title: Review of investigation and management of severe hyponatraemia in a hospital population.
abstract: The purpose of this study was to assess retrospectively the prevalence of severe hyponatraemia in a hospital population and its laboratory investigation, treatment and clinical outcome. Over a 6-month period 47 patients (27 women and 20 men) were found to have a plasma sodium concentration of < or = 120 mmol/L (this number made up less than 0.17% of all plasma sodium requests over that time period). The mean patient age was 75 +/- 16 years and the average hospital stay was 37 +/- 45 days (1-179 days). Patient mortality was 51% (women 57% and men 43%). The mean initial plasma sodium concentration was 116 +/- 4.5 mmol/L, rising after therapeutic intervention to a mean of 130 +/- 4.2 mmol/L. The mean plasma sodium correction rate was 4.7 +/- 4.3 mmol/L/24 h (0.9-17.5 range). Twelve per cent of the patients had their plasma sodium raised at a rate of greater than 10 mmol/L/24 h after their initial presentation. Two patients may have had symptoms and signs suggestive of cerebral oedema/cortical dysfunction: in one patient the sodium concentration was raised at a rate of 9.5 mmol/L/24 h and in the other at 12.0 mmol/L/24 h. Sixty-one per cent of the patients had a chest infection, 44% were on diuretics, 28% had congestive cardiac failure, 28% were post-operative (9% orthopaedic procedures), 19% had carcinoma and 9% were on a selective serotonin re-uptake inhibitor. Regarding laboratory investigations, 56% had liver function tests, 41% had thyroid function tests, 36% had plasma osmolality determination, 36% had urinary electrolytes including urinary osmolality and < 2% had tests to exclude hypoadrenalism.
authors.affiliation: Department of Chemical Pathology, University Hospital Lewisham, London, UK.
authors.forename: M A
authors.initials: MA
authors.lastname: Crook
authors.forename: U
authors.initials: U
authors.lastname: Velauthar
authors.forename: L
authors.initials: L
authors.lastname: Moran
authors.forename: W
authors.initials: W
authors.lastname: Griffiths
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D005260:Female; D006760:Hospitalization; D006801:Humans; D007010:Hyponatremia / Q000097:blood / Q000175:diagnosis / Q000628:therapy* / Q000652:urine; D007223:Infant; D008297:Male; D008875:Middle Aged; D012964:Sodium / Q000097:blood
chemical_list: D012964:Sodium