Nefopam for refractory postoperative hiccups

Refractory postoperative hiccups is an uncommon but distressing condition that may cause deleterious effects such as wound dehiscence, infection, fatigue, and dehydration. Hiccups–brief bursts of intense inspiratory activity involving the diaphragm and inspiratory intercostal muscles, with reciprocal inhibition of the expiratory intercostal muscles–might result from structural or functional disturbances of the medulla or of afferent or efferent nerves to the respiratory muscles (1). The first line of management is to reverse or treat any underlying cause such as esophageal obstruction or gastric distention. In most cases, hiccups respond to stimulation of the pharynx or the external auditory meatus, or to vagal maneuvers. Increasing the partial pressure of inspired carbon dioxide (rebreathing) reduces the frequency of hiccups, and reducing carbon dioxide pressure (hyperventilation) increases the amplitude of hiccups (2). Patients with persistent hiccups have been treated with several classes of drugs: chlorpromazine, carbamazepine, nifedipine, nimodipine, baclofen, metoclopramide, haloperidol, ketamine, phenytoin and lidocaine (2–4). All have potentially serious adverse effects and some may be contraindicated in the postoperative setting. Invasive techniques proposed for the control of refractory hiccups include glossopharyngeal nerve block (5) and phrenic nerve block (6). Both procedures reduce vital capacity, may cause dyspnea or hypoxia, and may fail to stop hiccups (7). We previously reported (8) that severe hiccups in medical patients responds to treatment with nefopam– 3,4,5,6-Tetrahydro-5-methyl-l-phenyl-1H-2.5-benoxazo-cine hydrochloride (Oxadol, Kedrion, Italy)–a nonopioid analgesic drug with shivering suppression properties (9). In this study we describe the use of nefopam in seven patients with postoperative hiccups refractory to standard therapeutic maneuvers: gastric decompression, vagal maneuvers (Valsalva maneuver, carotid and optic compression), pharynx and external auditory meatus stimulation, and carbon dioxide rebreathing. This series includes all cases of refractory postoperative hiccups we observed over the past 2 yr as anesthesiologists in a university hospital.