A review of the natriuretic hormone system's diagnostic and therapeutic potential in critically ill children

Predictive value of a nomogram model for adverse outcomes in very low birth weight infants with patent ductus arteriosus: A prospective study

Objective

To establish a nomogram model incorporating markers of echocardiography and N-terminal pro brain natriuretic peptide (NT-proBNP) for predicting adverse outcomes of patent ductus arteriosus (PDAao) in very low birth weight infants and to evaluate the predictive values of the model.

Methods

A prospective study was conducted for very low birth weight infants who were admitted from May 2019 to September 2020. An echocardiogram and blood NT-proBNP test were carried out in the first 48 h after birth, and the arterial duct remained open in all patients. Other data collected included clinical symptoms and infant characteristics. A nomogram model was established to predict the risk of PDAao (including severe BPD, IVH, NEC or death). Internal verifications were performed for the nomogram, and the discrimination and calibration of the model were evaluated by the C-index and calibration curve.

Results

Eighty-two infants were enrolled and divided into an adverse outcome (AO) group and normal outcome (NO) group with 41 patients in each group. PDA diameter, PDA maximum flow velocity, left atrium diameter/aortic diameter (LA/AO) ratio and NT-proBNP level were independent risk factors for PDAao and were included in the nomogram model. The model presented good discrimination with a C-index of 0.917 (95% CI 0.859-0.975). The calibration curves in showed high consistency and indicated good Correspondence: between the event incidence predicted by the nomogram model and the true incidence of PDAao.

Conclusion

The nomogram model incorporating the PDA diameter, PDA maximum flow velocity, LA/AO ratio and NT-proBNP level in the first 48 h could early predict the later occurrence of PDAao in very low birth weight infants.

Impact of urine osmolality/urine sodium on the timing of diuretic phase and non-invasive ventilation support: Differences from late preterm to term neonates

BACKGROUND

Extracellular fluid retained in the lungs lead to respiratory distress in both late preterm (LP) and term neonates. The relationship between urine parameters toward the diuresis and the duration of ventilation postnatally is unknown. To find the correlation between the diuretic phase with urine parameters in the first 4 days after birth and the duration of non-invasive ventilation (NIV).

METHODS

Serial measurements of urine osmolality (Uosm), urine sodium (U_Na), and urine output (U/O) in neonates were collected at 5 time periods (T1:0-12 postnatal hours, T2:12-24 postnatal hours, T3:24-48 postnatal hours, T4:48-72 postnatal hours, T5:72-96 postnatal hours) were recorded. The correlations were analyzed in late preterm and term neonates.

RESULTS

Ninety-seven neonates were included. Negative correlation between Uosm and U/O were observed. LP neonates (n=26) and term neonates (n=71) had differences with Uosm at T2, U_Na at T4, T5, and U/O at T2, T3. Factors of U/O < 1 ml/kg/hr at T1 (odds ratio (OR) = 20.0; 95% confidence interval (CI) 1.796-222.776; p = 0.015) or Uosm > 273 mOsm/L at T1 (OR = 9.0; 95% CI 1.031-78.574; p = 0.047) in LP neonates and U_Na > 26.5 mEq/L at T5 (OR = 23.625; 95% CI 2.683-79.276; p < 0.01) in term neonates were associated with prolonged NIV use (> 120 hours).

CONCLUSION

We speculate the significant correlation between Uosm/U_Na and the diuretic phase. The LP neonates acquire earlier diuretic phase than the term neonates. The Uosm/U_Na in the first few postnatal days had the correlation with the duration of NIV support.

Cardiac biomarkers and haemodynamically significant patent ductus arteriosus in preterm infants

Accurately defining haemodynamically significant patent ductus arteriosus (PDA) in preterm infants who are at risk of PDA related morbidities are active areas of neonatal research. Natriuretic peptides are cardiac hormones that respond to volume and pressure loading, with elevated plasma levels found in infants with PDA. In the preterm neonatal setting, studies to date have predominantly investigated the ability of these biomarkers to discriminate between infants with and without a PDA at various postnatal ages. Their clinical utility has therefore been exclusively evaluated as a method of triaging cases of suspected hsPDA to decrease the need for echocardiograms, and to monitor treatment response. Biomarkers are yet to be robustly investigated for their ability to predict important PDA associated morbidities. In this review, we examine the most recent literature to date on the use of biomarkers in the management of PDA.

Cardiac Biomarkers of Low Cardiac Output Syndrome in the Postoperative Period After Congenital Heart Disease Surgery in Children

INTRODUCTION AND OBJECTIVES

To assess the predictive value of atrial natriuretic peptide, β-type natriuretic peptide, copeptin, mid-regional pro-adrenomedullin (MR-proADM) and cardiac troponin I (cTn-I) as indicators of low cardiac output syndrome in children with congenital heart disease undergoing cardiopulmonary bypass (CPB).

METHODS

After corrective surgery for congenital heart disease under CPB, 117 children (aged 10 days to 180 months) were enrolled in a prospective observational pilot study during a 2-year period. The patients were classified according to whether they developed low cardiac output syndrome. Biomarker levels were measured at 2, 12, 24, and 48 hours post-CPB. The clinical data and outcome variables were analyzed by a multiple logistic regression model.

RESULTS

Thirty-three (29%) patients developed low cardiac output syndrome (group 1) and the remaining 84 (71%) patients were included in group 2. cTn-I levels >14 ng/mL at 2hours after CPB (OR, 4.05; 95%CI, 1.29-12.64; P=.016) and MR-proADM levels>1.5 nmol/L at 24hours following CPB (OR, 15.54; 95%CI, 4.41-54.71; P<.001) were independent predictors of low cardiac output syndrome.

CONCLUSIONS

Our results suggest that cTn-I at 2hours post-CPB is, by itself, an evident independent early predictor of low cardiac output syndrome. This predictive capacity is, moreover, reinforced when cTn-I is combined with MR-proADM levels at 24hours following CPB. These 2 cardiac biomarkers would aid in therapeutic decision-making in clinical practice and would also enable clinicians to modify the type of support to be used in the pediatric intensive care unit.

Early Elevated B-Type Natriuretic Peptide Levels are Associated with Cardiac Dysfunction and Poor Clinical Outcome in Pediatric Septic Patients

BACKGROUND

To determine the B-type natriuretic peptide (BNP) level in pediatric septic patients, and to investigate its association with cardiovascular dysfunction and clinical outcome.

METHODS

Pediatric patients with sepsis or septic shock were prospectively enrolled in our pediatric intensive care unit (PICU). On day 1 of admission, plasma BNP levels were measured at the time-point of echocardiography. Myocardial dysfunction was defined as left ventricular fractional shortening (FS) < 30%. Inotropic support was quantified by inotropic scores and disease severity was assessed by Pediatric Risk of Mortality (PRISM) III scores. Therafter, associations between BNP levels and clinical parameters were analyzed.

RESULTS

There were 94 patients (mean: 5.6 yr, range: 2 mo-17 yr) that were consecutively enrolled in this study. The median BNP level was 127 pg/ml (range: 5 to 4950 pg/ml). BNP levels were correlated with PRISM III (rho = 0.36, p = 0.001) and C-reactive protein level (r = 0.39, p = 0.001). The median BNP levels were not only higher in patients with septic shock (n = 34) than those with sepsis (n = 58) (213 vs. 54 pg/ml, p = 0.0004), but also higher in patients with myocardial dysfunction (n = 18) than those with preserved myocardial function (n = 66) (765 vs. 65 pg/ml, p < 0.001). We also found that BNP levels correlated negatively with FS (r = -0.56, p < 0.001) and positively with inotropic scores (r = 0.34, p = 0.04). Most importantly, the median BNP levels were higher in non-survivors (n = 13) than survivors (n = 81) (367 vs. 106 pg/ml, p = 0.003).

CONCLUSIONS

BNP levels are elevated in pediatric septic patients early in the disease course, and increased levels are associated with cardiovascular dysfunction and worse clinical outcome.

KEY WORDS

B-type natriuretic peptide; Cardiac function; Pediatric; Sepsis; Septic shock.

Serial N-terminal pro-brain natriuretic peptide measurement as a predictor of significant patent ductus arteriosus in preterm infants beyond the first week of life

The aim of the study was to assess the role of plasma N-terminal pro-brain natriuretic peptide (NT-proBNP) concentration as a predictor of patent ductus arteriosus (PDA) in very low birth weight infants beyond the first week of life. This was a prospective observational study; newborns with a birth weight < 1500 g were eligible for enrolment. Enrolled infants were screened by echocardiography on day seven of life for the presence of a PDA. This was paired with a blood sample for NT-proBNP level. Echocardiography and NT-proBNP levels were repeated at weekly intervals. The primary outcome was correlation between PDA and NT-proBNP level and between measurements of PDA significance and NT-proBNP. Sixty-nine neonates were enrolled following parental consent. The mean birth weight was 1119 ± 257 g and mean gestational age was 28.6 ± 2.6 weeks. Median NT-proBNP level on day seven was 11469 ng/l in infants with a PDA vs. 898 ng/l in infants without a PDA (p < 0.0001). There was a statistically significant correlation between PDA diameter and NT-proBNP level on day seven, day 14 and day 21.

CONCLUSION

NT-proBNP concentration is significantly increased in infants with a PDA and correlates well with PDA diameter in the first three weeks of life.

B-type natriuretic peptide levels predict outcomes in infants undergoing cardiac surgery in a lesion-dependent fashion

OBJECTIVE

B-type natriuretic peptide is used in the diagnosis, risk stratification, and management of adult patients with cardiac disease. However, its use in infants with congenital heart disease has been limited, particularly in the perioperative period. Our objective was to determine the alterations in perioperative B-type natriuretic peptide levels and their predictive value on postoperative outcomes, in infants undergoing congenital heart surgery.

METHODS

We prospectively enrolled 115 patients: 24 with univentricular heart disease undergoing a modified Norwood procedure, 11 with d-transposition of the great arteries, 55 with hemodynamically important left-to-right shunt, and 25 with tetralogy of Fallot undergoing primary repair. Clinical data and B-type natriuretic peptide samples were collected before and 2, 12, and 24 hours after cardiopulmonary bypass. Univariate analysis and multivariate linear regression analysis were performed.

RESULTS

The perioperative B-type natriuretic peptide levels were lesion specific. Patients with d-transposition of the great arteries and univentricular heart disease had high preoperative B-type natriuretic peptide levels that decreased postoperatively, and those with hemodynamically important left-to-right shunts and tetralogy of Fallot had lower preoperative levels that increased during the first 12 hours postoperatively. The patients with univentricular heart disease with an adverse outcome had a significantly greater 24-hour B-type natriuretic peptide level than those without (P < .05). Those with hemodynamically important left to right shunts and an adverse outcome had a greater 12-hour B-type natriuretic peptide level than those without (P < .05). A 12-hour postoperative/preoperative ratio greater than 45 was 100% sensitive and 82% specific for an adverse outcome in the patients with tetralogy of Fallot.

CONCLUSIONS

The perioperative changes in B-type natriuretic peptide levels and their ability to predict outcomes are lesion-specific. Characterization of these changes might be useful in caring for infants after congenital heart surgery.

Biomonitors of cardiac injury and performance: B-type natriuretic peptide and troponin as monitors of hemodynamics and oxygen transport balance

Serum biomarkers, such as B-type natriuretic peptide and troponin, are frequently measured in the cardiac intensive care unit. A review of the evidence supporting monitoring of these biomarkers is presented.

DESIGN

A search of MEDLINE, PubMed, and the Cochrane Database was conducted to find literature regarding the use of B-type natriuretic peptide and troponin in the cardiac intensive care setting. Adult and pediatric data were considered.

RESULTS AND CONCLUSION

Both B-type natriuretic peptide and troponin have demonstrated utility in the intensive care setting but there is no conclusive evidence at this time that either biomarker can be used to guide inpatient management of children with cardiac disease. Although B-type natriuretic peptide and troponin concentrations can alert clinicians to myocardial stress, injury, or hemodynamic alterations, the levels can also be elevated in a variety of clinical scenarios, including sepsis. Observational studies have demonstrated that perioperative measurement of these biomarkers can predict postoperative mortality and complications.

RECOMMENDATION AND LEVEL OF EVIDENCE

(class IIb, level of evidence B): The use of B-type natriuretic peptide and/or troponin measurements in the evaluation of hemodynamics and postoperative outcome in pediatric cardiac patients may be beneficial.

B-type natriuretic peptide: perioperative patterns in congenital heart disease

OBJECTIVE

B-type natriuretic peptide (BNP) has diagnostic, prognostic, and therapeutic roles in adults with heart failure. BNP levels in children undergoing surgical repair of congenital heart disease (CHD) were characterized broadly, and distinguishable subgroup patterns delineated.

DESIGN

Prospective, blinded, observational case series.

SETTING

Academic, tertiary care, free-standing pediatric hospital.

PATIENTS

Children with CHD; controls without cardiopulmonary disease. Interventions. None.

MEASUREMENTS

Preoperative cardiac medications/doses, CHD lesion types, perioperative BNP levels, intraoperative variables (lengths of surgery, bypass, cross-clamp), postoperative outcomes (lengths of ventilation, hospitalization, open chest; averages of inotropic support, central venous pressure, perfusion, urine output; death, low cardiac output syndrome (LCOS), cardiac arrest; readmission; and discharge medications).

RESULTS

Median BNP levels for 102 neonatal and non-neonatal controls were 27 and 7 pg/mL, respectively. Serial BNP measures from 105 patients undergoing CHD repair demonstrated a median postoperative peak at 12 hours. The median and interquartile postoperative 24-hour average BNP levels for neonates were 1506 (782-3784) pg/mL vs. 286 (169-578) pg/mL for non-neonates (P < 0.001). Postoperative BNP correlated with inotropic requirement, durations of open chest, ventilation, intensive care unit stay, and hospitalization (r = 0.33-0.65, all P < 0.001). Compared with biventricular CHD, Fontan palliations demonstrated lower postoperative BNP (median 150 vs. 306 pg/mL, P < 0.001), a 3-fold higher incidence of LCOS (P < 0.01), and longer length of hospitalization (median 6.0 vs. 4.5 days, P= 0.01).

CONCLUSIONS

Perioperative BNP correlates to severity of illness and lengths of therapy in the CHD population, overall. Substantial variation in BNP across time as well as within and between CHD lesions limits its practical utility as an isolated point-of-care measure. BNP commonly peaks 6-12 hours postoperatively, but the timing and magnitude of BNP elevation demonstrates notable age-dependency, peaking earlier and rising an order of magnitude higher in neonates. In spite of higher clinical acuity, non-neonatal univentricular CHD paradoxically demonstrates lower BNP levels compared with biventricular physiologies.

B-type natriuretic peptide utilization as an adjunct to management in a case of conjoined twins with pulmonary hypertension

This article reports a case of pulmonary hypertension in 37-week-gestational-age, pygopagus conjoined twins where B-type natriuretic peptide (BNP) was used as a cost-effective and important tool to aid effective management. Pulmonary hypertension in neonates is associated with high morbidity and mortality and multiplies the challenge of caring for conjoined twins. BNP is a peptide hormone secreted by cardiac ventricles that have undergone stress related to ventricular filling, volume overload, and pressure. BNP is commonly used in adults to assess heart failure, but its utility is less established in infants receiving neonatal intensive care. In this case, BNP testing was used as an adjunct to standard assessments for rapid diagnosis which was critical to expediting appropriate treatment management for these high-risk patients.

Vein of Galen arteriovenous malformation with PAPVR and use of serial B-type natriuretic peptide levels in the management: a case report and review of the literature

BACKGROUND

Arteriovenous malformation of the vein of Galen with partial anomalous pulmonary venous return can lead to a critically challenging condition associated with a high morbidity and mortality.

CASE REPORT

We report a case of a full term infant born with a vein of Gallen arteriovenous malformation complicated by partial anomalous pulmonary venous return and congestive heart failure where B-type natriuretic peptide was used as a vital tool in clinical assessment and treatment management.

CONCLUSIONS

Rapid diagnosis and treatment in infants with complex conditions such as this are imperative to expedite appropriate treatments, preventing long term negative outcome.

Early elevations in B-type natriuretic peptide levels are associated with poor clinical outcomes in pediatric acute lung injury

OBJECTIVES

To determine B-type natriuretic peptide (BNP) levels in infants and children with acute lung injury (ALI), and to investigate associations between BNP levels and clinical outcome.

DESIGN

Prospective observational study.

SUBJECTS

After informed consent, plasma was collected from 48 pediatric patients on day 1 of ALI.

METHODOLOGY

Plasma BNP levels were measured by immunoassay on day 1 of ALI in 48 pediatric patients. Associations between BNP levels and outcome were determined.

RESULTS

The mean PaO(2)/FiO(2) at the onset of ALI was 155 (+/-74) and BNP values ranged from 5 to 2,060 pg/ml with a mean of 109 (+/-311). BNP levels were inversely correlated with ventilator-free days (Spearman rho -0.30, P = 0.04), and positively correlated with exhaled tidal volume (Spearman rho 0.44, P = 0.02). BNP levels were higher in patients receiving inotropic support (n = 12) than patients not receiving inotropic support (n = 33, P = 0.02). BNP levels were correlated with PRISM III scores (Spearman rho 0.55, P < 0.001) and PELOD scores (Spearman rho 0.4, P = 0.006). Mortality for the cohort was 15%. BNP levels were higher in non-survivors (n = 7) than survivors (n = 41, P = 0.055).

CONCLUSIONS

BNP levels are elevated in children with ALI/ARDS early in the disease course, and increased levels are associated with worse clinical outcome.

The use of B-type natriuretic peptide in paediatric patients: a review of literature

OBJECTIVE

Plasma levels of brain natriuretic peptide (BNP) and its inactive fragment N-terminal pro-BNP are recognized as reliable markers of ventricular dysfunction in adults. We aimed to verify BNP applications in children.

METHODS

A review of the literature on this subject was carried out.

RESULTS

When dealing with paediatric patients, age and sex-related normal values must be considered. Higher BNP plasma levels are reported in children with chronic heart failure; they are related with the type of dysfunction and with prognosis. Moreover, increased BNP levels have been reported in asymptomatic children and adolescents pretreated with anthracyclines, who are at risk for ventricular dysfunction.

CONCLUSION

BNP and pro-BNP also seem to be effective markers of ventricular dysfunction in paediatric patients. Clinical use may be extended not only for the characterization of heart dysfunction, but also for monitoring asymptomatic patients at specific risk. To this purpose, wider application in clinical trials appears warranted.

Aminoterminal Pro B-Type Natriuretic Peptide (NT-proBNP) Levels for Monitoring Interventions in Paediatric Cardiac Patients with Stenotic Lesions

Background. Serum concentration of NT-proBNP correlates well with the severity of cardiac disease in adults. Few studies have been performed on the applicability of NT-proBNP for monitoring children with congenital heart disease. Objective. To assess the potential of NT-proBNP for monitoring the success of interventions in children with stenotic cardiac lesions. Methods. NT-proBNP was measured in 42 children aged 1 day to 17 years (y) before and 6 to 12 weeks after surgical or interventional correction of obstructive lesions of the heart. Comparison is made with the clinical status and echocardiographic data of the child. Results. NT-proBNP levels (median 280, range 10–263,000 pg/mL) were above the reference value in all but 6 patients (pts) prior to the intervention. Higher levels were found in more compromised patients. The 35 children with clinical improvement after the procedure showed a decline of their NT-proBNP level in all but 4 patients, whose levels remained unchanged. Five patients with unchanged gradients despite a therapeutic intervention also demonstrated unchanged NT-proBNP levels after the intervention. Thus, the success rate of the procedure correlated well to clinical and echocardiographic findings. Conclusion. NT-proBNP can be used to assess the efficiency of an intervention.

Transient ventricular dysfunction after an asphyxiation event: stress or hypoxia?

OBJECTIVE

This report of a pediatric patient with acute upper airway obstruction causing asphyxiation emphasizes the need to maintain clinical suspicion for acquired myocardial dysfunction, despite the presumed role of noncardiogenic causes for pulmonary edema after an acute upper airway obstruction.

DESIGN

Case report.

SETTING

A tertiary pediatric intensive care unit.

PATIENT

A 10-year-old girl with no significant medical history who developed flash pulmonary edema and acute myocardial dysfunction after an acute upper airway obstruction.

INTERVENTIONS

Serial echocardiograms, exercise stress test, and coronary angiography were performed. Serial pro-brain natriuretic peptide, troponins, and CK-MB levels were also followed.

RESULTS

Troponin level normalized approximately 7 days after the acute event. CK-MB and pro-brain natriuretic peptide levels decreased but had not completely normalized by time of discharge. The patient was discharged home 10 days after the event on an anticipated 6-month course of metoprolol without any signs or symptoms of cardiac dysfunction.

CONCLUSIONS

Myocardial dysfunction is rarely documented in children after an acute upper airway obstruction or an asphyxiation event. Pediatric intensivists and hospitalists should maintain a high degree of clinical suspicion and screen for possible myocardial dysfunction in the pediatric patient with an acute severe hypoxic event especially when accompanied by pulmonary edema. Prompt evaluation ensures appropriate support. Additionally, some role may exist for early adrenergic receptor blockade.

Plasma B-type natriuretic peptide monitoring to evaluate cardiovascular function prior to organ procurement in patients with brain death

BACKGROUND

The natriuretic peptide system plays an active role in the regulation of fluid balance and systemic vascular resistance. Assays of plasma concentrations of B-type natriuretic peptide (BNP) may have a diagnostic role in evaluating myocardial function. We present our experience with BNP monitoring to assess myocardial function after the proclamation of brain death in potential organ donors.

METHODS

After the proclamation of brain death and prior to organ donation, a plasma BNP or aminoterminal pro-BNP level was obtained. Additional information from the donor included shortening fraction (SF) or ejection fraction, central venous pressure (CVP) reading, and renal function including blood urea nitrogen and creatinine. When available, data from the pulmonary artery (PA) catheter including pulmonary capillary wedge pressure (PCWP) and cardiac index were also collected.

RESULTS

The cohort for the study included eight patients (age range: 6 months to 21 years). The diagnosis of brain death by clinical or radiological examination had been completed in all patients and the patients were scheduled for organ procurement. Myocardial contractility as assessed by echocardiogram using SF was within normal limits. The CVP varied from 7 to 12 mmHg (9 +/- 2) and the PCWP was 10-11 mmHg in the two patients who had PA catheters in place. No patient was receiving inotropic medications. In five of the six patients, the BNP value was above the upper limit of normal (100 pg x ml(-1)). In two patients, an NT-pro-BNP value was obtained and found to be higher than the upper limits of normal (450 pg x ml(-1)). All eight patients were acceptable cardiac donors and the transplanted hearts functioned without difficulty in the recipients.

CONCLUSIONS

Assays of plasma BNP concentrations have been shown to be helpful in differentiating myocardial dysfunction from primary lung disease in both the adult and pediatric population. However, our data demonstrate that mechanisms other than myocardial performance may regulate BNP levels in patients with severe central nervous system injury who progress to brain death. Our preliminary data suggest that these assays appear to be of limited value in assessing myocardial performance in this population.

B-type natriuretic peptide in the emergency diagnosis of critical heart disease in children

OBJECTIVE

The initial presentation of congenital and acquired heart disease in children can present a diagnostic challenge. We sought to evaluate B-type natriuretic peptide as a marker of critical heart disease in children at presentation in the acute care setting.

METHODS

A cohort of 33 pediatric patients with newly diagnosed congenital or acquired heart disease had B-type natriuretic peptide levels obtained on hospital admission after evaluation in an acute care setting. Patients were admitted from March 2005 through February 2007. A noncardiac cohort of 70 pediatric patients who presented with respiratory or infectious complaints had B-type natriuretic peptide levels obtained during emergency department evaluation. A comparison of B-type natriuretic peptide results was performed.

RESULTS

Cardiac diagnoses included cardiomyopathy (14), left-sided obstructive lesions (12), anomalous left coronary artery from the pulmonary artery (4), total anomalous pulmonary venous return (2), and patent ductus arteriosus (1). Cardiac cohort mean age at presentation was 33.6 months. The 33 patients with new cardiac diagnoses had a mean B-type natriuretic peptide level of 3290 pg/mL (SD: +/-1609; range: 521 to >5000 pg/mL). The 70 noncardiac patients' mean age at presentation was 23.1 month, and mean B-type natriuretic peptide level was 17.4 pg/mL (SD: +/-20; range: <5 to 174 pg/mL).

CONCLUSIONS

B-type natriuretic peptide levels were markedly elevated at presentation in the acute care setting for all patients in this cohort of children with newly diagnosed congenital or acquired heart disease. B-type natriuretic peptide levels from noncardiac patients were significantly lower, with no overlap to the cardiac disease group. B-type natriuretic peptide level can be useful as a diagnostic marker to aid in the recognition of pediatric critical heart disease in the acute care setting.

B-type natriuretic peptide levels predict outcomes for children on extracorporeal life support after cardiac surgery

OBJECTIVE

Extracorporeal life support is used in 3% to 8% of infants and children after cardiac surgery. B-type natriuretic peptide may have utility as a biomarker in these patients. The objective of this study was to investigate potential associations between changes in B-type natriuretic peptide during trials off extracorporeal life support and clinical outcome.

METHODS

Ten infants and children requiring extracorporeal life support after cardiac surgery were studied prospectively. Before separation from extracorporeal life support, a shunt was placed in the circuit, allowing for temporary trials off life support. Serum lactate, arterial-venous oxyhemoglobin saturation difference, and B-type natriuretic peptide levels were determined before each trial off life support and at the end of each trial off life support, and the ability to predict postoperative outcome from these data was evaluated.

RESULTS

During trials off extracorporeal life support, lactate, the arterial-venous oxyhemoglobin saturation difference, and B-type natriuretic peptide levels increased above pre-trial values (P < .05). Only the arterial-venous oxyhemoglobin saturation difference predicted successful separation from extracorporeal life support after a trial (P < .05). There were no associations between long-term outcome and alterations in lactate and the arterial-venous oxyhemoglobin saturation difference during the final trials off life support. However, an increase in B-type natruiretic peptide levels during the final trial off life support (trial/pre-trial ratio of >1) had a sensitivity of 80% and a specificity of 100% for predicting the need for an unplanned operation or death within 3 months (P < .05).

CONCLUSION

B-type natriuretic peptide determinations may be a useful tool for clinicians caring for infants and children requiring extracorporeal life support after cardiac surgery.

B-type natriuretic peptide levels predict outcome after neonatal cardiac surgery

OBJECTIVES

Neonates undergoing cardiac surgery are at high risk for adverse outcomes. B-type natriuretic peptide is used as a biomarker in patients with cardiac disease, but the predictive value of B-type natriuretic peptide after cardiac surgery in neonates has not been evaluated. Therefore, the objective of this study was to determine the predictive value of perioperative B-type natriuretic peptide levels for postoperative outcomes in neonates undergoing cardiac surgery.

METHODS

Plasma B-type natriuretic peptide determinations were made before and 2, 12, and 24 hours after surgery in 36 consecutive neonates. B-type natriuretic peptide levels and changes in perioperative B-type natriuretic peptide were evaluated as predictors of postoperative outcome.

RESULTS

B-type natriuretic peptide levels at 24 hours were lower than preoperative levels (24-h/pre B-type natriuretic peptide ratio < 1) in 29 patients (81%) and higher (24-h/pre B-type natriuretic peptide ratio > or = 1) in 7 patients (19%). A 24-hour/pre B-type natriuretic peptide level of 1 or greater was associated with an increased incidence of low cardiac output syndrome (100% vs 34%, P = .002) and fewer ventilator-free days (17 +/- 13 days vs 26 +/- 3 days, P = .002), and predicted the 6-month composite end point of death, an unplanned cardiac operation, or cardiac transplant (57% vs 3%, P = .003). A 24-hour/pre B-type natriuretic peptide level of 1 or greater had a sensitivity of 80% and a specificity of 90% for predicting a poor postoperative outcome (P = .003).

CONCLUSION

In neonates undergoing cardiac surgery, an increase in B-type natriuretic peptide 24 hours after surgery predicts poor postoperative outcome.

Advances in cardiac intensive care

PURPOSE OF REVIEW

As surgical survival in children with congenital heart disease, particularly those with univentricular hearts, has improved in recent years, focus has shifted to reducing the morbidity of congenital cardiac malformations and their treatment. This review will focus on emerging therapies aimed at reducing these morbidities in the intensive care unit.

RECENT FINDINGS

A protracted stay in the intensive care unit after cardiac surgery is a risk factor for developing various morbidities. Therapies or interventions that may hasten postoperative recovery and minimize the length of stay are thus important to evaluate. Fluid overload, renal dysfunction, low cardiac output and neurological dysfunction remain major contributors to morbidity after cardiac surgery. In addition, the treatment of these adverse states can potentially compound the injury.

SUMMARY

The reduction in morbidity after cardiac surgery remains challenging. Recent insights have allowed us to recognize the impact of factors beyond the intraoperative period as significant contributors to morbidity. As our field continues to evolve, future studies should focus on emerging technologies and therapies that facilitate the prevention of physiological states that compound congenital morbidities.