Delivery of Gaseous Nitric Oxide to the Extracorporeal Circulation Circuit: Experimental and Clinical Data: a review

Abstract

Introduction. Usually, gaseous nitric oxide (NO) is supplied to the patient by inhalation, adding to the inhaled gas mixture during spontaneous breathing, or supplying it to the inspiratory part of the ventilator. It is believed that the main point of its action is the pulmonary vasculature, where it exhibits an expanding effect, thus improving the oxygenation of arterial blood and reducing the pulmonary artery pressure. However, data from recent experimental clinical studies suggest that the addition of NO directly to the gas mixture supplied to the oxygenator makes it possible to systemically deliver NO into the bloodstream and, thereby, reduce the inflammatory response of the whole body caused by the extracorporeal circuit (cardiopulmonary bypass [CPB] or extracorporeal membrane oxygenation [ECMO]). Materials and methods. The search for publications was carried out in electronic databases PubMed, EMBASE. The last search term was December 30, 2020. The search term included the following words: “nitric oxide” and “artificial circulation” or “ECMO”. Only experimental and clinical randomized controlled blinded studies were selected for inclusion in the review. Results. The article analyzes data from recent studies related to the delivery of gaseous NO to the extracorporeal circuit, among which the issues of both NO delivery into the cardiopulmonary bypass line and the systemic and organ effects of nitric oxide delivered to the circuit are considered. The cardioprotective and anti-inflammatory effects of NO supplied to the extracorporeal circulation are considered in detail, as well as its effect on the lungs and kidneys. Conclusions. Further new randomized trials are needed to determine the place of the technology for supplying gaseous nitric oxide to the line of heart-lung machines or ECMO in modern cardiac surgery.