Urinary drainage and penile obstructions are the two most common urological problems needing improvised treatment.
Anesthetic jellies (gels), such as lidocaine 2%, reduce the discomfort of male catheterization, although this is not true in women.1,2 Lidocaine jelly may not be available, so it helps to know about the alternatives.
Diphenhydramine (e.g., Benadryl) and promethazine (e.g., Phenergan) may be used effectively as urethral anesthetics. The dose is the same, or less, than would be used orally. Inject the drug into the urethra using a bulb syringe and keep it in place for about 5 minutes using a penile clamp or equivalent. Some patients experience an initial burning sensation. The anesthesia lasts about 1 hour. To obtain more extensive anesthesia, coat a small urethral sound with an ointment of these medications and leave in it place about 5 minutes before passing larger sounds.3
Use mineral oil to lubricate urethral catheters if standard lubricating jellies are unavailable.4 In women, apply 10% cocaine jelly with a cotton-tipped applicator for an effective urethral anesthetic. Leave this in place for 5 minutes.5
Difficult Urethral Catheter Placement
Passing a urethral catheter is almost routine from the clinician's perspective. Some catheters are difficult to pass, especially in older men. When calling the urologist is not an option, the following technique may make catheter insertions more successful.
In males >50 years old, use a syringe to inject 25 to 50 mL lidocaine jelly 2% into the urethra before attempting to pass any catheter. If lidocaine jelly is not available, use any sterile gel (e.g., K-Y). If you anticipate that passing a urethral catheter will be difficult, use at least an 18- to 20-Fr Foley rather than a smaller-sized catheter. Smaller catheters simply bend if they hit an obstruction, rather than passing into the bladder. Use slow, steady pressure to insert it all the way to the Foley's hub. Do not inflate the balloon until the catheter is fully inserted and urine returns. Inflate balloons with water only; do not use normal (0.9%) saline. (See "Retained Urethral Catheters" later in this chapter.)
Use a coudé catheter if you suspect that the patient may have an enlarged prostate. A coudé catheter has a gentle upward curve at its distal 3 cm that allows easier passage through an enlarged prostate. When inserting a coudé catheter, point the tip anteriorly. This means that the balloon inflation side port should be facing up (on the same side as the curve). If the patient has a red catheter in place, it generally means that it is either a coudé or a Councill (used by urologists to pass over a guidewire). In either case, beware of removing it for replacement.
If multiple attempts at catheter placement have failed, a suprapubic aspiration using a needle ...