Study Type – Therapy (case series)
Level of Evidence 4
Study Type – Therapy (case series)
To measure the time and subjective quality of individual steps of robot-assisted radical prostatectomy (RARP), as RARP performed by trainees has recently become the most common technique of RP in the USA, and although outcomes from expert surgeons are reported, limited data are available to document training experiences.
PATIENTS AND METHODS
The patients studied were from a prospective cohort of 178 participants (124 with training data). Transperitoneal RARP was performed by one faculty surgeon and one assistant from a rotation of four urological oncology fellows and three residents. RARP was divided into 11 steps, and staff times were recorded for each step. Trainee times and quality scores were recorded for each step, the later defined as grade A equal to staff (A+, no verbal coaching); B, minor corrections; and C, major corrections. Short-term outcomes were recorded to assess the safety of the training.
The mean (range) console time/case of trainees was 40 (10–123) min. The median console time for a complete case by faculty and by trainees (pooled group) was 128 and 231 min, respectively, an increase in 81%. Individual trainee-performed steps increased in time (compared to staff) by a median range of 50–177%, and the incidence of quality grades < A of 9–100%. Trainee quality grades for basic tissue-dissection steps were higher than for advanced tissue dissection and suturing. There was no downgrading for a major correction. Analysis of short-term outcomes suggested acceptable results in a training environment. The study is limited by no available validated training measurement tools, and a low frequency of beginner trainees advancing to more difficult steps during the rotation.
During the initial exposure of trainees to RARP of <40 cases, we measured time and subjective quality grading of basic steps, and introduction to advanced steps. Training requires more procedure time, but does not appear to diminish expected outcomes.
(robot-assisted) (laparoscopic) radical prostatectomy
American Society of Anesthesiologists
positive surgical margin.
The cancer-control and quality-of-life outcomes achieved with radical prostatectomy (RP) are highly dependent on the surgeon’s technique and skill [1,2]. In the hands of expert surgeons, the risks appear to be reasonable for patients seeking cure for clinically localized disease. However, there remains a wide variation in the quality of results achieved across a heterogeneous population of surgeons. Recent reports showed highly variable biochemical disease-free survival and complication rates even within a cohort of expert surgeons [3,4].
Laparoscopic (L) and robot-assisted (RA) techniques have been reported to be acceptable options for surgical treatment, with outcomes from expert surgeons being similar to those of expert open series (acknowledging the limitations of retrospective, non-randomized comparisons) [5–7]. Both approaches use CO2 pneumoperitoneum, resulting in partial tamponade of venous bleeding, and port access resulting in smaller incisions. RA technology adds a three-dimensional camera view and articulating instruments that can facilitate complex tissue dissection and reconstruction. Ahlering et al. reported that the RARP was associated with faster learning than LRP. Whether or not LRP or RARP offer any advantages remains an open question. As yet, due to the lack of high-quality scientific comparisons, one technique cannot be deemed superior to the others . Thus, surgeon experience rather than choice of technique will probably determine outcomes .
At our centre, LRP was used from 2003 to 2006 by one faculty member, while open RP was done by seven (average yearly volume of 350 cases; 14% by LRP). With three or four fellows and three chief residents rotating through 3-month services, the volume of LRP was never enough to teach the complete procedure to an individual trainee. However, with RARP  starting in 2006, and offered by four faculty members, the feasibility of more advanced training became apparent. Therefore, we conducted a pilot project to prospectively collect data on training experiences. In absence of validated training programmes for RARP, we decided to first evaluate the time required for staff vs trainee to perform a step of the procedure and a subjective grading of quality.
PATIENTS, SUBJECTS AND METHODS
During the first 12 months of RARP at our institution, from July 2006 to June 2007, four urological oncology fellows completed a clinical urological oncology fellowship programme. Each of them previously completed urology residency and 1–2 years of basic science rotations. The clinical year included four rotations, each with 1–2 days of outpatient clinic care and 3–4 days of surgery. Each fellow completed a 3-month rotation with one RARP surgeon (J.W.D.) with previous experience of 150 cases before July 2006. This rotation constituted all of the recorded training experience in this report. During other rotations, the fellows assisted three other faculty members who were developing their robotic experience, but this was not included in the current report due to minimal console time. In a minority of instances, a rotating resident was assigned to a case (three different residents in last 2 years of training), and if console time was awarded, they were evaluated the same as a fellow. In this report, we pooled the results of fellows and residents. For all cases we used the standard model four-arm daVinci robot (Intuitive Surgical, Sunnyvale, CA, USA), i.e. no graphic illustration function, as seen in the S-model. The access was transperitoneal.
At the beginning this study, there were no validated training tools for RARP and thus we created our own. The RARP procedure was divided into 11 steps, as shown in Table 1. We evaluated the trainees independently for time to complete a procedure step (objective evaluation) and quality of results (objective and subjective evaluations). The quality grading system was as follows: A+, quality equal to staff with minimal coaching (verbal or visual); A, equal to staff with coaching; B, minor correctable errors; and C, major errors requiring complex correction. Staff comments on the trainee’s work were recorded as needed, to explain grades and to provide feedback. It was unknown as to which order these steps should be taught; rather, staff awarded console time to the trainee based on past experience and performance with the overall goal of the trainee performing as many steps as feasible in the context of a fixed 2–3 month rotation. When trainees were at the console, the staff (J.W.D.) assisted at the bedside, providing continuous instruction and control of the case. In general, basic tissue dissection and suturing had to be learned before advanced tissue dissection and suturing. A detailed description of the RARP technique taught to trainees is given in Appendix 1 and available as a weblink at http://www.mdanderson.org/RARP-Technique. For reconstruction we used a running 2–0 monofilament suture, as described by Van Velthoven et al.. Pelvic lymph node dissections done during this era were obturator-zone dissections, although we have subsequently adopted extended zones.
|Step||Median time, min||No. of trainee- performed steps||Staff vs trainee time, P||Trainee steps|
|Staff||Trainee||% increase time||% with score ≤B|
|Dorsal vein complex||9||25||25||<0.001||177.8||72|
|Anterior bladder neck||5||10||24||<0.001||100.0||17|
|Posterior bladder neck||7.5||14.5||22||<0.001||93.3||32|
|Pedicles, one side||18.5||29||17||0.026||56.8||41|
We obtained Institutional Review Board approval to collect clinical and demographic data on patients treated with RARP by one surgeon (J.W.D.) during the 2006–2007 academic year, and for subsequent years by additional surgeons involved in training. Training data-collection sheets included descriptors for case difficulty: prostate size, median lobe, obesity, previous abdominal surgery, hormonal use, and nerve-sparing strategy. A departmental database was queried to identify all complications and findings categorized as per Badani et al. RARP specimens were evaluated by one genitourinary pathologist .
We used the Kruskal–Wallis test  to compare the operative times for the trainees at each step in the RARP procedure. The operative times for J.W.D. and the trainees (as a group) are reported as the median. We summed the medians for each step for J.W.D. and for each trainee to determine the total time for the RARP procedure. We divided the median operative time of the trainees by that of J.W.D. for each step to give a measure of how much longer the fellows took than J.WD. to complete that step of the procedure. The percentage of grades B or worse are tabulated for each step.
Table 2 shows the demographic characteristics of the 178 patients who had RARP by one surgeon during the 2006–2007 academic year. Although patients were selected as appropriate surgical candidates, many might not be considered ideal cases for training; 40% were class 3 by the American Society of Anesthesiology (ASA) classification system , 43% were overweight, and 31% were obese. Cases were classified at the time of surgery as ‘more difficult’ for reasons such as obesity (18, 10%), hormone therapy (four, 2%), large bladder neck (35, 20%), median lobe (10, 6%), and abdominal adhesions (16, 9%).
|Characteristic||Median (range) or n (%)|
|Age, years||59 (40–76)|
|African American||19 (11)|
|Native American||1 (<1)|
|Body mass index, kg/m2||28.2 (20–54.7)|
|18.5–24.9 (normal)||38 (21)|
|25–29.9 (overweight)||76 (43)|
|30–34.9 (Obese I)||37 (21)|
|35–39.9 (Obese II)||14 (8)|
|>40 (Obese III, morbid)||3 (2)|
|TRUS volume, mL||32.2 (14.2–90.3)|
|Total PSA level, ng/mL||5.6 (1.2–67)|
|3 + 3||56 (31)|
|3 + 4||76 (43)|
|4 + 3||26 (15)|
|≥4 + 4||20 (11)|
|Surgical planning by risk group|
Table 2 also shows the preoperative diagnostic findings of the group. Patients selected for the procedure included those with prostates of >60 g, and those with low- to high-risk disease. Most patients had nerve-sparing surgery, unilateral at minimum and bilateral more commonly; bilateral non-nerve-sparing was infrequent, even in patients with high-risk disease. Pelvic lymph nodes were dissected in all patients in the high-risk category, in those in the intermediate-risk category who had dominant Gleason 4 biopsies, or any patient with a PSA level of >10 ng/mL.
Table 3 shows selected early outcomes; although discharge on the first day after RARP was feasible, 62% of patients went home on the second day. The median volume of blood loss was 200 mL and the median decrease in the haemoglobin level from baseline to the first day after RARP was 2.0 g. There were no intraoperative transfusions, and only one transfusion was required in the 30-day period after RARP. Complications were <10% overall, with no grade IV or V events. Pathological findings included organ-confined disease in 81% of patients and positive surgical margins (PSMs) in 12.4%. On pathological analysis, there were PSMs in 7%, 29% and 50% of patients with stages pT2, pT3a, and pT3b, respectively. Nerve-sparing was feasible in many cases, due to rates of organ-confined disease; 100% for prostatectomy Gleason 3 + 3, 89% for Gleason 3 + 4, 67% for Gleason 4 + 3, and 35% for Gleason 4 + 4 (provided the preoperative PSA level was <10 ng/mL).
|Varaible||Median (range) or n (%)|
|Length of stay, days||1.8 (1–6)|
|Discharge after, days|
|Operating room time, h||5.2 (2.9–7.6)|
|Procedure time, h||4.1 (2.1–6.3)|
|Estimated blood loss, mL||200 (35–850)|
|Preoperative haemoglobin level, g/dL||14.1 (8.6–18.1)|
|day 1 after RARP||11.7 (8.9–14.3)|
|After RARP||1 (0.6)|
|Complications, 30 day||17 (9.6)|
|I (minor deviation)||7 (3.9): neuralgia (1), retention (3), haematuria (1), false passage (2) 5 (2.8): DVT (1), MI (1), ileus (2), gastroparesis (1)|
|II (pharm./bedside treatment)||5 (3.9): anastomotic failure (1), BNC (1), abscess (1), lymphocele (1), haematuria/clot (1)|
|IV (life threatening, residual deficit)|
|pT0||1 (<1%)/PSM 0|
|pT2a-c||141 (79)/PSM 10 (7)|
|pT3a||28 (16)/PSM 8 (29)|
|pT3b||8 (4)/PSM 4|
|PLND, median (range) count|
|N0||85 (48), 8 (1–37)|
|N1||6 (3), 9.5 (4–19)|
|Organ confined pathological stage by Gleason score (PSA <10 ng/mL)|
|3 + 3||17/17 (100)|
|3 + 4||85/95 (89)|
|4 + 3||26/39 (67)|
|≥4 + 4||6/17 (35)|
For the four fellows covering all clinical services, RARP accounted for 40% of their RP experience and 15% of their major cases. RARP training data were collected in 124 (70%) of the 178 cases performed by J.W.D. during the study period. In 30 of these 124 (24%), there was no trainee console time due to circumstances including case complexity, late hours, or limited trainee experience. The median (range) trainee console time was 40 (10–123) min. The distribution of cases per trainee was: fellow 1, 37; fellow 2, 26; fellow 3, 13; fellow 4, 29; and rotating residents, 19. The median console times of staff and trainees for each step of the RARP procedure are shown in Table 1 and Fig. 1. Trainees’ results were pooled, because the Kruskal–Wallis test showed no statistically significant differences among individual trainees. For the trainee group, basic tissue dissection steps, such as dissecting the bladder off of the anterior abdominal wall or endopelvic fascia division, were performed more frequently than advanced dissection/suturing steps, such as dividing the urethra or sewing the posterior anastomosis. The median complete case console time for staff was 128 min and for trainees was 231 min, representing a median 81% increase. For individual steps, the increase in time ranged 50–177%.
The far right column of Table 1 shows the percentage of trainee-performed steps that were downgraded to a B (C grades described but not assigned). For example, the ‘bladder drop’ step was downgraded only 9%, indicating a higher quality performance, whereas oversewing of the dorsal vein was downgraded 72%, indicating a more challenging task. Optional specific feedback was also recorded to describe the reason for downgrading: haemostasis (seven), dorsal vein complex knot too loose or plane suboptimal (nine), anterior bladder neck too large (10), posterior bladder dissection plane incorrect (two), awkward sewing motions (i.e. broken stitch or needle) (seven), and prostate capsule violation (one). Informally, trainees were asked to provide feedback for staff; a noteworthy comment was a preference to perform the same console steps on all cases on a given operating day, to reinforce their learning and efficiency with those steps.
The use of RA surgery for prostate cancer has increased dramatically since 2003, and the operation has steadily grown from a procedure only performed by staff urologists to one being taught to urologists-in-training. Robotic surgery training has a markedly different set-up and feel for the teacher. The surgeon-in-training at the console is physically removed from the patient’s side and has dominant control of the operating instruments and camera, while the patient-side surgeon (even if a staff member) has limited control of the field. Nevertheless, the articulating motion of the instruments and three-dimensional camera view have been cited as reasons why the learning curve is enhanced for staff  and the same might apply for surgeons-in-training. In this pilot study, we aimed to assess our ability to teach specific steps of the RARP, as well as evaluate the programme as a whole and provide an assessment of needs for further training.
Our data show that when a trainee has experience with <40 cases, many steps perceived by staff as basic/introductory can be performed fairly well, but take significantly longer. In some cases, advanced steps can be attempted, but it is likely that far more than 40 cases will be required to correct minor mistakes and to train a new surgeon adequately in all steps. The subjective grading and feedback process might provide groundwork for more formal evaluations and ultimately a validated curriculum.
For teaching to take place, excellent patient outcomes must be documented in this environment. Our complications were reported with the methods used by Badani et al., from the experience at Henry Ford Hospital with >2500 procedures. They reported class I-V complication rates of 8%, 3.7%, 0.5%, 0.01% and <0.01%. Our complication range was similar (3.9%, 2.8%, 3.9%, 0% and 0%), and PSMs were 12.4% overall and 7% for pT2 disease. This comparison would suggest that training occurred while maintaining quality outcomes. Safety is also suggested by the absence of any major corrections, and of minor corrections, only the one instance of capsule violation (surgical plane corrected by staff with negative margins) would be relevant to long-term outcome. We report only short-term easily obtainable outcomes, while collecting data on long-term quality-of-life outcomes. Safety has also been reported by the study by Schroeck et al., who showed no difference in estimated blood loss and PSM rates in a training centre.
The strengths of this study are the prospective collection of training data, confirmation of patient safety and outcomes in a teaching environment, and the proposed early effort to measure surgical skill training. Training continues to develop as entering fellows and rotating residents start with more previous robotic experience, and the number of faculty members participating in console training has increased from one to four. Furthermore, when a trainee is downgraded for performance, he or she can learn from the event and improve in the future, but at the same time, the staff might learn subtle methods of teaching that will help the next training event to achieve a satisfactory evaluation. We have no set guidelines as to when faculty members should start trainees on the console, but have observed a comfort level after 50 cases (sooner with previous laparoscopic experience).
The limitations of this study include the fact that we used subjective and as yet unvalidated evaluations as a measure of the trainee’s performance. In addition, a set sequences for how to guide a trainee through the steps of the operation has not been determined. Table 4 lists the goals we set for them at the beginning of the rotation and as we discuss training steps, and each point could potentially be part of a formal evaluation process.
|Training level||Benchmarks of success||Pitfalls to avoid|
|Assistant role||Port placement||‘Over-clipping’: clipping more tissue than given|
|Efficient docking of the robot||Losing needles|
|Efficient manipulation of arms/instruments||Ineffective suctioning|
|Accurate clip placement||Inability to anticipate retraction needs|
|Troubleshoots camera cleaning, arm collisions|
|Console role: basic tissue dissection and suturing|
|Bladder drop||Efficient use of all 3 arms, toggles 4th arm efficiently. Recognizes and controls small vessels before dividing.||Instrument collisions, avulsing vessels|
|Endopelvic fascia||Divides fascia, puboprostatic ligaments, controls superficial DVC. Complete apical mobilization to optimize success of DVC suture.||Avulsing vessels perforating the prostate apex at 10 o’clock and 2 o’clock position. Avoids avulsing the superficial DVC, Avoids cautery around nerve bundles.|
|Anterior bladder neck||Demonstrates knowledge of landmarks between prostate and bladder neck. Divides tissues and controls bleeders.||Avoids dissection into prostate. Avoids excessively large bladder neck.|
|Backbleeding suture||Demonstrates needle control, efficient and tight square knotting.||Avoids air knots, breaking suture.|
|Anterior anastomosis||Careful suture placement, tightening the suture line, final square knot.||Inadequate suture placement – depth and/or travel, breaks needle or suture. Tears urethra.|
|Console role: Advanced tissue dissection and suturing|
|Posterior bladder neck||Demonstrates knowledge of proper dissection plane between prostate and bladder. Identifies distance to trigone.||Avoids dissecting into prostate or button-hole back into bladder. Avoids cautery laterally near nerve bundles.|
|Seminal vesicles||Dissects vas/seminal vesicles intact. Mobilises arteries around seminal vesicles for clipping.||Avoids avulsing vas or SV. Avoids cautery at seminal vesicle tips.|
|Pedicle division||Demonstrates ability to identify, mobilize, and clip perforating bladder and prostate pedicles. Sharp dissection of lateral prostatic fascia without capsule injury.||Avulsion of vessels while mobilizing a packet. Failure to recognize plane between nerve bundle and prostate.Non-nerve sparing – avoids rectum.|
|Urethra division||Mobilizes urethra sparing length back to verumontanum, spares surrounding sphincter complex.||Passing the Maryland through the urethra rather than around. Avoids dissection into apex|
|Dorsal vein suture||Recognizes groove between DVC and urethra. Needle control to pass around DVC without landing in prostate or lateral sphincter.||Air knots, plane too shallow, causing too much bleeding.|
|Posterior anastomosis||Demonstrates ability to pass the initial posterior urethra bites: includes mucosa and sufficient rhabdosphincter.Parachutes posterior suture line tight.||Struggles with initial needle control, bites to shallow, injures with needle or suture.|
The study of Schroeck et al. also sought to study the results of RARP in a training centre, and is the first published report on this topic. Their design was different from ours, in that the procedure was divided sequentially into thirds and trainees were advanced in order from assistant only to part one, three, and then two. We have also found that the ideal sequence of training might not be sequential, but could be in different parts of the case and/or might depend upon the particular features of a case. For example, for a patient with a very large gland and a novice trainee, the anastomosis might be selected for training, whereas for a normal size gland, the bladder neck might be selected. In the early cases of training, the mentor should select steps for the trainee to perform that can easily be reversed or corrected by the mentor, who should be scrubbed as the bedside assistant and have a suction device and grasper to use to point and expose. Also, if the bedside surgeon presses the clutch button on the camera arm, then all working arms are frozen – a driver’s education ‘brake.’ Steps that can easily be corrected or reversed include dropping the bladder, endopelvic fascia, dorsal vein suturing, anterior bladder neck, and anterior anastomosis. With time and freedom from downgrading, more sensitive steps that are harder to reverse can be selected, such as posterior bladder, nerve bundles and apex. We are currently collecting data that groups the 11 steps of the operation into ‘skill sets’: basic tissue dissection, advanced tissue dissection, bladder neck and sewing. The goal then becomes to balance the trainee’s console steps among these skill sets. As trainees enter the rotations with more previous experience, they can increase in console time and/or complex steps, i.e. a more challenging bladder neck. In the opinion of the staff, our early experience with robotic training appears to be far more productive than a similar exposure of trainees to pure LRP from 2003 to 2006; however, similar data on trainee experiences with LRP were not collected.
Our first year of robotic training shows that while we were able to teach the introductory steps for most trainees, the exposure to advanced steps were more limited, and arguably incomplete (especially fellow 3, with <20 cases due to rotating at the very beginning of the programme). On the other hand, these trainees received far more training than seen in the community, where newly trained surgeons can obtain credentials after case observation, three or more proctored cases, but no required formal teaching. The American Council on Graduate Medical Education residency guidelines evaluate residents based on six core clinical competencies: patient care, medical knowledge, professionalism, interpersonal/communication skills, practice-based learning, and systems-based practice . Future developments of validated surgical training curricula might be valuable additions to such core competencies.
Several additional features of robotic surgery training were noted but not shown in these data. Table 1 shows that if a trainee performed a complete procedure, the procedure time would be lengthy, and we often limited trainee console time to 30 min. However, these data are specific to the programme’s first year, and we anticipate increasing trainee opportunities. The addition of a full-time patient-side surgical assistance would also increase training opportunities by avoiding the downtime of staff and trainees scrubbing into and out of the case. Although the technology provides a well-magnified and ergonomically comfortable environment for the console surgeon, the bedside assistant’s position by comparison is less well equipped. Most standard video monitors are two-dimensional and have lower resolution than the console. In the circumstance of the trainee dissecting the posterior bladder neck, it can be difficult for the staff to tell from the assistant’s monitor whether the trainee is in the correct plane. This accounted for minor corrections needed in this area. Future equipment upgrades, especially in the academic setting, should aim to equalize the quality of vision for both surgeons. We recommend one other equipment upgrade currently installed into our robotic suite, i.e. two-way wireless microphones for the console and patient-side surgeon (some newer systems have this built in). This system significantly enhances verbal communication, especially from the console surgeon, whose voice is muffled by the device.
Effective RARP training requires a high degree of patience and confidence. Such patience is challenged in our everyday practice because there are relatively fewer ‘ideal training cases.’ Most patients have one or more features that add additional challenges to training: nerve-sparing surgery, morbid obesity, previous hormonal therapy, and high-risk pathology features. Our training environment probably represents what occurs in the ‘real world’; the bulk of trainee experience is derived from live-case exposure. We can envision that dry laboratory exercises and/or animal laboratory dissections will expedite learning, possibly by dedicating a robot specifically for training. Surgical simulation might play a role in the future, as could the new dual-console daVinci Si model robot; however, neither are widely available at present. Even if surgical simulation is available, prostate anatomy is subtle and complex, and we predict that there will always be a need for effective live-case instruction. Significant barriers to off-line instruction include unclear sources of funding, and many competing interests for mentors’ and trainees’ times.
The study of Vickers et al. quantifies the well known feature of open RP; a difficult and lengthy learning curve. Therefore, the significance of this and ongoing related studies will be to determine whether the robotic surgery environment can better equip all surgeons to improve the quality of results for patients choosing a surgical cure. In the near future, we expect to collect enough training data to compare the performances and training needs of different groups of surgeons, i.e. residents, fellows with minimal resident robotic experience, fellows with significant resident robotic experience, and staff converting from open to laparoscopic background. In the meantime, we offer Table 4 as a descriptive strategy for surgeons participating RARP training.
In conclusion, RARP training at a high-volume centre is possible in an environment which facilitates quality patient outcomes if implemented in a systematic, progressive manner; trainees require a median of 81% more time to complete steps than staff; the frequency of minor downgrading varies with the complexity of the step; and performance of all steps was not uniformly obtained in <40 cases.
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