Nitroglycerin can facilitate weaning of difficult-to-wean chronic obstructive pulmonary disease patients: a prospective interventional non-randomized study

Abstract

IntroductionBoth experimental and clinical data give convincing evidence to acute cardiac dysfunction as the origin or a cofactor of weaning failure in patients with chronic obstructive pulmonary disease. Therefore, treatment targeting the cardiovascular system might help the heart to tolerate more effectively the critical period of weaning. This study aims to assess the hemodynamic, respiratory and clinical effects of nitroglycerin infusion in difficult-to-wean patients with severe chronic obstructive pulmonary disease.MethodsTwelve difficult-to-wean (failed ≥ 3 consecutive trials) chronic obstructive pulmonary disease patients, who presented systemic arterial hypertension (systolic blood pressure ≥ 140mmHg) during weaning failure and had systemic and pulmonary artery catheters in place, participated in this prospective, interventional, non-randomized clinical trial. Patients were studied in two consecutive days, i.e., the first day without (Control day) and the second day with (Study day) nitroglycerin continuous intravenous infusion starting at the beginning of the spontaneous breathing trial, and titrated to maintain normal systolic blood pressure. Hemodynamic, oxygenation and respiratory measurements were performed on mechanical ventilation, and during a 2-hour T-piece spontaneous breathing trial. Primary endpoint was hemodynamic and respiratory effects of nitroglycerin infusion. Secondary endpoint was spontaneous breathing trial and extubation outcome.ResultsCompared to mechanical ventilation, mean systemic arterial pressure, rate-pressure product, mean pulmonary arterial pressure, and pulmonary artery occlusion pressure increased [from (mean ± SD) 94 ± 14, 13708 ± 3166, 29.9 ± 4.8, and 14.8 ± 3.8 to 109 ± 20mmHg, 19856 ± 4877mmHg b/min, 41.6 ± 5.8mmHg, and 23.4 ± 7.4 mmHg, respectively], and mixed venous oxygen saturation decreased (from 75.7 ± 3.5 to 69.3 ± 7.5%) during failing trials on Control day, whereas they did not change on Study day. Venous admixture increased throughout the trial on both Control day and Study day, but this increase was lower on Study day. Whereas weaning failed in all patients on Control day, nitroglycerin administration on Study day enabled a successful spontaneous breathing trial and extubation in 92% and 88% of patients, respectively.ConclusionsIn this clinical setting, nitroglycerin infusion can expedite the weaning by restoring weaning-induced cardiovascular compromise.

New insights into weaning from mechanical ventilation: left ventricular diastolic dysfunction is a key player

“…Notably, it was recently reported that patients with diastolic dysfunction may present impaired diastolic reserve under stressful conditions [27], and this possibly explains weaning intolerance. In line with the above, other authors suggested that weaning outcomes may improve with the application of strategies aiming to manage heart failure (i.e., diuretics, nitroglycerin) [17,28,29]. In our cohort, we found that patients who failed weaning presented known precipitating factors for LV diastolic dysfunction (i.e., age, arterial hypertension, increased wall thickness and LV mass, and COPD) [30].…”

Survey of Prolonged Mechanical Ventilation in Intensive Care Units in Mainland China

“…Such increases may not be tolerated by patients with compromised heart function, which becomes the cause or a cofactor of weaning failure, 26 described as "weaning-induced cardiovascular compromise." 26,27 One limitation of our study was that we did not acquire more comprehensive information to decide whether subjects could be transferred out of the ICU or not. Additionally, we only followed the subjects for 28 d in the ICU, and we did not collect subject data on the 14th or 21st day of mechanical ventilation.…”

Ventilatory Strategies in Obstructive Lung Disease

“…In a nonrandomized study of difficult-to-wean COPD patients, the authors showed that nitroglycerin is well tolerated and may facilitate weaning due to its stabilizing effect on hemodynamics in these patients. 102 Other aspect to take into account is the method to carry out the spontaneous breathing trial. In this way, Cabello et al 103 compared three methods of performing weaning trials in 14 patients (7 of whom had COPD) who had previously failed a T-piece trial.…”