Loss of Consciousness in Children: Diagnostic Evaluation Tool

Clinical History Assessment

Systematic approach to history taking for a child presenting with loss of consciousness

Physical Examination Guide

Systematic approach to examining a child with loss of consciousness

Diagnostic Approach

Initial Assessment

For a child presenting with loss of consciousness (LOC), the initial assessment should include:

• Detailed history focusing on the circumstances before, during, and after the event
• Complete physical examination with special attention to neurological and cardiovascular systems
• Assessment of vital signs and level of consciousness using age-appropriate scales
• Rapid determination of whether the event was syncopal, seizure, or another cause

Classification of Loss of Consciousness

Different classifications of LOC in pediatric patients:

Type	Definition	Key Features
Syncope	Transient LOC due to cerebral hypoperfusion with spontaneous complete recovery	Preceding lightheadedness, pallor, quick recovery, often positional
Seizure	Paroxysmal event due to abnormal excessive neuronal activity in the brain	Tonic-clonic movements, post-ictal confusion, possible urinary incontinence
Breath-holding Spells	Reflexive LOC in young children triggered by pain, fear, or frustration	Typical age 6-18 months, crying before spell, cyanotic or pallid type
Psychogenic	Non-epileptic events that resemble seizures or syncope with psychological etiology	Atypical movements, closed eyes with resistance, situational triggers
Metabolic	LOC due to metabolic derangements affecting brain function	Hypoglycemia, electrolyte abnormalities, gradual onset, systemic symptoms

Differential Diagnosis

System	Conditions	Red Flags
Cardiovascular	- Vasovagal syncope - Cardiogenic syncope - Cardiac arrhythmias - Structural heart disease - Long QT syndrome	- Exercise-triggered events - Family history of sudden death - No prodromal symptoms - Chest pain - Palpitations before event
Neurological	- Epilepsy - Febrile seizures - Migraine (basilar type) - Increased intracranial pressure - Stroke or TIA	- Post-event confusion >5 min - Focal neurological symptoms - Headache with altered mental status - Repeated episodes with similar pattern - Bladder or bowel incontinence
Respiratory	- Breath-holding spells - Hypoxia - Pulmonary embolism - Severe asthma	- Cyanosis - Respiratory distress - Provocation by crying - Known respiratory condition - Prolonged recovery
Metabolic/Endocrine	- Hypoglycemia - Electrolyte disorders - Adrenal crisis - Inborn errors of metabolism	- Diabetes or known metabolic disorder - Recurrent episodes with fasting - Vomiting and dehydration - Failure to thrive - Unusual odors
Toxicological	- Medication overdose - Drug ingestion - Carbon monoxide poisoning - Alcohol consumption	- Access to medications or toxins - Multiple people affected - Unexplained symptoms in family members - Inconsistent history - Atypical presentation
Psychological	- Psychogenic non-epileptic seizures - Panic attacks - Conversion disorder - Hyperventilation	- Emotional triggers - Atypical movements - Closed eyes with resistance - Normal investigations despite frequent episodes - History of psychological stressors

Laboratory Studies

Consider these studies based on clinical presentation:

Investigation	Clinical Utility	When to Consider
Blood Glucose	Identify hypoglycemia as cause of LOC	All cases, especially with history of fasting or diabetes
Electrolytes, BUN, Creatinine	Assess for metabolic derangements	Vomiting, diarrhea, dehydration, renal disease
Complete Blood Count	Screen for infection, anemia	Fever, pallor, fatigue, recurrent episodes
Toxicology Screen	Identify ingestion or exposure	Unexplained LOC, access to medications/substances
Cardiac Enzymes	Evaluate for myocardial injury	Chest pain, arrhythmias, known heart disease

Advanced Studies

Reserve for specific clinical scenarios:

Investigation	Clinical Utility	When to Consider
Electrocardiogram (ECG)	Identify arrhythmias, conduction abnormalities, structural heart disease	All cases of unexplained LOC, exertional syncope, family history of sudden death
Electroencephalogram (EEG)	Evaluate for seizure activity	Suspected seizure disorder, post-ictal confusion, stereotypical episodes
Neuroimaging (CT/MRI)	Identify structural brain abnormalities	Focal neurological findings, signs of increased ICP, first seizure
Echocardiogram	Evaluate cardiac structure and function	Abnormal ECG, heart murmur, exertional syncope, family history of sudden death
Holter Monitor / Event Recorder	Detect intermittent arrhythmias	Suspected arrhythmia, palpitations, recurrent syncope with normal ECG
Tilt Table Test	Diagnose vasovagal syncope	Recurrent unexplained syncope, postural symptoms
Video EEG Monitoring	Differentiate between seizures and non-epileptic events	Atypical seizure-like episodes, suspected psychogenic events

Diagnostic Algorithm

A stepwise approach to diagnosing loss of consciousness in children:

1. Obtain detailed history from witnesses focusing on before, during, and after event
2. Determine if true LOC occurred versus fall, vertigo, or other event
3. Distinguish between syncope and seizure based on clinical features
4. Perform targeted physical examination including neurological and cardiovascular assessment
5. Obtain ECG for all unexplained first episodes of LOC
6. Consider blood glucose and basic laboratory studies based on presentation
7. Risk stratify into low or high-risk features
8. Pursue advanced testing based on risk stratification and suspected etiology
9. Consider specialist consultation (neurology, cardiology) for atypical or concerning presentations

Management Strategies

General Approach to Management

Key principles in managing loss of consciousness in children:

• Initial stabilization: Ensure airway, breathing, circulation (ABC) are maintained
• Risk stratification: Identify high-risk features requiring urgent intervention
• Directed management: Target underlying cause based on diagnosis
• Family education: Provide guidance on prevention and home management when appropriate
• Follow-up: Arrange appropriate monitoring and reassessment

Acute Management by Presentation

Presentation	Initial Approach	Critical Actions
Actively Seizing	- Maintain airway in recovery position - Administer rescue medication if prolonged (>5 min) - Monitor vital signs - Protect from injury	- Time the seizure - Give benzodiazepine for status epilepticus - Check blood glucose - Consider alternative causes if prolonged
Post-Syncope	- Position supine with legs elevated - Ensure adequate hydration - Monitor vital signs - Observe for recurrence	- Obtain ECG - Review medication history - Check orthostatic vital signs when stable - Screen for precipitating factors
Ongoing Altered Consciousness	- Secure airway - Support ventilation if needed - Establish IV access - Continuous monitoring	- Check blood glucose immediately - Consider naloxone if overdose suspected - Emergency neuroimaging if focal signs - Broad spectrum antibiotics if meningitis/encephalitis suspected
Breath-holding Spell (Resolved)	- Reassurance - Education about benign nature - Preventive strategies	- Distinguish from seizures - Screen for anemia (especially pallid spells) - Advise on behavioral management - Reassure about self-limited course

Management by Specific Etiology

Etiology	Management Approach	Follow-up Recommendations
Vasovagal Syncope	- Hydration education - Recognition of prodromal symptoms - Counter-pressure maneuvers - Avoidance of triggers - Salt supplementation in selected cases	- Routine follow-up if typical features - Education on preventing recurrence - Consider cardiology referral if atypical or frequent
Epilepsy	- Antiepileptic medication if indicated - Seizure action plan - Seizure safety education - Rescue medication teaching - Trigger avoidance (sleep, screens)	- Neurology follow-up - Drug level monitoring if applicable - EEG monitoring as recommended - School management plan
Cardiac Arrhythmia	- Antiarrhythmic medications - Activity restrictions as appropriate - Consider implantable devices for high-risk conditions - Family screening for inherited conditions	- Cardiology follow-up - Holter monitoring - Exercise restrictions as advised - Genetic counseling if hereditary condition
Breath-holding Spells	- Parental reassurance and education - Iron supplementation if anemic - Behavioral strategies - Rarely, atropine for severe cases	- Routine pediatric follow-up - Hemoglobin check if pallid spells - Reassess frequency and severity - Typically resolves by age 5-6 years
Hypoglycemia	- Immediate glucose administration - Identify and address underlying cause - Adjust insulin or feeding schedule if diabetic - Consider metabolic/endocrine workup	- Endocrinology follow-up if recurrent - Blood glucose monitoring plan - Diet and activity counseling - Emergency management education
Psychogenic Events	- Psychological evaluation - Non-judgmental approach - Cognitive behavioral therapy - Stress management techniques - Family therapy if indicated	- Mental health follow-up - Avoidance of unnecessary medical procedures - School reintegration plan - Regular reassessment of symptoms

Preventive Strategies

Type of LOC	Prevention Strategies	Evidence Level
Vasovagal Syncope	- Adequate hydration (2-3L/day) - Regular meals - Recognition of warning signs - Physical counter-maneuvers - Compression stockings	Moderate; several controlled studies support hydration and counter-maneuvers
Seizures	- Medication adherence - Adequate sleep - Stress management - Avoidance of known triggers (flickering lights, fever) - Fever management	High; extensive evidence for medication compliance and lifestyle management
Cardiac Syncope	- Activity restriction as advised - Medication compliance - Avoidance of QT-prolonging medications in LQTS - Emergency action plan - Medical alert identification	High; evidence-based guidelines for management of specific cardiac conditions
Orthostatic Hypotension	- Slow position changes - Hydration - Salt supplementation - Compression garments - Small, frequent meals	Moderate; clinical experience supports, limited pediatric studies

Emergency Protocol and Home Management

Instructions for caregivers:

1. During an event:
   • Place child in recovery position (on side)
   • Do not restrain or put anything in mouth during seizure
   • Time the event
   • Remove hazardous objects from vicinity
   • Stay with child until fully recovered
2. When to call emergency services (911):
   • First-time seizure or unexplained LOC
   • Seizure lasting >5 minutes
   • Repeated seizures without regaining consciousness
   • Difficulty breathing
   • Injury during event
   • Persistent confusion or lethargy
3. Documentation for medical visits:
   • Video recording of events if possible
   • Log of episodes with dates, times, and circumstances
   • Potential triggers noted
   • Duration of unconsciousness and recovery
   • Associated symptoms before, during, and after

Education and Counseling

• Explanation of diagnosis in age-appropriate terms
• Safety precautions based on specific diagnosis
• Activity restrictions as indicated by condition
• School management plan including emergency protocols
• Psychological support for child and family
• Resources including support groups and educational materials

When to Refer

Specialty	Indications for Referral	Urgency
Neurology	- Suspected seizure disorder - Abnormal neurological examination - Recurrent unexplained LOC - Atypical features of seizures or syncope	- Urgent (24-48 hours): First seizure with focal features - Soon (1-2 weeks): Uncomplicated first seizure - Routine: Resolved simple febrile seizure
Cardiology	- Exertional syncope - Family history of sudden death - Abnormal ECG - Syncope with palpitations or chest pain - Recurrent unexplained syncope	- Urgent (24-48 hours): Abnormal ECG, concerning family history - Soon (1-2 weeks): Recurrent typical vasovagal with normal ECG - Routine: Single uncomplicated vasovagal episode
Endocrinology	- Recurrent hypoglycemia - Adrenal insufficiency - Diabetes with poor control - Suspected metabolic disorder	- Urgent (24-48 hours): Severe hypoglycemia without clear cause - Soon (1-2 weeks): Recurrent mild hypoglycemia - Routine: Isolated episode with clear precipitant
Psychology/Psychiatry	- Suspected psychogenic events - Significant anxiety related to diagnosis - Conversion disorder - Comorbid mental health concerns	- Soon (1-2 weeks): Frequent psychogenic events - Routine: Adjustment difficulties to diagnosis - Emergency: Suicidal ideation or severe psychiatric symptoms