Low cardiac output syndrome in children

Is there an association of near-infrared spectroscopy with low cardiac output and adverse outcomes in single-ventricle patients after stage 1 palliation?

Objective

Our primary objective study was to evaluate the association between near-infrared spectroscopy (NIRS) and low cardiac output (LCO) in patients with single-ventricle physiology after stage 1 palliation.

Methods

In this retrospective study, infants ≤6 months of age with single-ventricle physiology who underwent stage 1 palliation were included. Cerebral and renal NIRS values at various time intervals after surgery were compared between patients with low and normal cardiac output. LCO within the first 48 after surgery was defined as per the pediatric cardiac critical care consortium database. NIRS values were also compared with other adverse outcomes such as cardiac arrest, need for extracorporeal membrane oxygenation and mortality. The receiver operative characteristic curve was generated to determine an optimal cut-off NIRS value for detecting LCO.

Results

Ninety-one patients with median (Interquartile range) age of 10 days (6-26) and weight of 3.3 kg (3-3.5) were included in the study. Cerebral NIRS at 1 h (41.2 vs. 49.5; P = 0.002), 6 h (44 vs. 52.2; P = 0.001), and 12 h (51.8 vs. 56; P = 0.025) was significantly lower in the grouP with LCO compared to no LCO. Cerebral NIRS at 6 h was independently associated with LCO (P = 0.018), and cerebral NIRS at 6 h ≤57% had 91% sensitivity and 72% specificity to detect LCO.

Conclusions

Cerebral NIRS ≤57% at 6 h after surgery detected LCO after stage 1 palliation in single-ventricle patients. Cerebral or renal NIRS was not associated with adverse outcomes and therefore, may not be useful in predicting adverse outcomes in this population.

Adult congenital heart disease: frequency, risk factors and outcomes of acute kidney injury in postoperative period

Background

Acute kidney injury (AKI) after surgery for congenital heart disease (CHD) in adults is poorly studied despite being well-recognized as a postoperative complication after cardiac surgery in adults. The primary aim of our study was to determine the frequency of AKI in adults undergoing surgery for CHD. We also aimed to determine risk factors and predictors of AKI in this patient population, and to explore outcomes in terms of duration of mechanical ventilation, intensive care unit (ICU) stay, and hospital stay.

Methods

This retrospective cross-sectional study included all adult patients (18 years) who underwent cardiac surgery with cardiopulmonary bypass for their congenital heart problems from January 2011 to December 2016 in a tertiary-care private hospital.

Results

A total of 166 patients with a mean age of 32.05 ± 12.11 years were included in this study. The postoperative course was complicated by AKI in 29.5% of patients. Thirty-two percent of these patients had moderate-to-severe kidney disease. Two patients (4%) developing AKI required renal replacement therapy in the form of transient hemodialysis. All patients in our study showed complete resolution of AKI, with no mortalities in the postoperative period. On univariable analysis, (Risk adjusted classification for congenital heart surgery-1) RACHS-1 category 2 and 3, aortic valve replacement, preoperative creatinine clearance, ventricular septal defect closure, cardiopulmonary bypass time, aortic cross-clamp time, intra-operative excessive blood loss, intra-operative ionotropic score, and postoperative hypotension were found to be significant predictors for the development of AKI. On age-adjusted multivariable analysis, RACHS-1 category 2 (OR = 3.49; CI = 1.22-9.95) and category 3 (OR = 3.28 = 1.15-9.36), and intra-operative excessive blood loss (OR = 2.9; CI = 1.07-7.85) were significant predictors of AKI development in the postoperative period. Moreover, development of AKI postoperatively was a predictor of a significantly longer cardiac intensive care unit (CICU) stay (OR = 1.21; CI = 1.08-1.37).

Conclusion

We found that preoperative creatinine clearance, ACC time, intraoperative excessive blood loss, and RACHS-1Category 2 and 3 are potential risk factors for postoperative AKI development. Moreover, patients who develop AKI are likely to have a significantly longer CICU stay. Our study has tried to fill the lacunae with regard to AKI in adults undergoing surgery for CHD. However, there is a need for more studies with larger cohorts involving more complex surgeries to truly estimate the incidence and potential risk factors for AKI in this group of patients.

Vasoactive Drugs and Hemodynamic Monitoring in Pediatric Cardiac Intensive Care: An Italian Survey

BACKGROUND

Little is known about practitioner preference, the availability of technology, and variability in practice with respect to hemodynamic monitoring and vasoactive drug use after congenital heart surgery. The aim of this study was to characterize current hospital practices related to the management of low cardiac output syndrome (LCOS) across Italy.

METHODS

We issued a 22-item questionnaire to 14 Italian hospitals performing pediatric cardiac surgery.

RESULTS

Electrocardiogram, invasive blood pressure, central venous pressure, pulse oximetry, diuresis, body temperature, arterial lactate, and blood gas analysis were identified as routine in hemodynamic monitoring. With regard to advanced hemodynamic monitoring, pulmonary arterial catheter and transpulmonary thermodilution were available in 43% of the centers, uncalibrated pulse contour methods in 29% of the centers, and transesophageal/transthoracic echocardiograms in all of the centers. Dopamine added to milrinone was the most frequent drug regimen for LCOS prevention after cardiopulmonary bypass. Overall, 86% of centers used milrinone alone as the initial treatment for LCOS with elevated systemic vascular resistances and levosimendan, the second preferred choice. In cases of LCOS with low vascular resistance, epinephrine was the first choice (10 centers), dopamine was the second choice (4 centers), followed by vasopressin and norepinephrine (3 centers). For treatment of LCOS with elevated pulmonary resistances, milrinone was the first choice (eight centers), followed by inhaled nitric oxide (five centers).

CONCLUSIONS

The survey shows that advanced hemodynamic monitoring is rarely performed. The most commonly used vasoactive drugs are milrinone, levosimendan, dopamine, epinephrine, vasopressin, and norepinephrine. Guidelines on the topic are warranted.

Safety, efficacy and response to a hydrocortisone rescue therapy protocol in children with refractory hypotension after cardiopulmonal bypass

Little is known about which paediatric patients respond to hydrocortisone rescue therapy (HRT) with improvement of haemodynamic stability in refractory hypotension after cardiopulmonal bypass. Data were gathered retrospectively from children who received HRT in refractory hypotension after cardiopulmonary bypass in the period from 2000 to 2010. One hundred and sixty-six out of 1,273 children, 150 <1 year and 16 >1 year were enrolled. HRT improved haemodynamics significantly, increased blood pressure, decreased the vasoactive-inotropic score and plasma lactate concentrations in all children >1 year and in 82 % (123 out of 150) of the infants <1 year. Non-responders <1 year were significantly younger, lighter, mostly male infants and had longer cardiopulmonary bypass support time. Serum lactate and paediatric risk of mortality score were significantly higher in non-responders at time of initiation of HRT. Mortality was significantly higher in non-responders versus responders (2.44 vs. 13.5 %; p = 0.0008). HRT caused no adverse effects like electrolyte disturbances or hyperglycaemia. HRT in refractory hypotension after paediatric cardiac surgery is safe but not all infants <1 year show haemodynamic response to HRT. Non-response to HRT is associated with significantly higher mortality.

Serum cortisol concentration with exploratory cut-off values do not predict the effects of hydrocortisone administration in children with low cardiac output after cardiac surgery

OBJECTIVES

Low cardiac output syndrome is common after paediatric cardiac surgery. Previous studies suggested that hydrocortisone administration may improve haemodynamic stability in case of resistant low cardiac output syndrome in critically ill children. This study was set up to test the hypothesis that the effects of hydrocortisone on haemodynamics in children with low cardiac output syndrome depend on the presence of (relative) adrenal insufficiency.

METHODS

A retrospective study was done on paediatric patients who received hydrocortisone when diagnosed with resistant low cardiac output syndrome after paediatric cardiac surgery in the period from 1 November 2005 to 31 December 2008. We studied the difference in effects of treatment with hydrocortisone administration between patients with adrenal insufficiency defined as an exploratory cut-off value of total cortisol of <100 nmol/l and patients with a serum total cortisol of ≥ 100 nmol/l.

RESULTS

A total of 62 of patients were enrolled, meeting the inclusion criteria for low cardiac output syndrome. Thirty-two patients were assigned to Group 1 (<100 nmol/l) and 30 were assigned to Group 2 (≥ 100 nmol/l). Haemodynamics improved after hydrocortisone administration, with an increase in blood pressure, a decrease in administered vasopressors and inotropic drugs, an increase in urine production and a decrease in plasma lactate concentrations.

CONCLUSIONS

The effects of treatment with hydrocortisone in children with low cardiac output after cardiac surgery was similar in patients with a low baseline serum cortisol concentration and those with normal baseline cortisol levels. A cortisol value using an exploratory cut-off value of 100 nmol/l for adrenal insufficiency should not be used as a criterion to treat these patients with hydrocortisone.