Inhaled Nitric Oxide ReDuce postoperatIve pulmoNAry complicaTions in patiEnts with recent COVID-19 infection (INORDINATE): protocol for a randomised controlled trial.

BACKGROUND: A history of SARS-CoV-2 infection has been reported to be associated with an increased risk of postoperative pulmonary complications (PPCs). Even mild PPCs can elevate the rates of early postoperative mortality, intensive care unit (ICU) admission and prolong the length of ICU and/or hospital stays. Consequently, it is crucial to develop perioperative management strategies that can mitigate these increased risks in surgical patients who have recently been infected with SARS-CoV-2. Accumulating evidence suggests that nitric oxide (NO) inhalation might be effective in treating COVID-19. NO functions in COVID-19 by promoting vasodilation, anticoagulation, anti-inflammatory and antiviral effects. Therefore, our study hypothesises that the perioperative use of NO can effectively reduce PPCs in patients with recent SARS-CoV-2 infection.

METHOD AND ANALYSIS: A prospective, double-blind, single-centre, randomised controlled trial is proposed. The trial aims to include participants who are planning to undergo surgery with general anaesthesia and have been recently infected with SARS-CoV-2 (within 7 weeks). Stratified allocation of eligible patients will be performed at a 1:1 ratio based on the predicted risk of PPCs using the Assess Respiratory Risk in Surgical Patients in Catalonia risk index and the time interval between infection and surgery.The primary outcome of the study will be the presence of PPCs within the first 7 days following surgery, including respiratory infection, respiratory failure, pleural effusion, atelectasis, pneumothorax, bronchospasm and aspiration pneumonitis. The primary outcome will be reported as counts (percentage) and will be compared using a two-proportion χ2 test. The common effect across all primary components will be estimated using a multiple generalised linear model.

ETHICS AND DISSEMINATION: The trial is approved by the Institutional Review Board of Xijing Hospital (KY20232058-F1). The findings, including positive, negative and inconclusive results, will be published in scientific journals with peer-review processes.

TRIAL REGISTRATION NUMBER: NCT05721144.