Stroke
Dizziness…the good and the ugly…

The differential diagnosis of vertigo can be broken into peripheral and central causes. It is imperative the Emergency Physician consider central causes of vertigo.
Signs/ Symptoms Differentiating Peripheral and Central Vertigo
Peripheral | Central | |
Onset | Sudden or Insidious | Sudden |
Severity of Vertigo | Intense Spinning | Ill-defined, may be severe or less intense |
Prodromal Dizziness | Occurs in up to 25%, often single episode | Occurs in up to 25%, recurrent episodes suggest TIA’s |
Intolerant of head movements/Dix-Hallpike Maneuver | Yes | Varies, but often intolerant |
Associated Nausea/Diaphoresis | Frequent | Variable, but often frequent |
Auditory Symptoms | Points to peripheral causes | May be present |
Proportionality of Symptoms | Usually proportional | Often disproportionate |
Headache/Neck Pain | Unusual | More likely |
CNS signs/symptoms | Absent | Usually present |
Head Impulse Test | Abnormal | Often normal |
Nystagmus | Horizontal | Vertical/direction-changing |
HINTS Testing | Negative | Abnormal in at least 1 out of 3 tests |
Dual antiplatelet therapy (DAPT) improves outcomes in patients with high-risk TIA or minor ischemic stroke

In patients with minor ischemic stroke or high-risk TIA, those who received a combination of clopidogrel and aspirin had a lower risk of major ischemic events but a higher risk of major haemorrhage at 90 days than those who received aspirin alone. However, the relative reduction in recurrent stroke occurred almost entirely during the first week, whereas bleeding events (most of which were not intracranial) were distributed fairly evenly throughout
Oxygen therapy for acutely ill medical patients: a clinical practice guideline

What you need to know
- It is a longstanding cultural norm to provide supplemental oxygen to sick patients regardless of their blood oxygen saturation
- A recent systematic review and meta-analysis has shown that too much supplemental oxygen increases mortality for medical patients in the hospital
- For patients receiving oxygen therapy, aim for peripheral capillary oxygen saturation (SpO2) of ≤ 96% (strong recommendation)
- For patients with acute myocardial infarction or stroke, do not initiate oxygen therapy in patients with SpO2 ≥ 90% (for ≥ 93% strong recommendation, for 90-92% weak recommendation)
- A target SpO2 range of 90-94% seems reasonable for most patients and 88-92% for patients at risk of hypercapnic respiratory failure; use the minimum amount of oxygen necessary

TIA (Transient Ischaemic Attack)
- TIA is defined as a brief episode of neurologic dysfunction with no permanent infarction.
- Head CT noncontrast is not reliable for acute ischemia, but it can find alternative conditions necessitating management. MRI with DWI displays greater diagnostic ability.
- Risk scores that predict future stroke are not reliable when used alone.
- Patients are typically admitted for inpatient management due to this risk of future stroke.