Local Anesthesia Thoracoscopy with versus without Midazolam: A Randomized Controlled Trial.

BACKGROUND: Medical thoracoscopy is the gold standard for the diagnosis of pleural diseases. To date, no consensus exists regarding the choice of sedative and analgesic agents in patients undergoing local anesthetic thoracoscopy (LAT), and questions are raised as to whether sedatives may add to respiratory side effects. OBJECTIVE: The aim of the study was to test the hypothesis that administration of midazolam associated with lidocaine versus lidocaine alone in patients with LAT adds to respiratory side effects. METHODS: We randomly assigned 80 patients to a 1:1 study to 2 groups: local anesthesia by lidocaine (n = 40) versus lidocaine and midazolam (n = 40), with the primary end point being the mean lowest oxygen saturation. The secondary end points were cardiovascular parameters, complications, days of drainage, hospital stay, and patients' quality of life (QoL) as assessed by a visual analog scale (VAS). RESULTS: The mean age of all patients was 66.6 ± 13.1 years. The study comprised 50 males (62.5%). No difference was observed in the demographics between the 2 groups. No significant difference was observed between the 2 groups in oxygen saturation (primary end point). A significant difference was observed in favor of the midazolam group regarding the QoL assessed by VAS. CONCLUSION: Midazolam does not add to respiratory side effects when it is used with lidocaine for LAT, while patients' QoL is actually improved in this group. Therefore, in our department, we changed our startegy in favor of the association of lidocaine and midazolam.

Pharmaceutical agents known to produce disulfiram-like reaction: effects on hepatic ethanol metabolism and brain monoamines.

Several pharmaceutical agents produce ethanol intolerance, which is often depicted as disulfiram-like reaction. As in the case with disulfiram, the underlying mechanism is believed to be the accumulation of acetaldehyde in the blood, due to inhibition of the hepatic aldehyde dehydrogenases. In the present study, chloramphenicol, furazolidone, metronidazole, and quinacrine, which are reported to produce a disulfiram-like reaction, as well as disulfiram, were administered to Wistar rats and the hepatic activities of alcohol and aldehyde dehydrogenases (1A1 and 2) were determined. The expression of aldehyde dehydrogenase 2 was further assessed by Western blot analysis, while the levels of brain monoamines were also analyzed. Finally, blood acetaldehyde was evaluated after ethanol administration in rats pretreated with disulfiram, chloramphenicol, or quinacrine. The activity of aldehyde dehydrogenase 2 was inhibited by disulfiram, chloramphenicol, and furazolidone, but not by metronidazole or quinacrine. In addition, although well known for metronidazole, quinacrine also did not increase blood acetaldehyde after ethanol administration. The protein expression of aldehyde dehydrogenase 2 was not affected at all. Interestingly, all substances used, except disulfiram, increased the levels of brain serotonin. According to our findings, metronidazole and quinacrine do not produce a typical disulfiram-like reaction, because they do not inhibit hepatic aldehyde dehydrogenase nor increase blood acetaldehyde. Moreover, all tested agents share the common property to enhance brain serotonin, whereas a respective effect of ethanol is well established. Therefore, the ethanol intolerance produced by these agents, either aldehyde dehydrogenase is inhibited or not, could be the result of a "toxic serotonin syndrome," as in the case of the concomitant use of serotonin-active medications.