Innovating medical education: Development of an affordable, 3-D printed knot-tying simulator

BACKGROUND

Three-dimensional (3-D) printing offers an innovative option to produce clinical simulators because of its low production costs and widespread availability. We aimed to develop a low-cost, 3-D printed knot-tying simulator that overcomes the barriers students face in self-directed skills development.

APPROACH

Medical students completing a procedural residency preparation course (PRPC) completed a pre-survey with Likert scales and multiple choice questions to assess their perceptions of and barriers to self-directed knot-tying practice. Subsequently, a 3-D printed knot-tying simulator, which contains a progression of knot-tying challenges and a designated video curriculum, was designed. After utilising the simulator in a 1-hour, faculty-guided knot-tying session, PRPC students assessed the educational utility and usability of the simulator via a post-survey.

EVALUATION

The primary barriers students faced in engaging in self-directed knot-tying practice included limited accessibility to simulators and insufficient knowledge of knot-tying techniques. Many students (91.3%, n = 21) agreed that practicing with the simulator improved their knot-tying motor skills and was easy to use (100%, n = 23). Twenty-two (95.7%) students agreed that they would continue to use the simulator beyond the knot-tying session and PRPC.

IMPLICATIONS

We demonstrate the educational utility and usability of a novel 3-D printed knot-tying simulator for medical education. Enabling students to engage in self-directed technical skills development is critical in developing surgical skills that can translate to clinical environments. Our simulator highlights the benefits of 3-D printers as an innovative, inexpensive option to improve the availability and accessibility to medical education tools.

Nodo-Tie: an innovative, 3-D printed simulator for surgical knot-tying skills development

Introduction

Clinical simulators are an important resource for medical students seeking to improve their fundamental surgical skills. Three-dimensional (3-D) printing offers an innovative method to create simulators due to its low production costs and reliable printing fidelity. We aimed to validate a 3-D printed knot-tying simulator named Nodo-Tie.

Methods

We designed a 3-D printed knot-tying simulator integrated with a series of knot-tying challenges and a designated video curriculum made accessible via a quick-response (QR) code. The Nodo-Tie, which costs less than $1 to print and assemble, was distributed to second-year medical students starting their surgical clerkship. Participants were asked to complete a survey gauging the simulator's usability and educational utility. The time between simulator distribution and survey completion was eight weeks.

Results

Students perceived the Nodo-Tie as easy-to-use (4.6 ± 0.8) and agreed it increased both their motor skills (4.5 ± 0.9) and confidence (4.5 ± 0.8) for tying surgical knots in the clinical setting. Many students agreed the Nodo-Tie provided a stable, durable surface for knot-tying practice (83.7%, n = 41) and that they would continue to use it beyond their participation in the study period (91.7%, n = 44).

Discussion

Medical students found this interactive, 3-D printed knot-tying simulator to be an effective tool to use for self-directed development of their knot-tying skills. Given the Nodo-Tie's low cost, students were able to keep the Nodo-Tie for use beyond the study period. This increases the opportunity for students to engage in the longitudinal practice necessary to master knot-tying as they progress through their medical education.

Key messages

Clinical simulators provide proactive learners with reliable, stress-free environments to engage in self-directed surgical skills development. The Nodo-Tie, a 3-D printed simulator, serves as a cost-effective, interactive tool for medical students to develop their knot-tying abilities beyond the clinical setting.

The incidence and natural history of ascites after liver transplantation

BACKGROUND

Ascites is common in cirrhosis but uncommon after liver transplant. We aimed to characterize the incidence, natural history, and current management strategies of post-transplant ascites.

METHODS

We performed a retrospective cohort study of patients who underwent liver transplantation at 2 centers. We included patients who underwent deceased donor whole graft liver transplants between 2002 and 2019. Chart review identified patients with post-transplant ascites, requiring a paracentesis between 1 and 6-month post-transplants. Detailed chart review identified clinical and transplant characteristics, evaluation of ascites etiology, and treatments.

RESULTS

Of 1591 patients who successfully underwent a first-time orthotopic liver transplant for chronic liver disease, 101 (6.3%) developed post-transplant ascites. Only 62% of these patients required large volume paracentesis for ascites before transplant. 36% of patients with post-transplant ascites had early allograft dysfunction. Most patients with post-transplant ascites (73%) required a paracentesis within 2 months of transplant, but 27% had delayed ascites onset. From 2002 to 2019, ascites studies were obtained less often, and hepatic vein pressure measurement was performed more often. Diuretics were the mainstay of treatment (58%). The use of albumin infusion and splenic artery embolization to treat post-transplant ascites increased over time. Larger pre-transplant spleen size was associated with a greater number of post-transplant paracenteses (r=0.32 and p=0.003). For patients who underwent splenic intervention, paracentesis frequency was significantly reduced (1.6-0.4 paracenteses/month, p=0.0001). The majority (72%) of patients had clinical resolution of their ascites at 6-month post-transplant.

CONCLUSIONS

Persistent or recurrent ascites continues to be a clinical issue in the modern era of liver transplantation. Most had clinical resolution within 6 months, some requiring intervention.

How I Do It: Pilot Study of Video-Based Feedback as an Educational Tool for Medical Students' Presentations on Morning Rounds

OBJECTIVE

Morning rounds are a bedrock learning opportunity during clinical rotations in medical school. Specific feedback is critical for students to improve presentation skills and build confidence, however, current feedback mechanisms are fragmented and nonstandard. We aimed to assess whether video-based coaching of morning rounds could improve student feedback and self-awareness without increasing anxiety during patient presentations.

DESIGN

Medical students during core clinical clerkships were filmed presenting on morning rounds during their surgery clerkship. A designated faculty coach reviewed the video prior to an in-person coaching session. Students reviewed the video with faculty and were coached on content, presentation style, and presence. A short survey assessed students' pre- and postcoaching confidence, skill, and the utility of the coaching session.

SETTING

University of Michigan Health System, Department of Surgery, Division of General Surgery, Ann Arbor, Michigan PARTICIPANTS: Eight medical student volunteers during their core clinical clerkships at University of Michigan Medical School during the surgery clerkship.

RESULTS

Comparison of pre- and post self-assessments showed that students underestimated their knowledge of basic and clinical science and overestimated their clinical assessment skills and ability to appropriately address the core components of a presentation. Most students (75%) did not think that the filming process altered their performance and only 25% of students felt increased anxiety due to filming. All students agreed that the feedback session was useful and helped them understand how to improve their oral presentations.

CONCLUSION

This pilot demonstrates the feasibility and value of video-based coaching as an educational tool for medical students on clerkships. A larger sample size is needed to further evaluate the effectiveness of video-based coaching in establishing baseline clinical abilities and identifying potential areas for improvement.

Wandering spleen leading to splenic torsion with gastric and pancreatic volvulus

This case highlights a 37-year-old woman with primary sclerosing cholangitis awaiting liver transplantation who presented with torsion of a wandering spleen with associated gastric and pancreatic volvulus. The patient underwent emergent exploratory laparotomy with splenectomy. She had an uncomplicated postoperative course and recovered well.

Portal vein thrombosis and outcomes for pediatric liver transplant candidates and recipients in the United States

The effect of occlusive portal vein thrombosis (PVT) on the mortality of pediatric liver transplant candidates and recipients is poorly defined. Using standard multivariate techniques, we studied the relationship between PVT and waiting-list and posttransplant survival rates with data from the Scientific Registry of Transplant Recipients (September 2001 to December 2007). In all, 5087 liver transplant candidates and 3630 liver transplant recipients were evaluated during the period. PVT was found in 1.4% of the liver transplant candidates (n = 70) and in 3.7% of the liver transplant recipients (n = 136). PVT was not associated with increased wait-list mortality [hazard ratio (HR) = 1.1, 95% confidence interval (CI) = 0.5-2.4, P = 0.77]. Conversely, PVT patients had a significantly lower unadjusted survival rate in the posttransplant period (P = 0.01). PVT was independently associated with increased posttransplant mortality in multivariate models (30-day survival: HR = 2.9, 95% CI = 1.6-5.3, P = 0.001; overall survival: HR = 1.7, 95% CI = 1.1-2.4, P = 0.01). The presence of PVT in pediatric liver candidates was not associated with increased wait-list mortality but was clearly associated with posttransplant mortality, especially in the immediate postoperative period.