Santiago Borasino

Prophylactic Peritoneal Dialysis Following Cardiopulmonary Bypass in Children Is Associated with Decreased Inflammation and Improved Clinical Outcomes

OBJECTIVE To investigate impact of prophylactic peritoneal dialysis (PD) on clinical outcomes and inflammatory cytokines in children following cardiac surgery with cardiopulmonary bypass. DESIGN Prospective before-and-after nonrandomized cohort study. SETTING Pediatric cardiovascular intensive care unit in tertiary hospital. PATIENTS Fifty-two consecutive neonates and infants at high risk for postoperative fluid overload following cardiopulmonary bypass. All had PD catheters placed during primary cardiac surgery. INTERVENTION Initial 27 patients were managed with passive peritoneal drainage and diuretics (controls). Following 25 patients were started on prophylactic PD in immediate postoperative period and managed per PD protocol (+PD). OUTCOME MEASURES Cumulative fluid balance, indices of disease severity, and clinical outcomes were prospectively collected. Plasma interleukin-6 and interleukin-8 were measured immediately before-and-after cardiopulmonary bypass and at 24 and 48 hours post-cardiopulmonary bypass. RESULTS Demographics, diagnoses, and intraoperative variables were similar. Median net fluid balance was more negative in +PD at 24 hours, -24 mL/kg (interquartile range: -62, 11) vs. +18 mL/kg (interquartile range: -26, 11), P = .003, and 48 hours, -88 mL/kg (interquartile range: -132, -54) vs. -46 mL/kg (interquartile range: -84, -12), P = .004. +PD had median 55 mL/kg less fluid intake at 24 hours, P = .058. Peritoneal drain, urine, and chest tube output were comparable over first 24 hours. Mean inotrope score was lower in +PD at 24 hours. +PD had earlier sternal closure--24 hours (interquartile range: 20, 40) vs. 63 hours (interquartile range: 44, 72), P < .001--and a trend toward shorter duration of mechanical ventilation--71 hours (interquartile range: 49, 135) vs. 125 hours (interquartile range: 70, 195), P = .10. +PD experienced lower serum concentrations of interleukin-6 and interleukin-8 at 24 hours. CONCLUSIONS Prophylactic PD is associated with greater net negative fluid balance, decreased inotrope requirements, and lower serum concentrations of inflammatory cytokines in the early postoperative period.

Differences in medical therapy goals for children with severe traumatic brain injury-an international study.

Objectives: To describe the differences in goals for their usual practice for various medical therapies from a number of international centers for children with severe traumatic brain injury. Design: A survey of the goals from representatives of the international centers. Setting: Thirty-two pediatric traumatic brain injury centers in the United States, United Kingdom, France, and Spain. Patients: None. Interventions: None. Measurements and Main Results: A survey instrument was developed that required free-form responses from the centers regarding their usual practice goals for topics of intracranial hypertension therapies, hypoxia/ischemia prevention and detection, and metabolic support. Cerebrospinal fluid diversion strategies varied both across centers and within centers, with roughly equal proportion of centers adopting a strategy of continuous cerebrospinal fluid diversion and a strategy of no cerebrospinal fluid diversion. Use of mannitol and hypertonic saline for hyperosmolar therapies was widespread among centers (90.1% and 96.9%, respectively). Of centers using hypertonic saline, 3% saline preparations were the most common but many other concentrations were in common use. Routine hyperventilation was not reported as a standard goal and 31.3% of centers currently use PbO2 monitoring for cerebral hypoxia. The time to start nutritional support and glucose administration varied widely, with nutritional support beginning before 96 hours and glucose administration being started earlier in most centers. Conclusions: There were marked differences in medical goals for children with severe traumatic brain injury across our international consortium, and these differences seemed to be greatest in areas with the weakest evidence in the literature. Future studies that determine the superiority of the various medical therapies outlined within our survey would be a significant advance for the pediatric neurotrauma field and may lead to new standards of care and improved study designs for clinical trials.

Early initiation of arginine vasopressin infusion in neonates after complex cardiac surgery.

Objective: To describe our experience with low-dose arginine vasopressin infusions (0.0003 U/kg/min) initiated in the operating room after the Norwood procedure or arterial switch operation. Design: Retrospective cohort study of 37 consecutive neonates. Setting: Pediatric cardiovascular intensive care unit in a tertiary hospital. Subjects: Nineteen patients that received low-dose arginine vasopressin infusion instituted in the operating room (arginine vasopressin+) were compared to 18 patients that did not receive early arginine vasopressin infusion (arginine vasopressin–). Interventions: None. Results: When comparing arginine vasopressin+ and arginine vasopressin− in the first 24 hrs after cardiovascular intensive care unit admission, there was no difference in demographic variables, heart rate, blood pressure, central venous pressure, maximum lactate, maximum arterial and central venous saturation difference, urine output, chest tube output, or peritoneal drain output. Mean fluid resuscitation in the first 24 hrs was significantly lower in the arginine vasopressin+ group compared to the arginine vasopressin− group (182 ± 61 mL/kg vs. 223 ± 53 mL/kg, p = .03). The arginine vasopressin+ group also reached median net negative cumulative fluid balance sooner (55 hrs: interquartile range 45, 74 vs. 76 hrs: interquartile range 69, 92; p = .02). Median maximum inotrope score in the first 24 hrs was significantly lower in arginine vasopressin+ (9: interquartile range 5, 12.5 vs. 16.5: interquartile range 10.3, 22.1; p = .02). There was a nonsignificant trend toward shorter duration of mechanical ventilation and cardiovascular intensive care unit length of stay in the arginine vasopressin+ group. The lowest serum sodium in the first 48 hrs was significantly lower in arginine vasopressin+ (132 vs. 137 mmol/L, p = .01). Conclusion: Low-dose arginine vasopressin infusion initiated in the operating room after complex neonatal cardiac surgery was associated with decreased fluid resuscitation and catecholamine requirements in the first 24 postoperative hours.

Postoperative Hydrocortisone Infusion Reduces the Prevalence of Low Cardiac Output Syndrome After Neonatal Cardiopulmonary Bypass.

Objective: Neonatal cardiac surgery with cardiopulmonary bypass is often complicated by morbidity associated with inflammation and low cardiac output syndrome. Hydrocortisone “stress dosing” is reported to provide hemodynamic benefits in some patients with refractory shock. Development of cardiopulmonary bypass-induced adrenal insufficiency may provide further rationale for postoperative hydrocortisone administration. We sought to determine whether prophylactic, postoperative hydrocortisone infusion could decrease prevalence of low cardiac output syndrome after neonatal cardiac surgery with cardiopulmonary bypass. Design: Double-blind, randomized control trial. Setting: Pediatric cardiac ICU and operating room in tertiary care center. Patients: Forty neonates undergoing cardiac surgery with cardiopulmonary bypass were randomized (19 hydrocortisone and 21 placebo). Demographics and known risk factors were similar between groups. Interventions: After cardiopulmonary bypass separation, bolus hydrocortisone (50 mg/m2) or placebo was administered, followed by continuous hydrocortisone infusion (50 mg/m2/d) or placebo tapered over 5 days. Adrenocorticotropic hormone stimulation testing (1 &mgr;g) was performed before and after cardiopulmonary bypass, prior to steroid administration. Blood was collected for cytokine analysis before and after cardiopulmonary bypass. Measurements and Main Results: Subjects receiving hydrocortisone were less likely to develop low cardiac output syndrome (5/19, 26% vs 12/21, 57%; p = 0.049). Hydrocortisone group had more negative net fluid balance at 48 hours (–114 vs –64 mL/kg; p = 0.01) and greater urine output at 0–24 hours (2.7 vs 1.2 mL/kg/hr; p = 0.03). Hydrocortisone group weaned off catecholamines and vasopressin sooner than placebo, with a difference in inotrope-free subjects apparent after 48 hours (p = 0.033). Five placebo subjects (24%) compared with no hydrocortisone subjects required rescue steroids (p = 0.02). Thirteen (32.5%) had adrenal insufficiency after cardiopulmonary bypass. Patients with adrenal insufficiency randomized to receive hydrocortisone had lower prevalence of low cardiac output syndrome compared with patients with adrenal insufficiency randomized to placebo (1/6 vs 6/7, respectively; p = 0.02). Hydrocortisone significantly reduced proinflammatory cytokines. Ventilator-free days, hospital length of stay, and kidney injury were similar. Conclusions: Prophylactic, postoperative hydrocortisone reduces low cardiac output syndrome, improves fluid balance and urine output, and attenuates inflammation after neonatal cardiopulmonary bypass surgery. Further studies are necessary to show if these benefits lead to improvements in more important clinical outcomes.

Early High-Frequency Oscillatory Ventilation in Pediatric Acute Respiratory Failure. A Propensity Score Analysis

RATIONALE The use of high-frequency oscillatory ventilation (HFOV) for acute respiratory failure in children is prevalent despite the lack of efficacy data. OBJECTIVES To compare the outcomes of patients with acute respiratory failure managed with HFOV within 24-48 hours of endotracheal intubation with those receiving conventional mechanical ventilation (CMV) and/or late HFOV. METHODS This is a secondary analysis of data from the RESTORE (Randomized Evaluation of Sedation Titration for Respiratory Failure) study, a prospective cluster randomized clinical trial conducted between 2009 and 2013 in 31 U.S. pediatric intensive care units. Propensity score analysis, including degree of hypoxia in the model, compared the duration of mechanical ventilation and mortality of patients treated with early HFOV matched with those treated with CMV/late HFOV. MEASUREMENTS AND MAIN RESULTS Among 2,449 subjects enrolled in RESTORE, 353 patients (14%) were ever supported on HFOV, of which 210 (59%) had HFOV initiated within 24-48 hours of intubation. The propensity score model predicting the probability of receiving early HFOV included 1,064 patients (181 early HFOV vs. 883 CMV/late HFOV) with significant hypoxia (oxygenation index ≥ 8). The degree of hypoxia was the most significant contributor to the propensity score model. After adjusting for risk category, early HFOV use was associated with a longer duration of mechanical ventilation (hazard ratio, 0.75; 95% confidence interval, 0.64-0.89; P = 0.001) but not with mortality (odds ratio, 1.28; 95% confidence interval, 0.92-1.79; P = 0.15) compared with CMV/late HFOV. CONCLUSIONS In adjusted models including important oxygenation variables, early HFOV was associated with a longer duration of mechanical ventilation. These analyses make supporting the current approach to HFOV less convincing.

Ultrasound-guided femoral vein catheterization in neonates with cardiac disease*.

Objective: To describe a novel technique for real-time, ultrasound-guided femoral vein catheterization in neonates with cardiac disease, and to compare it to a contemporaneous cohort of neonates undergoing femoral vein central venous line placement via landmark technique. Design: Retrospective cohort study of data extracted from a quality improvement database. Setting: Pediatric cardiac intensive care unit and cardiovascular operating room in pediatric tertiary hospital. Patients: One hundred fifteen neonates (mean weight, 3.07 ± 0.41 kg) with cardiac disease who underwent femoral central venous line attempts from January 2009 to September 2011. Measurements and Main Results: Study populations were similar in age, weight, and Risk Adjustment for Congenital Heart Surgery-1 category, but differed in intubation status (32% vs. 100%, ultrasound vs. landmark, p < .0001). Central venous line success rate was superior in the ultrasound group: 72 of the 76 (94.7%) vs. 31 of the 39 (79.5%), p = .02. Ultrasound group also had a superior first (75% vs. 30.8 %) and second attempt success rate (90.8% vs. 51.3%), p value for both < .0001. Inadvertent arterial puncture occurred less frequently in the ultrasound group: four of the 76 (5.3%) vs. nine of the 39 (23.1%), p = .01. There was a trend toward more venous thrombosis in the landmark group, 16 of the 39 (41%) vs. 18 of the 76 (23.7%), p = .08. Among all 115 subjects, there was a very strong association between greater than two central venous line attempts and the odds of being diagnosed with a deep venous thrombosis (odds ratio, 9.3; 95% confidence interval 3.5–24.8) and the odds of suffering an inadvertent femoral arterial puncture during the central venous line event (odds ratio, 8.8; 95% confidence interval 10.6–730). Conclusions: This novel long-axis real-time ultrasound technique facilitates placement of femoral vein central venous line in critically ill neonates with cardiac disease at a higher rate of success with fewer attempts and lower occurrence of complications when compared with the landmark technique.

Side-Arm Grafts for Femoral Extracorporeal Membrane Oxygenation Cannulation

Lower extremity ischemia is an important source of morbidity with femoral venoarterial extracorporeal membrane oxygenation support. We describe our experience with the use of a side-arm graft sewn to the femoral artery that facilitates adequate extracorporeal membrane oxygenation flow while preventing lower extremity ischemia.

Implantation of the HeartWare HVAD in a Child After a Recent Thromboembolic Stroke

We report the implantation of a HeartWare left ventricular assist device in a child. A 9-year-old girl presented in cardiogenic shock complicated by an embolic stroke. Catheter-based thrombolysis partially reversed the neurologic deficit, but worsening cardiac failure prompted consideration of mechanical circulatory support (MCS). Limited available pericardial space, anticoagulation requirements, and thromboembolic potential favored the use of the HeartWare left ventricular assist device (HeartWare International, Inc, Framingham, MA). After device implantation and intensive physical rehabilitation, the patient underwent successful cardiac transplantation after 60 days of support.

Patterns of Sedation Weaning in Critically Ill Children Recovering From Acute Respiratory Failure.

Objective: To characterize sedation weaning patterns in typical practice settings among children recovering from critical illness. Design: A descriptive secondary analysis of data that were prospectively collected during the prerandomization phase (January to July 2009) of a clinical trial of sedation management. Setting: Twenty-two PICUs across the United States. Patients: The sample included 145 patients, aged 2 weeks to 17 years, mechanically ventilated for acute respiratory failure who received at least five consecutive days of opioid exposure. Interventions: None. Measurements and Main Results: Group comparisons were made between patients with an intermittent weaning pattern, defined as a 20% or greater increase in daily opioid dose after the start of weaning, and the remaining patients defined as having a steady weaning pattern. Demographic and clinical characteristics, tolerance to sedatives, and iatrogenic withdrawal symptoms were evaluated. Sixty-six patients (46%) were intermittently weaned; 79 patients were steadily weaned. Prior to weaning, intermittently weaned patients received higher peak and cumulative doses and longer exposures to opioids and benzodiazepines, demonstrated more sedative tolerance (58% vs 41%), and received more chloral hydrate and barbiturates compared with steadily weaned patients. During weaning, intermittently weaned patients assessed for withdrawal had a higher incidence of Withdrawal Assessment Tool-version 1 scores of greater than or equal to 3 (85% vs 46%) and received more sedative classes compared with steadily weaned patients. Conclusions: This study characterizes sedative administration practices for pediatric patients prior to and during weaning from sedation after critical illness. It provides a novel methodology for describing weaning in an at-risk pediatric population that may be helpful in future research on weaning strategies to prevent iatrogenic withdrawal syndrome.

Central Venous Lines Are a Risk Factor for Chylothorax in Infants After Cardiac Surgery

Objective: Chylothorax complicates congenital heart disease (CHD) surgery and may be associated with significant morbidity. Etiology of chylothorax is multifactorial, and it has been associated with deep venous thrombosis and obstruction from central venous lines (CVLs) in patients without CHD. We sought to determine whether CVL insertion site was associated with the occurrence of chylothorax in infants after cardiac surgery. Design: Retrospective cohort of patients less than one year of age who underwent CHD surgery requiring cardiopulmonary bypass from 2008 to 2012. Chylothorax was identified by clinical diagnosis and/or laboratory findings (milky effusion, fluid with >100 mg/dL of triglycerides and/or >80% of lymphocytes). Central venous lines insertion site was verified by reviewing procedure notes and chest x-rays. Internal jugular (IJ), subclavian vein, and femoral vein (FV) CVLs were used during the study period. Results: Three hundred and ninety-two patients were included (mean age 97 days, mean weight 4.5 kg). Sixty-two (15.8%) of these patients developed chylothorax after surgery. Patients with chylothorax had longer bypass time (P = .02), longer cross-clamp time (P = .03), higher RACHS-1 category (P = .03), and more frequent upper body CVLs (IJ or subclavian vein; P = .03). There was no significant association with age, gender, preoperative weight, and height. Multivariate analysis showed patients with a CVL in the upper body (IJ or subclavian vein) were almost two times more likely to develop a chylothorax than patients who had FV CVL, (odds ratio = 1.9, 95% confidence interval = 1.05-5.60; P = .044). Conclusion: Postoperative chylothorax is associated with line insertion in the upper body (subclavian vein and IJ). Avoidance of CVLs in these locations may decrease its incidence.