Is a blood pressure (BP) reading of 90/70 considered hypotension?

Is a Blood Pressure of 90/70 Considered Hypotension?

A blood pressure of 90/70 mmHg is generally not considered hypotension in most adults, as hypotension is typically defined as a systolic blood pressure below 90 mmHg or a mean arterial pressure below 65 mmHg. 1

Standard Definitions of Hypotension

• Hypotension is most commonly defined as a systolic blood pressure (SBP) less than 90 mmHg 1
• Alternative definition includes mean arterial pressure (MAP) less than 65 mmHg at rest 1
• The European Society of Cardiology defines hypotension as SBP <90 mmHg or MAP <65 mmHg 2
• In sepsis management, hypotension is defined as SBP ≤90 mmHg or a decrease ≥40 mmHg from baseline 2

Clinical Significance of BP 90/70

• A BP of 90/70 mmHg is at the borderline of the standard hypotension definition (90 mmHg systolic) 1
• This reading should be interpreted in context of:
  • The patient's baseline blood pressure 1
  • Presence or absence of symptoms 1
  • Clinical circumstances (e.g., acute illness, medication effects) 3

When 90/70 May Be Clinically Significant

• In patients with chronic hypertension, a BP of 90/70 may represent a significant drop from baseline and could be symptomatic 1
• In elderly patients (≥70 years), higher thresholds for hypotension may apply (up to 140 mmHg systolic) 4
• In the context of trauma or acute illness, 90/70 may indicate early shock 5
• When accompanied by symptoms such as dizziness, lightheadedness, or altered mental status 1, 6

Symptoms Associated with Hypotension

• Common symptoms include dizziness, syncope, headache, visual disturbances, nausea/vomiting, or fatigue 1
• Absence of symptoms suggests the BP may be appropriate for that individual 1
• Individual tolerance to low BP varies significantly between patients 2

Special Considerations

• Orthostatic hypotension is defined differently - as a drop in SBP ≥20 mmHg or DBP ≥10 mmHg within 1-3 minutes of standing 1, 7
• In children, hypotension thresholds are age-specific and different from adult values 3
• In heart failure patients, hypotension is sometimes defined with higher thresholds (SBP <90-100 mmHg) 1

Clinical Approach to Borderline BP

• Confirm the reading with proper technique and appropriate cuff size 2
• Check for orthostatic changes by measuring BP in both supine and standing positions 8
• Correlate with symptoms and clinical context 1
• Consider ambulatory blood pressure monitoring if office measurements don't correlate with symptoms 3
• Assess for signs of hypoperfusion even in apparently asymptomatic patients 3

Conclusion

A single BP reading of 90/70 mmHg is at the threshold but not definitively hypotensive by standard definitions. Clinical context, symptoms, and patient-specific factors should guide interpretation and management decisions.