Hypotension

Troubleshooting

Troubleshooting hypotension in the field:

• BVM: If bag-valve-mask for manual ventilation fails, verify connections, check battery, try alternate equipment. Available sizes: Adult (1500mL), Pediatric (500mL), Infant (250mL)
• Pulse oximeter: If measures spo2 via infrared absorption through capillary bed fails, verify connections, check battery, try alternate equipment. Available sizes: Finger clip, Earlobe, Pediatric wrap
• Waveform capnograph: If measures end-tidal co2 continuously with waveform display fails, verify connections, check battery, try alternate equipment. Available sizes: Mainstream (inline), Sidestream (sampling)

Clinical Significance

In prehospital care, understanding hypotension can mean the difference between a positive patient outcome and a critical miss. A construction worker stung by wasps, developing urticaria, stridor, and hypotension. Anaphylaxis: epinephrine 0.3mg IM, IV fluids, diphenhydramine, albuterol for bronchospasm.

Related pharmacology: epinephrine at 1:10,000 1mg IV/IO q3-5min (cardiac arrest), 1:1,000 0.3mg IM (anaphylaxis), indicated for Cardiac arrest, anaphylaxis, severe asthma.

Safety Considerations

Field safety for hypotension includes scene assessment before patient contact. Ensure BSI (body substance isolation) precautions are in place. PPE selection depends on the mechanism and suspected pathogens. Gloves are the minimum; add mask and eye protection for splash risk, N95 for airborne pathogens.

Never approach a scene involving hazardous materials, violence, or structural instability without proper resources and clearance from incident command.

Differential Diagnosis

When assessing hypotension, use structured assessment tools to differentiate between possible causes:

Glasgow Coma Scale: Components: Eye opening (1-4), Verbal response (1-5), Motor response (1-6). Scoring: 3-15, 8 or less = severe, 9-12 = moderate, 13-15 = mild.

OPQRST: Components: Onset, Provocation, Quality, Radiation, Severity, Time. Scoring: Pain assessment mnemonic.

Exam Focus Areas

On the Nremt Emt, Nremt Paramedic, Medical Assistant exam(s), questions about hypotension typically test:

1. Recognition of signs and symptoms requiring immediate intervention
2. Assessment findings that differentiate between similar presentations
3. Correct medication selection, dosing, and route of administration
4. Appropriate transport decisions and hospital notification criteria

Historical Context

The modern EMS system in the United States traces to the 1966 "Accidental Death and Disability" white paper (NAS/NRC). Understanding of hypotension has advanced significantly with evidence-based protocols. The NREMT, founded in 1970, standardized certification levels. Current ACLS and PALS guidelines are updated every 5 years by the AHA based on the International Liaison Committee on Resuscitation (ILCOR) evidence review.