SEARCH

SEARCH BY CITATION

Keywords:

  • Complications;
  • kidney graft function;
  • kidney transplantation;
  • laparoscopic nephrectomy;
  • live donor;
  • rejection

Abstract

  1. Top of page
  2. Abstract
  3. Introduction
  4. Patients and Methods
  5. Results
  6. Discussion
  7. Acknowledgments
  8. References

The impact of laparoscopic (lap) live donor nephrectomy on early graft function and survival remains controversial.

We compared 2734 kidney transplants (tx) from lap donors and 2576 tx from open donors reported to the U.S. United Network for Organ Sharing from 11/1999 to 12/2000.

Early function quality (>40 mL urine and/or serum creatinine [creat] decline >25% during the first 24 h post-tx) and delayed function incidence were similar for both groups. Significantly more lap (vs. open) txs, however, had discharge creats greater than 1.4 mg/dL (49.2% vs. 44.9%, p = 0.002) and 2.0 mg/dL (21.8% vs. 19.5%, p = 0.04). But all later creats, early and late rejection, as well as graft survival at 1 year (94.4%, lap tx vs. 94.1%, open tx) were similar for lap and open recipients.

Our data suggests that lap nephrectomy is associated with slower early graft function. Rejection rates and short-term graft survival, however, were similar for lap and open graft recipients. Further prospective studies with longer follow up are necessary to assess the potential impact of the laparoscopic procurement mode on early graft function and long-term outcome.


Introduction

  1. Top of page
  2. Abstract
  3. Introduction
  4. Patients and Methods
  5. Results
  6. Discussion
  7. Acknowledgments
  8. References

Since its first description in 1995 (1), laparoscopic live donor nephrectomy has replaced open nephrectomy over a relatively short time span at many transplant centers. Multiple studies have shown that laparoscopic nephrectomy is considerably gentler for the donor, because it is associated with less postoperative pain, a shorter length of hospital stay, improved cosmesis, and faster return to work and activities of daily living (2). Some investigators have even suggested that the availability of the minimally invasive procurement mode has significantly contributed to the recent increase of live kidney donations in the United States (3–5).

Laparoscopic nephrectomy has thus undeniable benefits for the donor; however, the implications of this new surgical technique for the recipient have been controversial for at least two reasons. First, initial reports suggested higher vascular (6) and ureteral (7) complication rates with laparoscopically procured kidney grafts. But subsequent studies have demonstrated that with increasing surgical experience, low technical complication rates can also be achieved with laparoscopic kidneys, regardless whether left or right kidneys (8), or kidneys with anatomical variations, such as multiple renal arteries, are used (9).

Second, several investigators have shown slower early post-transplant function for laparoscopic (vs. open) grafts, as measured by delayed function rates (10–12) and by the recipients' early post-transplant serum creatinine levels (10,13,14). These findings are a priori not surprising, because warm ischemia times in laparoscopic donors are longer (11), and the pneumoperitoneum created during the laparoscopic operation negatively affects renal hemodynamics (15–18). Slower early function in laparoscopic grafts, however, was not observed on all post-transplant days, did not persist beyond the first month, and did not achieve statistical significance at all time points in all studies (10,11,13,14,19,20). Also, other reports have suggested equivalent early graft function after laparoscopic and open kidney procurement (21,22). Thus, the controversy surrounding the quality of early function of laparoscopic kidney grafts remains unresolved. Nevertheless, analysis of early graft function quality is so important, because previous studies have demonstrated that even mild to moderate early dysfunction can have a negative effect on long-term graft survival (23).

The lack of definitive evidence and the conflicting results of single center studies on early function of laparoscopic kidneys prompted us to compare functional and immunologic outcomes, as well as survival, of laparoscopic and open kidney grafts reported to the U.S. United Network for Organ Sharing (UNOS) kidney registry.

Patients and Methods

  1. Top of page
  2. Abstract
  3. Introduction
  4. Patients and Methods
  5. Results
  6. Discussion
  7. Acknowledgments
  8. References

We reviewed the UNOS database for all live donor kidney transplants carried out in the U.S. from November 1, 1999, to December 31, 2000. For the purpose of this analysis, we defined as ‘open’ kidneys only those that had been removed via a flank approach.

Graft function analysis

We assessed early graft function as follows: >40 mL of urine production during the first 24 h (yes vs. no), serum creatinine level decline by greater than 25% on two separate serum samples taken within the first 24 h (yes vs. no), delayed function (defined as need for dialysis within the first week post-transplant [yes vs. no]), and serum creatinine level [mg/dL] at the time of discharge. We also compared serum creatinine levels at 6 months and 1 year post-transplant.

Immunologic outcome analysis

Acute rejection as reported to the UNOS was analyzed at three different time points: before discharge, within the first 6 months, and within the first year post-transplant.

Graft survival analysis

We calculated graft survival according to Kaplan-Meier. Graft failure was defined as permanent return to dialysis or death with a functioning graft.

Statistical analysis

Donor and recipient demographic and outcome variables were compared between the laparoscopic and open (flank approach) donor groups for all recipients. In a subanalysis, we studied graft function and immunologic outcome for first-graft recipients only. Categorical variables were analyzed using the Chi-square test. The means of continuous variables were analyzed using t-tests. Graft survival rates were calculated using the Kaplan-Meier method employing the log-rank test to detect differences in the survival curves. For all statistical tests, a p-value of less than 0.05 was considered statistically significant.

Results

  1. Top of page
  2. Abstract
  3. Introduction
  4. Patients and Methods
  5. Results
  6. Discussion
  7. Acknowledgments
  8. References

Nephrectomy technique

From November 1, 1999, to December 31, 2000, 6073 live donor kidney transplants were reported to the UNOS. Of the 6073 kidney procurements from live donors, 2734 (45.0%) were carried out with a laparoscopic approach, 2576 (42.4%) with an open, retroperitoneal flank approach, and 377 (6.2%) with an open transabdominal approach. In 386 (6.4%) cases, the procurement technique had not been reported. For the purpose of this study, only the 2734 laparoscopic and the 2576 open procurements that had been carried out through a flank approach were considered.

During the study period, the number of UNOS-accredited kidney transplant programs reporting laparoscopic nephrectomies increased from 58 (30% of all kidney programs) to 80 (41% of all kidney programs). Similarly, the proportion of laparoscopic kidney grafts increased from 34.9% in 11/1999 to 53.5% in 12/2000, while the proportion of open kidney grafts diminished from 51.1% to 35.0%, respectively.

Live donor demographics

Gender distribution and mean age were not significantly different for open vs. laparoscopic donors. Laparoscopic donors had a minimally, but significantly lower weight than open donors (76.0 vs. 77.1 kg, p = 0.038) (Table 1).

Table 1.  Live donor demographics according to the procurement technique1
 Open (n = 2576)Laparoscopic (n = 2734)p-value
  1. 1Total number of patients for individual variables may be less than 2576 (open group) and 2734 (laparoscopic group) as a result of incomplete reporting.

Male/female (%)42.7/57.343.6/56.40.557
Mean age (year)39.239.30.557
Mean weight (kg)77.176.00.038
Ethnicity (n)  0.015
 Caucasian1.795 (69.7%)1.945 (71.1%) 
 African-American317 (12.3%)359 (13.1%) 
 Hispanic336 (13.0%)283 (10.4%) 
 Asian66 (2.6%)83 (3.0%) 
Relationship to 0.20
 recipient (n)
Related1.912 (86.6%)2.001 (85.2%) 
Unrelated297 (13.4%)347 (14.8%) 

Recipient demographics

Recipient demographics are listed in Table 2. Laparoscopic compared with open kidney recipients were significantly older (mean 42.7 year vs. 40.9 year, p < 0.001), more frequently Caucasian and African-American, and less frequently Hispanic (Table 2). We observed significantly more preemptive transplants and retransplants in laparoscopic kidney recipients (Table 2). There was no significant weight difference between the recipients in both groups. Cold ischemia time was similar in both groups (Table 2). We were not able to analyze warm ischemia time because this data point was inconsistently reported (i.e., centers reported variably the warm ischemia time in the donor, the warm ischemia time in the recipient, or the combined [donor plus recipient] warm ischemia time).

Table 2.  Recipient demographics according to the procurement technique1
 Open (n = 2576)Laparoscopic (n = 2734)p-value
  1. 1Total number of patients for individual variables may be less than 2576 (open group) and 2734 (laparoscopic group) as a result of incomplete reporting.

Male/female (%)57.9/42.157.9/42.10.50
Mean age (year)40.942.7<0.001
Mean weight (kg)75.374.30.092
Pretransplant1.877 (74.4%)1.922 (72.7%)0.001
 dialysis (n)
Ethnicity (n)  <0.004
 Caucasian1.782 (70.8%)1.920 (71.8%) 
 African-American326 (13.0%)389 (14.6%) 
 Hispanic333 (13.2%)274 (10.2%) 
 Asian75 (3.0%)91 (3.4%) 
Primary renal  <0.919
 disease (n)
 Glomerulonephritis699 (42.2%)783 (42.4%) 
 Diabetes507 (30.6%)554 (30.0%) 
 Hypertension257 (15.5%)280 (15.1%) 
Polycystic kidney193 (11.7%)228 (12.5%) 
 disease
Retransplant (n)208 (8.1%)244 (8.9%)<0.001
Mean cold2.22.20.913
 ischemia time (h)

Recipient outcomes and graft function

The postoperative length of stay was shorter for recipients of laparoscopic vs. open kidneys: 6.7 days vs. 7.1 days. This low absolute difference of 0.4 days was statistically significant (p = 0.003) (Table 3). Early post-transplant urine production, the serum creatinine decrease during the first 24 h post-transplant, and the incidence of delayed graft function were not significantly different for recipients of laparoscopic vs. open kidney grafts (Table 3). We observed similar results when limiting the analysis to first-graft recipients. However, significantly more laparoscopic kidney recipients had discharge creatinine levels greater than 1.4 mg/dL (p = 0.002) and greater than 2.0 mg/dL (p = 0.04) (Table 3). Recipients of first laparoscopic (vs. open) kidney grafts had also significantly more frequently discharge creatinine levels greater than 1.4 mg/dL (50.1% vs. 45.5%,p = 0.001). We noted no significant differences for open vs. laparoscopic kidneys of the mean serum creatinine levels at 6 months (1.46 mg/dL vs. 1.47 mg/dL) and at 1 year (1.47 mg/dL vs. 1.49 mg/dL). Analysis of serum creatinine levels at 6 months and 1 year for first-graft recipients showed no significant differences between both groups either.

Table 3.  Recipient outcomes according to the procurement technique1
 Open (n = 2576)Laparoscopic (n = 2734)p-value
  1. 1Total number of patients for individual variables may be less than 2576 (open group) and 2734 (laparoscopic group) as a result of incomplete reporting.

Recipient length of stay7.16.70.003
Mean postoperative length of stay (days)7.16.70.003
Early graft function2.420 (94.7%)2.553 (95.2%)0.43
>40 mL urine during first 24 h (n)2.420 (94.7%)2.553 (95.2%)0.43
>25% decrease in creatinine during first 24 h (n)2.215 (86.7%)2.311 (86.2%)0.58
Delayed graft function (n)128 (5.0%)157 (5.9%)0.18
Recipient serum creatinine level at hospital discharge1.873 (75.4%)2.008 (77.6%)0.06
Discharge creatinine >1.0 mg/dL (n)1.873 (75.4%)2.008 (77.6%)0.06
Discharge creatinine >1.4 mg/dL (n)1.116 (44.9%)1.274 (49.2%)0.002
Discharge creatinine >2.0 mg/dL (n)483 (19.5%)564 (21.8%)0.04
Acute rejection incidence133 (5.2%)118 (4.4%)0.17
Rejection during transplant hospital admission (n)133 (5.2%)118 (4.4%)0.17
Rejection within 6 months (n)239 (14.1%)271 (15.5%)0.24
Rejection within 1 year (n)276 (17.4%)300 (18.2%)0.54

Acute rejection

We observed no significant differences of the acute rejection incidence at any of the studied time points. Acute rejection incidence was less than 20% at 1 year in both groups (Table 3). Similarly, analysis of rejection incidence in first-graft recipients showed no significant differences when comparing the two procurement modes.

Graft survival

Graft survival at 1 year was similar in both groups: 94.4% for laparoscopic kidneys vs. 94.1% for open kidneys (for first-graft recipients: 94.6% vs. 94.5%, respectively).

Discussion

  1. Top of page
  2. Abstract
  3. Introduction
  4. Patients and Methods
  5. Results
  6. Discussion
  7. Acknowledgments
  8. References

Over the past 7 years, the surgical approach to live kidney donors has dramatically shifted: many centers have now all but abandoned open in favor of laparoscopic nephrectomy (5). Interestingly, this change in practice was not evidence-based, but mostly driven by the donors' needs and expectations (1), and, to a lesser extent, the recipients' attitudes (24). Initial studies on laparoscopic kidney grafts reported higher rates of surgical complications (related to the transplant ureter) (7) and graft failure (from vascular thrombosis) (6). These concerns, however, have been largely alleviated as a consequence of (i) technical modifications that have resulted in safer ureteral dissection and better preservation of vascular length (7–9), and (ii) increased experience with this new operation.

But the impact of laparoscopic procurement on early graft function and, potentially, long-term outcome remains still controversial. At least three investigators reported three- to four-fold higher delayed graft function rates for laparoscopic vs. open kidneys (10–12). In contrast, in several others studies delayed function rates were similar for both groups (7,10,13,20,22,25). Finally, one center reported a trend towards a higher delayed function rate for open kidneys (19).

The available data on the quality of early graft function, as measured by the recipients' post-transplant serum creatinine levels, is even more contradictory. Nogueira et al. observed significantly higher creatinine levels in laparoscopic kidney recipients from day 1 to day 30 (10). Ratner noted similar significant differences on postoperative days 2 and 3 (13). In one of our previous studies, we found significantly higher creatinine levels in pediatric laparoscopic kidney recipients on day 1 and day 4 (14). Moreover, several additional studies have documented a trend towards higher early post-transplant creatinine levels for laparoscopic graft recipients, albeit not at a statistically significant level (11,19,20). In contrast, other investigators have reported similar early function for laparoscopic and open kidney grafts (21,22). But in all of the above studies, serum creatinine levels were, even when significantly different early post-transplant, similar at all later time points for both groups. Thus, the data on the quality of early graft function after laparoscopic vs. open kidney procurement remains conflicting, controversial, and inconclusive.

To address this controversy, we reviewed the UNOS database for functional and immunologic outcomes of laparoscopically and openly procured kidneys. Both groups were comparable with respect to most donor and recipient demographic variables. The ratio of related to unrelated donors, which may affect immunologic outcome, was similar in both groups. We noted, however, a slightly higher retransplant incidence for laparoscopic kidney recipients. It was previously shown that retransplant recipients have poorer early function than first-graft recipients (26). To account for the higher retransplant rate in the laparoscopic group, we performed a subanalysis of functional and immunologic outcomes that was limited to first-graft recipients. Importantly, demographic donor variables such as gender, age, and weight that may reflect functional nephron mass, and may therefore impact on functional outcome, were not significantly different in both groups. Recipients did not significantly differ with respect to gender and weight either: the ‘functional match’ between donors and recipients was thus comparable in both groups. Recipient age, however, was significantly higher in the laparoscopic group (difference of means, 1.8 year). Also, the postoperative length of stay was statistically significantly shorter (by 0.4 days) for laparoscopic kidney recipients. Clinically, those small absolute differences are likely irrelevant. Nonetheless, the demographic inhomogeneities must be taken into account when analyzing creatinine levels and rejection incidence at hospital discharge. To further increase the meaningfulness of our analysis, we included only open kidneys that had been procured by an extraperitoneal flank approach. If we had included the few kidneys that were procured transabdominally, we may have introduced a bias because the more invasive transabdominal approach may be associated with more operative stress and fluid requirements: both of which could affect kidney perfusion during procurement, and subsequently quality of early graft function after transplantation.

In our analysis, we observed significantly slower early post-transplant graft function in primary and retransplanted laparoscopic donor kidney graft recipients. These findings are consistent with the previously discussed single center studies that had reported higher early post-transplant serum creatinine levels in laparoscopic kidney graft recipients (10,13,14). Our findings are in line with, and explained by, experimental observations that pneumoperitoneum decreases cortical renal blood flow, renal vein flow and creatinine clearance, and causes oliguria (15–17). Clinically, decreased intraoperative urine output during prolonged pneumoperitoneum associated with laparoscopic gastric bypass has been reported (18). Nevertheless, both experimentally and clinically, no permanent adverse effect of the pneumoperitoneum on function or histology of native kidneys has been described (15–18). But in transplanted kidneys, the warm ischemia time in the donor and recipient, as well as the cold ischemia time, albeit short, may add enough injury to result in decreased renal function after reperfusion in the recipient. Also, renal artery spasm secondary to the laparoscopic perivascular dissection (as hypothesized in an initial study) may potentially contribute to higher early post-transplant creatinine levels in laparoscopic graft recipients (9). With increasing surgical experience and adequate intravenous hydration, however, it is unlikely that renal artery spasm was a significant factor affecting post-transplant and laparoscopic graft function.

There is, however, one caveat concerning the interpretation of our data. Laparoscopic recipients were slightly older than open recipients. Given the study design, our analysis would not have been able to account for potential differences in early function caused, for example, by an uneven distribution of cardiovascular comorbidities (i.e., worse cardiac function, less optimal kidney graft perfusion, and poorer early function in the older laparoscopic recipients). Also, laparoscopic recipients were discharged on average 0.4 days earlier home post-transplant than open recipients. This shorter hospital stay may potentially have affected the observed discharge serum creatinine level. But given the small absolute differences, we believe that the slightly higher age and earlier discharge in the laparoscopic group were not major confounding factors. Finally, a higher proportion of laparoscopic kidney recipients was transplanted preemptively, i.e., their residual renal function at the time of transplant was presumably better than in open recipients. Also, kidney transplants from live donors have better long-term outcome if they are carried out preemptively, rather than after initiation of dialysis (27). If this demographic difference had a significant impact on the outcome of our analysis, the discharge serum creatinine level and 1-year graft survival in the laparoscopic group would have overestimated actual early graft function quality and graft survival rate, respectively.

Why is analysis of early graft function so important? It was previously shown that patients with very poor (i.e. delayed) early graft function have a higher incidence of rejection, and that those experiencing both rejection and delayed function have a particularly dismal long-term graft outcome (28). These findings were corroborated in a more recent study that showed that even a milder degree of early graft dysfunction, without the requirement for hemodialysis, can adversely affect long-term outcome (23). The pathophysiology underlying the observation that nonspecific injury leads to immune injury and vice-versa was elegantly summarized in the injury-inflammation-immune recognition triangle hypothesis by Halloran et al. (29). Thus, even a modest degree of nonspecific injury may portend poorer long-term graft survival (23). Any modification of the procurement or transplant procedure that may increase graft injury must therefore be closely scrutinized to rule out adverse long-term consequences.

But to date, no study has shown a significant difference in rejection rate and long-term survival when comparing laparoscopic to open kidney grafts (2,7,10–14,19–22). In our analysis, the procurement mode did not affect acute rejection incidence and long-term graft survival either. There are several possible explanations why the observed differences in early function had no impact on long-term outcome, both in our and other studies. First, the absolute amount of graft injury inflicted by the laparoscopic procurement may have been relatively minor: significant enough to cause higher early post-transplant serum creatinine levels, yet too small to result in any long-term detriment. Further analysis of this question requires study of rejection incidence and long-term outcome in a larger number of patients, comparing in particular recipient outcomes according to early serum creatinine levels (high vs. low).

Second, in the living donor transplant setting, the immunologic and nonimmunologic context may be so favorable that even small differences early in graft injury may have no bearing on long-term outcome. For example, live donor transplantation involves a high proportion of genetically related donors and recipients. Also, live donor kidneys have a better absolute quality than cadaver donor kidneys: they do not suffer traumatic shock and peri-brain death hemodynamic instability, their preservation time is short, the donors are of excellent health, and a relatively low proportion of them is over 50 years of age.

Third, the currently available, highly effective immunosuppression may overcome any potential adverse immunologic consequences that may result from the laparoscopic procurement.

Fourth, as this is a registry analysis, there may be a center effect bias: laparoscopic centers may have a higher transplant volume, be more aggressive and more experienced, and may therefore have better results than centers that still proceed with open procurement. As a result, long-term graft survival may be seemingly similar in both groups. An analysis for a possible center effect, however, would be difficult, as mere program size may not be a good indicator for center quality. Also, the practice is currently shifting so rapidly at many centers, as shown by the change of surgical practice even during our relatively short study time period, that characterization of centers as ‘laparoscopic’ or ‘open’ may be arbitrary.

Fifth, our fairly short follow-up time may be insufficient to detect any relatively small differences in long-term outcome. Clearly, further analysis with longer post-transplant observation and more patients is necessary.

Sixth, there may be a selection bias leading to poorer outcomes for open kidney grafts. For example, kidneys with anatomical variants may still be preferentially procured by open nephrectomy. Implantation of kidneys with multiple arteries, for example, may prolong warm ischemia time during the recipient operation and adversely affect early renal function. At least with regard to demographic variables, however, we were not able to detect any evidence for such bias. Given our study design, a retrospective database review, we were not able to assess for group differences in technical difficulty of the kidney procurement and implantation.

Importantly, our retrospective study has several limitations. A prospective analysis would have allowed us to control for several of the previously discussed, potentially confounding factors. Also, we disposed only of relatively few early data points (i.e. serum creatinine levels), because our analysis was limited by the type of data that is reported to the UNOS. For similar reasons, we were not able to control for the intensity of the immunosuppressive protocols that are used by the different transplant centers. Particularly, differences in early calcineurin inhibitor dosing may have affected both short-term renal function (e.g., serum creatinine levels) and immunologic long-term outcome (e.g., graft loss from rejection). In addition, as discussed earlier, laparoscopic programs may be more experienced, and may have better long-term graft survival by virtue of their field strength. Also, we were not able to assess for differences in intraoperative donor management. The potential importance of this variable was emphasized by experimental and clinical findings suggesting that aggressive intraoperative volume substitution during donor nephrectomy has a positive impact on renal hemodynamics and intrarenal metabolism of vasoactive substances (15,30). Finally, we were not able to control for the potential impact of different laparoscopic procurement techniques. A previously published report suggests that hand-assisted laparoscopic nephrectomy is associated with a shorter warm ischemia time than traditional laparoscopic nephrectomy, mainly because kidney extraction is faster (31). Moreover, hand-assisted nephrectomy was also found to result in shorter operating times (31). This technique may therefore reduce the overall intraoperative hemodynamic stress on the donor kidney. As a result, early function may be better for kidneys that are procured by hand-assisted (vs. traditional) laparoscopic nephrectomy. But the registry data did not allow us to assess and control for the potential impact of a particular laparoscopic procurement technique.

In conclusion, laparoscopic nephrectomy has rapidly gained widespread acceptance, with the majority of live donor kidneys now being procured by this approach. The results of our study, however, suggest that the less invasive technique may be associated with slower early graft function. Nevertheless, this finding did not appear to affect rejection rates and short-term graft survival. Further prospective studies are needed to assess the potential impact of the laparoscopic procurement mode on early graft function. Corroboration of our observations by these studies would provide added rationale for strict adherence to management principles that have been shown to be renoprotective in previous studies, including aggressive intravascular volume expansion (15) and the use of agents that potentially enhance renal perfusion (30,32) during donor nephrectomy, as well as the targeting of specific intraoperative hemodynamic goals during kidney implantation in the recipient (33). Also, if laparoscopic nephrectomy were definitively shown to exert an adverse impact on early graft function, additional studies with longer follow-up times would need to investigate the potential long-term consequences of this new procurement mode with regard to rejection and long-term graft survival.

Acknowledgments

  1. Top of page
  2. Abstract
  3. Introduction
  4. Patients and Methods
  5. Results
  6. Discussion
  7. Acknowledgments
  8. References

The authors thank Dr Mary Ellison and the United Network for Organ Sharing Department of Research for their assistance with the data set and Deborah Hoang for preparation of the manuscript.

The data contained in this manuscript was presented in part at the American Transplant Congress 2002 in Washington, D.C., April 26 – May 1, 2002.

References

  1. Top of page
  2. Abstract
  3. Introduction
  4. Patients and Methods
  5. Results
  6. Discussion
  7. Acknowledgments
  8. References
  • 1
    Ratner LE, Ciseck LJ, Moore RG, Cigarroa FG, Kaufman HS, Kavoussi LR. Laparoscopic live donor nephrectomy. Transplantation 1995; 60: 10471049.
  • 2
    Merlin TL, Scott DF, Rao MM et al.. The safety and efficacy of laparoscopic live donor nephrectomy: a systematic review. Transplantation 2000; 70: 16591666.
  • 3
    Schweitzer EJ, Wilson J, Jacobs S et al.. Increased rates of donation with laparoscopic donor nephrectomy. Ann Surg 2000; 232: 392400.
  • 4
    Kuo PC, Johnson LB. Laparoscopic donor nephrectomy increases the supply of living donor kidneys: a center-specific microeconomic analysis. Transplantation 2000; 69: 22112213.
  • 5
    Cho YW, Bunnapradist S, Peng A, Cecka JM, Danovitch GM. Laparoscopic donor nephrectomy is responsible for the national increase in living donor kidney donation. Am J Transplant 2002; 2 (Suppl 3): 285.
  • 6
    Ratner LE, Kavoussi LR, Chavin KD, Montgomery R. Laparoscopic live donor nephrectomy: Technical considerations and allograft vascular length. Transplantation 1998; 65: 16571658.
  • 7
    Philosophe B, Kuo PC, Schweitzer EJ et al.. Laparoscopic versus open donor nephrectomy: Comparing ureteral complications in the recipients and improving the laparoscopic technique. Transplantation 1999; 68: 497502.
  • 8
    Buell JF, Edye M, Johnson M et al.. Are concerns over right laparoscopic donor nephrectomy unwarranted? Ann Surg 2001; 233: 645651.
  • 9
    Troppmann C, Wiesmann K, McVicar JP, Wolfe BM, Perez RV. Increased transplantation of kidneys with multiple renal arteries in the laparoscopic live donor nephrectomy era. Arch Surg 2001; 136: 897907.
  • 10
    Nogueira JM, Cangro CB, Fink JC et al.. A comparison of recipient renal outcomes with laparoscopic versus open live donor nephrectomy. Transplantation 1999; 67: 722728.
  • 11
    Odland MD, Ney AL, Jacobs DM et al.. Initial experience with laparoscopic live donor nephrectomy. Surgery 1999; 126: 603607.
  • 12
    Wolf JS Jr, Marcovich R, Merion RM, Konnak JW. Prospective, case matched comparison of hand assisted laparoscopic and open surgical live donor nephrectomy. J Urol 2000; 163: 16501653.
  • 13
    Ratner LE, Montgomery RA, Maley WR et al.. Laparoscopic live donor nephrectomy. Transplantation 2000; 69: 23192323.
  • 14
    Troppmann C, Pierce JL, Wiesmann KM et al.. Early and late recipient graft function and donor outcome after laparoscopic vs open adult live donor nephrectomy for pediatric renal transplantation. Arch Surg 2002; 137: 908916.
  • 15
    London ET, Ho HS, Neuhaus AMC, Wolfe BM, Rudich SM, Perez RV. Effect of intravascular Volume expansion on renal function during prolonged CO2 pneumoperitoneum. Ann Surg 2000; 231: 195201.
  • 16
    McDougall EM, Monk TG, Wolf JS Jr. The effect of prolonged pneumoperitoneum on renal function in an animal model. J Am Coll Surg 1996; 182: 317328.
  • 17
    Chiu AW, Chang LS, Birkett DH, Babayan RK. The impact of pneumoperitoneum, pneumoretroperitoneum, and gasless laparoscopy on the systemic and renal hemodynamics. J Am Coll Surg 1995; 181: 397406.
  • 18
    Nguyen NT, Perez RV, Fleming N, Rivers R, Wolfe BM. Effect of prolonged pneumoperitoneum on intraoperative urine output during laparoscopic gastric bypass. J Am Coll Surg 2002; 195: 476483.
  • 19
    London E, Rudich S, McVicar J, Wolfe B, Perez R. Equivalent renal allograft function with laparoscopic versus open live donor nephrectomies. Transplant Proc 1999; 31: 258260.
  • 20
    Stifelman MD, Hull D, Sosa RE et al.. Hand assisted laparoscopic donor nephrectomy: a comparison with the open approach. J Urol 2001; 166: 444448.
  • 21
    Buell JF, Hanaway MJ, Potter SR et al.. Hand-assisted laparoscopic living-donor nephrectomy as an alternative to traditional laparoscopic living-donor nephrectomy. Am J Transplant 2002; 2: 983988.
  • 22
    Sasaki TM, Finelli F, Bugarin E et al.. Is laparoscopic donor nephrectomy the new criterion standard? Arch Surg 2000; 135: 943947.
  • 23
    Humar A, Ramcharan T, Kandaswamy R, Gillingham K, Payne WD, Matas AJ. Risk factors for slow graft function after kidney transplants: a multivariate analysis. Clin Transplant 2002; 16: 425429.
  • 24
    Bartlett ST. Laparoscopic donor nephrectomy after seven years. Am J Transplant 2002; 2: 896897.
  • 25
    Leventhal JR, Deeik RK, Joehl RJ et al.. Laparoscopic live donor nephrectomy – Is it safe? Analysis of 80 consecutive cases and comparison with open nephrectomy. Transplantation 2000; 70: 602606.
  • 26
    Cecka JM. The UNOS Renal Transplant Registry. In: CeckaJM, TerasakiPI, eds. Clinical Transplants 2001. Los Angeles : UCLA Immunogenetics Center, 2002: 118.
  • 27
    Mange KC, Joffe MM, Feldman HI. Effect of the use or nonuse of long-term dialysis on the subsequent survival of renal transplants from living donors. N Engl J Med 2001; 344: 726731.
  • 28
    Troppmann C, Gillingham KJ, Benedetti E et al.. Delayed graft function, acute rejection, and outcome after cadaver renal transplantation. Transplantation 1995; 59: 962968.
  • 29
    Halloran PF, Melk A, Barth C. Rethinking chronic allograft nephropathy: The concept of accelerated senescence. J Am Soc Nephrol 1999; 10: 167181.
  • 30
    Wiesmann KM, Gallay BJ, Foster S et al.. Hypertonic saline infusion during laparoscopic donor nephrectomy increases renal prostaglandin production and Cox-1 transcription: Implications for renoprotection. Am J Transplant 2002; 2 (Suppl 3): 415 (abstract #1100).
  • 31
    Ruiz-Deya G, Cheng S, Palmer E, Thomas R, Slakey D. Open donor, laparoscopic donor and hand assisted laparoscopic donor nephrectomy: a comparison of outcomes. J Urol 2001; 166: 12701274.
  • 32
    Stowe NT, Lee TC, Ambrose JA, Robinson AV, Schulak JA. The combination of 1-arginine and vitamin E protects renal function during CO2 pneumoperitoneum. Am J Transplant 2002; 2 (Suppl 3): 456.
  • 33
    Carlier M, Squifflet JP, Pirson Y, Gribomont B, Alexandre GP. Maximal hydration during anesthesia increases pulmonary arterial pressures and improves early function of human renal transplants. Transplantation 1982; 34: 201204.