A randomised trial comparing 5 mL/kg and 10 mL/kg of pentastarch as a volume preload before spinal anaesthesia for elective caesarean section.

BACKGROUND: Colloid solutions are more effective at preventing hypotension than crystalloids when used as a volume preload before caesarean delivery under spinal anaesthesia. The ideal volume to infuse has not been established. METHOD: In a randomised double-blind trial 70 women presenting for elective caesarean section received either 5 mL/kg of pentastarch (group A) or 10 mL/kg of pentastarch (group B) as a volume preload before spinal anaesthesia. Hypotension was defined as a systolic pressure below 90 mmHg or a decrease of 30% from a baseline value. Treatment was with 6-mg increments of ephedrine until resolution. RESULTS: In group B, 7/35 patients (20%) developed hypotension, significantly fewer than the 15/35 (42.8%) in group A (P<0.05). The patients in group B also required less ephedrine (total in group, 114 mg) than those in group A (total in group, 198 mg) CONCLUSIONS: Pentastarch, 10 mL/kg is more effective than 5 mL/kg at preventing hypotension following spinal anaesthesia for caesarean delivery.

Loss of split thickness skin grafts due to non-group A beta-haemolytic streptococci.

Over a 17-month period 77 patients requiring a split skin graft for a burn injury have suffered loss of previously well taken graft due to the growth of a beta-haemolytic streptococcus. Of these only 42 were streptococci of Lancefield group A (Streptococcus pyogenes); 16 were group B, 3 group C and 16 group G. Some strains of groups B, C and G produce cytopathic and spreading factors capable of destroying the new skin graft and regenerating epithelium. We suggest that the non-group A streptococci may be more pathogenic than previously recognised in this particular respect.

Simulation as a training and assessment tool in the management of failed intubation in obstetrics.

Failed intubation has been a serious problem in obstetric anaesthesia in the UK. The current study was designed to assess the use of the 'ACCESS' simulator (Anaesthetic Computer-Controlled Emergency Situation Simulator) to evaluate our trainees' performance in an obstetric failed intubation setting. Using a scoring system based on our department's failed intubation drill in obstetrics, 13 junior anaesthetists were recruited for the study and all took part in the simulation exercise. Six weeks later they were all tutored as a group or individually on the important points raised from their first simulations. Two weeks after that, 12 of the candidates were re-tested, and 11 scored better than their first time. The results were confidential and the authors ensured all feedback was of a positive nature. The study shows that a simulator may be a useful tool for assessment of performance in a simulated emergency situation when combined with practice and formal teaching.

Overtransfusion as a possible cause of split skin graft loss.

A child who underwent burns surgery received excessive transfusion of red blood cells during operation and subsequently suffered severe skin graft and donor site loss. The possible causes are discussed and hyperviscosity is suggested to be the most probable.

The use of semi-permeable membranes for wound management.

This paper reports a study comparing bags made from expanded polytetrafluoroethylene semi-permeable membranes and standard plastic bags to treat burns of the hands. There was much less maceration in the PTFE bag, which allowed easier assessment of the extent and depth of burn, and only one daily dressing change was needed. The two types of bag were similar with regard to ease of use, low bacterial contamination and allowing good mobilisation of the hand. Ease of use has meant that a greater number of patients with superficial burns can be treated as outpatients and many are able to do their own daily dressing change, so fewer attendances at the clinic are needed.

Comparison of pentastarch and Hartmann's solution for volume preloading in spinal anaesthesia for elective caesarean section.

We studied 160 patients undergoing elective Caesarean section under spinal anaesthesia who received a preloading volume of 15 ml kg-1 of 10% pentastarch in 0.9% saline, or Hartmann's solution, in a prospective, randomized, double-blind study. We compared the incidence of spinal-induced hypotension in each group. Hypotension was defined as a decrease in systolic arterial pressure to less than 70% of baseline values or < or = 90 mm Hg, whichever was the greater. The groups were comparable in physical characteristics and there was no serious morbidity. Fetal outcome was similar in both groups. Significantly more patients in the Hartmann's group (n = 38, 47.5%) developed hypotension than in the pentastarch group (n = 10, 12.5%) (P < 0.0001). Linear regression analysis showed that the only significant variable was type of fluid used. Blood glucose concentrations were not related to the presence of hypotension. We conclude that starches may be suitable for preloading in Caesarean section under spinal anaesthesia and provide an alternative to the aggressive use of vasoconstrictors.

Silent myocardial ischaemia in patients undergoing transurethral prostatectomy. A study to evaluate risk scoring and anaesthetic technique with outcome.

Ninety four patients undergoing transurethral resection of the prostate underwent Holter electrocardiographic monitoring pre- and postoperatively. There was no difference in silent myocardial ischaemia incidence or load between the spinal (n = 60) and the general anaesthesia (n = 34) groups. Ischaemic heart disease and a higher Detsky score both significantly increased the incidence of silent myocardial ischaemia but not the ischaemic load of those patients that actually demonstrated ischaemia. In this specific surgical population, not undergoing cardiac or vascular surgery, both ischaemic heart disease and cardiac risk scores are poor predictors of ischaemic load. Merely the presence of short duration silent myocardial ischaemia probably has little predictive value for postoperative adverse outcome.

Peri-operative silent myocardial ischaemia in patients undergoing lower limb joint replacement surgery: an indicator of postoperative morbidity or mortality?

One hundred and twenty-seven patients undergoing major lower limb joint replacement surgery were studied to determine the incidence of silent myocardial ischemia and to ascertain any link between pre-operative cardiac risk factors, silent myocardial ischaemia and postoperative morbidity. Patients underwent ambulatory ECG monitoring for 4 days (on the pre-operative night and for 3 days postoperatively). Postoperative cardiorespiratory symptomatology and morbidity was assessed by questionnaire at 3 months. Eighty-seven patients had risk factors for silent myocardial ischaemia; 42 patients (30 with risk factors) had peri-operative silent myocardial ischaemia. The median ischaemic loads (range) were 1.04 (0.32-13.31) min.h-1 pre-operatively and 5.53 (0.26-56.39), 6.69 (0.04-42.71) and 1.23 (0.1-53.74) min.h-1 on postoperative days 1-3, respectively. Risk factors did not predict the occurrence of silent myocardial ischaemia or an increased ischaemic load pre-operatively or overall postoperatively. New symptoms (chest pain, palpitations, breathlessness or fatigue) were associated with both silent myocardial ischaemia and ischaemic load (p < 0.05). Thus cardiac risk factors do not predict the occurrence of silent myocardial ischaemia or adverse outcome. Peri-operative silent myocardial ischaemia was associated with increased postoperative fatigue.