Pulmonary thromboembolism in liver transplantation: a retrospective review of the first 25 years

Abstract

The evidence on the state of 'haemostasis' at the time of liver transplantation (LT) is conflicting, with recent publications that suggest a hypercoagulable state, in contrast to traditionally held views. These findings raise the issue of thrombo-embolic complications after LT, an area of interest which has received little attention in recent published literature. We therefore conducted a retrospective review of our experience of 3000 liver transplants over 25 years. Our prospective transplant database was reviewed to find all patients who were suspected to have had a pulmonary embolism (PE) during or following LT. Paediatric transplants were excluded. A part of this database was cross referenced against hospital records to corroborate its accuracy. Clinical records of all these patients were reviewed and relevant aspects collated and analyzed. Following exclusion of the paediatric recipients, 2 149 adults were reviewed to find 36 patients in whom a PE was suspected (median age 49), 21 of whom were within 90 days of transplant (median duration 22 days). PE was ruled out in 10, unconfirmed in two, confirmed in eight patients; and in one, air embolism was found. All PEs occurred in hospital, but aetiology of liver failure was varied. Of note, two patients died of an on-table PE and one patient of chronic rejection/disease recurrence (Primary Sclerosing Cholangitis). The remaining five are still alive (median survival of 65 months). Although thromboprophylaxis is now routine in our unit, its use in these patients could not be confirmed from records available. Fifteen PE were suspected and confirmed after 90 days from transplant (six within, and nine out with the first year). Acute PE in the setting of LT has an incidence rate in our series of 0.37% that would appear to be lower than previously reported and lower than one would expect after a 'major complex' category operation. This potentially suggests that the overall haemostatic function in these patients is still weighted towards hypocoagulation with the resultant risk of excessive bleeding. Aetiology of liver disease did not seem to confer a higher risk in our series. The prognosis after post-operative PE appears good although sudden death due to an on-table embolism is a rare but significant risk.