Hypertension and Kidney Function After Living Kidney Donation.

Importance: Recent guidelines call for better evidence on health outcomes after living kidney donation. Objective: To determine the risk of hypertension in normotensive adults who donated a kidney compared with nondonors of similar baseline health. Their rates of estimated glomerular filtration rate (eGFR) decline and risk of albuminuria were also compared. Design, Setting, and Participants: Prospective cohort study of 924 standard-criteria living kidney donors enrolled before surgery and a concurrent sample of 396 nondonors. Recruitment occurred from 2004 to 2014 from 17 transplant centers (12 in Canada and 5 in Australia); follow-up occurred until November 2021. Donors and nondonors had the same annual schedule of follow-up assessments. Inverse probability of treatment weighting on a propensity score was used to balance donors and nondonors on baseline characteristics. Exposure: Living kidney donation. Main Outcomes and Measures: Hypertension (systolic blood pressure [SBP] ≥140 mm Hg, diastolic blood pressure [DBP] ≥90 mm Hg, or antihypertensive medication), annualized change in eGFR (starting 12 months after donation/simulated donation date in nondonors), and albuminuria (albumin to creatinine ratio ≥3 mg/mmol [≥30 mg/g]). Results: Among the 924 donors, 66% were female; they had a mean age of 47 years and a mean eGFR of 100 mL/min/1.73 m2. Donors were more likely than nondonors to have a family history of kidney failure (464/922 [50%] vs 89/394 [23%], respectively). After statistical weighting, the sample of nondonors increased to 928 and baseline characteristics were similar between the 2 groups. During a median follow-up of 7.3 years (IQR, 6.0-9.0), in weighted analysis, hypertension occurred in 161 of 924 donors (17%) and 158 of 928 nondonors (17%) (weighted hazard ratio, 1.11 [95% CI, 0.75-1.66]). The longitudinal change in mean blood pressure was similar in donors and nondonors. After the initial drop in donors' eGFR after nephrectomy (mean, 32 mL/min/1.73 m2), donors had a 1.4-mL/min/1.73 m2 (95% CI, 1.2-1.5) per year lesser decline in eGFR than nondonors. However, more donors than nondonors had an eGFR between 30 and 60 mL/min/1.73 m2 at least once in follow-up (438/924 [47%] vs 49/928 [5%]). Albuminuria occurred in 132 of 905 donors (15%) and 95 of 904 nondonors (11%) (weighted hazard ratio, 1.46 [95% CI, 0.97-2.21]); the weighted between-group difference in the albumin to creatinine ratio was 1.02 (95% CI, 0.88-1.19). Conclusions and Relevance: In this cohort study of living kidney donors and nondonors with the same follow-up schedule, the risks of hypertension and albuminuria were not significantly different. After the initial drop in eGFR from nephrectomy, donors had a slower mean rate of eGFR decline than nondonors but were more likely to have an eGFR between 30 and 60 mL/min/1.73 m2 at least once in follow-up. Trial Registration: ClinicalTrials.gov Identifier: NCT00936078.

Gestational hypertension and preeclampsia in living kidney donors.

BACKGROUND: Young women wishing to become living kidney donors frequently ask whether nephrectomy will affect their future pregnancies. METHODS: We conducted a retrospective cohort study of living kidney donors involving 85 women (131 pregnancies after cohort entry) who were matched in a 1:6 ratio with 510 healthy nondonors from the general population (788 pregnancies after cohort entry). Kidney donations occurred between 1992 and 2009 in Ontario, Canada, with follow-up through linked health care databases until March 2013. Donors and nondonors were matched with respect to age, year of cohort entry, residency (urban or rural), income, number of pregnancies before cohort entry, and the time to the first pregnancy after cohort entry. The primary outcome was a hospital diagnosis of gestational hypertension or preeclampsia. Secondary outcomes were each component of the primary outcome examined separately and other maternal and fetal outcomes. RESULTS: Gestational hypertension or preeclampsia was more common among living kidney donors than among nondonors (occurring in 15 of 131 pregnancies [11%] vs. 38 of 788 pregnancies [5%]; odds ratio for donors, 2.4; 95% confidence interval, 1.2 to 5.0; P=0.01). Each component of the primary outcome was also more common among donors (odds ratio, 2.5 for gestational hypertension and 2.4 for preeclampsia). There were no significant differences between donors and nondonors with respect to rates of preterm birth (8% and 7%, respectively) or low birth weight (6% and 4%, respectively). There were no reports of maternal death, stillbirth, or neonatal death among the donors. Most women had uncomplicated pregnancies after donation. CONCLUSIONS: Gestational hypertension or preeclampsia was more likely to be diagnosed in kidney donors than in matched nondonors with similar indicators of baseline health. (Funded by the Canadian Institutes of Health Research and others.).

Duration of Living Kidney Transplant Donor Evaluations: Findings From 2 Multicenter Cohort Studies.

BACKGROUND: A prolonged living kidney donor evaluation may result in worse outcomes for transplant recipients. Better knowledge of the duration of this process may help inform future donors and identify opportunities for improvement. STUDY DESIGN: 1 prospective and 1 retrospective cohort study. SETTING & PARTICIPANTS: At 16 Canadian and Australian transplantation centers (prospective cohort) and 5 Ontario transplantation centers (retrospective cohort), we assessed the duration of living kidney donor evaluation and explored donor, recipient, and transplantation factors associated with longer evaluation times. Data were obtained from 2 sources: donor medical records using chart abstraction and health care administrative databases. PREDICTORS: Donor and recipient demographics, direct versus paired donation, center-level variables. OUTCOMES: Duration of living donor evaluation. RESULTS: The median total duration of transplantation evaluation (time from when the candidate started the evaluation until donation) was 10.3 (IQR, 6.5-16.7) months. The median duration from evaluation start until approval to donate was 7.9 (IQR, 4.6-14.1) months, and from approval until donation was 0.7 (IQR, 0.3-2.4) months, respectively. The median time between the first and last consultation among donors who completed a nephrology, surgery, and psychosocial assessment in the prospective cohort was 3.0 (IQR, 1.0-6.3) months, and between computed tomography angiography and donation was 4.8 (IQR, 2.6-9.2) months. After adjustment, the total duration of transplantation evaluation was longer if the donor participated in paired donation (6.6 [95% CI, 1.6-9.7] months) and if the recipient was referred later relative to the donor's evaluation start date (0.9 [95% CI, 0.8-1.0] months [per month of delayed referral]). Results depended on whether the recipient was receiving dialysis. LIMITATIONS: Living donor candidates who did not donate were not included and proxy measures were used for some dates in the donor evaluation process. CONCLUSIONS: The duration of kidney transplant donor evaluation is variable and can be lengthy. Better understanding of the reasons for a prolonged evaluation may inform quality improvement initiatives to reduce unnecessary delays.

Accuracy of portrayal by standardized patients: results from four OSCE stations conducted for high stakes examinations.

BACKGROUND: The reliability in Objective Structured Clinical Exams (OSCEs) is based on variance introduced due to examiners, stations, items, standardized patients (SP), and the interaction of one or more of these items with the candidates. The impact of SPs on the reliability has not been well studied. Accordingly, the main purpose of the present study was to assess the accuracy of portrayal by standardized patients. METHODS: Four stations from a ten station high-stakes OSCE were selected for video recording. Due to the large number of candidates to be evaluated, the OSCE was administered using four assessment tracks. Four SPs were trained for each case (n = 16). Two physician assessors were trained to assess the accuracy of SP portrayal using a station-specific instrument based on the station guidelines. For the items with disagreement a third physician was asked to review and the mode was used for analysis. Each instrument included case-specific items on verbal and physical portrayal using a 3-point rating scale ("yes", "yes, but" and "not done"). The physician assessors also scored each SP on their overall performance based on a 5-item anchored global rating scale ("very poor", "poor", "ok", "good", and "very good"). SPs at location 1 were trained by one trainer and SPs at location 2 had another trainer. All SPs were employed in a high-stakes OSCE for at least the second time. RESULTS: The reliability of rating scores ranged from Cronbach's alpha of .40 to .74. Verbal portrayal by SPs did not significantly differ for most items; however, the facial expressions of the SPs differed significantly (p < .05). An emergency management station that depended heavily on SPs physical presentation and facial expressions differed between all four SPs trained for that station. CONCLUSIONS: Variation of trained SP portrayal of the same station across different tracks and at different times in OSCE may contribute substantial error to OSCE assessments. The training of SPs should be strengthened and constantly monitored during the exam to ensure that the examinees' scores are a true reflection of their competency and devoid of exam errors.

Fracture risk in living kidney donors: a matched cohort study.

BACKGROUND: Chronic kidney disease increases the risk of bone fragility fractures (osteoporotic fractures). Living kidney donors lose 50% of their renal mass and show changes in calcium homeostasis. We studied whether living kidney donation increases the risk of fragility fracture. DESIGN: Retrospective matched-cohort study. SETTING & PARTICIPANTS: We reviewed the medical charts of all 2,015 adults in Ontario, Canada, who donated a kidney between 1992 and 2009 (surgeries performed across 5 transplant programs). We linked this information to health care databases and randomly selected 20,150 matched nondonors from the healthiest portion of the general population. Median age was 43 (95% CI, 24-50) years at study enrollment. Donors and nondonors were then followed up for a median of 6.6 years and a maximum of 17.7 years. PREDICTOR: Living donor nephrectomy. OUTCOMES: The primary outcome was lower- and upper-extremity fragility fractures. Individuals who reached 66 years or older in follow-up had bisphosphonate prescriptions recorded. RESULTS: The rate of fragility fracture was no higher in donors compared with nondonors (16.4 vs 18.7 events/10,000 person-years; rate ratio, 0.88; 95% CI, 0.58-1.32). Results were similar in multiple additional analyses. There was little difference in the proportion of older adults in follow-up who received a bisphosphonate prescription (17.1% vs 15.2%; P = 0.4). LIMITATIONS: These are interim results. Ongoing surveillance of this and other donor cohorts is warranted to be sure an association does not manifest with longer follow-up. CONCLUSIONS: To date, there is no evidence of increased fragility fracture risk in living kidney donors. Our results meet an information need and are reassuring for the safety of the practice.

The Living Kidney Donor Safety Study: Protocol of a Prospective Cohort Study.

Background: Living kidney donation is considered generally safe in healthy individuals; however, there is a need to better understand the long-term effects of donation on blood pressure and kidney function. Objectives: To determine the risk of hypertension in healthy, normotensive adults who donate a kidney compared with healthy, normotensive non-donors with similar indicators of baseline health. We will also compare the 2 groups on the rate of decline in kidney function, the risk of albuminuria, and changes in health-related quality of life. Design Participants and Setting: Prospective cohort study of 1042 living kidney donors recruited before surgery from 17 transplant centers (12 in Canada and 5 in Australia) between 2004 and 2014. Non-donor participants (n = 396) included relatives or friends of the donor, or donor candidates who were ineligible to donate due to blood group or cross-match incompatibility. Follow-up will continue until 2021, and the main analysis will be performed in 2022. The anticipated median (25th, 75th percentile, maximum) follow-up time after donation is 7 years (6, 8, 15). Measurements: Donors and non-donors completed the same schedule of measurements at baseline and follow-up (non-donors were assigned a simulated nephrectomy date). Annual measurements were obtained for blood pressure, estimated glomerular filtration rate (eGFR), albuminuria, patient-reported health-related quality of life, and general health. Outcomes: Incident hypertension (a systolic/diastolic blood pressure ≥ 140/90 mm Hg or receipt of anti-hypertensive medication) will be adjudicated by a physician blinded to the participant's donation status. We will assess the rate of change in eGFR starting from 12 months after the nephrectomy date and the proportion who develop an albumin-to-creatinine ratio ≥3 mg/mmol (≥30 mg/g) in follow-up. Health-related quality of life will be assessed using the 36-item RAND health survey and the Beck Anxiety and Depression inventories. Limitations: Donation-attributable hypertension may not manifest until decades after donation. Conclusion: This prospective cohort study will estimate the attributable risk of hypertension and other health outcomes after living kidney donation.

Contexte: Chez les personnes en bonne santé, faire don d'un rein est généralement considéré comme sûr. Il convient toutefois de mieux comprendre les effets à long terme de ce don sur la pression artérielle et la fonction rénale. Objectifs: Déterminer le risque d'hypertension chez les adultes sains et normotendus qui donnent un rein par rapport à des non-donneurs sains et normotendus ayant des indicateurs de santé de base similaires. Nous comparerons également le taux de réduction de la fonction rénale, le risque d'albuminurie et les changements dans la qualité de vie liée à la santé entre les deux groupes. Cadre type d'étude et participants: Étude de cohorte rétrospective menée sur 1 042 donneurs de rein vivants, recrutés avant la chirurgie dans 17 centres de transplantation (12 au Canada et 5 en Australie) entre 2004 et 2014. Le groupe des non-donneurs (n=396) était constitué de parents ou amis du donneur, ou de candidats donneurs non admissibles à faire un don en raison d'une incompatibilité de groupe sanguin ou lors du test de compatibilité croisée. Le suivi s'est poursuivi jusqu'en 2021 et l'analyse principale sera effectuée en 2022. Le temps de suivi médian prévu (25e percentile, 75e percentile, maximum) après le don est de 7 ans (6, 8, 15 ans). Mesures: Les donneurs et les non-donneurs ont complété le même calendrier de mesures à l'inclusion et pendant le suivi (une date simulée de néphrectomie a été attribuée aux non-donneurs). Des mesures annuelles de pression artérielle, de débit de filtration glomérulaire estimé (DFGe), d'albuminurie, de qualité de vie liée à la santé autodéclarée et de santé générale ont été obtenues. Issues principales: L'hypertension incidente (pression artérielle systolique/diastolique ≥ 140/90 mm Hg ou prise d'un médicament antihypertenseur) sera jugée par un médecin aveugle au statut de don du participant. Nous évaluerons le taux de variation du DFGe à partir de 12 mois après la date de la néphrectomie et la proportion de participants qui développeront un rapport albumine/créatinine ≥ 3 mg/mmol (≥ 30 mg/g) pendant le suivi. La qualité de vie liée à la santé sera évaluée à l'aide du questionnaire de santé RAND de 36 questions et de l'Inventaire d'anxiété et de dépression de Beck. Limites: L'hypertension attribuable au don pourrait ne pas se manifester avant des décennies après le don. Conclusion: Cette étude de cohorte prospective permettra d'estimer le risque d'hypertension attribuable au don et d'autres effets sur la santé du donneur après un don de rein.

Perioperative Complications During Living Donor Nephrectomy: Results From a Multicenter Cohort Study.

BACKGROUND: While living kidney donation is considered safe in healthy individuals, perioperative complications can occur due to several factors. OBJECTIVE: We explored associations between the incidence of perioperative complications and donor characteristics, surgical technique, and surgeon's experience in a large contemporary cohort of living kidney donors. DESIGN: Living kidney donors enrolled prospectively in a multicenter cohort study with some data collected retrospectively after enrollment was complete (eg, surgeon characteristics). SETTING: Living kidney donor centers in Canada (n = 12) and Australia (n = 5). PATIENTS: Living kidney donors who donated between 2004 and 2014 and the surgeons who performed the living kidney donor nephrectomies. MEASUREMENTS: Operative and hospital discharge medical notes were collected prospectively, with data on perioperative (intraoperative and postoperative) information abstracted from notes after enrollment was complete. Complications were graded using the Clavien-Dindo system and further classified into minor and major. In 2016, surgeons who performed the nephrectomies were invited to fill an online survey on their training and experience. METHODS: Multivariable logistic regression models with generalized estimating equations were used to compare perioperative complication rates between different groups of donors. The effect of surgeon characteristics on the complication rate was explored using a similar approach. Poisson regression was used to test rates of overall perioperative complications between high- and low-volume centers. RESULTS: Of the 1421 living kidney donor candidates, 1042 individuals proceeded with donation, where 134 (13% [95% confidence interval (CI): 11%-15%]) experienced 142 perioperative complications (55 intraoperative; 87 postoperative). The most common intraoperative complication was organ injury and the most common postoperative complication was ileus. No donors died in the perioperative period. Most complications were minor (90% of 142 complications [95% CI: 86%-96%]); however, 12 donors (1% of 1042 [95% CI: 1%-2%]) experienced a major complication. No statistically significant differences were observed between donor groups and the rate of complications. A total of 43 of 48 eligible surgeons (90%) completed the online survey. Perioperative complication rates did not vary significantly by surgeon characteristics or by high- versus low-volume centers. LIMITATIONS: Operative and discharge reporting is not standardized and varies among surgeons. It is possible that some complications were missed. The online survey for surgeons was completed retrospectively, was based on self-report, and has not been validated. We had adequate statistical power only to detect large effects for factors associated with a higher risk of perioperative complications. CONCLUSIONS: This study confirms the safety of living kidney donation as evidenced by the low rate of major perioperative complications. We did not identify any donor or surgeon characteristics associated with a higher risk of perioperative complications. TRIAL REGISTRATIONS: NCT00319579: A Prospective Study of Living Kidney Donation (https://clinicaltrials.gov/ct2/show/NCT00319579)NCT00936078: Living Kidney Donor Study (https://clinicaltrials.gov/ct2/show/NCT00936078).

CONTEXTE: Bien que le don vivant d'un rein soit sécuritaire chez un individu en santé, plusieurs facteurs sont susceptibles d'engendrer des complications périopératoires. OBJECTIF: Nous avons exploré l'association entre l'incidence des complications périopératoires et les caractéristiques du donneur, la technique chirurgicale employée et l'expérience du chirurgien au sein d'une vaste cohorte contemporaine de donneurs vivants d'un rein. TYPE D'ÉTUDE: Une étude de cohorte multicentrique où certaines données (notamment les renseignements concernant le chirurgien) ont été recueillies rétrospectivement, après l'inclusion complète des sujets (donneurs vivants d'un rein). CADRE: Des centres de transplantation au Canada (n=12) et en Australie (n=5). SUJETS: Des individus ayant fait don d'un rein entre 2004 et 2014, et les chirurgiens qui ont procédé à la néphrectomie. MESURES: Les notes médicales au dossier, opératoires et à la sortie de l'hôpital, ont été recueillies de façon prospective; les données concernant les renseignements périopératoires (peropératoires et postopératoires) ayant été extraites des notes une fois l'inclusion du sujet complétée. Les complications ont été catégorisées selon la classification de Clavien-Dindo, puis caractérisées comme étant mineures ou majeures. En 2016, les chirurgiens ayant pratiqué les néphrectomies ont été invités à répondre à un sondage en ligne au sujet de leur formation et de leur expérience. MÉTHODOLOGIE: Des modèles de régression logistique multivariée utilisant des équations d'estimation généralisées ont été employés pour comparer les taux de complications périopératoires entre les différents groupes de donneurs. L'effet exercé sur le taux de complications par les caractéristiques du chirurgien a été exploré selon une approche similaire. Une régression de Poisson a été utilisée pour évaluer et comparer les taux globaux de complications entre les centres à volume élevé et les centres à faible volume. RÉSULTATS: Des 1 421 candidats répertoriés, 1 042 individus ont subi une néphrectomie, desquels 134 (13 % [IC 95 %: 11­15 %]) ont vécu un total de 142 complications périopératoires (55 peropératoires; 87 postopératoires). La complication peropératoire la plus fréquente était une lésion à l'organe, alors qu'un iléus s'est avéré la principale complication postopératoire. Aucun donneur n'est décédé en période périopératoire. La plupart des complications rencontrées étaient mineures (90 % des 142 complications répertoriées [IC 95 %: 86­96 %]). Toutefois, 12 donneurs (1 % des 1 042 donneurs [IC 95 %: 1­2 %]) ont souffert de complications majeures. Aucune différence significative du point de vue statistique n'a été observée entre les groupes de donneurs et le taux de complications. Des 48 chirurgiens admissibles, 43 (90 %) ont répondu au sondage en ligne. Les taux de complications périoperatoires n'ont pas varié de façon significative en fonction des caractéristiques des chirurgiens, ou selon le volume de patients de l'hôpital. LIMITES: La façon d'inscrire les renseignements médicaux (opératoires ou à la sortie de l'hôpital) dans les dossiers des patients n'est pas normalisée et varie d'un chirurgien à l'autre. Certaines complications pourraient ne pas avoir été notées. Le sondage en ligne destiné aux chirurgiens a été rempli rétrospectivement, il reposait sur des déclarations volontaires et n'avait pas fait l'objet d'une validation. Nous ne disposions d'une puissance statistique que pour détecter les effets importants des facteurs associés à un risque accru de complications périopératoires. CONCLUSION: Cette étude confirme le caractère sécuritaire d'un don vivant de rein, comme en témoigne le très faible taux de complications périopératoires majeures. Nous n'avons pu établir de caractéristiques, du donneur ou du chirurgien, qui soit associées à un risque accru de complications périopératoires.

Assessment of live kidney donors by magnetic resonance angiography: reliability and impact on outcomes.

BACKGROUND: Kidney allograft retrieval from live donors requires accurate determination of kidney anatomy prior to surgery, particularly the arterial supply. Traditionally, conventional angiography has been used to obtain this information. Magnetic resonance angiography (MRA) offers a non-invasive, cost-effective alternative, but has been considered to be less accurate. Despite this criticism, many centers have moved to MRA screening of potential kidney donors. The objective of this study is to evaluate our experience of the reliability of MRA in determining the arterial anatomy of living kidney donors as compared to the intra-operative findings. METHODS: We performed a retrospective review of gadolinium-enhanced, ultra-fast, three-dimensional, spoiled gradient-echo MRA in live kidney donors in the Southern Alberta Transplant Program and compared these results with the intra-operative findings during nephrectomy, as the gold standard. RESULTS: Of the 66 patients, an accessory renal artery was found intra-operatively in eight cases; two of which were erroneously diagnosed as normal by MRA. The negative predictive value for MRA was 0.97, false-negative rate was 0.25, and sensitivity was 0.75. No patient experienced side-effects from the MRA procedure. No donor needed conversion to open nephrectomy because of an undetected accessory renal artery. One allograft with an accessory renal artery developed thrombosis of the lower pole of the kidney despite arterial reconstruction. Kidney function in the recipient of this allograft was excellent and there was no urinary leak. CONCLUSION: In our hands, MRA determined the vascular anatomy of potential kidney donors with an acceptable negative predictive value of 97%.

Retro-peritoneal cooling for kidney preservation from multi-organ cadaver donors.

BACKGROUND: Minimizing ischemia is paramount in the procurement of kidneys for transplantation. A fast cooling and expeditious removal is ideal to minimize damage from warm ischemia, however, since the removal of kidneys is delayed in cadaver donation until all other organs are harvested, the risk of kidney damage increases due to contact with the warmer soft body tissues. Surgical techniques that expedite organ retrieval were developed to avoid organ damage. METHODS: We test a modification of Thomas Starzl's improved technique for multi-organ harvesting by interposing an ice bag between the posterior aspect of the kidney and the psoas muscle in a randomized trial with 21 multi-organ cadaver donors. RESULTS: The modified technique decreases the extraction temperature of the kidneys significantly in comparison with the controls, p < .001. CONCLUSIONS: This simple technique improves the preservation of kidneys from cadaver donors, and can potentially have more impact on multi-organ donation after cardiac death.

Use of a minimally invasive donor nephrectomy program to select technique for live donor nephrectomy.

BACKGROUND: Live donor nephrectomy (LDN) is a major surgical procedure with an accepted low mortality and morbidity. Minimally invasive donor nephrectomy (MIDN) has been shown to decrease the wound morbidity associated with the lumbotomy of the classic open technique. Transplant programs face the challenge of initiating their MIDN programs without jeopardizing the safety of the donor and the graft quality. We present the experience at the University of Calgary after the initiation of a MIDN program, with a preoperative selective approach using the 3 major techniques for LDN. METHODS: From December 2001 to May 2004, 50 consecutive, accepted, live kidney donors were evaluated and chosen to undergo nephrectomy by an open, laparoscopic, or hand-assisted technique. Patients were chosen for a particular technique based on the criteria of vascular anatomy, size of abdominal cavity, previous surgery, and technical implications for the recipient. RESULTS: A total of 15 open, 11 laparoscopic, and 24 hand-assisted nephrectomies were performed. There were no statistically significant differences in sex, age, or body mass index between the groups. There were statistically significant differences in surgical times (P < .001) and in the number of days spent in the hospital (P < .001). All kidneys had primary function. There were 2 conversions in the hand-assisted group and 1 blood transfusion in the open group. Death-censored graft survival was 100% with an observation time of 20 months (SD +/- 9 months; range = 3-32 months). One graft from the hand-assisted group was lost from patient death with functioning graft 8 months after transplant. CONCLUSIONS: The learning curve for MIDN does not necessarily need to impact donor or recipient outcomes. The initiation of an MIDN program can be implemented safely if the cases are selected carefully and the use of the classic open technique is kept as an alternative.

Independent prediction factors for primary patency loss in arteriovenous grafts within six months.

PURPOSE: The objective of this study was to explore the association between loss of primary functional patency within 6 months of first use and demographic and clinical characteristics in patients with arteriovenous grafts (AVGs) receiving chronic hemodialysis. The knowledge and management of these characteristics will minimize the proportion of catheterdependent dialysis patients for whom AVGs are the best choice. METHODS: This was a retrospective study of all chronic hemodialysis patients with AVGs followed by the Southern Alberta Renal Program from January 2005 to June 2008. Demographic and clinical variables and initial intra-access blood flow (IABF) were compared between those with and without loss of primary functional patency. To determine the contribution of independent variables to the dependant variable of loss of primary functional patency, a multivariable analysis using logistic regression was performed. RESULTS: The incidence of primary failure was 30% (107/359). Multivariable analysis found that low initial IABF (<650 mL/ min, odds ratio [OR] 31, P < 0.001), presence of diabetes (OR 3.5, P = 0.001), older age (>65 years OR 3.2, P< 0.001), and presence of peripheral vascular disease (OR 2.5, P< 0.005) were independently associated with loss of primary patency. CONCLUSIONS: AVGs are sometimes a better choice for those patients in which the time to and probability of successful fistula maturation may be a concern. Close monitoring of AVGs in patients with the identified risk factors associated with loss of primary patency may improve the life expectancy of the access.

Risk factors associated with patency loss of hemodialysis vascular access within 6 months.

BACKGROUND AND OBJECTIVES: Clinical guidelines support vascular access surveillance to detect access dysfunction and alter the clinical course by radiologic or surgical intervention. The objective of this study was to explore the association between loss of primary functional patency within 6 months of first use and demographic and clinical characteristics of patients receiving chronic renal replacement therapy with arteriovenous fistulas. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: This was a retrospective study of all chronic hemodialysis patients followed by the Southern Alberta Renal Program from January 1, 2005 to June 30, 2008. Demographic and clinical variables and initial intra-access blood flow (IABF) were compared between those with and without loss of primary functional patency. To determine the contribution of independent variables to the dependant variable of loss of primary functional patency, a multivariable analysis using logistic regression was performed. RESULTS: The incidence of primary failure was 10% (81 of 831). Multivariable analysis found that older age (>65 years, odds ratio [OR] 3.6, P < 0.001), history of diabetes (OR 2.3, P = 0.007), history of smoking (OR 4.3, P < 0.001), presence of forearm fistulas (OR 4.0, P < 0.001), and low initial IABF (<500 ml/min, OR 29, P < 0.001) were independently associated with loss of primary patency. CONCLUSIONS: The set of patient risk factors identified in this study, particularly initial IABF, can be used to identify patients who are most at risk for developing vascular access failure and to guide a more directed approach for a vascular access screening protocol.

Native arteriovenous fistulas: correlation of intra-access blood flow with characteristics of stenoses found during diagnostic angiography.

Surveillance of the intra-access blood flow (Qa) has improved identification of thrombosis risk (Qa < or = 500 ml/minute), and these patients are referred for angiogram and angioplasty. The purpose of this study was to correlate the Qa with patient and stenotic lesion characteristics both before and after angioplasty in a retrospective cohort of 210 patients who were preselected on the basis of reduced Qa (369 +/- 121 ml/minute). Angiograms revealed a total of 643 stenoses, and all patients had at least one significant stenosis (>50% luminal narrowing). There was no significant association between the preangioplasty Qa and the number, location, or length of stenoses, but there was a significant negative correlation between the degree of stenosis and the preangioplasty Qa. Five hundred eighty stenoses in 190 patients were treated with angioplasty; the postangioplasty Qa was 633 +/- 208 ml/minute. Of the residual stenoses, all had less than 50% narrowing. There was no correlation between the postangioplasty Qa and the length or degree of stenoses, but there was a significant negative correlation between the postangioplasty Qa and the number of stenoses. We conclude that the primary determinant of reduced preangioplasty Qa is the degree of stenosis, when stenoses are over 50%, whereas the primary determinant of reduced postangioplasty Qa is the number of stenosis. For patients with two or more residual stenoses and failure to achieve Qa > 500 p;ml/minute postangioplasty, the alternative procedure is a prompt surgical revision in order to maintain the goal of access patency.

Bladder vs enteric drainage in simultaneous pancreas-kidney transplantation.

BACKGROUND: As a valid therapeutic option for patients with type 1 diabetes mellitus (IDDM) and secondary diabetic nephropathy, simultaneous pancreas-kidney (SPK) transplantation remains more undeveloped than other solid organ transplantations due to restrictions of surgical techniques, especially modes of exocrine pancreatic secretion. Enteric drainage (ED) has recently been increasingly popular due to the long-term complications with bladder drainage (BD). Objectives. Compare results of SPK transplants with enteric vs bladder exocrine drainage since the beginning of our experience with this type of transplantation. METHODS: From March 1998 to October 2004, 53 SPK transplants were performed, consisting of 30 with bladder drainage (BD) and 23 with enteric drainage (ED). Induction therapy included antilymphocyte globulin (ALG) or anti-CD25 monoclonal antibody. Maintenance regimen consisted of tacrolimus (TAC)/cyclosporine (CsA), mycophenolate mofetil (MMF) and steroids. RESULTS: Mean age of recipients was 39+/-7 in both groups. No anastomosis leakage occurred in either group. Surgical complications were not significantly different between the two groups. Incidence of acute rejection, major infections and cytomegalovirus disease were also similar. However, the BD group was characterized by a slight increase in number of urologic complications, metabolic acidosis and dehydration. The length of initial hospital stay was likewise comparable. All patients with a functional graft no longer required exogenous insulin. BD actuarial patient survival and graft three-year survival were 96 and 86%, respectively. For ED, the respective results were 97 and 91%, respectively. CONCLUSION: Compared with BD, perioperative morbidity is not increased by ED, and ED is not associated with increased long-term pancreas graft failure. These data suggest that ED is superior to BD and should be considered as the preferred technique for simultaneous pancreas-kidney transplants.