RESUMEN
Objective:We compare the consistency, similarities and differences of operating procedures, data and conclusions of air-charged catheters(ACC) and water-filled catheters(WFC), as simultaneously using ACC and WFC in pressure-flow study(PFS).Methods:This study was a prospective, synchronously controlled study, including eligible patients who underwent PFS in the Department of Urology, Beijing Chaoyang Hospital from January 2021 to March 2021. Inclusion criteria: ① Patients need PFS for lower urinary tract symptoms like frequency of urination, urgent urination, urinary incontinence and dysuria; ② Age over 18 years old. Exclusion criteria: ① Unable to complete or cooperate during the urodynamic test; ② Patients with severe urethral stricture or acute stage urinary tract infection; ③ Pregnant women. The bladder pressure was measured continuously by using a 7FDR T-DOC ?AC three-chamber bladder pressure tube, which linked to ACC sensor and improved WFC pressure conduction module. At the same time, 7FA T-DOC ?AC single-lumen rectal pressure tube and 7F Labori-CAT411 double-lumen water sac abdominal pressure tube was used to measure the ACC and WFC rectum pressure, respectively. We recorded the Pdet, Pves and Pabd measured by ACC and WFC, at the point of initial sitting position, bladder filling at 100 ml, 150 ml, 200 ml, cough, Q max, maximum Pdet and the end of urination, and compared the mean values, differences, and consistencies of our data. Result:A total of 63 patients (26 female, 37 male) were included in this study, with an average age of 59.19 years (25-86 years old). During bladder filling phase, the mean values of Pves measured by ACC and WFC were 30.78/24.67cmH 2O (initial sitting position), 29.79/25.13cmH 2O (100 ml), 30.87/25.90cmH 2O (150 ml) and 30.95/26.17cmH 2O(200 ml), respectively, the mean value of Pabd were 30.03/24.17cmH 2O (initial sitting position), 28.81/21.78cmH 2O (100ml), 28.89/21.38cmH 2O (150ml), 28.44/21.60cmH 2O (200ml), respectively, and were significantly different at each sampling point ( P<0.01). During urination period, no significant differences were found in data( P>0.05), and the data measured with ACC and WFC system have good consistency. There were significant differences in Pves(mean 57.30/49.95 cmH 2O, respectively) and Pdet(mean 54.21/43.10 cmH 2O, respectively) between ACC and WFC in cough ( P<0.01), but there was a strong linear correlation between these data between two systems(R 2=0.792 in Pves and 0.756 in Pabd). Bland-Altman analysis showed that detrusor pressure at the maximum urine flow rate maintained good consistency between ACC and WFC, which 95% CI was -13.9 cmH 2O to 15.8 cmH 2O. Conclusions:In PFS, although the ACC measurement values (Pves and Pabd) during the filling phase are higher than those WFC readings, but the absolute measurement difference is small, so there is no practical meaning in clinical practice. There was no significant difference in detrusor pressure measured during voiding phase, which indicated that the urodynamic judgment and clinical conclusions of the two systems are highly consistent in judgment of the detrusor contractility and the bladder outlet obstruction.
RESUMEN
Urodynamics is able to reproduce the patient's lower urinary tract symptoms and to explain patient's bladder problems objectively. Currently, the most commonly used urodynamic manometry catheter is water filled catherters, which is widely recognized due to its economic and healthy advantages. However, air bubbles and patient's activities can affect the quality and speed of signal transduction, interfering the explanation of the pressure results. The air-filled catheters are easy to operate, and the measures are unaffected by air bubbles and patient's activities, which have gradually begun to be used in urodynamic study in some areas. However, there are several differences between them in terms of fluid mechanics principle, zero set and detailed operations which directly and indirectly lead to the different pressure results. The researches on air-filled catheters at home and abroad are still not perfect. This article gave a detailed comparison between them based on the present studies from the following aspects: the essential structure, the developing history, the fluid mechanics principle, the zero pressure point setting, the frequency response, the cystometrogram, the urethral pressure profile, the conversion algorithm, and the urinary tract infection after the investigation, etc.