Ahead of the Curve: Tracking Progress in Novice Microsurgeons.

BACKGROUND: The purpose of this study was to evaluate learning curves for an existing microsurgical training model. We compared efficiency and amount of training needed to achieve proficiency between novice microsurgeons without operative experience versus those who had completed a surgical internship. METHODS: Ten novice microsurgeons anastomosed a silastic tube model. Time to perform each anastomosis, luminal diameter, and number of errors were recorded. RESULTS: First year residents improved up to a brief plateau at 10 repetitions, followed by continued improvement. Second year residents improved up to a plateau at 10 repetitions with no further improvement thereafter. There was no significant difference in luminal area or errors between groups. CONCLUSION: Residents with no operative experience can benefit from early exposure to microsurgical training. These interns continue to improve with additional repetitions while second year residents achieve proficiency with fewer repetitions.

Evaluation of AlloMax acellular dermal matrix for objective collagen deposition.

Acellular dermal matrix products are popular in various aspects of surgical reconstruction including hernia repairs and breast reconstructions. The goal of this study was to determine quantitative collagen weights of AlloMax (C. R. Bard, Inc. [Davol], Warwick, RI) and of contralateral dermis for composition comparison. A rehydrated sample of AlloMax was subcutaneously implanted on the dorsum of 18 male Wistar rats. Rats were randomly assigned to groups on the basis of in vivo implant time: 1, 3, and 6 weeks. At the end of the implant time, the AlloMax was removed and a section of contralateral dermis was excised as a control. Hydroxyproline, rat Collagen I and Collagen III, and neoangiogenesis were determined in the sections. The results are reported as mean ± standard error of the mean. Analysis of variance was used to evaluate the between-group differences. A p value of 0.05 or less was considered significant. Hydroxyproline was significantly increased in the 6-week AlloMax implant (26.19 ± 1.05 vs. 15.03 ± 3.29). Collagen I and Collagen III were significantly increased following 3 weeks in vivo (612.5% ± 98.0 vs. 312.9% ± 82.7, p < 0.05 Collagen I). Neoangiogenesis was significantly increased at 3 and 6 weeks in vivo (2.3 ± 0.3 and 1.9 ± 0.3). Acellular AlloMax was rapidly incorporated into the rat dorsum. The measurement parameters were greater than or equivalent to contralateral dermis in this study.

Pneumomediastinum following hyperbaric oxygen therapy for carbon monoxide poisoning: case report.

A 5-year-old boy trapped in a house fire was transported to the emergency department, unconscious with suspected carbon monoxide poisoning. The patient underwent a difficult intubation, but did not initially demonstrate any radiographic abnormalities. The patient remained intubated and underwent hyperbaric oxygen therapy using the carbon monoxide treatment protocol. Immediate post-therapy chest radiograph revealed the development of occult pneumomediastinum. The patient remained stable on positive-pressure ventilation and the pneumomediastinum resolved spontaneously. The patient was extubated on post-injury Day #2 and was discharged post-injury Day #4 with no residual clinical sequelae. The development of pneumomediastinum associated with hyperbaric oxygen therapy for carbon monoxide poisoning appears to be a rare phenomenon. However, clinicians should be aware of the risk factors that predispose patients to developing pneumomediastinum and have a low threshold for obtaining routine pre- and post-procedure screening chest radiographs in intubated and critically ill patients, particularly in children.

Objective evaluation of skill acquisition in novice microsurgeons.

INTRODUCTION: Medical training is increasingly focused on patient safety, limiting the ability to practice technical skills in the operative arena. Alternative methods of training residents must be designed and implemented. METHODS: Three expert microsurgeons were solicited to develop two drills to help residents acquire the basic subset of skills in microsurgery. The first drill was performance of five consecutive simple interrupted sutures on a rubber glove. Expert proficiency was considered a drill time of two standard deviations from expert mean. The drill was performed up to 10 times until completion of the task at expert proficiency. The second drill was performance of an anastomosis on silastic tubing. Residents performed the drill sequentially until performing two consecutive drills at expert proficiency. RESULTS: Eight residents with no microsurgical experience volunteered. Six of the eight residents were able to perform the rubber glove drill at expert proficiency within 10 attempts, with an average of 5.3. All of the residents were able to perform two consecutive silastic tubing drills at expert proficiency within nine attempts, with an average of 5.4. CONCLUSION: Residents were able to acquire a basic subset of microsurgical skills within a reasonable time period using these drills.

Reducing Complications and Expanding Use of Robotic Rectus Abdominis Muscle Harvest for Pelvic Reconstruction.

SUMMARY: The rectus abdominis flap has long been a workhorse in perineal reconstruction. Although traditionally approached though an external incision, the morbid nature of the incision and subsequent violation of the anterior rectus sheath has encouraged innovation of minimally invasive approaches for harvest. In this study, we present our experience, evolution, and comparative outcomes of robotic rectus abdominis muscle harvest. A retrospective review of perineal reconstruction was performed for a 6-year period (2014 to 2019). Robotic rectus abdominis muscle flaps were compared to nonrobotic techniques performed during this time. Descriptive statistics and complication profiles were computed. The details of our surgical technique are also described. Thirty-six patients underwent perineal reconstruction. Sixteen were performed using the robotic rectus abdominis muscle and 20 with traditional repairs (12 vertical rectus abdominis myocutaneous flaps and eight gracilis flaps). Demographic profiles were similar between cohorts, including age, body mass index, smoking, diabetes, neoadjuvant radiation therapy, and need for vaginal wall repair. Six robotic patients underwent abdominal wall reinforcement with biological mesh. Length of stay, surgical times, and incidence of major complications were similar between cohorts with a trend toward increased minor complications in traditional reconstructions (55 percent versus 31 percent; p = 0.15). Robotic rectus abdominis muscle harvest is a powerful tool that continues to evolve the potential to mitigate common morbidities and complications of traditional repair and further enhance cosmetic outcomes. This study suggests that greater flexibility for reconstruction can be afforded with harvest of the posterior rectus sheath and complications avoided with prophylactic mesh reinforcement. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

Closing the Gap Between Mammalian and Invertebrate Peripheral Nerve Injury: Protocol for a Novel Nerve Repair.

BACKGROUND: Outcomes after peripheral nerve injuries are poor despite current nerve repair techniques. Currently, there is no conclusive evidence that mammalian axons are capable of spontaneous fusion after transection. Notably, certain invertebrate species are able to auto-fuse after transection. Although mammalian axonal auto-fusion has not been observed experimentally, no mammalian study to date has demonstrated regenerating axolemmal membranes contacting intact distal segment axolemmal membranes to determine whether mammalian peripheral nerve axons have the intrinsic mechanisms necessary to auto-fuse after transection. OBJECTIVE: This study aims to assess fusion competence between regenerating axons and intact distal segment axons by enhancing axon regeneration, delaying Wallerian degeneration, limiting the immune response, and preventing myelin obstruction. METHODS: This study will use a rat sciatic nerve model to evaluate the effects of a novel peripheral nerve repair protocol on behavioral, electrophysiologic, and morphologic parameters. This protocol consists of a variety of preoperative, intraoperative, and postoperative interventions. Fusion will be assessed with electrophysiological conduction of action potentials across the repaired transection site. Axon-axon contact will be assessed with transmission electron microscopy. Behavioral recovery will be analyzed with the sciatic functional index. A total of 36 rats will be used for this study. The experimental group will use 24 rats and the negative control group will use 12 rats. For both the experimental and negative control groups, there will be both a behavior group and another group that will undergo electrophysiological and morphological analysis. The primary end point will be the presence or absence of action potentials across the lesion site. Secondary end points will include behavioral recovery with the sciatic functional index and morphological analysis of axon-axon contact between regenerating axons and intact distal segment axons. RESULTS: The author is in the process of grant funding and institutional review board approval as of March 2020. The final follow-up will be completed by December 2021. CONCLUSIONS: In this study, the efficacy of the proposed novel peripheral nerve repair protocol will be evaluated using behavioral and electrophysiologic parameters. The author believes this study will provide information regarding whether spontaneous axon fusion is possible in mammals under the proper conditions. This information could potentially be translated to clinical trials if successful to improve outcomes after peripheral nerve injury. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/18706.