Effect of Fosaprepitant on Motor Evoked and Somatosensory Evoked Potentials Under General Anesthesia

The purpose of this study is to determine if intravenous fosaprepitant can interfere with nervous system monitoring signals in patients having surgery under general anesthesia. This medication has numerous effects on the sensory nerve transmission which can theoretically have effects on the ability to accurately measure somatosensory evoked potentials.

The purpose of this study is to determine if intravenous fosaprepitant can interfere with nervous system monitoring signals in patients having surgery under general anesthesia. Fosaprepitant is a drug commonly used to prevent post-operative nausea and vomiting, and works by inhibiting "substance P", which is found in the brain and spinal cord. Theoretically, fosaprepitant could interfere with nervous system recordings because of its effect on substance P,but it is not known if this actually occurs. The drug will be given after the patient has been anesthetized but before surgical incision so that if there are any changes on the intraoperative neuromonitoring signals they can only be attributed to fosaprepitant. If fosaprepitant alters intraoperative neuromonitoring signals during surgical procedures under general anesthesia, it would be important because anesthesiologist's who administer this drug would want to give it at the beginning of surgery when changes in intraoperative neuromonitoring signals would be unlikely to mean that these changes were due to surgical damage to the nervous system.

A single group of up to 50 patients will be administered a standard dose of fosaprepitant 150 mg IV after induction of anesthesia. A standard neuromonitoring setup utilizing motor evoked potentials, and somatosensory evoked potentials will be used as indicated for the type of surgery. After baseline neuromonitoring measurements have been made, but prior to surgery starting, we will administer the fosaprepitant to determine if there are any effects on the motor evoked potentials or somatosensory evoked potentials measurements.

Neuromonitoring modality utilized during surgical procedures potentially affecting sensory component of central and peripheral nervous system. SEPs are the electrical signals generated by the nervous system in response to somatosensory stimuli - typically through electrical stimulation of the median nerve. SEPs are read on the skull with electroencephalography (EEG). SEPs was recorded using a 4-channel EEG system at baseline (predose) and regularly after study drug administration.

Neuromonitoring modality utilized during surgical procedures potentially affecting sensory component of central and peripheral nervous system. SEPs are the electrical signals generated by the nervous system in response to somatosensory stimuli - typically through electrical stimulation of the median nerve. SEPs are read on the skull with electroencephalography (EEG). SEPs was recorded using a 4-channel EEG system at baseline (predose) and regularly after study drug administration.

Neuromonitoring modality utilized during surgical procedures potentially affecting sensory component of central and peripheral nervous system. SEPs are the electrical signals generated by the nervous system in response to somatosensory stimuli - typically through electrical stimulation of the median nerve. SEPs are read on the skull with electroencephalography (EEG). SEPs was recorded using a 4-channel EEG system at baseline (predose) and regularly after study drug administration.

Neuromonitoring modality utilized during surgical procedures potentially affecting sensory component of central and peripheral nervous system. SEPs are the electrical signals generated by the nervous system in response to somatosensory stimuli - typically through electrical stimulation of the median nerve. SEPs are read on the skull with electroencephalography (EEG). SEPs was recorded using a 4-channel EEG system at baseline (predose) and regularly after study drug administration.

Neuromonitoring modality utilized during surgical procedures affecting motor component of central and peripheral nervous system. MEPs are generated when stimulation of the brain on the motor cortex (with Transcranial Magnetic Stimulation [TMS]) causes the spinal cord and peripheral muscles to produce neuroelectrical signals. MEPs are typically measured in the hand muscles.

Inclusion Criteria: Having a surgical procedure requiring general anesthesia, having a surgical procedure where neuromonitoing with somatosensory evoked potentials and motor evoked potentials neuromonitoring is requested by the surgical team Exclusion Criteria: Patient refusal, allergy to the drug or any of its excipients, pre-operative motor or sensory deficit

There is a plan to make IPD available only to members of the research team involved in this project. All patient identifying information will be removed from all data as it is collected to protect patient privacy.