Sedation and Analgesia Following Pediatric Heart Surgery—Less May Be More*
For pediatric patients in the immediate postoperative period after cardiothoracic surgery (CTS), there is an additional component of postoperative analgesia and sedation. In certain cases, it is clinically important to avoid increased cardiac output demands imposed by pain and agitation (2). Postoperative pulmonary hypertension and low cardiac output syndrome occur frequently after congenital heart surgery (3–5) and may be managed effectively in an intubated and sedated patient. Studies have shown that modulating the stress response to pediatric CTS by different intraoperative fentanyl dosing strategies may result in a less complicated postoperative course (6). Older work showed, in contrast, that different fentanyl anesthesia techniques did not alter the stress response to surgery (7)and do not have an impact on postoperative course.
Some centers have instituted successful fast track CTS programs (8, 9) in which an anesthetic is conducted so that extubation can occur in the operating room or shortly after arrival in the ICU. Early extubation has significant advantages for pediatric patients after CTS (2), but numerous challenges remain. Extubated CTS patients have acute pain from midline sternotomies, chest drains, arterial and central venous catheters, and transthoracic pacing wires, and are at risk of bleeding from cardiac suture lines, cardiopulmonary bypass cannulation sites, and their chest incision. Being extubated places limits on the amounts of potent analgesics and sedatives that can be administered without inducing respiratory depression.
There is yet much to learn about sedation and analgesia in pediatric patients. The work of Curley et al (10) provided a large repository of data examining usual sedation and analgesia practices among pediatric intensive care practitioners as well as demonstrated that a nurse-directed sedation protocol that uses the State Behavioral Score (11) can be used successfully. Pharmacologic analgesics and sedatives can create a host of problems such as respiratory depression, hypotension that may require fluid loading and vasopressor use, gastrointestinal tract dysfunction, and delirium. Although well known in critically ill adults, the existence, impact, and factors contributing to delirium have only recently become known in critically ill infants and children (12, 13). The frequent use of benzodiazepines as adjuncts to opioids in PICU patients makes the recently discovered association of benzodiazepine use with delirium of special relevance (14, 15). ICU practitioners must remain aware of evolving research on long-term neurodevelopmental effects of anesthesia in children (16) and keep this awareness in context with the extensive literature of developmental impacts of congenital heart disease and its repair. Despite new agents in the pharmacopeia of analgesia and sedation, the management of abstinence with long courses of enteral agents continues to occur.
In this issue of Critical Care Medicine, Penk et al (17) demonstrate interesting and thought-provoking points about postoperative analgesia and sedation in pediatric patients recovering from CTS.