Eighty ASA I-III patients were randomly assigned to four groups. Group I patients received rocuronium 0.6 mg kg-1 immediately prior to thiopentone, while patients in group II received the same dose immediately after the induction agent. In groups III and IV a priming dose of rocuronium 0.04 mg kg-1 was administered prior to induction. Group III patients received rocuronium immediately prior to thiopentone. In group IV, suxamethonium 1.5 mg kg-1 was administered immediately after thiopentone. Intubation conditions were scored by a blinded investigator. An intubation time of > 60 s was defined as a failure. All patients could be intubated within 60 s. Priming with rocuronium did not improve intubation conditions. Total intubation scores > 6 occurred significantly more often in group II (P < 0.01 vs. all other groups). A single bolus dose of rocuronium 0.6 mg kg-1 (2 x ED95) administered immediately prior to thiopentone 6 mg kg-1 offers the same intubation conditions as suxamethonium 1.5 mg kg-1.
Histamine is a well known causal factor in a variety of clinical events and complications, especially in allergic and anaphylactoid reactions. We therefore investigated whether a dose-dependent therapeutic effect of H-1 + H-2-antagonists (dimethindene maleate + cimetidine) could be shown in the treatment of a histamine-induced cardiovascular reactions in humans. 6 healthy male volunteers participated in a randomized single-blind crossover-study. A histamine dosage leading to a decrease of the mean arterial pressure to 60 mmHg within 2 min was continuously infused over a period of 15 min on two occasions. The volunteers received either histamine + saline or histamine + treatment first. Treatment started 3 min after the start of the histamine infusion (4 mg dimethindene maleate + 200 mg cimetidine i.v.) and was repeated every 2 min until the cardiovascular baseline values were reached or 15 min were completed. Statistical analysis of the treatment effect was performed on an intraindividual basis (ANOVA) with p < 0.05 In both treatment courses mean MAP decreased to about 60 mmHg. While in the saline group MAP remained at this low level during the time of histamine infusion, all volunteers quickly responded to treatment with dimethindene maleate + cimetidine. After 8 mg dimethindene maleate + 400 mg cimetidine MAP reached baseline values in all volunteers (p < 0.01). Mean HR increased to 119 bpm in the saline group after 3 min. Treatment with dimethindene maleate + cimetidine showed similar efficacy against histamine-induced tachycardia (p < 0.01). It may thus be concluded that usual dosages of H-1- and H-2-receptor-antagonists are effective in the treatment of histamine-induced cardiovascular reactions.
Stress ulcer bleeding occurs in special risk groups. The main cause of this complication is the loss of protective mechanisms of the gastric mucosa. Preventive measures aim to strengthen the protective mechanisms or to lower the aggressive factors, mainly the gastric acid. Meta-analysis demonstrates that drugs that enhance the protective mechanisms are superior to a regimen that only reduces the secretion of gastric acid. The most important side effects of stress ulcer prophylaxis are related to the inhibition of gastric acid, the blockade of the cytochrome P450 system and the blockade of central and cardiac H2 receptors. Handling difficulties most often occur during treatment with antacids. The costs of prophylaxis are lowest for sucralfate. Rational decision analysis shows that pirenzepine given as parenteral medication and sucralfate as enteral medication are the most suitable drugs for stress ulcer prophylaxis.
Stress ulcer bleeding occurs in special risk groups. The main cause of this complication is the loss of protective mechanisms of the gastric mucosa. Preventive measures aim to strengthen the protective mechanisms or to lower the aggressive factors, mainly the gastric acid. Meta-analysis demonstrates that drugs that enhance the protective mechanisms are superior to a regimen that only reduces the secretion of gastric acid. The most important side effects of stress ulcer prophylaxis are related to the inhibition of gastric acid, the blockade of the cytochrome P450 system and the blockade of central and cardiac H2 receptors. Handling difficulties most often occur during treatment with antacids. The costs of prophylaxis are lowest for sucralfate. Rational decision analysis shows that pirenzepine given as parenteral medication and sucralfate as enteral medication are the most suitable drugs for stress ulcer prophylaxis.
Aspiration pneumonitis is one of the major causes of anaesthesia related deaths. H2-receptor antagonists are effective drugs for the prevention of the acid aspiration syndrome (Mendelson’s syndrome). The new long-acting H2-receptor antagonist roxatidine acetate may be the first H2-receptor antagonist which could effectively reduce acid secretion following a single bedtime premedication on the evening before an operation. A prospective controlled randomised double-blind study was conducted in 60 elective patients undergoing gynaecological operations requiring tracheal intubation. 30 patients received oral roxatidine acetate 150mg at 10pm, the other 30 patients received placebo. Immediately after intubation, at 15 minutes and at the end of the operation gastric pH and the volume of the aspirate were measured. In the placebo group, 13 patients (43%) had gastric pH values below the critical value of 2.5, while in the roxatidine acetate group gastric pH values were raised above 2.5 in all but 3 patients (10%) [p < 0.05]. In the roxatidine acetate group pH values were significantly higher than in the placebo group ( p < 0.01). The mean gastric volume in the placebo group was 23.3 ± 27.1ml, compared to 14.5 ± 9.4ml for roxatidine acetate. The 5 highest gastric volumes were observed in the placebo group (max 146ml). A single bedtime oral premedication with roxatidine acetate 150mg ensures a gastric pH above 2.5 until 11am the following day.
