Feline ureteral obstructions Part 2: surgical management

Abstract

Feline obstructive ureteral disease will likely remain a common and frustrating cause of critical illness in cats for the foreseeable future. Since many cats are uraemic and cardiovascularly unstable secondary to obstructive nephropathy, prompt recognition using clinical intuition, blood work and diagnostic imaging is essential to make a timely diagnosis and decision about timing for intervention, if indicated. Multiple surgical and interventional procedures exist for the management of feline ureteral obstructions but there is no ideal technique and all currently available procedures carry risk of infection, re-obstruction, urine leakage and the need for additional procedures in the future. Therefore, until clear, evidencebased guideline exist, the decision about which ureteral procedure to perform in cats should be guided by nature of the obstruction, location, concurrent urolithiasis, infection and surgeon preference. In all likelihood, ureteral surgery, stents and ureteral bypass devices will continue to remain viable options and the decision about which procedure to use will be made on a case-by-case basis.

Influence of suture diameter on microsurgical ureterorrhaphy in rabbits: an experimental study

“…The thickness of the 6 − 0, 8 − 0 and 10 − 0 sutures represents, respectively, 20 mµ, 40 mµ and 70 to 99 mµ [21], and although the three diameters are considered thin for general surgical procedures, it is noted that, for millimeter structures such as the ureter, this difference is an important characteristic regarding to the non-compromise of the lumen. Using thicker sutures, coupled with traumatic needles and with the inappropriate aid of magni cation, makes ureterorrhaphy a challenging procedure [11], corroborating the high rates of complications described so far [4,6,7,11].…”

“…Commonly 6 − 0 to 8 − 0 gauge are used for ureteral suture in felines [1][2][3][4][5][6][7][8][9][10][11], whose outside diameter is equivalent to that of New Zealand rabbits, corresponding to 1 mm [20]. The thickness of the 6 − 0, 8 − 0 and 10 − 0 sutures represents, respectively, 20 mµ, 40 mµ and 70 to 99 mµ [21], and although the three diameters are considered thin for general surgical procedures, it is noted that, for millimeter structures such as the ureter, this difference is an important characteristic regarding to the non-compromise of the lumen.…”

“…The width obtained more discreet increases, showing no difference with the control. Considering that acute changes result in larger kidneys, it is possible to correlate the increase in these measures with in ammation and ureteral edema resulting from the surgical procedure [11], causing luminal narrowing and urine accumulation in the kidney in different proportions. These results are reinforced by comparing the data obtained in the second ultrasound assessment, where the difference signi cant length and width were no longer with the control group but with the N6, due to the loss of experimental plots.…”

“…Ureteral surgeries in companion animals can be indicated for the treatment of trauma, congenital anomalies or obstructive uropathies due to intra or extramural injuries [1]. Ureterotomy is one of the most used and traditional surgical techniques, especially for removing ureteral calculi in different species [1][2][3][4][5][6][7][8][9][10][11].…”

“…Despite the increasing use of microsurgery in several elds of veterinary medicine [14], descriptions of microsurgical ureterotomies [1,3,4,[6][7][8][9][10][11] have been associated with several postoperative complications, such as uroabdomen, edema at the suture site and post-surgical stenosis, resulting in high mortality rates [4,19]. It is worth noting that these studies use 5.0 to 8.0 suture gauge, do not standardize the magni cation of the microscope and do not specify the needle used, therefore, it is likely that complications are associated with sutures that cause extensive tissue damage and compromise the lumen, predisposing to chronic in ammation, brosis and stenosis [12].…”