Complications of sonographically assisted liver biopsies in dogs and cats

Objective: Ultrasound-guided biopsies are obtained generally to reach a sound diagnosis in the case of sonographically detectable hepatic changes. The most common and well-known complication associated with ultrasound-guided biopsies is haemorrhage after sampling, which may lead to the patient's death. The aim of this study was to evaluate a possible association between alterations in the coagulation parameters and sonographically observable haemorrhage following liver biopsies. Materials and methods: Dogs and cats in which an ultrasound-guided biopsy of the liver had been performed were retrospectively enrolled in the study. Inclusion criteria were thoroughly documented sonographic findings and the results of the coagulation parameter thromboplastin time or a combination of the activated partial thromboplastin time and prothrombin time. The incidence of post-interventional ascites and possible risk factors were evaluated. Results: A total of 105 patients met the inclusion criteria and the data of 94 dogs (89.5 %) and 11 cats (10.5 %) were analysed. Post-interventional complications occurred in 26 of 105 patients (24.8 %), 21.9 % being minor and 2.9 % being major. Free abdominal fluid after intervention was sonographically detected in 22 of 94 dogs (23.4 %) and four of 11 cats (36.4 %). Three of 10 dogs (2.9 %) with a clinically significant prolongated coagulation time of > 25 % had ascites after biopsy. Only a small amount of fluid was detected in two of these three dogs, while a moderate amount of ascites was observed in the third dog. One of two cats with a prolonged coagulation time of > 25 % developed a moderate amount of ascites after the puncture. No statistically significant association was found between the occurrence of post-interventional ascites and a prolongation of the coagulation time. Conclusion: According to the study results, there is no obvious correlation between alterations in coagulation and haemorrhage after an ultrasound-guided liver biopsy.