Pulmonary functions and responses to exercise of patients following cranio cerebral injury

To assess the causes of excessive fatigue among patients who have recovered from cranio-cerebral injury (CCI) nineteen patients and fourteen healthy controls underwent pulmonary function testing at rest and cardiopulmonary evaluation during two submaximal exercise work-loads. Total lung capacity, vital capacity and forced expired volume were reduced by 25--40% among the patients. Functional residual capacity was normal. No improvement was elicited by inhalation of Ventolin and bronchoconstriction could thus be excluded. The above pattern may result from either decreased compliance of the chest wall or from weak (or non-coordinated) respiratory musculature. Exercise heart rate, minute ventilation and ventilatory equivalent were higher, and O2 pulse lower, among the CCI patients compared with the controls. This indicates lower circulatory and ventilatory efficiency during exercise among the patients, possibly due to habitual hypoactivity and detraining.