Hepatic dysfunction after cardiac surgery in children

Density of aortopulmonary collaterals predicts in-hospital outcome in tetralogy of Fallot with pulmonary stenosis

OBJECTIVES

The aim of this study was to characterize the anatomy of aortopulmonary collateral (APC) arteries in tetralogy of Fallot and pulmonary stenosis and to determine whether APC density identified on preoperative multidetector cardiac computed tomography predicts in-hospital outcome.

METHODS

The retrospective single-centre study includes consecutive 135 (2015-2019) patients who underwent one-stage repair. Preoperative multidetector cardiac computed tomography, echocardiography and clinical outcomes were reviewed. The cut-off value of indexed total distal APC cross-sectional area (APC-CSA) was identified by receiver operating characteristic curve. Logistic regression was used for predictors analysis.

RESULTS

The median age and body weight were 19.7 (10.1-89.7) months and 10 (8.3-18) kg. A total of 337 APCs were detected with only one demonstrating severe stenosis. There was a strong and significant correlation between mean APC diameter per patient and age (r = 0.70, P < 0.001). APCs were imaged but mainly received no interventions. In-hospital mortality was similar between patients with high (indexed APC-CSA ≥3.0 mm2/m2) and low (<3.0 mm2/m2) APC density (P = 0.642). Significantly greater patients with high indexed APC-CSA experienced the in-hospital composite outcome of death, arrest, renal/hepatic injury, lactic acidosis or extracorporeal membrane oxygenation (P = 0.007). High APC density was associated with greater dosing (P = 0.008) and longer (P = 0.01) use of inotropic support, prolonged pleural drainage (P = 0.013), longer ventilation (P = 0.042), intensive care unit (P = 0.014) and hospital (P = 0.027) duration. No reintervention and death occurred in the follow-up with the median duration of 24.4 (11-36.6) months. Multivariable analysis showed the Nakata index (P = 0.05) and high APC density (P = 0.02) independently predicted the composite outcome.

CONCLUSIONS

In tetralogy of Fallot and pulmonary stenosis, APCs are likely to be dilated bronchial arteries. Preoperative multidetector cardiac computed tomography-derived APC density was as important as Nakata index in predicting the occurrence of in-hospital composite outcome. The APC-CSA of 3.0 mm2/m2 maybe considered as a threshold for risk stratification.

Survival and Mid-Term Neurologic Outcome After Extracorporeal Cardiopulmonary Resuscitation in Children

OBJECTIVES

Extracorporeal cardiopulmonary resuscitation in children with refractory cardiac arrest has been shown to improve survival, however, risk factors associated with mortality and neurologic impairments are not well defined. We analyzed our recent institutional experience with pediatric extracorporeal cardiopulmonary resuscitation to identify variables associated with survival and neurocognitive outcome.

DESIGN

Retrospective observational study.

SETTING

Pediatric cardiology and congenital heart surgery departments of a tertiary referral heart center.

PATIENTS

Seventy-two consecutive children (median age, 0.3 yr [0.0-1.9 yr]) who underwent extracorporeal cardiopulmonary resuscitation at our institution during the study period from 2005 to 2016.

INTERVENTIONS

Not applicable.

MEASUREMENTS AND MAIN RESULTS

Median duration of resuscitation was 60 minutes (42-80 min) and median extracorporeal support duration was 5.4 days (2.2-7.9 d). Forty-three (59.7%) extracorporeal cardiopulmonary resuscitation events occurred during off-hours, however, neither duration of resuscitation (65 min [49-89 min] vs 51 min [35-80 min]; p = 0.16) nor survival (34.9% vs 37.9%; p = 0.81) differed significantly compared to working hours. Congenital heart disease was present in 84.7% of the patients. Survival to hospital discharge was 36.1%; younger age, higher lactate levels after resuscitation, acute kidney injury, renal replacement therapy, hepatic injury, and complexity of prior cardiothoracic surgical procedures were significantly associated with mortality. At mid-term follow-up (median, 4.1 yr [3.7-6.1 yr]), 22 patients (84.6% of discharge survivors) were still alive with 77.3% having a favorable neurologic outcome. High lactate levels, arrest location other than ICU, and requirement for renal replacement therapy were associated with unfavorable neurologic outcome. Interestingly, longer duration of resuscitation did not negatively impact survival or neurologic outcome.

CONCLUSIONS

Extracorporeal cardiopulmonary resuscitation is a valuable tool for the treatment of children with refractory cardiac arrest and a favorable neurologic outcome can be achieved in the majority of survivors even after prolonged resuscitation. Mortality after extracorporeal cardiopulmonary resuscitation in postcardiac surgery children is associated with procedural complexity.

Hyperbilirubinaemia after cardiac surgery: the point of no return

Aims

The occurrence of hyperbilirubinaemia after heart surgery using cardiopulmonary bypass or post‐operative heart failure is fairly common. We investigated the incidence, predictive value, and post‐operative outcome of hyperbilirubinaemia after cardiac surgery in an effort to identify potential risk factors and significance on clinical outcome.

Methods and results

Between 2006 and 2016, 1272 (10.1%) out of 12 556 patients developed hyperbilirubinaemia, defined as bilirubin concentration >3 mg/dL, during post‐operative course at our institution. All patients who were operated using cardiopulmonary bypass were included. Hepatic dysfunction was diagnosed preoperatively in 200 patients (15.7%), whereas mean model of end‐stage liver disease score was 11.22 ± 4.99. Early mortality was 17.4% with age [hazard ratio (HR) 1.019, 95% confidence interval (CI) 1.008–1.029; P = 0.001], diabetes (HR 1.115, CI 1.020–1.220; P = 0.017), and emergent procedures (HR 1.315, CI 1.012–1.710) as multivariate predictors. Post‐operative predictors were low‐output syndrome (HR 3.193, 95% CI 2.495–4.086; P < 0.001), blood transfusion (HR 1.0, CI 1.0–1.0; P < 0.001), and time to peak bilirubin (HR 1.1, CI 1.0–1.1; P < 0.001). We found an increased correlation with mortality at 3.5 post‐operative day as well as an optimal cut‐off value for bilirubin of 5.35 mg/dL. A maximum bilirubin of 25.5 mg/dL was associated with 99% mortality. Survival analysis showed significantly decreased survival for patients who developed late, rather than early, hyperbilirubinaemia.

Conclusions

Post‐operative hyperbilirubinaemia is a prevalent threat after cardiopulmonary bypass, associated with high early mortality. The timing and amount of peak bilirubin concentration are linked to the underlying pathology and are predictors of post‐operative outcome. Patients with late development of steep hyperbilirubinaemia warrant meticulous post‐operative care optimizing cardiac and end organ functions before reaching the point of no return.

Selective visceral perfusion improves renal flow and hepatic function in neonatal aortic arch repair

OBJECTIVES

The aortic arch repair in the neonatal period is a complex procedure with significant morbidity. We define a useful double-perfusion technique and its effect on the function of abdominal organs in the postoperative course.

METHODS

Nine patients with double perfusion (Group 1) were compared with 14 patients with antegrade cerebral perfusion (Group 2). The objective was to discern the incidence of postoperative acute kidney injury and impaired hepatic function, as well as tissue perfusion and myocardial function parameters. Mechanical ventilation time, postoperative length of stay and 30-day mortality were measured. We excluded patients with extracorporeal membrane oxygenation, early mortality (<72 h) and preoperative renal or hepatic insufficiency.

RESULTS

Nine (39%) patients developed postoperative acute kidney injury, with 22% (n = 2) in Group 1 and 50% (n = 7) in Group 2 (P = 0.183). A higher urine output was observed during the first 24 h for Group 1 (P = 0.032). Eleven patients developed impaired hepatic function in the immediate postoperative period: 2 (18.2%) in Group 1 and 9 (81.8%) in Group 2 (P = 0.04). The international normalized ratio (P = 0.006-0.031) and prothrombin time (P = 0.007-P = 0.016) were significantly lower in the double-perfusion group during the first 72 h. Significant difference was observed in lactate levels in the first 72 h (P = 0.001-0.009). There was no postoperative mortality in either group.

CONCLUSIONS

Selective visceral perfusion is a safe procedure that provides a better urine output, hepatic function and tissue perfusion. This technique allows for the repair of complex aortic arch anomalies in neonates without deep hypothermic circulatory arrest.

Prognostic Impacts of Increases in Amino Transaminases Following Coronary Artery Bypass Grafting on Mortality

OBJECTIVE

To evaluate the prognostic impacts of postoperative increases in serum amino transaminases on 1-year mortality in patients who underwent coronary artery bypass graft.

DESIGN

A retrospective analysis.

SETTING

A tertiary care university hospital.

PARTICIPANTS

A total of 1,950 patients who underwent coronary artery bypass graft.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Aspartate amino transaminase and alanine amino transaminase ratios were calculated as the ratio between the peak aspartate amino transaminase and alanine amino transaminase within the first 5 post-operative days and their respective upper limit of normal values. A ratio of 2.0 was seen to be the minimum for which a difference in 1-year mortality could be detected in univariate analysis, when considering simultaneously both aspartate amino transaminase and alanine amino transaminase ratios. Multivariable analysis showed an association between an aspartate amino transaminase ratio > 2.0 and increased 1-year mortality (hazard ratio [HR] 2.68, 95% confidence interval [CI] 1.42-5.05, P = 0.002), and also between both an aspartate amino transaminase and alanine amino transaminase ratio > 2.0 and increased 1-year mortality (HR 3.90, 95% CI 1.87-8.14, P < 0.001). However, increases in alanine amino transaminase only above the upper limit of normal were not associated with increased 1-year mortality.

CONCLUSIONS

Postoperative increases in aspartate amino transaminase only and increases in both aspartate amino transaminase and alanine amino transaminase greater than twice the upper limit of normal were associated with increased 1-year mortality in patients undergoing coronary artery bypass graft.

Severe Direct Hyperbilirubinemia as a Consequence of Right Heart Failure in Congenital Heart Disease

Adult literature documents increased cholestasis in right heart failure yet is poorly documented in the pediatric population. We describe three infants with congenital heart disease who developed significantly elevated direct bilirubin levels of 43, 23, and 12 mg/dL, respectively, in the absence of hepatic dysfunction. The common hemodynamic pathophysiology in these infants is right heart dysfunction with moderate to severe tricuspid regurgitation in the setting of low perfusion state. Right heart dysfunction in infants can result in severe conjugated bilirubin, likely as a consequence of venous congestion and can be used as an indirect marker of right heart dynamics.

Baicalein Reduces Liver Injury Induced by Myocardial Ischemia and Reperfusion

Baicalein is a component of the root of Scutellaria baicalensis Georgi, which has traditionally been used to treat liver disease in China. In the present study, we investigated baicalein' ability to reduce the liver injury induced by myocardial ischemia and reperfusion (I/R). Myocardial I/R was induced in this experiment by a 40[Formula: see text]min occlusion of the left anterior descending coronary artery and a 3[Formula: see text]h reperfusion in rats. The induced myocardial I/R significantly increased the serum levels of aspartate transaminase (AST) and alanine transaminase (ALT), indicating the presence of liver injury. Hepatic apoptosis was significantly increased. The serum levels of tumor necrosis factor-[Formula: see text] (TNF-[Formula: see text]), interleukin-1[Formula: see text] (IL-1[Formula: see text]), and interleukin-6 (IL-6) were significantly elevated, as was the TNF-[Formula: see text] level in the liver. Intravenous pretreatment with baicalein (3, 10, or 30[Formula: see text]mg/kg) 10[Formula: see text]min before myocardial I/R significantly reduced the serum level increase of AST and ALT, apoptosis in the liver, and the elevation of TNF-[Formula: see text], IL-1[Formula: see text], and IL-6 levels. Moreover, baicalein increased Bcl-2 and decreased Bax in the liver. Phosphorylation of the prosurvival kinases, including Akt and extracellular signal-regulated kinases 1 and 2 (ERK1/2), was also increased. In conclusion, we found that baicalein can reduce the liver injury induced by myocardial I/R. The underlying mechanisms are likely related to the inhibition of the extrinsic and intrinsic apoptotic pathways, possibly via the inhibition of TNF-[Formula: see text] production, the modulation of Bcl-2 and Bax, and the activation of Akt and ERK1/2. Our findings may provide a rationale for the application of baicalein or traditional Chinese medicine containing large amounts of baicalein to prevent liver injury in acute myocardial infarction and cardiac surgery.

Liver Function Tests Following Open Cardiac Surgery

Introduction: The cardiopulmonary bypass may have multiple systemic effects on the body organs as liver. This prospective study was planned to explore further the incidence and significance of this change.

Methods: Two hundred patients with coronary artery bypass grafting (CABG), were randomly selected for the study. Total and indirect bilirubin, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase were measured preoperatively and at 24, 48 and 72 hours, following coronary artery bypass grafting. Postoperative value of the liver function tests with respect to hypothermia or hypotension were compared by one way analysis of variance for repeated measure and compared with t test. Patient’s characteristics with bilirubin value (≤1.5 mg or >1.5 mg) were compared with t test.

Results: A significant increase of total bilirubin, aspartate aminotransferase, and alkaline phosphatase were noted in the third postoperative day. Significant relation was seen between hypotension and alkaline phosphatase, and aspartate aminotransferase change but hypothermia had not affected alanine aminotransferase, total bilirubin and indirect bilirubin change. Pump time, alanine aminotransferase in third postoperative day and direct bilirubin in first and second day of postoperative period had significant relation with pre and post-operative bilirubin change.

Conclusion: Transient but not permanent alterations of hepatic enzymes after coronary artery bypass grafting presumably attributed to the decreased hepatic flow, hypoxia, or pump-induced inflammation.

Ultrasonographic evaluation of abdominal organs after cardiac surgery

BACKGROUND

Disturbances of the hepatosplanchnic region may occur after cardiac operations. Experimental studies have implicated impairment of splanchnic blood supply in major abdominal organ dysfunction after cardiopulmonary bypass (CPB). We investigated the impact of the cardiac operation and CPB on liver, kidney, and renal perfusion and function by means of ultrasonography and biochemical indices in a selected group of cardiac surgery patients.

MATERIALS AND METHODS

Seventy five patients scheduled for a major cardiac operation were prospectively included in the study. Criteria for selection were moderate or good left ventricular ejection fraction and absence of previous hepatic or renal impairment. Ultrasound examination of the hepatic and renal vasculature and examination of biochemical parameters were performed on the day preceding the operation (T0), on the first postoperative day (T1), and on the seventh postoperative day (T2).

RESULTS

Portal vein velocity and flow volume increased significantly, whereas hepatic artery velocity and flow volume decreased at T1 in comparison with T0. Hepatic vein indices remained unaffected throughout the observation period. Renal artery velocity and flow decreased, whereas renal pulsatility index and renal resistive index increased at T1 as compared with T0. Aspartate aminotransferase and alanine aminotransferase values were increased as compared with baseline values 24 h postoperatively. All parameters displayed a trend to approach preoperative levels at T2. Strong negative correlations between alanine aminotransferase values at T1 and hepatic artery velocity and flow volume at the same time point were also demonstrated (R = 0.638, P < 0.001 and r = 0.662, P < 0.001, respectively).

CONCLUSIONS

The increase in portal vein flow and velocity and the decrease in hepatic artery flow and velocity in the period after CPB might be attributed to the hypothermic bypass technique and the hepatic arterial buffer response, respectively. The decrease in renal blood flow and velocity and the parallel increase in Doppler renal pulsatility index and renal resistive index could be considered as markers of kidney hypoperfusion and intrarenal vasoconstriction. Maintaining a high index of suspicion for the early diagnosis of noncardiac complications in the period after CPB and institution of supportive care in case of compromised splanchnic perfusion are warranted.

A composite outcome for neonatal cardiac surgery research

OBJECTIVE

The objective of this study was to determine whether a composite outcome, derived of objective signs of inadequate cardiac output, would be associated with other important measures of outcomes and therefore be an appropriate end point for clinical trials in neonatal cardiac surgery.

METHODS

Neonates (n = 76) undergoing cardiac operations requiring cardiopulmonary bypass were prospectively enrolled. Patients were defined to have met the composite outcome if they had any of the following events before hospital discharge: death, the use of mechanical circulatory support, cardiac arrest requiring chest compressions, hepatic injury (2 times the upper limit of normal for aspartate aminotransferase or alanine aminotransferase), renal injury (creatinine >1.5 mg/dL), or lactic acidosis (an increasing lactate >5 mmol/L in the postoperative period). Associations between the composite outcome and the duration of mechanical ventilation, intensive care unit stay, hospital stay, and total hospital charges were determined.

RESULTS

The median age at the time of surgery was 7 days, and the median weight was 3.2 kg. The composite outcome was met in 39% of patients (30/76). Patients who met the composite outcome compared with those who did not had a longer duration of mechanical ventilation (4.9 vs 2.9 days, P < .01), intensive care unit stay (8.8 vs 5.7 days, P < .01), hospital stay (23 vs 12 days, P < .01), and increased hospital charges ($258,000 vs $170,000, P < .01). In linear regression analysis, controlling for surgical complexity, these differences remained significant (R(2) = 0.29-0.42, P < .01).

CONCLUSIONS

The composite outcome is highly associated with important early operative outcomes and may serve as a useful end point for future clinical research in neonates undergoing cardiac operations.

Gastrointestinal complications in critically ill patients: what differs between adults and children?

PURPOSE OF REVIEW

The objective of this review has been to analyse and compare the causes, incidence, severity and treatment of gastrointestinal complications in critically ill children and adults.

RECENT FINDINGS

The incidence of gastrointestinal complications in critically ill patients published in the literature is very variable owing to the absence of unified diagnostic criteria both in children and adults. The incidence of gastrointestinal complications related to nutrition appears to be lower in children than in adults, and there are no differences in the incidence of gastrointestinal complications between gastric and transpyloric nutrition except with respect to the volume of gastric residues. The most important risk factors for digestive tract complications are shock and the administration of drugs (catecholamines, sedatives and muscle relaxants). Altered gastrointestinal motility is the principal mechanism underlying an excessive gastric residue, abdominal distension and constipation.

SUMMARY

Gastrointestinal complications limit the efficacy of enteral nutrition in the critically ill patient and can affect morbidity and mortality. Consensus must be reached on the definition of the criteria of excessive gastric residues, constipation and diarrhoea, and studies must be performed that evaluate the efficacy of prokinetic agents on altered gastrointestinal motility and the effects of diet and laxatives on constipation in the critically ill adult and child.

Application of a complication screening method to congenital heart surgery admissions: a preliminary report

There have been comprehensive screening methods developed to identify unwanted inpatient events. A comprehensive assessment of complication diagnoses during congenital heart surgery admissions has not been performed. We examined the frequency of complications identified by a complication screening method and their relationship to patient characteristics among congenital heart surgery admissions. Data were obtained from the Healthcare Cost and Utilization Project Kids' Inpatient Database 2000. Among congenital heart surgery admissions, age < or =20 years, we identified International Classification of Disease, 9th Revision, Clinical Modification (ICD-9-CM) codes indicating complication. Complication diagnoses were categorized as related to drug/biologic, procedures, devices, implants and grafts, and radiation. We used the Risk Adjustment for Congenital Heart Surgery risk categories (1-6) to examine the association between case complexity and complications. Multivariate analyses estimated the odds for a complication diagnosis by patient characteristics, including age, prematurity, chromosomal anomalies, noncardiac structural anomalies, and surgical risk category. Among 12,717 cases, 4014 (32%) had at least 1 complication diagnosis code. Procedure-related complication diagnoses represented 75% of complication diagnoses; device, implant, or graft represented 21%; drug/biologic represented 4% and radiation represented 0%. Multivariate analyses demonstrated that higher surgical case complexity and older age had a greater risk for a complication diagnosis: Risk Category 2, odds ratio (OR) 1.8; 3 OR 2.9; 4 OR 2.9; 5 OR 5.0; 6 OR 4.1, relative to category 1, all p < 0.01; age > or =12 years, OR 1.3, p < 0.001; <1 year OR 1.1, p = 0.31. Premature cases had decreased odds OR 0.4, p < 0.001. This complication screening method indicates that unwanted patient events occur frequently during congenital heart surgery admissions. Children undergoing complex congenital heart surgery are at greatest risk for these unwanted events. Further study of these events is needed to determine their preventability and severity.

Hepatic involvement in perinatal asphyxia

BACKGROUND

The pathogenetic mechanisms of hepatic injury in perinatal asphyxia (PNA) are similar to those in ischemic hepatitis, yet liver involvement is currently not considered a component of multi-organ failure in PNA.

METHODS

A retrospective study was done on 56 newborns with PNA. Hepatocyte injury was diagnosed based on elevated serum alanine transaminase level (>100 U/L, twice upper normal) with subsequent normalization.

RESULTS AND CONCLUSIONS

Twenty-two of the patients had hepatocyte injury. Fetal distress, thrombocytopenia, convulsions, pathologic findings on imaging of the central nervous system, and a high rate of intrauterine growth retardation were the factors significantly associated with hepatocyte injury. This damage was also associated with high mortality.

Complications and Risk Factors for Mortality During Congenital Heart Surgery Admissions

BACKGROUND

We have previously reported a high rate (32%) of complications among congenital heart surgery admissions. The association among reported complications and other risk factors for mortality during congenital heart surgery admissions has not been assessed.

METHODS

We identified congenital heart surgery admissions, ages less than 18 years, within the Kids' Inpatient Database 2000, and applied a complication screening method using "International Classification of Disease, 9th Revision, Clinical Modification." Complication diagnoses were classified into four categories, complications due to the following: (1) drugs; (2) procedures; (3) devices, implants, and grafts; and (4) radiation. We examined the independent effect of a complication diagnosis code and complication subcategory on mortality using generalized estimating equations controlling for case-mix using the Risk Adjustment for Congenital Heart Surgery (RACHS-1) method, as well as other previously reported predictors for mortality.

RESULTS

Among the 10,032 congenital heart surgical admissions, 32% had at least one complication diagnosis. Seventy-eight percent of complication diagnoses were procedure related, 18% device, implant, or graft related, and 4% drug related. There were no radiation complications identified. After adjusting for case-mix, gender, race, insurance, and hospital surgical volume, admissions with a complication diagnosis had a substantially greater odds of death compared with admissions without a complication (odds ratio [OR] 2.4, p < 0.001). Among complication subcategories, procedure (OR 2.3, p < 0.001), and device, implant, or graft (OR 2.7, p < 0.001) related complications contributed to higher death risk.

CONCLUSIONS

Complication diagnoses occur frequently during congenital heart surgery admissions and are associated with an increased risk of death even after controlling for other known mortality risk factors. Identification of complication diagnoses is an important first step. Subsequent efforts must further examine these events to determine their degree of preventability and develop strategies to reduce them. Such an effort may reduce death in this vulnerable population. This study represents preliminary work in an effort to improve outcomes in this complex patient population.