Esophageal dysfunction in cervical spinal cord injury: a potentially important mechanism of aspiration

Respiratory complications are a major cause of morbidity and mortality in patients with cervical spinal cord injury (CSCI). We hypothesized that patients with CSCI had esophageal dysfunction, predisposing them to aspiration. The purpose of this study was to characterize esophageal function in these patients.

CSCI and similarly injured control (spinal cord injury below T1) subjects were prospectively enrolled from two trauma centers. All underwent esophageal manometry to measure lower (LES) and upper esophageal sphincter (UES) pressures. A subset of patients had detailed manometry and 24-hour pH studies performed to evaluate dynamic esophageal function.

Eighteen CSCI and five control subjects were enrolled. The groups were similar with regards to age, sex, injury mechanism, Injury Severity Score, and hospital stay. Resting LES and UES pressures were similar in CSCI and control patients and did not differ from established norms. Five CSCI and two control patients underwent detailed manometric assessment. Defective UES relaxation was observed in all CSCI patients but not controls. CSCI patients had increased UES relaxation pressures (18.4 +/- 5.3 versus 3.9 +/- 0.7 mm Hg; p = 0.01) and UES bolus pressures (23.8 +/- 2.2 versus 10.2 +/- 6.9 mm Hg; p = 0.006) compared with controls. Esophageal body and LES function were normal. Two of five CSCI patients had abnormal 24-hour pH studies.

Patients with CSCI demonstrate significantly disturbed dynamic function of the pharynx and UES while resting parameters remain normal. Because adequate UES relaxation is critical to the clearance of secretions and coordination of swallowing, this is an important potential mechanism of aspiration in patients with CSCI.