Many previous studies have investigated the ability of various methods such as passive leg raising test , and inferior vena cava collapsibility index in predicting post-spinal hypotension, but none of them have succeeded in obtaining a good predictive value.

Our study aims to combine the passive leg raising test with the inferior vena cava distensibility index to aid in predicting post-spinal hypotension in elderly undergoing infra-umbilical surgeries.

Inclusion Criteria:

• 1. 65 years of age or more. 2. ASA score I & II. 3. Patients are scheduled for infra umbilical surgeries under spinal anesthesia.

Exclusion Criteria:

• Negative consent. Pre-existing hypertension Diabetes mellitus or autonomic neuropathy (patients diagnosed with autonomic neuropathy or having suggestive symptoms such as orthostatic hypotension, syncopal attacks, decreased sweating, and urinary incontinence) Emergency operations Absolute contraindications or failure to perform spinal anesthesia If PLR maneuver is contraindicated (intracranial hypertension) or possibly unreliable ( venous compression stocking, intraabdominal hypertension) Difficulties in IVC visualization due to increased subcutaneous fat tissue or gastric gas interferin

A total of 68 consecutive elderly patients, aged >65 years scheduled for elective infra-umbilical surgical operations under spinal anesthesia will be included in the study.