What is the incidence of postoperative nausea in surgical patients after general anesthesia?
Occurs in 20%–30% of surgical patients after general anesthesia
What are the effects of compressive forces on nerves?
Resistence to flow and ischemia, impacting nerves such as the ulnar nerve, brachial plexus, and sciatic nerve
Compressive forces greater than mean capillary pressure (35 mm Hg) lead to these effects.
What is the mean capillary pressure referenced in nerve compression?
35 mm Hg
This pressure is a critical threshold for resistance to flow.
What types of nerves are particularly affected by compressive forces?
- Ulnar nerve
- Brachial plexus
- Sciatic nerve
These nerves are especially susceptible to ischemia due to compressive forces.
What is the impact of vascular tourniquets in orthopedic surgery?
They can produce reversible nerve conduction abnormalities
This effect is particularly noted when tourniquet times exceed 2 hours.
What is the recommended tourniquet time to minimize nerve conduction abnormalities?
Less than 2 hours
Shorter times are advised if comorbidities like diabetes, malnutrition, chemotherapy, or neuropathies exist.
True or False: Tourniquet times of less than 2 hours are generally well tolerated.
True
This is contingent on the absence of comorbid conditions.
What factors may influence the tolerance of tourniquet times?
- Diabetes Mellitus (DM)
- Malnutrition
- Chemotherapy
- Neuropathies
These comorbidities can reduce tolerance to longer tourniquet times.
