Effects of Intraoperative, Goal-directed Crystalloid vs. Colloid Fluid Resuscitation on Free Flaps

Study Overview
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Brief Summary
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Maintaining satisfactory tissue perfusion is an essential of success during reconstructive free flap surgery following malign oral cavity tumours. Intra- and postoperative goal-directed fluid therapy is an appropriate tool for that. Continuous cardiac output monitoring based fluid loading (complemented with vasopressor and/or inotropes if necessary) might be superior to conventional, central venous and arterial pressure monitoring in terms of morbidity, complications, optimal fluid balance and days spent in hospital. However, there is no data describing the effects of goal-directed fluid therapy (crystalloid or colloid) on microcirculation of free flaps implanted in the oral cavity during the post-operative period. The aim of this study is to observe the effects of continuous macrohaemodynamic monitoring based, goal-directed fluid therapy on microcirculation of forearm flaps during the perioperative period.

Official Title
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Effects of Intraoperative, Goal-directed Crystalloid vs. Colloid Fluid Resuscitation on Microcirculation in Free Flap Reconstruction of Intraoral Tumours.

Conditions
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Optimal Tissue Perfusion

Intervention / Treatment
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* Other: Fluid management
* Drug: Norepinephrine
* Drug: Dobutamine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age over 18 Tumour location: intraoral Free flap type: radial forearm Signed informed concent form Exclusion Criteria: Vulnerable subject as defined in International Standards Organization 14155:2011 End stage oral cancer

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Crystalloid group<br> | Other: Fluid management<br>* Primary fluid admission: 1 mL/bodyweight kg/ hour crystalloid. If Pulse pressure variation is lower than 10%; 250 mL/15 min of colloid or crystalloid is administered depending on randomization.<br>Drug: Norepinephrine<br>* Norepinephrine is administered if Mean arterial pressure drops below 65 mmHg. Mean arterial pressure must be maintained above 65 mmHg. Norepinephrine is titrated accordingly.<br>Drug: Dobutamine<br>* Dobutamine is administered if Cardiac index drops below 2.5 L/min/m2. Cardiac index must be maintained above 2.5 L/min/m2. Dobutamine is titrated accordingly.<br>|
| Active Comparator: Colloid group<br> | Other: Fluid management<br>* Primary fluid admission: 1 mL/bodyweight kg/ hour crystalloid. If Pulse pressure variation is lower than 10%; 250 mL/15 min of colloid or crystalloid is administered depending on randomization.<br>Drug: Norepinephrine<br>* Norepinephrine is administered if Mean arterial pressure drops below 65 mmHg. Mean arterial pressure must be maintained above 65 mmHg. Norepinephrine is titrated accordingly.<br>Drug: Dobutamine<br>* Dobutamine is administered if Cardiac index drops below 2.5 L/min/m2. Cardiac index must be maintained above 2.5 L/min/m2. Dobutamine is titrated accordingly.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes of Pulse pressure variation during the operation and the post-operative 24 hours |  | 24 hours | 
| Assesment of free falp microcirculation by laser dopler flowmetry method. |  | 24 hours | 
| Total need of Norepinephrine and Dobutamine during surgery and the post-operative 24 hours. |  | 24 hours | 
| Changes of Cardiac Index during the operation and the post-operative 24 hours. |  | 24 hours | 
| Mean arterial pressure during the operation and the post-operative 24 hours. |  | 24 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Length of Intensive Care Unit stay |  | 24 hours | 
| Number of surgical or non-surgical complications. |  | 24 hours | 
| Length of Hospital stay |  | 10 days |