Jyoti Prakash, K. K. Singh

BACKGROUND Hyponatremia is the most common electrolyte imbalance encountered in hospitalized patients worldwide. Our study is designed to analyse aetiology, clinical presentations, associated co-morbidities, severity, rate of correction and clinical outcome of hyponatremia in diverse group of patients in ICU. The aim of the study was to evaluate the prevalence, aetiology, clinical features and effect of various factors on the outcome of hyponatremia in patients admitted in ICU. MATERIALS AND METHODS All indoor general medicine admissions in the department of medicine, Darbhanga Medical College, Laheriasarai, Bihar during Feb. 2017 to Feb. 2018 were screened for hyponatremia and patients requiring ICU care were studied. RESULTS In our study, 6% of total admission had hyponatremia. Hyponatraemic patients admitted in ICU showed varied clinical presentation such as nausea (70%), malaise (88%), drowsiness (38%), lethargy (62%), confusion (32%), altered sensorium (44%) and convulsion (4%). Average serum Na was 122 meq/L, average serum osmolality was 268 mosm/L, average Hb was 10.6 gm/dl. 33% patients had raised serum creatinine (>1.4 mg/dl). Lower GCS was associated with a significantly lower survival (p value = 0.004). There was no significant association between serum Na on admission and the duration of hospital stay (p value= 0.06). Overall mortality was 18/50 (36%) which was quite significant as compared to total ICU mortality (30%). Most of the mortality was due to sub-optimal correction of Na. CONCLUSION Hyponatremia is quite a common electrolyte disorder encountered in ICU setting. Most common cause is SIADH. Hyponatraemic patients who presented with altered sensorium had poor outcomes. Type of fluid used for correction had not so much influence over the outcome. Under correction of hyponatremia in first 24 hour had poorer outcome whereas overcorrection had no any survival benefit, rather it was associated with risk of CPM.