Effects of side-to-side neurorrhaphy of phrenic nerve or intercostal nerve on pulmonary function in rats

Objective To verify the safety of a new surgical model by assessing the lung function of phrenic nerve and intercostal nerve via side-to-side with nerve autograft to the neurorrhaphy site of the musculocutaneous nerve in rats. Methods Fifty four SD rats were randomly divided into three groups. Group A was the negative control group, in which the musculocutaneous nerve was transected and directly sutured. The other two groups were the phrenic nerve (group B) and intercostal nerve (group C): after the musculocutaneous nerve was transected and the side-to-side neurorrhaphy was conducted. Sural nerve was used to connect the musculocutaneous nerve neurorrhaphy site and the donor nerve as phrenic nerve or intercostal nerve. Lung function test was conducted at 1, 2 and 3 months postoperatively. Results No significant difference was detected from each parameter including breathing frequency (F), minute ventilation (MV), inspirationand expiration time (Ti and Te), peak inspiratory and expiratory flow (PIF and PEF) and 50% expiratory flow (EF50) of lung function test among group A, B and C at 1, 2 and 3 months postoperatively. Conclusion Side-to-side neurorrhaphy has no obvious damage to pulmonary function. This new method is safe and has great advantages in clinical application. Key words: Rats; Respiratory function tests; Phrenic nerve; Intercostal nerve; Side-to-side neurorrhaphy