Hyperbaric Oxygen in the Treatment of Elevated Intracranial Pressure after Head Injury

Abstract

This study is the first to evaluate the effect of hyperbaric oxygen (HBO) on elevated intracranial pressure (ICP) after severe head injury during documented controlled ventilation, hypocapnea, and minute-by-minute ICP data collection. We studied the effect of HBO at 2 atmospheres absolute (ATA) with 100% O₂, on ICP in 2 patients, aged 5 and 21 years. Each patient had diffuse cerebral swelling after blunt trauma and after a gun shot wound, respectively. Both required controlled hyperventilation, osmotic diuretics and ICP monitoring. ICP, mean arterial blood pressure, pulse and atmospheric pressure were recorded at 1-min intervals during 1-hour treatments and for 15 min before and after HBO therapy. Controlled hyperventilation was continued during HBO therapy and PCO, was measured at intervals. Each patient underwent 4 treatments. Data was divided into 5 phases, all at 100% O₂: (1) prior to therapy; (2) during pressurization from 1 to 2 ATA; (3) at 2 ATA; (4) during depressurization from 2 to 1 ATA, and (5) after HBO therapy. During pressurization the mean ICP dropped from 13 to 8 Torr, rising to 14 Torr during HBO therapy at 2 ATA, and to 16 Torr during depressurization to 1 atmosphere, then returning to 12 Torr after HBO therapy. We conclude from this preliminary work that HBO may lower ICP in head-injured patients with diffuse cerebral swelling during the first 15 min, or pressurization phase, of therapy. However, rebound elevations in ICP may occur during or after treatment. No lasting effects of treatment were seen after concluding therapy. The effect of HBO on elevated ICP has not yet been clarified, but deserves further careful study in those patients with severe enough injury to require ICP monitoring.

Neuronal sensitivity to hyperoxia, hypercapnia, and inert gases at hyperbaric pressures

“…However, in each instance, the effects of hyperoxia on the mCNS are attributed to the oxidative effects of ROS (60-63, 70, 107, 205). For example, the mCNS response to hyperoxia can range from a moderate, but reversible change in neural activity (22, 51,142,150,152), possibly with therapeutic benefits for improved neurological function (33,38,158,203), to violent and reversible seizures at higher levels of Pti O 2 (5,60,63), to irreversible motor deficits (and even death) at the highest dosages of hyperoxia (9,12). The use of graded levels of hyperoxia at room pressure (normobaric hyperoxia) and increased ambient pressure (hyperbaric hyperoxia, or HBO 2 ), therefore, is a useful model for studying the wide-ranging effects of oxidative stress on neurological function, which complements more traditional in vitro models of oxidative stress used at normobaric pressure (e.g., Refs.…”

Hyperbaric oxygenation alleviates MCAO-induced brain injury and reduces hydroxyl radical formation and glutamate release

“…The beneWcial eVect of HBO on ischemia-reperfusion brain injury has been evaluated in animal models (Badr et al 2001;Yang et al 2002) and in humans (Helms et al 2005;Rockswold et al 2001;Rusyniak et al 2003;Zhang et al 2003). The observed beneWcial eVects include improvement of brain metabolism (Golden et al 2002), reduction of blood-brain barrier permeability and brain edema (Mink and Dutka 1995), decreasing intracranial pressure (Brown et al 1988), attenuation of inXammatory response (Yin et al 2002), and prevention of apoptotic cell death Yin et al 2003). The search for better understanding of the mechanisms underlying the neuroprotective eVect of HBO continues.…”

Effects of Hyperoxia Exposure on Free Radicals Accumulation in Relation to Ultrastructural Pathological Changes of Diaphragm

“…The risk of hyperoxia was reported to increase with exposure period for over 16 hours of hyperoxia [23,39] in diseases conditions, but in a healthy adult risks are rarely seen before 24 hours of exposure [12,35,40]. Previous data from our laboratory showed an increase in the antioxidant enzyme, GPx, following the exposure to hyperoxia for 24 hr [22].…”