Volume status evaluation by IVC diameter and pleth variability index in spinal anesthesia

Area of Science:

• Anesthesiology
• Critical Care Medicine
• Cardiovascular Ultrasound

Background:

• Spinal anesthesia (SA) can lead to hypotension, a common complication.
• Predicting hypotension risk is crucial for patient safety during SA.
• Current methods for predicting hypotension may have limitations.

Purpose of the Study:

• To evaluate the efficacy of ultrasound-derived inferior vena cava diameter (IVC-D) and area (IVC-A), along with the pleth variability index (PVI), in predicting hypotension following SA.
• To establish predictive cutoff values for these parameters.

Main Methods:

• A prospective, observational study involving 64 patients undergoing endovenous radiofrequency ablation under SA.
• Measurements of PVI, IVC-D, and IVC-A were taken before SA.
• Patients were categorized into a hypotension group and a non-hypotension group.

Main Results:

• The hypotension group exhibited a higher mean PVI compared to the non-hypotension group.
• The non-hypotension group showed significantly larger mean IVC-D and IVC-A values.
• Identified cutoff values for hypotension risk: PVI > 15% and IVC-A ≤ 2.98 mm².

Conclusions:

• Ultrasound measurements of IVC-D and IVC-A, in conjunction with PVI, are effective and reliable for predicting the risk of hypotension during SA.
• These non-invasive methods can aid in perioperative risk assessment for patients undergoing SA.