The effect of local anesthetic continuous wound infusion for the prevention of postoperative pneumonia after on-pump cardiac surgery with sternotomy: the STERNOCAT randomized clinical trial

Abstract

Postoperative pain after cardiac surgery, exacerbated by cough and sternal mobilization, limits clearance of bronchopulmonary secretions and may predispose to postoperative pneumonia. In this study, we tested the ability of local anesthetic continuous wound infusion to prevent pneumonia after cardiac surgery with sternotomy and cardiopulmonary bypass (CPB) owing to better analgesia and bronchopulmonary drainage. Methods: In this randomized, double-blind, placebo-controlled trial conducted in five academic centers, patients undergoing cardiac surgery with sternotomy and CPB were enrolled from February 2012 until November 2014, and were followed over 30 days. Patients were assigned to a 48-h infusion (10 ml h −1) of l-bupivacaine (12.5 mg h −1) or placebo (saline) via a pre-sternal multiperforated catheter. Anesthesia and analgesia protocols were standardized. The primary end point was the incidence of pneumonia during the study period, i.e., until hospital discharge or 30 days. We hypothesized a 30% reduction in the incidence of pneumonia. Results: Among 1493 randomized patients, 1439 completed the trial. Pneumonia occurred in 36/746 patients (4.9%) in the l-bupivacaine group and in 42/739 patients (5.7%) in the placebo group (absolute risk difference taking into account center and baseline risk of postoperative pneumonia, − 1.3% [95% CI − 3.4; 0.8] P = 0.22). In the predefined subgroup of patients at high risk, l-bupivacaine decreased the incidence of pneumonia (absolute risk difference, − 5.6% [95% CI − 10.0; − 1.1], P = 0.01).

Predictive risk factors for postoperative pneumonia after heart transplantation

“…Overall, 56 patients (32%) were assisted with VA-ECMO until the HTx and were transplanted in salvage conditions, 25 patients (14.2%) were assisted with mechanical circulatory support (MCS) and 15 patients (8.6%) were assisted with mechanical ventilation ( Table 1). In the postoperative period, 114 (65.5%) primary graft dysfunctions occurred, requiring VA-ECMO support for 5 [4][5][6][7][8] days. The median mechanical ventilation duration was 2 [1][2][3][4][5][6][7] days.…”

“…Nosocomial infections, especially ventilator-associated pneumonia, are frequent in patients assisted by VA-ECMO [18], and HTx recipients assisted by VA-ECMO are known to develop nosocomial infections and pneumonia [10]. Moreover, the low cardiac output syndrome may explain the increased incidence of POP after HTx in comparison with conventional cardiac surgery (33.7% vs 5.7%), in which the incidence of intraand postoperative haemodynamic instability is less important [4]. In our cohort, a large proportion of recipients presented risk factors for primary graft dysfunction, such as allosensitization (54%), preoperative VA-ECMO support (32%) or mechanical ventilation at the time of transplantation (9%) [19][20][21].…”

“…The presence of Candida was considered pathological only if it was associated with lung abscesses. A POP diagnosis was retrospectively confirmed by 2 independent investigators (CV, RP) following analysis of the complete medical file, as previously reported [4]. Recurrent pneumonia was defined by the recurrence of clinical and paraclinical criteria of POP after the improvement of the first POP symptoms with an appropriate antibiotic therapy.…”

“…POP was defined as pneumonia occurring between the transplantation and hospital discharge and was the combination of clinical criteria (≥ two criteria including fever > 38.5°C, hyperleukocytosis > 10 9 ·L − 1 or leucopoenia < 4·10 8 ·L − 1 , occurrence of purulent secretions and occurrence or persistence of a radiological focus) and microbiological criteria with a positive quantitative culture obtained by bronchial aspiration (threshold ≥10 6 CFU·mL − 1 ), bronchoalveolar lavage (threshold ≥10 4 CFU·mL − 1 ) or protected distal sampling (PDP, threshold ≥10 3 CFU·mL − 1 ) [4,15]. The diagnosis of herpes virus pneumonia was based on the presence of more than 10, 000 copies·mL − 1 of the virus and evidence of a cytopathogenic effect on the anatomopathological investigation obtained by the bronchoalveolar lavage.…”

“…Thus, during the first year following HTx, postoperative infections represent the main cause of death in HTx recipients [3]. In cardiac surgery, POP is still the most common infectious complication [4] and is known to be associated with increased mortality [5,6]. After HTx, the incidence and risk factors for POP remain poorly investigated [7][8][9][10].…”