Intraocular pressures in children during isoflurane and halothane anesthesia

The effects of isoflurane and halothane on intraocular pressure (IOP) were studied in 28 children. Measurements were made during spontaneous ventilation and at a various levels of reduced PaCO2 achieved by controlled ventilation. Control IOP values were determined prior to anesthesia following premedication with chloral hydrate, pentobarbital, pentobarbital with meperidine. At roughly equivalent levels of anesthesia, mean IOP values during spontaneous ventilation ranged frm 16.3 to 17.6 torr for each anesthetic. These values were significantly less (P less than 0.01) than control values only in those patients receiving chloral hydrate who did not cooperate. In contrast, no significant change in IOP was found in more sedated and cooperative patients who received pentobarbital and meperidine. Moderate hypocarbia and hypercarbia over a range of PaCO2 greater than 42 torr had little influence on IOP. We conclude that IOP's during isoflurane and halothane anesthesia do not differ significantly from IOP in the sedated, cooperative, healthy pediatric patient.