Blood pressure response to detrusor pressure elevation in patients with a reflex urinary bladder after a cervical or high thoracic spinal cord injury

Abstract

In 12 patients with a reflex urinary bladder after a cervical or high thoracic spinal cord injury, blood pressure was measured every 30 s during cystometry. Four consecutive cystometries were performed by means of suprapubical catheters and 50 ml/min filling rate. The aim was to improve the methodological basis for cystometrical studies of paroxysmal hypertension and its treatment. In each cystometry there was an elevation of the systolic (20-60 mmHg) and the diastolic (15-55 mmHg) blood pressure. The maximum blood pressure always occurred during the emptying phase and always in close relation to the peak of the detrusor pressure. The amplitude of the blood pressure response varied intraindividually, but did not change in any particular direction during the series of cystometries. Thus, a cystometrical method which stimulates the detrusor in a physiological way is sufficient to give the typical uninhibited blood pressure reaction in most patients with a reflex bladder and a spinal reflex vasomotor function after a high level spinal cord injury. The blood pressure reaction obtained with this method is probably representative for the daily reaction during physiological reflex emptying of the bladder. To describe the maximum blood pressure reaction, it has to be measured during a well defined emptying phase and close to the occurrence of the maximum detrusor pressure. Since repetition of cystometry did not change the blood pressure response, this cystometrical method is useful for evaluation of pharmacological intervention.