PULMONARY AND SERUM SURFACTANT PHOSPHOLIPIDS AND SERUM CATECHOLAMINESIN STRANGULATION - AN EXPERIMENTAL-STUDY ON RATS

Elevations of phospholipid and catecholamine concentrations in the blo od are regarded as the vital reactions in asphyxial deaths, which leav e few or no morphological signs in the body. These vital reactions wer e tested here, under strict experimental conditions, employing rapid a sphyxia. Rats anaesthetized with barbiturate were strangled with a rop e 2 mm thick tightened with a force of 29.4 N (3 kp). The main surfact ant components, phosphatidyl choline and phosphatidyl ethanol amine, w ere measured in serum and lung samples, and catecholamines in the seru m. The lungs were also investigated histologically. The serum phosphol ipid concentration in the strangulated rats was 1.36+/-0.32 g/l, versu s 1.04+/-0.17 g/l in the controls (barbiturate intoxication), P<0.001, but no change in their content was observed in the lungs (26.21+/-4.0 4 mg/g vs. 25.15+/-3.64 mg/g dry weight). Histologically, focal emphys ema and tiny haemorrhages were seen in the lungs of both groups with s imilar frequency. Mean serum noradrenaline (NA) and adrenaline (A) con centrations were significantly higher in the strangulation group (NA=5 .4+/-2.6 ng/ml vs. 2.8+/-0.1 ng/ml, P<0.001 and A=6.0+/-3.4 ng/ml vs. 3.8+/-3.0 ng/ml, P<0.05). The results support the notion that phosphol ipid and catecholamine concentrations are increased in the blood upon suffocation and could thus be taken as indicators of hypoxia. Further investigations into postmortem phospholipid change or stability are ne eded. There are reports that phospholipid concentration remain quite s table for two days post mortem, whereas catecholamine concentrations t end to rise quite soon after death. (C) 1997 Elsevier Science Ireland Ltd.