Golf cart injuries have similar severity to all-terrain vehicle injuries in children: a multicenter comparison over a 5-year period.

Background: Golf carts (GCs) and all-terrain vehicles (ATVs) are popular forms of personal transport. Although ATVs are considered adventurous and dangerous, GCs are perceived to be safer. Anecdotal experience suggests increasing numbers of both GC and ATV injuries, as well as high severity of GC injuries in children. This multicenter study examined GC and ATV injuries and compared their injury patterns, resource utilization, and outcomes. Methods: Pediatric trauma centers in Florida submitted trauma registry patients age <16 years from January 2016 to June 2021. Patients with GC or ATV mechanisms were identified. Temporal trends were evaluated. Injury patterns, resource utilization, and outcomes for GCs and ATVs were compared. Intensive care unit admission and immediate surgery needs were compared using multivariable logistic regression. Results: We identified 179 GC and 496 ATV injuries from 10 trauma centers. GC and ATV injuries both increased during the study period (R2 0.4286, 0.5946, respectively). GC patients were younger (median 11 vs 12 years, p=0.003) and had more intracranial injuries (34% vs 19%, p<0.0001). Overall Injury Severity Score (5 vs 5, p=0.27), intensive care unit (ICU) admission (20% vs 16%, p=0.24), immediate surgery (11% vs 11%, p=0.96), and mortality (1.7% vs 1.4%, p=0.72) were similar for GCs and ATVs, respectively. The risk of ICU admission (OR 1.19, 95% CI 0.74 to 1.93, p=0.47) and immediate surgery (OR 1.04, 95% CI 0.58 to 1.84, p=0.90) remained similar on multivariable logistic regression. Conclusions: During the study period, GC and ATV injuries increased. Despite their innocuous perception, GCs had a similar injury burden to ATVs. Heightened safety measures for GCs should be considered. Level of evidence: III, prognostic/epidemiological.

Optimizing Triage Practice in Pediatric Trauma: Lessons From Under-triage and Over-triage Rates and Risk Factors.

BACKGROUND: Triage accuracy is essential for delivering effective trauma care, especially in the pediatric population where unique challenges exist. The purpose of this study was to investigate risk factors contributing to under-triage and over-triage in an urban pediatric trauma center. METHODS: This retrospective cohort study included all trauma activations at an urban level 1 trauma center between January 1, 2021, and July 31, 2023 (patients <18 years old.) Patients who were under- or over-triaged were identified based on the level of trauma activation and injury severity score. RESULTS: There were 1094 trauma activations included in this study. The rate of under-triage was 3.8% (n = 42) and over-triage was 13.6% (n = 149). Infants aged 0-1 years had the highest rate of under-triage (10.9%, n = 19, P < .001), while those aged 11-17 had the highest rate of over-triage (17.0%, n = 82, P = .003). Non-accidental trauma was the strongest risk factor for under-triage (OR 30.2 [6.4-142.8] P < .001). Penetrating mechanism was the strongest risk factor for over-triage (OR 12.2 [5.6-26.2] P < .001). DISCUSSION: This study reveals the complexity of trauma triage in the pediatric population. We identified key predictive factors, such as age, comorbidities, and mechanism of injury, that can be used to refine triage practices and improve the care of pediatric trauma patients.

Social determinants of health in pediatric trauma: Associations with injury mechanisms and outcomes in the context of the COVID-19 pandemic.

BACKGROUND: Relationships between social determinants of health and pediatric trauma mechanisms and outcomes are unclear in context of COVID-19. METHODS: Children <16 years old injured between 2016 and 2021 from ten pediatric trauma centers in Florida were included. Patients were stratified by high vs. low Social Vulnerability Index (SVI). Injury mechanisms studied were child abuse, ATV/golf carts, and firearms. Mechanism incidence trends and mortality were evaluated by interrupted time series and multivariable logistic regression. RESULTS: Of 19,319 children, 68% and 32% had high and low SVI, respectively. Child abuse increased across SVI strata and did not change with COVID. ATV/golf cart injuries increased after COVID among children with low SVI. Firearm injuries increased after COVID among children with high SVI. Mortality was predicted by injury mechanism, but was not independently associated with SVI, race, or COVID. CONCLUSION: Social vulnerability influences pediatric trauma mechanisms and COVID effects. Child abuse and firearm injuries should be targeted for prevention.

Laparoscopic transperitoneal repair of pediatric diaphragm eventration using an endostapler device.

BACKGROUND: Minimally invasive repairs of pediatric diaphragm eventration have been well described via a thoracoscopic approach, oftentimes requiring single-lung ventilation and tube thoracostomy, with the disadvantage of not being able to clearly visualize what lies beneath the diaphragm. We describe a novel pediatric diaphragm eventration repair using a laparoscopic transperitoneal approach and an endostapler device. We also describe our initial experience with this technique. PATIENTS AND METHODS: Four pediatric diaphragmatic eventration patients underwent laparoscopic transperitoneal repair using an endostapler device. Repairs were performed in both male and female patients with right-sided eventrations. We approach the repair in a transperitoneal fashion using inverting sutures at the apex of the diaphragm to create tension toward the pelvis. Subsequently, an endostapler is used to remove the redundant portion of diaphragm, leaving a repaired, taut diaphragm. RESULTS: The median age at operation was 10.5 months. The median operative time was 70 minutes. There was no mortality, surgical complications, or recurrence at a median follow-up of 17 months. CONCLUSIONS: This laparoscopic approach allows for clear visualization of the intraabdominal organs and, at least in our early experience, a very simple, straightforward operation. Additionally, with the use of the endostapler, the redundant, often weakened diaphragm is removed, leaving the native, healthy diaphragm behind, resulting in a reliable and reproducible repair. This repair should be considered as a feasible alternative approach to the more traditional open and thoracoscopic repairs.

Hepatic artery thrombosis and liver malignancy in pediatric liver transplantation.

BACKGROUND: Hepatic artery thrombosis (HAT) remains a significant cause of graft failure and mortality after pediatric liver transplantation. Conditions not associated with hepatic failure, such as liver tumors, may be more prone to thrombotic problems after transplant. We hypothesized that liver transplant for hepatic malignancies may be associated with increased rates of HAT in the posttransplant period. METHODS: We conducted a retrospective review of pediatric patients (age, 0-21 years) who underwent primary liver transplantation at a free-standing children's hospital from 1990 to 2009. We reviewed cause of underlying liver disease, age, sex, weight, occurrence of HAT, use of antiplatelets and anticoagulants perioperatively, as well as reintervention, retransplant, and death. RESULTS: A total of 129 children underwent 146 liver transplants, and 15 (12%) patients developed HAT. Nine liver transplants were performed for hepatic malignancy, and 4 (44%) of these patients developed HAT (relative risk, 4.85; 95% confidence interval, 1.9-12.2; P = .0015). All 4 children with hepatic malignancy and HAT required reintervention, including 3 retransplants (75%). One of these patients died. CONCLUSIONS: Hepatic artery thrombosis occurs approximately 5 times more often and appears to be more morbid in children with hepatic malignancy after transplantation. Prospective evaluation of prophylactic anticoagulation regimens in the setting of hepatic malignancy requiring transplantation is warranted.

Pediatric inguinal hernias, hydroceles, and undescended testicles.

Pediatric inguinal hernias are extremely common, and can usually be diagnosed by simple history taking and physical examination. Repair is elective, unless there is incarceration or strangulation. Hydroceles are also quite common, and in infancy many will resolve without operative intervention. Undescended testicles harbor an increased risk of infertility and malignancy, and require orchiopexy in early childhood.

Postoperative Bowel Perforation due to Heterotopic Ossification (Myositis Ossificans Traumatica): A Case Report and Review of the Literature.

Heterotopic ossification (HO) is the ectopic development of normal bone within soft tissue that can occur after traumatic injury. It is uncommon and may be missed or misdiagnosed, which can lead to complications. We report the case of an 84-year-old male with a previous history of a laparotomy who underwent resection of an intra-abdominal tumor through a midline incision. On postoperative day six, the patient was taken to the operating room, as succus was draining from the incision. Upon re-exploration, sharp bone-like material was found in the wound directly adjacent to an enterotomy. Pathology confirmed mature lamellar bone and the diagnosis of HO. This is the first report of postoperative intestinal perforation secondary to HO in a midline wound. We report this case to encourage accurate reporting of HO and its morbidity and complications for the benefit of appropriate surgical planning and epidemiologic tracking of outcomes.

Identifying the futile pediatric liver re-transplant in the PELD era.

Survival following pediatric re-transplant is inferior to that following primary transplant. We analyzed UNOS data (1987-2007) to identify factors associated with poor outcomes following re-transplant in both the pre-PELD and PELD eras. There may be a combination of factors associated with a futile pediatric liver re-transplant. Identification of these factors may improve allograft allocation and survival following re-transplantation. Abstract: Survival following pediatric liver re-transplant is distinctly inferior to that following primary transplant. The purpose of this study was to determine factors associated with futile pediatric liver re-transplants before and after introduction of the PELD criteria in February 2002. We analyzed the UNOS database (1987-2008) and identified pediatric patients requiring liver re-transplants before and after PELD criteria. Descriptive characteristics were evaluated and survival analyzed with Cox proportional hazards method. Analysis of 1248 children identified re-transplant survival in the PELD era was significantly better than the pre-PELD era. Multivariable analysis in the pre-PELD era identified number of re-transplants, African American race, ICU pretransplant, recipient weight, creatinine and bilirubin levels, donor age, and cold ischemia time to be significantly associated with poor survival. In the PELD era, ICU hospitalization, weight, and very high bilirubin levels were associated with poor survival. Kaplan-Meier analysis by risk groups demonstrated a significant difference in survival, with the highest risk group experiencing 40-50% one-yr survival. Survival following pediatric liver re-transplantation varies significantly by era and associated risk factors. There may be a combination of factors that predict a futile re-transplant. Pre-operative identification of these factors may improve allograft allocation and recipient survival following re-transplantation.

Impact of obesity on children undergoing liver transplantation.

Controversies exist with respect to the mortality of patients undergoing liver transplantation at the extremes of the body mass index (BMI). For pediatric liver transplantation, weight is usually the only factor considered in survival analysis. A review of the United Network for Organ Sharing database (1987-2007) revealed 9701 pediatric patients (<18 years old) who underwent primary liver transplantation. Patients were stratified into 5 BMI categories established by the World Health Organization according to their Z score, which was based on age, gender, and BMI: -3, -2, 0, +2, and +3. The survival rates in these 5 categories were compared with Kaplan-Meier survival curves and log-rank testing. Patients with thinness (Z score = -2) and severe thinness (Z score = -3) had significantly (P < 0.0001) lower survival at 1 year (84.4%) versus the survival (88.7%) of the normal and overweight groups (Z score = 0 and Z score = + 2, respectively). For patients with obesity (Z score = +3), there was no significant difference in survival early after transplantation, but their mortality gradually increased in the later years after transplantation. By 12 years after liver transplantation, the obese group had significantly (P = 0.04) lower survival (72%) than the normal and overweight groups (77%). In conclusion, liver transplantation holds increased risk for obese pediatric patients. Thin pediatric patients experience early mortality after liver transplantation, and obese pediatric patients experience late mortality after liver transplantation. Transplant management can be modified to optimize the care of these patients.

The biopsied donor liver: incorporating macrosteatosis into high-risk donor assessment.

To expand the donor liver pool, ways are sought to better define the limits of marginally transplantable organs. The Donor Risk Index (DRI) lists 7 donor characteristics, together with cold ischemia time and location of the donor, as risk factors for graft failure. We hypothesized that donor hepatic steatosis is an additional independent risk factor. We analyzed the Scientific Registry of Transplant Recipients for all adult liver transplants performed from October 1, 2003, through February 6, 2008, with grafts from deceased donors to identify donor characteristics and procurement logistics parameters predictive of decreased graft survival. A proportional hazard model of donor variables, including percent steatosis from higher-risk donors, was created with graft survival as the primary outcome. Of 21,777 transplants, 5051 donors had percent macrovesicular steatosis recorded on donor liver biopsy. Compared to the 16,726 donors with no recorded liver biopsy, the donors with biopsied livers had a higher DRI, were older and more obese, and a higher percentage died from anoxia or stroke than from head trauma. The donors whose livers were biopsied became our study group. Factors most strongly associated with graft failure at 1 year after transplantation with livers from this high-risk donor group were donor age, donor liver macrovesicular steatosis, cold ischemia time, and donation after cardiac death status. In conclusion, in a high-risk donor group, macrovesicular steatosis is an independent risk factor for graft survival, along with other factors of the DRI including donor age, donor race, donation after cardiac death status, and cold ischemia time.

Extracorporeal life support for adults with malignancy and respiratory or cardiac failure: The Extracorporeal Life Support experience.

BACKGROUND: Adults with cancer may be considered for extracorporeal life support (ECLS) as a means of support if failing conventional therapy. METHODS: The Extracorporeal Life Support Organization Registry was queried for patients aged >or=21 years with diagnoses of malignancy or hematopoietic stem cell transplantation. RESULTS: Seventy-two adults met inclusion criteria: 47 with solid tumors, 21 with hematologic malignancies, and 4 with hematopoietic stem cell transplantation. Patients required ECLS primarily for pulmonary support (n = 54). The median duration of ECLS was 4.1 days. Overall, 44 patients (61%) died on ECLS, 23 (32%) survived to hospital discharge, and 5 (7%) survived ECLS but died before discharge. Risk factors for death include pulmonary support as reason for ECLS, impaired lung function before ECLS, and development of infection. CONCLUSIONS: Adults with cancer can be offered ECLS with a small but real expectation for survival. Impaired pulmonary status and the development of infections are associated with death.

Steroid use after the Kasai procedure for biliary atresia.

BACKGROUND: The aim of this study was to describe patients undergoing the Kasai procedure at children's hospitals, evaluate outcomes, and analyze the association of these outcomes with systemic steroid use. METHODS: Biliary atresia patients (International Classification of Diseases, Ninth Revision, code 751.61) who underwent Kasai procedures at freestanding children's hospitals in the Pediatric Health Information System database from 2003 to 2008 were identified. Descriptive characteristics were examined, and regression analyses were used to determine whether postoperative steroid use was associated with length of stay, mortality, or cholangitis. RESULTS: Of the 516 children identified (40% male, 50% aged < 2 months), 239 (46%) received perioperative steroids. The mean total and postoperative lengths of stay were 14.5 +/- 19.7 and 11.3 +/- 16.3 days, respectively. Postoperative steroid use was significantly associated with a 3.5-day decrease in postoperative length of stay (95% confidence interval, .03-6.97). CONCLUSIONS: Perioperative steroids after the Kasai procedure are associated with shorter postoperative length of stay. Work is needed to ascertain whether this relationship is causal.

Outcomes in children after intestinal transplant.

OBJECTIVE: The survival rates after pediatric intestinal transplant according to underlying disease are unknown. The objective of our study was to describe the population of pediatric patients receiving an intestinal transplant and to evaluate survival according to specific disease condition. PATIENTS: Pediatric patients (< or =21 years of age) with intestinal failure meeting criteria for intestinal transplant were included in the study. METHODS: A retrospective review of the United Network for Organ Sharing intestinal transplant database (January 1, 1991, to May 16, 2008), including all pediatric transplant centers participating in the United Network for Organ Sharing, was conducted. The main outcome measures were survival and mortality. RESULTS: Eight hundred fifty-two children received an intestinal transplant (54% male). Median age and weight at the time of transplant were 1 year (interquartile rage: 1-5) and 10.7 kg (interquartile rage: 7.8-21.7). Sixty-nine percent of patients also received a simultaneous liver transplant. The most common diagnoses among patients who received a transplant were gastroschisis (24%), necrotizing enterocolitis (15%), volvulus (14%), other causes of short-gut syndrome (19%), functional bowel syndrome (16%), and Hirschsprung disease (7%). The Kaplan-Meier curves demonstrated variation in patient survival according to diagnosis. Cox regression analysis confirmed a survival difference according to diagnosis (P < .001) and demonstrated a survival advantage for those patients listed with a diagnosis of volvulus (P < .01) compared with the reference gastroschisis. After adjusting for gender, recipient weight, and concomitant liver transplant, children with volvulus had a lower hazard ratio for survival and a lower risk of mortality. CONCLUSIONS: Survival after intestinal transplant was associated with the underlying disease state. The explanation for these findings requires additional investigation into the differences in characteristics of the population of children with intestinal failure.

Outcomes in children with intestinal failure following listing for intestinal transplant.

PURPOSE: The purpose of this study was to describe the population of pediatric patients waiting for intestinal transplant and to evaluate the risk of death or transplant by specific disease states. METHODS: We studied the United Network for Organ Sharing (UNOS) database (Jan 1,1991 to 5/16/08) for patients 21 years old or younger at first listing for intestinal transplant and examined their age, sex, weight, and diagnoses. Time to list removal was summarized with cumulative incidence curves. Multinomial logistic regression was used to compare relative risk ratios for removal from the list for transplant, death, or other reasons. RESULTS: We identified 1712 children listed for intestinal transplant (57% male, 51% <1 year, weight 8.1 kg [IQR, 6.1-14.1] at listing). Median age and weight at transplant (n = 852) were 1 year (IQR, 1-5) and 10 kg (IQR, 6.5-16.3). Regression analysis demonstrated significant differences in outcomes among disease conditions (P < .001). Compared to the gastroschisis group, the relative risk ratio for death versus transplant was higher in the necrotizing enterocolitis group (P = .015), lower in the short gut syndrome group (P = .001), and not different in the volvulus group (P = .94) after adjustment for weight and sex. CONCLUSIONS: We conclude that the relative risk of transplant vs death varies significantly by the disease condition of the patient.

Thoracoscopic repair of congenital diaphragmatic hernia in infancy.

BACKGROUND: Minimally invasive surgical techniques, specifically the thoracoscopic approach, have been applied to congenital diaphragmatic hernia (CDH) with varying outcomes from selected centers. The aim of our study was to examine the rate of successful completion and compare outcomes between open and thoracoscopic approaches in CDH repair. METHODS: We performed a retrospective analysis of infants with CDH repair (From February 2004 to January 2008). Patients were divided into thoracoscopic and open groups, based on operative approach. We analyzed demographic, clinical, and hospitalization characteristics to compare the completion rate and outcomes in these two groups. RESULTS: Analysis of 31 infants with CDH (14 thorascocopic and 17 open) demonstrated no differences in sex (P = 0.132), age (P = 0.807), birthweight (P = 0.256), weight at operation (P = 0.647), pulmonary hypertension (P = 0.067), preoperative intensive care unit (ICU) days (P = 0.673), ventilator days (P = 0.944), or use of a patch (P = 0.999) between the groups. Seventy-nine percent of thoracoscopic operative approaches were completed successfully. There was a significant difference between the open and thoracoscopic groups with respect to estimated gestational age (39 versus 36.5 weeks; P = 0.006) and operating room time (70 versus 145 minutes; P = 0.004). The total (P = 0.662), ICU (P = 0.889), and postoperative (P = 0.619) length of stay and days on ventilator (P = 0.705), as well as days until initial enteral feeds (P = 0.092), were not significantly different between groups. There were no deaths and no evidence of recurrence, with a mean follow-up of 346 days. CONCLUSIONS: In our early experience, the thoracoscopic approach for congenital diaphragmatic hernia repair was completed in 80% of our patient population with minimal exclusion criteria. Further study, with larger sample sizes, is needed to ascertain differences in outcomes, such as length of stay and initiation of enteral feeding.

Outcomes in neonates with gastroschisis in U.S. children's hospitals.

Our objectives are to report patient characteristics, comorbidities, and outcomes for gastroschisis patients and analyze factors associated with mortality and sepsis. Using Pediatric Health Information System data, we examined neonates with both an International Classification of Diseases, 9th Revision diagnosis (756.79) and procedure (54.71) code for gastroschisis (2003 to 2008). We examined descriptive characteristics and conducted multivariate regression models examining risk factors for mortality, during the birth hospitalization, and sepsis. Analysis of 2490 neonates with gastroschisis found 90 deaths (3.6%) and sepsis in 766 (31%). Critical comorbidities and procedures are cardiovascular defects (15%), pulmonary conditions (5%), intestinal atresia (11%), intestinal resection (12.5%), and ostomy formation (8.3%). Factors associated with mortality were large bowel resection (odds ratio [OR] 8.26, 95% confidence interval [CI] 1.17 to 58.17), congenital circulatory (OR 5.62, 95% CI 2.11 to 14.91), and pulmonary (OR 8.22, 95% CI 2.75 to 24.58) disease, and sepsis (OR 3.87, 95% CI 1.51 to 9.91). Factors associated with sepsis include intestinal ostomy (OR 2.94, 95% CI 1.71 to 5.05), respiratory failure (OR 2.48, 95% CI 1.85 to 3.34), congenital circulatory anomalies (OR 1.58, 95% CI 1.10 to 2.28), and necrotizing enterocolitis (OR 4.38, 95% CI 2.51 to 7.67). Further investigation into modifiable factors such as small bowel ostomy and prevention of sepsis and necrotizing enterocolitis is warranted to guide surgical decision making and postoperative management.

Pre-transplant therapy for hepatocellular carcinoma is associated with a lower recurrence after liver transplantation.

BACKGROUND: Hepatic transplantation has been advocated as an effective treatment for hepatocellular carcinoma (HCC). We seek to determine if pre-transplant therapies can reduce post-transplant recurrence. METHODS: We conducted a retrospective review of prospective data in patients undergoing transplantation for HCC 2001-2006. Patients were followed for recurrence every six months with abdominal computerized tomography or magnetic resonance imaging. Logistic regression analyzed recipient factors such as prior treatment for HCC, donor, operative, and tumor factors in comparing patients developing HCC recurrence with those without recurrence. RESULTS: During the study period, we performed 124 hepatic transplants for HCC [age: 55 +/- 7.6 yr; 104 (85%) male, 81 (66%) white, and 32 (26%) Asian]. Recurrence was found in nine at a mean of 2.6 yr follow-up. Thirty-three patients (27%) had pre-transplant treatment (radiofrequency ablation, transarterial chemoembolization or percutaneous ethanol injection). Univariable logistic regression identified nine factors [body mass index, Asian race, hepatitis B, prior HCC therapy, alpha-fetoprotein (AFP), model for end-stage liver disease (MELD) score, bilirubin, and international normalized ratio] predictive of HCC recurrence at a level of p < 0.1. Multiple logistic regression analysis of six of the nine selected factors demonstrated AFP level >1000, calculated pre-transplant MELD score <14, and the lack of any pre-transplant treatment were significantly associated with recurrence of HCC. No patient with prior HCC therapy had recurrence. CONCLUSIONS: In patients with HCC awaiting hepatic transplantation, there is a reduced rate of recurrence of HCC if tumors are pre-treated with liver-directed therapy. By treating HCC tumors with any type of treatment prior to transplant, we can significantly reduce the odds of HCC recurrence after transplant.

Adverse events after radiofrequency ablation of unresectable liver tumors: a single-center experience.

BACKGROUND: Radiofrequency ablation (RFA) is a relatively new modality to treat liver tumors that is being incorporated into practice despite the fact that its risk profile has not been well described. METHODS: A retrospective cohort study, using structured chart review, on patients with liver tumor(s) was conducted from August 1998 to November 2006. Univariate and multivariate exploratory analyses were used to evaluate factors associated with adverse events. RESULTS: RFA procedures were performed on 196 patients (58% primary tumors, 24% colorectal metastases, and 18% other metastases). Twenty-three patients (12%) experienced serious adverse events. Multivariate analysis showed advanced age (>or=55 y), underlying liver disease, large tumor size (>4 cm), and concomitant procedure were associated with an increased risk of adverse events (P = .01, P < .01, P = .01, and P = .01, respectively). There were no in-hospital deaths. CONCLUSIONS: RFA was associated with acceptable morbidity and mortality. Factors associated with adverse events should be considered when counseling patients regarding RFA procedures.

Synchronous Todani types I and III choledochal cysts in a 10-month-old-infant: type IVb.

A 10-month-old, previously healthy boy presented with one week of mild jaundice, light-colored stools and irritability. Abdominal sonography showed a large type I choledochal cyst and a separate, distinct cystic mass at the head of the pancreas. Magnetic resonance cholangiopancreatography was performed to evaluate the relationship of the two lesions. A type I choledochal cyst was confirmed, and a coexisting type III choledochocele was identified as the second cystic structure in conjunction with pancreaticobiliary malunion. The infant had complete resection of the type I choledochal cyst with Roux-en-Y hepaticojejunostomy, and anterior duodenotomy with marsupialization of the choledochocele. After five years of follow-up, the child is thriving and has had no recurrence of his symptoms. An exhaustive review of the literature identifies only one previous case of synchronous types I and III choledochal cysts, and this association is not clearly defined among the traditional classifications of type IV multiple choledochal cysts. Because operative management of a type III cyst requires the addition of a transduodenal approach, we encourage accurate reporting of mixed type choledochal cysts for the benefit of surgical planning, epidemiologic tracking and outcomes.

Physiologic properties of small intestine submucosa.

BACKGROUND: Porcine small intestine submucosa (SiS) has been introduced as a bioprosthesis in herniorrhaphy. This study evaluates in vivo properties of SiS that would affect clinical use. MATERIALS AND METHODS: Twelve pigs underwent implantation of SiS (perforated and nonperforated) on the peritoneal surface. Gross characteristics were evaluated and random samples harvested for histological study at 2 (n = 6) and 8 (n = 6) weeks. Collagen deposition was determined by polarized microscopy. Neovascularity (percent area blood vessels, %A(bv)) was determined by immunohistochemical staining with a polyclonal CD-31 antibody. RESULTS: Perforated SiS had a higher density of capillary ingrowth compared with nonperforated at both 2 (5.6%A(bv) versus 1.4%A(bv), P < 0.05) and 8 weeks (6.0%A(bv) versus 1.6%A(bv), P < 0.05). Compared with 2 weeks, 8-week SiS had a larger proportion of incorporation (25% versus 83%, P < 0.05) and new collagen deposition (50% versus 94%, P < 0.05). Significant contraction was observed in SiS 8 weeks after implantation (preimplant area 98 cm2 versus post-implant area 50 cm2, P < 0.05). CONCLUSION: SiS incorporated well 8 weeks after implantation, with deposition of new collagen. Perforated SiS demonstrated a more rapid and greater amount of neovascularity. The degree of contraction suggests that larger areas of SiS should be selected for herniorrhaphy than would be necessary if synthetic materials were used.