A number of factors need to be considered in determining whether a patient is a candidate for PCA therapy. The most important factor is that the patient must be able to understand the relationships between pain, pushing the PCA button, and pain relief (Pasero, Quinn, Portenoy, McCaffery, & Rizos, 2011). When PCA is warranted, patients should be carefully screened for their cognitive and physical ability to manage their pain by that method. Clinicians often hesitate to prescribe PCA for children, believing that they are too young to understand the concept of PCA and how to use the pump appropriately. However, PCA has been used effectively and safely in developmentally normal children as young as 4 years old (Wellington & Chia, 2009). Intravenous PCA has been shown for many years to be safe in older patients (Gagliese, Gauthier, Macpherson, Jovellanos, & Chan, 2008), but providers often do not prescribe it for fear of producing confusion in these patients. Although the opioid (by whatever approach it is delivered) can contribute to confusion, the factors that may be responsible for postoperative confusion are numerous (Bagri, Rico, & Ruiz, 2008; Redelmeier, 2007; Sharma et al., 2005; Zakriya et al., 2002), and its development should not be assumed to be related to either the drug or the delivery approach. For example, the presence of postoperative pain and increased intensity of postoperative pain have been found to be independent predictors of postoperative delirium (Vaurio, Sands, Wang, Mullen, & Leung, 2006).