Non-Invasive Measurement of Intra-Abdominal Pressure through Abdominal Wall during Urodynamic Study

Abstract

We found that the intra-abdominal pressure could be measured non-invasively, simply and directly through the abdominal wall using a pressure transducer that we used for routine urodynamic studies. We designed a simple device, “transducer attacher”, for attaching the transducer to the abdominal wall. To evaluate the utility of pressure this measured, we compared it with the empty intravesical pressure which is equal to the intraabdominal pressure. Pressure through the abdominal wall did not differ significantly from that of the empty urinary bladder measured on 33 strainings performed by 15 patients complaining of urinary disturbance. The relationship between the rise in empty intravesical pressure (X) and the abdominal wall pressure (Y) was shown by the equation Y = 1.13X-2.89 (r = 0.971, p<0.01). These findings indicate that the pressure measured through the abdominal wall represents the intra-abdominal pressure. This new technique presents an alternative to monitoring the rectal pressure in urodynamic studies.