Free Flap, Head and Neck Cancer, Hypotension, Oral Cancer
Conditions
Keywords
noradrenaline, norepinephrine, epinephrine, adrenaline, dobutamine, dopexamine, inotrope, pressor, sympathomimetic, free flap, transplantation, free tissue transfer, microsurgery, survival
Brief summary
Following surgery to remove tumours of the head and neck, patients undergo reconstruction with free flaps - tissue that is taken from elsewhere in the body and given a new blood supply by attaching it to vessels in the neck. Following this type of surgery, patients often need medication to maintain their blood pressure in the intensive care unit. The effect of these drugs on the transplanted tissues is unknown. This study investigates the effects of four commonly used drugs on free flap perfusion.
Detailed description
The optimal sympathomimetic drug to support blood pressure without adverse vasoconstriction of free flap circulation remains unknown. This study examined the effects of four agents (epinephrine, norepinephrine, dobutamine and dopexamine) on free flaps following resection of head and neck cancer. Twenty five patients were recruited to the study. Each patient received an infusion of the four drugs in a random order with an intervening washout period between drugs, at four infusion rates. Continuous free flap skin blood flow monitoring was performed using laser Doppler velocimetry, with a second sensor on normal skin acting as a control. Global cardiovascular variables were monitored using the LiDCO Rapid pulse contour analysis system.
Interventions
DRUGEpinephrine
0.2mcg/kg/min maximum infusion; to increase mean arterial pressure by 30mmHg
DRUGNorepinephrine
Maximum infusion of 0.2mcg/kg/min, to increase mean arterial pressure by 30mmHg
DRUGDobutamine
Maximum infusion rate of 8mcg/kg/min to increase mean arterial pressure by 30mmHg
DRUGDopexamine
Maximum infusion rate of 5mcg/kg/min to increase mean arterial pressure by 30mmHg
Sponsors
Oxford University Hospitals NHS Trust
Study design
Allocation
RANDOMIZED
Intervention model
SINGLE_GROUP
Primary purpose
DIAGNOSTIC
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
17 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Patients undergoing free tissue transfer surgery at the John Radcliffe Hospital wih planned post-operative admission to the intensive care unit.
Exclusion criteria
* Pregnancy * Weight \>100kg * Contraindications to pressor infusions * Overnight ventilation not indicated
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Absolute change in transfer function (flap vascular resistance) after pressor infusion. | Post infusion (at 4 hours) |
Secondary
| Measure | Time frame |
|---|---|
| Relative change in transfer function after pressor infusion compared with normal tissue. | Post infusion (at 4 hours) |
| Change in flap flow after pressor infusion | Post infusion (at 4 hours) |
| Differences in frequency spectrum of skin blood flow between flaps and normal tissue before and after pressor infusion. | Post infusion (at 4 hours) |
Countries
United Kingdom
Outcome results
None listed