Citations

Abstract Aim Female urethral stricture disease is rare and has several surgical approaches including endoscopic dilations (ENDO), urethroplasty with local vaginal tissue flap (ULT) or urethroplasty with free graft (UFG). This study aims to describe the contemporary management of female urethral stricture disease and to evaluate the outcomes of these three surgical approaches. Methods This is a multi‐institutional, retrospective cohort study evaluating operative treatment for female urethral stricture. Surgeries were grouped into three categories: ENDO, ULT, and UFG. Time from surgery to stricture recurrence by surgery type was analyzed using a Kaplan–Meier time to event analysis. To adjust for confounders, a Cox proportional hazard model was fit for time to stricture recurrence. Results Two‐hundred and ten patients met the inclusion criteria across 23 sites. Overall, 64% ( n = 115/180) of women remained recurrence free at median follow‐up of 14.6 months (IQR, 3–37). In unadjusted analysis, recurrence‐free rates differed between surgery categories with 68% ENDO, 77% UFG and 83% ULT patients being recurrence free at 12 months. In the Cox model, recurrence rates also differed between surgery categories; women undergoing ULT and UFG having had 66% and 49% less risk of recurrence, respectively, compared to those undergoing ENDO. When comparing ULT to UFG directly, there was no significant difference of recurrence. Conclusion This retrospective multi‐institutional study of female urethral stricture demonstrates that patients undergoing endoscopic management have a higher risk of recurrence compared to those undergoing either urethroplasty with local flap or free graft.

Mechanical ventilation may cause harm by straining lungs at a time they are particularly prone to injury from deforming stress. The objective of this study was to define the relative contributions of alveolar overdistension and cyclic recruitment and “collapse” of unstable lung units to membrane wounding of alveolar epithelial cells. We measured the interactive effects of tidal volume (V T ), transpulmonary pressure (P TP ), and of airspace liquid on the number of alveolar epithelial cells with plasma membrane wounds in ex vivo mechanically ventilated rat lungs. Plasma membrane integrity was assessed by propidium iodide (PI) exclusion in confocal images of subpleural alveoli. Cyclic inflations of normal lungs from zero end-expiratory pressure to 40 cmH 2 O produced V T values of 56.9 ± 3.1 ml/kg and were associated with 0.12 ± 0.12 PI-positive cells/alveolus. A preceding tracheal instillation of normal saline (3 ml) reduced V T to 49.1 ± 6 ml/kg but was associated with a significantly greater number of wounded alveolar epithelial cells (0.52 ± 0.16 cells/alveolus; P < 0.01). Mechanical ventilation of completely saline-filled lungs with saline (V T = 52 ml/kg) to pressures between 10 and 15 cmH 2 O was associated with the least number of wounded epithelial cells (0.02 ± 0.02 cells/alveolus; P < 0.01). In mechanically ventilated, partially saline-filled lungs, the number of wounded cells increased substantially with V T , but, once V T was accounted for, wounding was independent of maximal P TP . We found that interfacial stress associated with the generation and destruction of liquid bridges in airspaces is the primary biophysical cell injury mechanism in mechanically ventilated lungs.