What are the guidelines for oxygen supplementation in patients?

Oxygen Supplementation Guidelines for Adult Patients

For most acutely ill adult patients, target an oxygen saturation of 94-98%, but for patients at risk of hypercapnic respiratory failure (COPD, morbid obesity, neuromuscular disease, chest wall deformities), target 88-92%. 1

Initial Assessment and Risk Stratification

Determine if the patient is critically ill or at risk for hypercapnic respiratory failure before initiating oxygen therapy. 1

Critical Illness (Immediate High-Flow Oxygen)

For patients with cardiac arrest, shock, sepsis, major trauma, drowning, anaphylaxis, or major pulmonary hemorrhage:

• Start with reservoir mask at 15 L/min immediately 1
• Use highest possible inspired oxygen during CPR until spontaneous circulation returns 1
• Once stable with reliable oximetry, titrate down to maintain SpO2 94-98% 1

Patients at Risk for Hypercapnic Respiratory Failure

Target saturation: 88-92% 1

Risk factors include:

• Severe or moderate COPD (especially with previous respiratory failure or on long-term oxygen) 1
• Severe chest wall or spinal disease (kyphoscoliosis) 1
• Neuromuscular disease 1
• Severe obesity 1
• Cystic fibrosis 1
• Bronchiectasis 1

Initial delivery method:

• 24% Venturi mask at 2-3 L/min OR 28% Venturi mask at 4 L/min OR nasal cannula at 1-2 L/min 1
• Increase Venturi mask flow by up to 50% if respiratory rate exceeds 30 breaths/min 1
• Obtain arterial blood gases within 30-60 minutes 1
• If PCO2 is normal and no history of NIV/IMV, adjust target to 94-98% 1

Standard Acute Hypoxemia (No Risk Factors)

Target saturation: 94-98% 1

For SpO2 < 85%:

• Start with reservoir mask at 15 L/min 1
• Once stabilized, titrate down using nasal cannula or simple face mask 1

For SpO2 85-93%:

• Nasal cannula at 2-6 L/min (preferred) OR simple face mask at 5-10 L/min 1
• Adjust flow to maintain target saturation 1

Condition-Specific Targets

Myocardial Infarction and Acute Coronary Syndromes

• Most patients are not hypoxemic and do not require oxygen 1
• Unnecessary high-concentration oxygen may increase infarct size 1
• If hypoxemic: target 94-98% (or 88-92% if at risk for hypercapnia) 1

Stroke

• High concentrations of oxygen should be avoided unless required to maintain normal saturation 1
• Most stroke patients are not hypoxemic; oxygen may be harmful in non-hypoxemic patients with mild-moderate strokes 1
• If hypoxemic: target 94-98% (or 88-92% if at risk for hypercapnia) 1
• Monitor saturation at least every 4 hours 1

Carbon Monoxide Poisoning

• Give maximum oxygen using bag-valve mask or reservoir mask 1
• Disregard normal or high oximetry readings—pulse oximeters cannot differentiate carboxyhemoglobin from oxyhemoglobin 1

Paraquat or Bleomycin Poisoning

• Avoid oxygen unless SpO2 < 85% 1
• Target saturation: 85-88% (lower than standard) 1
• Supplemental oxygen may worsen lung injury in these specific poisonings 1

Pregnancy and Obstetric Emergencies

• Major trauma, sepsis, or acute illness: target 94-98% 1
• Position above 20 weeks gestation in left lateral tilt or full left lateral position to avoid aortocaval compression 1
• Oxygen therapy may be harmful to the fetus if mother is not hypoxemic 1

Anemia

• Target 94-98% (or 88-92% if at risk for hypercapnia) 1
• Most anemic patients do not require oxygen therapy 1

Hyperventilation/Panic Attacks

• Exclude organic illness first 1
• Patients with pure hyperventilation are unlikely to require oxygen 1
• Rebreathing from paper bag may cause hypoxemia and is NOT recommended 1

Monitoring and Titration

Check oxygen saturation by pulse oximetry in all breathless and acutely ill patients—the "fifth vital sign" 1

• Record SpO2 and inspired oxygen concentration on observation chart 1
• Clinical assessment required if saturation falls ≥3% or below target range 1
• Repeat blood gases 30-60 minutes after any increase in FiO2 1
• If respiratory acidosis develops (pH < 7.35 and PCO2 > 6.0 kPa), seek immediate senior review and consider NIV 1

Weaning and Discontinuation

• Reduce oxygen in stable patients with satisfactory saturation 1
• Discontinue oxygen once patient maintains saturation within or above target range on room air 1
• Leave target range prescription in place for potential future deterioration 1

Critical Pitfalls to Avoid

Never abruptly stop oxygen in patients with hypercapnia—this causes life-threatening rebound hypoxemia 1

• Step down gradually to 28% or 24% Venturi mask or 1-2 L/min nasal cannula 1

Do not give routine oxygen to non-hypoxemic patients with:

• Myocardial infarction (may increase infarct size) 1
• Stroke (may worsen outcomes) 1
• Pregnancy (may harm fetus) 1