Catheterizable serous lined urinary outlet in children and adolescents: a choice when other treatments fail

PURPOSE

We evaluated the functional outcome of continent catheterizable outlet using the serous lined extramural tunnel technique as a continence mechanism in children and adolescents.

MATERIALS AND METHODS

We retrospectively studied all patients who underwent continent catheterizable stoma using the serous lined extramural technique between May 1993 and March 2008. Patient records were reviewed for age, sex, indication for surgery, surgical details and postoperative course. All patients were evaluated for continence with emphasis on frequency of clean intermittent catheterization. Urodynamic evaluation was done for patients with leaking stoma. Stoma related complications were also recorded.

RESULTS

A total of 37 boys and 23 girls 3 to 18 years old underwent continent catheterizable stoma using the serous lined extramural technique. Total bladder substitution was performed in 13 patients using continent ileal W-shaped reservoir, and 47 patients underwent augmentation ileocystoplasty mounted with serous lined outlet. The outlet channel was appendix in 39 patients (65%), tapered ileal segment in 13 (21.5%) and Monti ileal tube in 8 (13.5%). After a median followup of 43 months (range 10 to 180) 55 patients (91.6%) achieved continence, with catheterization frequency of 3 to 5 times during the daytime and 1 to 2 times at night. Stoma related complications were leaking stoma in 5 patients (8.4%), stomal stenosis in 6 (10%), parastomal hernia in 2 (3.3%) and reservoir stones in 8 (13.3%). Reoperation rate was 18.3% (11 patients).

CONCLUSIONS

The serous lined continent outlet seems to be a durable and efficient technique for treating children with incontinence, with an acceptable complication rate.

Complications of radical cysto-urethrectomy using modified Clavien grading system: prepubic versus perineal urethrectomy

OBJECTIVES

• To assess the impact of both prepubic and perineal urethrectomy on the complication rate and grade when cysto-urethrectomy is planned. • To review the perioperative complications of radical cysto-urethrectomy and grade them according to the modified Clavien classification system.

PATIENTS AND METHODS

• A total of 186 radical cysto-urethrectomies were performed between 1984 and 2008 • Patients' charts were retrospectively reviewed, focusing on operation duration, hospital stay and complications arising. • According to this new classification, perioperative complications were stratified into five grades.

RESULTS

• Prepubic urethrectomy was done in 71 patients (group I) while perineal urethrectomy was done in 115 patients (group II). • The mean operation duration was significantly lower in group I than in group II (173.8 and 208.9 min in groups I and II, respectively; P= 0.003). • There were a total of 46 perioperative complications in 186 (24.7%) patients, 21 (29.5%) in the prepubic group and 25 (21.1%) in the perineal group. • There were 19 (90.5%) and 18 (72%) low-grade (G1-3) complications in the prepubic and perineal groups, respectively, and two (9.5%) and seven (28%) high-grade (G4-5) complications in the prepubic and perineal groups, respectively (P= 0.033). • The mean hospital stay was significantly lower in group I than in group II (14.5 and 17.6 days in groups I and II, respectively; P= 0.047).

CONCLUSION

• The prepubic approach has a lower incidence of serious complications with shorter operation duration and shorter hospital stay.

Setaria equina: in vivo effect of diethylcarbamazine citrate on microfilariae in albino rats

Although diethylcarbamazine citrate (DEC) is successful drug in eliminating human filariasis, yet, its mode of action is still debatable. Herein, the effect of DEC to treat albino rats infected with the animal filarial parasite Setaria equina was tested. Microfilarial (mf) counts and sections from liver, lung, kidney as well as spleen were investigated at different time points after treatment by light microscopy. After 45 and 300min of treatment, a significant decrease in blood mf was observed accompanied by adherence of degenerated mf to both kupffer cells and leukocyte in liver sections. In lung sections, loss of sheath was observed at 45min, while degeneration was observed at later time points. In kidney sections, more mf counts and less matrix were observed in the glomeruli at all time points after treatment. Degenerated mf were observed in spleen sections only at, late time point, 480min after treatment. In conclusion, one of the possible mechanisms by which DEC reduces blood microfilarial count is trapping larvae in organs and killing them through cellular adherence.

The value of frozen-section analysis of ureteric margins on surgical decision-making in patients undergoing radical cystectomy for bladder cancer

OBJECTIVE

To prospectively investigate the value of routine frozen-section analysis (FSA) of the ureteric margin for detecting distal ureteric malignancy in patients undergoing cystectomy for bladder transitional cell carcinoma (TCC).

PATIENTS AND METHODS

In all, 100 consecutive patients had a radical cystectomy for TCC of the bladder; routine FS biopsies were obtained from the lower ureters of all. Definitive pathology with step-sectioning of the lower ureters was reviewed, and the results of paraffin-wax embedded sections and FSA were compared. The true incidence of distal ureteric malignancy was identified and correlated with different clinical and pathological variables.

RESULTS

There were 193 ureteric specimens examined; 16 ureters (8.3%) in 14 patients showed evidence of malignancy by FSA. True distal ureteric malignancy was diagnosed in 29 ureteric specimens (15%) in 24 patients. The sensitivity and specificity of the FSA were 45% and 98%, respectively, while the positive and negative predictive values were 81% and 91%, respectively. There was no significant correlation between distal ureteric malignancy and: patient age, tumour site or morphology, clinical or pathological staging, ipsilateral hydronephrosis, suspicious intraoperative ureter, biopsy or tumour grade, associated carcinoma in situ or nodal involvement. Male gender and positive intraoperative FSA were the only predictors significantly associated with distal ureteric malignancy by univariate analysis (P = 0.01 and <0.01, respectively). Both predictors remained significant on multivariate analysis.

CONCLUSION

A positive ureteric FSA during cystectomy has a high predictive value in the diagnosis of distal ureteric malignancy, and is justified as an independent predictor in male patients with bladder TCC.

Impact of Pre-operative MRI-measured Membranous Urethral Length on Urinary Continence after Radical Cystectomy and Orthotopic Substitution: Clinical and Urodynamic Evaluation

PURPOSE

We aimed to determine the impact of membranous urethral length as measured by preoperative magnetic resonance imaging (MRI) upon continence following radical cystectomy and orthotopic substitution.

MATERIALS AND METHODS

A total of 40 male patients (mean age 55.7 +/- 7 years) were subjected to radical cystectomy and orthotopic ileal substitution for bladder cancer. Membranous urethral length was measured by preoperative MRI utilizing coronal oblique high resolution T2 weighted images. In all evaluable patients, day and night continence statuses as well as time to stable continence were recorded. Urodynamic assessment included medium fill pouchometry and urethral pressure profilometry.

RESULTS

Of all patients 10 were non-evaluable. Mean follow-up period was 8.1 +/- 1.9 months. All the evaluable patients were continent by daytime. On the other hand, 13 were continent by night (43.3%), 13 showed occasional enuresis (43.3%) and 4 were nightly enuretic (13.4%). Mean membranous urethral lengths were 14 +/- 1.9, 13.8 +/- 1.9 and 12.8 +/- 1.7 mm in the three groups, respectively (P = 0.51). Mean time to reach stable postoperative daytime continence was 5.4 +/- 4.6 whilst it was 12.5 +/- 7.4 weeks for nighttime continence. There was no significant correlation between preoperative membranous urethral length and time to stable day or night continence (R = -0.11, -0.08, respectively). Moreover, such correlation was not observed with postoperative urethral pressure profilometry parameters including maximum urethral pressure, maximum urethral closure pressure or functional urethral length (R = -0.33, -0.38, -0.16, respectively).

CONCLUSION

Preoperative MRI-measured membranous urethral length has no value for judgment of postoperative continence status following radical cystectomy and ileal bladder substitution.

Percutaneous treatment of large upper tract stones after urinary diversion

OBJECTIVES

To present our experience in percutaneous management of large upper tract stones after urinary diversion.

METHODS

From October 1984 to March 2005, 20 percutaneous nephrolithotomy and 4 antegrade ureteroscopy procedures were performed in 17 men and 7 women, with a mean age of 53.5 years. The urinary diversions were an ileal W neobladder, hemi-Kock pouch, ileal conduit, and rectal bladder in 10, 7, 4, and 3 patients, respectively. The median interval between diversion and stone management was 1.5 years. Success was defined as a stone-free, nonobstructed renal unit at 3 months after the intervention. Follow-up was performed every 6 months with intravenous urography or noncontrast computed tomography for diagnosis of stone recurrence and evaluation of renal morphology.

RESULTS

Renal punctures were guided with ultrasonography in 18 patients (75%) and fluoroscopy in 6 patients. One intraoperative complication (4.16%) and two postoperative complications (8.3%) occurred. All patients with ureteral stones became stone free after one procedure. Auxiliary procedures were needed in 5 patients after percutaneous nephrolithotomy; 2 patients required a second session and 3 needed extracorporeal shock wave lithotripsy. The overall success rate was 87.5% (21 patients). One patient with treatment failure underwent open surgery, and two with small residual fragments were followed up. Long-term follow-up data were available for 15 patients. The stone recurrence rate was 33.3% (5 patients) after a median follow-up of 40 months (range 14 to 132). Recurrent stones were treated with extracorporeal shock wave lithotripsy.

CONCLUSIONS

The results of our study have demonstrated that percutaneous treatment of large upper tract stones after urinary diversion offers a high success rate with minimal morbidity. However, regular follow-up after treatment is recommended.

A randomized study comparing an antireflux system with a direct ureteric anastomosis in patients with orthotopic ileal neobladders

OBJECTIVE

To assess the benefit of an antireflux system in patients with orthotopic ileal neobladders, as there is controversy about whether reflux prevention offers any advantages.

PATIENTS AND METHODS

We conducted a randomized prospective study between January 2002 and March 2004, on 60 patients (53 men and seven women) with a mean (sd) age of 52.7 (7.3) years, who were candidates for orthotopic neobladders. Patients with comorbidities were excluded. Preoperative evaluation included intravenous urography (IVU), cystoscopic biopsy and radioisotope renography to evaluate the differential glomerular filtration rates (GFRs). Cases with normal kidneys and ureters, and with similar GFRs, were enrolled. Surgery comprised a standard radical cystectomy with pelvic lymphadenectomy. The ureters were randomized to either a direct anastomosis into a 5-cm ileal chimney on one side, or to be implanted using the antireflux serous-lined extramural tunnel on the contralateral side in the same patient. Regular follow-up included IVU and renography every 6 months in cancer-free patients.

RESULTS

The mean (sd) follow-up was 23 (9.6) months. There was prolonged urinary leak from a refluxing ureter in one patient that was treated with a temporary percutaneous nephrostomy. Symptomatic pelvic collections required tube drainage in six cases. Six ureters developed early anastomotic strictures (one direct and five antirefluxing), and were treated with endoscopic ureterotomy in three and open revision in three. Serum creatinine levels were normal in all patients throughout the observation period. GFRs were similar in the two groups. The mean GFRs before surgery and at 6, 12, 18, and 24 months after cystectomy were: 55.1, 50.7, 49.4, 52.2 and 53.9 mL/min for the direct side; and 56.1, 53, 52.4, 53.2 and 50.4 mL/min for renal units with antirefluxing implantation. There was a significant deterioration of the GFRs due to anastomotic strictures, from 48.6 (6.7) mL/min before surgery to 31.8 (15.9) mL/min after the revision (P = 0.01).

CONCLUSIONS

The antireflux procedures were associated with a higher incidence of anastomotic strictures than the direct methods and there was a significant deterioration of renal function after obstruction. The long-term follow-up data are awaited.

Asymptomatic bacteriuria in men with orthotopic ileal neobladders: possible relationship to nocturnal enuresis

OBJECTIVE

To assess prospectively the incidence with time of asymptomatic bacteriuria in patients with orthotopic ileal neobladders, and the possible effect on neobladder function.

PATIENTS AND METHODS

In all, 47 patients (mean age 52.7 years, sd 8.7, range 31-68) with uncomplicated orthotopic ileal neobladders were prospectively evaluated. With no antibiotic manipulation, consecutive urine cultures were assessed monthly. Continence was assessed by direct information from the patients at each follow-up visit.

RESULTS

Overall, 797 samples were cultured from the 47 patients (mean 17.6, sd 7.1). There was a steady decrease in the incidence of positive cultures, from 74.5%, to 35.6% and 6.7% at 1, 6 and 18 months, respectively. While there was persistently sterile urine in only eight patients (17%), 32 had occasional and seven had persistent bacteriuria. Escherichia coli was the commonest organism (76.6%) followed by Klebsiella pneumonia (15.7%); 54% of E. coli and 38% of K. pneumonia infections were sensitive to nitrofurantoin. Diurnal continence was achieved in 98% of the patients at 6 months after surgery. There was a gradual decrease in the frequency of nocturnal enuresis (NE) with time, from 87%, to 42%, 28% and 27% at 1, 6, 12 and 18 months, respectively. There was a significant correlation between the presence of bacteriuria and NE during the first 6 months, but it was not sustained after that. The age of the patients was also related significantly to the incidence of NE; at 6 months, only one of 18 men aged < or = 50 years had NE, while 19 of 29 aged > 50 years had (P < 0.001). At 1 year all patients aged < or = 50 years were nocturnally continent, while half of those aged > 50 years had NE (P = 0.001).

CONCLUSIONS

Ileal neobladders are associated with a high incidence of asymptomatic bacteriuria during the first year after surgery. There was spontaneous clearance of bacteriuria with time, with no antimicrobial manipulation. Soon after surgery there was a significant association between bacteriuria and NE. The effect of antimicrobials on patients with NE should be evaluated.

Lymph node involvement in patients with bladder cancer treated with radical cystectomy: a patho-anatomical study--a single center experience

PURPOSE

To our knowledge the extent of lymphadenectomy with cystectomy, the number of lymph nodes to be retrieved and the anatomical groups to be dissected are still undetermined. This study was done to clarify these issues.

MATERIALS AND METHODS

A total of 200 patients underwent radical cystectomy and extended lymphadenectomy up to the level of origin of the inferior mesenteric artery. Removed tissues were labeled according to anatomical location and sent separately for pathological evaluation. In each group the number and status of lymph nodes were determined. The number of positive nodes was correlated with the number of retrieved nodes. Cases with a single positive node were identified and the anatomical location was defined.

RESULTS

The mean number of retrieved nodes per patient +/- SE was 50.6 +/- 14.4 and 48 (24%) patients had nodal disease. The mean number of positive nodes per involved case was 8.08 +/- 13.2. There was a weak correlation between the number of positive nodes and the number of harvested nodes. Bilateral disease was noted in 39.6% of cases. Single node involvement was observed in 22 cases, of which all except 1 were in the endopelvic region.

CONCLUSIONS

There is a sentinel region, which is the endopelvic region (that is the internal iliac and obturator groups of lymph nodes). There are no skipped lesions. Negative nodes in the endopelvic region indicate that more proximal dissection is not necessary. Bilateral endopelvic dissection is mandatory.

SECONDARY MALIGNANT INVOLVEMENT OF GYNECOLOGIC ORGANS IN RADICAL CYSTECTOMY SPECIMENS IN WOMEN: IS IT MANDATORY TO REMOVE THESE ORGANS ROUTINELY?

PURPOSE

We report the incidence of concomitant secondary malignancy of gynecologic organs (uterus, ovaries and vagina) and the incidence of benign lesions affecting these organs in female radical cystectomy specimens.

MATERIALS AND METHODS

Between January 1983 and December 2001, 2,055 radical cystectomies were performed, including 609 in females. Pathological findings in gynecologic organs in female cystectomy specimens were reviewed. These data were correlated with different tumor characteristics.

RESULTS

Mean age of the female patients +/- SD was 47 +/- 9 years (range 20 to 73). Mean followup was 4.3 +/- 4.2 years (range 0.5 to 19). Of these women 390 (64%) had squamous cell bladder carcinoma. Gynecologic organ involvement was documented in 16 of 609 patients (2.6%). Benign ovarian lesions (49 cases or 8%), a simple serous cyst (31), a dermoid cyst (1), a hemorrhagic cyst (3), bilharzial granuloma (6) and corpus albicans (8) were detected. Benign uterine lesions (30 cases or 5%), endometrial hyperplasia (20), endometriosis (4) and fibroids (6) were diagnosed. No primary genital cancers were detected in this study. Gynecologic organ involvement was more frequent in high grade tumors and the transitional cell cancer type than low grade tumors and the squamous cell type (p = 0.01 and 0.05, respectively). Posterior wall tumors were more frequently associated with genital involvement than other sites, although the difference was not statistically significant.

CONCLUSIONS

Evidence is provided that the risk of secondary malignant involvement of genital organs in female cystectomy specimens is low. This low risk together with the low risk of primary cancers of genital organs in this group of patients does not strongly support the routine removal of uninvolved gynecologic organs during radical cystectomy in women.

Continent cutaneous ileal pouch using the serous lined extramural valves. The Mansoura experience in more than 100 patients

PURPOSE

We report on the functional results of continent ileal reservoir using serous lined extramural valves for reflux prevention and continent urinary outlet.

MATERIALS AND METHODS

The procedure was performed in 109 patients (68 men, 27 women and 14 children). The operation was indicated as a primary procedure in 93 patients and for conversion in 16. The technique entailed construction of a detubularized W-shaped ileal reservoir in which 2 serous lined troughs were created. Two tapered ileal segments were used, 1 for reflux prevention and the other as a continent outlet. The appendix was used for the construction of the outlet in 44 patients.

RESULTS

Two patients died in the hospital of pulmonary embolism. A total of 22 early complications were observed in 18 patients (16.5%). None of the patients required operative intervention. A total of 93 patients were evaluable with a mean followup of 36.6 +/- 25.4 months. All evaluable patients but 5 were continent day and night. Mean time for catheterization was 4 to 5 hours. There were 14 late complications reported in 11 patients (11.8%), including pouch stones in 5, stomal stenosis in 5, failure to catheterize in 2, parastomal hernia in 1 and adhesive bowel obstruction in 1. Upper urinary tract was stable or improved in 94.8% of the renal units. Clinical acidosis did not develop in any of the patients.

CONCLUSIONS

Serous lined unidirectional valves are reliable. They provide a versatile surgical technique suitable for urinary diversion or conversion procedures. The operation is associated with an acceptable complication rate and is followed by good functional results.

Nodal involvement in bladder cancer cases treated with radical cystectomy: incidence and prognosis

PURPOSE

We studied the factors that promote the incidence of nodal metastasis and characterized survival predictions in cases treated with radical cystectomy.

MATERIALS AND METHODS

We retrospectively studied 418 bladder cancer cases treated with radical cystectomy and bilateral endopelvic lymphadenectomy. The incidence of nodal involvement was correlated with several patient and tumor characteristics. The number of involved nodes was also correlated with the number of retrieved nodes. Finally, survival in node positive cases was correlated with some select pathological features.

RESULTS

Of the 418 cases nodal involvement was reported in 110 (26.3%). The mean number of harvested nodes per patient +/- SE was 17.9 +/- 6.7. The mean number of positive nodes per involved case was 4.1 +/- 5.4. A weak correlation between the number of retrieved nodes and number of positive nodes was noted (r = 0.4). Tumor pT stage and grade, and lymphovascular invasion were independent factors promoting the incidence of nodal involvement. Three-year disease-free survival in node positive cases was 37.8% +/- 4.8%. Two factors had an independent impact on survival in node positive cases, namely pT stage and the number of positive nodes.

CONCLUSIONS

Tumor pT stage and grade, and lymphovascular invasion independently influence the incidence of lymph node involvement. There was a weak correlation between the number of retrieved nodes and number of positive nodes. The survival probability in pT N+ cases depended on pT stage and the number of involved nodes. A prospective study with anatomical mapping of retrieved nodes is necessary to define the optimal extent of lymphadenectomy with cystectomy.

Local Urethral Recurrence After Radical Cystectomy and Orthotopic Bladder Substitution in Women:: A Prospective Study

PURPOSE

We prospectively studied the pathological outcome and incidence of urethral recurrence after radical cystectomy and orthotopic bladder substitution in women.

MATERIALS AND METHODS

Between January 1995 and December 2001, 145 women with a mean age of 50 +/- 8.5 years underwent standard radical cystectomy and orthotopic substitution for bladder cancer. Histopathological examination of the cystectomy specimens was assessed by a single pathologist. Clinically evident pelvic lymphadenopathy, bladder neck and/or vaginal wall involvement, or positive intraoperative frozen section from the urethra were considered contraindications.

RESULTS

One patient died postoperatively of a massive pulmonary embolism. Followup was 12 to 97 months (mean 36, median 55.8). Pathological stage was P1, P2 (superficial muscle invasion), P3a (deep muscle invasion), P3b (perivesical fat infiltration) and P4a in 12, 29, 56, 44 and 4 patients, respectively. Grade was G1 in 61 patients, G2 in 62 and G3 in 22. Lymph nodes were positive in 28 cases and negative in 117. Histopathology of the trigone revealed carcinoma in situ in 11 cases and squamous metaplasia in 7, while results were free of disease in the remainder. At followup isolated urethral recurrence developed in 2 patients (1.4%), in whom definitive pathological findings showed P3a N1 (positive iliac lymph nodes) M0, grade 2 squamous cell carcinoma in 1 and P3b N0M0 tumor associated with trigonal carcinoma in situ in 1. Local pelvic recurrence developed in 18 patients, distant metastasis developed in 6 and the 2 conditions developed in 10. Oncological failure positively correlated with high stage, high grade and positive lymph nodes.

CONCLUSIONS

The rate of urethral recurrence after radical cystectomy and orthotopic bladder substitution in women is low and acceptable and, thus, it justifies the continued performance of this type of diversion. Proper selection of cases is mandatory. Close followup for oncological failure in this group of patients after cystectomy is necessary.

Outcome of patients with continent urinary reconstruction and a solitary functioning kidney

OBJECTIVE

To evaluate the outcome of patients with continent urinary diversions who had a solitary functioning kidney at the time of surgery.

PATIENTS AND METHODS

In all, 62 patients with continent urinary reservoirs and a solitary functioning kidney were reviewed (51 men and 11 women). The indications for surgery were bladder cancer in 54 and a contracted bladder in eight. The surgical procedures included an orthotopic ileal neobladder in 36 patients, a continent cutaneous ileal reservoir in 13 and rectal diversion in 13. Kidneys were evaluated using serum creatinine level, ultrasonography, intravenous urography and other radiological studies.

RESULTS

The follow-up was 6-173 months; 44 renal units (71%) remained stable during this period. Serum creatinine was increased in four patients with an orthotopic neobladder, with no evidence of obstruction or reflux, in one with preoperative renal impairment and one with voiding dysfunction, reflux and bacteriuria. Six renal units deteriorated because of uretero-intestinal strictures; of these patients, two were treated endoscopically, two with open ureteric reimplantation, one with conversion from a rectal reservoir to an ileal loop conduit, and one was maintained on JJ stenting. Six patients with a rectal diversion had renal deterioration because of chronic pyelonephritis.

CONCLUSIONS

A regular follow-up of renal function is mandatory in patients with a continent urinary diversion. Rectal diversion is associated with a higher risk of renal deterioration (54%) than are orthotopic (28%) and cutaneous reservoirs (8%).

Late uro-ileal cancer after incorporation of ileum into the urinary tract

PURPOSE

Development of late uro-intestinal malignancy after bowel incorporation into the urinary tract is a constant long-term hazard, even in the absence of fecal material. We report 6 such cases.

MATERIALS AND METHODS

A total of 350 patients treated with an ileal conduit, 260 with ileal replacement of the ureter and 55 with ileocystoplasty were evaluated and followed for a minimum of 4 years. The methods of evaluation included urine analysis for microscopic hematuria, urine culture, serum creatinine and abdominal ultrasonography. These evaluations were performed every 2 months after cystectomy for bladder cancer and every 6 months in other cases. Annual urinary cytology and excretory urography were done. Computerized tomography and/or magnetic resonance imaging was performed annually after radical cystectomy or if there was evidence of hematuria, ureteral obstruction or a filling defect in the bladder, pouch or conduit on excretory urography. Endoscopic evaluation was done in some cases. If malignancy was diagnosed chest x-ray and bone scintigraphy were performed.

RESULTS

A total of 645 patients were evaluable. Of these patients late cancer developed at the uro-intestinal anastomotic site in 6 (0.9%), including 1 of 348 (0.3%) who underwent ileal conduit, 3 of 54 (5.5%) ileocystoplasty and 2 of 258 (0.8%) ileal replacement of ureter. The latent period "from the time of original surgery till the development of cancer" ranged from 4 to 32 years (mean plus or minus standard deviation 20.2 +/- 10.9). The pathological type of cancer was adenocarcinoma in 3 patients, transitional cell carcinoma 2 and squamous cell carcinoma 1.

CONCLUSIONS

Late uro-intestinal malignancy in patients who underwent ileal incorporation in the urinary tract is a low but still distinct risk. Ileocystoplasty is more vulnerable to late uro-enteric cancer than ileal conduit and ileal replacement of ureter. Late malignancy can develop earlier than 10 years postoperatively. Therefore, annual surveillance by routine urine cytology postoperatively is advocated, particularly with enterocystoplasty.

Phenylephrine does not limit myocardial blood flow or oxygen delivery during isoflurane-induced hypotension in dogs

Experiments were performed on seven fentanyl-pentobarbital-anesthetized, open-chest dogs to determine whether stimulation of coronary alpha 1-adrenergic receptors by phenylephrine causes coronary vasoconstriction and impaired myocardial oxygen delivery when phenylephrine is infused to correct isoflurane-induced hypotension. Myocardial blood flow was measured with radioactive microspheres, and myocardial oxygen and lactate extraction were determined. The Fick equation was used to calculate myocardial oxygen consumption. Measurements were obtained (a) under control conditions, (b) after a 30-min inhalation of isoflurane sufficient to decrease mean aortic pressure by 30%, and (c) while maintaining administration of isoflurane, 5-10 min after restoration of mean aortic pressure by intravenous infusion of phenylephrine. Isoflurane-induced hypotension was accompanied by a baroreceptor-mediated increase in heart rate and by a decrease in myocardial oxygen consumption; however, myocardial blood flow was maintained, resulting in decreased oxygen extraction and increased coronary sinus PO2, thus implying a direct coronary vasodilating effect for isoflurane. Lactate extraction was unaffected. Phenylephrine infusion during inhalation of isoflurane returned mean aortic pressure and heart rate to their respective control values, and it did not change myocardial oxygen consumption, myocardial blood flow, myocardial oxygen extraction, coronary sinus PO2, or lactate extraction from values obtained during isoflurane alone. These latter findings are consistent with undiminished coronary vasodilation by isoflurane in the presence of phenylephrine. In conclusion, infused phenylephrine to restore aortic pressure during isoflurane administration had no vasoconstrictor effect in the coronary circulation and did not impair myocardial oxygen delivery. Apparently, the direct coronary vasodilating action of isoflurane completely nullified phenylephrine-induced vasoconstriction via local alpha 1-adrenergic receptors.