Anaphylaxis associated with, but not caused by, extradural bupivacaine.

Identifying anaphylaxis and determining its cause during anaesthesia can be very difficult. We describe a patient who suffered a life-threatening reaction which was diagnosed originally as being caused by bupivacaine. Subsequent investigation and enquiry showed that this was not so and suggested latex as the likely true cause.

Extradural diamorphine with adrenaline in labour: comparison with diamorphine and bupivacaine.

In a randomized double-blind study of 51 primigravida, we have examined the relative efficacies of bupivacaine, diamorphine or diamorphine with adrenaline given by the extradural route for relief of pain during labour. Group 1 (n = 18) received diamorphine 5 mg in 0.9% sodium chloride 8 ml; group 2 (n = 19) received diamorphine 5 mg in 0.9% sodium chloride 8 ml with 1:200,000 adrenaline; group 3 (n = 14) received 0.375% bupivacaine 8 ml. All patients received 0.375% bupivacaine 8 ml as a supplement after the initial analgesia had subsided. Patients in all groups had satisfactory and comparable analgesia 20 min after the initial injection. However, after 60 min and up to 8 h, analgesia was superior in group 2 as assessed by linear analogue pain scores, with statistical significance at 4, 6 and 8 h. Groups 1 and 2 required bupivacaine supplements less frequently than group 3 (P less than 0.001). There were no serious adverse effects in any group, but pruritus was a feature in the diamorphine groups. Diamorphine 5 mg may be used as an alternative to bupivacaine 0.375% 8 ml in the first stage of labour and provides a longer duration of action. The addition of adrenaline 1:200,000 appears to augment both the quality and duration of analgesia.

Effect of the addition of adrenaline to extradural diamorphine analgesia after caesarean section.

In a randomized double-blind study the effect of the addition of adrenaline to extradural diamorphine was assessed in 54 patients after Caesarean section. Patients received extradural diamorphine 5 mg in saline 10 ml with or without adrenaline 1 in 200,000 for postoperative pain relief. Analgesia was profound and of rapid onset in both groups. Duration of analgesia was greater in the adrenaline group (time to next analgesia 12.51 +/- 0.94 h, mean +/- SEM), than in the saline group (9.87 +/- 0.98 h) (P = 0.057). Analgesia was also more consistent in the adrenaline group, with 77% of patients having more than 8 h of good analgesia compared with 48% in the saline group (P less than 0.05). Plasma morphine concentrations, measured in 12 patients, were lower, although not significantly so, in the adrenaline group and mean time to peak concentration markedly delayed. No serious side effects were observed, but there was a higher incidence of vomiting in the adrenaline group.

Double-blind comparison of the efficacy of extradural diamorphine, extradural phenoperidine and i.m. diamorphine following caesarean section.

A randomized, double-blind study of the efficacy, duration of action and side effects of three analgesic regimens following Caesarean section is described. Patients received i.m. diamorphine 5 mg, extradural phenoperidine 2 mg or extradural diamorphine 5 mg. Analgesia was of rapid onset in all groups, as judged by reductions in linear analogue pain scores and rank pain scores. Time to next analgesia was significantly greater after extradural phenoperidine (5.96 h) and extradural diamorphine (8.39 h) than after i.m. diamorphine (3.40 h) (P less than 0.001). Itching was reported on direct questioning by 50% of patients in the extradural groups. No serious side effects were reported. Factors affecting the disposition of extradurally administered diamorphine are discussed.

Effect of anaesthesia and surgery on the pre-S-phase cell cycle kinetics of mitogen-stimulated lymphocytes of previously healthy people.

The influence of general anaesthesia, and of operative surgery, on immune responsiveness was studied in blood obtained from 26 women undergoing laparoscopic sterilization (minor operation group) and in 14 women undergoing abdominal hysterectomy (major operation group). Since immunity depends ultimately on clonal expansion of lymphocytes, the growth potential of peripheral blood lymphocytes was studied in tissue culture by mitogen stimulation. There was no evidence of any change in either the number of responding cells (those that have left the resting G0-phase and responded to mitogen stimulation by entering the G1-phase of the first cycle of growth) or in the rate at which cells grow in volume during the period of study. It was concluded that there was no evidence that anaesthesia, or surgery, impaired this aspect of the immune response in our patients, but the design of the experiments does not allow comment on other aspects of the immune response such as antigen presentation, immunoregulation and effector mechanisms, which are superimposed on the basic clonal expansion mechanisms studied in this investigation. Incidentally, we noted that the standard method for isolation of lymphocytes from peripheral blood frequently yielded highly contaminated preparations: if this fallacy was not appreciated, tests with contaminated lymphocytes could be misinterpreted as showing depression.

The extension of labour epidural analgesia for Caesarean section.

Seven hundred and twenty-two patients who received epidural analgesia during labour were delivered by Caesarean section. The block was extended in 554 patients to provide analgesia for surgery. In twenty-one cases incomplete analgesia necessitated general anaesthesia. The main complications were maternal hypotension (15.9%) and vomiting (17.1%). Almost all patients expressed enthusiasm for the technique.

Post-partum sterilisation--an anaesthetic hazard?

A case of acid aspiration pneumonitis which occurred in the puerperium is described. Gastric aspirate was collected in fifty patients undergoing postpartum sterilisation. Results of pH and volume suggest these patients should be regarded as potential candidates at risk of developing Mendelson's syndrome.