Clinical Conundrum: Return to High Altitude After Cerebral Venous Sinus Thrombosis.

Luks, Andrew M., Thomas G. DeLoughery, Jeffrey H.

Practice guidelines for the supervising professional: intraoperative neurophysiological monitoring.

The American Society of Neurophysiological Monitoring (ASNM) was founded in 1989 as the American Society of Evoked Potential Monitoring. From the beginning, the Society has been made up of physicians, doctoral degree holders, Technologists, and all those interested in furthering the profession. The Society changed its name to the ASNM and held its first Annual Meeting in 1990.

Use of Posterior Root-Muscle Reflexes in Peripheral Nerve Surgery: A Case Report.

It is well established that a mixed-agent general anesthetic regimen of volatile gas and intravenous anesthetic or total intravenous anesthetic (TIVA) is required to obtain adequate transcranial motor-evoked potentials (TcMEPs) to detect and hopefully prevent injury during brain, spinal cord, and peripheral nerve surgery. But even under ideal general anesthetic conditions, TcMEPs are not always detectable in every muscle monitored, and are prone to anesthetic fade, especially when neuropathic or injured tissue is monitored. TcMEP sensitivity to general anesthesia can be especially problematic during peripheral nerve surgery where there is often only one or a few essential muscles required to provide adequate monitoring; thus, maximum fidelity is essential.

Vasculopathy, Ischemia, and the Lateral Lumbar Interbody Fusion Surgery: Report of Three Cases.

Multi-modal neurophysiologic monitoring consisting of triggered and spontaneous electromyography and transcranial motor-evoked potentials may detect and prevent both acute and slow developing mechanical and vascular nerve injuries in lateral lumbar interbody fusion (LLIF) surgery. In case report 1, a marked reduction in the transcranial motor-evoked potentials on the operative side alerted to a 28% decrease in mean arterial blood pressure in a 54-year-old woman during an L3-4, L4-5 LLIF. After hemodynamic stability was regained, transcranial motor-evoked potentials returned to baseline and the patient suffered no postoperative complications.

Syndrome of acute anxiety among marines after recent arrival at high altitude.

Management of mental health is critical for maintenance of readiness in austere military environments. Emerging evidence implicates hypoxia as an environmental trigger of anxiety spectrum symptomatology. One thousand thirty-six unacclimatized infantry Marines ascended from sea level to the Marine Corps Mountain Warfare Training Center (2,061-3,383 m) for a 30-day exercise.

Anesthesia considerations for monitoring TCMEPs in adults diagnosed with poliomyelitis as children: a case report.

Unlabelled: The use of transcranial motor evoked potentials (TCMEPs) to detect and hopefully prevent injury to the brain, spinal cord, and peripheral nerves intraoperatively has increased greatly in recent years. It is well established that in addition to certain anesthetic agents, patient factors such as advanced age, obesity, diabetes, hypertension, and a collection of neurological and neuromuscular diseases and disorders can greatly reduce or completely eliminate the ability to monitor TCMEPs effectively. One such disease, poliomyelitis (polio), is a highly contagious viral disease that has been mostly forgotten since its near-eradication through vaccination.

Altitude Sickness in Climbers and Efficacy of NSAIDs Trial (ASCENT): randomized, controlled trial of ibuprofen versus placebo for prevention of altitude illness.

Objective: To study the effectiveness of ibuprofen versus placebo in preventing acute mountain sickness (AMS) and high altitude headache (HAH).

Methods: Double-blind, randomized, placebo-controlled trial.

Results: Two hundred ninety-four healthy Western trekkers were recruited on the Everest approach at 4280 m or 4358 m and randomly assigned to receive either 600 mg of ibuprofen or placebo 3 times daily before and during ascent to 4928 m.

Ibuprofen prevents altitude illness: a randomized controlled trial for prevention of altitude illness with nonsteroidal anti-inflammatories.

Study Objective: Acute mountain sickness occurs in more than 25% of the tens of millions of people who travel to high altitude each year. Previous studies on chemoprophylaxis with nonsteroidal anti-inflammatory drugs are limited in their ability to determine efficacy. We compare ibuprofen versus placebo in the prevention of acute mountain sickness incidence and severity on ascent from low to high altitude.

A paradigm for awake intraoperative memory mapping during forniceal stimulation.

A case report is presented detailing the successful use of awake intraoperative memory testing while using white matter stimulation in order to isolate the fornix tracks involved in memory function. The identification of the white matter tracks of the fornix that were involved in memory function was used to tailor the neurosurgical resection of a third ventricle tumor that was impinging on the fornix in order to successfully preserve memory functioning in the patient.

Prospective, double-blind, randomized, placebo-controlled comparison of acetazolamide versus ibuprofen for prophylaxis against high altitude headache: the Headache Evaluation at Altitude Trial (HEAT).

Objective: High altitude headache (HAH) is the most common neurological complaint at altitude and the defining component of acute mountain sickness (AMS). However, there is a paucity of literature concerning its prevention. Toward this end, we initiated a prospective, double-blind, randomized, placebo-controlled trial in the Nepal Himalaya designed to compare the effectiveness of ibuprofen and acetazolamide for the prevention of HAH.

Acetazolamide 125 mg BD is not significantly different from 375 mg BD in the prevention of acute mountain sickness: the prophylactic acetazolamide dosage comparison for efficacy (PACE) trial.

750 mg per day of acetazolamide in the prevention of acute mountain sickness (AMS), as recommended in the meta-analysis published in 2000 in the British Medical Journal, may be excessive and is controversial. To determine if the efficacy of low-dose acetazolamide 125 mg bd (250 mg), as currently used in the Himalayas, is significantly different from 375 mg bd (750 mg) of acetazolamide in the prevention of AMS, we designed a prospective, double-blind, randomized, placebo-controlled trial. The participants were sampled from a diverse population of (non-Nepali) trekkers at Namche Bazaar (3440 m) in Nepal on the Everest trekking route as they ascended to study midpoints (4280 m/4358 m) and the endpoint, Lobuje (4928 m), where data were collected.

Neurological conditions at altitude that fall outside the usual definition of altitude sickness.

Altitude sickness in its commonly recognized forms consists of acute mountain sickness and the two life-threatening forms, high altitude cerebral and pulmonary edema. Less well known are other conditions, chiefly neurological, that may arise completely outside the usual definition of altitude sickness. These, often focal, neurological conditions are important to recognize so that they do not become categorized as altitude sickness because, besides oxygen and descent, treatment may be vastly different.

Randomised, double blind, placebo controlled comparison of ginkgo biloba and acetazolamide for prevention of acute mountain sickness among Himalayan trekkers: the prevention of high altitude illness trial (PHAIT).

Objective: To evaluate the efficacy of ginkgo biloba, acetazolamide, and their combination as prophylaxis against acute mountain sickness.

Design: Prospective, double blind, randomised, placebo controlled trial.

Setting: Approach to Mount Everest base camp in the Nepal Himalayas at 4280 m or 4358 m and study end point at 4928 m during October and November 2002.

Case report: an ingestion of Hawaiian Baby Woodrose seeds associated with acute psychosis.

An 18 year old male ingested Hawaiian Baby Woodrose seeds (containing the hallucinogen lysergic acid) and required hospitalization for psychotic behavior. This is the second documented case of an acute psychosis ascribed to ingestion of this plant, and it is suggested that Hawaiian Baby Woodrose ingestion should be present in the differential diagnosis when dealing with the acutely psychotic young adult patient.

Efficacy of low-dose acetazolamide (125 mg BID) for the prophylaxis of acute mountain sickness: a prospective, double-blind, randomized, placebo-controlled trial.

The objective of this study was to determine the efficacy of low-dose acetazolamide (125 mg twice daily) for the prevention of acute mountain sickness (AMS). The design was a prospective, double-blind, randomized, placebo-controlled trial in the Mt. Everest region of Nepal between Pheriche (4243 m), the study enrollment site, and Lobuje (4937 m), the study endpoint.

Ginkgo biloba for the prevention of severe acute mountain sickness (AMS) starting one day before rapid ascent.

Previous studies suggest that 5 days of prophylactic ginkgo decreases the incidence of acute mountain sickness (AMS) during gradual ascent. This trial was designed to determine if ginkgo is an effective prophylactic agent if begun 1 day prior to rapid ascent. In this double-blind, randomized, placebo-controlled trial, 26 participants residing at sea level received ginkgo (60 mg TID) or placebo starting 24 h before ascending Mauna Kea, Hawaii.