David Rix

NONINVASIVE MEASUREMENT OF BLADDER PRESSURE BY CONTROLLED INFLATION OF A PENILE CUFF

PURPOSE A noninvasive test providing reliable objective quantification of bladder pressure during the voiding cycle would make an important contribution to the management of lower urinary tract symptoms. We developed a new noninvasive test to measure bladder pressure in males based on controlled inflation of a penile cuff during voiding. We compared the new technique with simultaneous invasive bladder pressure measurement. MATERIALS AND METHODS We evaluated 7 volunteers and 32 patients. A conventional pressure flow study was performed first. The bladder was refilled, a penile cuff was fitted and after voiding commenced the cuff was inflated in steps of 10 cm. water every 0.75 seconds until urine flow was interrupted. The cuff was rapidly deflated, allowing flow to resume, and the cycle was repeated until the end of voiding. The flow rate was graphed against cuff pressure for each interruption cycle to determine the pressure at which flow was interrupted. This pressure was compared with simultaneous invasive isovolumetric bladder pressure. RESULTS Invasive and noninvasive pressure measurements agreed well. Average cuff pressure at interruption of flow exceeded mean simultaneous isovolumetric bladder pressure plus or minus standard deviation by 14.5 +/- 14.0 cm. water. CONCLUSIONS The new method provides noninvasive quantitative information on voiding bladder pressure in males. Further study is required to assess whether the technique can contribute to the management of lower urinary tract symptoms.

Routine Intraoperative Stenting for Renal Transplant Recipients

Background. Major urological complications (MUCs) after kidney transplantation contribute to patient morbidity and compromise graft function. Ureteric stents have been successfully used to treat such complications and a number of centers have adopted a policy of universal prophylactic stenting, at the time of graft implantation, to reduce the incidence of urine leaks and ureteric stenosis. Methods. In conjunction with the Cochrane Renal Group we searched the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, reference lists of articles, books and abstracts and contacted companies, authors and experts to identify randomized controlled trials examining the use of stents in renal transplantation. The primary outcome was the incidence of MUCs and data on this statistic was pooled and analyzed using a random effects model. Results. Seven randomized controlled trials (1154 patients) of low or moderate quality were identified. The incidence of MUCs was significantly reduced (relative risk [RR] 0.24; 95% CI: 0.07 - 0.77; P=0.02; number needed to treat = 13) by prophylactic ureteric stenting. Urinary tract infections were more common in stented patients (RR 1.49), unless the patients were prescribed 480 mg cotrimoxazole once daily. With this antibiotic regime the incidence of infection was equivalent between the two groups (RR 0.97). Stents appeared generally well tolerated, although trials using longer stents (≥20 cm) for longer periods of time (>6 weeks) reported more problems with encrustation and migration. Conclusions. Universal prophylactic stenting reduces the incidence of MUCs and should be recommended on the basis of currently available randomized controlled trials.

Prospective study comparing three-dimensional computed tomography and magnetic resonance imaging for evaluating the renal vascular anatomy in potential living renal donors

To prospectively compare the accuracy of multislice spiral computed tomographic angiography (CTA) and magnetic resonance angiography (MRA) in evaluating the renal vascular anatomy in potential living renal donors.

Comparison of laparoscopic and open donor nephrectomy: UK experience.

A comparison of laparoscopic and open donor nephrectomy is presented by authors from the UK. They found that the laparoscopic approach could safely be offered to patients treated in experienced units and after adequate training fo the surgeon, with no increase in complications or decrease in efficacy.

The management of transitional cell carcinoma (TCC) in a European regional renal transplant population.

Study Type – Therapy (prospective cohort)

Donation after Cardiac Death Kidneys with Low Severity Pre‐Arrest Acute Renal Failure

The widening gap between supply and demand for renal transplantation has prompted many centers to use donors after cardiac death. Some of these donors exhibit signs of acute renal failure (ARF) prior to cardiac arrest. Concern has been expressed about poor quality of graft function from such donors. In response to this perception, we reviewed 49 single renal transplant recipients from category III donors after cardiac death between 1998 and 2005, at out center. All kidneys but one had hypothermic machine perfusion and viability testing prior to transplantation. According to the RIFLE criteria, nine recipients had kidneys from donors with “low severity pre‐arrest ARF”. The remainder of the recipients were used as control group. There was no statistical significant difference in delayed graft function and rejection rates between these two groups. Recipients GFR at 12 months was 44.4 ± 17.1 and 45.2 ± 14.7 (mL/min/1.73m2) from donors with ARF and without ARF, respectively (p = 0.96). In conclusion, low severity ARF in kidneys from controlled after cardiac death donors can be a reversible condition after transplantation. Short‐term results are comparable to the kidneys from same category donors without renal failure, providing that some form of viability assessment is implemented prior to transplantation.

Ischemia-Reperfusion Injury in Cadaveric Nonheart Beating, Cadaveric Heart Beating and Live Donor Renal Transplants

PURPOSE Ischemia-reperfusion injury is gaining importance in transplantation as being responsible for allograft dysfunction. Ischemia occurs during kidney procurement, which is shortest in LDs, and prolonged in cadaveric HBDs and NHBDs. MATERIALS AND METHODS Renal transplants from 17 LDs, 15 HBDs and 19 NHBDs were assessed during reperfusion for biochemical markers of ischemia-reperfusion injury and assessed clinically. Central venous blood sampling was assayed for free radicals using electron spin resonance and tissue injury biomarkers, namely lactate dehydrogenase, fatty acid binding protein, alanine aminopeptidase, lactate and total antioxidants. RESULTS The return to stable renal function was more rapid in LD renal transplants, while recovery continued from 3 months after hospital discharge in NHBD renal transplants. Injury markers, such as lactate dehydrogenase, fatty acid binding protein, alanine aminopeptidase and lactate, were raised at the time of reperfusion, especially in NHBD renal transplants. Free radical release measured by electron spin resonance showed 2 phase release, that is early (0 to 10-minute) and late (20 to 40-minute) release. In NHBD, HBD and LD renal transplants the index of free radical release in the early phase was 1.43, 1.36 and 1.20, and in the late phase it was 1.43, 1.38 and 0.97, respectively (each ANOVA p <0.05). CONCLUSIONS NHBD renal transplants were accompanied by a greater release of free radicals at reperfusion (NHBD > HBD > LD), which was associated with an increase in tissue injury markers at reperfusion. This was reflected in a slower return to stable renal function in NHBD compared to HBD and LD renal transplants.

Can the R.E.N.A.L Nephrometry Score Preoperatively Predict Postoperative Clinical Outcomes in Patients Undergoing Open and Laparoscopic Partial Nephrectomy

Aim: We evaluate whether the preoperative R.E.N.A.L Nephrometry Score (RNS) can predict the postoperative outcomes in patients undergoing either an open or laparoscopic partial nephrectomy. Patients and Methods: We retrospectively calculated the RNS of 128 patients who underwent either an open partial nephrectomy (OPN) (n = 38) or laparoscopic partial nephrectomy (LPN) (n = 90) between 2003 and 2011. Patients were categorized into low, moderate or high complexity groups based on RNSs. Intra-operative warm ischemic time (WIT), peri-operative surgical outcomes using the Clavien-Dindo classification, postoperative histology, positive surgical margin rates were correlated to the RNS. Results: The RNS was associated with the length of the WIT in OPN (low vs. moderate vs. high: 11.4 vs. 13.1 vs. 23.4 minutes, p = 0.025) and blood loss in LPN (low vs. moderate 319 vs. 498 ml, p = 0.009). The positive surgical margins were greater in high versus moderate RNS lesions (40 vs. 7.4%, p = 0.045). No differences were seen in complications, hospital stay or transfusion rates. The RNS was significantly higher in OPN versus LPN (7.45 vs. 6.2, p = 0.0002). Conclusion: An Increasing RNS was associated with increased WIT in OPN and blood loss in LPN, supporting RNS relationship to tumor complexity. A higher RNS in OPN indicate it may corroborate procedure choice. RNS should allow comparisons between treatment modalities for similar complexity lesions and with further research could aid stratification of individual risk preoperatively.

Endourological Management of Urolithiasis in Donor Kidneys prior to Renal Transplant.

Background. We present our centres successful endourological methodology of ex vivo ureteroscopy (EVFUS) in the management of these kidneys prior to renal transplantation. Patient and Methods. A retrospective analysis was performed of all living donors (n = 157) identified to have asymptomatic incidental renal calculi from January 2004 until December 2008. The incidence of asymptomatic renal calculi was 3.2% (n = 5). Donors were subdivided into 2 groups depending on whether theydonated the kidney with the renal calculus (Group 1) versus the opposite calculus-free kidney (Group 2). Results. All donors in Group 1 underwent a left laparoscopic donor nephrectomy. The calculi were extracted in all 3 cases using a 7.5 Fr flexible ureteroscope either prior to transplant (n = 2) or on revascularization (n = 1). There were no urological complications in either group. At a mean followup at 64 months there was no recurrent calculi formation in the recipient in Group 1. However, 1 recipient formed a calculus in group 2 at a follow up of 72 months. Conclusions. Renal calculi can be successfully retrieved during living-related transplantation at the time of transplant itself using EVUS. This is technically feasible and is associated with no compromise in ureteral integrity or renal allograft function.

Renal Transplantation with Kidneys Affected by Tumours

Renal transplantation confers improvement in quality of life and survival when compared to patients on dialysis. There is a universal shortage of organs, and efforts have been made to overcome this shortage by exploring new sources. One such area is the use of kidneys containing small tumours after resection of the neoplasm. This paper looks at the current evidence in the literature and reviews the feasibility of utilizing such a source.