Inspiratory muscle weakness, diaphragm immobility and diaphragm atrophy after neck dissection.

Background: Inspiratory strength after a neck dissection has not been evaluated, and diaphragm function has not been adequately evaluated.

Objective: Evaluate diaphragm mobility and inspiratory strength after neck dissection.

Methods: Prospective data collection of a consecutive series of adult patients submitted to neck dissection for head and neck cancer treatment, in a tertiary referral cancer center, from January to September 2014, with 30 days of follow-up. A total of 43 were studied (recruited 56; excluded 13).

Main Outcome Measures: Determine diaphragm mobility and inspiratory muscle strength after neck dissection, using diaphragm ultrasound and by measuring maximal inspiratory pressure (MIP) and sniff nasal inspiratory pressure (SNIP).

Results: Thirty patients underwent unilateral neck dissection, and thirteen patients underwent bilateral neck dissection. Diaphragm immobility occurred in 8.9% of diaphragms at risk. For the entire cohort, inspiratory strength decreased immediately after the dissection but returned to preoperative values after 1 month. Except for those with diaphragm immobility, diaphragm mobility remained unchanged after the dissection. One month after the dissection, the diaphragm thickness decreased, indicating diaphragm atrophy.

Conclusions: Immediately after a neck dissection, just a few patients showed diaphragmatic immobility, and there was a transient decrease in inspiratory strength in all individuals. Such findings can increase the risk of postoperative complications in patients with previous lung disease.