The 50:50 Nitrous Oxide vs 2% Lidocaine Challenge

The 50:50 Nitrous Oxide Challenge: A Prospective Randomised Trial - Needle, Meet Your Match

The main goal of the project is to assess pain levels and patient comfort during the administration of a 50:50 Nitrous Oxide/Oxygen gas mixture, in comparison to the same parameters under the standard method used at our institution, which includes injecting a local anaesthetic at the site of planned puncture for central venous catheterisation.

Inclusion Criteria:

• Subjects who have not previously received Nitrous Oxide.
• Subjects of both sexes, aged between 18 and 65 inclusive.
• Subjects who have signed informed consent with full disclosure; no study-related procedure may begin until the subject signs the consent form.

Exclusion Criteria:

• Infection at the planned puncture site.
• Pregnancy.
• Intracranial hypertension.
• Vitamin B12 deficiency.
• Hemodynamic instability.
• BMI over 35.
• Glasgow Coma Scale (GCS) score less than 15.
• Presence of chronic pain.
• Neurological disorders.
• Hematologic disorders.
• More than two attempts at venous puncture (Subject Withdrawal Criterion).
• Subject experienced an adverse event requiring early discontinuation (Subject Withdrawal Criterion).
• Withdrawal of consent by the subject (Subject Withdrawal Criterion)