Environmental monitoring of anaesthetic gases was carried out in theatre areas in eight hospitals as well as in Delivery suites, radiology, radiotherapy and Dental suites. High staff exposures occurred in nontheatre areas although exposures in theatres were generally satisfactory. Environmental control measures are required where staff exposures exceed legal standards.

A small decrease in cerebral blood flow (approximately 10%) in response to 100% oxygen (O2) administration is well recognized. This observation was based on human volunteer studies, which employed a nitrous oxide washout method for the measurement of cerebral blood flow. Because this method is now appreciated to be subject to potential errors we have examined the cerebral blood flow response to 100% oxygen using a magnetic resonance imaging technique to quantify changes in carotid and basilar artery flow. The study, was performed in 12 normal male subjects aged 23–42 years. We report decreases in cerebral blood flow ranging from 9 to 31% with a mean value of over 20%. The decrease in cerebral blood flow was greater in seven young subjects (aged 23–26 years) with decreases in cerebral blood flow of 19.3–31.4% (mean 26.8%). In five older subjects (aged 32–42 years), decreases in CBF were smaller (mean 16.2%). The administration of 100% O2 was accompanied by a small decrease in end-tidal CO2 (3.7–7.1%), insufficient to explain the changes in cerebral blood flow. We conclude that the decrease in cerebral blood flow in response to O2 administration is greater than previously described and appears to be greater in young adults.

Dedicated nitric oxide equipped ventilators are now available commercially but are not yet common in clinical practice. With other ventilators, there is no standardized procedure for the administration or monitoring of nitric oxide. Wedescribe the use of nitric oxide in conjunction with a simple time–cycled, pressure regulated, flow generating ventilator attached to a model infant–sized lung. The measured nitric oxide concentrations were always less than calculated. Infusion site, minute ventilation and sampling port all affected nitric oxide concentration (P<0.05). Increasing minute ventilation lowered measured nitric oxide concentration exponentially. Mixing of gases improved when nitric oxide was infused closer to the ventilator. Acid contamination was found in water samples from humidifier, water trap and ventilator gas outlet. Acidification was reduced, without change in measured nitric oxide delivery, when infused prehumidifier. We recommend, when used as therapy, nitric oxide levels in inspired gases should always be measured.

This study compares prospectively the cardiovascular and catecholamine responses to central venous and pulmonary artery catheterization before and after induction of general anaesthesia. Twenty patients for elective coronary artery surgery were randomized into two groups. One group had central venous and pulmonary artery catheterization performed awake using local anaesthesia. The other group had these catheters inserted following induction of general anesthaesia. In all patients heart rate, arterial blood pressure, ST segment analysis and epinephrine and norepinephrine levels were measured prior to central venous cannulation and at 2-min intervals until placement of the lines was achieved. There were no statistically significant changes in any cardiovascular or catecholamine variable with time compared with the base–line measurements. There were no statistically significant differences in plasma catecholamine levels between the awake and the anaesthetized groups.

A retrospective survey was undertaken of 142 adults who had undergone cardiac surgery with cardiopulmonary bypass. According to the manufacturer's instructions for thromboelastography, patients were identified as showing evidence of fibrinolysis if after coming off bypass the Ly30 index was ≥7.5%. In the 20 fibrinolytic patients, fibrinolysis was readily corrected by tranexamic acid but these patients needed more colloid and more vasopressor support than the non-fibrinolytic patients. There were three deaths, all in the fibrinolytic patients. It is possible that fibrinolysis is a marker for onset of systemic inflammation syndrome. It is recommended that, until the association between fibrinolysis and worse outcome is investigated further, patients showing fibrinolysis early after cardiopulmonary bypass should not be discharged too soon from intensive care.

This study was designed to determine the efficacy of oral etilefrine in preventing hypotension induced by spinal anaesthesia. Forty patients, ASA grade I or II, aged 23–60 years, scheduled for orthopaedic surgery involving the lower extremity under spinal anaesthesia were studied. The patients were randomly allocated to one of two groups; the etilefrine group (n=20) received oral etilefrine 15mg (30 drops), 60 min before the subarachnoid lock, and the control group (,n=20) received no etilefrine. Patients were given 0.5% isobaric bupivacaine intrathecally. Hypotension was defined as a 30% decrease from base-line for systolic arterial pressure and mean arterial pressure or systolic value <90mmHg, and was treated with intravenous boluses of etilefrine 2 mg. The overall incidence of spinal anaesthesia induced hypotension was 25%, ranging from 20% in the etilefrine group to 30% in the control group. The fall in systolic arterial pressure and mean arterial pressure was significantly greater in the control group than in the etilefrine group (P < 0.05). The patients in the etilefrine group received less etilefrine supplement than those in control group and no subject in the etilefrine group required repeat etilefrine doses, while in the control group five patients received multiple etilefrine doses (P < 0.05). The mean heart rate remained fairly stable throughout the study periods. We conclude that oral etilefrine, given 60 min before surgery, reduces the fall in blood pressure during spinal anaesthesia.

Treatment of ingrowing toenail is commonly performed under local anaesthesia with a digital ring block. Ring block can be associated with significant pain, caused by needle insertion and deposition of the local anaesthetic agent. EMLA, a topical anaesthetic cream, is widely used to alleviate the pain of venepuncture. The aim of this study was to investigate whether the discomfort of digital block could be reduced by prior application of EMLA. Fifty–five patients who were scheduled for ingrowing toenail under local anaesthesia were randomized into two groups. In Group 1 (n = 30), EMLA was applied around the base of the affected hallux for at least 1 h before ring block. In Group 2 (n = 25), a placebo cream was used. In this double-blind study, patients assessed the pain caused by a standardized ring block using 100-mm visual analogue pain score. The mean visual analogue pain score in Group 1 was 28.1 and 50.1 in Group 2 (P<0.0001). We conclude that EMLA significantly reduces the pain associated with digital ring block.

In this prospective pilot study, nine patients suffering from complex regional pain syndrome of the arm were treated with morphine 0.16mg h−1 (3.84mg day−1) applied continuously through an axillary brachial plexus catheter. In all of them an oral analgesic medication including the less potent opioid tramadol had not provided sufficient pain relief. During regional treatment, patients were kept in hospital and physiotherapy was carried out frequently in order to improve strength and function of the affected arm. Pain at rest and during movement as well as grip strength were assessed at first visit, during morphine infusion and at a long–term follow–up visit. All assessments improved significantly during plexus analgesia. There were no major opioid related side–effects. The results from this pilot study indicate that continuous axillary brachial plexus analgesia with low dose morphine might be beneficial in patients suffering from complex regional pain syndrome of the arm.

This randomized double blind study investigates the relative efficacies of controlled analgesia (PCA) regimens in three different patient groups: epidural diamorphine 2.5mg followed by PCA bolus 1mg with a 20-min lockout (Gp1), subcutaneous diamorphine 2.5mg followed by PCA bolus with a 10-min lockout period (Gp2) and epidural diamorphine 2.5mg in 4mL of 0.125% (w/v) bupivacaine followed by a PCA bolus of 1mg diamorphine in 4mL 0.125% (w/v) bupivacaine with a 20-min lockout (Gp3). Patients were evaluated at 0, 1, 2, 3, 4, 8, 12, 16, 20, 24 and 48 h. Patients in Gp2 consumed significantly more diamorphine than those in Gp1 or Gp3 (P>0.05), but their pain scores were higher only at 1, 2 and 3 h (P>0.05) with respect to Gp3 and at 1 h with respect to Gp1. Fewer side effects (sedation, pruritis and nausea as assessed by antiemetic requirements) occurred in Gp2 compared to Gp1 (P>0.05). Fewer patients in Gp2 required catheterization than in Gp3 (P>0.05). This study indicates that the use of PCA epidural diamorphine, either alone or in combination with bupivacaine, reduces the dose requirement for analgesia but offers little clinical advantage over subcutaneous PCA diamorphine.

Postoperative nausea and vomiting (PONV) is a common adverse phenomenon following breast surgery. The efficacy of ondansetron and droperidol in preventing post–operative nausea and vomiting in women undergoing breast surgery was compared in this randomized, double–blind, placebo–controlled study. Altogether 207 women were randomly assigned to receive either a single intravenous dose of droperidol (1.25 mg) (n = 69), ondansetron (8 mg) (n = 67) or saline (n = 71) immediately after induction of general anaesthesia with thiopental, fentanyl, atracurium, nitrous oxide in oxygen and isoflurane. Complaints of nausea, vomiting and requests for rescue antiemetics were recorded during a 24-h period postoperatively. During the initial 2 h in the postanaesthesia care unit, the incidence of postoperative nausea and vomiting was 15%, 6% and 12% in the placebo, droperidol and ondansetron groups, respectively (NS). The incidence of post–operative nausea and vomiting during the first 24 h was 61%, 48% and 45% in the placebo, droperidol and ondansetron treatment groups, respectively (NS). Postoperative analgesic requirements and the length of stay in the post–anaesthesia care unit were equal in all three treatment groups. It is concluded that the intravenous pretreatment with single doses of ondansetron or droperidol did not substantially prevent postoperative nausea and vomiting after breast surgery.

We present a case of a patient submitted for extirpation of a neoplasm of the larynx, by means of carbon dioxide laser surgery. High frequency jet ventilation was applied by means of orotracheal intubation with two Teflon catheters, 2mm in external diameter and 30cm in length, attached with three equally placed strips of adhesive paper tape. One catheter was used to inject the jet volume and the other used to measure the airway pressure. The adhesive strips were moistened and FiO2 was lower than 50%. After 30 min using the laser, an airway fire was noticed. Ventilation was interrupted and the catheters were removed. The patient was reintubated with an endotracheal tube of 6mm ID and the surgical procedure was continued until the tumour was removed. Two factors contributed to the airway fire: the ignition of the lowest adhesive strip that had dried and the use of the laser in the mode of continuous pulsation.

Prolonged headache following dural puncture is an uncommon problem that may occur after a spinal tap, often as a complication of epidural anaesthesia. This problem has also been described after long–term epidural or spinal anaesthesia, myelography or spinal surgery. A case of prolonged postdural puncture headache following lumbar nerve root decompression is described in a healthy young man. No other cause could be found either clinically or with the aid of scanning by computerized tomography or magnetic resonance imaging techniques at the spinal level involved. The symptoms were successfully treated with an epidural blood patch performed seven months following the original surgical operation.

The anaesthetic management of a 25-year-old parturient with juvenile rheumatoid arthritis (Still's disease) and a difficult airway presenting for elective Caesarean section is described. Inadequate block after epidural anaesthesia necessitated general anaesthesia. This was safely accomplished by securing the airway with awake oral fibreoptic intubation before general anaesthesia was induced. The problems of performing an awake fibreoptic intubation in a pregnant patient are discussed and a simple method for performing the technique is described.