European experience of robot-assisted kidney transplantation: minimum of 1-year follow-up

Robotic Living Donor Hysterectomy for Uterus Transplantation: An Update on Donor and Recipient Outcomes

Background/Objectives: Uterus transplantation (UTx) has evolved into a clinical reality for women with absolute uterine infertility. The international experience with UTx has predominantly utilized living donor grafts-and strategies to minimize harm to donors remain paramount. Robotic living donor hysterectomy represents a minimally invasive approach to facilitate rapid donor recovery, improve pelvic visualization and operative access, and maintain UTx recipient outcomes. The aim of this study is to describe donor, recipient, graft, and pregnancy outcomes after adoption of a robotic living donor hysterectomy program. Methods: The Dallas UtErus Transplant Study (DUETS) incorporated a robotic living donor hysterectomy operative protocol, including transvaginal extraction, from April 2019. Prospectively collected data were analyzed, and a case series presented, to describe donor intra- and post-operative outcomes and recipient intra-operative outcomes, graft viability, established pregnancies, and live births. Early cases were compared to later cases to better describe the learning curve associated with the technique. Results: Sixteen robotic living donor hysterectomies were performed with 100% graft viability after implantation demonstrated by myometrial flow and onset of menses. Early experience (eight cases) demonstrated two cases of ureteric injury. Later experience (eight cases) demonstrated a reduction in operative time (11 h 10 min vs. 6 h 38 min), with no ureteric injuries and a reduction in major operative morbidity from 25% to 12.5% (Clavien-Dindo grade ≥3). At the time of reporting, nine successful live births have occurred, with six ongoing pregnancies. Conclusions: Robotic living donor hysterectomy represents a safe approach to minimize donor harm without compromising UTx recipient, graft, and pregnancy-related outcomes. A learning curve is demonstrated with the adoption of the novel technique-with particularly care required to prevent ureteric injuries, and ongoing vigilance and reporting necessary given the small case numbers of robotic living donor hysterectomy reported internationally.

Systematic review and meta-analysis of the incidence of incisional hernia in urological surgery

PURPOSE

To evaluate the incidence of incisional hernia in patients undergoing direct access to the abdominal cavity in urological surgery.

METHODS

We conducted a systematic review in Pubmed, Embase, and Cochrane Central from 1980 to the present according to the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) statement. Eighty-four studies were selected for inclusion in this analysis, and meta-analysis and meta-regression were performed.

RESULTS

The total incidence in the 84 studies was 4.8% (95% CI 3.7% - 6.2%) I2 93.84%. Depending on the type of incision, it was higher in the open medial approach: 7.1% (95% CI 4.3%-11.8%) I2 92.45% and lower in laparoscopic surgery: 1.9% (95% CI 1%-3.4%) I2 71, 85% According to access, it was lower in retroperitoneal: 0.9% (95% CI 0.2%-4.8%) I2 76.96% and off-midline: 4.7% (95% CI 3.5%-6.4%) I2 91.59%. Regarding the location of the hernia, parastomal hernias were more frequent: 15.1% (95% CI 9.6% - 23%) I2 77.39%. Meta-regression shows a significant effect in reducing the proportion of hernias in open lateral, laparoscopic and hand-assisted compared to medial open access.

CONCLUSION

The present review finds the access through the midline and stomas as the ones with the highest incidence of incisional hernia. The use of the lateral approach or minimally invasive techniques is preferable. More prospective studies are warranted to obtain the real incidence of incisional hernias and evaluate the role of better techniques to close the abdomen.

Incisional hernias post renal transplant: a systematic review and meta-analysis

PURPOSE

Incisional hernia (IH) post renal transplant (RT) is relatively uncommon and can be challenging to manage clinically due to the presence of the kidney graft and patient immunosuppression. This systematic review and meta-analysis synthesises the current literature in relation to IH rates, risk factors and outcomes post RT.

METHODS

PubMed, EMBASE, and Cochrane Central Registry of Controlled Trials (CENTRAL) were searched up to July 2023. The most up to date Preferred Reporting Items for Systematic Reviews and Meta Analyses guidelines were followed. Pertinent clinical information was synthesised. A meta-analysis of the pooled proportions of IH rates, the rates of patients requiring surgical repair and the rates of recurrence post RT are reported.

RESULTS

Twenty studies comprising 16,018 patients were included in this analysis. The pooled rate of IH occurrence post RT was 4% (CI 3-5%). The pooled rate of IH repair post RT was 61% (CI 14-100%). The pooled rate of IH recurrence after repair was 16% (CI 9-23%). Risk factors identified for IH development post RT are BMI, immunosuppression, age, smoking, incision type, reoperation, concurrent abdominal wall hernia, lymphocele formation and pulmonary disease.

CONCLUSIONS

IH post RT is uncommon and the majority of IH post RT are repaired surgically on an elective basis.

Successful robotic kidney transplantation for surgeons with no experience in minimally invasive surgery: a single institution experience

BACKGROUND

Robotic kidney transplantation (RKT) is a novel and welcomed innovation yielding good surgical outcomes. However, data on the feasibility and safety of performing RKT by surgeons with a lack of prior minimally invasive surgery (MIS) experience are limited. The authors aimed to evaluate the surgical and functional results of RKT and present the learning curves (LC) of RKT by a single surgeon with no prior experience in MIS.

MATERIALS AND METHODS

This was a retrospective study of all RKT performed between November 2019 and April 2023 at Severance Hospital in Seoul, South Korea. The authors analyzed surgical and functional outcomes, as well as complication rates of RKT in comparison to open kidney transplantation (OKT). The authors evaluated LCs using the cumulative summation method to describe the number of cases associated with the competency of a single surgeon.

RESULTS

A total of 50 patients who underwent RKT and 104 patients who underwent OKT were included in this study. In RKT group, the median surgical console time was 193 min (interquartile range, 172-222) and the median vascular anastomoses time was 38 min (35-44). Total operation time was 323 min (290-371) and rewarming time was 62.5 min (56.0-70.0) in RKT group compared to 210 min (190-239) and 25 min (21-30), respectively, in OKT group. Despite extended surgical durations with a robotic technique, both groups had comparable intraoperative and postoperative outcomes, as well as renal function. Estimated blood loss and post-transplant hospital stays were significantly lower in RKT group than in OKT group. LC analysis of RKT by the single surgeon revealed that surgical competence was achieved after 15 cases.

CONCLUSION

Even if surgeons do not have prior experience with MIS, they can rapidly overcome the LC and safely perform RKT with adequate preparation and acquisition of basic robotic surgical techniques.

Open versus robotic-assisted kidney transplantation: A systematic review by the European Association of Urology (EAU) - Young Academic Urologists (YAU) Kidney Transplant Working Group

INTRODUCTION

In the last 20 years, robotic assisted procedures were evaluated in the field of kidney transplantation to provide a mini-invasive approach for this particularly fragile population. As a relatively new issue, few studies compared open kidney transplantation (OKT) and robotic-assisted kidney transplantation (RAKT), mostly in small cohorts. To improve current knowledge, we wanted here to gather comparative data of OKT vs RAKT in a systematic review.

METHODS

A systematic review was performed according to preferred reporting items for systematic reviews and meta-analyses. Medline, Embase, and Cochrane databases were searched to identify all studies reporting post-operative outcomes of RAKT versus OKT.

RESULTS

A total of 2136 patients in 13 studies were included. Median recipient age was 42.6 years (OKT: 43.5 years and RAKT: 40.3 years). Median preemptive kidney transplantation rate was 27.1 % (OKT: 23.3 % and RAKT: 33.2 %). Median total operative time and rewarming were respectively: 235 and 49 min in OKT population; 250 and 60 min in RAKT population. Post-operative complications rates were: 26.2 % in OKT population and 17.8 % in RAKT population. Delayed graft function rates were: 4.9 % in OKT population and 2.3 in RAKT population. Mid-term functional outcomes, patient and graft survival were similar in OKT and RAKT population.

CONCLUSION

This systematic review showed that RAKT may be associated with a lower incidence of delayed graft function and post-operative surgical complications and similar mid-term functional outcomes, patient and graft survival, compared to OKT for end-stage renal disease patients.

Impact of robotic-assisted kidney transplantation on post-transplant infections: a case-control study

BACKGROUND

The aim of this study was to determine the differences in the incidence, epidemiology, clinical characteristics and risk factors of infections in living donor kidney transplant recipients using robotic-assisted kidney transplantation (RAKT) and open approach.

METHODS

We conducted a retrospective observational study from January 2016 to December 2019. For the risk factor analysis, a matched case-control study (1:1 ratio) was performed (robotic vs open). Control subjects were matched for living donor and time of transplantation. The data included de novo immunosuppressive regimen, delayed graft function, urological complications, acute allograft rejection and incidence, clinical features, microbiological findings and outcomes of infections.

RESULTS

Ninety-four RAKT and 84 controls were included. There were no differences between groups in terms of age, gender, BMI, median days of hospitalization, immunosuppressive regimen, need for surgical urologic procedures post-transplantation, presence of urinary leak or acute allograft rejection. Thirty-five percent of all recipients analyzed presented an infection, mostly asymptomatic bacteriuria (49%), symptomatic urinary tract infection (31%) and surgical site infection (10%). Pseudomonas aeruginosa was the most frequent isolated microorganism in 67%, followed by E. coli (20%), Enterococcus faecalis (17%) and Klebsiella pneumoniae (10%). Eight percent of the microorganisms were multidrug resistant. The open kidney transplantation group presented more infections compared to RAKT (43 vs 27%, p = 0.04). After multivariate analysis, need for surgical urologic procedure post-transplantation (OR 6.2, 95% CI 1.1-35), BMI ≥ 30 (OR 3.6, 95% CI 1.5-9) and acute allograft rejection (OR 3.2, 95% CI 1.2-8.5) were associated with infection, whereas RAKT (OR 0.5, 95% CI 0.2-0.9) and the use of JJ catheter (OR 0.36, 95% CI 0.17-0.72) were protective factors.

CONCLUSIONS

Infection is a frequent event in patients receiving a living donor kidney transplant. Acute allograft rejection, need for surgical urologic procedure post-transplantation and BMI were associated with infection, whereas robotic surgery was a protective factor in living donor kidney transplantation.

The learning curve for open and minimally-invasive kidney transplantation: a systematic review

INTRODUCTION

There is lack of evidence on the impact of surgeons' learning curve on postoperative outcomes after open (OKT) or minimally-invasive (robot-assisted) kidney transplantation (RAKT). The aim of the review was to assess the learning curve (LC) for OKT and RAKT, focusing on intra-, perioperative and functional outcomes.

EVIDENCE ACQUISITION

A systematic review of the English-language literature published between 01/01/2000 - 10/12/2021 was conducted using the MEDLINE (Via PubMed), Web of Science and the Cochrane Library databases according to the principles highlighted by the EAU Guidelines Office and the PRISMA statement recommendations. The review protocol was registered on PROSPERO (CRD42022301132). The overall quality of evidence was assessed according to GRADE recommendations.

EVIDENCE SYNTHESIS

Twelve studies were included in the qualitative analysis. Surgical competence in terms of operative and re-warming times was defined after 30 cases in OKT and after 11-35 cases in RAKT. Decreased complications rates were observed after 20-33 cases in OKT and 10-30 cases in RAKT. Optimal functional outcomes were achieved after 33 cases in OKT and 15-25 cases in RAKT. However, while a poor OKT experience did not influence the LC for RAKT, lack of robotic surgery exposure could lead to a longer LC for the robotic approach.

CONCLUSIONS

OKT and RAKT appear to have similar LCs and might require about 30 cases to achieve optimal surgical and functional outcomes. Previous expertise in OKT is warranted to shorten the LC for RAKT. Further research is needed to validate these thresholds using standardized reporting metrics.

Recommendations for living donor kidney transplantation

This Guide for Living Donor Kidney Transplantation (LDKT) has been prepared with the sponsorship of the Spanish Society of Nephrology (SEN), the Spanish Transplant Society (SET), and the Spanish National Transplant Organization (ONT). It updates evidence to offer the best chronic renal failure treatment when a potential living donor is available. The core aim of this Guide is to supply clinicians who evaluate living donors and transplant recipients with the best decision-making tools, to optimise their outcomes. Moreover, the role of living donors in the current KT context should recover the level of importance it had until recently. To this end the new forms of incompatible HLA and/or ABO donation, as well as the paired donation which is possible in several hospitals with experience in LDKT, offer additional ways to treat renal patients with an incompatible donor. Good results in terms of patient and graft survival have expanded the range of circumstances under which living renal donors are accepted. Older donors are now accepted, as are others with factors that affect the decision, such as a borderline clinical history or alterations, which when evaluated may lead to an additional number of transplantations. This Guide does not forget that LDKT may lead to risk for the donor. Pre-donation evaluation has to centre on the problems which may arise over the short or long-term, and these have to be described to the potential donor so that they are able take them into account. Experience over recent years has led to progress in risk analysis, to protect donors' health. This aspect always has to be taken into account by LDKT programmes when evaluating potential donors. Finally, this Guide has been designed to aid decision-making, with recommendations and suggestions when uncertainties arise in pre-donation studies. Its overarching aim is to ensure that informed consent is based on high quality studies and information supplied to donors and recipients, offering the strongest possible guarantees.

Three-dimensional Augmented Reality-guided Robotic-assisted Kidney Transplantation: Breaking the Limit of Atheromatic Plaques

BACKGROUND

Robotic-assisted kidney transplantation (RAKT) has shown solid results as a minimally invasive alternative to the standard open approach (open kidney transplantation [OKT]). However, RAKT is still limited in those cases where the recipient's iliac vessels present atherosclerotic plaques, frequently found in elder patients and in those subjected to long-term hemodialysis. Unlike OKT, where the surgeon can palpate the arterial plaques, in minimally invasive surgery the haptic feedback is missing, making the vascular clamping and arteriotomy unsafe.

OBJECTIVE

To employ three-dimensional (3D) imaging reconstruction using augmented reality (AR) to intraoperatively locate the plaques during the crucial steps of kidney transplantation.

DESIGN, SETTING, AND PARTICIPANTS

Our study was conducted according to the Idea, Development, Exploration, Assessment, and Long-term follow-up (IDEAL) model for surgical innovation. Three-dimensional virtual models were obtained from high-accuracy computed tomography scan imaging and superimposed on the vessels during RAKT using the Da Vinci console software.

SURGICAL PROCEDURE

Three-dimensional AR-guided robotic-assisted kidney transplantation.

MEASUREMENTS

The correspondence of virtual models with the real anatomy of patients was assessed comparing vessels' and plaques' measures.

RESULTS AND LIMITATIONS

We tested the possibility of using the AR in the setting of vascular surgery by checking the correspondence of the virtual models to the real vessels. During the accuracy assessment, we investigated the anatomy of the iliac plaques and the capacity of the virtual models to correctly represent them. Finally, we tested the efficacy of the virtual model superimposition on the real vessels with plaques during RAKT in the recipients of living donor grafts. The main limitation consists in training needed to correctly superimpose virtual models on the real field.

CONCLUSIONS

The employment of 3D AR allowed surgeons to overcome one of the main limitations of RAKT, setting the foundation to expand its indications to patients with advanced atheromatic vascular disease.

PATIENT SUMMARY

The use of three-dimensional augmented reality guidance during kidney transplantation (KT) has the potential to "navigate" the surgeon during KT, allowing a safer procedure in patients with atheromatic vascular disease.

Robot-assisted kidney transplantation: Is it getting ready for prime time?

Kidney transplantation (KT) is the treatment of choice for patients with end-stage renal disease, providing a better survival rate and quality of life compared to dialysis. Despite the progress in the medical management of KT patients, from a purely surgical standpoint, KT has resisted innovations during the last 50 years. Recently, robot-assisted KT (RAKT) has been proposed as an alternative approach to open surgery, especially due to its potential benefits for fragile and immunocompromised recipients. It was not until 2014 that the role of RAKT has found value thanks to the pioneering Vattikuti Urology Institute-Medanta collaboration that conceptualized and developed a new surgical technique for RAKT following the Idea, Development, Exploration, Assessment, Long-term follow-up recommendations for introducing surgical innovations into real-life practice. During the last years, mirroring the Vattikuti-Medanta technique, several centers developed RAKT program worldwide, providing strong evidence about the safety and the feasibility of this procedure. However, the majority of RAKT are still performed in the living donor setting, as an “eligible” procedure, while only a few centers have realized KT through a robotic approach in the challenging scenario of cadaver donation. In addition, despite the spread of minimally-invasive (predominantly robotic) surgery worldwide, many KTs are still performed in an open fashion. Regardless of the type of incision employed by surgeons, open KT may lead to non-negligible risks of wound complications, especially among obese patients. Particularly, the assessment for KT should consider not only the added surgical technical challenges but also the higher risk of postoperative complications. In this context, robotic surgery could offer several benefits, including providing a better exposure of the surgical field and better instrument maneuverability, as well as the possibility to integrate other technological nuances, such as the use of intraoperative fluorescence vascular imaging with indocyanine green to assess the ureteral vascularization before the uretero-vesical anastomosis. Therefore, our review aims to report the more significant experiences regarding RAKT, focusing on the results and future perspectives.

Comparison of Open and Robot-Assisted Kidney Transplantation in terms of Perioperative and Postoperative Outcomes

Background

The gold standard treatment method for end-stage renal disease (ESRD) is renal transplantation (RT). RT can be done with open or minimally invasive surgical methods. We aimed to compare the outcomes between patients who underwent robot-assisted renal transplantation (RART) and open renal transplantation (ORT).

Methods

Data of the patients who underwent ORT or RART in two institutions between June 2015 and February 2020 were retrospectively reviewed. Patients who underwent live donor RT were included, and all donor nephrectomy procedures were performed by the laparoscopic technique. Demographic data, ischemia times, anastomosis times, operation times, and postoperative complications were recorded.

Results

98 patients were included in the ORT group, while 91 patients were included in the RART group. There was a significant difference between the two groups regarding mean patient age. While total ischemia time was 86.9 ± 7 minutes in the RART group, it was calculated as 71.2 ± 3.3 minutes in the ORT group, with a significant difference. The anastomosis time was significantly shorter in the ORT group than in the RART group. The incision length and duration of hospital stay were significantly shorter, visual analogue scores were significantly lower, and estimated blood loss was less in the RART group than in the ORT group.

Conclusion

Both ORT and RART are effective and safe methods for treating ESRD. According to our study, RART is associated with relatively longer ischemia times but lower complication rates and higher patient comfort.

Robot-assisted kidney transplantation: an update

Renal transplantation has become the gold-standard treatment for the majority of patients with established renal failure. Recent decades have seen significant progress in immunosuppressive therapies and advances in post-transplant management of recipients, resulting in improved graft and patient outcomes. However, the open technique of allograft implantation has stood the test of time, remaining largely unchanged. In a world where major advances in surgery have been facilitated by innovations in the fields of biotechnology and medical instrumentation, minimally invasive options have been introduced for the recipient undergoing kidney transplantation. In this review we present the evolution of minimally invasive kidney transplantation, with a specific focus on robot-assisted kidney transplant and the benefits it offers to specific patient groups. We also discuss the ethical concerns that must be addressed by transplant teams considering developing or referring to robotic programs.

Prospective comparative study of postoperative systemic inflammatory syndrome in robot-assisted vs. open kidney transplantation

PURPOSE

Robot-assisted kidney transplant (RAKT) recently proved to provide functional results similar to the preferred open kidney transplant (OKT), but with inferior wound morbidity. In a comparative prospective study, we explored the systemic inflammatory response syndrome (SIRS) after KT and compared OKT with RAKT.

METHODS

Forty-nine patients underwent pre-emptive ABO-compatible kidney transplantations (KT) between January 2017 and December 2018 in 2 centers: 25 RAKT, 24 OKT. Postoperative SIRS was biologically assessed by serum markers (NGAL, CRP and IL-6) measured at: T0 (preoperative/baseline), T1(H1), T2(H6), T3(H12), T4(H24), T5(D2), T6(D3) and T7(D5) after KT.

RESULTS

Inflammatory markers + eGFR were assessed in OKT vs. RAKT. IL-6 peak value occurred at H6 and reached ×9 from baseline. CRP peak occurred at H24 and reached ×28 from baseline (All P < 0.05). NGAL decreased after surgery with a plateau (divided by 2 from baseline) from H12 to D5. There was no significant difference in IL-6, CRP and NGAL kinetics and peak values between RAKT and OKT (All P > 0.05). Serum creatinine and eGFR on postoperative days 1, 3 and 7 were similar in RAKT and OKT (All P > 0.05). Delayed graft function was not observed.

CONCLUSION

In this exploratory study, the biological evaluation of postoperative SIRS after living-donor kidney transplant revealed no significant difference between OKT and RAKT and similar functional outcomes in the short term. These results highlight the safety of RAKT as an alternative to OKT in this setting.

Intracorporeal Versus Extracorporeal Robot-assisted Kidney Autotransplantation: Experience of the ERUS RAKT Working Group

BACKGROUND

Kidney autotransplantation is a useful technique to be reserved for cases in which kidney function is compromised by a complex anatomical configuration, such as long ureteral strictures and renal vascular anomalies not suitable for in situ reconstruction. Robot-assisted kidney autotransplantation (RAKAT) presents a novel, minimally invasive, and highly accurate approach.

OBJECTIVE

The aim of this study is to present the largest cohort of patients who underwent either extracorporeal (eRAKAT) or intracorporeal (iRAKAT) RAKAT, to confirm safety and feasibility and to compare the two approaches.

DESIGN, SETTING, AND PARTICIPANTS

We retrospectively analyzed prospectively followed patients undergoing eRAKAT and totally intracorporeal RAKAT in a total of three institutions.

SURGICAL PROCEDURE

Extracorporeal RAKAT and iRAKAT.

MEASUREMENTS

Surgical and functional outcomes of patients subjected to eRAKAT and iRAKAT were measured.

RESULTS AND LIMITATIONS

Between January 2017 and February 2021, 29 patients underwent RAKAT: 15 eRAKAT and 14 iRAKAT. No statistical difference in the preoperative data was recorded. The analysis of intraoperative variables showed a statistically significant difference between eRAKAT and iRAKAT in cold ischemia time (median [interquartile range {IQR}]: 151 [125-199] vs 27.5 [20-55]; p <  0.001) and total ischemia time (median [IQR]: 196.2 [182-241] vs 81.5 [73-88]; p <  0.001). However, faster renal function recovery in favor of eRAKAT was observed during the first 90 d, with comparable renal function at 1 yr. The 90-d Clavien-Dindo >2 complications were 13.8%. It is important to stress that RAKAT, and above all iRAKAT, should be performed by surgeons with experience in robotic renal, vascular, and transplant surgery.

CONCLUSIONS

Both eRAKAT and iRAKAT represent promising minimally invasive techniques in selected cases with acceptable ischemia time and comparable long-term operative outcomes.

PATIENT SUMMARY

In selected patients, both extra- and intracorporeal robot-assisted kidney autotransplantation represent valid alternatives in case of long ureteral strictures and renal vascular anomalies not suitable for in situ reconstruction.

Dallas UtErus Transplant Study: Early Outcomes and Complications of Robot-assisted Hysterectomy for Living Uterus Donors

BACKGROUND

Uterus transplantation is a treatment for absolute uterine infertility and can be performed with living and deceased donors. Given the safety and increased utilization of robotic assistance with other gynecologic and transplant donor operations, we adopted a robot-assisted approach to donor hysterectomy. This study compared early outcomes and morbidity of the robot-assisted approach to donor hysterectomy with the traditionally performed open approach and addressed whether the robot-assisted approach is safe and offers advantages for the donor.

METHODS

Our institution has performed 18 living donor hysterectomies for uterus transplantation. This retrospective review compared the last 5 cases utilizing a robot-assisted technique and vaginal extraction of the uterus graft with the first 13 cases performed with an open laparotomy technique. Demographic, intraoperative, and postoperative data were examined.

RESULTS

There were no differences between the robot-assisted and the open living donor group with respect to age, body mass index, or gynecological history. Although the median operative time was shorter for the open approach (6.27 versus 10.46 h), the donors' median estimated blood loss, length of hospital stay, and length of sick leave were less with the robot-assisted approach. There was no conversion to open hysterectomy in the robot-assisted cases, and the incidence of complications was similar between the 2 groups. There was no difference in early graft function.

CONCLUSIONS

These preliminary results show that robot-assisted living donor hysterectomy is feasible and safe for the donors; it allows a faster postoperative recovery and the same early graft function.

Step-by-step Development of a Cold Ischemia Device for Open and Robotic-assisted Renal Transplantation

BACKGROUND

Kidney transplantation (KT) is the best renal replacement treatment. The rewarming time is associated with ischemia/reperfusion damage. In both the open (open KT [OKT]) and the robotic (robotic-assisted KT [RAKT]) approaches, ice slush is used to maintain graft temperature (T°) below 20 °C. This may result in nonhomogeneous graft T° maintenance and, particularly during RAKT where the graft is completely inside the abdominal cavity, rises concerns regarding systemic hypothermia.

OBJECTIVE

To design a cold ischemia device (CID) to maintain a constant and homogeneous low graft T° during surgery.

DESIGN, SETTING, AND PARTICIPANTS

In IDEAL phase 0, a CID was developed and tested to determine its cooling effect on the kidney inside a closed system at 37.5 °C, by comparing it with kidney alone versus a gauze-jacket filled with ice slush. The CID was evaluated in pigs undergoing OKT and RAKT, assessing feasibility and adverse reactions. In IDEAL phase 1, the CID was tested in human OKT and RAKT.

SURGICAL PROCEDURE

OKT and RAKT.

MEASUREMENTS

In all phases, T° was evaluated at scheduled time points.

RESULTS AND LIMITATIONS

In the preliminary tests of IDEAL phase 0, the CID was able to maintain a low graft T° and superiority to other groups (p =  0.002). In the in vivo animal model, the CID maintained a low and constant graft T° in OKT (n = 3) and RAKT (n = 3), with a mean T° at 50 min of 10.8 °C and 14.9 °C, respectively. IDEAL phase 1 demonstrated feasibility of both approaches (OKT, n = 2 and RAKT, n = 3) using the CID, and graft T° never exceeded 20 °C (mean T°: OKT 15.7 °C vs RAKT 18.3 °C). No complications were recorded. The main limitation consists in the low number of participants.

CONCLUSIONS

The CID assured a constant low graft T° during rewarming time, in both OKT and RAKT.

PATIENT SUMMARY

A cold ischemia device (CID) is the first step toward a feasible, safe, and reproducible method to maintain a low graft temperature during surgery. The employment of a CID may optimize the functional outcomes.

Comparative analysis of outcomes and long-term follow-up of robot-assisted pediatric kidney transplantation, with open counterpart

How does the robotic kidney transplant fare against the open technique, in pediatric patients? No one knows. To address this question, this study compares the outcomes of robotic kidney transplants, with those of open transplant in these patients. This study was a retrospective analysis of outcomes (renal function and complications), of all pediatric patients (<18 years of age), who underwent kidney transplant at our institute, after 2014, till their last follow-up. Fisher's exact test was used to compare proportions. Continuous variables were analyzed using Mann-Whitney test. P value of <.05 was considered significant. Of the twenty-five patients included, 21 belonged to open group, and 4 to the robotic group. Patients in the robotic group had significantly higher Re-WIT (P value .002) and had lower analgesia requirement (P value .04). Median follow-up period was 31 months. Both groups were comparable in terms of length of hospital stay, blood transfusion, and renal function post-operatively till their last follow-up. Three patients in the open group had surgical site infection as compared to none in the robotic group. All the patients had functioning grafts till their last follow-up. Robotic transplant is safe and delivers functional results similar to open technique, with lesser pain and better cosmesis. Longer Re-WIT in robotic transplant has no impact on post-operative renal function. Ours is the first known effort to compare robotic technology with the established open technique of transplant in this population. A prospective randomized controlled trial should refine the results of the present study.

Initial Experience with Single-port Robotic-assisted Kidney Transplantation and Autotransplantation

BACKGROUND

Compared with the standard open approach, multiport robotic-assisted kidney transplantation (RAKT) has emerged as a less morbid alternative. The use of a single-port robotic approach for kidney transplantation (KT) is presented in this study as having the potential for further reducing the morbidity of KT.

OBJECTIVE

To present the technique and evaluate perioperative and short-term (≤1 yr) postoperative outcomes of single-port RAKT.

DESIGN, SETTING, AND PARTICIPANTS

Prospective evaluation of peri- and postoperative outcomes in patients who underwent allograft KT (n = 6) or kidney autotransplantation (n = 3). The IDEAL model (www.ideal-collaboration.net/framework) for safe surgical innovation was used.

SURGICAL PROCEDURE

Kidney allografts from living or deceased donors were transplanted into six patients with end-stage renal disease. Single-port robotic surgery was performed through a 5-cm midline periumbilical abdominal incision with transperitoneal or extraperitoneal approaches. With similar incision and technique, the right or left kidney was removed and autotransplantation was performed in three patients.

MEASUREMENTS

Intra- and postoperative variables, and outcomes were assessed with a descriptive analysis.

RESULTS AND LIMITATIONS

Single-port RAKT procedures were completed successfully, with total operative and vascular anastomosis times ranging from 300 to 450 mins and from 52 to 92 mins, respectively. All six patients had excellent graft function with serum creatinine levels at the last follow-up (2 wk to 1 yr), ranging from 1.2 to 1.5 mg/dl. Renal autotransplantation was also completed successfully with a single-port robotic approach in three patients. The total operative and vascular anastomosis times ranged from 510 to 600 mins and from 65 to 83 mins, respectively. In all three cases, serum creatinine levels remained normal after the surgery and during follow-up, and all remained symptom-free at the time of this writing (4-8 mo after their surgeries).

CONCLUSIONS

In this initial experience, single-port RAKT is feasible with potential benefits such as offering true single-site minimally invasive surgery, extraperitoneal approach, less morbidity, and comparable short-term graft functional outcomes.

PATIENT SUMMARY

We presented the initial experience with the application of single-port robotic surgery for kidney transplantation and autotransplantation. This technique was found to be safe and effective, with promising postoperative outcomes and potentially with less morbidity.

Pediatric Challenges in Robot-Assisted Kidney Transplantation

Kidney transplantation is universally recognized as the gold standard treatment in patients with End-stage Kidney Disease (ESKD, or according to the latest nomenclature, CKD stage 5). Robot-assisted kidney transplantation (RAKT) is gradually becoming preferred technique in adults, even if applied in very few centra, with potentially improved clinical outcomes compared with open kidney transplantation. To date, only very few RAKT procedures in children have been described. Kidney transplant recipient patients, being immunocompromised, might be at increased risk for perioperative surgical complications, which creates additional challenges in management. Applying techniques of minimally invasive surgery may contribute to the improvement of clinical outcomes for the pediatric transplant patients population and help mitigate the morbidity of KT. However, many challenges remain ahead. Minimally invasive surgery has been consistently shown to produce improved clinical outcomes as compared to open surgery equivalents. Robot-assisted laparoscopic surgery (RALS) has been able to overcome many restrictions of classical laparoscopy, particularly in complex and demanding surgical procedures. Despite the presence of these improvements, many challenges lie ahead in the surgical and technical–material realms, in addition to anesthetic and economic considerations. RALS in children poses additional challenges to both the surgical and anesthesiology team, due to specific characteristics such as a small abdominal cavity and a reduced circulating blood volume. Cost-effectiveness, esthetic and functional wound outcomes, minimal age and weight to undergo RALS and effect of RAKT on graft function are discussed. Although data on RAKT in children is scarce, it is a safe and feasible procedure and results in excellent graft function. It should only be performed by a RAKT team experienced in both RALS and transplantation surgery, fully supported by a pediatric nephrology and anesthesiology team. Further research is necessary to better determine the value of the robotic approach as compared to the laparoscopic and open approach. Cost-effectiveness will remain an important subject of debate and is in need of further evaluation as well.

[Living-donor robotic-assisted kidney transplantation: French academic center experience]

INTRODUCTION

The main objective was to report the intra-, post-operative and functional outcomes of living-donor robotic-assisted kidney transplantation (RAKT), performed by a surgeon skilled in robotic surgery. The secondary objective was to compare the results of RAKT, based on the surgeon's experience.

METHODS

For this retrospective cohort study, we analyzed data from consecutive patients who underwent living-donor RAKT from July 2015 to March 2020 and compared the results of RAKT according to the surgeon's experience (group 1: 1-14th RAKT versus group 2: 15-29th RAKT).

RESULTS

Twenty-nine living-donor RAKT were performed. The median age and BMI of the recipients were: 57.0 (44.0-66.0) years and 32.7 (23.5-39.6)kg/m². The median overall operative time and median console time were: 140.0 (122.5-165.0) and 120.0 (107.5-137.5) minutes. The median rewarming time, arterial, venous and urinary anastomoses durations were: 35.0 (27.5-45.0), 15.0 (11.0-20.0), 12.0 (10.0-16.0), 20.0 (16.0-23.0) minutes. Two (6.9%) minor and 5 (17.2%) major (Clavien-Dindo≥III) postoperative complications occurred. At 2 years of follow-up, patient and transplant survival was 100% (n=29) and 93.1% (n=27). After the 14th RAKT, the rewarming time (P=0.01) and venous anastomosis duration (P=0.004) were statistically shorter.

CONCLUSION

Living-donor robotic-assisted kidney transplantation, performed by a surgeon skilled robotic surgery, ensures good functional results in the medium term.

LEVEL OF EVIDENCE

3.

Robot-Assisted Laparoscopic Living Donor Nephrectomy: The University of Florence Technique

Objective: To provide a step-by-step overview of the University of Florence technique for robotic living donor nephrectomy (LDN), focusing on its technical nuances and perioperative outcomes.

Methods: A dedicated robotic LDN program at our Institution was codified in 2012. Data from patients undergoing robotic LDN from 2012 to 2019 were prospectively collected. All robotic LDNs were performed by a highly experienced surgeon, using the da Vinci Si robotic platform in a three-arm configuration. In this report we provide a detailed overview of our surgical technique for robotic LDN. The main objective of the study was to evaluate the technical feasibility and safety of the technique, including perioperative surgical complications rate and mid-term functional outcomes.

Results: Overall, 36 patients undergoing robotic LDNs were included in the study. Of these, 28 (78%) were left LDNs. Median (IQR) donor pre-operative eGFR was 88 (75.6–90) ml/min/1.73 m². In all cases, robotic LDN was completed without need of conversion. The median (IQR) overall operative time was 230 (195–258) min, while the median console time was 133 (IQR 117-166) min. The median (IQR) warm ischemia time was 175 (140–255) s. No intraoperative adverse events or 90-d major surgical complications were recorded. At a median (IQR) follow-up of 24 months (IQR 11-46), median (IQR) eGFR patients undergoing in living donor nephrectomy was 57.4 (47.9; 63.9) ml/min/1.73 m².

Conclusions: In our experience, robotic LDN is technically feasible and safe. The use of robotic surgery for LDN may provide distinct advantages for surgeons while ensuring optimal donors' perioperative and functional outcomes.

Robot-Assisted versus Conventional Open Kidney Transplantation: A Meta-Analysis

Background

Perioperative and follow-up outcomes for patients that received robot-assisted kidney transplant (RAKT), compared to patients that received conventional open kidney transplant (OKT), remain unknown. We performed a meta-analysis of controlled studies to compare the safety and efficacy of RAKT versus OKT.

Methods

Systematic searching of PubMed, Embase, and Cochrane Library databases was performed to identify relevant randomized or nonrandomized controlled studies. Perioperative, in-hospital, and follow-up outcomes were summarized. A random-effect model incorporating the potential heterogeneity was used to synthesize the results.

Results

Six nonrandomized controlled studies including 263 patients with RAKT and 804 patients with OKT were included. Pooled results showed that compared to those that received OKT, patients that received RAKT had significant higher rewarming time (mean difference (MD): 20.8 min, p < 0.001) and total ischemia time (MD: 17.8 min, p = 0.008) but a lower incidence of surgical site infection (SSI, risk ratio (RR): 0.22, p = 0.03). The incidence of delayed graft function was comparable between groups (RR: 1.10, p = 0.82), and the length of hospital stay was similar (MD: -2.03 days, p = 0.21). During a follow-up of 31 months, patients that received RAKT and OKT had similar serum creatinine levels (MD: 10.12 mmol/L, p = 0.42) and similar incidences of graft rejection (RR: 1.16, p = 0.53), graft failure (RR: 0.94, p = 0.79), and all-cause mortality (RR: 1.16, p = 0.77).

Conclusion

Current evidence from nonrandomized studies suggests that RAKT is associated with a lower risk of SSI and similar midterm functional and clinical efficacy compared to OKT. Randomized studies are needed to validate these findings.

Robot-assisted kidney transplantation: update from the European Robotic Urology Section (ERUS) series

OBJECTIVE

To report the results of the robot-assisted kidney transplantation (RAKT) experience performed in 10 European centres by members of the European Robotic Urology Section (ERUS)-RAKT group.

PATIENTS AND METHODS

This is a multicentre prospective observational study of RAKT. Descriptive analysis of recipients and donor characteristics, surgical data, intraoperative outcomes, complications rate and functional results were collected and analysed.

RESULTS

Between July 2015 and September 2019, 291 living-donor RAKTs were performed. Recipients were mostly male (189 [65%]), the mean Standard deviation (sd) age was 45.2 (13.35) years, the mean (sd) body mass index was 27.13 (19.28) kg/m² , and RAKT was pre-emptive in 155 (53.8%) cases. Right and multiple arteries kidneys were used in 15.4%. The mean (sd) total surgical and re-warming time was 244 (70.5) min and 53.16 (15.27) min, respectively. In all, 17 patients presented with postoperative bleeding (5.7%). Five kidneys had delayed graft function; five (2%) were lost due to thrombosis and one due to acute rejection. Two patients had arterial stenosis, three had incisional hernias, six had ureteric stenosis, and nine had lymphoceles. Neither surgical nor re-warming times were correlated with postoperative serum creatinine levels (P > 0.05). Comparison of surgical data between the first 120 cases and the following 171 cases showed a significantly shorter total surgical time in the second group (265 vs 230 min, P = 0.005).

CONCLUSIONS

This is the largest European multicentre study of RAKT with good surgical and functional results competitive with open kidney transplant series, with a relatively short learning curve when performed in centres with a wide experience in open kidney transplantation and robotic surgery.

ABO-Incompatible Robotic-Assisted Kidney Transplantation in the Obese Recipient

Objective: The objective of this preliminary study was to report and compare the peri-operative and functional results of ABO-incompatible (ABOi) living-donor robotic-assisted kidney transplantation (RAKT), ABO-compatible (ABOc) living-donor RAKT, and ABOi living-donor open kidney transplantation (OKT).

Materials and Methods: For the present retrospective study, we analyzed data of consecutive patients who underwent ABOi or ABOc-RAKT and ABOi-OKT, from January 2015 to December 2019, in one French academic center. Patients' baseline characteristics, operative, and functional outcomes were compared between ABOi-RAKT, ABOc-RAKT, and ABOi-OKT.

Results: 29 RAKT, including 7 ABOi-RAKT, and 56 ABOi-OKT were performed in our center. Median follow-up was 2.0 years. Median recipient age, pre-emptive kidney transplantation rate, sex ratio and desensitization procedures were similar in ABOi-RAKT, ABOc-RAKT, and ABOi-OKT groups. Recipient BMI at transplantation was statistically higher in ABOi and ABOc-RAKT groups compared to ABOi-OKT. The surgical site complication (principally infection-related) rate was lower in ABOi-RAKT, without statistical differences (0 vs. 8.9%, respectively, in ABOi-RAKT and ABOi-OKT, p = 0.7). The delayed graft function rate was 0% in ABOi-RAKT, 13.6% in ABOc-RAKT, and 10.7% in ABOi-OKT (p = 0.6). The post-transplantation blood transfusion rate was statistically higher in the ABOi-OKT group (14.3 vs. 13.6 vs. 57.1% in ABOi-RAKT, ABOc-RAKT, and ABOi-OKT, respectively, p = 0.001). The kidney graft survival at 1 month and at last follow-up was not different between ABOi-RAKT and ABOi-OKT.

Conclusion: Our data support the use of ABOi-RAKT to restore accessibility to kidney transplantation for obese patients to the greatest extent possible. Large series are required to confirm these encouraging data from a single center.

Prospective Nonrandomized Comparison Between Open and Robot-Assisted Kidney Transplantation: Analysis of Midterm Functional Outcomes

Introduction: To compare short- and midterm outcomes of the first 55 patients undergoing robot-assisted kidney transplant (RAKT) with patients undergoing open kidney transplant (OKT) during the same period in a tertiary care hospital. Materials and Methods: Data of all end-stage renal disease patients undergoing renal transplant were prospectively maintained. All graft kidneys were harvested laparoscopically. Both RAKT and OKT were performed using standardized techniques, and all RAKTs were performed by a single experienced robotic surgeon. Chi-square test/Fisher exact test was done for categorical data, and Mann-Whitney U test was done for continuous data. Discrete variables were expressed in absolute numbers and percentages. For all tests, p < 0.05 was considered significant. All results were expressed as mean ± standard deviation or median with range. Results: Between April 2016 and September 2018, 55 patients underwent RAKT. The same was compared with 152 patients who underwent OKT. The two groups were comparable in terms of age, gender, and body mass index. Duration on hemodialysis was significantly higher in the RAKT group, and hemoglobin and donor kidney glomerular filtration rate was significantly better in the RAKT group. Requirement of perioperative analgesia was significantly less in the RAKT group. Rewarm ischemia time was significantly longer in the RAKT group. The fall in serum creatinine was slower in RAKT group till 3 months. The serum creatinine levels were statistically similar in the two cohorts at 3 months (p = 0.082), which was maintained at median 29 months of follow-up (p = 0.067). Tacrolimus levels on postoperative day 2 were found to be significantly higher in RAKT cohort (17.98 ± 14.41) vs OKT cohort (11.38 ± 6.93). Surgical-site infections were rare in the RAKT group. Conclusions: RAKT confers advantage of decreased wound morbidity with similar functional outcomes compared with OKT in midterm. It looks promising; however, long-term follow-up of larger numbers of patients is needed.

Robotic-assisted kidney transplantation in obese recipients compared to non-obese recipients: the European experience

PURPOSE

The main objective was to compare minor (Clavien I-II) and major (Clavien ≥ III) intra- and postoperative complications of living donor robotic assisted kidney transplantation (RAKT) in obese (≥ 30 kg/m² BMI), overweight (< 30/ ≥ 25 kg/m² BMI) and non-overweight recipients (< 25 kg/m² BMI).

METHODS

For the present retrospective study, we reviewed the multi-institutional ERUS-RAKT database to select consecutive living donor RAKT recipients. Functional outcomes, intra- and postoperative complications were compared between obese, overweight and non-overweight recipients.

RESULTS

169 living donor RAKTs were performed, by 10 surgeons, from July 2015 to September 2018 in the 8 European centers. 32 (18.9%) recipients were obese, 66 (39.1%) were overweight and 71 (42.0%) were non-overweight. Mean follow-up was 1.2 years. There were no major intra-operative complications in either study group. Conversion to open surgery occurred in 1 obese recipient, in 2 overweight recipients and no conversion occurred in non-overweight recipients (p = 0.3). Minor and major postoperative complications rates were similar in the 3 groups. At one-year of follow-up, median eGFR was similar in all groups [54 (45-60) versus 57 (46-70) versus 63 (49-78) ml/min/1.73 m² in obese, overweight and non-overweight recipient groups, respectively, p = 0.5]. Delayed graft function rate was similar in the 3 groups. Only the number of arteries was an independent predictive factor of suboptimal renal function at post-operative day 30 in the multivariate analysis.

CONCLUSION

RAKT in obese recipients is safe, compared to non-overweight recipients and yields very good function, when it performed at high-volume referral centers by highly trained transplant teams.

Robot-Assisted versus Laparoscopic Donor Nephrectomy: A Comparison of 250 Cases

Living kidney donation is the best treatment for end-stage renal disease, however, the best surgical approach for minimally-invasive donor nephrectomy (DN) is still a matter of debate. This bi-centric study aimed to retrospectively compare perioperative outcomes and postoperative kidney function after 257 transperitoneal DNs including 52 robot-assisted (RDN) and 205 laparoscopic DNs (LDN). As primary outcomes, the intraoperative (operating time, warm ischemia time (WIT), major complications) and postoperative (length of stay, complications) results were compared. As secondary outcomes, postoperative kidney and graft function were analyzed including delayed graft function (DGF) rates, and the impact of the surgical approach was assessed. Overall, the type of minimally-invasive donor nephrectomy (RDN vs. LDN) did not affect primary outcomes, especially not operating time and WIT; and major complication and DGF rates were low in both groups. A history of smoking and preoperative kidney function, but not the surgical approach, were predictive for postoperative serum creatinine of the donor and recipient. To conclude, RDN and LDN have equivalent perioperative results in experienced centers. For this reason, not the surgical approach, but rather the graft- (preoperative kidney function) and patient-specific (history of smoking) aspects impacted postoperative kidney function.

[Robot-assisted kidney transplantation]

BACKGROUND

Robot-assisted surgery has become widely adopted in urology due to advantages in comparison with laparoscopic or open approaches. Robot-assisted living kidney transplantation is one of the most challenging procedures in urology regarding technical, but also psychological and ethical aspects, and is currently routinely performed in two German departments.

OBJECTIVES

The goal was to analyze and compare current evidence and experiences of robot-assisted living kidney transplantation in Europe and in Germany.

MATERIALS AND METHODS

A systematic search was performed to identify relevant publications. They were compared with latest results from two German academic centers (Halle and Homburg/Saar).

RESULTS

In 2015, robot-assisted living kidney transplantation was performed for the first time in Europe. Since then, 8 academic centers have established this procedure. Until today, more than 180 robot-assisted kidney transplantations have been performed. Short- and mid-term results have proven to be excellent with low complication rates. Apart from 3 transplant losses because of arterial thrombosis and 5 surgical re-explorations due to hematoma, no other noteworthy complications occurred. There was only 1 lymphocele. The median blood loss was 150 ml and kidney function after 1 year was unchanged in comparison with postoperative day 30.

CONCLUSIONS

Robot-assisted living kidney transplantation is not inferior to the open approach. Even superiority is not unlikely because problematic situations such as obese patients or complex vascular anatomy can be handled safely. In particular, the development of lymphocele and wound healing disorders appear to be significantly decreased compared to conventional surgery.

Robotic-assisted kidney transplant: a single center experience with median follow-up of 2.8 years

PURPOSE

The main aim of the paper is to report a single-centre experience with RAKT, focusing on surgical, perioperative and functional outcomes at a median follow-up of 2.8 years.

METHODS

Data of 26 RAKT patients was prospectively collected from December 2014 to February 2019 with follow-up of up to 55 months. All donors were done laparoscopically. We followed Vattikuti-Medanta technique with modification of using pfannenstiel incision instead of Gelpoint and patient positioned in steep Trendelenburg position (30°) with leg split position. Hypothermia was maintained using a "modified graft hypothermia jacket". The engrafted kidney is oriented with the vessels being tagged with Prolene sutures.

RESULTS

The mean BMI was 26.1 ± 4.7. The mean warm, cold and total ischemia times were 4.8 ± 1.1, 113.8 ± 20.9 and 118.7 ± 21.2 min, respectively. Mean rewarming time was 62.5 ± 10 min. The mean post-operative day (POD) 1, 3, 7, 30, 6 months, 1 year and most recent creatinine was 3.4, 2.4, 1.8, 1.4,1.2, 1.2 and 1.69 mg/dl. There was no case of delayed graft dysfunction (DGF) with graft survival of 1.8-55 months. The mean GFR at POD 1, 1 month and 1 year was 24, 53.16 and 64.6. We had two intraoperative complications-one topsy turvy graft placement with anastomosis of donor ureter to native ureter and other had to be converted to open technique after anastomosis to control graft surface bleeding. Three postoperative complications-one patient has graft pyelonephritis which was managed conservatively with antibiotics. Two patients had lymphocele. One patient was managed with just aspiration while the other required laparoscopic de-roofing of the lymphocele. The mean hospital stay was 13.5 ± 3 days.

CONCLUSIONS

RAKT is feasible and safe only if performed by surgeons with appropriate background in robotic surgery and kidney transplantation after proper surgical training at experienced centres in the mid-term follow-up. Further studies need to confirm the long-term safety of RAKT.

[Robots in urology-an analysis of current and future devices]

The monopoly of robotic surgical devices of the last 15 years will end in 2019 when key patents of Intuitive Surgical expire. Thus, we can expect an interesting competitive situation in the coming years. Based on personal experience with robot-assisted surgery since 2001, we conducted a search of the current literature together with a search of relevant patents in this field. Finally, we visited the websites of manufacturers of existing and future robotic surgical devices with possible applications in urology. Such devices have to prove that they meet the high-quality standard of the current Da Vinci series (SI, X, XI). For this purpose, we propose to classify the main features of the different devices, such as type of console (closed/open), arrangement of robotic arms (single/multiple carts/attached to operating room table), type of three-dimensional videosystem (by mirror/ocular/using polarizing glasses) or degrees of freedom (DOF) of end effectors (5 vs. 7 DOF). In the meantime, there are also robotic systems used in endourology: Avicenna Roboflex® and the AquaBeam® system for robot-assisted aquablation therapy of the prostate. While Roboflex® improves the ergonomics of flexible ureteroscopy-similar to the Da Vinci robot, AquaBeam® may for the first time eliminate the surgeon, who might only be needed to manage severe postoperative bleeding.