Effect of Speed of Injection on Induction of Anaesthesia Using Propofol

Abstract

Sixty unpremedicated patients (30 male) were randomly allocated to three groups. They received an induction dose of propofol 2 mg kg-1 over 5, 20 or 60 s to a forearm vein. Anaesthesia was maintained with conventional inhalation anaesthetic agents. Anaesthesia was induced satisfactorily in all 20 of the patients in the 5-s group, in 19 of the patients in the 20-s group and in 18 of the patients in the 60-s group. The rate of injection had a significant influence on induction time. Mean induction time increased from 21.5 to 34.7 and 50.5 s, when injection time was increased from 5 to 20 to 60 s, respectively. Similar induction times were found in male and female patients. There was no significant difference between the groups, in depth of anaesthesia obtained--as assessed by the eyelash reflex. Mean arterial pressure decreased to the same extent in all three groups. Two minutes after induction, mean systolic arterial pressure was reduced by 15.1, 13.5 and 19.3 mm Hg in the 5-, 20- and 60-s groups, respectively, and mean diastolic arterial pressure by 10.3, 13.2 and 13.7 mm Hg. Heart rate changes were insignificant. Apnoea of more than 10 s duration was seen frequently in all three groups, but the results suggest that the incidence was not influenced by the rate of injection. Three patients experienced mild pain at the time of injection. No major adverse reactions occurred during or after anaesthesia.

A Comparative Evaluation of Two Tiva Techniques for Day Care Surgical Procedures– Midazolam and Ketamine Versus Fentanyl and Propofol

“…The induction time was assessed by central fixation of eyeballs after injection ketamine. In Group B, the induction time was 36-42 seconds (The peak effect of propofol is attained at 90-100 seconds as demonstrated by Rolly G, Verseichellen L et al (18) ).…”

Comparative evaluation of propofol-ketamine and propofol-fentanyl for minor surgical procedures

“…Similar dose regimen was used by Saha K et al 8 After giving ketamine and fentanyl, propofol was given in concentration of 1% at the rate of 1 ml/3 sec till loss of eye lash reflex. The rate of injection of propofol was kept constant at approximately 1 ml/sec according to Rolly G et al 9 The total dose of propofol required in group I was 120.75±18.56 mg and in group II 137.75±19.53 mg. The dose of propofol for induction and maintenance of anaesthesia was less in group I.…”

Assessing interaction between dexmedetomidine and propofol

“…Moreover, in the methods, there was no mention of time to start the laryngeal mask airway insertion after completion of propofol administration. After intravenous injection of propofol, the time to reach peak effect is about 100-120 s [3]. It must be emphasized that when anesthesia induction is performed with dexmedetomidine and propofol, clinicians should use the two drugs in such a way that their peak effects appear at the same time, acquiring most effective This comment refers to the article available at…”

“…Moreover, in the methods, there was no mention of time to start the laryngeal mask airway insertion after completion of propofol administration. After intravenous injection of propofol, the time to reach peak effect is about 100-120 s [3].…”