetics depress excitatory signal transmission by potentiating the inhibitory action of GABAA receptors and there is strong evidence that this is related with anaesthesia. Using primary hippocampal cultures we analyzed the possibility that the volatile anaesthetics enflurane and sevoflurane depress excitatory signal transmission by activation of adenosine A1 receptors. Methods: Primary rat hippocampal cultures on 4 cm poly-l-lysine coated glass coverslips were loaded with the Ca2+-indicator fluo-3 and incorporated in a gastight, temperature-controlled perfusion chamber. The intracellular Ca2+-concentration was monitored with a confocal laser-scanning microscope (BioRad) using the 488 nm laser line of a krypton–argon laser for excitation and the Lasersharp Acquisition software for analysis. Results: Continuous perfusion in Mg2+-free medium generated spontaneous synchronized calcium oscillations, which were dose dependently depressed by the volatile anaesthetics enflurane and sevoflurane (0.25–1 minimum alveolar concentration). Addition of 100 nmol of 2-chloro-N6-cyclopentyladenosine, a specific adenosine A1 receptor antagonist, partly reversed the anaesthetic-induced inhibition of the oscillation amplitude of the oscillating cells. The effect of the anaesthetics was mimicked by the addition of S-(p-nitrobenzyl)-6-thioguanosine, an adenosine transport inhibitor and by the addition of 5-amino-5-deoxyadenosine, an inhibitor of adenosine kinase. Conclusions: The volatile anaesthetics sevoflurane and enflurane activate adenosine A1 receptors in primary rat hippocampal cultures. This effect is mediated by liberation of adenosine most likely by an interaction of the volatile anaesthetics with adenosine transport or key enzymes in adenosine metabolism.

The anti-emetic efficacy of prophylactic ondansetron and tropisetron in combination with a low dose of droperidol in patients with high probability for post-operative nausea and vomiting undergoing gynaecological laparoscopy was compared. Patients were randomly allocated in a double-blind manner to receive either ondansetron 8 mg (n=45) or tropisetron 5 mg (n=43) at the end of surgery. A standardized general anaesthetic technique was used, including droperidol 0.75 mg. The incidence of nausea was 36% and 49% (P=0.28), and vomiting occurred in 13% and 14% of the patients in the ondansetron and tropisetron groups, respectively. The onset time for rescue medication was significantly sooner after tropisetron than ondansetron (3 h 18min vs. 6 h 25min; P=0.007). There were no statistically significant differences in efficacy between prophylactic ondansetron and tropisetron combined with droperidol in a high-risk population. However, ondansetron appeared to be more effective in preventing post-operative nausea and vomiting in the early hours after surgery compared with tropisetron.

Background and objective: The effects of remifentanil, alfentanil and fentanyl were compared on cardiovascular responses to laryngoscopy and endotracheal intubation in morbidly obese patients.

Methods: Eighty morbidly obese ASA I–II patients were included in the study. Patients were randomly divided into four groups to receive either 1 μg kg−1 fentanyl (Group F), 10 μg kg−1 alfentanil (A), 1 μg kg−1 followed by an infusion of 0.5 µg kg min−1 remifentanil (R) or saline (P). The patients corrected weight was used to calculate the drug doses. Body mass indices (range) were: 54.3 ± 7.37 (49–78.4), 55.67 ± 7.44 (48.5–78.4), 53.17 ± 5.36 (48.1–63.2), and 56.3 ± 6.09 (46.6–67.7) kg m−2, in Groups F, R, A and P respectively. Systolic, diastolic and mean arterial pressures and heart rate were measured non-invasively at three time points, which were 2 min before induction, 2 min after induction and 2 min after endotracheal intubation.

Results: After induction of anaesthesia, arterial pressures decreased significantly in all groups, but the decrease was more pronounced in Groups A and R. After induction, heart rate decreased significantly in all groups except in Group P. After intubation, haemodynamic responses were similar in the remifentanil, fentanyl and alfentanil groups and were within normal limits. In Group P, arterial pressures and heart rates were significantly higher.

Conclusions: Alfentanil, fentanyl and remifentanil in the doses described had similar effects in controlling the haemodynamic response to tracheal intubation in ASA I–II morbidly obese patients.