Perioperative Vasopressor Use in Free Flap Surgery: A Systematic Review and Meta-Analysis

Abstract

Background The use of vasopressors in free flap surgery has traditionally been avoided due to the presumed risk of pedicle vasospasm leading to flap failure. However, there is a lack of strong clinical evidence to suggest that their administration during microvascular surgery is absolutely contraindicated. The aim of this study is to clarify the impact of perioperative vasopressor use on free flap outcomes. Methods A systematic review was performed of all English-language articles that have compared free flap outcomes between patients who received vasopressors and those who did not. The outcome measures were total flap failure, pedicle thrombosis, and overall flap complications. Meta-analysis was performed using Mantel–Haenszel fixed-effects and DerSimonian and Laird random-effects models. Results From a total of 130 citations, 14 studies representing 8,653 cases were analyzed. Majority of these did not find any negative effects of vasopressor use irrespective of dose, timing of administration, and method of delivery. Meta-analysis demonstrated that vasopressors were associated with less total flap failure overall (odds ratio, [OR]: 0.71, p = 0.05) and less pedicle thrombosis in head and neck reconstruction specifically (OR: 0.58, p = 0.02). Flap complication rates were similar across all defect types (OR: 0.97, p = 0.81) but appeared to be increased in breast reconstruction (OR: 1.46, p = 0.01). Conclusion Perioperative vasopressor administration does not appear to be as detrimental to free flap survival as has been previously feared. Their role in optimizing hemodynamic stability may have a more beneficial effect on overall flap perfusion and in minimizing the complications of iatrogenic fluid overload.

The Use of Vasopressor Agents in Free Tissue Transfer for Head and Neck Reconstruction: Current Trends and Review of the Literature

“…This controversy likely stems from the conventional theory that vasoactive drugs may result in vasospasm, decreased flap perfusion, and subsequent flap failure in a denervated flap ( Godden et al, 2000 ; Harris et al, 2012 ; Goh et al, 2019 ). Of note, these postulations are primarily based on experimental animal models with conflicting results ( Table 2 ) ( Banic et al, 1997 ; Cordeiro et al, 1997 ; Massey and Surgery, 2007 ; Lecoq et al, 2008 ; Scholz et al, 2009 ; Eley et al, 2013 ).…”

“…Moreover, in the only animal study to specifically examine the effects of flap perfusion in a free flap model, Banic et al, demonstrated no adverse effects on pedicle blood flow or free flap microcirculation with the systemic use of phenylephrine ( Banic et al, 1997 ). Thus, the use of vasopressors intraoperatively may actually increase flap perfusion due to improved overall MAP without significant deleterious effects from sympathectomy ( Rizzoni et al, 2000 ; Goh et al, 2019 ).…”

“…β-1 agonists primarily enhance cardiac output due to positive inotropic and chronotropic effects, while β-2 agonists cause smooth muscle relaxation in the lungs ( Miller and Pardo, 2011 ). Perioperatively, a host of endogenous and synthetic adrenergic agonists are available for use, each with varying degrees of effect on adrenergic receptors and associated physiologic and side effects ( Tables 2 and 3 ) ( Manaker and Parsons ; Barrett et al, 2007 ; Miller and Pardo, 2011 ; Goh et al, 2019 ).…”

“…Moreover, in a recent meta-analysis, Goh et al observed no significant difference in total flap failure rate between vasopressor (71/3444) and non-vasopressor (25/349) groups who underwent head and neck reconstruction (2.1% vs 3.3%; OR = 0.91, p = 0.72) ( Goh et al, 2019 ). A separate meta-analysis by Swanson et al demonstrated similar findings and showed that intraoperative vasopressors had no effect on the incidence of flap failure (2.9% vs 3.6%; OR = 0.68, p = 0.48) or complication rates (16.8% vs 18.6%; OR = 0.92, p = 0.71) ( Swanson et al, 2016 ).…”

“…Thus, vasopressors have often been historically and anecdotally associated with potential postoperative complications with 70% of surveyed surgeons prohibiting their use during microvascular surgery in a previous study ( Motakef et al, 2015 ; Chang et al, 2017 ). More recently, however, studies have challenged this paradigm and demonstrated an increased prevalence of intraoperative vasopressor use in free flap reconstruction without a significant impact on MFTT outcomes ( Monroe et al, 2011 ; Harris et al, 2012 ; Chan et al, 2013 ; Swanson et al, 2016 ; Fang et al, 2018 ; Goh et al, 2019 ).…”