Anoxic brain injury overview

Jump to navigation Jump to search

Anoxic brain injury Microchapters

Home

Patient Information

Overview

Pathophysiology

Causes

Differentiating Anoxic brain injury from other Diseases

Epidemiology and Demographics

Natural History, Complications and Prognosis

Diagnosis

History and Symptoms

Physical Examination

Laboratory Findings

CT

MRI

Echocardiography or Ultrasound

Electroencephalogram

Other Diagnostic Studies

Treatment

Medical Therapy

Surgery

Cost-Effectiveness of Therapy

Future or Investigational Therapies

Case Studies

Case #1

Anoxic brain injury overview On the Web

Most recent articles

Most cited articles

Review articles

CME Programs

Powerpoint slides

Images

American Roentgen Ray Society Images of Anoxic brain injury overview

All Images
X-rays
Echo & Ultrasound
CT Images
MRI

Ongoing Trials at Clinical Trials.gov

US National Guidelines Clearinghouse

NICE Guidance

FDA on Anoxic brain injury overview

CDC on Anoxic brain injury overview

Anoxic brain injury overview in the news

Blogs on Anoxic brain injury overview

Directions to Hospitals Treating Anoxic brain injury

Risk calculators and risk factors for Anoxic brain injury overview

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Overview

Anoxic brain injury or post-cardiac arrest is defined as absence of pulses requiring chest compressions, regardless of location or presenting rhythm. Post-cardiac arrest syndrome is characterized by resumption of spontaneous systemic circulation after prolonged ischemia of whole body.[1] Anoxic or hypoxic brain injury is often seen after cardiac arrest as part of the post-cardiac arrest syndrome. Major efforts are underway to improve "The Chain of Survival" based upon early access to medical care, early defibrillation, early CPR and early hospital care. Therapeutic hypothermia may improve outcomes. Steroids, mannitol, diuresis and hyperventilation have not been documented to meaningfully improve clinical outcomes.

Pathophysiology

There are a variety of factors that contribute to anoxic brain injury. The primary mechanism for injury is a result of a lack of oxygen to the brain, therefore any condition which causes this, such as cardiac arrest or airway obstruction, can cause anoxic brain injury.

Natural History, Complications and Prognosis

Persons with anoxic brain injury are at a high risk of death due to factors such as cardiac arrest, congestive heart failure, pneumonia, and sepsis. There are predictors of survival that have been studied. For example, persons with in-hospital cardiac arrest have a better chance of survival than out-of-hospital arrest, rapid defibrillation improves survival, and VT and VF have a better prognosis than asystole or PEA.

Diagnosis

Physical Examination

Physical examination involves a thorough neurologic evaluation, with a focus on the extent of involvement of the brainstem.

Laboratory Findings

A number of laboratory tests are obtained in order to evaluate the underlying cause of the anoxic brain injury. Common laboratory tests include complete blood count, ABG, electrolytes, cardiac enzymes and serum lactate.

CT

In the early hours and days after anoxic brain injury, there is often diffuse cerebral edema and blurring of the border between the grey and white matter. In some patients there may be discrete infarcts after a few days.

Electroencephalogram

Most often the EEGs of patients in coma after cardiac arrest shows diffuse slowing of both the theta and delta waves, and periodic epileptiform firing. Severe slowing or a flat line appearance is associated with a poor prognosis.

Other Diagnostic Studies

Other pertinent diagnostic studies in anoxic brain injury, include evoked-response testing, and the steps in diagnosing brain death.

References

  1. Neumar RW, Nolan JP, Adrie C, Aibiki M, Berg RA, Böttiger BW; et al. (2008). "Post-cardiac arrest syndrome: epidemiology, pathophysiology, treatment, and prognostication. A consensus statement from the International Liaison Committee on Resuscitation (American Heart Association, Australian and New Zealand Council on Resuscitation, European Resuscitation Council, Heart and Stroke Foundation of Canada, InterAmerican Heart Foundation, Resuscitation Council of Asia, and the Resuscitation Council of Southern Africa); the American Heart Association Emergency Cardiovascular Care Committee; the Council on Cardiovascular Surgery and Anesthesia; the Council on Cardiopulmonary, Perioperative, and Critical Care; the Council on Clinical Cardiology; and the Stroke Council". Circulation. 118 (23): 2452–83. doi:10.1161/CIRCULATIONAHA.108.190652. PMID 18948368.

Template:WH Template:WS