Intraocular Pressure During Spine Surgery

Study Overview
=================
Brief Summary
-----------------
This study will compare the effect of two intravenous solutions on eye pressure during spine surgery in the following groups: Group A - Lactated Ringer's replacement for blood loss and placebo eye drops Group B - Lactated Ringer's replacement for blood loss and brimonidine eye drops Group C - Albumin replacement for blood loss and placebo eye drops Group D - Albumin replacement for blood loss and brimonidine eye drops

Detailed Description
-----------------
Patients will be administered either brimonidine eye drops, or placebo eye drops, preoperatively, on the day of surgery and during surgery. Eye pressure will be measured before surgery, every 30 minutes throughout your surgery and every hour for 4 hours following surgery. Subjects will be evaluated before surgery and on days 5, 8, 15 after surgery. During these evaluations, the subject will be asked questions about recovery and his/her eyes will be checked by an ophthalmologist and vision will be tested.

Official Title
-----------------
The Effect of Lactated Ringer's Solution Versus Albumin and the Alpha-2 Agonist Brimonidine Versus Placebo on Intraocular Pressure During Prone Spine Surgery

Conditions
-----------------
Intraocular Pressure

Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Spine surgery with instrumentation in prone position expected to last at least 5 hours; Anticipated blood loss ≥ 1L Age 18-80 years old; ASA physical status I-III. Exclusion Criteria: History of increased intraocular pressure or glaucoma; Diabetic retinopathy; Heart failure or serious left ventricular dysfunction; Abnormal preoperative fundus examination; Creatinine > 2 mg/dL; Patient refuses blood transfusion or albumin administration

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| A<br>Lactated Ringer's replacement for blood loss and placebo eye drops | |
| B<br>Lactated Ringer's replacement for blood loss and brimonidine eye drops | |
| C<br>Albumin replacement for blood loss and placebo eye drops; | |
| D<br>Albumin replacement for blood loss and brimonidine eye drops | |

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The primary outcome will be the maximum intraocular pressure at any time during surgery. |  | 15 days post surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Intraocular pressure as a function of surgical duration; Velocity of retrobulbar blood flow; Facial edema and or chemosis; Time to extubation; Duration of recovery Correlation between Dpp and FTc. |  | 15 days post surgery | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Spinal surgery, Prone spinal surgery