Learning Objective #1: Describe the mechanisms of nausea and vomiting occurring after different surgeries | |||
Learning Objective #2: Discuss current best evidence of various intervention strategies to reduce postoperative nausea and vomiting |
The choices of anti-emetic drugs depend not only on the patient status and the severity of PONV, but also on the potential adverse side effects and available routes of administrations for therapies. Five major categories of drugs include serotonin antagonist (longer lasting with fewer adverse effects), dopamine antagonist (for mild and moderate PONV), antihistamine (blocking histamine type-1 receptors for vestibular apparatus, good for ear surgeries), Phenergan (for motion sickness affecting vestibular apparatus when patients are transferred between units), and dopamine (higher dose for anxiety and agitation). A recent meta-analysis of 17 trials on combination therapy with multiple drugs indicated the need for more severe patients.
Non-pharmacological interventions for PONV include dietary and behavioral interventions. Clear liquid diet before the surgery and diet of easy-for-digestion are better choices with relaxing meal times. Relaxation and music therapies reduced PONV. The most effective alternative treatments include acupressure and acupuncture therapy on Pericardium 6 meridian point. There is a growing body of literature on other complementary therapies including ginger, peppermint, supplemental oxygen, isopropyl alcohol inhalation, intravenous fluid administration, slow movement, repositioning, deep breathing, cool washcloths, and mouth care. Complementary therapies are inexpensive and some are every effective, thus carry great promises for future research and practice. A clinical care guideline in a modern surgical unit will be presented including preoperative and postoperative assessment for PONV based on the best evidence to improve care outcomes.