Statistical analysis
SPSS software was used for statistical analysis, the viscosity of sputum, humidification effect, and degree of secondary lung infection were tested by rank and sum. The patients’ disease distributions, phlegm scab formation, airway spasm, were analyzed using Chi square test. The patient’s basic situation, daily sputum intake times, respiration related physiological indicators, daily nursing times and internal satisfaction score were analyzed with variance analysis, P 0.05 was considered statistical significant.