Effects of thiopentone, etomidate and propofol on the haemodynamic response to tracheal intubation

Abstract

Summary Tlic licie~r~iod~~riatriic response to traclieal intubation wus compared inThe haemodynamic consequcnces of laryngoscopy and tracheal intubation have been reported for many years'-4 and may be sevcre enough to have scrious myocardial 5 -8 and cerebral efPect~.~ ' ) Scvcral methods have been described to protcct against this r c s p o n~c . '~-'~ It was noted recently that these changes arc attenuated, although not abolished after induction of anaesthesia with propofol.20-23The present study investigated the effects of three induction agcnts. thiopentone, etomidate and propofol, with and without fentanyl. on the haemodynamic response to tracheal intubation. MethodsStudies were carried o u t on 303 patients between 16 and 60 years of age, ASA gradc 1 or 2, who were to undergo surgery that required trachcal intubation. Hypertensive patients or those with knohn allergy to any of thc drugs used were not studied. The protocol also allowed exclusion of the results of any patient who proved difficult to intubate or who coughed during trachcal intubation: there were 12 such patients in the study.The patients were randomly allocated into six groups to receive the following induction agents: thiopentone 4 rng/kg with and without fentanyl 2 pgikg; etomidate 0.3 mg/kg with and without fentanyl 2 pg/kg: and propofol 2.5 mg/kg with and without fentanyl 2 pgikg. All patients received intramuscular premedication with atropine 0.6 mg and papaverctum ]--I .S hours bcforc opcration. The dose of papaveretum varied according to the patients' weight: <SO kg, 10 mg: 50-70 kg. 15 mg; and > 7 0 kg, 20 mg. Procl~dureA conventional four-lead ECG was attachcd on arrival in the anaesthetic room and lead 2 displayed continuously. A strip recorder was used to identify any dysrhythmias. An automatic blood pressure cuff (Dinamap) was attached to one arm and an indwelling cannula inserted into a vein in the other arm for drug administration. Measurements of arterial blood pressure were made 10 minutes. 5 minutes and immediately prior to induction.Fentanyl 2 /@kg (or an appropriate volume of saline) was then injcctcd over 30 seconds. The induction agent was also injcctcd over 30 seconds. one minute after the start of thc fcntanyl injection and immediately after tneasurements had been made. The patient then breathed 70°h nitrous oxidc in oxygen via a Magill system; ventilation was assisted gently if necessary. Suxamethonium 1.5 mgikg was injected during IS seconds immediately after the next nieasurements. one minute after the start of induction, and vcntilation controlled. The trachca was intubated with a cuffcd tube 2 minutes after the start of the suxamcthonium injection and the lungs ventilated with thc same mixture. Measurerncnts were taken immediately prior to laryngo-C.E. Harris, FFARCS.

A Comparative Study of Effect of Propofol, Etomidate and Propofol Plus Etomidate Induction on Hemodynamic Response to Endotracheal Intubation: A RCT

“…Harris et al [20] compared the hemodynamic response to tracheal intubation in 303 patients in whom anesthesia was induced with either thiopentone 4 mg/kg, etomidate 0.3 mg/kg or propofol 2.5 mg/kg with or without fentanyl 2 µg/kg. After propofol alone, there was a significant decrease in arterial blood pressure, which did not increase above control value after intubation.…”

Comparison of Different Cuff Pressure Use with the Supreme Laryngeal Mask Airway on Haemodynamic Response, Seal Pressure and Postoperative Adverse Events: A Prospective Randomized Study

“…With this procedure, we have successfully reduced the stress response to intubation. We noted that MAP and HR values after placement of the SLMA were significantly lower in Group L than in Group N. Haemodynamic response that occurs during intubation is influenced by the depth of anaesthesia (17,18). In the present study, those effects were standardized by using BIS and TOF monitoring to provide similar conditions during SLMA placement in all patients.…”

Comparison of haemodynamic response to laryngoscopy and endotracheal intubation following induction of general anaesthesia with propofol or etomidate

“…However, the adverse effects such as pain on injection, thrombophlebitis and myoclonus have been reduced by using reformulated lipofundin (lipuro) solution and pretreating with fentanyl, an opioid. 1 Etomidate is one of the induction agents which is claimed to be cardiostable and had gained lot of popularity in the past and fell out of use due to adrenocortical suppression. Further studies in the recent years on etomidate have yielded a promising results and it has regained its popularity as a safe anesthetic and more so in sepsis and critically ill patients who are haemodynamically unstable.…”