Difficult weaning from mechanical ventilation in the pediatric ICU

Abstract

Background Respiratory disorders are the main cause of respiratory failure in children. Insufficient alveolar ventilation results in hypoxemia and hypercapnia, which contribute to further depression of ventilation, resulting in respiratory failure. Although most patients wean from mechanical ventilation with little difficulty, some patients are unable to maintain sustained efforts of breathing for long periods and develop signs of fatigue. A failed weaning is defined as either the failure of spontaneous breathing trial or the need for reintubation within 48 h after extubation. Objective This study was undertaken to identify the causes of difficult weaning from mechanical ventilation and predict the variables responsible for this difficulty. Participants and methods A prospective study was performed on 100 children, comprising 59 boys and 41 girls. Their ages ranged between 2 months and 10 years. All the children were subjected to a detailed medical history taking, clinical examination, and laboratory investigations (complete blood count, serum electrolytes, and arterial blood gas). Patients were selected to participate in this study on the basis of the inclusion and exclusion criteria. Statistical analysis The Mann-Whitney U -test and the χ 2 -test were used for statistical analysis. Results Among the 100 studied patients, 86 (86%) succeeded in being weaned from mechanical ventilation, whereas the remaining 14 patients (14%) failed to wean. This group included nine children who experienced difficulty in weaning and five children with prolonged weaning. Patients who were successfully weaned spent statistically less time on mechanical ventilation, had lower PaCO 2 , and lower bicarbonate level compared with patients who failed to wean ( P = 0.002, 0.001, 0.04, respectively). There was no association between clinical diagnosis, hematological parameters, serum electrolytes, and weaning success. Conclusion We conclude that patients who were successfully weaned were statistically older, spent less time on mechanical ventilation, had lower PaCO 2 and FiO 2 , and lower bicarbonate level compared with those who failed to be weaned. We did not find a significant relation between the clinical diagnosis, hematological parameters, serum electrolytes, and weaning success.