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SUMMARY Ten healthy unpremedicated male volunteers were exposed to an average inspired concentration of 3.6% desflurane (1–653) in oxygen for 89 (SD 17) min. Standard haematological and biochemical tests were performed before (control) and immediately after exposure and at 4, 24, 72 and 192 h. Liver function was assessed at these times by determining total and unconjugated (indirect) bilirubin, and plasma concentrations of aspartate amino transferase, alanine amino transferase, γglutamyl transpeptidase and alkaline phosphatase. Renal function was assessed by examining the urine microscopically for leucocytes, red blood cells, casts and crystals at these times, and creatinine clearance and urine concentrating ability were determined before and 24 and 72 h after exposure. Two additional and sensitive tests of renal integrity were performed before and 4 and 24 h after anaesthesia: measurement of urinary retinol-binding protein and β-N-acetyl-D-glucosaminidase. Serum inorganic fluoride was determined immediately before and 1, 4, 24, 48, 72 and 192 h after anaesthesia. Urinary inorganic and organic fluoride concentration and excretion rate were determined before and 24, 48, and 72 h after anaesthesia. There were no significant changes in any measured haematological or biochemical variable (other than an increase in total white cell count from 5.9 (1.3) to 8.3 (1.1) × 109 litre−1 immediately after exposure) nor in liver or renal function tests. There was no increase in serum or urinary inorganic fluoride or urinary non-volatile organic fluoride concentrations.

This review examines the evidence from published data concerning the incidence of moderate-severe and of severe pain after major surgery, with three analgesic techniques; intramuscular (i.m.) analgesia, patient controlled analgesia (PCA), and epidural analgesia.A MEDLINE search of the literature was conducted for publications concerned with the management of postoperative pain. Over 800 original papers and reviews were identified. Of these 212 papers fulfilled the inclusion criteria but only 165 provided usable data on pain intensity and pain relief. Pooled data on pain scores obtained from these studies, which represent the experience of a total of nearly 20,000 patients, form the basis of this review.Different pain measurement tools provided comparable data. When considering a mixture of three analgesic techniques, the overall mean (95% CI) incidence of moderate-severe pain and of severe pain was 29.7 (26.4-33.0)% and 10.9 (8.4-13.4)%, respectively. The overall mean (95% CI) incidence of poor pain relief and of fair-to-poor pain relief was 3.5 (2.4-4.6)% and 19.4 (16.4-22.3)%, respectively. For i.m. analgesia the incidence of moderate-severe pain was 67.2 (58.1-76.2)% and that of severe pain was 29.1 (18.8-39.4)%. For PCA, the incidence of moderate-severe pain was 35.8 (31.4-40.2)% and that of severe pain was 10.4 (8.0-12.8)%. For epidural analgesia the incidence of moderate-severe pain was 20.9 (17.8-24.0)% and that of severe pain was 7.8 (6.1-9.5)%. The incidence of premature catheter dislodgement was 5.7 (4.0-7.4)%. Over the period 1973-1999 there has been a highly significant (P0.0001) reduction in the incidence of moderate-severe pain of 1.9 (1.1-2.7)% per year.These results suggest that the UK Audit Commission (1997) proposed standards of care might be unachievable using current analgesic techniques. The data may be useful in setting standards of care for Acute Pain Services.

We conducted a survey of the incidence of Postoperative Residual Curarisation (PORC) in two groups of patients following the use of atracurium or vecuronium. In the first group (B) the neuromuscular blocking drugs were administered by bolus dosing, and in the second group (I) by continuous fusion. On arrival in the recovery room, neuromuscular function was assessed both by compound evoked electromyogram (EMG) in a train of four pattern and also clinically, by the ability to sustain a headlift for > 5 seconds, and to cough. Results were obtained from 150 patients (100 in group B and 50 in group I). The incidence of PORC, as defined by a train of four ratio of < 0.7, on arrival in the recovery room was 12% in group B, and 24% in group I. Clinical criteria of adequate neuromuscular reversal revealed different results, with the majority of patients being unable to perform either clinical test on arrival in recovery. Those patients in whom a peripheral nerve stimulator was used intra-operatively did not have a reduced incidence of PORC. We have demonstrated that PORC is still a common occurrence even with intermediate duration of action neuromuscular blocking drugs.

Ten healthy unpremedicated male volunteers were exposed to an average inspired concentration of 3.6% desflurane (I-653) in oxygen for 89 (SD 17) min. Standard haematological and biochemical tests were performed before (control) and immediately after exposure and at 4, 24, 72 and 192 h. Liver function was assessed at these times by determining total and unconjugated (indirect) bilirubin, and plasma concentrations of aspartate amino transferase, alanine amino transferase, gamma-glutamyl transpeptidase and alkaline phosphatase. Renal function was assessed by examining the urine microscopically for leucocytes, red blood cells, casts and crystals at these times, and creatinine clearance and urine concentrating ability were determined before and 24 and 72 h after exposure. Two additional and sensitive tests of renal integrity were performed before and 4 and 24 h after anaesthesia: measurement of urinary retinol-binding protein and beta-N-acetyl-D-glucosaminidase. Serum inorganic fluoride was determined immediately before and 1, 4, 24, 48, 72 and 192 h after anaesthesia. Urinary inorganic and organic fluoride concentration and excretion rate were determined before and 24, 48, and 72 h after anaesthesia. There were no significant changes in any measured haematological or biochemical variable (other than an increase in total white cell count from 5.9 (1.3) to 8.3 (1.1) x 10(9) litre-1 immediately after exposure) nor in liver or renal function tests. There was no increase in serum or urinary inorganic fluoride or urinary non-volatile organic fluoride concentrations.

The characteristics of neuromuscular block induced by doxacurium were compared in patients with and without renal function. Seventeen patients with end stage chronic renal failure and 18 patients with normal renal function were anaesthetized with 0.5% halothane and nitrous oxide in oxygen and received doxacurium in an initial dose of 25 micrograms kg-1 (estimated from available data as an ED95 dose), with incremental doses of 5 micrograms kg-1. At the end of surgery, residual neuromuscular block was antagonized with either edrophonium 1.0 mg kg-1 or neostigmine 0.08 mg kg-1. There was no significant difference between the mean maximum blocks achieved with doxacurium: 17.4% (renal failure group) and 11.6% (control group) of control twitch heights, or between the mean times to achieve maximum block (10.9 min and 10.8 min, respectively). The mean duration of action of doxacurium, indicated by the time for twitch height to recover to 25% of control, was longer in the renal failure group (120.8 min vs 66.7 min in the control group) (ns). Similarly, the mean duration of action of increments was longer in the renal failure group (27.4 min vs 20.5 min in the control group). The rate of spontaneous recovery from doxacurium as indicated by the time for twitch height to recover from 0 to 5%, 5 to 10% and 10 to 25%, was not significantly different in the two groups. Antagonism of doxacurium was achieved more reliably with neostigmine than with edrophonium in both groups. The administration of doxacurium was associated with minimal cardiovascular effects.

The inhalation anesthetic, desflurance (I-653), is a methyl ethyl ether halogenated entirely with fluorine and differing from isoflurance only in the substitution of fluorine for chlorine on the alpha-ethyl carbon. Relative to presently used potent inhalation anesthetics, desflurane has low blood/gas (0.42) and oil/gas (18.7) partition coefficients. These indicate that it will undergo rapid washin and washout (and hence rapid induction of and recovery from anesthesia) and have a MAC value of about 5%. In the present study we demonstrate that desflurane possesses these characteristics in healthy young volunteers. After a 10-min exposure to desflurane the ratio of alveolar (FA) (determined by end-tidal sampling) to inspired (FI) concentration (FA/FI) was 0.82. Washout was similarly rapid; 10 min after discontinuing administration of desflurane, the alveolar concentration relative to the last concentration during administration of anesthetic (FAO) was 0.11 (FA/FAO). These values are similar to those for nitrous oxide. Volunteers responded to commands an average of 2.7 min after discontinuing anesthetic administration. The values for MAC-awake and MAC (the latter determined by tetanic stimulation of the ulnar nerve using surface electrodes) were 2.42% and 4.58% and the ratio of the former to the latter was 0.53.

This study was designed to evaluate the usefulness of three commonly used tests of psychomotor function and one test of short-term memory in assessing recovery from a brief nitrous oxide, oxygen and halothane anaesthetic. Twenty-six female patients undergoing minor gynaecological surgery were allocated to one of three treatment groups depending on premedication (placebo, low dose and high dose). Immediate recovery was most rapid in the placebo group. Both the tests of simple reaction time and picture recall were able to differentiate between the post-anaesthetic recovery of the high-dose group and that of the other two groups. Neither component of the letter cancellation test showed a clear difference in recovery pattern. Tests of critical flicker fusion were too unreliable to be of use in clinical decision making. Our results suggest that tests of reaction time and memory were more sensitive than letter cancellation in assessing recovery.

Summary The effect of intravenous ketanserin on the pressor response to sternotomy was studied in 36 patients undergoing coronary artery surgery. Two doses of the drug (10 mg and20 mg) were compared with a placebo injection of saline. After induction of anaesthesia, haemodynamic variables were measured until the institution of cardiopulmonary bypass. Plasma and platelet 5-hydroxyindoles and 5-hydroxytryptamine were measured in a subset of 13 patients. Ketanserin induced a dose-dependent amelioration of the pressor response to sternotomy. Plasma 5-hydroxyindoles and platelet 5-hydroxytryptamine levels did not correlate with clinical response. The increased effectiveness of the higher dose of ketanserin may be due to an effect other than serotonin antagonism.

The effect of the administration of a 50 mg dose of an angiotensin converting enzyme inhibitor (captopril) on the mean arterial pressure following sternotomy in 13 patients undergoing coronary artery bypass surgery was indistinguishable from the response in 13 patients who had not received the drug.

Summary Forty patients undergoing day-case anaesthesia for surgical extraction of third molar teeth received either lysine acetylsalicylate 1.8 g in 10 ml of saline intravenously or a placebo injection of 10 ml of saline intravenously just prior to induction of anaesthesia. Lysine acetylsalicylate was associated with a significantly more satisfactory postoperative recovery overall. However, there was no significant difference in mean pain scores between the two treatment groups at 1, 6, 12 or 24 hours following administration. Both treatment groups self administered additional oral analgesics to the same extent during the first 24 hours following surgery.

Cricothyroid puncture in the process of minitracheostomy may encounter aberrant blood vessels and require surgical exploration.

A case report of severe pruritus following spinal anaesthesia in an 80-year-old man is presented. The pathophysiology of pruritus is discussed and the possible causes in the case reported are outlined.