Summary

Background and objective: Non-steroidal anti-inflammatory drugs are considered as an effective treatment of postoperative pain after laparoscopic cholecystectomy. COX-2 inhibitors are newer drugs having less adverse effects. Data supporting their efficacy postoperatively in comparison to older non-steroidal anti-inflammatory drugs are scarce. Our study is a prospective, randomized, double-blinded, placebo-controlled trial comparing the efficacy of lornoxicam vs. parecoxib for the management of pain after laparoscopic cholecystectomy. Materials and methods: We enrolled 76 patients, ASA I and II, scheduled for elective laparoscopic cholecystectomy. The patients were randomized to receive before induction parecoxib 40 mg i.v., lornoxicam 8 mg i.v. or placebo. Pain at rest and on movement was assessed using a visual analogue scale at 0, 6, 12 h postoperatively. Total meperidine consumption and adverse effects were also recorded. Results: At 12 h, visual analogue scale scores at rest and on movement were significantly lower with parecoxib and lornoxicam compared with control ( P = 0.047). The percentage of patients needing meperidine and the average dose of meperidine administered was significantly lower with parecoxib and lornoxicam compared with control (P < 0.001 and P = 0.018). There was no difference between parecoxib and lornoxicam. One patient receiving lornoxicam vomited. Conclusions: Parecoxib 40 mg i.v. and lornoxicam 8 mg i.v. were equianalgesic and both were more efficacious than placebo for the management of pain after laparoscopic cholecystectomy.

Background and objective The laryngeal tube is a variant of the oesophageal obturator airway. The manufacturer claims that it is an alternative to ventilation with a facemask, laryngeal mask or endotracheal tube. To date, published studies have only involved controlled ventilation. We wished to find out if its use in spontaneous ventilation was equivalent to using the laryngeal mask airway.

Methods We have compared the laryngeal tube with the laryngeal mask in a randomized prospective study involving patients breathing spontaneously under general anaesthesia. Criteria and a scoring system were used for the comparison. A sequential analysis chart with P=0.01 was chosen for each of two anaesthetists.

Results Only seven and 10 pairs of patients were required to indicate that the laryngeal tube was poorer at airway maintenance than the laryngeal mask. Of the 17 patients who had received the laryngeal tube, successful airway maintenance was only possible in seven. In the remaining 10 patients, the laryngeal tube was abandoned and the rescue airway was the laryngeal mask in all cases. All 17 patients randomized to the laryngeal mask were successfully managed.

Conclusions We conclude that the laryngeal tube is not a satisfactory device for management of the airway during spontaneous ventilation.

Recently, it was suggested that peripherally-mediated analgesia can be accomplished by the intra-articular delivery of the mu-opioid morphine or of the a2-agonist clonidine. This clinical study assesses the potential peripheral analgesic effect of the combination of morphine and clonidine after intra-articular administration. Sixty patients (American Society of Anesthesiologists status I or II) undergoing arthroscopic repair of the knee during general anaesthesia were randomized to receive after operation, in a double-blind manner, either 1 μg morphine intra-articularly (group 1); 150 μg clonidine intra-articularly (group 2); or 1 μg morphine + 150 μg clonidine intra-articularly (group 3); or normal saline intra-articularly (group 4) in a volume of 30 mL, respectively. Visual analogue pain scores (VAS), duration of analgesia as defined by first demand for supplemental analgesics, subsequent 24 h consumption of postoperative supplementary supplementary analgesics, and patient satisfaction were evaluated. Co-administration of morphine + clonidine (group 3) resulted in a significant VAS reduction at 2 h after injection compared with the other groups. There was a tendency towards a lower need for supplementary rescue analgesia and towards a more prolonged analgesia in group 3 (211 min ± 224 min SD) compared with group 1 (173 min ± 197 min SD) and group 4 (91 min ± 21 min SD). More patients were very satisfied with the postoperative analgesic regimen receiving the combination of morphine and clonidine (group 3) at 24 h postoperatively. Thus we conclude, that the peripheral co-delivery of an opioid and an a2-agonist will result in improved postoperative pain relief, when compared with each single agent given alone.

Background and objective Transoesophageal echocardiography is increasingly used for evaluation and monitoring of left ventricular function in anaesthetized patients. However, the only available reference values for transoesophageal echocardiography were derived from studies in awake subjects.

Methods We determined left ventricular dimensions and systolic function in 45 patients without clinical evidence of heart disease who voluntarily underwent transesophageal echocardiography under conditions of balanced general anaesthesia, controlled fluid administration, supine position, muscle relaxation and controlled ventilation.

Results The left ventricular dimensions obtained during these conditions were lower than the published normal values in awake subjects. The indices of global left ventricular function, however, were similar to the normal values obtained by either awake transesophageal echocardiography or transthoracic echocardiography.

Conclusion We propose using the values obtained in our study as reference values for evaluation of left ventricular function in patients under general anaesthesia and controlled ventilation.

In an attempt to overcome infections associated with central venous catheters, a new antiseptic central venous catheter coated with benzalkonium chloride on the internal and external surfaces has been developed and evaluated in a clinical trial. Patients (235) randomly received either a triple-lumen central venous catheter coated with benzalkonium chloride (117) or a polyurethane non-antiseptic catheter (118). The incidence of microbial colonization of both catheters and retained antiseptic activity of the benzalkonium chloride device following removal were determined. The benzalkonium chloride resulted in a significant reduction of the incidence of microbial colonization on both the internal and external catheter surfaces. The reduction in colonization was detected at both the intradermal (21 benzalkonium chloride catheters vs. 38 controls, P=0.0016) and distal segments of the antiseptic-coated catheters. Following catheter removal retained activity was demonstrated in benzalkonium chloride catheters which had been in place for up to 12 days. No patients developed adverse reactions to the benzalkonium chloride catheters. The findings demonstrate that the benzalkonium chloride catheter significantly reduced the incidence of catheter-associated colonization.

Summary

Background and objective: In the perivascular sheath of the brachial plexus, the volume of anaesthetic solution determines the quality of anaesthetic cover. Fibrous septa may divide the perivascular space into compartments, leading to inadequate diffusion of the anaesthetic solution. The aim of our study was to obtain good anaesthesia and less complications using high volume of low concentration anaesthetic solution, overcoming the obstacle of the septa with a double approach to the scalene sheath. Methods: Sixty patients scheduled for shoulder capsuloplasty received both Winnie interscalene brachial plexus block and Pippa proximal cranial needle approach. The patients were randomly assigned to two groups. A constant dose of local anaesthetic was administered to each group: Group I (30 patients) received high volume (60 mL of anaesthetic solution) and Group II (30 patients) received low volume of solution (30 mL of anaesthetic solution). Sensory and motor block in the upper limb and complications were evaluated. Results: In all the patients the quality of anaesthesia obtained at the surgical site was excellent. In Group I also the areas supplied by the medial cutaneous nerves of the arm and forearm, ulnar, median and radial nerves were blocked (P < 0.002). Complications were only observed in Group II and consisted of bradycardia and hypotension (66% of the patients) and phrenic nerve paresis (27% of the patients). Conclusions: The lower concentration of the anaesthetic solution avoids complications while increased volume provides good analgesic cover. The combination of the Winnie interscalene plexus block and the Pippa proximal cranial needle approach should contribute to fill up the scalene sheath overcoming the septa obstacles.

Summary

Background and objective: A randomized, blind study to evaluate the effects on β-endorphin and substance P release after washing acid burns with 0.9% saline, calcium gluconate or diphoterine in a model of chemical burn in rats.

Methods: Twenty Sprague–Dawley rats (approximate weight 250 g) were anaesthetized with ketamine (30 mg kg−1 intramuscularly) and then given an acid injury on the back skin with 0.5 mL of hydrochloric acid 52%. The rats were then randomly allocated to receive no washing (control group, n = 5), washing with normal saline (0.9% NaCl) (n = 5), 10% calcium gluconate (n = 5) or diphoterine (n = 5). Blood concentrations of substance P and β-endorphin were measured 6 h, 48 h and 7 days after the chemical burn. An independent blinded observer evaluated wound healing at the 7th day.

Results: Seven days after burn wound healing was almost complete only in rats treated with diphoterine. Plasma concentrations of substance P were lower in rats receiving skin flushing with diphoterine compared to the other groups at 6 and 48 h after acid burn (P < 0.05 and P < 0.05, respectively); this was also associated with higher concentrations of β-endorphin at day 7 (P < 0.05).

Conclusions: Skin flushing with diphoterine reduced substance P release during the first 48 h after burn, and was associated with better wound healing and higher concentrations of β-endorphin 7 days later when compared with normal saline or 10% calcium gluconate.

This study evaluates the prophylactic anti-emetic efficacy of granisetron, droperidol and metoclopramide, for the prevention of post-operative nausea and vomiting in female patients undergoing elective laparoscopic cholecystectomy. The patients were randomly assigned to one of four groups (n=30 for each group): granisetron 3 mg, droperidol 1.25 mg, metoclopramide 10 mg and placebo (saline). These medications were given immediately before the induction of anaesthesia. During the first 24 h after an-aesthesia, the incidence of post-operative nausea and vomiting was 13, 30, 33 and 37% after administration of granisetron, droperidol, metoclopramide and placebo, respectively (P>0.05, overall Fisher's exact probability test). No clinically important adverse effects were observed in either group. Our results suggest that granisetron is a better anti-emetic than droperidol or metoclopramide for the prevention of post-operative nausea and vomiting after laparoscopic cholecystectomy when compared with a placebo.

Summary

Background and objective: Low flow desflurane and sevoflurane anaesthesia were administered to children and compared for haemodynamic response, renal and hepatic function, recovery time and postoperative nausea and vomiting. Methods: Eighty ASA I–II patients aged 5–15 yr were included in the study. Midazolam was given for premedication. Anaesthesia induction was performed with fentanyl, propofol and atracurium. After intubation, the first group received desflurane, oxygen and nitrous oxide at 6 L min−1 and the second sevoflurane, oxygen and nitrous oxide at 6L min−1. Ten minutes after induction the flow was decreased to 1L min−1 in both groups. Haemodynamic parameters, preoperative and postoperative renal and hepatic function, the times of operation and anaesthesia, and early recovery data were recorded. Modified Aldrete scores were noted at the 10th and 30th minutes postoperatively and postoperative nausea, and vomiting were assessed. Results: There were no significant differences in haemodynamic parameters, renal and hepatic functions, postoperative recovery and postoperative nausea and vomiting between groups. The recovery time was shorter in the desflurane group compared to the sevoflurane group. Conclusion: Low flow desflurane and sevoflurane anaesthesia do not adversely affect haemodynamic parameters, hepatic and renal function in children. Desflurane may be preferred when early recovery from anaesthesia is warranted.

Summary

Background and objective: Emergency research (e.g. into cardiac arrest or head injury) needs to start immediately, often before the patient, or relative, can give consent. A recent European Directive will prevent or severely limit emergency research. Little is known about the public view of emergency research. Methods: Patients attending the outpatient department of a university teaching hospital were invited to complete a self-administered questionnaire. Research Ethics Committee approval was obtained and participants gave written informed consent. Results: Three hundred and five of 362 respondents (84%) thought emergency research should start in the absence of consent but should be obtained as soon as possible from the nearest relative (82%) or the patient (90%). If consent was refused 62% felt the data could still be used, as did 81% if the patient died. Despite 62% approving of public meetings to publicize emergency research only 35% would attend one. A previously recommended list of preconditions was endorsed: no other consentable group (47%); advance consent impossible (55%); unable to delay treatment (73%); consent to be obtained as soon as possible (88%); an adequately designed protocol (74%); Ethics Committee approval (71%); patient may benefit (85%); future patients may benefit (92%) and that the treatment was necessary and could not be delayed (91%). Conclusions: Emergency research must occur to improve the outcome from life-threatening illness or injury. The majority of people are aware of the importance of this research and that the normal rules of consent are not applicable. Alternative methods of recruitment need to be investigated.

Summary

Background: Changes in neutrophil and endothelial adhesion molecule expression occur during perioperative ischaemia and reperfusion (I/R) injury. We investigated the effects of lidocaine on neutrophil-independent changes in neutrophil and endothelial adhesion molecule expression associated with tourniquet-induced I/R.

Methods: Plasma was obtained from venous blood samples (tourniquet arm) taken before (baseline), during, 15 min, 2 and 24 h following tourniquet release in seven patients undergoing elective upper limb surgery with tourniquet application. Isolated neutrophils from healthy volunteers (n = 7) were pretreated in the presence or absence of lidocaine (0.005, 0.05 and 0.5 mg mL−1) for 1 h, and then incubated with I/R plasma for 2 h. Human umbilical vein endothelial cells (HUVECs) were pretreated in the presence or absence of lidocaine (0.005, 0.05 and 0.5 mg mL−1) for 1 h, and then incubated with the plasma for 4 h. Adhesion molecule expression was estimated using flow cytometry. Data were analysed using ANOVA and post hoc Student–Newman–Keuls tests.

Results: I/R plasma (withdrawn 15 min following tourniquet release) increased isolated neutrophil CD11b (P = 0.03), CD18 (P = 0.01) and endothelial intercellular adhesion molecule-1 (ICAM-1) (P = 0.008) expression compared to baseline. CD11b, CD18 and ICAM-1 expression on lidocaine (0.005 mg mL−1) treated neutrophils was similar to control. CD11b (P < 0.001), CD18 (P = 0.03) and ICAM-1 (P = 0.002) expression on lidocaine (0.05 mg mL−1) treated neutrophils and HUVECs was less than that on controls.

Conclusion: Increased in vitro neutrophil and endothelial cell adhesion molecule expression on exposure to plasma obtained during the early reperfusion phase is diminished by lidocaine at greater than clinically relevant plasma concentrations.

Background and objective To test the hypothesis that magnesium sulphate reduces the amount of remifentanil needed for general anaesthesia in combination with propofol and mivacurium, we studied 50 patients undergoing elective pars plana vitrectomy in a double-blind, randomized prospective fashion.

Methods Magnesium sulphate (50 mg kg−1 body weight) or placebo (equal volume of NaCl) was given slowly intravenously after induction of anaesthesia with propofol 1–2 mg kg−1. Anaesthesia was maintained with propofol (using electroencephalographic control), mivacurium (according to train-of-four monitoring of neuromuscular blockade) and remifentanil (according to heart rate and arterial pressure).

Results We observed a significant reduction in remifentanil consumption from 0.14 to 0.09 μg kg−1> min–1 (P> < 0.01). Mivacurium consumption was also markedly reduced from 0.01 to 0.008 mg kg −1min−1 (P < 0.01), whereas propofol consumption remained unchanged. There was a trend towards lower postoperative pain scores, less pain medication requirements in 24 h after surgery and less postoperative nausea and vomiting in the magnesium group but not statistically significant. No side-effects were observed.

Conclusion We can recommend the use of magnesium sulphate as a safe and cost-effective supplement to a general anaesthetic regimen with propofol, remifentanil and mivacurium, although we cannot clearly distinguish between a mechanism as a (co)analgesic agent at the NMDA-receptor site or its properties as a sympatholytic. The effect of a single bolus dose of 50 mg kg−1 on induction lasts for about 2 h. For longer cases, either a continuous infusion or repeated bolus doses might be necessary.

The long QT syndrome is a disorder of myocardial electrical conduction that leaves the heart vulnerable to the ventricular tachydysrhythmia torsade de pointes. Clinically, this results in syncope or sudden death. The long QT syndrome may be congenital, if caused by abnormal myocardial potassium or sodium ion channels, or acquired, if due to drugs, electrolyte abnormalities or metabolic conditions. Triggers for the development of torsade de pointes include both anaesthesia and surgery. Some anaesthetic agents prolong the QT interval. The condition is reviewed and suggestions are made for the anaesthetic management of affected patients.