Medisinsk Lystgass Nippon Gases Scandinavia (Nitrous Oxide)

Nitrous oxide is an inhalational analgesic and sedative used in several procedural settings.

• Procedural sedation: provides rapid onset analgesia and mild sedation for short diagnostic or therapeutic procedures.
• Minor surgery: offers analgesic support during minor surgical interventions, reducing the need for higher‑dose anesthetics.
• Labor analgesia: supplies inhalational pain relief for women during the first stage of labour.

• Inhaled nitrous oxide produces analgesia and sedation primarily by antagonizing N‑methyl‑D‑aspartate (NMDA) receptors, which reduces excitatory neurotransmission, and by enhancing the release of endogenous opioids, thereby modulating pain pathways in the central nervous system.

Nitrous oxide can cause a range of adverse reactions, varying from mild to severe.

Common Side Effects

• Nausea: transient feeling of queasiness during or after inhalation.
• Dizziness: light‑headed sensation that resolves when breathing normal air.
• Headache: mild to moderate headache that usually subsides quickly.
• Euphoria: brief feeling of well‑being or mild intoxication.
• Increased heart rate: mild tachycardia during administration.

Serious or Rare Side Effects

• Hypoxia: reduced oxygen saturation if nitrous oxide is not mixed with adequate oxygen.
• Loss of consciousness: rare, usually associated with prolonged exposure or improper ventilation.
• Severe respiratory depression: can occur in susceptible individuals.
• Vitamin B12 deficiency: prolonged occupational exposure may impair B12 metabolism.
• Malignant hyperthermia trigger: extremely rare but reported in susceptible patients.

Nitrous oxide should be used with careful clinical assessment and appropriate monitoring.

• Patient assessment: evaluate respiratory and cardiovascular status before administration.
• Contraindications: avoid in patients with severe chronic obstructive pulmonary disease, pneumothorax, or recent middle‑ear surgery.
• Monitoring: continuously monitor oxygen saturation, heart rate, and level of consciousness.
• Oxygen supplementation: always deliver nitrous oxide with a minimum of 30% oxygen to prevent hypoxia.
• Scavenging system: use an effective scavenging system to limit occupational exposure for staff.
• Store at ambient temperature: keep cylinders in a well‑ventilated, dry area, protected from direct sunlight and heat.

Nitrous oxide may interact with other agents that affect the central nervous system or vitamin metabolism.

Major Interactions (Avoid)

• Other CNS depressants: concurrent use with potent sedatives or anesthetics can cause profound respiratory depression.
• Volatile anesthetics: combined use may increase the risk of malignant hyperthermia.

Moderate Interactions (Monitor Closely)

• Opioids: may enhance analgesic effect and increase risk of respiratory depression; monitor respiration.
• Benzodiazepines: may potentiate sedative effects; observe level of consciousness.
• Alcohol: additive CNS depression; advise patients to avoid alcohol during treatment.