Anesthetic Considerations for Patients with Congenital Heart Disease

Congenital heart disease (CHD) is one of the most common inborn defects, occurring in approximately 8 in 1,000 live births. Before the development of pediatric cardiac surgery, fewer than 20% of children with CHD survived to adulthood. Now, more than 85% of children with CHD can expect to live into adulthood. In fact, estimates suggest that, for the first time in history, more adults than children are living with CHD in the United States (1). Many of these patients will require additional palliative or curative cardiac surgery and noncardiac surgery at some time during adulthood. As patients with CHD demonstrate specific and complex anatomy and physiology, they are at risk for perioperative morbidity and mortality, and thus present unique challenges for the anesthesiologist.

A good preoperative assessment is essential to determine the physiological status of the patient. A multidisciplinary approach that includes the participation of anesthesiologists, cardiologists, intensivists, and surgeons is best. It must be noted that perioperative risk is substantially increased in adults with CHD, and major surgery and procedures that involve one lung ventilation or changes in position could produce important hemodynamic effects that contribute to increasing risk (2). Therefore, the anesthesiologist should be familiar with the patient’s specific anatomy and physiology, as determined from echocardiographic and cardiac catheterization results. This knowledge is useful to anticipate intraoperative events that may precipitate acute changes in the magnitude or direction of intracardiac shunts or modulate flow through systemic to pulmonary shunts (2).

CHD is an important risk factor for the development of infective endocarditis (bacterial infection of the endocardium). Both the American Heart Association and the European Society of Cardiology recommend that, for patients at high and moderate risk, antibiotic prophylaxis should be used when performing procedures associated with a risk of bacteraemia (1). This is limited patients with previous endocarditis, unrepaired cyanotic CHD, including palliative shunts and conduits; completely repaired congenital heart defects with prosthetic material or device, whether placed by surgery or by catheter intervention, during the first 6 months after the procedure; repaired CHD with residual defects at the site or adjacent to the site of a prosthetic patch or prosthetic device (which inhibit endothelialization). Except for the conditions listed above, antibiotic prophylaxis is no longer recommended for other forms of CHD (2).

Unfortunately, there are no evidence-based recommendations to guide the anesthetic management of patients with CHD undergoing noncardiac surgery. Given the large scope of abnormalities encompassed by CHD, it is also impossible to propose a single approach for anesthetic management that would address every possible defect. However, the most important aspect of the perioperative care is the involvement of a team with a detailed understanding of the patient’s cardiac defect, their functional status and anticipation of the perioperative stresses (1). Sevoflurane is an agent of choice for inhalation induction. Propofol or ketamine are used for IV induction (3).The circulatory effects of the IV induction agents are well known. All of the commonly used IV induction agents can be used safely – the rate and dose administered are more important than the actual drug used. All are associated with a reduction in systemic vascular resistance (SVR) to some degree, and if a right‐to‐left shunt is present, this will increase. The effect of right‐to‐left shunting on delaying the uptake of inhalational agents is rarely problematic, although inhalational induction of anesthesia is prolonged. In patients with simple cardiac lesions, halothane, isoflurane and sevoflurane do not change the degree of left‐to‐right shunt in patients ventilated with 100% oxygen. However, this cannot be extrapolated to patients with complex CHD, or those with right‐to‐left shunts (1).

Post-operative care should be given by experienced staff caring for this subset of patients, and complications, such as dysrhythmias, bleeding and thromboembolic events should be addressed (3). The number of adult patients with CHD is rapidly increasing, and these patients will be presenting with greater frequency for noncardiac surgery. The cardiovascular anatomy and physiology of CHD are complex and require specific knowledge of the defect and its anesthetic implications. Large-scale clinical trials are required to elucidate the optimal anesthetic management of these challenging patients (2).

References

1. A. T. Lovell, Anaesthetic implications of grown‐up congenital heart disease, BJA: British Journal of Anaesthesia, Volume 93, Issue 1, July 2004, Pages 129–139, https://doi.org/10.1093/bja/aeh172
2. Maxime Cannesson, Michael G. Earing, Vincent Collange, Judy R. Kersten; Anesthesia for Noncardiac Surgery in Adults with Congenital Heart Disease. Anesthesiology 2009;111(2):432-440. doi: https://doi.org/10.1097/ALN.0b013e3181ae51a6.
3. Junghare, S. W., & Desurkar, V. (2017). Congenital heart diseases and anaesthesia. Indian journal of anaesthesia, 61(9), 744–752. https://doi.org/10.4103/ija.IJA_415_17