Strategies to prevent intraoperative lung injury during cardiopulmonary bypass

Abstract

During open heart surgery the influence of a series of factors such as cardiopulmonary bypass (CPB), hypothermia, operation and anaesthesia, as well as medication and transfusion can cause a diffuse trauma in the lungs. This injury leads mostly to a postoperative interstitial pulmonary oedema and abnormal gas exchange. Substantial improvements in all of the above mentioned factors may lead to a better lung function postoperatively. By avoiding CPB, reducing its time, or by minimizing the extracorporeal surface area with the use of miniaturized circuits of CPB, beneficial effects on lung function are reported. In addition, replacement of circuit surface with biocompatible surfaces like heparin-coated, and material-independent sources of blood activation, a better postoperative lung function is observed. Meticulous myocardial protection by using hypothermia and cardioplegia methods during ischemia and reperfusion remain one of the cornerstones of postoperative lung function. The partial restoration of pulmonary artery perfusion during CPB possibly contributes to prevent pulmonary ischemia and lung dysfunction. Using medication such as corticosteroids and aprotinin, which protect the lungs during CPB, and leukocyte depletion filters for operations expected to exceed 90 minutes in CPB-time appear to be protective against the toxic impact of CPB in the lungs. The newer methods of ultrafiltration used to scavenge pro-inflammatory factors seem to be protective for the lung function. In a similar way, reducing the use of cardiotomy suction device, as well as the contact-time between free blood and pericardium, it is expected that the postoperative lung function will be improved.

Transplantation techniques for the resection of renal cell carcinoma with tumor thrombus: A technical description and review

“…In most cases, the approach described above avoids the need for a sternotomy and CPB [9,24], the latter associated with diffuse lung injury [25], postoperative coagulopathy [26], and neurologic sequelae [27]. However, in selected cases of patients with adherent intra-atrial thrombus, CPB may be required.…”

Clinical Strategies to Prevent Pulmonary Complications in Cardiac Surgery: An Overview

“…Direct blood contact with artificial surfaces of the CPB system activates leukocyte and cytokine release. 9 Nonpulsatility, ischemia, and reperfusion can activate this response as well. This inflammatory response leads to increased pulmonary vascular permeability and, thus, pulmonary edema with respiratory failure.…”

Are lung-protective ventilation strategies worth the effort?

“…65 While the incidence of ARDS post CBP is low (< 2%), the mortality associated with it is high (> 50%). 66 While the systemic inflammatory response syndrome that is initiated by CPB plays a major role, the pulmonary insult is multifactorial and does not relate to the bypass itself.…”