Optimal Dosage of Propofol for Prevention of Increase in IOP during Rapid Sequence Induction with Endotracheal Intubation / 대한마취과학회지

BACKGROUND: Operations for patients with eye injuries frequently require rapid sequence induction of general anesthesia with succinylcholine (Sch), but Sch as well as endotracheal intubation produce increases in intraocular pressure (IOP). The purpose of this study was to examine whether the increase in dosage of propofol from a usual dosage would prevent the increase in IOP due to endotracheal intubation with Sch during a rapid sequence induction of general anesthesia. METHODS: Changes in IOP were measured in three groups of 15 patients each. The patients randomly received thiopental 5 mg/kg (group 1, n = 15), propofol 2.5 mg/kg (group 2, n = 15) or propofol 3.0 mg/kg (group 3, n = 15), followed by Sch 1.0 mg/kg and endotracheal intubation. IOP, systolic arterial pressure (SAP) and heart rate (HR) were measured before induction (baseline), just after intubation, 3 minutes and 10 minutes after intubation. RESULTS: IOP and SAP just after intubaton in groups 1 and 2 increased significantly from baseline, but did not increase significantly from baseline in group 3. IOP and SAP at 3 minutes after intubation in group 1 did not decrease significantly from baseline, but decreased significantly from baseline in groups 2 and 3. IOP and SAP at 10 minutes after intubaton in all groups decreased significantly from baseline. HR just after intubaton in groups 1 and 2 increased significantly from baseline, but did not increase significantly from baseline in group 3. HR at 3 minutes and 10 minutes after intubation in all groups did not change significantly from baseline. CONCLUSIONS: The authors concluded that propofol 3.0 mg/kg could prevent the increase in IOP, systolic arterial pressure and heart rate just after intubation during a rapid sequence induction of general anesthesia.

Intraocular Pressure during Mechanical Ventilation with Positive End-Expiratory Pressure under General Anesthesia / 대한마취과학회지

BACKGROUND: The purpose of the present study was to determine the effect of positive end-expiratory pressure on intraocular pressure under general anesthesia. METHODS: Contact tonometer HA-1 (Kowa, Japan) was used to measure the intraocular pressures of 22 subjects at zero end-expiratory pressure and positive end-expiratory pressure of 15 cmH2O under general anesthesia. The data were statistically analyzed by paired t-test. RESULTS: There is no statistically significant difference between intraocular pressure of zero end-expiratory pressure and positive end-expiratory pressure of 15 cmH2O in a population with normal basal ocular tonometry. CONCLUSIONS: Mechanical ventilation with positive end-expiratory pressure of 15 cmH2O under general anesthesia dose not present a clinically important significant risk for intraocular pressure increase in a population with normal basal ocular tonometry.