Suspected subarachnoid hemorrhage with nondiagnostic CT and local protocol dependent
CT chest angiography indications
PE concern with moderate to high pretest probability
Aortic dissection concern
Ultrasound
Cardiac POCUS
Pericardial effusion and tamponade physiology
Gross LV function
RV strain patterns with PE concern
IVC assessment
Volume status support
Interpretation limited by ventilation and technique
Lower extremity venous ultrasound
DVT assessment in PE pathway
Adjunct when CT contraindicated
Special Tests
Bedside and monitoring tests
Continuous cardiac monitoring
Telemetry in ED
Capture arrhythmia during symptoms
Orthostatic vitals with symptoms correlation
BP drop and HR response
Interpretation limited by dehydration and medications
Neurologic bedside screening
HINTS only for continuous vertigo syndrome with nystagmus
Not for episodic dizziness or syncope
Seizure evaluation adjuncts
EEG
Consider if recurrent events with seizure features
Limited sensitivity after single event
Tilt table testing
Outpatient evaluation for suspected reflex syncope
Not for acute unstable presentations
ECG
ECG interpretation priorities in syncope
Ischemia and infarction patterns
ST elevation
ST depression
New T wave inversion
Conduction disease
AV block second degree Mobitz II
Complete heart block
Bifascicular block
Channelopathy patterns
Long QT
QTc over 500 ms
Brugada pattern
Preexcitation and tachyarrhythmias
WPW pattern
SVT
Atrial fibrillation
Serial ECG and rhythm capture
Serial ECG approach
Repeat if symptoms recur
Repeat if troponin rising
Rhythm monitoring escalation
Holter or patch monitor outpatient for unexplained recurrent episodes
Implantable loop recorder for recurrent unexplained syncope with concerning features
Assessment
Problem representation and neuro risk framing
Syncope with neurologic concern
Syncope versus seizure versus stroke mimic
Event triggers and prodrome alignment
Recovery time alignment
Injury pattern alignment
Neurologic emergency probability
Persistent focal deficits
Persistent altered mental status
Severe headache pattern
Anticoagulation with head trauma
Cardiac risk co assessment
Exertional syncope
Supine syncope
Abnormal ECG
Known structural heart disease
Risk stratification summary
Short term serious outcome risk
Canadian Syncope Risk Score local protocol dependent
High risk features override low score
Plan
First 5 minutes
Immediate stabilization workflow
Airway support if unable to protect
Oxygen if SpO2 under 94 percent
Cardiac monitor and defibrillator pads if unstable
IV access
Two large bore IV if hypotension or bleeding
Point of care glucose
ECG within 10 minutes
Neuro checks frequency
q15 minutes if concern for deterioration
Immediate neuro escalation triggers
New focal deficit
Worsening mental status
Severe headache progression
Seizure recurrence
Persistent vomiting with headache
Diagnostic sequencing
Initial testing
ECG
Glucose
CBC and electrolytes if indicated
Neuro pathway testing
If persistent focal deficit, activate stroke pathway local protocol dependent
If thunderclap headache, CT head urgent
If anticoagulated with head strike, CT head urgent
Cardiac and PE pathway testing
If chest pain or dyspnea, troponin and chest imaging strategy
If PE concern, use pretest probability tool and D dimer strategy local protocol dependent
Therapeutics and targeted management
Hemodynamic support
IV crystalloid bolus
500 mL to 1000 mL in suspected volume depletion
Reassess BP and symptoms after bolus
Bradycardia management if unstable
Atropine IV 1 mg
Repeat every 3 to 5 minutes
Maximum 3 mg
Transcutaneous pacing if refractory
Tachyarrhythmia management if unstable
Synchronized cardioversion per ACLS
Sedation if time permits
Seizure management if active seizure
Lorazepam IV 2 mg
Repeat once after 5 minutes if ongoing
Levetiracetam IV 60 mg per kg
Maximum 4500 mg
Headache and SAH pathway symptoms
Analgesia choices avoiding hypotension
Antiemetic options with QT caution
Reassessment loop
Reassessment timing and targets
Repeat vitals every 30 to 60 minutes until disposition
Repeat neuro exam after imaging or symptom change
Review telemetry for ectopy or pauses
Orthostatic symptoms after fluids if applicable
Disposition
Level of care and observation logic
ICU criteria
Hemodynamic instability
Malignant arrhythmia
Ongoing seizure activity
Large stroke with airway risk
SAH concern requiring neurosurgical monitoring
Inpatient admission criteria
Persistent focal neurologic deficit
Abnormal neuro imaging
Abnormal ECG with concerning pattern
Elevated troponin with ACS concern
Significant anemia or active bleeding
Syncope during exertion with structural heart disease suspicion
Observation pathway criteria
Unexplained syncope with intermediate risk features
Need for serial ECG or troponin
Need for telemetry monitoring
Discharge criteria
Return to neurologic baseline
No focal deficits
No high risk ECG findings
No serious secondary cause identified
Reliable supervision and follow up
Safe ambulation
Follow up and safety net
Follow up timing
Primary care within 3 to 7 days
Cardiology within 1 to 2 weeks if unexplained or ECG abnormal
Neurology within 1 to 2 weeks if seizure suspected or recurrent events
Discharge Instructions
Copy discharge instructions
Summary
You were evaluated for fainting and possible neurologic causes
Your tests today did not show an emergency cause
Activity
No driving until cleared if seizure is possible or unexplained syncope local protocol dependent
Avoid ladders
Avoid swimming alone
Hydration and triggers
Drink fluids regularly
Avoid prolonged standing
Rise slowly from sitting or lying
Medications
Take medications as prescribed
Do not double dose blood pressure medicines
Return to ED now for
New weakness or numbness
Trouble speaking
Severe headache
Chest pain
Trouble breathing
Recurrent fainting
Seizure like shaking
Confusion that does not resolve
Black or bloody stools
References
Guidelines and decision tools
Syncope evaluation guidelines
European Society of Cardiology syncope guideline 2018
AHA ACC HRS syncope guideline 2017
Emergency medicine syncope guidance
ACEP clinical policy syncope 2007
Updates local protocol dependent
Decision instruments
Canadian Syncope Risk Score derivation and validation 2016 to 2020
San Francisco Syncope Rule 2004
Stroke and seizure references
AHA ASA acute ischemic stroke guideline 2019 update and subsequent updates local protocol dependent
ILAE seizure classification 2017
SymptomDx is an educational tool for medical professionals. It does not replace clinical judgment. Verify all clinical data and drug dosages with authoritative sources.