Incidence and Causes of Reintubation Other Than Reopening of the Chest in Post-Cardiac Surgical Patients in a Tertiary Care Hospital

Abstract

Objective To determine the incidence of endotracheal reintubation, excluding surgical reopening, in post-cardiac surgical patients in a tertiary care hospital. Material and methods A retrospective descriptive analysis of 408 patients who underwent different cardiac surgeries during this period. Post-operative extubation was performed when patients fulfilled the preset criteria for extubation, which include consciousness (awake and aware), stable vital signs, acceptable arterial blood gases, acceptable respiratory mechanics, a maximum inspiratory force greater than 20-25 cm H2O, chest tube drainage less than 100 ml per hour, normal temperature and electrolytes. The total number of patients who were reintubated within 72 hours of extubation was noted. The criteria for reintubation included altered conscious level with Glasgow Coma Score (GCS) of less than 8, respiratory failure, unstable hemodynamics, and arrhythmias such as ventricular tachycardia (VT) and fibrillation. All of the information was collected retrospectively on a specifically prepared form. Data was entered and evaluated in Statistical Package for the Social Sciences. The research was piloted in the Cardiac Intensive Care Unit (CICU) of Northwest General Hospital and Research Center, Hayatabad, Peshawar from December 2018 to March 2020. Results Out of 408 patients who had cardiac surgeries, only nine (2.2%) were reintubated after initial extubation. The average time for which patients remained on the ventilator was 8 ± 2 hours. The reasons for reintubation were recorded. Among those reintubated, eight patients (88.88%) had undergone coronary artery bypass grafting (CABG) whereas one patient (11.11%) had undergone mitral valve replacement (MVR). In three (33.33%) patients, stroke (hemiplegia in two and global brain ischemia in one) with low GCS was the primary cause of reintubation. Arrhythmias - which included VT, ventricular fibrillation (VF), and supraventricular tachyarrhythmias (SVT) - were responsible for three (33.33%) cases of reintubation. Respiratory failure - with a partial pressure of oxygen in arterial blood less than 60 mmHg, along with tachypnea - was responsible for reintubation in two (22.22%) patients. In one (11.11%) patient who had MVR, cardiac arrest was the underlying reason; the cause of arrest could not be retrieved from the retrospective data. Notably, as a common variable, five (62.5%) out of the eight reintubated CABG patients had a poor left ventricular function. Conclusion Causes of reintubation were primarily cardiac (arrhythmias) and neurological, followed by respiratory causes in our center. Patients with poor left ventricular function and diffuse coronary artery disease appear to have a higher incidence of reintubation which can lead to extended CICU and hospital stay, elevated mortality, and higher costs.