Tong J. Gan
Print Publication Year: 2009
Online Publication Date:October 2009
Chapter DOI: http://dx.doi.org/10.1017/CBO9780511576706.027
Acute pain is common and occurs most often in the immediate postoperative period. Acute nonsurgical pain related to burns injury, trauma, sickle cell crisis, ureteric colic, and acute pancreatitis are also commonly encountered in the hospital. The role of opioids in acute pain management is well established. The high efficacy profile and selectivity of potent opioids provides effective management of severe postsurgical pain, particularly in settings where nonopioid pain relievers are inadequate (refer to Chapter 15, Clinical Application of Epidural Analgesia). In general, opioids share a collection of annoying to serious adverse effects and potentially life-threatening complications (Table 25.1). In general, the higher the dose of opioid administered, the greater the incidence and severity of adverse effects. However, there are interindividual variations and some patients may be exquisitely sensitive to the class in general, whereas others developmore side effects with one particular opioid compared to another. Opioid pharmacotherapy therefore requires careful drug selection and dose titration to achieve a satisfactory balance between analgesia and adverse effects.
With greater understanding of their pharmacokinetics and pharmacodynamics, opioids have been administered via different routes to achieve greater efficacy in treating pain (Table 25.2). Consequently, there is also a difference in the type and incidence of adverse effects associated with the various routes of administration.
CARDIOVASCULAR ADVERSE EFFECTS
In general, opioids, particularly rapid-acting lipophilic agents, exhibit vagomimetic effects that tend to slow heart rate.