Improved Patient Recovery After Anesthesia With Hypercapnia Hyperpnoea

Inclusion Criteria: * adults * ASA class I-III * both genders * scheduled to undergo eye surgery at the Moran Hospital. Exclusion Criteria: * a history of renal or hepatic disease, * chronic alcohol or drug abuse, * disabling neuropsychiatric disorder, * hypersensitivity or unusual response to other halogenated anesthetics, * pulmonary hypertension, * increased intracranial pressure, * seizure disorder * personal/familial history of malignant hyperthermia. * currently being treated with known hepatic enzyme-inducing drugs (e.g., phenobarbital, dilantin or isoniazid) * or with drugs known to alter anesthetic requirements (e.g., opiates, clonidine, alpha2 agonists, alcohol, anticonvulsants, antidepressants, barbiturates, benzodiazepines or other tranquilizers). * intolerance to non-steroidal anti-inflammatories. * have received general anesthesia within the previous 7 days, * received any investigational drug within the previous 28 days, * participated in a previous isoflurane or desflurane study * Female subjects can be neither pregnant nor breast feeding.