Assessing Consciousness AVPU and Glasgow ComaScale
Lesson objectives • Describe the common causes of a deteriorating conscious level. • Describe how to assess a patient with a altered conscious level using the Glasgow coma scale. • Describe the emergency management of a patient with a decreasing conscious level.
Rapid Assessment • A Alert • V responds to Voice • P responds to Pain • U Unresponsive
Glasgow Coma Scale • Assesses patient’s neurological condition • Value range 3 to 15 • 3 totally comatose patient • 15 fully alert patient
Classification of Brain InjuryAccording to Glasgow Coma Scale(GCS) (HICKEY 2003) SEVERE GCS 3-8 MODERATE GCS 9-12 MILD GCS 13-15
Neurological chart • GCS top section • Temperature/BP/pulse/respiratory rate • Pupil size / reaction to light • Limb movement – arms and legs
Eye opening • Spontaneous = 4 • To speech = 3 • To pain = 2 • None = 1
Verbal response • Orientated = 5 • Disorientated = 4 • Monosyllabic = 3 • Incomprehensive = 2 • None = 1
Motor response • Obeys commands = 6 • Localises pain = 5 • Withdrawal to pain = 4 • Flexion to pain = 3 • Extension to pain = 2 • None = 1
Case 1 • 20 year old brought in by ambulance on stretcher/spinal board. • Fell down flight of stairs in night club. • Head injury/laceration scalp. • Loss of consciousness(LOC) approx10-15 mins. • Not speaking but groaning to pain stimuli. • Eyes open to pain stimuli. • When squeeze fingernail attempts to flex arm away from pain.
Signs of basal skull fracture Blood or CSF from nose or ear Periorbital haematoma Mastoid haematoma (Battle's sign) Haemotympanum Radiological evidence of intra-cranial air Radiological evidence of fluid levels in sinuses
Case 2 • 66 year old brought in by ambulance and police. • Sat in a wheelchair. • Found in city centre staggering and unsteady on his feet. • He collapsed whilst with police. • No known injuries. • No loss of consciousness. • Talking to you, confused answers to questions. Eyes open, obeys commands. • What could be going on with this patient?
Causes of a decreased conscious level Hypoxaemia Hypotension Hypercapnia Hypoglycaemia Drugs (sedatives,opiates, overdoses,alcohol) Seizures Head injury Intracranial haemorrhage Cerebral infarction Intracranial infection Hypothermia Hyperthermia Hypothyroidism Hepatic encephalopathy
Early Signs & Symptoms of Raised ICP Deterioration in level of consciousness (LOC) Confusion Restlessness Lethargy Headache Pupillary dysfunction Motor & sensory deficits Cranial nerve palsy
Transient Signs & Symptoms of Raised ICP • Decreased LOC • Pupil abnormalities • Visual disturbance • Motor dysfunction • Headache & vomiting • Aphasia • Changes in respiratory pattern • Changes in vital signs
Late Signs & Symptoms of Raised ICP • Continued deterioration in level of consciousness • Hemiplegia, decortication & decerebration • Alteration in vital signs
Raised ICP Management of Deteriorating Conscious Level • 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. • Measure the blood glucose and treat if level is below 3mmol/l. • Place patient horizontally in the left lateral recovery position.
Summary • A decreased level of consciousness is common in acute illness • Hypoxaemia,hypotension, hypoglycaemia are common causes of coma • A decreased consciousness level may cause airway obstruction and loss of protective airway reflexes • Failure to identify early signs and symptoms of raised intracranial pressure puts the patient at great risk, and opportunity for intervention may be lost • Potential if untreated a respiratory or cardiac arrest • Treatment of a deteriorating consciousness is focused on care of the airway, breathing, circulation disability and exposure
References • Critical care education group, SUHT Oct 2004 • Hickey. J. (2003) 5th Ed The Clinical Practice of Neurological and Neurosurgical Nursing • Intranet – Marsden Manual. Neurological observation • Mooney G (2003) Neurological observations. Nursing times Vol 99/ No 17 • Smith G (2003) Alert manual. University of Portsmouth
Intracranial haemorrhage Cerebral infarction Intracranial infection Hypothermia Hyperthermia Hypothyroidism Hepatic encephalopathy Common causes of a decreased conscious level.
3 parameters • Eye opening • Verbal response • Motor response
Problems of decreased conscious levels • Inability to protect airway – loss of cough and gag reflexes • Increased risk of aspiration • Skin damage • Corneal ulceration