Context: Respiratory failure, atelectasis, pneumothorax, pleural effusion and sputum retention are all possible pulmonary complications, especially in children in post-operative phase. The objectives of blow bottle PEP are to maximise gas exchange, lessen blockage and enhance ventilation.   Aim: To analyse how blow bottle-positive expiratory pressure affects the pulmonary functions of the children who underwent a median sternotomy.   Methods and Material: A pilot study was carried out on six children, where both groups underwent deep breathing exercises. Additionally, the experimental group received blow bottle expiratory therapy over a period of post-operative 5 days (from 3rd to 7th POD). The deep breathing exercises were performed in four sessions daily, while the blow bottle positive pressure expiratory therapy was given for 4 sessions, each session consists of 3 sets of 10 repetitions, with rest intervals of 5-10 minutes between sets. Following the pilot study, a main study was conducted on 28 additional children, who were randomly assigned to either the experimental or control groups. The same procedures were applied, and no complications were observed during the therapy sessions. Statistical analysis used: PEFR (p<0.001), CE (p<0.001)and spo2 (p<0.004) all showed substantial improvement within the group as well as between-group analysis.

Conclusions: To improve the pulmonary function of the children who had median sternotomy, deep breathing exercise combined with blow bottle-positive expiratory pressure was more effective than deep breathing exercise alone.