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Biomedical subjects

N Mehta

Publications and source records attributed to N Mehta.

98 records · Page 6Linked to original sources
PubMedDate not supplied

Prevalence and predictors of the prone sleep position among inner-city infants.

CONTEXT: The prone sleep position is associated with an increased risk of sudden infant death syndrome (SIDS), but few studies have assessed factors associated with the choice of infant sleep position. OBJECTIVES: To describe infant sleep position in a cohort of infants born to predominantly low-income, inner-city mothers and to identify predictors of the prone sleep position in this population. DESIGN: Prospective birth cohort study. PATIENTS AND SETTING: Three hundred ninety-four mother-infant dyads, systematically selected from 3 District of Columbia hospitals between August 1995 and September 1996. Mothers were interviewed shortly after delivery and again at 3 to 7 months postpartum. MAIN OUTCOME MEASURES: Position in which infants were placed for sleep on the night prior to the 3- to 7-month interview. RESULTS: At 3 to 7 months of age, 157 infants (40%) were placed for sleep in the prone position. Independent predictors of prone sleep position included poverty (odds ratio [OR], 1.81; 95% confidence interval [CI], 1.10-2.99), black race (OR, 2.06; 95% CI, 1.05-4.04), presence of infant's grandmother in the home (OR, 1.83; 95% CI, 1.11-3.00), and intent, as measured shortly after delivery, to place the infant in the prone position (OR, 2.28; 95% CI, 1.44-3.60). Importantly, of the 43 mothers who observed their infants in the prone sleep position while in the hospital, 40 (93%) intended to place their infants prone at home. CONCLUSIONS: A substantial proportion of infants in this predominantly low-income population were placed in the prone sleep position. Educational efforts should address both initial intentions and reinforcement of the correct sleep position, once initiated. Hospitals should ensure that healthy newborn infants are placed in the supine sleep position during the postpartum hospital stay.

Humans↗
PubMedDate not supplied

Residual poliomyelitis of lower limb-pattern and deformities.

The pattern of muscle paralysis and paresis in the lower limbs has been studied in 1356 children with 1800 poliomyelitic limbs, revealed that more than two-third (68 = 55%) muscles were affected, with the ratio of paresis and paralysed muscles were 1.89:1.00. The muscles most frequently affected were tibialis anterior (1516), quadriceps (1465) and tibialis posterior (1435) while tibialis anterior (1070), tibialis posterior (820) and quadriceps (766) were most commonly paralysed in descending order. The tibialis anterior which leads in paralysis group, has come last in order of frequency of paresis. The highest segmental incidence of affection of muscles found in second to fourth lumbar segments while muscle paralysis is found in fourth lumbar spinal segment. The commonest deformities encountered in residual poliomyelitis are flexion-abduction contracture hip, flexion contracture knee and valgus deformity foot.

Child, Preschool↗
PubMedDate not supplied

Control of tachycardia and hypertension following coronary artery bypass graft surgery: efficacy and haemodynamic effects of esmolol.

Hypertension following coronary artery bypass grafting is not uncommon, especially in patients having good left ventricular function. It is often accompanied by tachycardia. The purpose of this study is to determine the efficacy of esmolol in the treatment of tachycardia and hypertension immediately following cardiopulmonary bypass and to study other haemodynamic effects of esmolol. Thirty patients undergoing elective [corrected] coronary artery bypass grafting were included in this prospective study. Morphine-based anaesthetic technique along-with standard bypass techniques were used in all the patients. The study was performed in the operating room about 30-45 minutes after the termination of cardiopulmonary bypass. Patients having a heart rate of more than 90 bpm and systolic blood pressure of more than 130 mm Hg without any inotropic support were included and randomly assigned to esmolol or control group. Esmolol was administered in a bolus dose of 500 micrograms/kg followed by infusion of upto 100 micrograms/kg/min. The patients in the control group were administered comparable volumes of normal saline. Baseline haemodynamic measurements were obtained just before the administration of esmolol or normal saline and were repeated after 5, 10, 15, 30 and 45 min. The baseline measurement in both the groups showed that patients were maintaining a state of hyperdynamic circulation with high systolic blood pressure (esmolol group 148 +/- 15 mm Hg, control group 140 +/- 8 mm Hg; p = NS), heart rate (esmolol group 128 +/- 17 bpm, control group 127 +/- 17 bpm; p = NS) and cardiac index (esmolol group 3.1 +/- 1 L/min/m2, control group 3.3 +/- 0.5 L/min/m2; p = NS). Esmolol decreased systolic blood pressure (p < 0.001), heart rate (p < 0.01) and cardiac index (p < 0.05) at five minutes. These changes persisted throughout the study period. The left ventricular stroke work index decreased at five minutes (p < 0.05) and remained so till 30 minutes. The maximum fall in heart rate (15%) and systolic blood pressure (16%) was observed at 45 minutes. There were no haemodynamic changes in the control group except that cardiac index, stroke volume and left ventricular stroke work index increased at five minutes. We conclude that esmolol lowers the indices of cardiovascular work in patients who demonstrated hyperdynamic circulation. This was achieved by decreasing the heart rate and systolic blood pressure which was accompanied by decrease in cardiac index and left ventricular stroke work index.

Adrenergic beta-Antagonists↗
PubMedDate not supplied

Exudative pleural effusions in patients over forty years of age--an analysis of seventy-six patients.

A prospective study of 76 consecutive patients over the age of 40 years, with exudative pleural effusion, was undertaken to determine the common causes of such a clinical condition. Malignant pleural effusions were the most common in this series, found in 49 patients (64.47%), all but one being metastatic from elsewhere. Forty were secondary to a carcinoma of the bronchus, 3 from carcinoma of the breast, 1 each from carcinoma of the ovary, oesophagus, and larynx; lymphoma accounted for the remaining 2. Infective causes accounted for 24 of the effusions (31.57%). Of the infections, tuberculosis was the most common, accounting for 17 of the 24. Other infective causes included bacterial empyemas in 4, ruptured amoebic liver abscess in 2, and actinomycosis in 1. Pancreatitis, pulmonary thromboembolism, and a post-cardiotomy syndrome were diagnosed in 1 patient each, while the diagnosis remained unknown in the remaining 5 patients. In 2 patients the diagnosis was made on autopsy.

Adult↗
PubMedDate not supplied

Anaesthetic management of patients undergoing surgery for tachyarrhythmias. Initial experience with 16 patients.

Sixteen patients suffering from various cardiac arrhythmias were treated surgically. Intraoperative computerised electrophysiologic mapping was used in 14. Thirteen patients were suffering from Wolff-Parkinson-White syndrome. They underwent surgical division or cryoablation of accessory pathways. Two patients who had rheumatic mitral stenosis with left atrial clot underwent "Maze III" procedure with open mitral commissurotomy and clot removal. One patient with paroxysmal refractory ventricular tachycardia and a left ventricular aneurysm had an aneurysmectomy with subendocardial resection of the arrhythmic focus. All antiarrhythmic medications were discontinued preoperatively. Morphine was the principal anaesthetic agent, supplemented with halothane. Muscle relaxation was provided with pancuronium bromide. The various problems encountered included hypotension and arrhythmia during placement of epicardial band array for mapping (4 patients), ventricular tachycardia during internal jugular vein cannulation (1 patient) and continuance of delta wave after cryoablation in 2 patients. Halothane may have interfered with electrophysiologic mapping and accurate localization of accessory pathway leading to persistence of delta wave. The choice of anaesthetic agents should be guided by the electrophysiologic effects and potential influence of these agents on the accessory pathways.

Adult↗
PubMedDate not supplied

Thrombolytic therapy for prosthetic valve thrombosis in Third World countries.

In order to clarify the role of thrombolytic therapy for treatment of prosthetic valve thrombosis, all cases admitted in the intensive care unit (ICU), between March 1987 and March 1997 with the diagnosis of prosthetic valve thrombosis and treated with streptokinase, were analysed. In total, 42 patients with clinical and echocardiographic evidence of left side tilting disc prosthetic valve thrombosis were treated. All the patients had only mitral valve prosthesis involvement. Streptokinase was administered as a bolus of 2.5 lac units over 30 minutes followed by 1 lac units/hour for 48-72 hours. Thirty-seven (88%) patients had successful thrombolysis. Overall mortality occurred in 9.5 percent patients due to systemic embolism and bleeding complications. Serial clinical, radiological and echocardiographic studies showed successful thrombolysis in 88 percent patients. This study demonstrates that streptokinase therapy is safe and effective first line treatment for left-sided prosthetic valve thrombosis and surgery should be reserved for those patients who fail to respond to thrombolytic therapy.

Adolescent↗
PubMedDate not supplied

Post-cardiotomy intra-aortic balloon counter pulsation: application and prognostic evaluation.

Cardiac assistance by intra-aortic balloon counter pulsation was studied in 113 cardiac surgical cases comprising 91 male and 22 female patients. This included 82 percent of patients having coronary artery bypass surgery, while 18 percent were operated for valvular lesions. It was observed that the time of institution of cardiac assistance by intra-aortic balloon counter pulsation, following cardiac surgery, was of prime importance to decrease patient mortality. It was lowest (16%) when the balloon was inserted for assistance before termination and highest (50%) when there was delay of more than 15 minutes following termination of cardiopulmonary bypass. Early balloon assistance significantly lowered the pulmonary capillary wedge pressure and usually 1:2 augmentation was more effective, probably because of existing tachycardia in most patients. Advances in catheter technology have reduced the vascular complication at the insertion site. Percutaneous insertion had less local complications (13.3%) than open arteriotomy technique (31.2%). Similarly with sheathless insertion, complications were less (6.6%) in comparison to sheathed insertion (21.7%). Proper placement of balloon avoided position-related complications and there was no compromise of blood flow through left internal mammary artery as noticed in our series.

Adolescent↗