Most common causes of difficult urethral catheterization. *Pooled cases from Beaghler’s et al , Freid’s et al  and Mistry’s et al  series. Included are the 54 patient from Beaghler’s series all of which underwent flexible cystoscopy, and the 13 patient in Mistry’s series that underwent flexible cystoscopy. Twenty patient from Freid’s series were included too, but it was not mentioned in the article how the cause of difficult urethral catheterization was found in these patient
Blind Passage of Glidewire
After failed attempts at catheterization by the urologist or experienced technician, we recommend trying to pass a glidewire blindly next. It is imperative to avoid any stiff glidewires because of the potential for bladder or urethral perforation. Several authors have demonstrated the safety and efficacy of glidewires [1, 3–5, 9].
In our consecutive series of DUC, after failed attempts at catheterization, 75 % (24/32) of patients were successfully catheterized after the blind placement of a glidewire. We used both straight and angled tip glidewires. Sometimes when either the straight or angled tip did not go through we tried the other type.
Glidewires are usually 150 cm in length. The glidewire should be advanced gently into the bladder and coiled inside the bladder until <40 cm of glidewire stick out of the urethra. This assures proper placement in the bladder since advancing this much glidewire into a false passage or urethral perforation would encounter much more resistance and be almost impossible to do with a regular glidewire (but possible with a stiff glidewire). As one advances the wire, effort is made to “feel” the obstructive area to try to maneuver the glidewire past it. This may be facilitated by grasping the glidewire with a hemostat or moist gauze.
Once the bladder is secured, a 16 Fr council tip catheter is attempted (successful in 8/24), or a 12 Fr silicone catheter using the Blitz technique (Fig. 12.2) (successful in 13/24). If neither catheter will go in, dilating with a ureteral access sheath is safer due to the tapered tip and the hydrophilic nature. This is enough to be able to subsequently pass the 12 F silicone catheter. In our series, only 3 patients had to be dilated with a 12 F ureteral access sheath.
The Blitz technique
If unable to pass the glidewire blindly, cystoscopy may be of help . Eight patients in our series underwent flexible cystoscopy. The etiology in these cases is usually false passage or a pinpoint stricture.
False passages are usually ventral and so the true lumen is found dorsally. The trick when advancing the cystoscope is to point the tip towards the ceiling directly facing the urethral mucosa and following the mucosa into the bladder. No attempt to find the center of the urethral lumen is made as when doing routine cystoscopies.