Method and device for reducing secondary brain injury

Abstract

Disclosed is an apparatus and method for reducing secondary brain injury. The apparatus includes a brain-cooling probe and a control console. The brain-cooling probe cools the brain to prevent secondary injury by cooling the cerebrospinal fluid within one or more brain ventricles. The brain-cooling probe withdraws a small amount of cerebrospinal fluid from a ventricle into a cooling chamber located ex-vivo in close proximity to the head. After the cerebrospinal fluid is cooled it is then reintroduced back into the ventricle. This process is repeated in a cyclical or continuous manner in order to achieve and maintain a predetermined brain ventricle temperature lower than normal body temperature. The apparatus and method disclosed provides effective brain ventricle cooling without the need to introduce extra-corporeal fluids into the brain.

Description

CROSS REFERENCE TO RELATED APPLICATIONS [0001] This application is a Continuation of application Ser. No. 10 / 243,583, filed Sep. 13, 2002, which claims the benefit of Provisional Patent Application Ser. Nr.60 / 322,391 filed 2001 Sep. 14.BACKGROUND [0002] 1. Field of Invention [0003] This invention relates to a method and device for inducing global cerebral hypothermia for the prevention of secondary brain injury from stroke, trauma, or surgery. [0004] 2. Description of Prior Art [0005] Patients suffering from stroke or head trauma, or have undergone invasive brain surgery are at risk from secondary brain injury. Secondary brain injury is a result of the innate healing response of the brain to the original insult caused by several not completely understood mechanisms. Regardless of the specific mechanisms involved, the end result is swelling of the brain caused by edema, which can lead to a critical or terminal rise in intra-cranial pressure. [0006] It has long been known that hypothe...

AI Technical Summary

Problems solved by technology

Patients suffering from stroke or head trauma, or have undergone invasive brain surgery are at risk from secondary brain injury.

Regardless of the specific mechanisms involved, the end result is swelling of the brain caused by edema, which can lead to a critical or terminal rise in intra-cranial pressure.

However, hypothermia has historically been applied systemically, and the depth and duration of hypothermia is limited by the patient's ability to tolerate the therapy.

Systemic hypothermia has been demonstrated to be effective in reducing secondary injury from stroke, trauma, and surgery however, there are several drawbacks to this approach: 1) It takes several hours to lower a patient's body to therapeutic temperatures.

This delay in achieving therapeutic temperatures allows for the progression of irreversible secondary injury to the brain.

2) The practical therapeutic hypothermic temperature and duration is limited by the ability of the patient to tolerate, or survive the therapy.

3) The side effects of systemic hypothermia are frequent and can be life threatening, especially in frail patients.

4) The target of hypothermia therapy is the brain; therefore inducing hypothermia systemically places the patient at undue risk.

5) During the “critical phase” (rewarming period) of hypothermia treatment, there is no effective way to manage a sudden and critical increase in intra-cranial pressure, since re-cooling the body to reverse the increase in intra-cranial pressure takes several hours.

6) Systemic hypothermia poses significant clinical and logistical patient management issues.

Also, since the scientific evidence suggests that hypothermia must be maintained for extended periods of time, there is a great risk that clots will form on the catheters and migrate into the brain leading to episodes of stroke.

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