PubMed Health⌕ Search

Biomedical subjects

S Nijhawan

Publications and source records attributed to S Nijhawan.

At least 19 recordsLinked to original sources

Magnetic loop basket: a "two-in-one" instrument.

BACKGROUND AND STUDY AIMS: Ingested coins are the most common foreign bodies encountered in the upper gastrointestinal tract in India and if they remain in the stomach for more than 5 days they need to be removed. Ferromagnetic retrieval instruments only work if the coins are ferromagnetic; and it is difficult to maneuver a loop basket in the fundus of the stomach. A magnetic loop basket was designed in an effort to overcome these difficulties and we assessed its feasibility, safety, and effectiveness in the removal of coins from the fundus of the stomach. PATIENTS AND METHODS: Twenty patients with a history of ingested coins were scheduled for removal of the coins using the magnetic loop basket. The time taken, complications, and failure rates were recorded. RESULTS: Twelve ferromagnetic coins were removed in a mean time of 60 seconds (range 30 - 90 seconds) and eight non-ferromagnetic coins were removed in a mean time of 150 seconds (range 90 - 180 seconds) without any failures or complications. CONCLUSION: The magnetic loop basket is a safe, effective, and quick method for removing both ferromagnetic and non-ferromagnetic metallic coins.

Equipment Design↗

Effect of esophageal and gastric distention on bronchial hyper-responsiveness in patients with bronchial asthma.

OBJECTIVE: Over-eating is said to aggravate asthma though the mechanism is still unclear. We tried to study the mechanism by causing distention in oesophagus and stomach. METHODS: Fifteen patients with nocturnal asthma were studied in a random cross-over design. The esophagus and stomach of the subjects were distended with a balloon. The effect of the distention on the airways was measured by taking forced expiratory volume one second (FEV1), forced vital capacity (FVC) and bronchial hyper-responsiveness (BHR). RESULTS: Distention of stomach caused significant reduction in FEV1 on FEV1/FVC ratio but similar distention of esophagus did not. Histamine PD20 was decreased by 0.43 (SEM 0.28) doubling dose with gastric distention. However, with oesophageal distention no significant change was observed in PD20. CONCLUSION: It can be concluded that gastric distention leads to broncho-constriction as measured by FEV1, FEV1/FVC ratio along with increase in BHR probably by inducing airway inflammation. Therefore asthmatic patients should be advised to avoid large meals.

Adolescent↗

Effect of intraesophageal acid instillation on airway reactivity in patients with asthma.

OBJECTIVE: To study the change in airway reactivity due to presence of acid in lower esophagus and its reversibility by antacid. METHOD: In this double blind study 12 subjects with asthma and gastroesophageal reflux received acid (N/10 hydrochloric acid) and antacid (mixture of magnesium trisilicate and aluminum hydroxide) perfusion in lower esophagus via a nasogastric tube. The four combinations were antacid-antacid (control), antacid-acid, acid-antacid and acid-acid. Airway reactivity (Histamine PD20) was recorded after each perfusion. RESULTS: Histamine PD20 significantly decreased (airway reactivity increased) (p < 0.05) with all three combinations containing acid as compared to control. No significant difference in airway reactivity was observed if the antacid was given before or after the acid. CONCLUSION: Presence of acid in lower esophagus can increase airway reactivity. This effect lasts longer than the presence of acid in esophagus itself.

Adolescent↗

Fulminant hepatitis in a tropical population: clinical course, cause, and early predictors of outcome.

The profiles of patients with fulminant hepatic failure (FHF) from developing countries have not been reported earlier. The current study was conducted prospectively, at a single tertiary care center in India, to document the demographic and clinical characteristics, natural course, and causative profile of patients with FHF as well as to define simple prognostic markers in these patients. Four hundred twenty-three consecutive patients with FHF admitted from January 1987 to June 1993 were included in the study. Each patient's serum was tested for various hepatotropic viruses. Univariate Cox's regression for 28 variables, multivariate Cox's proportional hazard regression, stepwise logistic regression, and Kaplan-Meier survival analysis were done to identify independent predictors of outcome at admission. All patients presented with encephalopathy within 4 weeks of onset of symptoms. Hepatotropic viruses were the likely cause in most of these patients. Hepatitis A (HAV), hepatitis B (HBV), hepatitis D (HDV) viruses, and antitubercular drugs could be implicated as the cause of FHF in 1.7% (n= 7), 28% (n= 117), 3.8% (n= 16), and 4.5% (n= 19) patients, respectively. In the remaining 62% (n= 264) of patients the serological evidence of HAV, HBV, or HDV infection was lacking, and none of them had ingested hepatotoxins. FHF was presumed to be caused by non-A, non-B virus(es) infection. Sera of 50 patients from the latter group were tested for hepatitis E virus (HEV) RNA and HCV RNA. In 31 (62%), HEV could be implicated as the causative agent, and isolated HCV RNA could be detected in 7 (19%). Two hundred eighty eight (66%) patients died. Approximately 75% of those who died did so within 72 hours of hospitalisation. One quarter of the female patients with FHF were pregnant. Mortality among pregnant females, nonpregnant females, and male patients with FHF was similar (P > .1). Univariate analysis showed that age, size of the liver assessed by percussion, grade of coma, presence of clinical features of cerebral edema, presence of infection, serum bilirubin, and prothrombin time prolongation over controls at admission were related to survival (P < .01). The rapidity of onset of encephalopathy and cause of FHF did not influence the outcome. Cox's proportional hazard regression showed age > or = 40 years, presence of cerebral edema, serum bilirubin > or = 15 mg/dL, and prothrombin time prolongation of 25 seconds or more over controls were independent predictors of outcome. Ninety-three percent of the patients with three or more of the above prognostic markers died. The sensitivity, specificity, positive predictive value, and the negative predictive value of the presence of three or more of these prognostic factors for mortality was 93%, 80%, 86%, and 89.5%, respectively, with a diagnostic accuracy of 87.3%. We conclude that most of our patients with FHF might have been caused by hepatotropic viral infection, and non-A, non-B virus(es) seems to be the dominant hepatotropic viral infection among these patients. They presented with encephalopathy within 4 weeks of the onset of symptoms. Pregnancy, cause, and rapidity of onset of encephalopathy did not influence survival. The prognostic model developed in the current study is simple and can be performed at admission.

Adolescent↗