Vasopressor magnitude predicts poor outcome in adults with congenital heart disease after cardiac surgery.

BACKGROUND: High levels of vasoactive inotrope support (VIS) after congenital heart surgery are predictive of morbidity in pediatric patients. We sought to discern if this relationship applies to adults with congenital heart disease (ACHD). METHODS: We retrospectively studied adult patients (≥18 years old) admitted to the intensive care unit after cardiac surgery for congenital heart disease from 2002 to 2013 at Mayo Clinic. Vasoactive medication dose values within 96 hours of admission were examined to determine the relationship between VIS score and poor outcome of early mortality, early morbidity, or complication related morbidity. RESULTS: Overall, 1040 ACHD patients had cardiac surgery during the study time frame; 243 (23.4%) met study inclusion criteria. Sixty-two patients (25%), experienced composite poor outcome [including eight deaths within 90 days of hospital discharge (3%)]. Thirty-eight patients (15%) endured complication related early morbidity. The maximum VIS (maxVIS) score area under the curve was 0.92 (95% CI: 0.86-0.98) for in-hospital mortality; and 0.82 (95% CI: 0.76-0.89) for combined poor clinical outcome. On univariate analysis, maxVIS score ≥3 was predictive of composite adverse outcome (OR: 14.2, 95% CI: 7.2-28.2; P < 0.001), prolonged ICU LOS ICU LOS (OR: 19.2; 95% CI: 8.7-42.1; P < 0.0001), prolonged mechanical ventilation (OR: 13.6; 95% CI: 4.4-41.8; P < 0.0001) and complication related morbidity (OR: 7.3; 95% CI: 3.4-15.5; P < 0.0001). CONCLUSIONS: MaxVIS score strongly predicted adverse outcomes and can be used as a risk prediction tool to facilitate early intervention that may improve outcome and assist with clinical decision making for ACHD patients after cardiac surgery.

Total and free cortisol responses and their relation to outcomes after cardiopulmonary bypass in infants.

BACKGROUND: Hypothalamic-pituitary-adrenal (HPA) axis dysfunction may be partially responsible for the hemodynamic instability experienced by infants after cardiopulmonary bypass (CPB). We report the full spectrum of the HPA response surrounding CPB for infant congenital cardiac surgery. METHODS: We enrolled 84 infants who received 1 mg/kg of dexamethasone before initiation of CPB. Total cortisol (TC), free cortisol (FC), adrenocorticotropic hormone (ACTH), and corticosteroid-binding globulin (CBG) were measured at 3 time points: immediately before CPB (TP1), on intensive care unit arrival (TP2), and at 24 hours after surgery (TP3). A 1-µg ACTH stimulation test was performed at each time point to evaluate adrenal responsiveness. RESULTS: Sixty-eight infants completed all study procedures. Levels of TC, FC, CBG, and ACTH decreased significantly between the preoperative and 24-hour postoperative measurements. There were no significant associations between preoperative FC responses and clinical outcomes after adjusting for weight and Risk-Adjusted Scores for Congenital Heart Surgery. Infants with subnormal TC responses to ACTH stimulation (<9 µg/dL) at TP2 had greater fluid requirements (P < .001) and greater chest tube output (P < .001) during the first 24 hours, as well as longer length of stay (LOS) (P = .007). Except for LOS, these differences persisted for infants with subnormal stimulation tests at TP3. CONCLUSIONS: We observed a significant decline in all aspects of the HPA axis throughout the first 24 hours after infant CPB. TC and FC levels were not associated with clinical outcomes. Subnormal (Δ <9 µg/dL) TC response to cosyntropin stimulation during the postoperative period was associated with increased fluid resuscitation and greater LOS.

Assessing health disparities in children using a modified housing-related socioeconomic status measure: a cross-sectional study.

OBJECTIVES: Socioeconomic status (SES) is a well-established risk factor for many health outcomes. Recently, we developed an SES measure based on 4 housing-related characteristics (termed HOUSES) and demonstrated its ability to assess health disparities. In this study, we aimed to evaluate whether fewer housing-related characteristics could be used to provide a similar representation of SES. STUDY SETTING AND PARTICIPANTS: We performed a cross-sectional study using parents/guardians of children aged 1-17 years from 2 US Midwestern counties (n=728 in Olmsted County, Minnesota, and n=701 in Jackson County, Missouri). PRIMARY AND SECONDARY OUTCOME MEASURES: For each participant, housing-related characteristics used in the formulation of HOUSES (assessed housing value, square footage, number of bedrooms and number of bathrooms) were obtained from the local government assessor's offices, and additional SES measures and health outcomes with known associations to SES (obesity, low birth weight and smoking exposure) were collected from a telephone survey. Housing characteristics with the greatest contribution for predicting the health outcomes were added to formulate a modified HOUSES index. RESULTS: Among the 4 housing characteristics used in the original HOUSES, the strongest contributions for predicting health outcomes were observed from assessed housing value and square footage (combined contribution ranged between 89% and 96%). Based on this observation, these 2 were used to calculate a modified HOUSES index. Correlation between modified HOUSES and other SES measures was comparable to the original HOUSES for both locations. Consistent with the original HOUSES formula, the strongest association with modified HOUSES was observed with smoking exposure (OR=0.24 with 95% CI 0.11 to 0.49 for comparing participants in highest HOUSES vs lowest group; overall p<0.001). CONCLUSIONS: The modified HOUSES requires only 2 readily available housing characteristics thereby improving the feasibility of using this index as a proxy for SES in multiple communities, especially in the US Midwestern region.

Duration and magnitude of vasopressor support predicts poor outcome after infant cardiac operations.

BACKGROUND: The vasoactive inotrope score (VIS) is a sum of the total vasopressor dose at a single point in time. Incorporating duration and magnitude of vasopressor requirements during the postcardiac surgical period could improve VIS sensitivity for predicting poor outcome. METHODS: This is a retrospective review of 244 infants (aged ≤365 days) who underwent cardiopulmonary bypass during congenital cardiac operations from 2002 to 2011. The VIS was calculated hourly for the first 72 hours. Poor outcome was defined as prolonged mechanical ventilation (≥6 days) or intensive care length of stay (≥12 days). First, the association between the maximum VIS (maxVIS) in the first 48 postoperative hours and poor outcome was confirmed for our study population. Next, postoperative intervals and VIS values that were significantly associated with poor outcome were identified and incorporated into a formula, termed the VISindex, which was compared with the traditional maxVIS. RESULTS: The VISindex demonstrated improved sensitivity for predicting prolonged mechanical ventilation (VISindex: area under the curve [AUC], 0.85; 95% confidence interval [CI], 0.79 to 0.90; maxVIS: AUC, 0.80; 95% CI, 0.75 to 0.86) and intensive care unit length of stay (VISindex: AUC, 0.84; 95% CI, 0.79 to 0.89; maxVIS: AUC, 0.77; 95% CI, 0.71 to 0.83) after cardiac operations in infants. CONCLUSIONS: Incorporating magnitude and duration of postoperative vasopressor support into the VIS improves its sensitivity for predicting poor outcome.

Dexamethasone levels predict cortisol response after infant cardiopulmonary bypass.

OBJECTIVES: We sought to evaluate whether there is variability in blood dexamethasone levels after a standard 1 mg/kg dose of dexamethasone administered before infant cardiopulmonary bypass. We hypothesized that postoperative dexamethasone drug levels are highly variable, and that the infant stress response is related inversely to the amount of dexamethasone measured in the blood. METHODS: Thirty-two infants (age, ≤365 days) received 1 mg/kg of dexamethasone before cardiopulmonary bypass (CPB) initiation. Blood was analyzed for cortisol, adrenocorticotropin, and interleukin (IL)-6, IL-8, and IL-10 levels after anesthesia induction, after CPB, after intensive care unit (ICU) arrival, and 4, 8, 12, and 24 hours after surgery. Patients were grouped as high dexamethasone (≥15 µg/dL) or low dexamethasone (<15 µg/dL) based on their level at ICU arrival. RESULTS: Dexamethasone levels varied significantly between the high (n = 22) and low (n = 10) dexamethasone groups throughout the entire postoperative course and were correlated highly with cortisol response. Patients with high dexamethasone levels had postoperative cortisol levels that were lower than their pre-CPB baseline cortisol levels. Cortisol levels remained low throughout the first 24 postoperative hours even after dexamethasone levels neared zero. There were no significant differences between groups in the duration of mechanical ventilation or ICU length of stay. CONCLUSIONS: Dexamethasone levels are highly variable at ICU arrival, despite standardized 1 mg/kg dosing before CPB initiation.

Mechanical circulatory support in patients with heart failure secondary to transposition of the great arteries.

Advances in palliation of congenital heart disease have resulted in improved survival to adulthood. Many of these patients ultimately develop end-stage heart failure requiring left ventricular assist device implantation (LVAD). However, morphologic differences in the systemic ventricle of these patients require careful attention to cannula placement. We report on the evolution of our surgical technique for implanting LVADs in 3 patients with transposition of the great arteries and congenitally corrected transposition of the great arteries. Applying standard LV cannulation techniques to the systemic ventricle led us too anteriorly in our first patient, creating obstruction by the moderator band. Subsequent use of epicardial and transesophageal echocardiography allowed for intraoperative localization of the intracardiac muscular structures to identify the optimal cannulation site. The acute angle of the inflow cannula on the DeBakey LVAD (MicroMed Technology, Houston, TX) required flipping the device 180°. The HeartMate II device (Thoratec, Pleasanton, CA) could be shifted towards the midline. One patient underwent successful transplant and 2 are home waiting for a donor organ. We conclude from our experience that LVAD surgery can be safely performed in patients with congenital heart disease when implanted under echocardiographic guidance.

Postoperative coagulopathy in a pediatric patient after exposure to bovine topical thrombin.

Severe postoperative coagulopathy developed in a child with congenital heart disease due to a factor V inhibitor from repetitive exposure to bovine topical thrombin. This case report alerts pediatric providers to consider these inhibitors when postoperative coagulopathy occurs. Potential treatment options are reviewed.