ACUTE LUNG INJURY IN FULMINANT HEPATIC-FAILURE FOLLOWING PARACETAMOL POISONING

Background - There is little information on the incidence of acute lun g injury or changes in the pulmonary circulation in acute liver failur e. The aim of this study was to record the incidence of acute lung inj ury in fulminant hepatic failure caused by paracetamol poisoning, to d ocument the associated pulmonary circulatory changes, and to assess th e impact of lung injury on patient outcome. Methods - The degree of lu ng injury was retrospectively assessed by a standard scoring system (m odified from Murray) in ah patients with fulminant hepatic failure cau sed by paracetamol poisoning, admitted to the intensive care unit over a one year period. The severity of liver failure and illness, other o rgan system failure, and patient outcome were also analysed. Results - Twenty four patients with paracetamol-induced liver failure were admi tted and nine developed lung injury of whom eight (33%) had severe inj ury (Murray score >2.5). In two patients hypoxaemia contributed to dea th. Patients with lung injury had higher median encephalopathy grades (4 v 2 in the noninjured group) and APACHE II scores (29 v 16). Circul atory failure, requiring vasoconstrictor support, occurred in all pati ents with lung injury but in only 40% of those without. Cerebral oedem a, as detected by abnormal rises in intracranial pressure, also occurr ed in all patients with lung injury but in only 27% of the noninjured patients. The incidence of renal failure requiring renal replacement t herapy was similar in both groups (67% and 47%). Pulmonary artery occl usion pressures were normal in the lung injury group. Cardiac output w as high (median 11.2 l/min), systemic vascular resistance low (median 503 dynes/s/cm(-5)), and pulmonary vascular resistance low (median 70 dynes/s/cm(-5)), but not significantly different from the group withou t lung injury. Mortality was much higher in the lung injury group than in the non-injured group (89% v 13%). Conclusions - Acute lung injury was common in patients with paracetamol-induced fulminant hepatic fai lure and was associated with systemic circulatory failure and cerebral oedema. The development of acute lung injury was associated with high mortality.