01Approach to the Critical Patient/attcp66

Immediate stabilization and high-risk triggers

›Time-critical priorities

›Airway compromise

›If airway risk, airway support and escalation

›If hypoventilation, bag-valve-mask ventilation

›Circulation instability

›If SBP <90 mm Hg or shock index >1, resuscitation bay

›If ongoing chest pain, acute coronary syndrome pathway

›If severe dyspnea or hypoxia, pulmonary embolism pathway

›If active GI bleeding, hemorrhage pathway

›Neurologic emergency

›If persistent focal deficit, stroke pathway

›If prolonged altered mental status, broaden differential

›Dangerous arrhythmia

›If VT, VF, or unstable SVT, ACLS algorithm

›If bradycardia with instability, ACLS bradycardia algorithm

›Immediate bedside checks

›Glucose

›If <3.0 mmol/l, dextrose therapy

›If >20 mmol/l with dehydration, hyperglycemic emergency pathway

›12-lead ECG within 10 minutes

›New ischemia

›High-grade AV block

›Pre-excitation

›QTc prolongation

›Brugada pattern

›Ventricular paced rhythm with symptoms

›Continuous cardiac monitoring

02History/hx77

Event characterization

›Episode features

›Context and activity

›Exertional

›Supine

›Postural change

›Prolonged standing

›Heat exposure

›Prodrome

›Nausea

›Diaphoresis

›Warmth

›Visual dimming

›Palpitations

›Witnessed description

›Sudden collapse without prodrome

›Duration of LOC

›Abnormal movements

›Cyanosis

›Snoring respirations

›Recovery phase

›Immediate return to baseline

›Post-event confusion

›Persistent symptoms

›Injuries

›Head strike

›Facial trauma

›Anticoagulant use at time of fall

03Physical Exam/exam45

Vital signs and orthostatic assessment

›Hemodynamic assessment

›Supine HR and BP

›Persistent hypotension

›Relative bradycardia

›Standing HR and BP

›Orthostatic hypotension criteria

›Postural tachycardia pattern

›Temperature

›Fever as alternate diagnosis trigger

›SpO2

›Hypoxemia as PE or pulmonary trigger

Cardiovascular and volume status

›Cardiovascular exam

›Heart sounds

›Harsh systolic murmur

›Fixed split S2

›New murmur

›JVP and peripheral edema

›Volume overload signs

›Elevated JVP with hypotension

›Pulse exam

›Pulse deficit

›Irregularly irregular rhythm

›Volume status exam

›Mucous membranes

›Capillary refill

›Skin turgor

04Differential Diagnosis/ddx58

Life-threatening causes

›Immediately dangerous etiologies

›Cardiac arrhythmia

›Ventricular tachycardia

›High-grade AV block

›Sick sinus syndrome with pauses

›Acute coronary syndrome

›STEMI equivalent patterns

›NSTEMI with malignant arrhythmia

›Pulmonary embolism

›Massive or submassive

›Hypoxemia or RV strain pattern

›Aortic dissection

›Chest or back pain

›Pulse deficit

›Cardiac tamponade

›Hypotension

›JVP elevation

›Severe hemorrhage

›GI bleeding

›Ectopic pregnancy

›Subarachnoid hemorrhage

›Thunderclap headache

›Neck stiffness

Common benign or intermediate causes

›Non-life-threatening syncope categories

›Vasovagal syncope

›Prodrome with nausea and diaphoresis

05Laboratory Tests/lt40

Targeted ED labs

›Core labs by scenario

›Pregnancy test for people who can become pregnant

›Ectopic pregnancy risk stratification

›Imaging pathway trigger

›Hemoglobin for bleeding concern

›Trend if ongoing loss suspected

›Transfusion thresholds by clinical status

›Electrolytes for arrhythmia risk

›Potassium abnormalities

›Magnesium abnormalities

›Creatinine and eGFR for contrast planning

›CT angiography feasibility

›Medication dosing implications

›High-sensitivity troponin for ischemia concern

›Chest pain

›ECG ischemia

›Known CAD with concerning features

›BNP or NT-proBNP for heart failure concern

›Dyspnea

›Volume overload signs

Point-of-care and bedside tests

›Bedside tests

›Capillary glucose

›Hypoglycemia confirmation

›Hyperglycemia with dehydration trigger

›Venous blood gas when shock or respiratory concern

›Lactate for hypoperfusion

06Diagnostic Tests/dt70

Scoring Systems

›Risk stratification tools

›Canadian Syncope Risk Score

›ED diagnosis elements

›Vasovagal predisposition

›Cardiac syncope features

›Clinical features

›SBP in ED

›History of heart disease

›ECG features

›QRS axis abnormality

›QRS duration prolongation

›QTc prolongation

›Biomarkers

›Elevated troponin

›Outputs

›30-day serious adverse event risk estimate

›Disposition support adjunct

›San Francisco Syncope Rule

›CHF history

›Hematocrit low

›Abnormal ECG

›Shortness of breath

›SBP <90 mm Hg

›Use limitations

›Clinical gestalt integration requirement

›Local validation variation

›Not a replacement for ECG interpretation

07Disposition/dispo48

Admission and monitoring criteria

›Higher level of care triggers

›Abnormal ECG suggestive of arrhythmia or ischemia

›New AV block

›Ventricular tachyarrhythmia evidence

›Ischemic changes

›Structural heart disease with syncope

›Aortic stenosis suspicion

›HCM suspicion

›Persistent hypotension or recurrent syncope in ED

›Ongoing IV fluid requirement

›Pressor requirement

›Significant anemia or active bleeding

›Transfusion need

›Endoscopy pathway

›PE, ACS, dissection, or tamponade concern

›Immediate specialty consultation

›Transfer if capability mismatch

›Observation unit appropriateness

›Intermediate risk without clear serious diagnosis

›Telemetry for 6-24 hours depending on risk

›Repeat ECG if symptoms recur

›Ambulatory monitoring planning

›Patch monitor

›Event recorder

Discharge criteria

›Safe discharge features

›Clear vasovagal or orthostatic mechanism

08Treatment/t69

General supportive care

›Supportive measures

›Supine positioning

›Legs elevated for suspected vasovagal or orthostatic component

›Reassessment of perfusion markers

›IV access

›Two large-bore lines if hemorrhage or shock concern

›Blood products pathway if indicated

›Fluids for suspected hypovolemia

›Isotonic crystalloid bolus 500-1000 ml

›Reassessment after each bolus

›Medication review adjustments

›Hold contributing antihypertensives when appropriate

›Hold diuretics if volume depletion suspected

Arrhythmia-directed therapy

›Bradycardia with instability

›Atropine protocol

›Atropine IV 1 mg

›Repeat every 3-5 minutes

›Maximum 3 mg

›If ineffective, transcutaneous pacing

›Sedation and analgesia if time allows

›Pads placement and capture confirmation

›If pacing not available or bridging, catecholamine infusion

›Epinephrine infusion 2-10 micrograms/min

›Dopamine infusion 5-20 micrograms/kg/min

›Tachyarrhythmia with instability

›Synchronized cardioversion

09Special Populations/sp43

Pregnancy

›Pregnancy considerations

›Physiologic changes

›Lower systemic vascular resistance

›Increased plasma volume

›Supine hypotensive syndrome in later gestation

›Dangerous pregnancy causes

›Ectopic pregnancy

›Hemorrhage

›Pulmonary embolism

›Medication safety

›Avoid teratogenic antiarrhythmics when alternatives exist

›Anticoagulation selection with obstetric input

›Imaging considerations

›Ultrasound-first strategy when feasible

›Radiation risk-benefit documentation

Geriatric

›Older adult considerations

›Higher prevalence of cardiac syncope

›Conduction disease

›Structural heart disease

›Polypharmacy effects

›Orthostatic hypotension from antihypertensives

›Bradycardia from beta-blockers

›Injury risk

›Lower threshold for head imaging when trauma and anticoagulation

›Falls assessment integration

›Autonomic dysfunction

10Background/b34

Epidemiology

›Frequency and impact

›Common ED presentation

›High revisit rates in selected populations

›Significant resource utilization

›Age distribution

›Bimodal peaks in youth and older adults

›Higher adverse event risk with increasing age

Pathophysiology

›Mechanistic categories

›Reflex syncope

›Increased vagal tone

›Vasodilation with relative bradycardia

›Orthostatic hypotension

›Inadequate autonomic compensation to standing

›Volume depletion contribution

›Cardiac syncope

›Abrupt drop in cardiac output from arrhythmia

›Fixed obstruction limiting output augmentation

›Cerebral perfusion threshold

›Global hypoperfusion mechanism for LOC

›Rapid recovery after perfusion restoration

Therapeutic Considerations

›Management principles

›Identify high-risk cardiac etiologies early

›ECG-centered evaluation

›Telemetry when indicated

›Avoid low-yield testing in low-risk presentations

11Patient Discharge Instructions/pdi23

Copy discharge instructions

›Discharge guidance

›Likely cause explanation

›Vasovagal or orthostatic pattern if applicable

›Trigger avoidance strategies

›Hydration and salt guidance when appropriate

›Increased fluid intake unless contraindicated

›Slow position changes from lying or sitting

›Activity and driving

›Avoid driving until cleared if unexplained syncope

›Avoid climbing ladders or heights until follow-up

›Return to ED immediately

›Chest pain

›Shortness of breath

›Recurrent fainting

›Palpitations preceding faint

›Severe headache

›Weakness, numbness, facial droop, speech trouble

›Black or bloody stools

›Persistent vomiting

›Follow-up plan

›Primary care within 1 week

›Cardiology within 1-2 weeks if abnormal ECG or risk factors

›Ambulatory rhythm monitoring pickup instructions if arranged

12References/r18

Guidelines and evidence sources

›Major guidelines

›ACC/AHA/HRS Guideline for the Evaluation and Management of Patients With Syncope (Class I, IIa, IIb framework)

›ECG recommended in initial evaluation (Class I)

›Targeted testing strategy (Class I)

›European Society of Cardiology (ESC) Syncope Guidelines

›Reflex vs orthostatic vs cardiac classification

›Risk stratification and observation pathways

›ACEP Clinical Policy on Syncope

›History, physical exam, and ECG as core evaluation (ACEP Level A)

›Admission for high-risk features support (ACEP Level B)

›Limited role for routine neuroimaging without focal deficit (ACEP Level B/C depending on scenario)

Decision tools and validation studies

›Risk tools

›Canadian Syncope Risk Score derivation and validation studies

›30-day serious adverse event outcome focus

›ECG and troponin integration

›San Francisco Syncope Rule studies

›External validation heterogeneity

›Adjunctive use only

Evidence & Review

Evidence & Review