Surgical Treatment for Chronic Pulmonary Thromboembolism Under Cardiopulmonary Bypass with Selective Cerebral Perfusion

Abstract

The median sternotomy approach for the treatment of chronic pulmonary thromboembolism was recently improved by Daily, Jamieson, and coworkers who adopted it for use under cardiopulmonary bypass with intermittent circulatory arrest; however, we have sometimes found that the circulatory arrest time was too short to complete thromboendarterectomy. Therefore, we attempted to perform a selective cerebral perfusion technique to extend the endarterectomy time. Although we noted slight back-bleeding from the bronchial arteries, we were able to extend the endarterectomy time without causing any postoperative delirium. We conclude that the median sternotomy approach using cardiopulmonary bypass with selective cerebral perfusion may be the best option for extending the thromboendarterectomy time.

Antegrade Brain Perfusion for Pulmonary Thromboendarterectomy

“…The first two groups reported having to resort to DHCA in certain cases to complete the procedure due to significant bronchial artery backflow [2,5]. The third group reported having performed suboptimal dissections in 2 of their 4 cases [6]. We believe that clamping the origins of the left carotid artery and the right innominate artery is the best way to minimize retrograde backflow.…”

“…The Thomson et al group used continuous antegrade cerebral perfusion also via an ascending aortic cannula at 20˚C, with occasional clamping of the ascending aorta, proximally, and the region between the left common carotid and left subclavian artery distally [2]. Masuda et al, used bilateral perfusion of the right axillary and left common carotid artery, with clamping of the ascending aorta, at deep hypothermia (18˚C) [6]. The first two groups reported having to resort to DHCA in certain cases to complete the procedure due to significant bronchial artery backflow [2,5].…”

“…To enable an increase in circulatory arrest time and alleviate the need for deep hypothermia, there have been attempts by several groups to use antegrade cerebral brain perfusion to improve operative morbidity in PTE [2,5,6]. The concept of antegrade cerebral brain perfusion had previously been successfully implemented in aortic arch surgery [7].…”

Pulmonary endarterectomy

“…Too deep a dissection may lead to pulmonary artery perforation and haemorrhage; too shallow may mean that inadequate amounts of the thromboembolic material are removed and PHT may persist [33 ]. In some centres, selective antegrade cerebral perfusion is preferred and this will often allow adequate visualization; the aorta is cross-clamped just proximal to the left subclavian artery and also below the aortic cannula in the ascending portion [34]. This allows circulatory flow to the brain at a reduced level (1-1.5 l/min), which can be monitored via the right radial artery (pressure of 30-40 mmHg) and compared with the femoral artery (pressure of 0-10 mmHg).…”

Pulmonary thromboendarterectomy for chronic thromboembolic pulmonary hypertension

“…10,20 Others perform selective antegrade cerebral perfusion to be able to extend the endarterectomy time, and avoid postoperative delirium. 25,31 Circulatory arrest time is limited to 20 min. If the endarterectomy cannot be performed within this period, then hypothermic reperfusion is performed for at least 10 min, or venous saturation is allowed to return to at least 90%.…”