Cerebral gas embolism
The incidence of cerebral gas embolism is estimated at 2.65 cases per 100,000 hospital admissions . As this rarely happens, there are no large studies but rather testimonials in the form of numerous individual case reports. It occurs mainly in connection with a medical intervention such as a surgical act, a puncture, etc. It can occur after a lung biopsy , but also in the heart surgery , after a joint puncture , an endoscopy of the bile ducts , in neurosurgery , when placing a central venous catheter , after lithotrypsia , at a radio with contrast agent of the brain vessels , etc.
They depend on the amount of gas and its location in the brain . If the patient is conscious during the procedure, paralysis, language difficulties, seizures or sudden loss of consciousness occur after 1 to 2 minutes. If the incident occurs during anesthesia, cardiac arrest may occur during the operation or patient may wake up from anesthesia with an epileptic seizure or paralysis as mentioned above . A positive Babinsky sign leads to a worse forecast .
Goal of treatment
Rapid reduction in the accumulation of air in the brain with concomitant oxygenation of brain areas that are no longer supplied with blood, in order to save as much of the brain substance as possible.
There are no controlled studies in the literature for any kinf of treatment. Although different types of treatment have been proposed: hypothermia, retrograde cerebral perfusion, simple administration of oxygen, hyperbaric oxygen therapy is still considered as the treatment of choice. The first positive report on HBO dates from 1975 , there are now more than 100 positive case reports with HBO. Since this is an emergency, hyperbaric oxygen therapy should be performed as soon as possible. According to Blanc et al., Success is greatest if patients are treated within the first 6 hours of the event . In some cases, even late treatment has resulted in improvement or even a healing . In a reference center in Paris, the mortality rate was 21% after a year, there were sequelae in 43% of the survivors. A cure can be expected if HBOT is applied within 7 hours. Interestingly, the brain was X-rayed in 43% of the assigned patients (MRI). This resulted in a 2.5 hour delay in hyperbaric oxygen therapy, resulting in a deterioration in treatment results. Because hyperbaric oxygen therapy is very safe and has no special side effects, some doctors recommend to start HBO without imaging tests .
Practical use of HBOT
The treatment is carried out as an emergency, with for example a 5-hour session under intensive care. Only a few treatments are necessary during the first 24 to 48 hours.