Abstract:

Objective To evaluate the tolerability, safety and efficacy of high-frequency chest wall oscillation (HFCWO) in elderly patients after cardiac surgery. Methods Two hundred and one consecutive patients aged more than 70 undergoing cardiac surgery received HFCWO combined with manual chest physiotherapy 6 to 8 h after extubation (HFCWO group). The tolerability of patients to HFCWO therapy was assessed with Likert scale, and the changes of circulatory and respiratory parameters of heart rate, systolic blood pressure, central venous pressure, mean pulmonary arterial pressure, breathing rate and pulse oxygen saturation were measured 10 min before, during and 10 min after initial HFCWO therapy. Besides, another 165 consecutive patients aged more than 70 undergoing cardiac surgery treated only with manual chest physiotherapy were served as controls, and the related clinical parameters of incidences of postoperative pneumonia, pleural effusion, atelectasis, re-endotracheal intubation, durations of ICU stay and antibiotics use and length of stay were compared between two groups. Results A total of 984 therapies of HFCWO were performed, of which 813 (82.62%) were well tolerated, while 66 (6.71%) were hardly tolerated. No HFCWO therapy-related adverse events were reported. There was no significant change in heart rate, systolic blood pressure, central venous pressure, mean pulmonary arterial pressure, breathing rate and pulse oxygen saturation 10 min before, during and 10 min after initial HFCWO therapy (P>0.05). The incidences of postoperative pneumonia and pleural effusion in HFCWO group were significantly lower than those in control group (3.98% vs 9.09%, P<0.05; 6.47% vs 12.72%, P<0.05), and the duration of postoperative antibiotics use and length of stay in HFCWO group were significantly shorter than those in control group [(5.07±2.23) d vs (6.98±2.41) d, P<0.05; (9.58±4.10) d vs (11.79±5.06) d, P<0.05], while there was no significant difference in the incidences of postoperative atelectasis and re-endotracheal intubation and duration of postoperative ICU stay between two groups (P>0.05). Conclusion HFCWO is a safe and well-tolerated adjunct after extubation following cardiac surgery in elderly patients. Combined with manual chest physiotherapy, HFCWO may help to reduce postoperative pneumonia, pleural effusion and use of antibiotics.

Key words: high-frequency chest wall oscillation, cardiac surgery, elderly, chest physiotherapy