Preceding Clinical Events in High-risk, Postoperative, Pediatric Cardiac Patients-A Novel Association With Bacteremia.

Objective: Blood stream infections (BSIs) are well described in pediatric cardiac intensive care units (PCICU). We noted that postoperative high-risk patients may develop BSI after a preceding clinical event (PCE). The study aim was to investigate whether high-risk patients who developed bacteremia experienced more PCEs than a similar group of high-risk patients. Design: Retrospective case-control study. Setting: Referral pediatric center. Patients: We enrolled patients who developed bacteremia from March 2010 to November 2019, after undergoing open-heart surgery at a pediatric center. The control group was comprised of case-matched patients with immediate consecutive same surgery. Interventions: None. Measurements: We recorded operative data, common risk factors, postoperative indicators of organ dysfunction, mortality, and PCEs 72 to 24 h before bacteremia emerged. Main results: A total of 200 patients were included (100 with bacteremia and 100 controls). Key demographic and operative parameters were matched. Bacteremia emerged on average on postoperative day 12.8. Skin-associated Gram-positive bacteria were cultured in 10% and Gram-negative bacteria in 84% of the patients. Average central-venous lines (CVL) duration was 9.5 ± 8.4 days. Postoperatively (72 h), indicators of organ dysfunction were significantly worse in patients with bacteremia, with a higher rate of postoperative complications during PCICU length-of-stay (LOS). In the bacteremia group, 72 to 24 h prior to the development of bacteremia, 92 (92%) PCEs were recorded, as compared to 21 (21%) in controls during their entire LOS (odds ratio [OR] 43.3, confidence interval [CI] 18.2-103.1, P < .0001). Conclusions: We propose a 3-hit model demonstrating that high-risk patients undergoing open-heart surgery have significantly higher risk for bacteremia after a PCE.

Comparisons of Continuous-wave Doppler Ultrasound Monitor and Echocardiography in Cardiac Postoperative Pediatric Patients.

RATIONAL AND OBJECTIVES: Non-invasive cardiac output (CO) measurements are essential during the immediate post-operative course of young, congenital heart repaired patients. The use of the Ultrasonic Cardiac Output Monitor (USCOM) in pediatric intensive care units (PICU) is increasing. The literature on accuracy of USCOM in young, critically ill, mechanically ventilated, hemodynamically supported patients is scarce. We aimed to assess agreement between the USCOM device and echocardiography for measurements of CO in this population. MATERIALS (PATIENTS) AND METHODS: A prospective observational study in a pediatric cardiac intensive care unit (PCICU). Paired CO measurements were taken in young, mechanically ventilated, immediate post-operative patients with exclusion of unrepaired or residual intra-cardiac shunt, using USCOM and echocardiography, by two separate senior performers. Agreement between echocardiography and USCOM was assessed by percentage error and Bland-Altman analysis. RESULTS: One hundred and thirteen comparison scans were performed on 61 patients: mean age 94 ± 111 d, weight 4.7 ± 2.1 kg, vaso-inotropic score 15.3 ± 11, and STAT score 3-4 (46%). Mean USCOM cardiac index (CI) percent difference was -9.6% (45.6) and velocity-time-integral (VTI) 8.9% (34.7). Bland-Altman analyzes demonstrated poor agreement comparing USCOM to echocardiography with regard to CI, stroke volume (SV), VTI and aortic diameter (AO) measurements. CONCLUSION: Our study shows that USCOM underestimates CI in comparison with echocardiography; therefore USCOM should be used with great caution as an absolute estimate or surrogate of CI in neonates and infants in the immediate post-operative, congenital heart surgery period.

Fluid Responsiveness Predictability in Immediate Postoperative Pediatric Cardiac Surgery. Is the Old Slandered Central Venous Pressure Back Again?

OBJECTIVE: Acute low cardiac output (CO) is a frequent scenario in pediatric cardiac intensive care units (PCICU). While fluid responsiveness has been studied extensively, literature is scarce for the immediate postoperative congenital heart surgery population admitted to PCICUs. This study analyzed the utility of hemodynamic, bedside ultrasound, and Doppler parameters for prediction of fluid responsiveness in infants and neonates in the immediate postoperative cardiac surgery period. DESIGN: A prospective observational study. SETTING: University affiliated, tertiary care hospital, PCICU. PARTICIPANTS: Immediate postoperative pediatric patients displaying a presumed hypovolemic low CO state were included. A clinical, arterial derived, hemodynamic, sonographic, Doppler-based, and echocardiographic parameter assessment was performed, followed by a fluid bolus therapy. INTERVENTIONS: Fifteen to 20 cc/kg crystalloid fluid bolus. MAIN OUTCOME MEASURES: Fluid responsiveness was defined as an increase in cardiac index >10% by echocardiography. RESULTS: Of 52 patients, 34 (65%) were fluid responsive. Arterial systolic pressure variation, continuous-Doppler preload parameters, and inferior vena-cava distensibility index (IVCDI) by bedside ultrasound all failed to predict fluid responsiveness. Dynamic central venous pressure (CVP) change yielded a significant but modest fluid responsiveness predictability of area under the curve 0.654 (P = 0.0375). CONCLUSIONS: In a distinct population of mechanically ventilated, young, pediatric cardiac patients in the immediate postoperative period, SPV, USCOM preload parameters, as well as IVC-based parameters by bedside ultrasound failed to predict fluid responsiveness. Dynamic CVP change over several hours was the only parameter that yielded significant but modest fluid responsiveness predictability.

Extracorporeal Membrane Oxygenation as a Rescue Therapy for Postoperative Diastolic Dysfunction and Refractory Chylothorax.

This is the first published case, as far as we know, of a term neonate with refractory chylothorax secondary to diastolic dysfunction in the cardiac postoperative period, where extracorporeal membrane oxygenation (ECMO) was used to improve the physiologic derangements, thus allowing resolution of the chylous effusion. The infant was prenatally diagnosed with d-transposition of the great arteries. He was started on prostaglandin infusion and underwent balloon atrial septostomy followed by arterial switch operation. After surgery, he developed anasarca and high-volume chylothorax that did not respond to medical management and fasting. Cardiac catheterization demonstrated severe diastolic dysfunction and pulmonary hypertension. On postoperative day 19, he was placed on veno-arterial (VA) ECMO and had gradual regression of the chylothorax and edema. After 13 days on ECMO support, he was decannulated with small, self-limiting, reaccumulation of chylous effusion. He was discharged home on postoperative day 57, and has since been thriving with no evidence of reaccumulation of the chylous effusion. In summary, VA ECMO support could be considered as a rescue modality for patients with uncontrollable refractory high-volume chylous effusion, after other treatment options have been pursued.

The Utility of Albumin Level as a Marker of Postoperative Course in Infants Undergoing Repair of Congenital Heart Disease.

We sought to examine the role of preoperative and 2nd postoperative day albumin levels as predictors for postoperative course in infants undergoing repair of congenital heart disease. This retrospective, single-center, observational study comprised consecutive infants younger than 1 year who had undergone repair of tetralogy of Fallot, ventricular septal defect, complete atrioventricular canal or transposition of the great arteries over a 25 months period. We correlated preoperative and postoperative day (POD) #2 albumin level to vaso-inotropic score (VIS) and intensive care unit (ICU) length of stay (LOS) as markers for degree and duration of postoperative cardiac support. A composite outcome was defined as maximal vaso-inotropic score of > 10 and ICU LOS > 96 h. Preoperative albumin level negatively correlated with VIS and ICU LOS. Compared to preoperative albumin level of > 4 g/dL, the relative risk of meeting composite criteria was 1.5 for preoperative albumin of 3.1-4 g/dL and 2.6 for preoperative albumin ≤ 3 g/dL. Compared to POD#2 albumin level > 3 g/dL, the relative risk of meeting composite criteria was 1.8 for albumin of 2.6-3 g/dL, and 2.5 for albumin ≤ 2.5 g/dL. In summary, we found that preoperative and POD#2 albumin levels predicted prolonged and complicated postoperative course. These finding may help clinicians to inform the patient's parents, early in the ICU hospitalization, as to the predicted risks and difficulties of their infant's postoperative course.

Pediatric Extracorporeal Membrane Oxygenation Reach-Out Program: Successes and Insights.

The shortage of dedicated pediatric extracorporeal membrane oxygenation (ECMO) centers and the expanding indications for pediatric ECMO necessitate a regional program for transport of ECMO-supported patients. Data about feasibly and safety of pediatric ECMO transport are scarce. Our aim is to describe our experience with a pediatric ECMO reach-out program and review pertinent literature. Demographic, clinical, and outcome data were collected retrospectively from the charts of all patients cannulated onto ECMO at referring centers and transported to our center from 2003 to 2018. Similar data were recorded for patients who were referred for ECMO support from within the hospital. The cohort included 80 patients cannulated at 17 referring centers. The transport team included a senior pediatric cardiac surgeon and an ECMO specialist. All transfers but one were done by special emergency medical service ambulance. No major complications or deaths occurred during transport, and all patients were stable upon arrival to our unit. Mortality was lower in the ECMO reach-out cohort than in-house patients referred for ECMO support. This is the first study from Israel and one of the largest to date describing a dedicated pediatric ECMO transport program. Extracorporeal membrane oxygenation transport appears to be feasible and safe when conducted by a small, highly skilled mobile team. Successful reach-out program requires open communication between the referring physician and the accepting center. As survival correlates with ECMO volume, maintaining a large ECMO center with 24/7 retrieval capabilities may be the best strategy for pediatric mechanical circulatory support program.

Vacuum-Assisted Closure for the Treatment of Deep Sternal Wound Infection After Pediatric Cardiac Surgery.

OBJECTIVES: Vacuum-assisted closure is being increasingly used to treat deep sternal wound infection following cardiac surgery, but most of the data refer to adults. This study investigated the safety and efficacy of vacuum-assisted closure in pediatric patients. DESIGN: Retrospective file review. SETTING: Tertiary pediatric medical center. PATIENTS: All children with deep sternal wound infection treated with vacuum-assisted closure in 2003-2016. INTERVENTIONS: Epidemiological, clinical, and microbiological data were collected from the medical records. MEASUREMENTS AND MAIN RESULTS: The cohort included 50 patients (0.9% of cardiac patients operated during the study period) of median age 6.5 months (interquartile range, 2-12.75 mo; range, 1 wk to 14 yr) and median weight 5.1 kg (interquartile range, 4-9.75 kg). The most frequent heart defects were tetralogy of Fallot (22%) and ventricular septal defect (20%); 38% of patients had cyanotic heart disease. Deep sternal wound infections appeared a median of 10 days postoperatively (interquartile range, 7-14 d; range 3-100 d). Vacuum-assisted closure was applied a median of 13 days postoperatively (interquartile range, 10-18.5 d; range, 5-103 d) for a median duration of 10 days (interquartile range, 7-13.25 d; range, 1-21 d). Wound cultures were positive in 48 patients (96%); most isolates were Gram-positive (76%). The main bacterial pathogen was methicillin-susceptible Staphylococcus aureus (61%). Most patients were treated with cloxacillin for a median of 38 days (interquartile range, 28-42 d; range, 9-189 d). There were no statistically significant differences in clinical or treatment characteristics between bacteremic (56%) and nonbacteremic patients. Compared with older patients, infants less than 3 months old (36%) had a significantly longer hospitalization time (41 vs 25 d; p = 0.001) and higher Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery Mortality Category (3 vs 2; p = 0.003). All cases except one (contact dermatitis) were uneventful. In 10 patients, wounds were closed surgically after vacuum-assisted closure. Two patients required a pectoralis flap, both treated before 2005. One of the two deaths was infection-related. CONCLUSIONS: Vacuum-assisted closure is a feasible treatment option of deep sternal wound infection after pediatric cardiac surgery and was not associated with independent morbidity.