ASA Standards for Basic Anesthetic Monitoring

Introduction¹

• The ASA standards for basic anesthetic monitoring were developed by the ASA Committee on Standards and Practice Parameters for all general anesthetics, regional anesthetics, and monitored anesthesia care (MAC).
• They do not apply to obstetric labor or pain management cases. Exceptions due to extenuating circumstances should be documented in the patient’s record.

Personnel¹

• Qualified anesthesia personnel must be present in the room throughout the procedure.
• If hazards (e.g., radiation) or emergencies necessitate temporary absence, monitoring provisions must be made and responsibility delegated appropriately.
• In case of an emergency that requires a temporary absence of a qualified anesthesia personnel, clinical judgment must be used to compare the emergency with the condition of the anesthetized patient and in the selection of the designated personnel left to monitor the anesthetized patient.

Objects of Evaluation¹

Oxygenation

• Oxygen concentration of the inspired gas: During general anesthesia, oxygen concentration must be measured via an oxygen analyzer with a low-limit alarm. During regional anesthetics or MAC, proper oxygen flow from the oxygen cylinder or wall oxygen supply must be ensured.
• Blood oxygenation: During all anesthetics, a quantitative assessment of blood oxygenation using pulse oximetry (with audible tone and alarm) must be used.

Ventilation

• Ventilation: During all anesthetics, the adequacy of ventilation must be continually assessed.
  • General anesthesia: evaluate via clinical signs (chest excursion, observation of the reservoir breathing bag, and auscultation of breath sounds), continual end-tidal CO₂ monitoring, and quantitative monitoring of expired gas volume.
  • Endotracheal tube or supraglottic airway placement must be confirmed by clinical assessment and verification of end-tidal CO₂, with ongoing monitoring using continuous end-tidal CO₂ analysis.
  • Mechanical ventilation requires the use of a circuit disconnection alarm with an audible signal.
  • Regional/local anesthesia (no sedation): assess via clinical signs.
  • Moderate/deep sedation: assess via clinical signs and end-tidal CO₂ monitoring.

Circulation

• During all anesthetics, continuous ECG monitoring should be performed from induction until preparation to leave the anesthetizing location.
• Arterial blood pressure and heart rate must be measured at least every 5 minutes.
• During general anesthesia, circulatory function must also be evaluated by palpation of a pulse, auscultation of heart sounds, monitoring of a tracing of intra-arterial pressure, ultrasound peripheral pulse monitoring, or pulse plethysmography/oximetry.

Temperature

• During all anesthetics, the patient’s temperature must be monitored when clinically significant changes in temperature are intended, expected, or suspected.