Surgical Endoscopy (2021) 35:4183–4191 and Other Interventional Techniques https://doi.org/10.1007/s00464-020-07899-5 Evaluation of a remote‑controlled laparoscopic camera holder for basic laparoscopic skills acquisition: a randomized controlled trial Mohammad S. A. Amin1 · Abdullatif Aydin1 · Nurhan Abbud1 · Ben Van Cleynenbreugel2,9 · Domenico Veneziano3,9 · Bhaskar Somani4,9 · Ali Serdar Gözen5,9 · Juan Palou Redorta6,9 · M. Shamim Khan1,7 · Prokar Dasgupta1,7 · Jonathan Makanjuoala8 · Kamran Ahmed1,8,9 Received: 23 May 2020 / Accepted: 17 August 2020 / Published online: 26 August 2020 © The Author(s) 2020 Abstract Background Unsteady camera movement and poor visualization contribute to a difficult learning curve for laparoscopic surgery. Remote-controlled camera holders (RCHs) aim to mitigate these factors and may be used to overcome barriers to learning. Our aim was to evaluate performance benefits to laparoscopic skill acquisition in novices using a RCH. Methods Novices were randomized into groups using a human camera assistant (HCA) or the FreeHand v1.0 RCH and trained in the (E-BLUS) curriculum. After completing training, a surgical workload questionnaire (SURG-TLX) was issued to participants. Results Forty volunteers naïve in laparoscopic skill were randomized into control and intervention groups (n = 20) with intention-to-treat analysis. Each participant received up to 10 training sessions using the E-BLUS curriculum. Competency was reached in the peg transfer task in 5.5 and 7.6 sessions for the ACH and HCA groups, respectively (P = 0.015), and 3.6 and 6.8 sessions for the laparoscopic suturing task (P = 0.0004). No significance differences were achieved in the circle cut- ting (P = 0.18) or needle guidance tasks (P = 0.32). The RCH group experienced significantly lower workload (P = 0.014) due to lower levels of distraction (P = 0.047). Conclusions Remote-controlled camera holders have demonstrated the potential to significantly benefit intra-operative per- formance and surgical experience where camera movement is minimal. Future high-quality studies are needed to evaluate RCHs in clinical practice. Trial registration ISRCTN 83733979 Keywords Robotic camera holder · Laparoscopy · E-BLUS · Surgical skills · Human error Many technical limitations of laparoscopic surgery are demand, and reduces performance [8–10]. Furthermore, overcome with robot-assisted surgery, but due to socioeco- errors made by human camera assistants (HCAs) due to nomic factors laparoscopy remains the favoured modality inexperience, miscommunication, tremor, involuntary rota- for many trusts [1]. However, despite laparoscopy’s wide- tion of the camera’s axis, erroneous movements, and fatigue spread application most research has focused on improving contribute to an unsteady camera image which can also robot-assisted surgery. As such, some of the disadvantages reduce surgical performance [5, 9, 11–17]. of laparoscopic surgery e.g. operation duration, complica- Improvements to camera assistance may facilitate a tion, and mortality still exist and may be improved upon by shorter learning curve so trainee surgeons can gain com- addressing the challenges of the learning curve (LC) [2–7]. petency quicker to treat patients. In the 1990s prior to the Laparoscopy’s difficult LC is attributed to the increased advent of telesurgical robots, remotely controlled robotic workload when compared to open surgery as maintaining camera holders were introduced to produce stable images challenging physical positions increases stress, physical and fewer inadvertent movements, [5, 10, 11, 15, 16, 18, 19]. As remote-controlled camera holders (RCHs) eliminate tremor, camera rotation, and muscular fatigue they may be * Kamran Ahmed Kamran.ahmed@kcl.ac.uk advantageous when compared to conventional HCAs. Extended author information available on the last page of the article 13 Vol.:(0123456789) 4184 Surgical Endoscopy (2021) 35:4183–4191 However, few high-quality studies have taken place evalu- laparoscopic skills (E-BLUS) curriculum were practiced ating their performance benefits. (Fig. 1). This study aims to evaluate the benefits of a RCH and by All participants attended a mandatory induction course mapping it’s LC, identify potential challenges experienced for theoretical teaching and demonstration of technique [2, 3]. required to pass E-BLUS tasks. Skill demonstration was performed by MSAA and NA who were trained in laparo- scopic technique and E-BLUS competent. The opportunity Materials and methods to ask questions on E-BLUS and camera holding technique was given [2, 21]. Supplementary e-learning resources on Trial design LS theory and technique for performing E-BLUS tasks were distributed [3]. This study was a prospective randomized controlled trial Skill sessions were modelled on a training curriculum designed according to the Consolidated Standards of Report- for simulated laparoscopic cholecystectomy in novices ing Trials (CONSORT) 2010 guidelines [20]. Novice partic- [2]. Tasks were performed once per skills session with a ipants (medical students naïve in laparoscopic theory, lapa- limit of two per day with no opportunity for warmup [22]. roscopic practical skill, and camera holding) were enrolled One-hour breaks were implemented between sessions with onto a basic laparoscopic skills (BLS) training course where a maximum of ten being offered [2, 4, 23, 24]. Terminal the four tasks of the validated European training in basic participant-specific feedback was consistently provided by Fig. 1  Individual tasks of the European Training In Basic Laparoscopic Urological Skills (E-BLUS) curriculum. a Peg transfer. b circle cutting. c needle Guidance. d laparoscopic suturing 13 Surgical Endoscopy (2021) 35:4183–4191 4185 the skill demonstrators to remind participants the appropri- least two consecutive sessions [2]. To map the learning curve ate technique and to increase economy of movement [4, 25]. an expert developed, performance improvement (Pi) score Trial participants were also used as HCAs in the con- described by Veneziano et al. was used [25]. The Pi score trol group to replicate the conventional practice of having a measured skill by comparing task duration and errors made, human hold the laparoscope. Initially naïve in camera hold- to previous performances in relation to the required pass mark ing, all novices received the same level of dedicated training [25]. It was not feasible to use blinded outcome assessors as during a mandatory induction course to standardize their the smooth movement and absence of tremor from the RCH impact to participants’ performance during skills sessions. would be easily discernible. Thus, the outcomes were assessed As best to our knowledge, no data exist on when camera by the skill demonstrators. competency is achieved so this was practiced until HCAs reached a proficient standard determined by their ability to Secondary outcome efficiently visualize all possible areas of the box trainer with appropriate technique. The secondary outcome was the surgical workload experi- enced by participants measured by the validated SURG-TLX Intervention and materials questionnaire distributed after the final skills session [8]. E-BLUS tasks were performed using training platforms Sample size and randomization (Intech, Calabria, Italy), folded gauze with printed circles, and penrose drains (Limbs & Things, United Kingdom). 4–0 As no data on E-BLUS learning curves have been previ- polypropylene sutures were used for needle guidance and ously published, we estimated that benefits of the RCH would suturing. decrease the required number of skills sessions to gain compe- The experimental group used the FreeHand® v1.0 RCH tency from six to four. These variables were used in a sample (FreeHand Ltd, Guildford, United Kingdom) which is size calculation for a test comparing two independent means favoured by surgeons and free of safety concerns (Fig. 2) [5, at an alpha level of 0.05 and power of 80%. Using StataIC 15 10, 18]. It is a robotic arm specifically designed for holding (StataCorp, Texas, USA), the calculation yielded a size of six laparoscopes and cable of movement in 3 planes. It was con- participants in each group. The number of participants was trolled with a joypad by a human operator and was moved raised to 20 in accordance with methods of a previous learn- only under direct instructions of the participant. ing curve study to accommodate for dropout and increase trial The RCH requires minimal practice to gain competency accuracy [2]. Limitations to study resources prevented further and so operators practiced until they felt comfortable [16, participants from being recruited into the BLS course and this 18]. A supplementary guide on how to use the RCH was study. also issued. 60 eligible participants were randomly selected from the recruitment form and block randomized into three groups at a Outcomes ratio of 1:1:1: via randomizer.org. Groups were then randomly assigned control or intervention status. Only the control group Primary outcome and one intervention group are the focus of this study. Enrol- ment of participants, assignment of interventions, and rand- The primary outcome was the time taken to reach competency omization of participants were performed by MSAA. Partici- in E-BLUS tasks, defined as maintaining the pass score for at pants were blinded to randomization but not the intervention. Statistical methods Unpaired t tests were used to compare the scores of both the groups to identify statistical significance between primary and secondary outcomes. To exclude unreliable reporting of results from the SURG-TLX questionnaire, outlier scores were removed prior to unpaired t tests [26, 27]. Fig. 2  A participant using the FreeHand automated camera holder 13 4186 Surgical Endoscopy (2021) 35:4183–4191 Results participants completed all 10 skill sessions or were lost to follow-up. Participant flow and recruitment Baseline data The skills course received 112 applications of which 60 were evenly randomized into one control and two interven- Demographic data were collected from participants via tion groups. The participants who were not randomized the recruitment form. This consisted of age, gender, year into the RCH or HCA groups were allocated a different of medical study, previous laparoscopic experience, and intervention which used the Microsoft HoloLens and do interest in laparoscopic skill. Differences in demographics not form part of this trial. All participants in both groups between groups were not statistically significant (Table 1). received their allocated intervention with 13 partici- pants from the control group and 10 from the interven- Primary outcome: basic laparoscopic skill tion group completing all 10 sessions. Data were gathered for intention-to-treat analysis for which data from all 40 The initial Pi scores were similar for both groups in all participants were analysed (Fig. 3). The trial ended when tasks (Fig. 4). In the peg transfer (PT) task, the RCH Fig. 3  Consort 2010 flow diagram of participants for the primary outcome 13 Surgical Endoscopy (2021) 35:4183–4191 4187 Table 1  Demographic data of Characteristic Human camera assistant Remote-controlled camera trial participants group (HCA) n = 20 holder group (RCH) n = 20 Mean age (range) 21.8 (18–28) 21.2 (18–26) Gender Male: 6 Male: 8 Female: 14 Female: 12 Year of medical study 1st: 5 1st: 5 2nd: 3 2nd: 5 3rd: 9 3rd: 7 4th: 2 4th: 2 5th: 0 5th: 0 6th: 1 6th: 1 Laparoscopic interest Yes: 20 Yes: 20 No: 0 No: 0 Undecided: 0 Undecided: 0 Previous laparoscopic experience (theoretical, Yes: 0 Yes: 0 practical, laparoscope holding) No: 20 No: 20 Fig. 4  Learning curves of the European training in basic laparoscopic urological skills (E-BLUS) tasks. a Peg transfer. b circle cutting. c Needle guidance. d Laparoscopic suturing 13 4188 Surgical Endoscopy (2021) 35:4183–4191 surpassed the HCA at the 3rd mean session and gained Table 3  Average scores of the SURG-TLX questionnaire broken competency significantly faster at 5.5 and 7.6 mean ses- down by domain for the human camera assistant (HCA) and Remote- controlled camera holder (RCH) groups sions, respectively (P = 0.015) (Table 2). In the circle cutting (CC) task, both groups experienced widespread Domain HCA RCH P value plateaus. By the 5th mean session, the HCA held a deci- Mental demand 26.60 26.50 P = 0.5 sive lead over the RCH. Only four participants of the Physical demand 46.60 33.67 P = 0.093 HCA group gained competency compared to the two Temporal demand 35.20 42.17 P = 0.21 of the RCH group. This difference was not statistically Task complexity 34.00 32.33 P = 0.44 significant (P = 0.18). Both groups progressed rapidly in Situational stress 24.40 25.17 P = 0.46 the needle guidance (NG) task. After the 4th mean ses- Distractions 29.00 10.83 P = 0.047 sion, the HCA surpassed the ACH, however, by the 8th Total workload score 195.80 170.67 P = 0.014 mean session, the RCH had an overall score of 58.3 to the HCA’s 45.3. There was no significant difference in the RCH gaining competency by 4.7 mean sessions com- pared to a mean of 5 sessions of the HCA (P = 0.32). In Discussion the laparoscopic suturing (LS) task, the RCH performed consistently better than the HCA. The HCA group expe- The trial successfully produced a learning curve of basic rienced three plateaus, whereas the RCH group only had laparoscopic skills and demonstrated the skills course was one. The RCH group was significantly faster in reaching effective for all participants to reach competency in the PT, competency at a mean of 3.6 sessions whilst the HCA NG, and LS tasks. The largest changes in Pi scores were group needed a mean of 6.8 sessions (P = 0.00038). seen by the first three sessions as more than 50% of the final Pi value had been achieved. Studies suggest that the large initial increases to Pi score is due to refinements in accuracy Secondary outcome: surgical workload which reduces errors shortly followed by improvements to time efficiency [21, 25, 28, 29]. Ten participants from the control group and 13 partici- The advantages provided by the RCH were evident from pants from the intervention completed the SURG-TLX the marginal increase in initial task scores when compared questionnaire. One outlier from the intervention group to the HCA group. This was further emphasized by the dif- was removed prior to analysis. Analysis of the remaining ferences in time taken to competency which significantly data was then performed (Table 3). Total workload score favoured the RCH group for PT and LS tasks, whereas for the RCH group was 170.7, whereas the control group CC and NG had no significant differences. In the CC task, scored 195.8 (P = 0.014). In the distraction domain, the the HCA had a higher Pi score than the RCH. Yet, most RCH group scored 10.8 whilst the HCA group scored 29 participants did not gain competency and it took at least achieving borderline significance (P = 0.047). eight sessions for those who did make it the most difficult E-BLUS task. This difficulty could be attributed to the cir- cle folding back on itself requiring constant reorientation of Harms the scissors. It was expected that tasks would have different LCs as they each required a different combination of skills Some participants experienced temporary anxiety and which both cohorts would have different advantages in e.g. stress when committing errors or finding it technically a fixed camera position would have optimized speed in the difficult to complete a task. Some participants also expe- PT task so it is unsurprising for the RCH group to have rienced tiredness and muscular fatigue as they were not performed significantly better here. Performance during PT accustomed to laparoscopy. also benefited by having a view of the entire operative field Table 2  Average number of Task Sessions taken to reach compe- Sessions taken to reach compe- P value sessions required to reach tency using RCH (range) tency using HCA (range) competency in individual E-BLUS tasks for the Remote- Peg transfer 5.5 (2–9) 7.6 (4–10) P = 0.015 controlled camera holder (RCH) Circle cutting 10 (10–10) 9.25 (8–10) P = 0.18 and human camera assistant (HCA) groups Needle guidance 4.7 (2–9) 5 (3–9) P = 0.32 Laparoscopic suturing 3.6 (1–7) 6.8 (4–10) P = 0.00038 13 Surgical Endoscopy (2021) 35:4183–4191 4189 which similarly improved performance in LS as participants to increased decision making, anatomical recall, and proce- were more capable of simultaneously tying both ends of the dure complexity [4, 24, 30]. The ensuing benefits would be suture. Maintaining the same advantageous perspective cost efficiency to surgical training as the surgeon can focus would have been physically difficult for a HCA further con- on teaching rather than camera handling, additionally clini- firming that improper camera control is a limiting factor in cal practice would improve as the assistant would be free laparoscopic performance. to attend to patients in wards or clinics [2, 5, 9–11, 18, 19]. Improvements in task performance may have been con- The trial’s primary strength is the robust skills programme tributed by decreased surgical workload as the RCH group designed to optimize learning, performance, and retention of experienced lower levels of distraction. This may be due skill. This was achieved by reviewing high-quality studies of to team members in the HCH group physically obstructing educational techniques e.g. preventing fatigue and methods each other when repositioning to complete tasks, a problem for delivering feedback. Furthermore, randomizing a large not encountered with the RCH allowing for constant focus cohort of participants and measuring outcomes over many [10]. This finding was in contrast to a study by Wijsman training sessions served to increase accuracy. Additionally as et al. using a different RCH where the workload in a clinical both cohorts had insignificant differences in their ages their environment was not affected, a potential reason for this was LS ability would have been unchanged [24]. the use of the NASA-TLX and not the modified SURG-TLX Participants were not screened for previous open sutur- as used in this study [10]. ing experience as there is little transfer into laparoscopic In the NG and CC tasks, the camera angle was continu- skill, however, previous suturing experience may have been ously changed as different regions required visualization. advantageous in understanding LS technique. This risk was As humans are much faster in moving the camera this trial minimal due to cohorts being large, randomized, and con- shows that the RCH is slightly disadvantaged in situations taining junior medical students where suturing experience is where constant movement is necessary [16]. To minimize uncommon. Additionally, as two demonstrators were used, time loss from repositioning the optimum perspective should learning for individual students may have been different. be found to encourage economy of movement. This mini- However, this too was mitigated as tutors agreed on tech- mizes the number of camera movements required and allows nique prior to teaching. Furthermore, as the demonstrators for continuous cutting to maximize time efficiency. Further- also assessed the outcomes of the study and were not blinded more, participants encountered barriers to performance in to the intervention there is a potential risk of bias. This bias the NG task as the needle frequently bent contributing to was reduced by assessors strictly adhering to the official task difficulty. Emphasis should therefore be made to teach E-BLUS guidance on when a task begins, is completed, and appropriate needle handling technique. what constitutes an error. As no definitive plateaus were reached within the ten skill The use of trial participants as both laparoscopic novices sessions further studies to identify the point of task mastery and human camera assistants may have introduced risk of may prove to be beneficial in preparing for more advanced bias to the study as partaking in one task may have enhanced tasks [30]. However, the temporary plateaus and dips in the skill in the other. This may have confounded results as cam- LC were likely due to participants deviating from the dem- era holding performance may have increased by partaking onstrated methods as they may have attempted to take short- in the skills course and the participants own laparoscopic cuts, felt rushed, or experimented with techniques. This was skills may have increased from holding the camera. This rectified through terminal feedback where reminders of the is extremely unlikely given that camera holding and lapa- most efficient techniques were restated. To pre-empt these roscopy utilize different skills. To our knowledge, no study plateaus there may be benefit in scheduling demonstrations identifies a crossover in performance between camera hold- after the initial phase of the LC to consolidate proper tech- ing and laparoscopic. Any potential bias was decisively nique and prevent this deviation. As barriers to skill acqui- addressed as all HCAs were at a proficient level of skill prior sition were identified the implantation of technology such to the collection results. Potential gains in skill from lapa- as the RCH may be used to overcome these challenges and roscopic exposure would have had limited impact to camera significantly reduce the learning curve, maximising the cost holding ability. Furthermore, the control group creates the efficiency and performance of the workforce. conventional environment where an inexperienced assistant This trial observed that the RCH reduces learning curves often holds the laparoscope [13]. in simulation of basic tasks. As BLS training programmes Another limitation was the workload experienced by have transferability to clinical practice it is plausible that the assistant was not measured. It is likely a greater differ- the RCH may be able to improve the performance of train- ence would have been observed as the primary benefit of ees by shortening the intra-operative LC. Benefit may also the RCH is to improve upon ergonomics of camera holding. be extended to experienced surgeons as changes to surgical An improvement to the trial would have been to also assess workload are more pronounced in clinical environments due performance using an experienced camera assistant [16]. 13 4190 Surgical Endoscopy (2021) 35:4183–4191 Conclusion 2. Aggarwal R et al (2009) Development of a virtual reality train- ing curriculum for laparoscopic cholecystectomy. Br J Surg 96(9):1086–1093 This study identifies that a RCH significantly benefits nov- 3. Brunckhorst O et al (2016) Training, simulation, the learning ices in BLS particularly when camera movement is mini- curve, and how to reduce complications in urology. Eur Urol mal. As these results were from a low-fidelity environment Focus 2(1):10–18 4. Akdemir A et al (2014) Effect of spaced training with a box future randomized controlled trials should consider per- trainer on the acquisition and retention of basic laparoscopic formance of intermediates and experts in clinical settings skills. Int J Gynaecol Obstet 127(3):309–313 where prolonged operations may emphasize the benefits of 5. Ali JM, Lam K, Coonar AS (2018) Robotic camera assistance: RCHs [5] [16, 24]. Additional workload scores and intra- the future of laparoscopic and thoracoscopic surgery? Surg Innov 25(5):485–491 operative ergonomic studies may produce more reliable 6. Angell J et al (2013) Contribution of laparoscopic training to results of the FreeHand’s benefit as different stressors are robotic proficiency. J Endourol 27(8):1027–1031 prevalent during surgery [28]. 7. 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Amin, Nurhan Abbud, Abdullatif Aydin, colon surgery. J Laparoendosc Adv Surg Tech A 14(6):345–348 Ben Van Cleynenbreugel, Domenico Veneziano, Bhaskar Somani, Ali 13. Veneziano D et al (2016) Construct, content and face validity Serdar Gözen, Juan Palou Redorta, Muhammad S. Khan, Prokar Das- of the camera handling trainer (CHT): a new E-BLUS training gupta, Jonathan Makanjuoala, and Kamran Ahmed have no conflicts task for 30 degrees laparoscope navigation skills. World J Urol of interest or financial ties to disclose. 34(4):479–484 14. Jaspers JE et al (2004) Camera and instrument holders and their Ethical approval Ethical approval was granted by the KCL BDM clinical value in minimally invasive surgery. Surg Laparosc research ethics subcommittee. Participants were required to give writ- Endosc Percutan Tech 14(3):145–152 ten and verbal consent for use of their anonymized data. 15. 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Amin1 · Abdullatif Aydin1 · Nurhan Abbud1 · Ben Van Cleynenbreugel2,9 · Domenico Veneziano3,9 · Bhaskar Somani4,9 · Ali Serdar Gözen5,9 · Juan Palou Redorta6,9 · M. Shamim Khan1,7 · Prokar Dasgupta1,7 · Jonathan Makanjuoala8 · Kamran Ahmed1,8,9 1 Mohammad S. A. Amin MRC Centre for Transplantation, King’s College London, mohammad.amin@kcl.ac.uk Guy’s Hospital, King’s Health Partners, London SE1 9RT, UK Abdullatif Aydin 2 abdullatif.aydin@kcl.ac.uk Department of Urology, University Leuven, Leuven, Belgium 3 Nurhan Abbud Department of Urology and Renal Transplantation, nurhan.a@hotmail.co.uk Bianchi-Melacrino-Morelli Hospital, Reggio Calabria, Italy 4 Ben Van Cleynenbreugel Department of Urology, Southampton University Hospital ben.vancleynenbreugel@uzleuven.be NHS Foundation Trust, Southampton, UK 5 Domenico Veneziano Department of Urology, SLK‑Kliniken, University Info@domenicoveneziano.it of Heidelberg, Heilbronn, Germany 6 Bhaskar Somani Department of Urology, Fundació Puigvert, Universitat bhaskarsomani@yahoo.com Autònoma de Barcelona, Barcelona, Spain 7 Ali Serdar Gözen Urology Centre, Guy’s and St. Thomas’ NHS Foundation asgozen@yahoo.com Trust, London, UK 8 Juan Palou Redorta Department of Urology, King’s College Hospital NHS jpalou@fundacio‑puigvert.es Foundation Trust, London, UK 9 M. Shamim Khan European School of Urology (ESU) Training and Research shamim.khan@gstt.nhs.uk Group, Barcelona, Spain Prokar Dasgupta prokar.dagsupta@kcl.ac.uk Jonathan Makanjuoala jonathan.makanjuola@nhs.net 13