Laparoscopic versus open inguinal hernia repair in children ≤3: a randomized controlled trial.

PURPOSE: Laparoscopy is being increasingly applied to pediatric inguinal hernia repair. In younger children, however, open repair remains preferred due to concerns related to anesthesia and technical challenges. We sought to assess outcomes after laparoscopic and open inguinal hernia repair in children less than or equal to 3 years. METHODS: A prospective, single-blind, parallel group randomized controlled trial was conducted at three clinical sites. Children ≤3 years of age with reducible unilateral or bilateral inguinal hernias were randomized to laparoscopic herniorrhaphy (LH) or open herniorrhaphy (OH). The primary outcome was the number of acetaminophen doses. Secondary outcomes included operative time, complications, and parent/caregiver satisfaction scores. RESULTS: Forty-one patients were randomized to unilateral OH (n = 10), unilateral LH (n = 17), bilateral OH (n = 5) and bilateral LH (n = 9). Acetaminophen doses, LOS, complications, and parent/caregiver scores did not differ among groups. Laparoscopic unilateral hernia repair demonstrated shorter operative time, a consistent finding for overall laparoscopic repair in univariate (p = 0.003) and multivariate (p = 0.010) analysis. No cases of testicular atrophy were documented at 2 (SD = 2.7) years. CONCLUSION: Children ≤3 years of age in our cohort safely underwent LH with similar pain scores, complications, and recurrence as OH. Parents and caregivers report high satisfaction with both techniques.

Practice patterns in high-risk bariatric venous thromboembolism prophylaxis.

BACKGROUND: In the morbidly obese population that undergoes bariatric surgery, venous thromboembolism (VTE) is the leading cause of morbidity and mortality. Certain factors place a patient at higher risk for VTE. No consensus exists on VTE screening or prophylaxis for the high-risk patient. This report describes the results of a survey on VTE screening and prophylaxis patterns in high-risk bariatric surgery. METHODS: Members of the Society of American Gastrointestinal and Endoscopic Surgeons (SAGES) were queried on factors that identified bariatric patients as high risk for VTE and on routine screening and prophylaxis practices. This included mechanical and chemical prophylaxis, duration of therapy, and use of inferior vena cava (IVC) filters. RESULTS: Of the 385 surgeons who responded to the survey, 81 % were bariatric surgeons, and the majority managed more than 50 cases annually. One or more of the following risk factors qualified patients as high risk: history of VTE, hypercoagulable status, body mass index (BMI) exceeding 55 kg/m(2), partial pressure of arterial oxygen (PaO(2)) lower than 60 mmHg, and severe immobility. Preoperative screening of patients for VTE was practiced routinely by 56 % of the surgeons, and 92.4 % used preoperative chemoprophylaxis. The most common agent used preoperatively was heparin (48 %), and Lovenox was most commonly used postoperatively (49 %). Whereas 48 % of the patients discontinued chemoprophylaxis at discharge, 43 % continued chemoprophylaxis as outpatients, and 47 % routinely screened for VTE postoperatively. Use of IVC filters was routine for 28 % of the patients, who most commonly removed them after 1-3 months. CONCLUSIONS: This study describes current practice patterns of VTE screening and prophylaxis in high-risk bariatric surgery. Nearly all surgeons agree on risk factors that qualify patients as high risk, but only half routinely screen patients preoperatively. Preoperative VTE chemoprophylaxis is used by nearly all surgeons, but the duration of therapy varies. Use of IVC filters is not routine, and postoperative screening was performed by less than half of the respondents. An understanding of current practice patterns yields insight into the rates of VTE and shows variability in the need for evidence-based prophylaxis and standardized screening.

Design of a mechanical clutch-based needle-insertion device.

Insertion of trocars, needles, and catheters into unintended tissues or tissue compartments results in hundreds of thousands of complications annually. Current methods for blood vessel cannulation or epidural, chest tube, and initial trocar placement often involve the blind pass of a needle through several layers of tissue and generally rely on distinguishable anatomic landmarks and a high degree of clinical skill. To address this simply and without the use of electronics, a purely mechanical clutch system was developed for use in medical devices that access tissue and tissue compartments. This clutch utilizes the surface contact of a buckled filament inside an S-shaped tube to transmit force from the filament (catheter/guide wire) to the tube (needle). Upon encountering sufficient resistance at the tip, such as dense tissue, the catheter buckles and locks within the tube, causing the filament and needle to advance as one. When the needle reaches the target tissue or fluid-filled cavity, the filament unlocks and slides freely into the target region while the needle remains stationary. A similar locking phenomenon has long been observed in drill strings inside drill shafts used by the oil-drilling industry, and oil industry models were adapted to describe the motion of this clutch system. A predictive analytical model was generated and validated with empirical data and used to develop prototypes of a complete device then tested in vitro on muscle tissue and in vivo on a porcine laparoscopic model with promising results.

Retrograde migration and endovascular retrieval of a venous bullet embolus.

Venous bullet embolism is a rare and complicated occurrence reported in approximately 0.3% of penetrating trauma. The management of bullet emboli is decided on a case-by-case basis, balancing the risk of the embolus itself against those associated with extraction. We report a case of a 19-year-old man who sustained a gunshot wound to the anterior chest, which migrated to the left internal iliac vein in a retrograde fashion. We were able to successfully retrieve the missile using an endovascular approach, thereby minimizing the morbidity associated with an open procedure.

Innovative approach to the difficult ventricular shunt using pleural access device for maintenance drainage: case report.

Patients with complex medical problems and multiple failed ventricular shunts require continued innovation for hydrocephalus management. The authors report the case of a 4-year-old boy with refractory hydrocephalus and secondary reduced ability to absorb CSF in both the pleural and peritoneal cavities following renal transplantation. A novel management approach was devised with split shunting to pleural and peritoneal targets as well as prophylactic pleural port placement to provide a method for minimally invasive thoracentesis should symptomatic pleural effusions develop. Fluid was successfully aspirated via the pleural port with relief of symptoms over a period of 16 months without complication. The authors demonstrate that a previously undescribed approach to distal shunting can prevent neurological sequelae of shunt failure and permit noninvasive maintenance drainage for patients in whom symptomatic pleural effusion is a recurrent complication.

Evaluation of Surgical Caseload Aboard the USNS COMFORT (T-AH 20) During Enduring Promise 2018.

The USNS COMFORT (T-AH-20) deployed in support of Enduring Promise 2018 (EP-18) for an 11-week humanitarian mission providing care to the residents of four host nations in Central and South America. The COMFORT provides the capability of providing medical, dental, and surgical care in humanitarian aid missions.

The promise of artificial liver replacement.

One of the most challenging clinical syndromes in medicine is that of acute liver failure (ALF). Many devices and systems have been devised to support ALF patients. This manuscript reviews the significant clinical findings of ALF, as well as, the non-biologic liver support systems and the bioartificial liver devices that have been clinically tested to support patients with this disease. Finally, we identify several improvements critical to the future of the field of bioartificial liver replacement therapy.

The Surgical Experience Aboard USNS COMFORT (T-AH-20) during Operation Continuing Promise 2015.

In 2015, the United States Navy hospital ship (USNS) COMFORT, deployed to 11 Caribbean and Latin American countries over a six-month period to provide humanitarian civic assistance. Personnel from the United States Navy and multiple nongovernmental organizations collaborated to offer surgical and medical care. Data from past deployments aid in planning for future missions by prioritizing finite resources and maximizing care. The data analyzed included all patients evaluated and treated by the Directorate of Surgical Services of the USNS COMFORT between April and September 2015. Comparative and descriptive statistics were performed to analyze patient demographics, surgical subspecialty performing the procedures, types of general and pediatric surgical procedures performed, operative times, and complication rates. Of the 1256 surgical cases performed aboard USNS COMFORT during CP15, 24.8 per cent were general surgery cases, followed by 16 per cent ophthalmology, 10.6 per cent pediatric surgery, 10 per cent plastic surgery, and eight additional specialties with <10 per cent of the cases each. Total operative time was 1253 hours with a total room time of 1896.5 hours. The identified complication rate was 1.99 per cent across all specialties. The USNS COMFORT platform offers the unique capability to provide humanitarian surgical assistance. Reporting these data demonstrate that there is a need for humanitarian assistance and this can be provided safely through the Continuing Promise mission. Future deployments may target resources toward the surgical services with higher volumes, which were general surgery, ophthalmology, pediatric surgery, and plastic surgery.

Mucous fistula refeeding decreases parenteral nutrition exposure in postsurgical premature neonates.

BACKGROUND/PURPOSE: Premature neonates can develop intraabdominal conditions requiring emergent bowel resection and enterostomy. Parenteral nutrition (PN) is often required, but results in cholestasis. Mucous fistula refeeding allows for functional restoration of continuity. We sought to determine the effect of refeeding on nutrition intake, PN dependence, and PN associated hepatotoxicity while evaluating the safety of this practice. METHODS: A retrospective review of neonates who underwent bowel resection and small bowel enterostomy with or without mucous fistula over 2years was undertaken. Patients who underwent mucous fistula refeeding (RF) were compared to those who did not (OST). Primary outcomes included days from surgery to discontinuation of PN and goal enteral feeds, and total days on PN. Secondary outcomes were related to PN hepatotoxicity. RESULTS: Thirteen RF and eleven OST were identified. There were no significant differences among markers of critical illness (p>0.20). In the interoperative period, RF patients reached goal enteral feeds earlier than OST patients (median 28 versus 43days; p=0.03) and were able to have PN discontinued earlier (median 25 versus 41days; p=0.04). Following anastomosis, the magnitude of effect was more pronounced, with RF patients reaching goal enteral feeds earlier than OST patients (median 7.5 versus 20days; p≤0.001) and having PN discontinued sooner (30.5 versus 48days; p=0.001). CONCLUSIONS: RF neonates reached goal feeds and were able to be weaned from PN sooner than OST patients. A prospective multicenter trial of refeeding is needed to define the benefits and potential side effects of refeeding in a larger patient population in varied care environments.

Lung assist device technology with physiologic blood flow developed on a tissue engineered scaffold platform.

There is no technology available to support failing lung function for patients outside the hospital. An implantable lung assist device would augment lung function as a bridge to transplant or possible destination therapy. Utilizing biomimetic design principles, a microfluidic vascular network was developed for blood inflow from the pulmonary artery and blood return to the left atrium. Computational fluid dynamics analysis was used to optimize blood flow within the vascular network. A micro milled variable depth mold with 3D features was created to achieve both physiologic blood flow and shear stress. Gas exchange occurs across a thin silicone membrane between the vascular network and adjacent alveolar chamber with flowing oxygen. The device had a surface area of 23.1 cm(2) and respiratory membrane thickness of 8.7 ± 1.2 µm. Carbon dioxide transfer within the device was 156 ml min(-1) m(-2) and the oxygen transfer was 34 ml min(-1) m(-2). A lung assist device based on tissue engineering architecture achieves gas exchange comparable to hollow fiber oxygenators yet does so while maintaining physiologic blood flow. This device may be scaled up to create an implantable ambulatory lung assist device.

Principles of biomimetic vascular network design applied to a tissue-engineered liver scaffold.

Branched vascular networks are a central component of scaffold architecture for solid organ tissue engineering. In this work, seven biomimetic principles were established as the major guiding technical design considerations of a branched vascular network for a tissue-engineered scaffold. These biomimetic design principles were applied to a branched radial architecture to develop a liver-specific vascular network. Iterative design changes and computational fluid dynamic analysis were used to optimize the network before mold manufacturing. The vascular network mold was created using a new mold technique that achieves a 1:1 aspect ratio for all channels. In vitro blood flow testing confirmed the physiologic hemodynamics of the network as predicted by computational fluid dynamic analysis. These results indicate that this biomimetic liver vascular network design will provide a foundation for developing complex vascular networks for solid organ tissue engineering that achieve physiologic blood flow.

Poly(glycerol sebacate) films prevent postoperative adhesions and allow laparoscopic placement.

BACKGROUND: The objectives of this study were to evaluate the efficacy of poly(glycerol) sebacate (PGS) films for the prevention of visceroparietal peritoneal (VP) adhesions and demonstrate the ease of laparoscopic PGS film placement. Peritoneal adhesions occur in nearly 95% of all abdominal operations. VP adhesions can cause serious postoperative complications. The interposition of a barrier between damaged peritoneal areas during re-epithelialization has been shown to prevent adhesion formation. Current barrier products have serious drawbacks, including poor degradability, variable efficacy, and difficult handling characteristics. METHODS: The efficacy of PGS films to prevent VP adhesions was evaluated in a rat peritoneal adhesion model. The animals were evaluated for the presence of VP adhesions at 3, 5, and 8 weeks. The laparoscopic applicability of PGS films was demonstrated by placement into a juvenile porcine abdomen using standard laparoscopic equipment and techniques. RESULTS: A statistically significant 94% reduction in VP adhesion formation rate was observed between control animals (75%) and animals with a PGS film barrier (4.8%). PGS films were easily placed in the juvenile porcine abdomen and could be readily repositioned without material loss or tissue damage. CONCLUSION: PGS films possess a unique combination of properties, including biocompatibility, resorbability, and ease of handling. PGS barrier films were shown to be efficacious in reducing VP adhesions in the rat model. They also can be placed using standard laparoscopic techniques. These promising results suggest that PGS films will be effective barriers to adhesion formation for patients undergoing open and laparoscopic abdominal operations.

Tissue engineering and organ structure: a vascularized approach to liver and lung.

Over the past two decades, great strides have been made in the field of tissue engineering. Many of the initial attempts to develop an engineered tissue construct were based on the concept of seeding cells onto an avascular scaffold. Using advanced manufacturing technologies, the creation of a preformed vascular scaffold has become a reality. This article discusses some of the issues surrounding the development of such a vascular scaffold. We then examine of the challenges associated with applying this scaffold technology to two vital organ constructs: liver and lung.