Propofol(2, 6-diisopropylphenol) represents a new class of intravenous anesthetic agent, being chemically unrelated to barbiturate, steroid or eugenol agents. It has been reported as a suitable induction agent for short procedures and day case
surgery
due to its property of rapid induction and recovery from anesthesia. Induction of anesthesia with propofol 2.0~2.5mg/kg frequently causes decreasing blood pressure and causes apnea that may last 60s or more. And it is well recognized that
propofol
may
causes pain on injection when administered intravenously.
In the present study, we evaluated the hemodynamic and SpO2 changes after propofol injection and the dose-responses to the loss of verbal command response, eyelid reflex and trapezius reflex in premedicated patients. Also we assessed the degree
of
pain
on injection.
Patients were divided into five groups with the doses of 1.0, 1.2, 1.5, 2.0, and 2.5 mg/kg(group 1, 2, 3, 4 and 5, respectively). The systolic, diastolic blood pressure, heart rate and SpO2 were measured after 60 seconds propofol injection in all
the
patients. And response, to verbal command, eyelid and trapezius reflex and pain complaint were checked.
The systolic and diastolic blood pressure were mostly decreased(17.34 and 21.92%) in group 5(propofol 2.5mg/kg)(p<0.05). Heart rate was increased 10% in group 4 and 5(p<0.05) There was a dose-dependent decreasing tendency of blood pressure and
increasing tendency of heart rates. SpO2 was also more reduced in group 4 and 5(p<0.05). The overall incidence of pain on injection was 47% of the injection sites. The incidence of pain was highest on the dorsum of hand(23%). Also, the degree of
pain on
injection was severe on the dorsum of hand. The value of ED50 and ED95 for loss of verbal command response, eyelid reflex and trapezius reflex were 0.81, 1.35, 1.20, 2.02, 1.91 and 3.60 mg/kg. We concluded that the ED95 for loss of eyelid reflex
is
2.02
mg/kg and it is a sufficient dosage to induction of anesthesia in premedicated patients with little significant hemodynamic changes.
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