Characterization of the Glucocorticoid Receptor in Children Undergoing Cardiac Surgery

Definitions of low cardiac output syndrome after cardiac surgery and their effect on the incidence of intraoperative LCOS: A literature review and cohort study

Objectives

Low cardiac output syndrome (LCOS) is a serious complication after cardiac surgery. Despite scientific interest in LCOS, there is no uniform definition used in current research and clinicians cannot properly compare different study findings. We aimed to collect the LCOS definitions used in literature and subsequently applied the definitions obtained to existing data to estimate their effect on the intraoperative LCOS incidences in adults, children and infants.

Design

This is a literature review, followed by a retrospective cohort study.

Setting

This is a single-institutional study from a university hospital in the Netherlands.

Participants

Patients from all ages undergoing cardiac surgery with cardiopulmonary bypass between June 2011 and August 2018.

Interventions

We obtained different definitions of LCOS used in the literature and applied these to data obtained from an anesthesia information management system to estimate intraoperative incidences of LCOS. We compared intraoperative incidences of LCOS in different populations based on age (infants, children and adults).

Measurements and main results

The literature search identified 262 LCOS definitions, that were applied to intraoperative data from 7,366 patients. Using the 10 most frequently published LCOS definitions, the obtained incidence estimates ranged from 0.4 to 82% in infants, from 0.6 to 56% in children and from 1.5 to 91% in adults.

Conclusion

There is an important variety in definitions used to describe LCOS. When applied to data obtained from clinical care, these different definitions resulted in large distribution of intraoperative LCOS incidence rates. We therefore advocate for standardization of the LCOS definition to improve clinical understanding and enable adequate comparison of outcomes and treatment effects both in daily care and in research.

Skin-to-Skin Care Is a Safe and Effective Comfort Measure for Infants Before and After Neonatal Cardiac Surgery

OBJECTIVES

To determine the effect of skin-to-skin care on stress, pain, behavioral organization, and physiologic stability of infants with critical congenital heart disease before and after neonatal cardiac surgery.

DESIGN

A baseline response-paired design was used, with infants acting as their own controls before, during, and after skin-to-skin care at two distinct time points: once in the preoperative period (T1) and once in the postoperative period (T2).

SETTING

Cardiac ICU and step-down unit in a large metropolitan freestanding children's hospital.

SUBJECTS

Convenience sample of 30 infants admitted preoperatively for critical congenital heart disease.

INTERVENTIONS

Eligible infants were placed into skin-to-skin care for 1 hour with their biological mothers once each at T1 and T2.

MEASUREMENTS AND MAIN RESULTS

Measurements of stress (salivary cortisol), pain and behavior state (COMFORT scale), and physiologic stability (vital signs) were assessed immediately before skin-to-skin care, 30 minutes into skin-to-skin care, and 30 minutes after skin-to-skin care ended.At both T1 and T2, infant pain scores were significantly decreased (p < 0.0001) and infants moved into a calmer behavior state (p < 0.0001) during skin-to-skin care as compared to baseline. At T1, infants also had significantly reduced heart rate (p = 0.002) and respiratory rate (p < 0.0001) and increased systolic blood pressure (p = 0.033) during skin-to-skin care. At both T1 and T2, infant cortisol remained stable and unchanged from pre-skin-to-skin care to during skin-to-skin care (p = 0.096 and p = 0.356, respectively), and significantly increased from during skin-to-skin care to post-skin-to-skin care (p = 0.001 and p = 0.023, respectively). Exploratory analysis revealed differences in cortisol reactivity for infants with higher baseline cortisol (> 0.3 μg/dL) versus lower (≤ 0.3 μg/dL) prior to skin-to-skin care. Infants with higher baseline cortisol at T2 experienced significantly reduced cortisol during skin-to-skin care (p = 0.025). No significant differences in demographics or baseline variables were found between infants in either group.

CONCLUSIONS

Skin-to-skin care is a low-cost, low-risk intervention that promotes comfort and supports physiologic stability in infants before and after neonatal cardiac surgery.

Glucocorticoid Receptor Polymorphisms in Children Undergoing Congenital Heart Surgery with Cardiopulmonary Bypass

We conducted a candidate gene association study to test the hypothesis that different gene polymorphisms will be associated with corticosteroid responsiveness and study outcomes among children undergoing congenital heart surgery. This is a prospective observational cohort study at a large, tertiary pediatric cardiac center on children undergoing corrective or palliative congenital heart surgery. A total of 83 children were enrolled. DNA was isolated for three polymorphisms of interest namely N363 (rs56149945) and 9β (rs6198) associated with increased sensitivity to corticosteroids and Bcl I (rs41423247) associated with decreased sensitivity to corticosteroids. Duration of inotropic use, low cardiac output scores (LCOS), and vasoactive inotrope scores were examined in relation to these three polymorphisms. Using Kaplan-Meier analysis, heterozygous individuals showed longer transcriptional intermediary factor (TIF) compared with wild type for N363 polymorphism ( p  = 0.05). In multivariable Cox regression, heterozygous alleles for 9β polymorphism showed significantly shorter TIF compared with wild type (hazard ratio = 2.04 [1.08-3.87], p  = 0.03). The relationship between lower LCOS scores and alleles groups was significant for 9β heterozygous polymorphism only (1.5 [1-2.2], p  = 0.01) in comparison to wild type and homozygous. The presence of heterozygote alleles for the increased corticosteroid sensitivity is associated with longer TIF compared with wild type. Conversely, the presence of heterozygous alleles for the decreased sensitivity to corticosteroids is associated with shorter TIF compared with wild type.

Pre-operative neutrophil-lymphocyte ratio predicts low cardiac output in children after cardiac surgery

Neutrophil-lymphocyte ratio has been associated with clinical outcomes in several groups of cardiac patients, including patients with coronary artery disease, cardiac failure, and cardiac transplant recipients. We hypothesised that pre- and/or post-operative haematological cell counts are associated with clinical outcomes in children undergoing cardiac surgery for CHD. We performed a post hoc analysis of data collected as part of a prospective observational cohort study (n = 83, data available n = 47) of children evaluated for glucocorticoid receptor levels after cardiac surgery (July 2015-January 2016). The association of neutrophil-lymphocyte ratio with low cardiac output syndrome, time to inotrope free, and vasoactive-inotropic score was examined using proportional odds analysis, cox regression, and linear regression models, respectively. A majority (80%) of patients were infants (median/interquartile range 4.1/0.2-7.6 months) with conotruncal (36%) and left-sided obstructed lesions (28%). Two patients required mechanical circulatory support and three died. Higher pre-operative neutrophil-lymphocyte ratio was associated with higher cumulative odds of severe/moderate versus mild low cardiac output on post-operative day 1 (odds ratio 2.86; 95% confidence interval 1.18-6.93; p = 0.02). Pre-operative neutrophil-lymphocyte ratio was not significantly associated with time to inotrope free or vasoactive-inotrope score. Post-operative neutrophil-lymphocyte ratio was also not associated with outcomes. In children after congenital heart surgery, higher pre-operative neutrophil-lymphocyte ratio was associated with a higher chance of low cardiac output in the early post-operative period. Pre-operative neutrophil-lymphocyte ratio maybe a useful prognostic marker in children undergoing congenital heart surgery.