Spinal fusion surgery involves permanently joining two or more vertebrae to stabilize the spine and relieve chronic back pain.

An AV fistula is a surgical connection between an artery and a vein, typically in the arm, used for hemodialysis.

Spirometry is a lung function test that measures how much air you can inhale and exhale, and how quickly you can do it.

Wear loose clothing, avoid heavy meals or intense exercise before the test, and follow any specific instructions from your doctor.

No, spirometry is non-invasive and painless. You will be asked to breathe into a device, which may feel slightly uncomfortable but is not painful.

The test itself takes about 15-30 minutes. Results are usually available immediately or within a few hours.

The frequency depends on your health conditions and doctor’s recommendations. It may be performed regularly for ongoing monitoring or as needed for diagnosis.