Etomidate vs Propofol-Induction Characteristics

The ideal induction agent for day care surgery should have properties of rapid, smooth induction, better haemodynamic profile, faster recovery and devoid of side effects in the form of pain on injection, involuntary movements, respiratory depression and post-operative nausea/vomiting. Propofol is the drug being used for day care surgeries because of its rapid, smooth induction and faster recovery. But its use is associated with pain on injection (even with added lidocaine), hypotension and respiratory depression. So the need for an agent with better hemodynamic control and lesser side effects was felt. The introduction of etomidate lipuro revolutionised the anaesthesia practice. It possesses many of the properties of an ideal induction agent. This newer formulation of etomidate in lipid emulsion i.e. etomidate lipuro is known to have rapid, smooth induction, haemodynamic stability and lesser side effects than older etomidate with propylene glycol (hypnomidate).

Hence, investigators devised a prospective randomized controlled open trial and compared this newer lipid formulation of etomidate with propofol in terms of - induction time, haemodynamic parameters and side effect profile.

The administration of a suitable drug by intravenous route for induction of anaesthesia has been an important component of anaesthetic management.The ability to deliver safe and effective anaesthesia with minimal side effects and rapid recovery is critically important to ensure safe and early discharge. An ideal intravenous (IV) anaesthetic agent should, have rapid onset, rapid recovery, be without undesirable cardiac and respiratory depression and lesser untoward effects like pain on injection, nausea, vomiting etc.No single drug is ideal.

Propofol (propofol 1%) has a smooth and rapid induction, rapid recovery, cerebro-protective effect but it causes hypotension, bradycardia, respiratory depression pain on injection.Etomidate is a hypnotic agent causing minimal histamine release and very stable hemodynamic profile. In the present study, investigators evaluated the induction characteristics and side effect profile of this newer lipid formulation of etomidate and compared it with propofol in same lipid formulation.

Material and Methods: Hundred ASA I \& II patients in the age group 18-60 yrs, scheduled for dilatation and curettage procedure were randomly allocated in two groups based on induction agent Etomidate lipuro or Propofol.

Both groups received intravenous midazolam 0.02mg /kg and fentanyl 2 µg /kg as premedication. After induction with the desired agent titrated to bispectral index Entropy 40, the time to achieve BIS values to 40 (BIS 40 time) were measured. Heart rate, mean arterial pressures were recorded at baseline, induction and upto 10 minutes. Patients were asked for pain at the injection site, postoperative nausea and observed visually for myoclonus, apnea and thrombophlebitis.

Eligibility Criteria:
Inclusion Criteria:

* ASA I and II Female patients
* Elective Medical Termination of Pregnancy (MTP) surgery

Exclusion Criteria:

* Hemo-dynamically unstable patients
* Allergic to egg protein
* Patients with epilepsy