Modes of Death in a Pediatric Cardiac ICU.

OBJECTIVE: To determine epidemiology and proximate causes of death in a pediatric cardiac ICU in Southern Europe. DESIGN: Retrospective chart review. SETTING: Single-center institution. PATIENTS: We concurrently identified 57 consecutive patients who died prior to discharge from the cardiac ICU. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Over the study period, there were 57 deaths for a combined mortality rate of 2.4%. Four patients (7%) were declared brain dead, 25 patients (43.8%) died after a failed resuscitation attempt, and 28 patients (49.1%) died after withholding or withdrawal of life-sustaining treatment. Cardiorespiratory failure was the most frequent proximate cause of death (39, 68.4%) followed by brain injury (14, 24.6%) and septic shock (4, 7%). Older age at admission, presence of mechanical ventilation and/or device-dependent nutrition support, patients on a left-ventricular assist device and longer cardiac ICU stay were more likely to have life support withheld or withdrawn. CONCLUSIONS: Almost half of the deaths in the cardiac ICU are predictable, and they are anticipated by the decision to limit life-sustaining treatments. Brain injuries play a direct role in the death of 25% of patients who die in the cardiac ICU. Patients with left-ventricular assist device are associated with withdrawal of treatment.

Comparative evaluation of high-flow nasal cannula and conventional oxygen therapy in paediatric cardiac surgical patients: a randomized controlled trial.

OBJECTIVES: The aim of this study was to compare high-flow nasal cannula (HFNC) and conventional O2 therapy (OT) in paediatric cardiac surgical patients; the primary objective of the study was to evaluate whether HFNC was able to improve PaCO2 elimination in the first 48 h after extubation postoperatively. METHODS: We conducted a randomized, controlled trial in pediatric cardiac surgical patients under 18 months of age. At the beginning of the weaning of ventilation, patients were randomly assigned to either of the following groups: OT or HFNC. Arterial blood samples were collected before and after extubation at the following time points: 1, 6, 12, 24 and 48 h. The primary outcome was comparison of arterial PaCO2 postextubation; secondary outcomes were PaO2 and PaO2/fractional inspired oxygen (FiO2) ratio, rate of treatment failure and need of respiratory support, rate of extubation failure, rate of atelectasis, simply to complications and the length of paediatric cardiac intensive care unit stay. RESULTS: Demographic and clinical variables were comparable in the two groups. Analysis of variance for repeated measures showed that PaCO2 was not significantly different between the HFNC and OT groups (P = 0.5), whereas PaO2 and PaO2/FiO2 were significantly improved in the HFNC group (P = 0.01 and P = 0.001). The rate of reintubation was not different in the two groups (P = 1.0), whereas the need for noninvasive respiratory support was 15% in the OT group and none in the HFNC group (P = 0.008). CONCLUSIONS: HFNC had no impact on PaCO2 values. The use of HFNC appeared to be safe and improved PaO2 in paediatric cardiac surgical patients.

Pediatric RIFLE for acute kidney injury diagnosis and prognosis for children undergoing cardiac surgery: a single-center prospective observational study.

This study evaluated the performance of the pediatric RIFLE (pRIFLE) score for acute kidney injury (AKI) diagnosis and prognosis after pediatric cardiac surgery. It was a single-center prospective observational study developed in a pediatric cardiac intensive care unit (pCICU) of a tertiary children's hospital. The study enrolled 160 consecutive children younger than 1 year with congenital heart diseases and undergoing cardiac surgery with cardiopulmonary bypass. Of the 160 children, 50 (31 %) were neonates, and 20 (12 %) had a univentricular heart. Palliative surgery was performed for 53 patients (33 %). A diagnosis of AKI was determined for 90 patients (56 %), and 68 (42 %) of these patients achieved an "R" level of AKI severity, 17 patients (10 %) an "I" level, and 5 patients (3 %) an "F" level. Longer cross-clamp times (p = 0.045), a higher inotropic score (p = 0.02), and a higher Risk-Adjusted Classification for Congenital Heart Surgery score (p = 0.048) but not age (p = 0.27) correlated significantly with pRIFLE class severity. Patients classified with a higher pRIFLE score required a greater number of mechanical ventilation days (p = 0.03) and a longer pCICU stay (p = 0.045). Renal replacement therapy (RRT) was needed for 13 patients (8.1 %), with two patients receiving continuous hemofiltration, and 11 patients receiving peritoneal dialysis. At the start of dialysis, the distribution of RRT patients differed significantly within pRIFLE classes (p = 0.015). All deceased patients were classified as pRIFLE "I" or "F" (p = 0.0001). The findings showed that pRIFLE is easily and feasibly applied for pediatric patients with congenital heart disease. The pRIFLE classification showed that AKI incidence in pediatric cardiac surgery infants is high and associated with poorer outcomes.

Whole blood assessment of neutrophil gelatinase-associated lipocalin versus pediatricRIFLE for acute kidney injury diagnosis and prognosis after pediatric cardiac surgery: cross-sectional study*.

OBJECTIVE: To assess the ability of a single whole blood neutrophil gelatinase-associated lipocalin measurement in predicting acute kidney injury occurrence, its severity, and the need for postoperative renal replacement therapy after pediatric cardiac surgery. DESIGN: Single-center prospective cross-sectional study. SETTING: Tertiary care pediatric cardiac intensive care unit. PATIENTS: Consecutive children <1 yr old with congenital heart diseases undergoing cardiac surgery with cardiopulmonary bypass. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Neutrophil gelatinase-associated lipocalin levels were measured after pediatric cardiac intensive care unit admission. Pediatric score indicating level of renal damage by Risk, Injury, Failure, Loss of function and End-stage kidney disease (pRIFLE) was used as the reference method. Acute kidney injury was diagnosed in 90 (56%) of the 160 enrolled patients. The number of abnormal neutrophil gelatinase-associated lipocalin samples (above the cutoff level of 150 ng/mL) was 12 over 90 (13%) in acute kidney injury population and 6 over 70 in non-acute kidney injury patients (8%) (odds ratio 1.6; 95% confidence interval 0.6-4.7; p = .31). Sensitivity of neutrophil gelatinase-associated lipocalin for acute kidney injury detection was 0.13 and specificity 0.91. The number of patients with abnormal neutrophil gelatinase-associated lipocalin samples was not significantly different within pediatric score indicating level of renal damage by pRIFLE (p = .69); furthermore, we found abnormal neutrophil gelatinase-associated lipocalin levels in 4 (30%) over 13 renal replacement therapy patients and in 14 (10%) over 133 children without renal replacement therapy need (odds ratio 4.2; 95% confidence interval 1.2-10.2; p = .02). Mean cross-clamp time (p = .28), inotropic score (p = .19), surgical risk score (p = .3), mean length of mechanical ventilation (p = .48), and pediatric cardiac intensive care unit stay (p = .57) did not significantly differ between children with abnormal and normal neutrophil gelatinase-associated lipocalin values. CONCLUSIONS: Neutrophil gelatinase-associated lipocalin measured at pediatric cardiac intensive care unit arrival does not accurately predict acute kidney injury diagnosis, according to pediatric score indicating level of renal damage by pRIFLE classification. In these patients, neutrophil gelatinase-associated lipocalin might be helpful for renal replacement therapy prediction.

Renal replacement therapy in neonates with congenital heart disease.

BACKGROUND: The acute renal failure (ARF) incidence in pediatric cardiac surgery intensive care unit (ICU) ranges from 5 to 20% of patients. In particular, clinical features of neonatal ARF are mostly represented by fluid retention, anasarca and only slight creatinine increase; this is the reason why medical strategies to prevent and manage ARF have limited efficacy and early optimization of renal replacement therapy (RRT) plays a key role in the outcome of cardiopathic patients. METHODS: Data on neonates admitted to our ICU were prospectively collected over a 6-month period and analysis of patients with ARF analyzed. Indications for RRT were oligoanuria (urine output less than 0.5 ml/kg/h for more than 4 h) and/or a need for additional ultrafiltration in edematous patients despite aggressive diuretic therapy. RESULTS: Incidence of ARF and need for RRT were equivalent and occurred in 10% of admitted neonates. Eleven patients of 12 were treated by peritoneal dialysis (PD) as only RRT strategy. PD allowed ultrafiltration to range between 5 and 20 ml/h with a negative balance of up to 200 ml over 24 h. Creatinine clearance achieved by PD ranged from 2 to 10 ml/min/1.73 m2. We reported a 16% mortality in RRT patients. CONCLUSION: PD is a safe and adequate strategy to support ARF in neonates with congenital heart disease. Fluid balance control is easily optimized by this therapy whereas solute control reaches acceptable levels.

Cerebral blood flow during cardiopulmonary bypass in pediatric cardiac surgery: the role of transcranial Doppler--a systematic review of the literature.

BACKGROUND: Transcranial Doppler Ultrasound (TCD) is a sensitive, real time tool for monitoring cerebral blood flow velocity (CBFV). This technique is fast, accurate, reproducible and noninvasive. In the setting of congenital heart surgery, TCD finds application in the evaluation of cerebral blood flow variations during cardiopulmonary bypass (CPB). METHODOLOGY: We performed a search on human studies published on the MEDLINE using the keyword "trans cranial Doppler" crossed with "pediatric cardiac surgery" AND "cardio pulmonary by pass", OR deep hypothermic cardiac arrest", OR "neurological monitoring". DISCUSSION: Current scientific evidence suggests a good correlation between changes in cbral blood flow and mean cerebral artery (MCA) blood flow velocity. The introduction of Doppler technology has allowed an accurate monitorization of cerebral blood flow (CBF) during circulatory arrest and low-flow CPB. TCD has also been utilized in detecting cerebral emboli, improper cannulation or cross clamping of aortic arch vessels. Limitations of TCD routine utilization are represented by the need of a learning curve and some experience by the operators, as well as the need of implementing CBF informations with, for example, data on brain tissue oxygen delivery and consumption. CONCLUSION: In this light, TCD plays an essential role in multimodal neurological monitorization during CPB (Near Infrared Spectroscopy, TCD, processed electro encephalography) that, according to recent studies, can help to significantly improve neurological outcome after cardiac surgery in neonates and pediatric patients.