Burstein et al (1950) induced anaesthesia with various combinations of cyclopropane, ether, N₂O, Pentothal sodium and cocaine in a study of 106 cases. They found substantial increase in pulse rate during laryngoscopy and endotracheal intubation in most of the cases. A deepening of plane of anaesthesia reduced the magnitude of this response CITATION Bur50 \l 1033 (1) . King BD et al (1951) observed the cardiovascular changes with laryngoscopy and tracheal intubation in 46 patients who required GA for surgical procedures.
Laryngoscopy was usually completed in 15 seconds. The average rise of systolic blood pressure, diastolic blood pressure and heart rate (HR) after laryngoscopy and tracheal intubation were 53 mm Hg, 34 mm Hg and 23 bpm respectively. They returned to pre-laryngoscopic level within 5 mins. With deepening of anaesthesia to 2nd or 3rd plane, intubation-induced average rise…
