Bindi Naik-Mathuria

Parameters of Thromboelastography in Healthy Newborns

Thromboelastography (TEG) aids in monitoring a patients global hemostatic system by measuring the rate of clot formation, clot strength, and stability. The usefulness of TEG in pediatric settings, especially with neonates, is limited owing to a lack of neonatal reference values. In this study, neonatal TEG reference intervals were developed and results correlated with other coagulation test parameters. Samples were from women who delivered a neonate after at least 34 weeks of gestation in normal pregnancies. From the recovered placenta, cord blood from the umbilical vein or artery was collected within 30 minutes after delivery and tested. Neonatal TEG reaction time (time clot formation begins), clot firmness (shear elastic modulus strength), and platelet function analysis closure times were significantly lower than those in adult ranges (P< .001). When compared with the values for children, TEG reaction time, angle, coagulation index, clot firmness value, and clot kinetics (time from clot formation to time amplitude reaches 20 mm) were significantly different (P< .001) among neonates. TEG can be used to interpret the data for newborns by using reference values obtained in the present study.

Near-infrared spectroscopy measurement of abdominal tissue oxygenation is a useful indicator of intestinal blood flow and necrotizing enterocolitis in premature piglets

PURPOSE A major objective of necrotizing enterocolitis (NEC) research is to devise a noninvasive method of early detection. We hypothesized that abdominal near-infrared spectroscopy (A-NIRS) readings will identify impending NEC in a large animal model. METHODS Piglets were prematurely delivered and received parenteral nutrition followed by enteral feedings. Serial A-NIRS readings were obtained for 5 days, and animals were monitored for NEC. Separately, A-NIRS readings were obtained in healthy piglets to validate the correlation of A-NIRS with splanchnic oxygen delivery. RESULTS Of 29 piglets, 3 developed NEC. Eleven piglets without NEC died prematurely. Fifteen piglets remained healthy, had normal histologic assessment of their intestines, and served as controls. Abdominal near-infrared spectroscopy readings within 12 hours of birth were significantly lower in animals that developed NEC compared with healthy littermates (4% vs 33%, P = .02). For all time-points measured, A-NIRS readings were significantly lower in the NEC group compared with controls (21% vs 55%, P < .001). Abdominal near-infrared spectroscopy readings correlated with both decreased pulse oximetry readings during apneic episodes (r = 0.96) and increased superior mesenteric artery flow in response to glucagon-like peptide 2 (r = 0.67). CONCLUSION Abdominal near-infrared spectroscopy is capable of detecting alterations in intestinal oxygenation and perfusion in neonatal piglets and may allow early detection of neonates at risk for NEC.

Negative pressure therapy is effective to manage a variety of wounds in infants and children

Negative pressure therapy (NPT) has been accepted as a valuable adjunct for wound closure in adults; however, reports on its effectiveness in young children and infants, including neonates, are limited. A retrospective chart review was conducted on children treated with NPT at a single institution between January 2003 and December 2005. Wound volumetric measurements were calculated at the start and end of therapy. Sixty‐eight patients with 82 wounds were identified. The mean age was 8.5 years (range 7 days–18 years). Twenty patients (29%) were 2 years of age or younger, including eight neonates. Wound types included: pressure ulcers (n=13), extremity wounds (n=18), dehisced surgical wounds (n=19), open sternal wounds (n=10), wounds with fistulas (n=3), and complex abdominal wall defects (n=6). Low suction pressures (<100 mmHg) were generally used in children younger than 4 years of age. Following NPT, 93% of wounds decreased in volume. The average wound volume decrease was 80% (p<0.01, n=56). NPT can be effectively used to manage a variety of wounds in children and neonates. No major complications were identified in our retrospective review. Prospective studies are required to better refine the use of this technology in children.

Serum amyloid P inhibits dermal wound healing

The repair of open wounds depends on granulation tissue formation and contraction, which is primarily mediated by myofibroblasts. A subset of myofibroblasts originates from bone‐marrow‐derived monocytes which differentiate into fibroblast‐like cells called fibrocytes. Serum amyloid P (SAP) inhibits differentiation of monocytes into fibrocytes. Thus, we hypothesized that the addition of exogenous SAP would hinder the normal wound healing process. Excisional murine dorsal wounds were either injected with SAP (intradermal group) or the mice were treated with systemic SAP (intraperitoneal group) and compared with animals treated with vehicle. Grossly, SAP‐treated wounds closed slower than respective controls in both groups. Histologically, the contraction rate was slower in SAP‐treated wounds in both groups and the reepithelialization rate was slower in the intraperitoneal group. Furthermore, significantly less myofibroblasts expressing α‐smooth muscle actin were noted in the intraperitoneal group wounds compared with controls. These data suggest that SAP delays normal murine dermal wound healing, probably due to increased inhibition of fibrocyte differentiation, and ultimately a decreased wound myofibroblast population. SAP may provide a potential therapeutic target to prevent or limit excessive fibrosis associated with keloid or hypertrophic scar formation. Furthermore, SAP removal from wound fluid could potentially accelerate the healing of chronic, nonhealing wounds.

Delayed presentation of congenital diaphragmatic hernia manifesting as combined-type acute gastric volvulus: a case report and review of the literature.

Acute gastric volvulus associated with congenital diaphragmatic hernia is an unusual surgical emergency. We describe a case of an 11-year-old girl who presented with a 4-day history of abdominal pain, nonproductive retching, cough, and shortness of breath. A chest radiograph revealed a large air-fluid level in left hemithorax and the presence of intestinal loops with marked mediastinal deviation. Nasogastric decompression was unsuccessful. Via a thoracoscopic approach, the large fluid-filled stomach was percutaneously decompressed but could not be reduced. Through a left subcostal incision, a left-sided diaphragmatic defect about 4 x 5 cm was encountered. A large portion of small intestines, ascending and transverse colon, strangulated but viable stomach, and a large spleen herniated through the defect. The contents were reduced, revealing a combined gastric volvulus. Once the diaphragmatic defect was repaired primarily, there was insufficient space in the abdominal cavity to contain all the viscera reduced form the chest. Therefore, we placed an AlloDerm patch on the fascia and closed with a wound V.A.C (Kinetic Concepts Inc, San Antonio, TX). Two weeks later, the wound was definitively closed; she recovered uneventfully and was discharged home 3 days later. To our knowledge, only 26 previous cases of acute gastric volvulus complicating a congenital diaphragmatic hernia in children have been reported in the literature. Our patient represents the 27th case and the first combined type acute gastric volvulus case.

The importance of surgeon involvement in the evaluation of non-accidental trauma patients

INTRODUCTION Non-Accidental Trauma (NAT) is a significant cause of childhood morbidity and mortality, causing 50% of trauma-related deaths at our institution. Our purpose was to evaluate the necessity of primary surgical evaluation and admission to the trauma service for children presenting with NAT. METHODS We reviewed all NAT patients from 2007-2011. Injury types, demographic data, and hospitalization information were collected. Comparisons to accidental trauma (AT) patients were made using Wilcoxon rank sum and Students t tests. RESULTS We identified 267 NAT patients presenting with 473 acute injuries. Injuries in NAT patients were more severe than in AT patients, and Injury Severity Scores, ICU admission rates, and mortality were all significantly (p<0.001) higher. The majority suffered from polytrauma. Multiple areas of injury were seen in patients with closed head injuries (72%), extremity fractures (51%), rib fractures (82%), and abdominal/thoracic trauma (80%). Despite these complex injury patterns, only 56% received surgical consults, resulting in potential delays in diagnosis, as 24% of abdominal CT scans were obtained >12 hours after hospitalization. CONCLUSION Given the high incidence of polytrauma in NAT patients, prompt surgical evaluation is necessary to determine the scope of injury. Admission to the trauma service and a thorough tertiary survey should be considered for all patients.

Needle decompression to avoid tension pneumoperitoneum and hemodynamic compromise after pneumatic reduction of pediatric intussusception.

BackgroundThe contemporary management of children with ileocolic intussusception often includes pneumatic reduction. While failure of the procedure or recurrence after reduction can result in the need for surgical treatment, more serious adverse sequelae can occur including perforation and, rarely, tension pneumoperitoneum. During the last year, four cases of perforation during attempted pneumatic reductions complicated by tense pneumoperitoneum have occurred in our center.ObjectiveWe have elected to report our patient experience, describe methods of management and review available literature on this uncommon but serious complication.Materials and methodsUsing ICD-9 diagnosis codes, we reviewed the records of children with intussusception during 2011. Demographic and therapeutic clinical data were collected and summarized.ResultsDuring the study period, 101 children with intussusception were treated at our institution, with 19% (19/101) of them requiring surgical intervention. Four children (4%) experienced a tense pneumoperitoneum during air enema reduction, prompting urgent needle decompression in the fluoroscopy suite. These children required bowel resection during subsequent laparotomy. No deaths occurred.ConclusionPneumoperitoneum is a real and life-threatening complication of pneumatic enemas. It requires immediate intervention and definitive surgical management. Caution should be exercised by practitioners performing this procedure at institutions where pediatric radiology experience is limited and immediate pediatric surgical support is not available.

Patent ductus arteriosus ligation in neonates: preoperative predictors of poor postoperative outcomes.

PURPOSE The purpose of this study was to identify preoperative predictors of adverse outcomes in infants undergoing surgical ligation of patent ductus arteriosus (PDA). METHODS Charts of all neonates who underwent PDA ligation at Texas Childrens Hospital (Houston, TX) between 2001 and 2006 were retrospectively reviewed with specific attention to preoperative clinical characteristics, echocardiographic details, operative morbidity, and postoperative outcomes. Infants with other cardiac anomalies or right-to-left or bidirectional PDA shunt were excluded. RESULTS Eighty-two neonates were included (mean gestational age, 27 weeks; mean birth weight, 1000 g). There were no intraoperative complications. Preoperative symptoms related to respiratory insufficiency, hypotension, apnea, and pulmonary edema improved after ligation (P < .001). Birth weight, age at ligation, and indomethacin use did not correlate with postoperative outcome; however, lower gestational age, lower blood pressure, and lower shunt peak velocity predicted longer time to extubation by multiple analysis techniques (P < .0001). Linear regression (controlling for gestation, birth weight, and mean arterial pressure) showed inverse correlation between peak velocity and postoperative days on the ventilator (95% confidence interval, 47.18 to -12.25; P = .001). CONCLUSION The PDA ligation can be accomplished safely; however, some neonates have prolonged recovery. Lower gestational age and low peak velocity (<2.6 m/s) at the PDA shunt correlate with lengthened ventilator requirement after surgery.

Wound Healing Characteristics of ICAM-1 Null Mice Devoid of All Isoforms of ICAM-1

BACKGROUND Intercellular adhesion molecule-1 (ICAM-1) permits leukocyte-endothelial adhesion and transmigration during inflammation. Membrane-bound ICAM-1 knockout mice have been used to understand this molecules role in wound-healing, but expressed spliced isoforms of ICAM-1 that may have impacted results. We aimed to characterize wound-healing in an ICAM-1 null model devoid of all ICAM-1 isoforms. METHODS Full-thickness 8-mm wounds were created on C57/BL6 wild-type (n = 24) and ICAM-1 null (n = 24) mice. Wound area was calculated using daily photographs. Histologic samples were harvested on postoperative Days 1, 3, 7, and 14. Wound margins were evaluated for mRNA expression of 13 inflammatory cytokines. A separate group of wild-type and ICAM-1 null mice (n = 24) received full-thickness incisions with tensiometry measured at Day 14. Separately, complete blood counts were measured in unwounded wild-type (n = 4) and ICAM-1 null mice (n = 4). RESULTS Wound-closure was significantly delayed in ICAM-1 null mice through Day 7 by gross and histologic measurement. mRNA expression of VEGF-A was increased in ICAM-1 null mice on Day 3, although no increase in VEGF-A was observed in the wound bed by immunohistochemistry. ICAM-1 null wounds demonstrated higher stiffness by tensiometry on Day 14 compared to the wild-type (1880 ± 926 kPa versus 478 ± 117 kPa; P < 0.01), and had higher counts of white blood cells (10,009 versus 5720 cells/μL, P < 0.05), neutrophils (2130 versus 630 cells/μL, P < 0.01), and lymphocytes (7130 versus 4,740 cells/μL, P < 0.05). CONCLUSIONS ICAM-1 null mice demonstrate delayed wound-healing and decreased wound elasticity compared to wild-type controls. This lag, however, was less than observed in earlier membrane-bound ICAM-1 knockouts, suggesting that other ICAM-1 isoforms may promote delayed wound-healing.

An algorithmic approach to the management of limb ischemia in infants and young children.

Background: Vascular injuries in newborns are rare and most commonly occur in the process of obtaining vascular access for monitoring organ system functions or interventions in critical care. Care of vascular injuries in neonates poses several challenges, with the most significant arguably being the lack of clinical experience with such injuries. An algorithm for the management of arterial injuries in pediatric patients is investigated and reported. Methods: A retrospective chart analysis was performed on all patients consulted for the management of vascular injury by the plastic surgery service at Texas Childrens Hospital between 1997 and 2005. The outcomes and procedures were reviewed. Results: Thirty vascular insults in 28 patients were evaluated and treated by the senior author (J.D.F.) using this protocol. Thirty-seven percent (11 of 30) were approached surgically, including two cases treated with thrombolysis alone. The remaining 63 percent (19 of 30) were managed with more conservative interventions, including anticoagulation and clinical optimization. When color Doppler imaging was used preoperatively to locate and describe the characteristics of vascular injuries, visualized lesions coincided with the surgical findings in 100 percent (11 of 11 cases). Twenty-three limbs (77 percent) were salvaged completely using this algorithm, one was initially salvaged but later developed limb-length discrepancy requiring amputation, and one experienced complete limb loss. The remaining patients (five of 30) died as a result of complications of their primary medical conditions before limb salvage could be assessed. Conclusion: This evaluation demonstrates the efficacy of the proposed algorithm used to determine direction of care in the event of arterial injury in small children. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.