ABSTRACT
Objective:Evaluate the influence of different pressure transmission media of urodynamic water filled catheter(WFC) and air charged catheter(ACC) on the pressure measurement results to determine whether they can be used interchangeably.Methods:The results of 2 147 patients who underwent urodynamic examination in our hospital from January 2014 to December 2020 were retrospectively analyzed. A total of 2 538 times of bladder manometry data were obtained, including 1 299 times in WFC group, 856 times in male and 443 times in female, aged 37(24, 50)years, course of disease 1.2(0.4, 5.0) years, 1 130 times in neurogenic bladder(NB)and 169 times in non-neurogenic bladder(N-NB); In ACC group, there were 1 239 times, 773 times for male and 466 times for female, with age of 37(24, 55)years, course of disease of 1.5(0.5, 6.0)years, 1 040 times for Nb and 199 times for N-NB. There was no significant difference in baseline data of general clinical data between the two groups. The intravesical pressure(Pves), intra-abdominal pressure(Pabd)and detrusor pressure(Pdet) of WFC and ACC patients during filling and urination were analyzed. For traumatic spinal cord injury(SCI) and idiopathic patients, the two sets of pressure measurement data were analyzed separately. Nonparametric test and Chi-square test were used to compare the Pves, Pabd, and Pdet recorded by the two manometry catheters before, at the end and after urination, the maximum detrusor pressure at DO(Pdet.max-DO), and the maximum detrusor pressure during spontaneous urination (Pdet. max) and the detrusor pressure (Pdet.Qmax) corresponding to the maximum urine flow rate, the maximum urethral pressure (MUP) and the maximum urethral closure pressure (MUCP) during resting urethral pressure profile, and the initial cough Pdet signal pattern (typeⅠ, typeⅡand typeⅢ).Results:Regardless of the cause, the Pabd values measured by ACC were significantly higher than WFC before filling, end filling and after voiding[18(10, 26)cmH 2O vs.15(11, 21)cmH 2O; 23(16, 31)cmH 2O vs. 20(14, 26)cmH 2O; 23(15, 31)cmH 2O vs.18(12, 24)cmH 2O], and Pdet were significantly lower than WFC[0(0, 0) cmH 2O vs. 0(0, 1)cmH 2O; 5(1, 13)cmH 2O vs. 9(4, 17)cmH 2O; 6(1, 12)cmH 2O vs. 7(3, 14)cmH 2O]. In the initial cough state, Pves and Pabd increase value were also significantly lower than that of WFC [22(12, 36)cmH 2O vs. 23(14, 38)cmH 2O; 20(10, 33)cmH 2O vs. 21(12, 36)cmH 2O]. The Pves measured by ACC was also significantly higher than WFC before filling and after voiding[18(10, 27)cmH 2O vs. 16(11, 21)cmH 2O; 30(22, 39)cmH 2O vs. 26(20, 36)cmH 2O]. Maximum urethral pressure (MUP) and maximum urethral closure pressure (MUCP) measured by ACC were significantly higher than WFC [91(69, 118)cmH 2O vs.81(64, 106)cmH 2O; 77(55, 103)cmH 2O vs. 68(48, 91)cmH 2O], and there were no significant differences in Pdet.max-DO、Pdet.max和Pdet.Qmax. For patients with traumatic SCI, the Pves measured by ACC was significantly higher than WFC before filling[15(10, 24)cmH 2O vs. 14(10, 20)cmH 2O], and only MUP was significantly higher than WFC in the measurement of urethral pressure[95(71, 119)cmH 2O vs. 85(65, 112)cmH 2O], and there were no significant differences in Pdet.max-DO, Pdet.max, Pdet.Qmax and MUCP. For idiopathic patients, Pves measured by ACC before filling and after urination were significantly higher than WFC[25(20, 29)cmH 2O vs. 18(11, 23)cmH 2O; 35(29, 44)cmH 2O vs. 28(20, 38)cmH 2O], while Pdet.max-DO, Pdet.max, Pdet.Q max, MUP and MUCP were not significantly different in different pressure measurement systems. For the comparison of the initial cough Pdet signal pattern, ACC is easier to detect type Ⅰ, and WFC is easier to detect type Ⅱ and type Ⅲ. Conclusions:Compared with WFC, ACC measured higher Pves and Pabd and lower Pdet in resting state, and lower Pves and Pabd in initial cough state. The pressure values and signal pattern measured by WFC and ACC are not completely consistent, so they cannot be used interchangeably.
ABSTRACT
INTRODUCTION AND HYPOTHESIS: To determine whether pressure readings measured with air-filled catheter (AFC) and water-filled catheter (WFC) systems are equivalent during cystometric assessment, especially in case of pressure measurements at Valsalva manoeuvres and coughs. METHODS: Twenty-five subjects were recruited. The commercially available 7-Fr TDOC AFC, which simultaneously reads water and air pressures in the bladder and rectum, was used to compare filling and voiding data recordings. Data were compared using paired t-tests, Bland-Altman plots and linear correlation methods, respectively. RESULTS: Pressure readings measured by the two systems showed a good correlation at Valsalva manoeuvres [R2 = 0.988, 0.968 for vesical pressure (Pves) and abdominal pressure (Pabd), respectively] and at coughs (R2 = 0.972, 0.943 for Pves and Pabd, respectively). There was a statistically significant difference between the two different measurement modalities at coughs (p < 0.01), initial resting pressure (p < 0.01) and the maximum pressure at detrusor overactivity (p < 0.01). This indicated that the difference between the two measurement modalities during Valsalva manoeuvres could reach up to 5.2 cmH2O and 8.1 cmH2O in Pves and Pabd measurements, respectively. During coughs, the difference could reach up to 20 cmH2O and 19.5 cmH2O in Pves and Pabd measurements, respectively. CONCLUSIONS: Pressure recordings from AFC and WFC systems appear to be interchangeable for some urodynamics parameters such as Pves at Valsalva manoeuvres if the baseline pressure is compensated, but not for fast-changing pressure signals such as coughs. This has to be considered when pressures are being taken with the AFC.