Failure of rectal diclofenac to augment opioid analgesia after cholecystectomy.

The analgesic efficacy of a single 100-mg suppository of diclofenac sodium given after elective cholecystectomy was studied in 30 healthy patients in a double-blind randomised controlled manner. The mean 24-hour postoperative morphine consumption of the placebo group and the diclofenac group was similar (45 mg). Analysis of the cumulative hourly morphine consumption from the patient-controlled analgesia system failed to show any statistically significant differences between the groups. Peak expiratory flow rate, forced expiratory volume at 1 second and forced vital capacity decreased 24 hours after operation to less than 50% of pre-operative values in both groups. Subjective experiences of pain, nausea and drowsiness assessed by linear analogue scoring were similar in both groups.

Detection of cerebral hypoperfusion during cardiopulmonary bypass. Continuous measurement of cerebral venous oxyhaemoglobin saturation during myocardial revascularisation.

We measured continuously cerebral venous oxyhaemoglobin saturation (SjvO2) using a 4F fibreoptic catheter in 11 patients scheduled for elective myocardial revascularisation. The aims of this study were to assess the Oximetrix 3 computer and Opticath 40 cm catheter during moderate hypothermic cardiopulmonary bypass, and identify epochs of cerebral hypoperfusion (SjvO2 < 54%). Radial artery pressure, brain electrical activity, arterial and cerebral venous oximetry (dual oximetry), end-tidal CO2 and nasopharyngeal temperature were recorded continuously in each patient. Following in vivo calibration of 11 continuous SjvO2 catheters and monitor, 57 simultaneous, paired recordings were additionally taken. The mean difference between the catheter SjvO2 and the in vitro laboratory derived value was 0.34%, with a 95% confidence interval -3.2% to 2.4%. In 10 patients SjvO2 decreased below normal at rewarming and myocardial reperfusion: mean lowest value 37%, range 19%-55%. Reduced SjvO2 were associated with a decrease in perfusion pressure (r = 0.292, 80 DF, p = 7.7* 10(-3)), and with an increase in nasopharyngeal temperature (r = -0.46, 115 DF, p = 2.7* 10(-7)) after moderate hypothermia. The Oximetrix 3 computer and Opticath 40 cm catheter provided reliable and accurate continuous monitoring of SjvO2 during nonpulsatile cardiopulmonary bypass involving hypothermia with haemodilution and identified rewarming as the period of greatest risk of global cerebral hypoperfusion.

An evaluation of the Datex Normac anaesthetic agent monitor.

A new monitor for volatile anaesthetics, the Datex Normac, was assessed in the laboratory and operating theatre. The instrument had a warm up time of 90 minutes from cold, but only 5 minutes from standby. Zero drift was less than 0.01% over 7 hours, and repeated measurements of gain showed a coefficient of variation of less than 1%. However, gain drift of 6% occurred when the instrument was switched off between periods of use. Signal noise was less than 0.02 vol% on a new instrument, but was about six times greater on an instrument that had been in use for a year. The response time of 550 ms is short enough to allow breath by breath monitoring. When the instrument was calibrated on the enflurane setting, measurements made on the enflurane, halothane and isoflurane settings were accurate to within 6% of the reading. This is satisfactory for clinical purposes, but not for more demanding applications. Calibration canisters are available, and two that we tested were accurate to better than 0.1 vol%. Nitrous oxide, carbon dioxide and water vapour have very small effects on the monitor. The instrument provided trouble-free monitoring in theatre.

Maternal oxygenation during normal labour.

Arterial oxyhaemoglobin saturation (SaO2) was monitored continuously during normal labour in 33 healthy parturients receiving pethidine and nitrous oxide for analgesia. Sixteen (49%) had episodes exceeding 10 s duration when SaO2 was less than 90% (mean 83.7%, range 89-60%). Two women had multiple episodes of profound hypoxia with SaO2 less than 70%.

Outcomes following coronary artery bypass grafting and percutaneous transluminal coronary angioplasty in the stent era: a prospective study of all 9890 consecutive patients operated on in Scotland over a two year period.

OBJECTIVE: To determine current outcomes of percutaneous transluminal coronary angioplasty (PTCA) and coronary artery bypass grafting (CABG). DESIGN: The Scottish coronary revascularisation register provided prospectively collected data on case mix and in-hospital complications for all revascularisation procedures between April 1997 and March 1999 (4775 PTCA; 5115 CABG). Linkage to routine hospital discharge and death data provided follow up information on survival and repeat revascularisation. RESULTS: Stents were used in 51% of PTCA procedures. CABG patients were older, had more severe coronary disease, and had greater comorbidity. PTCA was more likely to be undertaken as an urgent or emergency procedure. Perioperative death and urgent surgery followed 0.3% and 0.6% of PTCA procedures, respectively. Case fatality rates were higher following CABG, with 6.7% dead within two years compared with 3.4% following PTCA. PTCA was more often followed by readmission for ischaemic heart disease, repeat angiography, or revascularisation: 22.8% of patients had repeat revascularisation within two years, compared with 1.8% following CABG. CONCLUSIONS: The severity of coronary heart disease was greater than in previously published registry studies and randomised trials. Despite this, overall survival figures were comparable and repeat revascularisation rates lower, particularly following PTCA. Perioperative death and urgent surgery following PTCA were also lower. These favourable outcomes may be attributable, in part, to increased use of bail out and elective stenting.