[A single-center experience of venous thromboembolism after adult lung transplantation]

Objective: To investigate the incidence of venous thromboembolism (VTE) in lung transplant (LT) recipients. Methods: The clinical data on 124 consecutive patients who underwent lung transplant at Lung Transplantation Center of China-Japan Friendship Hospital from March 2017 to September 2018 were retrospectively collected. Deep venous thrombosis (DVT) was ascertained by vascular ultrasound. Pulmonary embolism (PE) was diagnosed by either chest computed tomography pulmonary angiogram or ventilation/perfusion scan. The risk factors in those patients with postoperative VTE were studied. Results: A total of 124 lung transplant recipients including 78 single lung transplant recipients (62.9%) and 46 bilateral lung transplant recipients(37.1%) were enrolled. Preoperative and postoperative prophylactic anticoagulant was used in 52 patients(52/124, 41.9%) and 69 patients(69/124, 55.6%) respectively. Thirty-two patients developed postoperative VTE among 124 consecutive patients. The overall incidence rate of VTE among 124 LT recipients was 25.8%. The median time to VTE episode following lung transplant was 22.5 days (range 4-295 days). The percentage of DVT in VTE was 93.8%(30/32), involving 1-8 (2.83±1.86) veins. And 60.0% of DVT was from lower extremities and 56.7% located in upper extremities (P>0.05). Four patients (4/32,12.5%) had PE episodes, and half of them suffered from only PE without DVT. The use of extracorporeal membrane oxygenation (ECMO) in 32 patients with VTE was 90.6% (29/32), which was significantly higher than that without VTE (64/92,69.6%, P=0.033). However, there was no difference in the use of peripherally inserted central catheter (PICC) between two groups (96.9% vs 81.5%, P=0.067). Resolution of VTE was successfully accomplished by anticoagulant therapy with long-term use of low molecular weight heparin in 30 patients (93.7%) and followed by oral warfarin in 2 patients (6.3%). Three months follow-up data after anticoagulant therapy showed that total and partial vascular recanalization rate was 65.6%(21/32) and 34.4%(11/32), respectively. Despite anticoagulation-related bleeding complications in three patients, no serious consequences occurred. Conclusions: VTE was frequent in LT recipients. It was speculated that ECMO utilization may be a major risk factor for high incidence of VTE in LT recipients. Aggressive VTE screening/treatment protocols were suggested to be implemented in LT recipients.