The altered hemodynamics, and therefore the arterial hypotension is the most prevalent adverse effect after subarachnoid anesthesia. The objective of the study was to determine the exact role of local anesthetic selection underlying spinal anesthesia-induced hypotension in the elderly patient. We conducted a descriptive, interventional pilot study to assess the hemodynamic impact of subarachnoid anesthesia with isobaric levobupivacaine versus isobaric bupivacaine for hip fracture surgery.

1. Objective of the trial 1.1. Main objective: Compare the hemodynamic effects from invasive systolic diastolic and mean blood pressures (ISBP, IDBP and IMBP) mesured in mmHg, arterial partial pressure of oxygen (PaO2) and arterial partial pressure of carbon dioxide (PaCO2) measured in mmHg , arterial oxygen saturation (SatO2) measured in%, heart rate (HR / bpm) measured in beats per minute.

   Other variables of interest will be: cardiac index (CI) mesured in litres per minute per square metre (L/min/m2), peripheral vascular resistance (PVR) medured in dynes/seconds/cm-5, partial arterial pressure of oxygen (PaO2) and arterial partial pressure of carbon dioxide (PaCO2) measured in mmHg, pH (pH), arterial lactate (Lc) measured in mmol / L, arterial hemoglobin (Hb) measured in g/dl, partial oxygen saturation (SpO2%) measured in %.

   1.2. Secondary objectives: Assess potential adverse events during surgery and 48 hours of surgery. Adverse events include adverse cardiovascular and respiratory rate, events related to both surgical and anesthetic techniques and exitus.

2. End points 2.1. Primary end point(s): hemodynamic variables invasive systolic blood pressure (ISBP) measured in mmHg invasive diastolic blood pressure (ISBP), measured in mmHg invasive mean blood pressure (IMBP), measured in mmHg arterial partial pressure of oxygen (PaO2) arterial partial pressure of carbon dioxide (PaCO2), measured in mmHg arterial oxygen saturation (SatO2) measured in% heart rate (HR / bpm) measured in beats per minute cardiac index (CI) mesured in litres per minute per square metre (L/min/m2). peripheral vascular resistance (PVR) mesured in dynes/seconds/cm-5 partial arterial pressure of oxygen (PaO2) measured in mmHg arterial partial pressure of carbon dioxide (PaCO2) measured in mmHg pH (pH) arterial lactate (Lc) measured in mmol / L arterial hemoglobin (Hb) measured in g / dl partial oxygen saturation (SpO2%) measured in %.

2.1.1 Timepoint(s) of evaluation of this end point: entry into the operating room, after 30 minutes of anesthesia and at the end of anesthesia.

2.2. Secondary end point(s):

A. Intraoperative adverse events:

1. Cardiovascular and Respiratory: Venous air embolism (VAE), deep vein thrombosis (DVT), myocardial infarction (AMI), cerebrovascular accident (CVA), congestive heart failure (CHF), pneumonia (N), Exitus (Ex)
2. Other: Acute renal failure (ARF), vomiting (V)
3. Associated with the surgical technique: RBC transfusion (Th), plasma transfusion (TPL), nerve damage (ln), femur fracture (Fx f)
4. Associated with the anesthetic technique: paresthesia (pair), hematic puncture (ph), other.

B.Postoperative adverse events (at 48 hours)

1. Cardiovascular and Respiratory: Deep vein thrombosis (DVT), myocardial infarction (AMI), cerebrovascular accident (CVA), congestive heart failure (CHF), pneumonia (N), Exitus (Ex)
2. Other: Acute renal failure (ARF), UTI (Infu), vomiting (V).
3. Associated with the surgical technique: RBC transfusion (Th), plasma transfusion (TPL), neurologic deficit (defnq), surgical wound infection (Infhq).
4. Associated with the anesthetic technique: neurological deficit (defn), postdural puncture headache (PDPH), back pain (Lumb).

2.2.1. Timepoint(s) of evaluation of this end point: 48 hours of surgery

Inclusion Criteria:

• Men and Women over 65 years
• Who meet the requirements in the pre-anesthetic to be treated with spinal anesthesia with levobupivacaine or bupivacaine, both with fentanyl,
• Fitness: from I to IV, according to the American Society of Anesthesiologists (ASA),
• Weight> 40 kg,
• Height> 140 cm,
• Body mass index (BMI) <50 kg/m2,
• Pathology cardiovascular, respiratory, renal and endocrine-metabolic,
• Provide written informed consent

Exclusion Criteria:

• Patients with uncontrolled hypertension (non-invasive systolic blood pressure> 180 mmHg and / or non-invasive diastolic blood pressure > 110mmHg),
• HR> 120 bpm,
• SpO2 <90% on arrival in the operating room and the contraindication to perform neuraxial anesthesia (patient refusal, infection at the site of puncture or lancing different, neuromuscular degenerative disease, hypovolemia, coagulopathy or anticoagulant therapy, morbid obesity, and extreme increase in intracranial pressure).