Intraoperative Volume Status, Postoperative Complications
Conditions
Brief summary
The purpose of this study is to evaluate the feasibility of a closed-loop (automated) fluid administration system to deliver fluids using feedback from standard operating room hemodynamic monitors. In standard anesthesia care the rate of IV fluid administration to the patient is determined by the anesthesiologist caring for the patient. In this study protocol, the rate of fluid administration will be determined instead by the closed-loop (automated) control system under the supervision of the anesthesiologist. The system will independently decide when to give fluid and at what rate; the supervising anesthesiologist will monitor the system to ensure appropriate volumes are being delivered and to intervene if necessary.
Detailed description
In our protocol we will test the hypothesis that closed-loop fluid administration can maintain higher cardiac stroke volume (shown to improve patient outcomes after surgery) than anesthesiologist management. We have shown this to be the case in multiple simulation studies and in-vivo animal studies, but not yet experimentally in a clinical setting. Investigators will recruit their patients from the surgical record that that require cardiac output monitoring undergoing surgery and require mechanical ventilation and consent to participate in the study will be included in the study. They will receive standard patient care in that in no way will their anesthetic or surgical procedure will be altered as part of the study, with the exception of fluid administration. Fluids are usually given to a patient based on the physician's discretion. As part of the study patients will receive fluid management via a closed loop (automated) system that will use an infusion pump (Q-Core) and a controller (a computer run index and algorithm developed by Sironis) to make frequent, regular and accurate adjustments to the amount of fluid the patient receives using feedback from standard operating room monitors at UCI). Data from this study will be retrospectively compared to subjects case matched to evaluate differences in cardiac output, total fluid given, and patient outcomes.
Interventions
DEVICEClosed Loop
Fluid management in the closed loop group will be performed via a closed loop (automated) system that will use an infusion pump (Q-Core) and a controller (a computer run index and algorithm developed by Sironis) to make frequent, regular and accurate adjustments to the amount of fluid the patient receives using feedback from standard operating room monitors.
Sponsors
University of California, Irvine
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Adult subjects (over the age of 18) * Subjects undergoing elective major, abdominal surgery * Subjects requiring general anesthesia and mechanical ventilation * Subjects requiring cardiac output monitoring and an arterial line
Exclusion criteria
* Subjects under 18 years of age * Subjects not undergoing surgery * Subjects not requiring general anesthesia or mechanical ventilation * Subjects not requiring cardiac output monitoring or an arterial line * Subjects who are pregnant * Subjects without the capacity to give informed consent
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Fluid Status During Surgery | Duration of Surgery, up to 8 hours | The primary outcome between groups is preload independence, defined as % case time where Stroke Volume Variation (SVV) is ≤12%. |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Closed Loop Study patients will receive a baseline crystalloid infusion of 3 cc/kg/hr and all additional fluid management will be performed via a closed loop (automated) system that will determine rate, amount, and timing of fluid administration.
Closed Loop: Fluid management in the closed loop group will be performed via a closed loop (automated) system that will use an infusion pump (Q-Core) and a controller (a computer run index and algorithm developed by Sironis) to make frequent, regular and accurate adjustments to the amount of fluid the patient receives using feedback from standard operating room monitors. | 35 |
| Total | 35 |
Withdrawals & dropouts
| Period | Reason | FG000 |
|---|---|---|
| Overall Study | Discovery of Metastatic disease | 4 |
| Overall Study | Team chose not to place an a line | 1 |
Baseline characteristics
| Characteristic | Closed Loop |
|---|---|
| Age, Categorical <=18 years | 0 Participants |
| Age, Categorical >=65 years | 12 Participants |
| Age, Categorical Between 18 and 65 years | 23 Participants |
| Age, Continuous | 61.6 years STANDARD_DEVIATION 12.8 |
| ASA Physical Status patient classification 2 | 1 participants |
| ASA Physical Status patient classification 3 | 28 participants |
| ASA Physical Status patient classification 4 | 6 participants |
| Region of Enrollment United States | 35 participants |
| Sex: Female, Male Female | 16 Participants |
| Sex: Female, Male Male | 19 Participants |
| Specific Surgical procedure Complex cholecystectomy | 3 participants |
| Specific Surgical procedure Distal pancreatectomy | 5 participants |
| Specific Surgical procedure Liver resection | 10 participants |
| Specific Surgical procedure Whipple | 9 participants |
| Specific Surgical procedure Whipple + additional | 8 participants |
| Stroke Volume Index | 44 ml per meter-squared STANDARD_DEVIATION 10 |
Adverse events
| Event type | EG000 affected / at risk |
|---|---|
| deaths Total, all-cause mortality | — / — |
| other Total, other adverse events | 0 / 35 |
| serious Total, serious adverse events | 0 / 35 |
Outcome results
Primary
Fluid Status During Surgery
The primary outcome between groups is preload independence, defined as % case time where Stroke Volume Variation (SVV) is ≤12%.
Time frame: Duration of Surgery, up to 8 hours
Population: Closed Loop Study population at Stroke Volume Variation (SVV) ≤12%
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Closed Loop | Fluid Status During Surgery | 95 percentage of case time | Standard Deviation 6 |