Linearization of the relationship between serum sodium, potassium concentration, their ratio and time since death in Chandigarh zone of north-west India.

A strong relationship was established between the ratio of postmortem serum sodium and potassium concentrations and time since death by Querido in wistar rats. Henceforth, the present study was carried out to substantiate this inclination in humans. Flame photometric estimation of sodium and potassium concentration in postmortem blood of 474 subjects revealed a highly significant relationship between logarithm serum sodium as well as potassium concentration, logarithm of their ratio and the logarithim of the time since death during the first 3-58 h of death. Nonetheless, postmortem interval can be predicted from alteration in postmortem serum sodium, potassium concentration and from their ratio with S.E. estimate of 3.2, 5.7 and 4.6 h, respectively but environmental temperature and cause of death modulate these changes significantly.