Basic Concepts

Jaime Gasco and Aristedes Koutrouvelis

What is “time out”?

A preoperative time when verification of the patient, procedure, and surgery site occurs. It involves all OR personnel, including the patient, the surgeon, the anesthesiologist, and the OR circulating nurse.

What does it attempt to prevent?

Serious reportable events (SREs)

What are SREs?

• Wrong-side surgery (most common)

• Wrong operation

• Wrong patient

• Wrong part of the body

Has this been scientifically proven to decrease events?

What are the bases of general anesthesia?

• Hypnosis (induction agents and maintenance agents)

• Muscle relaxation (muscle relaxants and inhalation agents)

• Analgesia (pain relief and suppression of reflexes)

Induction, maintenance, and emergence Note: Patients with difficult airways may have intubation without induction per se (e.g., fiberoptic intubation under local anesthesia).

Which periods are most prone to variations in hemodynamic and respiratory status?

Induction and emergence (especially induction)

What are the effects of hyperventilation during anesthesia?

Decrease CO₂, CBF, and blood volume.

It also decreases the concentration of volatile anesthetics.

True or false: Induction usually occurs prior to intubation.

True. Only in cases of known difficult airway will intubation precede induction (in which case adequate topicalization and appropriate nerve blocks are performed to minimized patient discomfort).

What does induction achieve?

• Depression in protective reflexes

• Adequate hypnosis, muscle relaxation, and analgesia