Anaesthesia-related maternal mortality.

Complications of anaesthesia leading to death in young pregnant women might be prevented if more experienced personnel could be entrusted with the job. The contribution of anaesthesia to maternal mortality in the United Kingdom is 1.7 per million pregnancies with almost similar incidence from United States. The commonest single factor responsible for anaesthesia-related death is difficult or failed intubation. A pregnant woman with a potentially difficult airway should receive aspiration prophylaxis (mechanical or pharmacological) as soon as operative delivery is anticipated. Anaesthetists should make a plan that comes into effect as soon as failure to view the larynx or to intubate the trachea becomes evident. Unsuspected difficult airway can be managed if the skill of the anaesthetists is of high standard. Pulmonary aspiration is one cause of death in obstetric anaesthesia. Regurgitation and vomiting prevention can minimise pulmonary aspiration. In regional anaesthesia, local anaesthetics toxicity is another cause of concern. This should be tackled with some safe local anaesthetics. Preventing a high spinal or epidural block involves ways to detect inadvertent injection of local anaesthetic into the cerebrospinal fluid. Postoperative care after anaesthesia in obstetric cases is very important.

Comparison of ondansetron, dexamethasone, ondansetron plus dexamethasone and placebo in the prevention of nausea and vomiting after laparoscopic tubal ligation.

Laparoscopic tubal ligation is associated with an appreciably high rate of postoperative nausea and vomiting. This study was designed to compare the effectiveness of ondansetron, dexamethasone, ondansetron plus dexamethasone or placebo in the prevention of postoperative nausea and vomiting in patients after laparoscopic tubal ligation. In a prospective, randomised, double blind placebo controlled trial, 160 ASA I-II females received one of four regimens; ondansetron 4 mg, dexamethasone 8 mg, ondansetron 4 mg plus dexamethasone 8 mg or placebo (n=40 each) intravenously immediately before induction of anaesthesia. Patients were then observed for 24 hours postoperatively. The incidence of emetic episodes in the ondansetron with dexamethasone group was lower than in the placebo (p<0.001) and ondansetron (p=0.091) and dexamethasone (p=0.143) groups. A complete response (as no postoperative nausea and vomiting) was achieved in 60% of patients given ondansetron, 63% of the patients given dexamethasone, 78% of patients given ondansetron with dexamethasone and 37% of patients received placebo. The prophylactic use of ondansetron with dexamethasone is more effective in preventing postoperative nausea and vomiting.

Intrathecal midazolam for postoperative pain relief in caesarean section delivery.

Postoperative pain relief is a growing concern to an anaesthesiologist since no single analgesic is free from side-effects. Moreover, it becomes a challenge after caesarean section delivery to provide postoperative pain relief without much sedation, respiratory depression or problems like nausea, vomiting, so that early baby acceptance and care by mother is promoted. Antinociceptive effect of midazolam is well established by now and its safety is documented. This observation was made in a blind randomised study of 40 women of ASA I/II to evaluate postoperative pain relief using intrathecal midazolam in caesarean section delivery. Group A patients (n=20) received 1.5 ml of 5% lignocaine only and group B patients (n=20) received mixture of 1.5 ml 5% lignocaine with 2 mg midazolam (preservative free) through intrathecal route at L3.4 interspace; vital parameters were monitored intra-operatively and postoperatively and Apgar score of baby in 1st and 5th minute of deliverywas assessed. It was observed intrathecal midazolam produced highly significant (p<0.001) postoperative pain relief together with anti-emetic effect and tranquillity of patients of caesarean section delivery.

Comparison between two different modes of oxygen therapy during immediate postoperative period following mitral commisurotomy.

Hypoxaemia is a common postoperative problem after thoracotomy. Oxygen therapy with continuous monitoring by pulse oximetry should be a routine practice. This study was conducted to compare the efficacy between nasal cannula and ventimask for post-thoracotomy oxygen supplementation on 20 patients divided into 2 groups of 10 each undergoing closed mitral commisurotomy. The study period was of 5 months duration from March to July, 1996. The mean oxygen saturation remained above 98% in both the groups receiving oxygen either by nasal cannula or ventimask. As there was adequate oxygenation, the cost benefit ratio favours the use of nasal cannula for routine postoperative oxygen supplementation in the closed mitral commisurotomy patients.

Role of epidural tramadol hydrochloride on postoperative pain relief in caesarean section delivery.

Two groups comprising 25 patients in each went for caesarean section delivery under epidural anaesthesia. Group I patients received 50 mg (1 ml) of tramadol hydrochloride with 14 ml of 2% lignocaine with adrenaline (1:200,000) and group II cases received 15 ml of 2% lignocaine with adrenaline (1:200,000). Both the groups of patients were comparable in age and body weight. In both the groups, there were good operative conditions, insignificant changes in pulse and blood pressure. The neonatal status was also similar in both the groups. The patients belonging to group I showed longer duration (15.39 +/- 0.45 hours) of analgesia in comparison to group II patients (2.46 +/- 0.54 hours).

Study of circle system without absorber under controlled ventilation with limited fresh gas flow.

A biphasic controlled randomised study was conducted to evaluate the differences in fresh gas flow with alterations in different anaesthetic parameters, on 15 adult female patients of American Society of Anesthetists grade I or II, who underwent elective gynaecological operations with identical premedication and anaesthetic technique in which absorber was by-passed. Intermittent positive pressure ventilation was maintained with a tidal volume of 10 ml/kg and fixed respiratory frequency of 16/minute with inspiratory:expiratory ratio of 1:2. N2O (67%) in O2, a non-depolarising muscle relaxant and a narcotic analgesic were used to maintain the anaesthesia, muscle relaxation and analgesia respectively. Phase I and II of the study were characterised by fresh gas flow of 81/minute and 5.61/minute respectively during steady state and data of both phases were collected every 30 seconds for 5 minutes. Arterial blood samples for arterial CO2 and O2 tension studies were taken towards the end of 5-minute period. In phase I a mean fractional concentration of end tidal CO2 of 3.43% +/- 0.42 (p less than 0.01) and a mean arterial tension of CO2 of 24.06 mm of Hg +/- 4.07 were obtained. In phase II mean fractional concentration of end tidal CO2 3.81% +/- 0.39 (p less than 0.01) and mean arterial O2 of 28 mm Hg +/- 2.32 were obtained. Mean arterial blood O2 saturation was above 99% and mean arterial O2 tension was above 160 mmHg in both the phases. The results were statistically significant.

Postoperative analgesia with extradural buprenorphine and pentazocine.

A randomised study of the efficacy, duration of action and side-effects of two analgesic regimens following lower abdominal surgery is described. Patients received extradural pentazocine 30 mg or extradural buprenorphine 0.3 mg to provide postoperative analgesia. Interval for the next analgesia was significantly greater after extradural buprenorphine (18.96 hours) than after extradural pentazocine (8.39 hours) (p less than 0.001). No serious side-effects were reported.