A Prospective Study Evaluating the Use of Intraoperative Stroke Volume Variation Via the FloTrac Device to Guide Fluid and Vasopressor Management in Head and Neck Free Flaps

Does the Intraoperative Use of the FloTrac Device to Guide Fluid and Vasopressor Management Affect Postoperative Morbidity in Patients Receiving a Head and Neck Microvascular Free Tissue Transfer

This study aims to investigate whether the intraoperative use of the FloTrac device to guide fluid and vasopressor management during head and neck free flap surgery improves postoperative outcome. Primary postoperative outcome is length of hospital stay. Secondary postoperative outcomes include days in ICU, days on ventilator, presence of postoperative pulmonary edema, need for postoperative vasopressors or transfusions, 30 day flap complication rate, inpatient postoperative cardiorespiratory complications/events, and overall 30 day flap failure rate.

Study Overview

• Status: Completed
• Conditions: Head and Neck Cancer; Patients Requiring a Free Flap Surgery
• Intervention / Treatment: Device: FloTrac

Detailed Description

Few animal models have shown that intravenous vasopressor administration (including use of pure alpha agonists such as phenylephrine) can decrease blood flow to free musculocutaneous flaps (1-3). This has led to a dogmatic belief that all vasopressors should be avoided intraoperatively during a microvascular free flap reconstruction regardless of patient hemodynamics, even though there is little published evidence that pressors negatively affect free flap outcome (4). As a result, these patients often receive generous amounts of fluids during their intraoperative course to combat periods of hypotension. However, patients receiving head and neck free tissue transfers tend to be older with serious comorbidities related to long term tobacco use such as significant cardiovascular and pulmonary disease. Thus, they often exhibit intraoperative hemodynamic lability with periods of hypotension that may not necessarily be related to hypovolemia. Consistently treating periods of hypotension with more intravenous fluids can lead to serious postoperative complications such as graft failure (4), pulmonary edema, and congestive heart failure. In fact, we have just completed a retrospective review of 248 patients over a 34 month period that received a head and neck free tissue transfer; we discovered that a 1ml/kg/hr increase in intraoperative fluid administration significantly increased 30 day flap complication rate while intraoperative administration of vasopressors did not affect 30 day flap complication or 30 day failure rate.

The FloTrac device is an approved and validated medical device that analyzes the arterial pressure waveform to calculate a stroke volume variation. This stroke volume variation can be used to better guide intraoperative patient therapy with regard to need for fluid vs. pressor management during periods of intraoperative hypotension (5). The use of the FloTrac device for goal directed therapy has been investigated in major abdominal surgery and found to decrease length of hospital stay and complication rate in this surgical population (5-6). Thus, it is possible that the intraoperative use of the FloTrac device can better guide anesthesia providers to provide the necessary therapy for intraoperative hypotension in patients undergoing head and neck freet tissue transfer, thus improving postoperative outcome.

• Study Type: Interventional
• Enrollment (Actual): 94
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • South Carolina
    • Charleston, South Carolina, United States, 29425
      • Medical University of South Carolina

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• adults requiring "free flap" tissue reassignment surgery for head and neck cancer at either MUSC or Vanderbilt Medical Center

Exclusion Criteria:

• Patients < 55kg or > 140 kg based on literature regarding accuracy of flotrac.
• Patients with sustained intraoperative dysrrhythmias based on literature regarding accuracy of flotrac (ie, atrial flutter, atrial fibrillation).
• Patients with diagnosed NYHA class III-IV failure or documented EF < 30%
• Patients with pulmonary disease preventing administration of goal tidal volumes without excessive inspiratory pressures.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Supportive Care
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
No Intervention: Usual Care; Arterial line (radial, femoral, dorsalis pedis, or brachial), central line for access when needed, intubation vs tracheostomy, general anesthesia. We currently use stroke-volume variability monitoring (FloTrac) in all patients using the arterial line placed for blood pressure monitoring.
Experimental: Treatment; The study will use a treatment algorithm for patients in the treatment group. This algorithm will aim to maintain a near-normal blood pressure and use goal directed therapy to achieve this. Currently the standard of care is to use IV fluid exclusively in these patients and anesthesia providers everywhere have been challenging that treatment plan. Our algorithm has an iterative approach assessing volume status, cardiac output and vascular tone in order, with interventions specified for each. Individual treatments have been proven safe and effective in this population, we believe this sequence may be the best current management system. By avoiding excessive fluid administration we expect to decrease ICU length of stay due to the comorbidities caused (pulmonary edema, bowl edema, glycocalyx damage).	Device: FloTrac

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
ICU Stay	The primary outcome is length of ICU stay.	Participants were assessed from entry into ICU until departure.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of Participants Requiring a Ventilator	The secondary outcome is decreasing patient morbidity by comparing the number of patients on the ventilator	The number of participants requiring a ventilator after surgery.

Collaborators and Investigators

• Sponsor: Medical University of South Carolina

Study record dates

Study Major Dates

• Study Start: December 1, 2012
• Primary Completion (Actual): October 1, 2014
• Study Completion (Actual): October 1, 2014

Study Registration Dates

• First Submitted: June 20, 2014
• First Submitted That Met QC Criteria: July 7, 2014
• First Posted (Estimate): July 10, 2014

Study Record Updates

• Last Update Posted (Actual): September 20, 2018
• Last Update Submitted That Met QC Criteria: August 21, 2018
• Last Verified: August 1, 2018

More Information

Terms related to this study

• Keywords: head and neck cancer; patients requiring a free flap surgery
• Additional Relevant MeSH Terms: Neoplasms; Neoplasms by Site; Head and Neck Neoplasms
• Other Study ID Numbers: ENT FloTrac