Attenuation of hypotension using phenylephrine during induction of anaesthesia with propofol.
OBJECTIVE
To observe if phenylephrine mixed with propofol can attenuate hypotensive effects of propofol during induction of anaesthesia.


METHODS
A total number of 135 adult ASA-I and ASA-II patients were divided into three groups. (Group A, B and C). All patients were induced with propofol 2.5 mg per kg. In Group A (control group) patients received propofol mixed with 2cc of 0.9% normal saline. Group B (study group) patients received propofol mixed with 2cc of a solution containing phenylephrine 25 microg/cc (total 50 microg); Group C (study group) patients received propofol mixed with 2cc of a solution containing phenylephrine 50 microg/cc (total 100 microg). Haemodynamic variables like systolic, diastolic, mean arterial blood pressure and heart rate were noted. Hypotension was defined as 20% decrease in baseline systolic blood pressure recorded before induction of anaesthesia.


RESULTS
Phenylephrine in a dose of 100 micrograms attenuated the drop in systolic blood pressure. However phenylephrine in a dose 50 micrograms did not effectively prevent anticipated drop in SBP.


CONCLUSIONS
Phenylephrine in doses of 100 micrograms effectively attenuates anticipated hypotension upon induction of general anaesthesia with propofol.
Imran
Muhammad
M
Department of Anaesthesia, Aga Khan University, Karachi.
Khan
Fazal Hameed
FH
Khan
Mansoor Ahmed
MA
D000293:Adolescent; D000328:Adult; D000368:Aged; D018686:Anesthetics, Intravenous / Q000494:pharmacology / Q000627:therapeutic use*; D002316:Cardiotonic Agents / Q000494:pharmacology / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D007022:Hypotension / Q000175:diagnosis / Q000209:etiology / Q000517:prevention & control*; D015994:Incidence; D008297:Male; D008875:Middle Aged; D010656:Phenylephrine / Q000494:pharmacology / Q000627:therapeutic use*; D015742:Propofol / Q000494:pharmacology / Q000627:therapeutic use*; D012307:Risk Factors
D018686:Anesthetics, Intravenous; D002316:Cardiotonic Agents; D010656:Phenylephrine; D015742:Propofol