Effect of epidural morphine on minimum alveolar concentration of isoflurane in humans.

BACKGROUND AND AIMS: The anaesthetic potency of volatile anaesthetic agents is measured by the minimum alveolar concentration (MAC) required to suppress response in 50% of subjects. We studied the effect of epidural morphine on MAC of isoflurane in humans. SETTINGS AND DESIGN: A prospective single-blind study designed to study the effect of epidural morphine on MAC of isoflurane. SUBJECTS AND METHODS: Forty-eight patients were randomly divided into two groups - Group I patients received 3 mg morphine in 10 ml saline, and Group II patients received 10 ml saline epidurally. Anaesthesia was induced with isoflurane in oxygen and nitrous oxide. Later nitrous oxide was discontinued and MAC of isoflurane determined using modified Dixon's method of sequential sampling. RESULTS: Epidural morphine resulted in a significant reduction in MAC of isoflurane, 0.98 vs. 1.14 in control group (p<0.05). CONCLUSIONS: Epidural administration of 3 mg morphine in 10 ml saline decreased the MAC of isoflurane.

Stress ulcer prophylaxis in patients on ventilator.

The objective of the study was to assess the efficacy of the H2-receptor antagonists and sucralfate for the prophylaxis of stress ulcer in patients on a ventilator in an intensive care unit in the general intensive care unit of our institute. A randomized, clinical controlled trial was conducted. Fifty-two critically ill patients, who required mechanical ventilation for more than 24 hours, were randomly divided into 3 groups. Group I received ranitidine 50 mg (intravenous) 8 hourly, group II received tablet sucralfate 1 g 8 hourly through a Ryle's tube, whereas group III was not given any drug. The incidence of upper gastrointestinal bleed, change in gastric pH and growth of gram-negative organisms in the gastric juice and bronchoalveolar lavage (BAL) culture were noted and analysed. The treatment groups were similar with respect to the baseline characteristics. The incidence of upper gastrointestinal bleeding was similar in the ranitidine (12.5%) and sucralfate groups (14.35%) but was high in the control group (57.14%). The mean gastric pH was significantly low in the control group (mean pH 2.07) compared to the ranitidine (mean pH 5.25) and sucralfate groups(mean pH 3.54)(p < 0.05). The incidence of positive culture for gram-negative organisms was significantly high in the ranitidine group (75%) in comparison with the sucralfate group (33.33%) (p < 0.002). However, the incidence of positive growth in the BAL culture was similar in all three groups. We conclude that both ranitidine and sucralfate are equally effective in decreasing the incidence of upper gastrointestinal haemorrhage and other stress- related lesions. Though ranitidine was more effective in increasing the gastric pH, the incidence of gastric colonization was higher in the ranitidine group compared to the sucralfate group.

Laryngeal changes following long-term stenting with polyvinyl chloride tubes.

BACKGROUND. To treat tracheal stenosis and permit wound healing to occur an inert stent is required which resists the contraction process and prevents re-stenosis. The newer stents of polyvinyl chloride are not readily available in India and endotracheal tubes are used in many centres. In our centre polyvinyl chloride tubes are used nasotracheally for prolonged periods. We prospectively studied the pattern of laryngeal changes that occur because of prolonged nasotracheal stenting with polyvinyl chloride tubes. METHODS. The incidence and pattern of laryngeal changes due to stents was prospectively studied at the time of removal of stents, using an operating microscope. Twenty-nine patients underwent tracheal reconstructive surgery for tracheal stenosis (post-intubation or post-tracheostomy) and tracheal injuries. RESULTS. Twelve different lesions were noted and their pattern was related to the period of stenting. Fibrosis, fibrous band formation and webs were noted after four weeks. A high incidence of laryngeal changes was seen in all age groups with an overall incidence of 79% (males 79%; females 88%; adults 82%, children 75%). The mean (SD) duration of stenting was 50 (33) days. Patients with laryngeal changes had a significantly (p < 0.05) longer duration of stenting [56 (34) days] compared to those without any lesion [29 (15) days]. CONCLUSIONS. After four weeks of stenting the severity and incidence of laryngeal changes increase. We recommend restriction of the use of polyvinyl chloride stents to less than four weeks to prevent permanent laryngeal damage.

A profile of nutritional practices and its cost in an intensive care in India.

In a retrospective study fifty patients admitted to a combined medical and surgical intensive care unit were surveyed to see the pattern of nutritional support. The routine practices of initial assessment and monitoring of the nutritional state, ordering and technique of feeding, routes of administration and complications were noted over a 3 week period. This gives an idea of the pattern of care and problems associated with nutritional support of the critically ill in this part of the world. The average cost of parenteral nutrition for three weeks was approximately Rs. 25,960 ($865 approx.) per patient.

Postoperative pulmonary complications in patients with preoperative lung disease.

A prospective study was carried out on the incidence of pulmonary complications in 728 patients who underwent major surgical procedures at a reputed hospital in New Delhi. These patients were preoperatively assessed on the basis of history, clinical examination and bedside pulmonary function tests including PEFR, VC, FVC and FEV1. On the basis of these criteria, 212 patients had significant preoperative pulmonary disease, while 516 had normal lung functions. Postoperative pulmonary complications developed in 7.69 per cent of the patients. They were more frequent in smokers (P < 0.001) and in those with preoperative pulmonary dysfunction (P < 0.001). Their incidence was greater following thoraco-abdominal and musculoskeletal and miscellaneous operations compared to lower abdominal surgery (P < 0.001). The incidence was also higher following exposure to general anaesthesia compared to regional anaesthesia (P < 0.05). Pneumonia and atelectasis were the most common postoperative pulmonary complications. It was observed that the recovery of pulmonary functions was delayed in patients who developed postoperative pulmonary complications.