Abdominal Surgery, Genital Prolapse, Hysterectomy, Obesity
Conditions
Keywords
Fluid Management, surgery, Obesity
Brief summary
The investigators propose to determine esophageal Doppler goal-directed fluid requirements in lean, overweight, obese, and morbidly obese patients with the goal of developing a body mass index (BMI)-specific fluid replacement strategy. Specifically, th investigators will test the hypothesis that perioperative fluid requirements on a per-kg basis varies as a function of BMI. Individuals scheduled for elective, open abdominal surgeries, vaginal hysterectomies or genital prolapse repair will be eligible to participate
Detailed description
Recent evidence suggests that goal-directed fluid management using stroke volume (blood ejected by the heart) is the most physiologic approach for fluid replacement. We propose to develop a body mass index (BMI)-specific fluid replacement formula based on stroke volume guidance. Arterial pulse pressure variation (dPP) induced by mechanical ventilation is a proposed predictor of fluid responsiveness as well. We will therefore also investigate if stroke volume (measured by esophageal Doppler monitoring) and pulse pressure variation comparably predict fluid responsiveness by simultaneously measuring both parameters. Adequate tissue oxygenation is essential to maintain normal physiologic functions. Fat tissue oxygenation is critically low in the obese surgical patient. It is likely that poor fat tissue oxygenation results in part from inadequate fluid replacement. We propose to determine if fat tissue oxygenation is comparable from lean to morbidly obese patients when fluid replacement is optimized. Individuals scheduled for elective, open abdominal surgeries, vaginal hysterectomies or genital prolapse repair will be assigned to six groups according to BMI, from lean to morbidly obese categories. The primary aim will be to develop a statistical equation for predicting fluid requirements as a function of BMI. A maximum of 100 patients will be able to detect an R-squared of 10% or more with 90% power at the 0.05 significance level, and will enable adequate estimation of the relationship of interest.
Interventions
PROCEDUREEsophageal probe
Near-infrared spectroscopy (NIRS) sensor, polarographic-type tissue oxygen sensor (Licox®, esophageal probe
Sponsors
The Cleveland Clinic
Study design
Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 85 Years
Healthy volunteers
No
Inclusion criteria
1. Women, aged \> 18 years old 2. Scheduled for elective, open abdominal or vaginal hysterectomies. Patients will be recruited in the following body mass index categories: 1. 18.5-24.9 BMI \[kg/m2\] 2. 25.0-29.9 BMI \[kg/m2\] 3. 30.0-34.9 BMI \[kg/m2\] 4. 35.0-39.9 BMI \[kg/m2\] 5. 40.0-44.9 BMI \[kg/m2\] 6. \> 45 BMI \[kg/m2\]
Exclusion criteria
1. Hysterectomies due to gynecologic cancer diagnosis 2. Signs and/or symptoms of decompensate heart failure 3. End-stage renal disease 4. History of susceptibility to malignant hyperthermia or porphyria 5. Esophageal disease (excepting gastro-esophageal reflux without any other esophageal alteration)
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| To develop a statistical equation based on the BMI (Body Mass Index) that predicts fluid requirements in individuals scheduled for elective, open abdominal surgeries, vaginal hysterectomies or genital prolapse repair . | July, 2009 |
Secondary
| Measure | Time frame |
|---|---|
| To identify whether tissue oxygenation is similar in lean, overweight, obese and morbidly obese patients when perioperative fluid management is optimized. | July, 2008 |
Countries
United States
Outcome results
None listed