Restrictive ventilatory dysfunction in stroke: its relation to locomotor function.

Static and dynamic lung volumes, maximum respiratory pressures and lung compliance and resistance were registered in 54 subjects with hemiplegia or hemiparesis after stroke. These measures of ventilatory function were related to the degree of motor impairment and to the interval between stroke and investigation. In general ventilatory function, particularly parameters depending upon expiratory force, was restricted. This was most pronounced in subjects with severe hemiplegia while those with hemiparesis had only small changes. Since dynamic lung volumes (corrected for volume loss), lung compliance and resistance were all normal, it is evident that intrinsic lung function was unaffected. Inspiratory capacity - but no other measured variables of respiratory function - was lower six months after the stroke than earlier. It is suggested that expiratory muscle dys-coordination and weakness caused expiratory dysfunction while the less pronounced inspiratory restriction may be caused by muscular dysfunction and, as time goes by, by rib cage contracture.