Safety of Vasopressor Use in Head and Neck Microvascular Reconstruction

Abstract

Intraoperative vasopressor use may be more common than previously realized in free tissue transfer surgery. Intraoperative vasopressor use does not result in a significant absolute increase in the rate of flap deaths.

Evidence to Support Controversy in Microsurgery

“…Several large retrospective reviews and one prospective observational study in head and neck surgery suggest that intraoperative use of pressors, most commonly phenylephrine, does not predispose to flap failure (Level III Evidence). [138][139][140][141] This has also been confirmed in breast microsurgery (Level III Evidence). 142…”

Emerging Paradigms in Perioperative Management for Microsurgical Free Tissue Transfer

“…93 Interestingly, in several clinical studies, intraoperative vasopressor administration affected neither the incidence of flap loss nor the rate of reoperation. [29][30][31][32][33] Cumulative dosage and timing of vasopressor administration showed no correlation with adverse outcomes. 29,33 Dobutamine has been shown to significantly improve flap flow.…”

“…Preoperative hemoglobin values below 11 g/ dl are associated with an increased length of stay 3b Ideal anesthetic agent unclear; consider sevoflurane Sevoflurane may have protective effects on the endothelium in the context of ischemia-reperfusion injury [13][14][15][16] and may promote vascular healing 17 Sevoflurane superior to propofol with regard to its effects on the capillary filtration coefficient 18 2b Use supplemental epidural anesthesia for lower extremity free tissue transfer Epidural supplementation of general anesthesia correlated with improved flap survival and lower rate of microvascular complications compared with general anesthesia alone 19 1b Implement sympathetic blockade for microsurgery involving the digits Axillary brachial plexus blockade correlated with increased perfusion in replanted digits 20,21 Fluids 2b Maintain crystalloid administration between 3.5-and 6 ml/kg/hr in the 24-hr perioperative period Crystalloid administration >130 ml/kg/day (>5.4 ml/kg/hr) associated with increased major medical complications 22 Extremes of crystalloid infusion associated with increased complications 23 2b Crystalloid administration should not exceed 7 liters intraoperatively Administration of >7 liters of crystalloid during surgery associated with major medical complications and flap complications 24 2b Consider hemoglobin/hematocrit during patient selection Significantly increased risk for flap failure with hematocrit <30%, hemoglobin <10 g/dl 25 2b Restrict blood transfusions to patients with hemoglobin <7 g/dl or who are clinically symptomatic Intraoperative blood transfusion associated with length of surgery, intraoperative arterial thrombosis, major surgical/medical complications 26 Increased risk for cancer recurrence and increased mortality in patients with oral/oropharyngeal squamous cell carcinoma receiving 3 or more units of blood perioperatively 27 Vasodilators 4 Consider topical, low-dose lidocaine to treat persistent vasospasm Application of 4% topical lidocaine during and after surgery improved blood flow in patients with persistent vasospasm 28 Vasopressors 2b Use vasopressors when indicated for hypotension; they do not significantly increase flap failure or complication rates Vasopressor administration did not affect the rates of reoperation, complete flap loss, partial flap loss, or fat necrosis in microsurgical breast reconstruction 29 Vasopressor administration did not affect flap failure rate or complications in head and neck reconstruction 30,31 Vasopressor administration did not affect flap failure rate or complications in upper and lower extremity reconstruction 32 Cumulative dosage and timing of vasopressor administration are not correlated with adverse outcomes 29,33 1b Consider norepinephrine and dobutamine for hypotension following free tissue transfer In a comparison of norepinephrine, dobutamine, epinephrine, and dopexamine administered following free tissue transfer, free flap skin blood flow increased in a dose-dependent manner with norepinephrine and dobutamine, with maximal improvements occurring with norepinephrine; dopexamine and epinephrine decreased flap blood flow 34,35 Dobutamine significantly improved both mean and maximum blood flow through the arterial anastomosis in patients during head and neck reconstructive surgery 36 Altho...…”

“…[29][30][31]33,73 Animal studies have demonstrated an attenuated response to norepinephrine and phenylephrine following surgical sympathectomy. 91 Following vasopressor administration, cutaneous microcirculation actually increased in an amount proportional to the change in mean arterial pressure in postsympathectomy tissue, whereas flow in normal tissue was reduced.…”

Continuous high‐dose vasopressors in free anterolateral thigh flap transfer for pharyngeal reconstruction: A report of two cases

“…However, recently published articles have studied patients receiving intraoperative vasopressors during free flap reconstruction of the head and neck, as well as breast, and have found no significant increase in flap related complications. Two of these studies reported that these doses of vasopressors were given as intermittent boluses; the other three did not report on the duration or rate of the vasopressor administration.…”