Risk assessment and anesthesia management in children with congenital heart disease undergoing non-cardiac surgery

The prevalence of congenital heart disease is about 8 to 10 case per 1000 live births and is a major cause of increased mortality and morbidity in pediatric patients undergoing noncardiac surgery. Therefore safe anesthesia and adequate recovery should be provided. It is important to determine the patient’s risk score in the preoperative period. However, the risk assessment tools have a limited prediction for increased mortality and morbidity of non-cardiac surgery. The most important point in determining the anesthesia method is to be aware of the latest situation both anatomically and physically about the circulation of patient and to create the specifi c planning. In these patients, the aim of maintenance of anesthesia is to increase arterial oxygen saturation by increasing pulmonary blood fl ow. Thus the use of appropriate anesthesia and monitoring methods through multidisciplinary decision-making and planning, as well as the identifi cation of high-risk patients based on risk classifi cation, may reduce mortality and morbidity in the pediatric patients with congenital heart disease. Review Article Risk assessment and anesthesia management in children with congenital heart disease undergoing non-cardiac surgery Kemal Tolga Saracoglu1*, Ayten Saracoglu2 and Recep Demirhan3 1Department of Anesthesiology and Intensive Care, Health Sciences University School of Medicine, Istanbul, Turkey 2Department of Anesthesiology and Intensive Care, Marmara University School of Medicine, Istanbul, Turkey 3Department of Thoracic Surgery, Health Sciences University School of Medicine, Istanbul, Turkey Received: 02 March, 2019 Accepted: 07 May, 2019 Published: 08 May, 2019 *Corresponding author: Dr. K Tolga Saracoglu, Kartal Dr. Lutfi Kirdar Training and Research Hospital Semsi denizer Cd. E-5 Karayolu Cevizli Mevkii 34890 Kartal Istanbul Turkey, Tel: +90 216 4413900; Fax: +90 216 3520083; E-mail:


Introduction
Congenital heart disease is a cause of increased mortality and morbidity in pediatric patients undergoing noncardiac surgery. In United States the prevalence of congenital heart disease is about 8 to 10 case per 1000 live births [1].
Hemodynamic instability in the perioperative period, increased need for postoperative mechanical ventilation and prolonged hospital stay are the most common complications in these patients. Proper preparation is necessary before surgery in order to reduce the incidence of such complications. The main objectives are to perform procedures in a fully-equipped medical center, with proper consultations and appropriate monitoring. Safe anesthesia and adequate recovery should be provided by an experienced anesthesia team. Today, 90% of children with congenital heart disease are able to reach the adult period thanks to prenatal diagnosis and interventions, improvements in surgical techniques, and improved intensive care support [2]. 30% of these patients undergo noncardiac surgery at least once until 5 years of age due to concomitant trachea-esophageal fi stula, anorectal anomalies, cleft palate, lip or non-cardiac anomalies originating from the renal system.
Several interventions in these patients may lead to undesirable hemodynamic responses.
In the National Surgical Quality Improvement Project  [3]. In a study conducted in a group of patients undergoing non-cardiac surgery, 22% of patients with congenital heart disease developed cardiac arrest, and half of them occurred during non-cardiac procedures [4]. The mean age of these patients was below 2 years of age and half of the patients were younger than 6 months. 24% of patients with cardiac arrest were identifi ed as single ventricle, 26% as outfl ow obstruction and 18% had left to right shunt. The presence of ventricular dysfunction with the use of preoperative angiotensin converting enzyme (ACE) inhibitor, inotropic agents and digoxin were found to be associated with prolonged hospital stay in the postoperative period. On the other hand, several airway abnormalities may complicate the course of congenital heart disease [5]. Besides, during resuscitation, pediatric tracheal intubation requires experience and training, thus presents a high incidence of complications [6]. Systemic vascular resistance changes caused by general anesthetic agents reduce pulmonary blood fl ow in the presence of shunt. The idea that the blood pressure described by the Ohm's law is proportional to the heart rate and stroke volume may not be valid in these patients. Because it will not increase the discharge volume of the ventricle with a limited capacity of fl uid loading to increase the stroke volume.

Risk assessment
The American Society of Anesthesiologist's Physical Status Score (ASA-PS) and NARCO-SS (neurological, airway, respiratory, cardiovascular, surgical score) are used in the pediatric patient group to determine the patient's risk score in the preoperative period [7]. However, as in pediatric patients with congenital heart disease, they have a limited prediction for increased mortality and morbidity of non-cardiac surgery. Pediatric Perioperative Cardiac Arrest (POCA) study found that perioperative cardiac arrest was present in 34% of patients with congenital heart disease undergoing noncardiac surgery in a 11-year period. The most important factors that determine the risk for the surgical procedure of these patients were determined as the patient's age, severity of cardiac anomaly and accompanying comorbidities. In another retrospective analysis, 47% of the patients were found to have a prolonged intensive care stay after elective noncardiac surgery [8]. However, the variety of heart disease and surgical procedures leads to diffi culties in determining the patient's risk. In different studies, the complexity of heart disease, type of cardiac surgery and the functional capacity of the patient have been shown to be effective on postoperative complications. In order to determine the appropriate anesthesia approach for both pathophysiological and anatomical differences, risk assessment should be performed to reduce the complications and to ensure the effi cient use of resources [9]. For this purpose, the pediatric patients with congenital heart disease were evaluated in the Risk Adjustment for Congenital Heart Surgery Score (RACHS-1), Aristotle Basic Complexity Score (ABC score) and Society of Thoracic Surgeons and the European Association for Cardiothoracic Surgery Mortality (STS-EACTS) scoring systems are used and are more specifi c to cardiac surgery. Several patients have associated diseases such as esophageal atresia. Waterson risk classifi cation is used for the perioperative risk assessment [10].
Faraoni et al. [11], developed a risk model based on patient data from the records of the American College of Surgeons National Surgical Quality Improvement Program which included 4375 pediatric patients between 2012-2014. In addition to inotropic agent support, mechanical ventilation, cardiopulmonary resuscitation and chronic kidney damage, which are considered as preoperative critical disease markers; the severity of heart disease and the type of lesion were determined as an independent predictor of in-hospital mortality following non-cardiac surgery. In another study, patients were studied in three groups: high, medium and low risk [9].

Conclusions
The use of appropriate anesthesia and monitoring methods through multidisciplinary decision-making and planning, as well as the identifi cation of high-risk patients based on risk classifi cation, may reduce mortality and morbidity in the pediatric patients with congenital heart disease.