The feasibility of selective left lower lobar blockade based on Coopdech endobronchial blocker tube

Abstract

Objective To observe the feasibility of selective left lower lobar blockade by Coopdech endobronchial blocker tube (BB)in patients with normal spirometry during left-sided lower esophageal surgery, and the effects on dynamic lung compliance (Cdyn), peak inspiratory airway pressure(Ppeak)and arterial oxygenation. Methods 30 patients(aged 44-64 yr)scheduled for left-sided lower esophageal surgery were allocated randomly to two groups: Group BB or group double-lumen endobronchial tubes (DLT)(n=15). Anesthesia was induced and maintained with Propofol by target controlled infusion, administered sufentanil and cisatracurium intravenously if needed. The left-sided DLT was placed in the DLT group and an 8.0-mm internal diameter single-lumen endotracheal tube was used in the BB group and 9 French Coopdech blocker was advanced into the left lower lobar bronchus with the guidance of a fiberoptic bronchoscope in the latter group. The variables recorded were Ppeak, Cdyn and arterial blood gas analyses data at four surgical times: 20 minutes after two-lung ventilation in supine position (T_1), 20 minutes after initiation of one-lung ventilation or selective left lower lobar blockade by inflating BB balloons in right lateral decubitus position (T_2), total collapse of left lung or left lower lobe after the pleura was opened(T_3) and before tracheal extubation(T_4). Tidal volume and respiratory rate were kept constant at each time. Once the pleura were opened, the effectiveness of lung collapse was evaluated by the surgeon who performed the surgery. Chest radiograph and arterial blood gas analyses were performed in the first postoperative day. Results The groups were comparable with regard to rank of surgical exposure; pH, PaCO_2 from T_1 to T_4; Cdyn, Ppeak, PaO_2 at T_1. Significant trends were found toward a higher decrease in Ppeak [ (17.7±2.9) cm H_2O vs (21.7±3.6) cm H_2O in T_2, (17.8±3,2) cm H_2O vs (22.6±2.6) cm H_2O in T_3,(14.8±2.2) cm H_2O vs(16.8±1.8) cm H_2O in T_4, respectively] and a better improvement in cdyn[ (36±9) ml/cm H_2O vs (24±6) ml/cm H_2O in T_2, (37±10) ml/cm H_2O vs (23±6) ml/cm H_2O in T_3, (44±8) ml/cm H_2O vs (35±12) ml/cm H_2O in T_4, respectively], PaO_2[ (220±56) mm Hg vs (146±38) mm Hg in T_2, (188±57) mm Hg vs (140±36) mm Hg in T_3, (208±24) mm Hg vs(157±33) mm Hg in T_4, respectively] during the operation with the BB compared to DLT (P<0.05 or <0.01). No lobe collapse was observed in the postoperative period in BB group, but 1 patients of DLT group was found left lower lobe atelectasis. A better postoperative arterial oxygenation was shown in BB group (P<0.01). Conclusion Selective left lower lobar blockade achieved by Coopdech endobronchial blocker tube during left-sided esophageal surgery provides a good surgical exposure, together with a lower intraoperative peak inspiratory airway pressure, and better arterial oxygenation and dynamic lung compliance. Key words: Selective lobar blockade; Endobronchial blocker tube; Double-lumen endobronchial tube; One lung ventilation; Dynamic lung compliance; Peak inspiratory airway pressure