LOSS OF CONSCIOUSNESS & ASSESSMENT Sheba Medical Center Acute Medicine Department MATTHEW WRIGHT
OUTLINE Causes Head Injury Clinical Features Complications Rapid Assessment Glasgow Coma Scale Classification
CAUSES Hypoxaemia Hypotension Hypercapnia Hypoglycaemia Drugs (sedatives,opiates, overdoses,alcohol) Seizures Head injury Intracranial haemorrhage Cerebral/Myocardial infarction Intracranial infection Hypothermia Hyperthermia Hypothyroidism Hepatic encephalopathy
SYNCOPE Causes Vasovagal Orthostatic Hypotension Cardiac Disease/Arrhythmias Distinguish true syncope from other causes of loss of consciousness Assessment Detailed History & Physical Examination 12-Lead ECG Echocardiogram Tilt-Test
HEAD INJURY Should be suspected in all trauma cases Classification of Injury Closed type blunt force Penetrating type skull fracture Classification of Pathophysiology Primary Occurs at same time as injury Axonal shearing, disruption and areas of haemorrhage Diffuse or localised brain injury Secondary Occurs later Different forms
CLINICAL FEATURES Loss of consciousness, confusion, drowsiness or amnesia. Convulsions. Severe headache. Irritability (especially in children), personality changes, or abnormal behaviour. Restlessness, clumsiness, or lack of coordination. Hemiplegia (paralysis of one side of the body). Slurred speech or blurred vision. Stiff neck or vomiting. Blood or CSF discharged from nose, mouth, or ears. Changes in the size of the pupil and their reaction to light. Low breathing rate or irregular respiration. Drop in blood pressure may occur or bradycardia and hypertension which reflect the Cushing reflex (an increase in the intracranial pressure leads to an increase in the blood pressure and bradycardia).
HAEMATOMAS Location Vessels Symptoms EPIDURAL Between skull and outer dura mater Middle Meningeal usually also sinuses Lucid interval followed by unconsciousness SUBDURAL Between dura and arachnoid Bridging veins Gradually increasing headache and confusion CT Biconvex lens Crescent shaped
IMAGING Epidural Subdural
SKULL FRACTURES A fracture that extends to the base of the skull is more severe and is likely to cause damage to the cerebellum and inner ear. A depressed fracture may require surgery to repair or replace the damaged skull bone, and to handle the effected brain tissue. A fracture in the vicinity of the forehead, nose, or middle ear may result in a leak of cerebrospinal fluid, and runs the risk of bacterial infection leading to meningitis. Signs of Skull Fracture: Bilateral orbital bruising (panda eyes). Subconjunctival haemorrhage. Blood or CSF discharged from the nose or ears. Battle s sign (bruising over the mastoid process due to fracture of temporal bone).
COMPLICATIONS The direct effect of head injury includes a diffuse neuronal injury or brain laceration. The secondary effects of head injury that increase brain damage include: Intracranial haematoma (subdural, extradural or intracerebral) which causes a localised effect and increases the intracranial pressure. Cerebral oedema which causes an increase in the intracranial pressure. This is a result of a diffuse brain injury. Hypoxia due to airway obstruction or chest trauma. Infection due to a fracture or penetrating head injury. A drop in blood pressure due to blood loss.
RAPID ASSESSMENT A Alert V responds to Voice P responds to Pain U Unresponsive
GLASGOW COMA SCALE Assesses patient s neurological condition 3 Parameters Verbal Response Motor Response Eye Response Value range 3 to 15 3 totally comatose patient 15 fully alert patient
GLASGOW COMA SCALE
GCS INTERPRETATION Every brain injury is different, but generally, brain injury is classified as: Severe: GCS 3-8 (You cannot score lower than a 3.) Moderate: GCS 9-12 Mild: GCS 13-15 Mild brain injuries can result in temporary or permanent neurological symptoms and a neuro-imaging tests such as CT/MRI scan may or may not show evidence of any damage. Moderate and severe brain injuries often result in long-term impairments in cognition (thinking skills), physical skills, and/or emotional/behavioural functioning. LIMITATIONS Factors like drug/alcohol use, shock, or low blood oxygen can alter a patient s level of consciousness. These factors could lead to an inaccurate score on the GCS. The GCS is usually not used with younger children, especially those too young to have reliable language skills. The Pediatric Glasgow Coma Scale is used instead.
GCS
MILD CLASSIFICATION Injury Mechanism: Nonpenetrating Loss of Consciousness < 30 minutes Amnesia < 24 hours GCS: 13-15 Imaging: Negative MODERATE Injury Mechanism: acceleration/deceleration Loss of Consciousness 30min 24 hr Amnesia 24 hr 7 days GCS: 9-12 Imaging: Transient changes SEVERE Injury Mechanism: complex, penetrating Loss of Consciousness > 24 hr Amnesia > 7 days GCS: < 9 Imaging: Positive
INDICATIONS Indications of Skull X-ray in Head Injury: History of a significant injury, impaired consciousness or continuing manifestations. Signs of skull fractures. Scalp lacerations or haematoma. Glasgow coma scale less than 15/15. Neurological signs. Difficulty in assessing a patient because of age, alcohol or drugs. A penetrating head injury. Indications of CT Scan in Head Injury: Signs of skull fractures with Glasgow coma scale less than 15/15 or any neurological sign. Deteriorating Glasgow coma scale (less than 12/15). Neurological signs. Continuing symptoms or emerging signs after admission.
MANAGEMENT Ensure the patient s airway is patent Give high concentration oxygen to ensure good cerebral profusion If ventilation is inadequate, provide assisted ventilation. Ensure intravenous access and prescribe fluids as necessary Reverse any drug induced CNS depression. ECG Measurement Measure the blood glucose and treat if level is below 3mmol/l. Place patient horizontally in the left lateral recovery position.