Effect of Combinations of Topical Anaesthesia, Fentanyl, Halothane or N2O on Circulatory Intubation Response in Normo‐ and Hypertensive Patients

Attenuation of the circulatory intubation response was studied using the following combinations: oropharyngeal topical anaesthesia (OTA) + fentanyl 2 micrograms/kg (F2), OTA + 2% halothane with 70% nitrous oxide (H2N2O) or F2 + H2N2O. Firstly, it was observed in 48 normotensive patients that the combinations of OTA + F2 or F2 + H2N2O totally prevented the intubation response; OTA + H2N2O, on the other hand, was less effective. Secondly, the effect of OTA + F2 was studied in 26 hypertensive patients and their 26 normotensive controls of the same age group. The combination prevented the circulatory intubation response also in the hypertensive patients, whose circulatory reactions did not differ from those of the normotensive patients. Nitrous oxide had no beneficial effect on the intubation response.