Inhaled NO in Surgical Patients With Recent COVID-19 Infection

Study Overview
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Brief Summary
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The aim of this study is to evaluate the effect of perioperative inhalation of NO on reducing the incidence of postoperative pulmonary complications in patients with recent COVID-19 infection, and to evaluate whether inhaled NO can improve the prognosis of patients. The investigators will enroll 660 surgical patients who was infected with SARS-CoV-2 within 42days (7 weeks ) prior to planed surgery under general anesthesia. Patients will be randomized to receive either inhaled nitric oxide (per protocol) or a placebo. Perioperative standards of care will be the institution's own protocols (such as ventilation strategies and use and dose of anesthetics, analgesia and fluid management, etc).

Detailed Description
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The outbreak of COVID-19 and its global pandemic has posed a threat to public health. On December 7, 2022, the National Health Commission (NHC) of China issued an announcement on further optimization of public health control measures. Since then, the rapid spread and breakthrough of SARS-CoV-2 infections have been observed in the majority of China, caused by the more infectious and less virulent Omicron variant of SARS-Cov-2. Consequently, the proportion of surgical patients with current or previous SARS-CoV-2 infections will inevitably increase within a relatively narrow time window. It has been reported that a history of SARS-CoV-2 infection is associated with a transiently elevated risk of postoperative complications. The longer the time interval between infection and surgery, the lower the risk of postoperative complications. An updated recommendation suggested postponing surgery for at least seven weeks following SARS-CoV-2 infection, thereby reducing the risk of postoperative complications and 30-day mortality to baseline levels (similar to those without a history of SARS-CoV-2 infection). COVID-19 infection significantly affects respiratory functions by massively disrupting pulmonary oxygenation and activating the synthesis of proinflammatory cytokines, inducing severe oxidative stress, enhanced vascular permeability, and endothelial dysfunction which has rendered researchers and clinicians to depend on prophylactic treatment due to the unavailability of proper disease management approaches. Inhaled nitric oxide gas (NO) has shown antiviral activity against Coronavirus during the 2003 SARS outbreak. Previous studies have indicated that nitric oxide (NO) application appears to be significant concerning the antiviral activities, antioxidant, and anti-inflammatory properties in relieving disease-related symptoms. Inhaled nitric oxide had been widely used during the Covid-19 pandemic. In the scoping and systemic reviews, it was demonstrated that nitric oxide inhalation was effective in improving oxygenation, cardiopulmonary function, and fastening virus clearance. The investigators designed this study to assess whether inhaled NO reduces postoperative pulmonary complications in patients with a COVID-19 infection history 7 weeks prior to surgery. Here, the investigators propose a randomized clinical trial aimed to improve postoperative outcomes in patients with an increased risk of postoperative pulmonary complications after COVID-19 infection. Control group: the institutional standard of care will be delivered. Treatment group: In addition to standard therapy, the subjects will receive inhalation of NO. Inspired NO/N2 will be delivered at 80 parts per million (ppm) after anesthesia induction and intubation and last until the end of surgery and leave the operating room. The physician will follow their own institutional weaning protocols. In the absence of institutional protocols, NO will be reduced in a step-wise fashion starting from 40 ppm to 20, 10, 5, 3, 2, and 1 ppm. If hypoxemia (SpO2 < 93%) or acute hypotension (systolic blood pressure < 90 mmHg) occurs during weaning, NO should be increased to a prior higher concentration. Safety: prolonged treatment with inhaled NO can lead to increased methemoglobin levels. Blood levels of methemoglobin will be monitored via a non-invasive CO-oximeter or MetHb levels in the blood. If methemoglobin levels rise above 5% at any point in the study, inhaled NO concentration will be halved.

Official Title
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Inhaled NO ReDuce postoperatIve pulmoNAry complicATions in patiEnts With Recent COVID-19 Infection

Conditions
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COVID-19, Nitric Oxide, Surgery, Postoperative Complications

Intervention / Treatment
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* Drug: Nitric Oxide Gas


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: ≥ 18 years old Planned for surgery under general anesthesia With a history of COVID-19 infection within 7 weeks prior to surgery. Exclusion Criteria: Physician makes a decision that trial involvement is not in the patient's best interest or any condition that does not allow the protocol to be followed safely ASA ≥ IV, life expectancy< 24 h. Pregnant or lactating women. Severe liver disease (Child-Pugh score ≥ 12). Patients with severe respiratory failure need mechanical ventilation support or ECMO life support before the operation. Severe renal dysfunction (eGFRC≤30 ml/min/1.73m2) or receiving continuous renal replacement therapy, hemodialysis, and peritoneal dialysis. Having received or participated in other clinical trials within the previous month.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Experimental: Treatment Group<br>Inspired NO/N2 will be delivered at 80 parts per million (ppm) after anesthesia induction and intubation and lasted until the end of surgery and leave the operating room. The physician will follow their own institutional weaning protocols. | Drug: Nitric Oxide Gas<br>* Inspired NO/N2 will be delivered at 80 parts per million (ppm) after anesthesia induction and intubation and lasted until the end of surgery and leave the operating room.<br>* Other names: Nitric Oxide inhalation;|
| No Intervention: Sham Comparator: Control Group<br>The delivery system will be set up anyway without studying gas administration | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| postoperative pulmonary complications | It is composite outcome including respiratory infection, respiratory failure, pleural effusion, atelectasis, pneumothorax, bronchospasm, and aspiration pneumonitis | within 7 days after operation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| mortality within 30 days postoperatively | All-cause mortality | within 30 days after operation | 
| Classification of pulmonary complications (Clavien-Dindo) | Evaluation of the severity of pulmonary complications according to Clavien-Dindo classification. It consists of 7 grades (I, II, IIIa, IIIb, IVa, IVb and V). | within 7 days after operation | 
| the rate of unplanned ICU admission | Percentage of patients admitted into ICU after surgery, which is not expected before surgery | within 7 days after operation | 
| postoperative length of hospital stay | duration between end of surgery and discharge from hospital | From the date of surgery until the date patient discharge from hospital, assessed up to 30 days | 
| Incidence of thrombotic events | including DVT and pulmonary embolism | From the date of surgery until the date patient discharge from hospital, assessed up to 30 days | 
| incidence of nonpulmonary complications | including acute kidney injury, Stroke and myocardial infarction | From the date of surgery until the date patient discharge from hospital, assessed up to 30 days | 
| postoperative comprehensive complication index (CCI) | Ranging from 0 (no complication) to 100 (death) was computed based on the Clavien-Dindo classification | within 7 days after operation | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Surgery, Nitric Oxide Inhalation, Postoperative Pulmonary Complications, COVID-19