The Effect of High vs. Low Fluid Volume on Ocular Parameters in Prone Spine Surgery

Fudan University

Status: Completed

Conditions: Prone Position; Blood Volume; Intraocular Pressure

Treatments: Other: Ringer's Lactate solution; Procedure: Spine surgery under general Anesthesia in the prone position

Study type: Interventional

Funder types: Other

Identifiers

NCT03890510

FOCUS

Details and patient eligibility

About

The purpose of this trial is to compare the effect of different fluid volume infusion on ocular parameters in patients undergoing spine surgery in prone position.

Full description

In the prone position, the intraocular pressure and optic nerve sheath diameter increase progressively with time as compared with those in the supine position. Excessive fluid infusion may further increase intraocular pressure and optic nerve sheath diameter. Pulse pressure variation (PPV) is a dynamic index which can effectively assess fluid responsiveness during general anesthesia.Therefore,the investigators have designed a study to compare the effect of different fluid volume infusion guided by low and high PPV indices on intraocular pressure and optic nerve sheath of patients undergoing prone spine surgery with general anesthesia. One group of the patients will receive relatively loose fluid infusion (target value of PPV: 6%-9%),while the other group of the patients will receive limited fluid infusion (target value of PPV: 13%-16%).

Enrollment: 97 patients

Sex: All

Ages: 18 to 60 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Scheduled for elective spine surgery in prone position under general anesthesia
• American Society of Anesthesiologists (ASA) physical status I or II
• Have signed consent form

Exclusion criteria

• History of eye disease or eye surgery
• Pregnancy or breast feeding
• Known Allergy to latex or Ringer's lactate solution
• Hyperlactacidemia，uncontrolled hypertension, diabetes mellitus, arrhythmia, cardiovascular disease，chronic pulmonary disease, swelling of any body part, abnormal of liver or renal function, anemia, etc.
• Body mass index（BMI）>30
• Expected operation time >6 hours
• Estimated Intraoperative hemorrhage >1000ml
• Taking part in other clinical trials in the last 3 months or at present

Trial design

Primary purpose: Prevention

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Triple Blind

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97 participants in 2 patient groups

Low PPV Group

Active Comparator group

Description:

After anesthesia induction, patients will receive spine surgery under general anesthesia in the prone position. Ringer's lactate solution will be infused at 1ml/（kg·h ） as a basal speed. Ringer's lactate solution at a volume of 250ml will be used as a bolus dose. Repeat bolus doses will be given to maintain PPV at 6\~9% when necessary. Intraoptic pressure and optic sheath diameter will be measured at multiple time points.

Treatment:

Other: Ringer's Lactate solution

Procedure: Spine surgery under general Anesthesia in the prone position

High PPV Group

Active Comparator group

Description:

After anesthesia induction, patients will receive spine surgery under general anesthesia in the prone position. Ringer's lactate solution will be infused at 1ml/（kg·h ） as a basal speed. Ringer's lactate solution at a volume of 250ml will be used as a bolus dose. Repeat bolus doses will be given to maintain PPV at 13\~16% when necessary. Intraoptic pressure and optic sheath diameter will be measured at multiple time points.

Treatment:

Other: Ringer's Lactate solution

Procedure: Spine surgery under general Anesthesia in the prone position