Preproopiomelanocortin and preprodynorphin mRNA expressions in rat brain after electroacupuncture + droperidol. (1/100)

AIM: To study the expression of preproopiomelanocortin (POMC) and preprodynorphin (PPD) mRNA following the combination of electroacupuncture (EA) with droperidol (Dro), a dopamine receptor antagonist. METHODS: The brains and spinal cords of Sprague-Dawley rats were sectioned after combination of EA with Dro, and the gene expression was investigated using nonradioactive in situ hybridization histochemistry (ISHH). RESULTS: Ten hours after EA, the POMC mRNA expression was enhanced; the expression was further enhanced when EA was combined with Dro. The expression of PPD mRNA showed regional difference in central nervous system (CNS): in spinal cord, EA enhanced the PPD mRNA expression and the combination of EA with Dro further promoted the expression; in the brain, the PPD mRNA expression after EA or combination of EA with Dro showed no obvious change in most regions (caudate-putamen, accumbens, arcuate nucleus of hypothalamus) or was decreased in supraoptic nucleus. CONCLUSION: Dro combined with EA promoted the expression of POMC mRNA in CNS and PPD mRNA in spinal cord, but reduced or had no effect on PPD mRNA expression in the brain.  (+info)

Ondansetron and droperidol in the prevention of postoperative nausea and vomiting. (2/100)

We have performed a prospective, randomized, double-blind clinical study to assess the efficacy of ondansetron, droperidol, or both, in preventing postoperative emesis. We studied 242 patients undergoing biliary or gynaecological surgery under general anaesthesia. Shortly before induction of anaesthesia, patients received: saline i.v. (group I, n = 62); droperidol 2.5 mg i.v. (group 2, n = 60); ondansetron 4 mg i.v. (group 3, n = 57); or droperidol 2.5 mg with ondansetron 4 mg i.v. (group 4, n = 63). Nausea occurred in 45%, 37%, 32% and 29% (P = 0.234) and vomiting in 23%, 17%, 9% and 5% (P = 0.016) of patients in groups 1, 2, 3 and 4, respectively, during the first 24 h. Groups 2 and 4 had greater sedation scores than group 1 during the first 3 h (P < 0.01). We conclude that both droperidol and ondansetron showed a significant antiemetic effect, ondansetron was not significantly better than droperidol, and the combination of droperidol and ondansetron was better than droperidol but no better than ondansetron alone.  (+info)

Cost-effectiveness of prophylactic antiemetic therapy with ondansetron, droperidol, or placebo. (3/100)

BACKGROUND: In an era of growing economic constraints on healthcare delivery, anesthesiologists are increasingly expected to understand cost analysis and evaluate clinical practices. Postoperative nausea and vomiting (PONV) are distressing for patients and may increase costs in an ambulatory surgical unit. The authors compared the cost-effectiveness of four prophylactic intravenous regimens for PONV: 4 mg ondansetron, 0.625 mg droperidol, 1.25 mg droperidol, and placebo. METHODS: Adult surgical outpatients at high risk for PONV were studied. Study drugs were administered intravenously within 20 min of induction of nitrous oxide-isoflurane or enflurane anesthesia. A decision-tree analysis was used to group patients into 12 mutually exclusive subgroups based on treatment and outcome. Costs were calculated for the prevention and treatment of PONV. Cost-effectiveness analysis was performed for each group. RESULTS: Two thousand sixty-one patients were enrolled. Efficacy data for study drugs have been previously reported, and the database from that study was used for pharmacoeconomic analysis. The mean-median total cost per patient who received prophylactic treatment with 4 mg ondansetron, 0.625 mg droperidol, 1.25 mg droperidol, and placebo were $112 or $16.44, $109 or $0.63, $104 or $0.51, and $164 or $51.20, respectively (P = 0.001, active treatment groups vs. placebo). The use of a prophylactic antiemetic agent significantly increased patient satisfaction (P < 0.05). Personnel costs in managing PONV and unexpected hospital admission constitute major cost components in our analysis. Exclusion of nursing labor costs from the calculation did not alter the overall conclusions regarding the relative costs of antiemetic therapy. CONCLUSION: The use of prophylactic antiemetic therapy in high-risk ambulatory surgical patients was more effective in preventing PONV and achieved greater patient satisfaction at a lower cost compared with placebo. The use of 1.25 mg droperidol intravenously was associated with greater effectiveness, lower costs, and similar patient satisfaction compared with 0.625 mg droperidol intravenously and 4 mg ondansetron intravenously.  (+info)

Differential block of fast and slow inactivating tetrodotoxin-sensitive sodium channels by droperidol in spinal dorsal horn neurons. (4/100)

BACKGROUND: Dorsal horn neurons of the spinal cord participate in neuronal pain transmission. During spinal and epidural anesthesia, dorsal horn neurons are exposed to local anesthetics and opioids. Droperidol is usually given with opioids to avoid nausea and vomiting. A recently developed method of "entire soma isolation" has made it possible to study directly the action of droperidol on different components of Na+ current in dorsal horn neurons. METHODS: Using a combination of the whole-cell patch-clamp recording from spinal cord slices and the entire soma isolation method, we studied the direct action of droperidol on two types of Na+ currents in dorsal horn neurons of young rats. RESULTS: The tetrodotoxin-sensitive Na+ current in isolated somata consisted of a fast inactivating (tauF, 0.5-2 ms; 80-90% of the total amplitude) and a slow inactivating (tauS, 6-20 ms; 10-20% of the total amplitude) component. Droperidol, at concentrations relevant for spinal and epidural anesthesia, selectively and reversibly suppressed the fast component with a half-maximum inhibiting concentration (IC50) of 8.3 microm. The slow inactivating component was much less sensitive to droperidol; the estimated IC50 value was 809 microm. CONCLUSIONS: Droperidol selectively blocks fast Na+ channels, the fast and slow components of the Na+ current in dorsal horn neurons are carried through pharmacologically distinct types of Na+ channels, and the effects of droperidol differ from those of local anesthetics and tetrodotoxin, which equipotently suppress both components. Droperidol may be suggested as a pharmacologic tool for separation of different types of inactivating tetrodotoxin-sensitive Na+ channel.  (+info)

A comparison of antiemetic efficacy of droperidol alone and in combination with metoclopramide in day surgery anaesthesia. (5/100)

We have studied the antiemetic efficacy of droperidol alone, and in combination with metoclopramide in first trimester termination of pregnancy in day surgery. The aim was to determine whether the addition of metoclopramide could further reduce the incidence of postoperative nausea and vomiting (PONV) but avoid excessive sedation. Group I (control, n = 40) received i.v. droperidol 0.625 mg at induction. Group II (study, n = 40) received i.v. droperidol 0.625 mg and i.v. metoclopramide 10 mg at induction. The incidence of nausea at 1 and 2 hours postoperatively was 23% and 10% in group I, and 5% and nil in group II respectively. The difference in the incidence of nausea was significant at p < 0.05 at one hour but not at two hours postoperatively. No patients vomited. There was no difference in the sedation and pain score between them. We did not observe any significant side effects attributable to either drug. All patients were discharged home within 3 hours. We conclude that in the prevention of PONV, the combination of metoclopramide and droperidol is superior to the use of droperidol alone at one hour but not at two hours postoperatively.  (+info)

Effects of fentanyl and droperidol on canine left ventricular performance. (6/100)

The effects of fentanyl and droperidol on left ventricular performance were evaluated in the neurally intact dog right-heart-bypass preparation under conditions of constant cardiac output, arterial pressure, and heart rate. Fentanyl, .01 and .02 mg/kg body weight, and droperidol, 0.5 mg/kg, did not affect left ventricular performance. However 1.0 mg/kg droperidol caused a significant (P less than .05) increase in left ventricular end-diastolic pressure and a small decrease in maximum left ventricular dP/dt (.05 less than P less than .10). No significant change in myocardial oxygen consumption was observed. This study indicates that large doses of droperidol may depress left ventricular performance and may account for a portion of the hypotension observed after its administration in man. (Key words: Anesthetics, intravenous, fentanyl; Anesthetics; intravenous, droperidol; Heart, function, fentanyl; Heart, function, droperidol.).  (+info)

Hemodynamic and ventilatory responses to fentanyl, fentanyl-droperidol, and nitrous oxide in patients with acquired valvular heart disease. (7/100)

Fentanyl (10 mug/kh) or fentanyl (10 mug/kg) plus droperidol (100 mug/kg) administered intravenously during 20 minutes to adult patients with acquired valvular heart disease produced minimal circulatory changes. The trend during drug infusion was for mean arterial pressure and systemic vascular resistance to decrease, and for cardiac index and stroke volume index to increase without change in heart rate. Central venous pressure increased during drug infusion (P less than 0.05) but decreased to awake levels following controlled ventilation and skeletal-muscle paralysis, probably reflecting thoracoabdominal-muscle rigidity rather than a circulatory response. Hypoventilation during drug infusion necessitated assisted or controlled ventilation, with or without skeletal muscle paralysis, in 14 of 16 patients. Addition of 60 per cent nitrous oxide following fentanyl or fentanyl-droperidol infusion significantly decreased mean arterial pressure, heart rate, and cardiac index. All circulatory changes were similar in direction and extent to those previously found during morphine-nitrous oxide anesthesia. (Key words: Anesthetics, intravenous, fentanyl; Anesthetics, gases, nitrous oxide; Heart, effect of fentanyl, dorperidol, and nitrous oxide.).  (+info)

Suppression of potassium conductance by droperidol has influence on excitability of spinal sensory neurons. (8/100)

BACKGROUND: During spinal and epidural anesthesia with opioids, droperidol is added to prevent nausea and vomiting. The mechanisms of its action on spinal sensory neurons are not well understood. It was previously shown that droperidol selectively blocks a fast component of the Na+ current. The authors studied the action of droperidol on voltage-gated K+ channels and its effect on membrane excitability in spinal dorsal horn neurons of the rat. METHODS: Using a combination of the patch-clamp technique and the "entire soma isolation" method, the action of droperidol on fast-inactivating A-type and delayed-rectifier K+ channels was investigated. Current-clamp recordings from intact sensory neurons in spinal cord slices were performed to study the functional meaning of K+ channel block for neuronal excitability. RESULTS: Droperidol blocked delayed-rectifier K+ currents in isolated somata of dorsal horn neurons with a half-maximum inhibiting concentration of 20.6 microm. The A-type K+ current was insensitive to up to 100 microm droperidol. At droperidol concentrations insufficient for suppression of an action potential, the block of delayed-rectifier K+ channels led to an increase in action potential duration and, as a consequence, to lowering of the discharge frequency in the neuron. CONCLUSIONS: Droperidol blocks delayed-rectifier K+ channels in a concentration range close to that for suppression of Na+ channels. The block of delayed-rectifier K+ channels by droperidol enhances the suppression of activity in spinal sensory neurons at drug concentrations insufficient for complete conduction block.  (+info)