Oxygen¶
Category: Pharmacology Sources: raw/supplemental/emt-b-pharmacology.md, raw/supplemental/patient-assessment-sequence.md Last updated: 2026-04-03
Overview¶
Oxygen is the most commonly administered agent in prehospital care. Although not classified as a "drug" in everyday language, it is administered as a medication in EMS and treated with the same 6 Rights framework. It has no contraindications in the emergency setting — when in doubt, give oxygen.
Key Points¶
- Indications: Hypoxia (SpO2 <94%), respiratory distress, chest pain (suspected ACS), shock, trauma, altered mental status, any patient who may benefit from supplemental O2.
- Contraindications: None in the emergency setting. The concern about high-flow O2 suppressing hypoxic drive in COPD patients is real but does not apply in the acute emergency — treat hypoxia first.
- Delivery devices and flow rates:
| Device | Flow Rate | Approximate FiO2 |
|---|---|---|
| Nasal cannula (NC) | 1–6 LPM | 24–44% |
| Non-rebreather mask (NRB) | 10–15 LPM | 60–90% |
| BVM (with O2) | 15 LPM reservoir | ~100% |
| Simple face mask | 6–10 LPM | 35–60% |
- Device selection: Match device to patient need. Mild hypoxia or low supplemental need → nasal cannula. Respiratory distress, chest pain, shock → non-rebreather. Inadequate breathing or apnea → BVM (see bvm-ventilation).
- 6 Rights: Right patient, right drug, right dose, right route, right time, right documentation. Apply even to oxygen.
- Reassess: After initiating O2, reassess SpO2 and patient comfort. Adjust device or flow rate based on response.
Assessment Relevance¶
Oxygen delivery decisions are made during primary-assessment (inadequate breathing → BVM; distress → NRB) and confirmed during secondary-assessment vital signs (SpO2 <94% → escalate). Trending SpO2 during reassessment verifies whether the chosen delivery method is adequate.
Target SpO2 in most patients: ≥94–98%. In COPD patients with known CO2 retention, target 88–92% to avoid over-oxygenation, but only adjust downward if SpO2 is confirmed above target and the patient is stable.
Procedures¶
See oxygen-administration for the full NREMT-tested skill procedure for nasal cannula and non-rebreather mask application.
General steps: 1. Select appropriate delivery device based on patient condition and SpO2. 2. Check cylinder pressure (minimum 200 psi for use; replace if lower). 3. Open cylinder valve; set flow rate. 4. Attach appropriate mask or cannula. 5. Apply to patient; confirm comfort and seal. 6. Reassess SpO2 after 1–2 minutes. 7. Document flow rate, device, and SpO2 response.
NM Protocol Notes¶
- Oxygen is authorized at EMT-B level in NM without medical direction for any patient with hypoxia, respiratory distress, or suspected ACS.
- NM EMS equipment standards require oxygen cylinders on all BLS units.
- San Juan College EMT program follows NM EMS Bureau protocols — check current version for specific SpO2 thresholds.
NREMT Relevance¶
Oxygen administration is both a standalone skill station (oxygen-administration) and embedded in multiple other stations: - Patient assessment: appropriate O2 device selection is graded - BVM ventilation: O2 supplementation of the BVM is expected - Cardiac arrest: O2 setup is part of resuscitation management - Bleeding control/shock: O2 delivery is part of shock treatment
Common miss: selecting nasal cannula for a hypoxic, distressed patient (should be NRB). Know when to upgrade the delivery device.
Related¶
- oxygen-administration — NREMT skill procedure for O2 delivery
- bvm-ventilation — O2-powered ventilation for inadequate or absent breathing
- primary-assessment — O2 device decision first made here
- secondary-assessment — SpO2 measurement here drives ongoing O2 management
- reassessment — trending SpO2 response to O2 therapy
- bleeding-control-shock — oxygen is part of shock management protocol
Sources¶
raw/supplemental/emt-b-pharmacology.md— Oxygen sectionraw/supplemental/patient-assessment-sequence.md— Breathing and Circulation sections