Samer Abu-Sultaneh

Changes in cerebral oxygen saturation correlate with S100B in infants undergoing cardiac surgery with cardiopulmonary bypass.

Objectives: The relationship of cerebral saturation measured by near-infrared spectroscopy with serum biomarker of brain injury S100B was investigated in infants undergoing cardiac surgery with cardiopulmonary bypass. Design: Prospective cohort study. Setting: Single-center children’s hospital. Patients: Forty infants between 1 and 12 months old weighing greater than or equal to 4 kg with congenital heart disease undergoing cardiac surgery with cardiopulmonary bypass were enrolled. Interventions: None. Measurements and Main Results: Serum S100B was measured at eight time points over 72 hours using enzyme-linked immunosorbent assay. Physiologic data including arterial, cerebral, and somatic regional oxygen saturations measured by near-infrared spectroscopy were synchronously recorded at 1-minute intervals from anesthesia induction through 72 postoperative hours. The arterial-cerebral oxygen saturation difference was calculated as the difference between arterial saturation and cerebral regional saturation. Thirty-eight patients, 5.4 ± 2.5 months old, were included in the analysis; two were excluded due to the use of postoperative extracorporeal membrane oxygenation. Seventeen patients (44.7%) had preoperative cyanosis. S100B increased during cardiopulmonary bypass in all patients, from a median preoperative baseline of mean ± SE: 0.055 ± 0.038 to a peak of 0.610 ± 0.038 ng/mL, p less than 0.0001. Patients without preoperative cyanosis had a higher S100B peak at the end of cardiopulmonary bypass. Although the absolute cerebral regional saturation on cardiopulmonary bypass was not associated with S100B elevation, patients who had arterial-cerebral oxygen saturation difference greater than 50 at any time during cardiopulmonary bypass had a higher S100B peak (mean ± SE: 1.053 ± 0.080 vs 0.504 ± 0.039 ng/mL; p < 0.0001). Conclusions: A wide cerebral arteriovenous difference measured by near-infrared spectroscopy during cardiopulmonary bypass is associated with increased serum S100B in the perioperative period and may be a modifiable risk factor for neurological injury.

Higher doses of low-molecular-weight heparin (enoxaparin) are needed to achieve target anti-Xa concentrations in critically ill children*.

Objectives: To demonstrate that low-molecular-weight heparin (enoxaparin) can be used in critically ill pediatric patients to achieve target anti-factor Xa concentrations and determine appropriate dosing corrected for age and illness severity. Design: Retrospective cohort study. Setting: Single tertiary level PICU. Patients: One hundred ninety-two children age 1 day through 18 years admitted to PICU undergoing every 12-hour enoxaparin therapy with at least one anti-factor Xa concentration obtained. Patients receiving renal replacement therapy or infants with corrected gestational age less than 37 weeks were excluded. Interventions: None. Measurements and Main Results: We collected patient characteristics including age, weight, height/length, gender, corrected gestational age, illness severity markers, diagnosis, creatinine, enoxaparin dose and times of administration, anti-factor Xa concentrations, and collection times. Only 42% of critically ill children (80 of 192) and only 29% of children (9 of 31) on inotropes achieved recommended target range of anti-factor Xa concentrations on initial recommended enoxaparin dosing (1.5 mg/kg/dose < 2 mo; 1 mg/kg/dose > 2 mo), but 81% were ultimately within target range with dose titration. Increased enoxaparin dose was required to reach target concentrations in younger patients and those with worse illness severity as evidenced by concurrent use of inotropes, previous ICU admission, mechanical ventilation, cardiac surgery, and increased risk of mortality defined by severity-of-illness scores. Conclusions: Enoxaparin can be used to reach recommended target range of anti-factor Xa concentrations in the PICU patient. However, younger patients and patients with higher illness severity are less likely to achieve target concentrations using currently recommended dosing and may require higher doses of enoxaparin to reach target anti-factor Xa concentrations. Starting enoxaparin dose at least 1.3 mg/kg dosed every 12 hours for treatment of thromboembolic disease in critically ill patients aged 61 days to 1 year or those requiring inotropic support should be confirmed in prospective study.

Devastating Ischemic Stroke Following Selective Arterial Embolization of a Large Chest Wall Aneurysmal Bone Cyst.

Aneurysmal bone cysts (ABC) are benign bone lesions found in children and young adults. Rarely, these lesions can arise from ribs, and there is disagreement on the best treatment because of proximity to vital structures. Frequently, surgeons remove ABC with en bloc resection. Selective arterial embolization has been used as an adjunct to surgery, or rarely as the primary treatment. We report a case of embolic stroke complicating embolization of a rib ABC, likely from the presence of collateral circulation between the mass and vertebral artery. Caution should be taken when performing embolization of lesions in this location because of potential complications.

Practice Variation in the Immediate Postoperative Care of Pediatric Kidney Transplantation: A National Survey

INTRODUCTION Advances in organ allocation, surgical technique, immunosuppression, and long-term follow-up have led to a significant improvement in kidney transplant outcomes. Although there are clear recommendations for several aspects of kidney transplant management, there are no pediatric-specific guidelines for immediate postoperative care. The aim of this survey is to examine practice variations in the immediate postoperative care of pediatric kidney transplant patients. METHODS We surveyed medical directors of Pediatric Acute Lung Injury and Sepsis Investigators (PALISI)-affiliated pediatric intensive care units regarding center-specific immediate postoperative management of pediatric kidney transplantation. RESULTS The majority of PALISI centers admit patients to the pediatric intensive care unit postoperatively, and 97% of the centers involve a pediatric nephrologist in immediate postoperative care. Most patients undergo invasive hemodynamic monitoring; 97% of centers monitor invasive arterial blood pressure and 88% monitor central venous pressure. Most centers monitor serum electrolytes every 4 to 6 hours. Wide variation exists regarding blood pressure goal, fluid replacement type, frequency of obtaining kidney ultrasound, and use of prophylactic anticoagulation. CONCLUSION There is consistent practice across PALISI centers in regards to many aspects of immediate postoperative management of pediatric kidney transplantation. However, variation still exists in some management aspects that warrant further discussions to reach a national consensus.

It is not always child abuse: multiple fractures due to hypophosphatemic rickets associated with elemental formula use

Rickets is not a disease of the past. We described a toddler who developed hypophosphatemic rickets associated with the use of elemental formula. This case highlights the importance of frequent monitoring of mineral metabolism in children receiving elemental formula and considering rickets in the workup of child abuse.