Renal transplantation in elderly patients older than 70 years of age: results from the Scientific Registry of Transplant Recipients

BACKGROUND: Elderly patients (ages 70 yr and older) are among the fastest-growing group starting renal-replacement therapy in the United States. The outcomes of elderly patients who receive a kidney transplant have not been well studied compared with those of their peers on the waiting list. METHODS: Using the Scientific Registry of Transplant Recipients, we analyzed data from 5667 elderly renal transplant candidates who initially were wait-listed from January 1, 1990 to December 31, 2004. Of these candidates, 2078 received a deceased donor transplant, and 360 received a living donor transplant by 31 December 2005. Time-to-death was studied using Cox regression models with transplant as a time-dependent covariate. Mortality hazard ratios (RRs) of transplant versus waiting list were adjusted for recipient age, sex, race, ethnicity, blood type, panel reactive antibody, year of placement on the waiting list, dialysis modality, comorbidities, donation service area, and time from first dialysis to first placement on the waiting list. RESULTS: Elderly transplant recipients had a 41% lower overall risk of death compared with wait-listed candidates (RR=0.59; P<0.0001). Recipients of nonstandard, that is, expanded criteria donor, kidneys also had a significantly lower mortality risk (RR=0.75; P<0.0001). Elderly patients with diabetes and those with hypertension as a cause of end-stage renal disease also experienced a large benefit. CONCLUSIONS: Transplantation offers a significant reduction in mortality compared with dialysis in the wait-listed elderly population with end-stage renal disease.     

Cardiac function during laparoscopic vs open gastric bypass

BACKGROUND: Hypercarbia and increased intraabdominal pressure during prolonged pneumoperitoneum can adversely affect cardiac function. This study compared the intraoperative hemodynamics of morbidly obese patients during laparoscopic and open gastric bypass (GBP). METHODS: Fifty-one patients with a body mass index (BMI) of 40-60 kg/m2 were randomly allocated to undergo laparoscopic (n = 25) or open (n = 26) GBP. Cardiac output (CO), mean pulmonary artery pressure (MPAP), pulmonary artery wedge pressure (PAWP), central venous pressure (CVP), heart rate (HR), and mean arterial pressure (MAP) were recorded at baseline, intraoperatively at 30-min intervals, and in the recovery room. Systemic vascular resistance (SVR) and stroke volume (SV) were also calculated. RESULTS: The two groups were similar in terms of age, weight, and BMI. Operative time was longer in the laparoscopic than in the open group (p < 0.05). The HR and MAP increased significantly from baseline intraoperatively, but there was no significant difference between the two groups. In the laparoscopic group, CO was unchanged after insufflation, but it increased by 5.3% at 2.5 h compared to baseline and by 43% compared to baseline in the recovery room. In contrast, during open GBP, CO increased significantly by 25% after surgical incision and remained elevated throughout the operation. CO was higher during open GBP than during laparoscopic GBP at 0.5 h and at 1 h after surgical incision (p < 0.05). During laparoscopic GBP, CVP, MPAP, and SVR increased transiently and PAWP remained unchanged. During open GBP, CVP, MPAP, and PAWP decreased transiently and SVR remained unchanged. There was no significant difference in the amount of intraoperative fluid administered during laparoscopic (5.5 +/- 1.6 L) and open (5.6 +/- 1.7 L) GBP. CONCLUSION: Prolonged pneumoperitoneum during laparoscopic gastric bypass does not impair cardiac function and is well tolerated by morbidly obese patients.     

Early and late recipient graft function and donor outcome after laparoscopic vs open adult live donor nephrectomy for pediatric renal transplantation

BACKGROUND: Laparoscopically procured live donor kidney grafts are increasingly transplanted into pediatric recipients. The safety and efficacy of this changed surgical practice are unknown. HYPOTHESIS: Outcomes of laparoscopic vs open donor grafts in recipients 18 years and younger are equivalent. DESIGN AND SETTING: Retrospective review at an academic tertiary care referral center. PATIENTS: Eleven consecutive pediatric recipients of laparoscopically procured kidneys between April 1, 1997, and December 31, 2001, were pair matched for age with 11 recipients of openly procured kidneys between December 1, 1991, and March 31, 1997; the 22 adult donors were also studied. MAIN OUTCOME MEASURES: Recipients: surgical complications, graft function and survival. Donors: perioperative morbidity and length of hospital stay. RESULTS: Twenty (91%) of 22 kidneys were donated by a parent of the recipient. In recipients of laparoscopically procured grafts, we observed significantly lower creatinine clearances and higher creatinine levels on days 1, 4, and 6, but by 1 month, graft function was similar in both groups. No significant differences in surgical complications, delayed function, acute and chronic rejection, and graft survival rates were found. No laparoscopic or open donor required blood transfusion, reoperation, or hospital readmission. One laparoscopic donor (9%) was converted to open nephrectomy. For laparoscopic vs open donors, median operative time was longer (difference, 67 min; P =.08), but median postoperative length of stay was significantly shorter (3 vs 5 days; P =.02). CONCLUSIONS: Laparoscopic live donor nephrectomy has no adverse impact on pediatric recipient outcomes. For donors, the laparoscopic operation is safe and the hospital stay is shortened. These results support the continued use of laparoscopically procured live donor kidneys in pediatric renal transplantation.     

SRTR Center-Specific Reporting Tools: Posttransplant Outcomes

Measuring and monitoring performance—be it waiting list and posttransplant outcomes by a transplant center, or organ donation success by an organ procurement organization and its partnering hospitals—is an important component of ensuring good care for people with end-stage organ failure. Many parties have an interest in examining these outcomes, from patients and their families to payers such as insurance companies or the Centers for Medicare and Medicaid Services; from primary caregivers providing patient counseling to government agencies charged with protecting patients.
The Scientific Registry of Transplant Recipients produces regular, public reports on the performance of transplant centers and organ procurement organizations. This article explains the statistical tools used to prepare these reports, with a focus on graft survival and patient survival rates of transplant centers—especially the methods used to fairly and usefully compare outcomes of centers that serve different populations. The article concludes with a practical application of these statistics—their use in screening transplant center performance to identify centers that may need remedial action by the OPTN/UNOS Membership and Professional Standards Committee.     

Diagnosing appendicitis with CT and ultrasound using prospective patient stratification by body mass index

Purpose: To determine the accuracy of CT and ultrasonography (US) in diagnosing appendicitis in adults stratified to either modality on the basis of body mass index (BMI), a measure of body habitus. Methods: Seventy-two adults with suspected appendicitis and demonstrating atypical clinical features were prospectively stratified to either appendiceal CT or US based on BMI. Patients with BMI < 30 underwent US and with BMI ≥ 30 underwent CT. Outcomes were determined by surgery, the medical record, and clinical follow-up after 3 months. Results: Of the 72 patients enrolled, 30 (24 women and 6 men) underwent CT and 42 (35 women and 7 men) underwent US. The average BMI was 34 ± 4 among patients who had CT and 24 ± 3 among patients who had US. Of the patients who had CT scans, 4 had positive scans for appendicitis and all of these were proven at surgery to have appendicitis. The remaining 26 patients had negative CT scans for appendicitis. Twenty-two of these were subsequently proven either by surgery or clinical follow-up not to have appendicitis, while 4 were lost to follow-up. This corresponds to a sensitivity, specificity, positive predictive value, and negative predictive value of 100 %. Twelve ultrasound examinations were positive for appendicitis. Nine of these patients had appendicitis proven at surgery, 1 had a perforated Meckel's diverticulum, and 2 did not have appendicitis after clinical follow-up. Twenty-seven patients had negative ultrasound exams for appendicitis. However, 6 of these had appendicitis proven at surgery, 17 did not have appendicitis, and 4 were lost to follow-up. Three patients had ultrasound exams that were equivocal for appendicitis; of these, 1 had appendicitis and 2 did not. For US, this corresponds to a sensitivity of 60 %, specificity of 85 %, PPV of 75 %, and NPV of 74 %. Conclusion: This study suggests that CT is an accurate method of evaluating adults with suspected appendicitis who have BMI ≥ 30. Stratifying patients with BMI < 30 to US did not reproduce the results already reported in the literature.     

A Prospective Evaluation of Intracorporeal Laparoscopic Small Bowel Anastomosis during Gastric Bypass

Background: We evaluated the safety and feasibility of performing a laparoscopic intracorporeal end-toside small bowel anastomosis using a stapling technique as part of a Roux-en-Y gastric bypass operation (RYGBP). Methods: 80 consecutive patients who underwent RYGBP with laparoscopic jejunojejunostomy were evaluated. Operative time and intraoperative and postoperative complications directly related to the jejunojejunostomy anastomosis were recorded. Results: All 80 laparoscopic jejunojejunostomy procedures were successfully performed without conversion to laparotomy. Mean operative time was longer for the first 40 laparoscopic RYGBP than for the last 40 RYGBP (32±18 min vs 21±14 min, respectively, p<0.05). Intraoperative complications were staple-line bleeding (2 patients) and narrowing of the anastomosis (1 patient). Postoperative complications were four small bowel obstructions: technical narrowing at jejunojejunostomy site (2 patients), angulation of the afferent limb (1 patient), and food impaction at the jejunojejunostomy anastomosis (1 patient). These four patients underwent successful laparoscopic re-exploration and creation of another jejunojejunostomy proximal to the original anastomosis. There were no small bowel anastomotic leaks. The median time to resuming oral diet was 2 days. Conclusions: Laparoscopic jejunojejunostomy as part of the RYGBP operation is a safe and technically feasible procedure. Postoperative small bowel obstruction is a potential complication, which can be prevented by avoiding technical narrowing of the afferent limb.     

Effect of suture locking and suture caliber on fatigue strength of flexor tendon repairs

The objectives of this cadaveric study were 2-fold: to determine the effect of different locking configurations on the cyclical fatigue strength of flexor tendon repairs and to assess the differences between each repair when a 3-0 or 4-0 suture is used. One hundred twenty flexor digitorum profundus tendons were cut and repaired using nonlocked, simple locked, and cross-stitch locked variations of 2- and 4-strand flexor tendon repairs. Using an incremental cyclical loading protocol we performed 10 trials of each repair with both 3-0 and 4-0 sutures and analyzed the number of Newton-cycles to failure using a 3-way ANOVA. The use of a 3-0 suture led to a 2- to 3-fold increase in fatigue strength in all repairs tested and the fatigue strength of the 4-strand repairs was significantly greater than the 2-strand repairs. All repairs performed with 4-0 suture failed by suture rupture. Of the 3-0 suture repairs, the three 2-strand repairs and the 4-strand cross-stitch locked repair failed by suture rupture. In contrast, 6 of 10 of the 4-strand simple locked and nonlocked repairs failed by suture pullout. There was no significant difference in fatigue strength between the 2 locked and the nonlocked 2-strand repairs using either 3-0 or 4-0 suture. There also was no significant difference in holding capacity or fatigue strength between the simple locked or nonlocked 4-strand repairs. However, the 4-strand cross-stitch locked repair with a 3-0 suture had significantly improved fatigue strength and holding capacity compared with the other repairs tested. Based on the consistently inferior biomechanical performance of 4-0 suture, we recommend that 3-0 suture be considered for 2- or 4-strand tendon repairs when early active motion is planned. The orientation of the transverse and longitudinal components of simple locked repairs did not significantly influence their holding capacity or fatigue strength. The cross-stitch type of locked repair provides better holding capacity and fatigue strength compared with simple locked or nonlocked 4-stranded flexor tendon repairs.     

The impact of simultaneous pancreas-kidney transplantation on long-term patient survival

BACKGROUND: Simultaneous pancreas-kidney transplantation (SPK) ameliorates the progression of microvascular diabetic complications but the procedure is associated with excess initial morbidity and an uncertain effect on patient survival when compared with solitary cadaveric or living donor renal transplantation. We evaluated mortality risks associated with SPK, solitary renal transplantation, and dialysis treatment in a national cohort of type 1 diabetics with end-stage nephropathy. METHODS: A total of 13,467 adult-type 1 diabetics enrolled on the renal and renal-pancreas transplant waiting list between 10/01/88 and 06/30/97 were followed until 06/30/98. Time-dependent mortality risks and life expectancy were calculated according to the treatment received subsequent to wait-list registration: SPK; cadaveric kidney only (CAD); living donor kidney only (LKD) transplantation; and dialysis [wait-listed, maintenance dialysis treatment (WLD)]. RESULTS: Adjusted 10-year patient survival was 67% for SPK vs. 65% for LKD recipients (P=0.19) and 46% for CAD recipients (P<0.001). The excess initial mortality normally associated with renal transplantation and the risk of early infectious death was 2-fold higher in SPK recipients. The time to achieve equal proportion of survivors as the WLD patients was 170, 95, and 72 days for SPK, CAD, and LKD recipients, respectively (P<0.001). However, the adjusted 5-year morality risk (RR) using WLD as the reference and the expected remaining life years were 0.40, 0.45, and 0.75 and 23.4, 20.9, and 12.6 years for SPK, LKD, and CAD, respectively. There was no survival benefit in SPK recipients > or =50 years old (RR=1.38, P=0.81). CONCLUSIONS: Among patients with type 1 DM with end-stage nephropathy, SPK transplantation before the age of 50 years was associated with long-term improvement in survival compared to solitary cadaveric renal transplantation or dialysis.     

Zone II tendon repairs augmented with autogenous dorsal tendon graft: a biomechanical analysis

We investigated the biomechanical properties of a new technique for tendon repair that reinforces a standard suture with an autogenous tendon graft. A dynamic in situ testing apparatus was used to test 40 flexor digitorum profundus tendons harvested from fresh-frozen cadaver hands. The tendons were cut and repaired using 1 of 4 suture techniques: 2-strand modified Kessler, 4-strand modified Kessler, 6-strand modified Savage, and 2-strand modified Kessler augmented with autogenous dorsal tendon graft. The augmented repair uses 1 slip of the flexor digitorum superficialis tendon secured to the dorsal surface of the repair site with a continuous stitch. Ultimate tensile strength, resistance to gap formation, and work of flexion were measured simultaneously on an in situ tensile testing apparatus. No significant difference in tensile strength was found between the augmented repair and the 6-strand Savage repair. The augmented repair and the 6-strand Savage repair showed significantly greater ultimate tensile strength than the 2- and 4-strand repairs. The augmented repair had significantly greater resistance to 2 mm gap formation than the other 3 repairs. We were unable to show a significant difference in work of flexion between the repairs with the numbers tested (n = 10). Our findings suggest that the augmented repair is strong enough to tolerate the projected forces generated during active motion without dehiscence or gap formation at the repair site.     

Effects of 4-aminopyridine on motor evoked potentials in patients with spinal cord injury: a double-blinded, placebo-controlled crossover trial.

4-Aminopyridine (4-AP) is a potassium (K+) channel blocking agent that has been shown to reduce the latency and increase the amplitude of motor evoked potentials (MEPs) elicited with transcranial magnetic stimulation (TMS) in patients with chronic spinal cord injury (SCI). These effects on MEPs are thought to reflect enhanced conduction in long tract axons brought about by overcoming conduction deficits due to focal demyelination and/or by enhancing neuroneuronal transmission at one or more sites of the neuraxis. The present study was designed to obtain further evidence of reduced central motor conduction time (CMCT) and to determine whether MEPs could be recorded from paretic muscles in which they were not normally elicited. MEPs were elicited with TMS being delivered to subjects (n = 25) pre- and post-administration of 4-AP (10 mg capsule) or placebo. The principal finding was that 4-AP lowered the stimulation threshold, increased the amplitude and reduced the latency of MEPs in all muscles tested, including those that were unimpaired, but did not alter measures of the peripheral nervous system (i.e., M-wave, H-reflex, F-wave). These 4-AP-induced changes in MEPs were significantly greater than those seen with placebo (p < 0.05). The primary implication of these results is that a low dose of 4-AP (immediate-release formulation) appears to improve the impaired central motor conduction of some patients with incomplete SCI. This is most likely attributable to overcoming conduction deficits at the site of injury but may also involve an increase in cortical excitability.