Predictors of extubation failure after open-chest cardiac surgery based on routinely collected data. The importance of a shared interprofessional clinical assessment

Background: Extubation failure (ExtF) is associated with prolonged hospital length of stay and mortality in adult cardiac surgery patients postoperatively. In this population, ExtF-related variables such as the arterial partial pressure of oxygen to fraction of inspired oxygen ratio (PaO2/FiO2), rapid shallow breathing index, cough strength, endotracheal secretions and neurological function have been sparsely researched. Aim: To identify variables that are predictive of ExtF and related outcomes. Method: Prospective observational longitudinal study. Consecutively presenting patients (n=205) undergoing open-heart cardiac surgery and admitted to the Cardiosurgical Intensive Care Unit (CICU) were recruited. The clinical data were collected at CICU admission and immediately prior to extubation. ExtF was defined as the need to restart invasive or non-invasive mechanical ventilation while the patient was in the CICU. Results: The ExtF incidence was 13%. ExtF related significantly to hospital mortality, CICU length of stay and total hospital length of stay. The risk of ExtF decreased significantly, by 93% in patients with good neurological function and by 83% in those with a Rapid Shallow Breathing Index of ≥57 breaths/min per litre. Conversely, ExtF risk increased 27 times when the PaO2/FiO2 was <150 and 11 times when it was ≥450. Also, a reassuring PaO2/FiO2 value may hide critical pulmonary or extra-pulmonary conditions independent from alveolar function. Conclusion: The decision to extubate patients should be taken after thoroughly discussing and combining the data derived from nursing and medical clinical assessments. Extubation should be delayed until the patient achieves safe respiratory, oxygenation and haemodynamic conditions, and good neurocognitive function.