Abdominal Wall Movements Predict Intra-Abdominal Pressure Changes in Rats: A Novel Non-Invasive Intra-Abdominal Pressure Detection Method.

(1) Background: As increases in intra-abdominal pressure (IAP) result in irreversible tissue damage, monitoring IAP in critically ill patients using the common urinary bladder catheter method is essential. However, this method can result in complications and is not suitable for very low birth weight neonates. The aim of this study was to establish a non-invasive and accurate method to detect IAP changes using an animal model. (2) Methods: IAP changes via intra-abdominal air application (up to 20 mmHg) were measured in 19 Wistar rats via an intra-abdominally placed intracranial pressure probe. Concurrently, abdominal surface tension was measured using a Graseby capsule (GC). (3) Results: A high correlation between abdominal wall distension and IAP (r = 0.9264, CI 0.9249-0.9279) was found for all subjects. (4) Conclusions: IAP changes in rats can be detected non-invasively using a GC. However, further studies are necessary to assess whether IAP changes can be measured using a GC in the neonatal population.

The Spaced Learning Concept in Combination With Halsted and Peyton - A Randomized Controlled Study.

BACKGROUND: Several motor learning models have been used to teach highly complex procedural skills in medical education. Two approaches are often employed amongst health care professionals: Halsted's "See one - do one - teach one" concept and Peyton's Four-step approach. Peyton's deconstruction of the learning process into 4 sub-steps was reported to be preferable for learning/acquiring/teaching complex clinical skills. However, a new increasingly popular technique is known as the spaced learning method. In a previous study, we were able to confirm that the spaced learning concept is superior for laparoscopic suturing and knot tying compared to conventional training curricula, this current study aimed to assess the influence of spaced learning in combination with Halsted's and Peyton's tutoring approaches on laparoscopic knot tying of medical students. METHODS: After randomization, 20 medical students were either assigned to Halsted's or Peyton's teaching approach and trained one-on-one (teacher-student). Additionally, all subjects were trained according to the spaced learning concept, containing 40 minutes of content-blocks, followed by a 20-minute break involving coordinated, standardized physical activity. This was repeated three times. Primary endpoints were time, knot quality, precision, knot strength, as well as overall laparoscopic knotting performance and competency. To evaluate the motivation of the subjects, an 18-item questionnaire was utilized to measure four motivational factors (anxiety, probability of success, interest, and challenge). RESULTS: All trainees significantly improved after training in all knot attributes. Trainees assigned to Halsted's method were able to significantly outperform the Peyton group in knot quantity within 30 minutes (p = 0.013), time/knot (p = 0.033), performance score (p = 0.009), and precision (p = 0.032). No significant difference between Halsted and Peyton was found for knot strength and quality. Furthermore, no significant difference was identified comparing motivation pre- and post-training. However, subjects in the Peyton appeared to be significantly more anxious after training. CONCLUSION: Combining spaced learning technique with Halsted's "see one - do one - teach one" appears to be superior to Peyton's Four-step approach in conjunction with spaced learning in surgical naïve students. We recommend further studies evaluating the combination of spaced learning with Halsted and Peyton's instructional methods.

The Length of the Transition Zone in Patients with Rectosigmoid Hirschsprung Disease.

Background: The transition zone (TZ) is defined by specific histological findings in patients with Hirschsprung Disease (HSCR). HSCR treatment includes surgical removal of the aganglionic zone (AZ). During the pull-through procedure, it is critical to resect the TZ. Given the TZ's wide histological heterogeneity, we wanted to know how extensive the histological transition zone is. Methods: A retrospective study of patients who had pull-through surgery for rectosigmoid HSCR between January 2010 and December 2020 was carried out. Demographics, length of TZ and AZ, age and symptoms upon presentation, and complications after surgery were also obtained. Results: The inclusion criteria were met by 50 patients. The mean age of all patients was 10 months (0.1-107.5 months), with a mean age at pull-through of 16.3 months (3-112 months). Thirty-one out of fifty patients (62%) received primary laparoscopic endorectal pull-through surgery (LEPT). The average TZ length of all patients was 2.6 cm (0-10 cm), and the AZ length was 9.6 cm (1-30 cm). The length of the AZ and TZ were shown to have no correlation (r² = 0.237). Conclusions: The current study found that the mean length of the TZ in individuals with rectosigmoid HSCR is less than 5 cm in most cases and has no correlation with the length of the AZ.

The Spaced Learning Concept Significantly Improves Acquisition of Laparoscopic Suturing Skills in Students and Residents: A Randomized Control Trial.

INTRODUCTION: Spaced learning consists of blocks with highly condensed content that interrupted by breaks during which distractor activities, such as physical activity, are performed. The concept has been shown to be superior in complex motor skill acquisition like laparoscopic suturing and knot tying. Preliminary studies have solely been conducted with medical students. Therefore, it remained unanswered if the spaced learning concept would also work for pediatric surgery residents. MATERIALS AND METHODS: The study aimed to evaluate the effectiveness of spaced learning, students, and residents were asked to perform four surgeons' square knots on a bowel model within 30 minutes prior and post 3 hours of hands-on training. To examine the long-term skills, the same subjects were asked to perform a comparable, but more complex task 12 months later without receiving training in the meantime. Total time, knot stability, suture accuracy, knot quality, and laparoscopic performance were assessed. Additionally, motivation was accessed by using the questionnaire on current motivation. Differences were calculated using mixed analysis of variance, Mann-Whitney U test, and multivariate analysis of covariance. RESULTS: A total of 20 medical students and 14 residents participated in the study. After randomization, 18 were trained using the spaced learning concept and 16 via conventional methods. Both groups had comparable baseline characteristics and improved significantly after training in all assessed measures. The spaced learning concept improved procedure performance as well as knot quality and stability in both students and residents. However, residents that trained via spaced learning showed significantly better long-term results regarding knot quality and speed in comparison to students. Although anxiety was significantly reduced in both training groups over time, residents were significantly more interested regarding knot tying than students. CONCLUSION: This study dispels any remaining doubt that the spaced learning concept might only work for medical students. It appears that the spaced learning concept is very suitable for residents in acquiring complex motor skills. It is superior to conventional training, resulting in improved procedural performance as well as knot quality and speed. Hence, tailored training programs should not only be integrated early on in students' curricula but also in surgical training programs.

Classical but Not Rap Music Significantly Improves Transferability and Long-Term Acquisition of Laparoscopic Suturing Skills: A Randomized Controlled Trial.

INTRODUCTION: Acoustic distractions have been shown to increase the level of stress and workload in the operating room (OR). Noise significantly reduces surgical performance, but experienced surgeons are able to reduce the acoustic perception of their surroundings to maintain a high level of performance in complex surgical tasks. However, music has been shown to improve learning and performance of complex motor skills. The aim of this study was to evaluate the influence of music on transferability and long-term acquisition of laparoscopic suturing skills. MATERIALS AND METHODS: To evaluate the effects of music on training, subjects were asked to perform four surgeon's square knots on a bowel model within 30 minutes-prior and post 3 hours of hands-on training. To examine long-term skills, the same students were asked to perform a comparable, but more complex, task (four slip knots in a model of esophageal atresia) 6 months post initial training, as a follow-up measurement. Total time, knot stability (evaluated via tensiometer), suture accuracy, knot quality (Muresan scale), and laparoscopic performance (Munz checklist) were assessed. RESULTS: Twenty-four students were included in the study; after simple randomization, 16 were trained while exposed to music (eight to Bach and eight to Bushido) and eight with traditional methods. Seven were lost due to follow-up. Both groups had comparable baseline characteristics and significantly improved after training, in all parameters assessed in this study. Subjects that trained with classical music were superior in terms of speed (p = 0.006), knot quality (p = 0.014), and procedural performance (p = 0.034) compared with controls. CONCLUSION: Music during acquisition of complex motor skills, like laparoscopic suturing and knot tying, is superior to traditional training. Especially music considered nondisturbing significantly improved speed, knot quality, and performance. Thus, incorporation of pleasant music into surgical skills training and the OR should be considered.

Spaced Education Improves the Retention of Laparoscopic Suturing Skills: A Randomized Controlled Study.

INTRODUCTION: Spaced learning has been shown to be superior in complex motor skill acquisition like laparoscopic suturing and knot tying. By using a pre-post follow-up design, the aim of the study was to evaluate the long-term impact of implementation of the spaced learning concept in laparoscopic training. MATERIALS AND METHODS: To evaluate the effectiveness of spaced learning, subjects were asked to perform four surgeon's square knots on a bowel model within 30 minutes-prior and after 3 hours of hands-on training. To examine the long-term skills, the same students were asked to perform a comparable, but more complex, task (four slip knots in a model of esophageal atresia) 12 months later as follow-up measurement. Total time, knot stability (evaluated via tensiometer), suture accuracy, knot quality (Muresan scale), and laparoscopic performance (Munz checklist) were assessed. Moreover, motivation was accessed using Questionnaire on Current Motivation. RESULTS: Twenty students were included in the study; after simple randomization, 10 were trained using the "spaced learning" concept and 10 via traditional methods. Both groups had comparable baseline characteristics and improved after training significantly, regarding all aspects assessed in this study. Subjects that trained via spaced learning were superior in terms of speed (p = 0.021), knot quality (p = 0.008), and suture strength (p = 0.003). Additionally, spaced learning significantly decreased anxiety (p = 0.029) and probability of success (p = 0.005). CONCLUSION: The spaced learning concept is very suitable for long-term complex motor skill acquisition, like laparoscopic suturing and knot tying. It is superior to conventional training regarding speed and, most importantly, knot quality and stability, resulting in improved confidence and motivation. Thus, we strongly recommend to incorporate the spaced learning concept into training courses and surgical programs.

The spaced learning concept significantly improves training for laparoscopic suturing: a pilot randomized controlled study.

BACKGROUND: Spaced learning has been shown to be effective in various areas like traditional knowledge or motor skill acquisition. To evaluate the impact of implementation of the spaced learning concept in laparoscopic training was the aim of this study. METHODS: To evaluate the effectiveness of spaced learning, subjects were asked to perform four surgeon's square knots on a bowel model prior and post 3 h of hands-on training. All subjects were medical students and novice in laparoscopic suturing. Total time, knot stability (evaluated via tensiometer), suture accuracy, knot quality (Muresan score), and laparoscopic performance (Munz checklist) were assessed. Moreover, motivation was accessed using Questionnaire on Current Motivation. RESULTS: Twenty students were included in the study; after simple randomization, ten were trained using "spaced learning" concept and ten conservatively. Both groups had comparable baseline characteristics and improved after training significantly regarding all aspects assessed in this study. Subjects that trained via spaced learning were superior in terms of suture performance, knot quality, and suture strength. Ultimately, spaced learning significantly decreased anxiety and impression of challenge compared to controls. CONCLUSION: The spaced learning concept is very suitable for complex motor skill acquisition like laparoscopic suturing and knot tying. It significantly improves laparoscopic performance and knot quality as shown by the knot score and suture strength. Thus, we recommend to incorporate spaced learning into training courses and surgical programs.

Therapeutic targeting of extracellular DNA improves the outcome of intestinal ischemic reperfusion injury in neonatal rats.

Thrombosis and inflammation cooperate in the development of intestinal infarction. Recent studies suggest that extracellular DNA released by damaged cells or neutrophils in form of extracellular traps (NETs) contributes to organ damage in experimental models of ischemia-reperfusion injury. Here we compared the therapeutic effects of targeting fibrin or extracellular DNA in intestinal infarction after midgut volvulus in rats. Following iatrogenic midgut volvulus induction for 3 hours, we treated animals with a combination of tissue plasminogen activator (tPA) and low molecular weight heparin (LMWH) to target fibrin or with DNase1 to degrade extracellular DNA. The therapeutic effects of tPA/LMWH and DNase1 were analyzed after 7 days. We observed that both therapeutic interventions ameliorated tissue injury, apoptosis, and oxidative stress in the intestine. DNase1, but not tPA/LMWH, reduced intestinal neutrophil infiltration and histone-myeloperoxidase-complexes, a surrogate marker of NETs, in circulation. Importantly, tPA/LMWH, but not DNase1, interfered with hemostasis as evidenced by a prolonged tail bleeding time. In conclusion, our data suggest that the therapeutic targeting of fibrin and extracellular DNA improves the outcome of midgut volvulus in rats. DNase1 therapy reduces the inflammatory response including NETs without increasing the risk of bleeding. Thus, targeting of extracellular DNA may provide a safe therapy for patients with intestinal infarction in future.

Degradation of Extracellular DNA by DNase1 Significantly Reduces Testicular Damage After Testicular Torsion in Rats.

OBJECTIVE: To examine the effects of DNase1 treatment on testicular damage after testicular torsion (TT). It has been demonstrated that TT induces thrombus formation and that anticoagulation significantly reduces testicular damage after TT. It was hypothesized that these thrombi are dependent on neutrophil extracellular traps (NETs) and thus NETs disintegration would reduce testicular cell damage. METHODS: A sham operation was performed in 10 rats. Thirty-four rats underwent induction of iatrogenic TT for 3 hours. After de-torsion and randomization, 24 rats received DNase1 or inactivated DNase1. The following parameters were assessed: testicular damage via Cosentino grading; spermatogenesis via Johnsen score; stem cell factor and c-Kit, apoptosis via Bax, Bcl2, Terminal deoxynucleotidyl transferase (TdT) dUTP Nick-End Labeling assay, and cleaved caspase3 staining; oxidative stress via superoxide dismutase, catalase, glutathione peroxidase, and malondialdehyde; neutrophil recruitment via myeloperoxidase and neutrophil elastase staining; and NET formation via cell-free DNA. RESULTS: Forty-three rats were included in the study. Subjects treated with DNase1 showed significantly less cellular damage, oxidative stress, and apoptosis. Further, DNase1-treated rats demonstrated a significant improvement of spermatogenesis, compared with the controls. CONCLUSION: The results of the study indicate that thrombus formation during TT is quite likely NET associated, and that dissolution of cell-free DNA (including NETs) significantly improves testicular damage in rats. As treatment with DNase1 reduced apoptosis, oxidative stress, and inflammation, without adversely affecting coagulation, it might be a suitable treatment for (neonatal) TT and ought to be evaluated in humans.

Training Significantly Improves Fetoscopy Performance: A Pilot Randomized Controlled Trial.

Background Implementation of complex fetoscopic procedures that included intracorporeal suturing has been limited due to technical difficulties that might be surmounted with adequate training. Evaluating the impact of laparoscopic or fetoscopic training on fetoscopic performance was the aim of this study. Methods To evaluate fetoscopic performance after either laparoscopic or fetoscopic training, subjects were asked to perform four surgeon's square knots fetoscopically prior and post 2 hours of hands-on training. All subjects were medical students and novice in laparoscopic and fetoscopic interventions. Total time, knot stability (evaluated via tensiometer), suture accuracy, knot quality, and fetoscopic performance were assessed. Results Forty-six subjects were included in the study; after simple randomization, 24 were trained fetoscopically and 22 laparoscopically. Both groups had comparable baseline characteristics and improved after training significantly regarding all aspects assessed in this study. Subjects who trained fetoscopically were superior in terms of suturing and knot-tying performance. Conclusion Training significantly improves fetoscopic performance and may indeed be the keystone for future complex fetoscopic interventions. It seems advisable to train rather fetoscopically than laparoscopically resulting in higher suture and knot-tying quality.