Free Flap Failure Research Articles

Risk Factors Leading to Free Flap Failure

The objective of this study was to identify risk factors for free flap failure among various anatomically based free flap subgroups. The 2005 to 2012 American College of Surgeons National Surgical Quality Improvement Program database was queried for patients undergoing microvascular free tissue transfer based on current procedural terminology codes. Univariate analysis was performed to identify any association between flap failure and the following factors: age, gender, race, body mass index (BMI), diabetes, smoking, alcohol use, hypertension, intraoperative transfusion, functional health status, American Society of Anesthesiologists class, operative time, and flap location. Factors yielding a significance of P < 0.20 were included in multivariate logistic regression models in order to identify independent risk factor significance for flap failure. Furthermore, patients were stratified based on recipient site (breast, head and neck, trunk, or extremity), and analysis was repeated in order to identify risk factors specific to each location. A total of 1921 of 2103 patients who underwent microvascular free flap reconstruction met inclusion criteria. Multivariate logistic regression identified BMI (adjusted odds ratio [AOR] = 1.07, P = 0.004) and male gender (AOR = 2.16, P = 0.033) as independent risk factors for flap failure. Among the "breast flaps" subgroup, BMI (AOR = 1.075, P = 0.012) and smoking (AOR = 3.35, P = 0.02) were independent variables associated with flap failure. In "head and neck flaps," operative time (AOR = 1.003, P = 0.018) was an independent risk factor for flap failure. No independent risk factors were identified for the "extremity flaps" or "trunk flaps" subtypes. BMI, smoking, and operative time were identified as independent risk factors for free flap failure among all flaps or within flap subsets.

Improvised perioperative techniques to meet the challenges of microvascular free flap surgery

Deformities of the head and neck region after radical oncosurgery can have devastating effects on the appearance of the patient with significant impact on patients quality of life. Reconstruction of such defects continues to be an extremely demanding challenge for plastic surgeons who aim to restore form and function with minimal surgical morbidity. The purpose of this communications is to highlight the various interventions and the protocols that are adopted to decrease the free flap failure rate.

The Efficacy of the Cook–Swartz Implantable Doppler in the Detection of Free-Flap Compromise: A Systematic Review and Meta-Analysis

Background Reducing free-flap failure rates is a key goal of any microsurgical unit. The Cook–Swartz implantable Doppler (CSD) can be used to monitor flap vascularity. We conducted a systematic review and meta-analysis to compare the efficacy of the CSD with clinical monitoring to prevent flap failure. Methods A comprehensive literature search was performed using MEDLINE, EMBASE, PsycINFO, EBSCO, the Cochrane Library, CINAHL, SCOPUS, SciELO, NHS evidence, and online clinical trial registers from 1966 until December 31, 2015. Studies comparing flap failure rates in the CSD and clinically monitored groups were considered. Screening and data extraction was performed by two independent researchers. Results Overall, eight articles met the inclusion criteria, involving 3,756 patients and 3,801 flaps. The average failure rate in the clinical group was 3.5% and in the Doppler group was 2.0%. A fixed effects meta-analysis was performed and found a reduced failure rate with the use of the CSD (odds ratio= 0.37 [0.21–0.64], p = 0.0005). Conclusion Deployment of the CSD can lower flap failure rates and has the potential to be a useful adjunct to clinical monitoring of free flaps. Further research is needed to confirm its benefits and refine its indications to optimize cost-effectiveness.

Influence of postoperative vasoactive agent administration on free flap outcomes

The use of vasoactive agents (VAs) in free flap reconstruction remains controversial due to the potential risk of free flap failure. Most of the existing literature has focussed on intraoperatively administered VAs in free flap procedures. However, hypotension frequently requires VA support, both intraoperatively and in the first postoperative days. The objective of this study was to analyse the influence of postoperatively administered VAs on thromboembolic complications. A retrospective study was performed including all patients undergoing free flap reconstruction between February 2010 and June 2012. Logistic regression analysis identified predictors for postoperative VA administration and whether its use was a prognostic risk factor for the outcome parameters of revision surgery or free flap loss due to vascular compromise of the venous or arterial anastomosis. A total of 209 free flap procedures were performed, with an overall survival rate of 94.3 %. In 19.7 % of the free flap procedures performed, postoperative VA administration was noted. Predictors for postoperative VA administration were intraoperative VAs, age ≥50, ASA ≥3, hypertension and peripheral vascular disease. Postoperative VA administration was found to be a significant risk factor for the outcome parameter of revision surgery, particularly in the perforator free flaps used for lower extremity reconstruction. However, there was no significant correlation between the postoperative use of VAs and free flap loss. We have demonstrated an association between postoperative VA administration and an increased revision rate in free flaps. Appropriate flap selection, close free flap monitoring and optimally adjusted anticoagulation therapy are recommended in patients receiving VA support during the early postoperative free flap period. Level of Evidence: Level III, risk/prognostic study.

Primary radical ablative surgery and fibula free-flap reconstruction for T4 oral cavity squamous cell carcinoma with mandibular invasion: oncologic and functional results and their predictive factors.

The aims of this study were to evaluate clinical outcomes and to determine their predictive factors in patients with oral cavity squamous cell carcinoma (OCSCC) invading the mandibular bone (T4) who underwent primary radical surgery and fibula free-flap reconstruction. Between 2001 and 2013, all patients who underwent primary surgery and mandibular fibula free-flap reconstruction for OCSCC were enrolled in this retrospective study. Predictive factors of oncologic and functional outcomes were assessed in univariate and multivariate analysis. 77 patients (55 men and 22 women, mean age 62±10.6years) were enrolled in this study. Free-flap failure and local and general complication rates were 9, 31, and 22%, respectively. In multivariate analysis, ASA score (p=0.002), pathologic N-stage (p=0.01), and close surgical margins (p=0.03) were independent predictors of overall survival. Six months after therapy, oral diet, speech intelligibility, and mouth opening functions were normal or slightly impaired in, respectively, 79, 88, and 83% of patients. 6.5% of patients remaining dependent on enteral nutrition 6months after therapy. With acceptable postoperative outcomes and satisfactory oncologic and functional results, segmental mandibulectomy with fibula free-flap reconstruction should be considered the gold standard primary treatment for patients with OCSCC invading mandible bone. Oncologic outcomes are dependent on three main factors: ASA score, pathologic N-stage, and surgical margin status.

Buried free flaps in head and neck reconstruction: higher risk of free flap failure?

Thrombosis of the pedicle is central to free flap failure, and early revision of a compromised flap is the key to successfully salvage a flap. Therefore, the majority of free flaps in reconstructive head and neck surgery are used with the ability to visually examine the flap. Sometimes, due to intra-operative circumstances, it is necessary to use a flap that cannot be monitored externally. These flaps are called buried flaps and have the reputation of being put at risk. The current literature provides only limited data to support or disprove this position. A single institution retrospective review of patient charts between 2007 and 2015 was performed. Flap monitoring was carried out with hand-held Doppler of the pedicle hourly for the first 72h in all cases. Additional duplex ultrasound was performed in the majority of buried flaps. A total of 437 flaps were included into the study. 37 flaps (7.8%) were identified to fulfill the criteria of a buried free flap. In total, four patients had complications, three of which required operative reexploration. All interventions were successful, resulting in no flap loss in our series. An accurate operation technique combined with meticulous monitoring protocols supported by duplex ultrasound can result in satisfactory outcome of buried flaps. No enhanced risk of flap loss of buried flaps was found in our cohort.

Critical time for neovascularization/angiogenesis to allow free flap survival after delayed postoperative anastomotic compromise without surgical intervention: A review of the literature.

The aim of this study is to determine the minimal postoperative time required that may allow free flap survival after occlusion or ligation of the microsurgical anastomosis without surgical intervention. All reports describing free flap survival and failure after delayed postoperative vascular compromise (after postoperative day 3); including thrombosis and ligation, without revision of the microsurgical anastomoses were reviewed. The type of flap, recipient site, vessel of occlusion, postoperative compromise day, and nonsurgical treatment were analyzed. 22 reports (32 flaps) detailed 16 arterial, 6 venous, and 10 simultaneously arterial and venous (vascular pedicle) compromise in 16 head and neck, 10 lower extremity, 4 breast, and 2 upper extremity free tissue transfers. 12 flaps survived without any intervention, 6 survived with conservative therapy (anticoagulation or leeches), and 14 survived despite pedicle ligation. The range of critical day of occlusion did not differ significantly among vessel types. 75% of arterial compromise occurred between 6 and 15 days. 75% of vascular pedicle compromise occurred between 8.5 and 18 days. When compared to jejunal flaps, skin flaps survived after earlier postoperative occlusion (10.2 vs. 20.8 days; P = 0.01). This analysis suggests that free flaps compromised by vascular thrombosis or pedicle ligation may survive with only conservative therapy when the event occurs after a minimal critical time period. Flap survival is more probable when arterial occlusion or pedicle ligation occurs after postoperative day 12, but this minimal critical period may be as low as 6 days for arterial occlusion. © 2016 Wiley Periodicals, Inc. Microsurgery 36:604-612, 2016.

Outcome of heavily pretreated recurrent oral squamous cell carcinoma after salvage resection: A monocentric retrospective analysis.

The goals of the present study were to analyze survival data of patients who received salvage surgery due to recurrent oral squamous cell carcinoma (OSCC) of the oral cavity with curative intent, and to investigate the feasibility of microvascular flap reconstruction in a heavily pretreated patient cohort. A total of 32 patients who received salvage surgery due to recurrent OSCC were included. The cohort was analyzed in regard to relevant clinical and pathological features. Survival was estimated by using Kaplan-Meier analysis and verified in a multivariate Cox regression model. All patients recovered well from surgery. The most common severe complication was free flap failure in 7 patients (24.1%). R0-resection was achieved in 16 patients (50%). Univariate Kaplan-Meier analysis showed that the estimated overall survival and disease-free survival of all patients after 24 months were 37.8% and 30.9%, respectively. Multivariate testing identified R1-resection was the only independent predictor of treatment failure. Salvage surgery is the only potential curative treatment option in recurrent OSCC. Microvascular reconstruction is feasible in heavily pretreated patients, but it is associated with a higher free flap failure rate. Recurrent OSCC in heavily pretreated patients shows different biological behavior. Further prospective clinical and molecular studies are needed to develop a better molecular understanding of recurrent OSCC and the best and safest individual therapeutic strategy.

Supraclavicular artery island flap (SCAIF): a rising opportunity for head and neck reconstruction.

Over the last 20years, free flaps have represented the gold standard for moderate to large head and neck reconstruction. However, regional flaps continue to evolve and still play an important role in a reconstructive surgeon's armamentarium, especially for the more delicate patients who would certainly benefit from simpler surgical procedures. The supraclavicular artery island flap (SCAIF) is a pedicled flap that has recently gained great popularity for reconstruction of most head and neck sites, because of its unusual versatility and wide arc of rotation. SCAIF is a fasciocutaneous flap that is very reliable and both easy and quick to harvest. It is pedicled on the supraclavicular artery, which is a branch of the transverse cervical artery. Between October 2012 and July 2015, at Ospedale San Raffaele (Milan, Italy) and Policlinico San Matteo (Pavia, Italy), we used the SCAIF procedure on 14 patients with cervical and facial skin, oral cavity, oropharyngeal, and hypopharyngeal defects after oncologic surgery or as revision surgery after free-flap failure. The presence of the supraclavicular artery was demonstrated preoperatively by computed tomography angiography. Harvesting time never exceeded 50min. Functional outcomes were excellent, and the donor site was always closed. We reported only one case of tip desquamation, which was treated conservatively, and two cases of partial flap necrosis, which required revision surgery. In our opinion, SCAIF should be considered to be a valid alternative to free-flap reconstruction, especially for facial and cervical skin, floor-of-mouth, and hypopharyngeal defects; oropharyngeal defects may be harder to reconstruct.

Predictors of free flap loss in the head and neck region: A four-year retrospective study with 451 microvascular transplants at a single centre.

Microvascular free flaps have become an essential part of reconstructive surgery following head and neck tumour ablation. The authors' aim was to investigate the influence of cardiovascular risk factors, preoperative irradiation, previous operations and metabolically active medication on free flap loss in order to predict patients at risk and to improve their therapy. All patients who underwent reconstructive surgery with microvascular free flaps in the head and neck region between 2009 and 2013 were retrospectively analysed. Uni- and multivariate logistic regressions were performed to determine the association between possible predictor variables for free flap loss. We included 451 patients in our analysis. The overall free flap failure rate was 4.0%. Multivariate regression analysis revealed significantly increased risks of free flap failure depending on prior attempts at microvascular transplants (p<0.001, OR=14.21) and length of hospitalisation (p=0.007, OR=1.05). With consistently low rates of flap failure, microvascular reconstruction of defects in the head and neck region has proven to be highly reliable, even in patients with comorbidities. The expertise of the operating team seems to remain the main factor affecting flap success. The only discerned independent predictor was previously failed attempts at microvascular reconstruction.

Use of systemic low-dose unfractionated heparin in microvascular head and neck reconstruction: Influence in free-flap outcomes

Background: Intravenous heparin administration is used to prevent thrombosis in free-flap transfer. However, it is unknown whether the use of heparin affects free-flap survival. The purpose of this study is to investigate the effect of heparin in free flap transfer. Methods: Two hundred and six patients who received ablative surgery for head and neck cancer were classified into three groups. Group A received ablative surgery, neck dissection, and free-flap reconstruction, and postoperatively they were administered continuous intravenous unfractionated heparin (5000–10 000 units/day) until postoperative day 7 (POD7); group B received the same procedures as group A but without heparin; group C received only ablative surgery and neck dissection without heparin. As indicators of coagulation time, the prothrombin time-international normalised ratio (PT-INR) and the activated partial thromboplastin time (APTT) were measured, before surgery and on POD1, 3, and 7. Flap failure, bleeding, haematoma formation, re-exploration, and thromboembolic events were recorded. Results: The PT-INR and APTT were 1.3–1.5-times longer in group A (p < 0.01), and 1.3-times longer (p < 0.01) in group B. The PT-INR and APTT were higher in groups A and B than C (p < 0.01). The free-flap success rate was not affected. Only the incidence of haematoma was increased in group A (p = 0.04). Conclusion: Heparin increased the haematoma formation, but did not change the incidence of free-flap failure. Thus, the intravenous low-dose heparin use does not affect microvascular flap survival.

Factors associated with failure of free gracilis flap in reconstruction of acute traumatic leg defects

Background: Possible factors associated with failure of free gracilis flaps were studied. Materials and methods: All gracilis free flaps used to reconstruct acute traumatic leg defects in a 5 year period were collected. This included open fractures of the tibia and/or fibula in which a gracilis free flap was used for reconstruction. Pre-op factors included age, ethnicity, gender, presence of diabetes, ischaemic heart disease, peripheral vascular disease, or coagulation disorders; days from trauma to flap surgery, Gustilo class, presence of a concurrent ipsilateral femur fracture, and use of CT angiogram to determine adequacy of blood supply. Intra-op factors included type of arterial anastomosis (end to side or end to end), presence of arterial transection, initial arterial anastomotic failure, initial venous anastomotic failure, use of systemic vasoconstrictors by anaesthetists for correction of hypotension, and use of modulators of the coagulation mechanism (dextran/heparin). Post-op factors included post-op day when flap was removed and use of modulators of the coagulation mechanism. Results: Patients with a concurrent ipsilateral femur fracture had a 9.67 (95% CI of OR = 1.32–70.96) times increased risk of flap failure compared to patients without an associated femur fracture. Conclusion: The finding of increased risk of free gracilis flap failure for coverage of leg defects in patients with ipsilateral femur fractures has implications on flap selection and pre-operative counselling. In such a situation, a non-microvascular option could be safer if it is available as an alternative.

Risk Factors for Free Flap Failure in 2,846 Patients With Head and Neck Cancer: A National Database Study in Japan

The risk factors for an unfavorable outcome after microvascular free flap reconstruction in head and neck cancer are not fully understood. We sought to identify factors affecting the occurrence of free flap failure. This was a retrospective cohort study using data from the national inpatient database in Japan between 2010 and 2012. We identified patients diagnosed with head and neck cancer who underwent tumor resection and consecutive free flap reconstruction. Cox proportional hazards regression was used to assess risk factors for free flap failure. The threshold for significance was P<.05. Missing data were imputed by using multiple imputation. We identified 2,846 eligible patients. The overall proportion of free flap failure was 3.3%. Free flap failure was associated with diabetes mellitus (hazard ratio [HR], 1.80; 95% confidence interval [95%CI], 1.18 to 2.76; P= .007), peripheral vascular disease (HR, 4.49; 95% CI, 1.61 to 12.52; P=.004), renal failure (HR, 3.67; 95% CI, 1.45 to 9.33; P= .006), preoperative radiotherapy (HR, 2.14; 95% CI, 1.11 to 4.13; P= .022), and duration of anesthesia greater than 18hours (compared with <12hours; HR, 2.72; 95% CI, 1.19 to 6.22; P= .018). Diabetes mellitus, peripheral vascular disease, renal failure, preoperative radiotherapy, and a longer duration of anesthesia were significant predictors of the occurrence of free flap failure.

Can E-Cigarettes Cause Free Flap Failure? A Case of Arterial Vasospasm Induced by Electronic Cigarettes Following Microsurgical Breast Reconstruction.

Sir: The vasoconstrictive effects of cigarettes is well documented and routinely discussed with patients seeking microsurgical breast reconstruction. It is generally accepted that patients stop smoking 2–4 weeks before the planned reconstruction to avoid vasoconstriction and to prevent issues with wound healing. Although studies have documented the consequences of cigarette smoking on flap failure and wound healing, no prior study has documented the potential consequence of free flap failure after the use of electronic cigarettes (e-cigarette).1 A 48-year-old woman with right intraductal carcinoma was presented in May 2015 for delayed autologous breast reconstruction. She is a former cigarette smoker who confirmed that she had stopped smoking before scheduling surgery. The patient underwent a bilateral muscle-sparing free transverse rectus abdominis musculocutaneous flap reconstruction without any intraoperative complications. The following morning, the Vioptix Tissue Oximeter (Fremont, Ca) reading on the left breast dropped to 35% with deteriorating clinical examination. Bedside evaluation 20 minutes later revealed a clinically healthy appearing flap with a 77% Vioptix signal (Fig. 1). Transient vasospasm was suspected. On postoperative day 2, the Vioptix reading on the left breast dropped to 3% with progressive flap deterioration. The decision was made to return to the operating room for an exploration. During transport to the operating room, the Vioptix reading returned to baseline; however, the decision to explore the anastomosis was maintained. Exploration revealed widely patient arterial and venous anastomoses without any kinks or twists of the pedicle. Nifedipine (10 mg per os daily) was started for presumed vasospasm. The patient then had an uneventful hospital course and was discharged home on postoperative day 4. It was later revealed to the plastic surgery team by the patient’s mother that the patient had been smoking e-cigarettes until the day of surgery.Fig. 1: Photograph of the patient and corresponding Vioptix readings (left flap is top reading, right flap is bottom reading) when initially called to see patient by nursing staff after a drop in the Vioptix reading to 35% on the left side. Upon examining the patient, her left flap appeared clinically healthy and the Vioptix reading rebounded to 77% spontaneously.E-cigarettes are battery-powered, vaporized nicotine delivery devices introduced into the U.S. in 2007 as a safe alternative to traditional tobacco-based cigarette smoking.2 The use of e-cigarettes has increased in popularity to more than 6% of the population in the U.S. with nearly one third of current smokers reporting to have ever used e-cigarettes.3 E-cigarettes are unregulated by the U.S. Food and Drug Administration and can be bought over the counter or online with no limit on the nicotine content. The vascular consequences of smoking traditional cigarettes/cigars are widely published and routinely counseled to patients; however, few providers discuss the use of e-cigarettes. Although e-cigarettes are free from many of the carbon monoxide, carcinogens, and tobacco present in traditional cigarettes/cigars, they contain variable amounts of nicotine that can cause peripheral vasoconstriction and inhibition of endothelial-dependent vasodilation, which can have devastating effects on free flaps.4 There are few publications about the consequences of e-cigarettes in the plastic surgery literature.5 This case example will help surgeons to advise patients on the risks of all tobacco products including e-cigarettes during the preoperative workup. DISCLOSURES M.Y.N. is a consultant for LifeCell. The other authors have no financial interest to declare in relation to the content of this article. The Article Processing Charge was paid for by Dr. Nahabedian. PATIENT CONSENT Patient provided consent for the use of her images and there are no patient identifiers in the images used.

Surgical exploration of 71 free flaps in crisis following head and neck reconstruction

The medical records of patients who had undergone a free flap reconstruction after radical resection of oral cancer between January 2009 and December 2013 at the study hospital in China were reviewed retrospectively. Of the 1550 patients who underwent free flap reconstructions, 71 were explored for suspected flap compromise caused by postoperative thrombosis. Patient demographic data, clinicopathological data of the tumour, details of the free flaps, and operative findings were assessed, and the medical records were analyzed to identify the reasons for intervention and the outcomes. Of the 71 flaps in crisis, 47 (66.2%) were salvaged. Free flap failure was 6.2-times more likely to develop in patients undergoing surgical exploration after 72h (95% confidence interval 2.090–18.197, P=0.001). Of the 19 flaps identified as subject to delayed exploration, 14 failed and three had partial necrosis. Free flap failure was 3.4-times more likely to develop in patients with perforator flaps (95% confidence interval 1.222–9.719, P=0.019). The early detection of free flap failure is critical to flap salvage. The salvage success rate decreases significantly at >72h after the initial operation. It appears to be more difficult to salvage a perforator flap.

The efficacy of the Cook-Swartz implantable doppler in the detection of free flap compromise: A systematic review and meta-analysis

Background Reducing free-flap failure rates is a key goal of any microsurgical unit. The Cook–Swartz implantable Doppler (CSD) can be used to monitor flap vascularity. We conducted a systematic review and meta-analysis to compare the efficacy of the CSD with clinical monitoring to prevent flap failure. Methods A comprehensive literature search was performed using MEDLINE, EMBASE, PsycINFO, EBSCO, the Cochrane Library, CINAHL, SCOPUS, SciELO, NHS evidence, and online clinical trial registers from 1966 until December 31, 2015. Studies comparing flap failure rates in the CSD and clinically monitored groups were considered. Screening and data extraction was performed by two independent researchers. Results Overall, eight articles met the inclusion criteria, involving 3,756 patients and 3,801 flaps. The average failure rate in the clinical group was 3.5% and in the Doppler group was 2.0%. A fixed effects meta-analysis was performed and found a reduced failure rate with the use of the CSD (odds ratio= 0.37 [0.21–0.64], p = 0.0005). Conclusion Deployment of the CSD can lower flap failure rates and has the potential to be a useful adjunct to clinical monitoring of free flaps. Further research is needed to confirm its benefits and refine its indications to optimize cost-effectiveness.

The relative survival of composite free flaps in head and neck reconstruction

Various composite free flaps are available for reconstruction of bony head and neck defects. The aim of this study was to compare the relative success of four different bony free flaps. One hundred and seventy-three microvascular composite free flap reconstructions for bony defects of the head and neck region, performed over the period April 2008 to April 2015, were reviewed retrospectively. The type of free flap, indication for free flap reconstruction, age at harvesting of the free flap, use of pre- or postoperative radiotherapy, and free flap failure were examined. For the 173 reconstructions performed, 84 fibula free flaps, 43 iliac crest free flaps, 32 scapula free flaps, and 14 osteocutaneous radial forearm free flaps were harvested. The mean age at time of harvesting was 40.7 years for the iliac crest, 57.3 years for the fibula, 64.3 years for the scapula, and 73.9 years for the osteocutaneous radial forearm free flap. No complete free flap failure was documented, nor was there any failure of bony segments. Three fibula flap skin paddles did not survive. No returns to theatre for salvage were required. This study showed no difference in the survival rates of these four types of composite free flap.

The venae comitantes clipping test for the evaluation of the venous drainage of the radial forearm free flap

Risks of failure of the radial forearm free flap (FRFF) are mainly related to venous congestion. Two different venous drainage system have been described for the FRFF, but the choice of the best one is still controversial. The superficial systems have a larger diameter and a thicker wall veins which makes them easier to anastomose. The deep system provides most part of the venous outflow if the caliber of the venae comitantes (VCs) is adequate. We propose an intra-operative method to evaluate the FRFF venous drainage: the VCs clipping test. The test has been used in the choice of the vein to anastomose in 12 consecutive patients with oral cavity post oncological defects reconstructed with the FRFF. The cephalic vein was included in the flap; the VCs were individually clipped with small liga-clips and divided with the radial artery still patent. The flap was kept with arterial inflow and superficial venous outflow till the recipient site was ready. If there were no signs of venous stasis, the VCs were kept clipped and the cephalic vein anastomosis was made. If clinical signs of venous stasis were revealed, the largest of the VCs was anastomosed to a vein of adequate caliber in the neck. No signs of flap venous congestion were observed in the postoperative period. No flap necrosis occurred. In this small series of patients the venae comitantes clipping test showed to be an easy, reliable and reproducible method to assess intra-operatively which vein to anastomose. © 2015 Wiley Periodicals, Inc. Microsurgery 36:647-650, 2016.

Risk Factors Associated with Free Flap Failure – An Analysis of 2103 Patients

INTRODUCTION: The use of microvascular free tissue transfer has steadily increased over the years, due to the ability to reconstruct complex defects.1–4 Fortunately, failure rates have decreased over the past few years, with improvements in surgical technique combined with better pre- and post-operative assessments, including patient selection.5–7 The viability of free flaps depends upon various patient-based factors. The objective of this study was to further identify risk factors that are associated with increased incidence of flap failure, especially with regards to specific types of free flaps based on anatomic location. METHODS: The American College of Surgeons National Surgical Quality Improvement Program database (ACS-NSQIP) was queried for all patients who underwent microvascular free tissue transfer from 2005 through 2012. Patients were identified based upon the following CPT codes: 15756, 15757, 15758, and 19364. Univariate analysis was performed to identify the association between free flap failure and the following factors: age, gender, race, body mass index (BMI), diabetes, smoking, alcohol, hypertension, intraoperative transfusion, functional health status, American Society of Anesthesiologists classification, operative time, and flap location. Factors yielding a significance of p <0.20 were included in multivariate logistic regression models in order to identify independent risk factor significance for flap failure. Furthermore, cases were stratified based upon recipient site (Breast, Head and Neck, Trunk, or Extremity), and analysis was repeated in order to identify risk factors specific to each location. RESULTS: 1921 of 2103 patients who underwent microvascular free flap reconstruction met inclusion criteria (Table 1). Multivariate logistic regression identified BMI (AOR = 1.07, p=0.004) and male gender (AOR = 2.16, p=0.033) as independent risk factors for flap failure. Among the “Breast Flaps” subgroup, BMI (AOR=1.075, p=0.012) and smoking (AOR=3.35, p=0.02) were independent variables associated with flap failure. In “Head and Neck Flaps,” operative time (AOR = 1.003, p=0.018) was an independent risk factor for flap failure. No independent risk factors were identified for the “Extremity Flaps” or “Trunk Flaps” subtypes (Table 2).Table 1: Frequency of Microvascular Free Flaps Among Each Flap Category.Table 2: Multivariate Analysis Indicated Adjusted Odds Ratios for Flap Failure.CONCLUSION: BMI was identified as an independent risk factor for flap failure among all microvascular free flaps and within the “Breast Flaps” subcategory. Smoking additionally was identified as an independent risk factor within “Breast Flaps.” Finally, increased operative time was a risk factor for flap failure among “Head and Neck Flaps.”

Intraoperative Use of Vasopressors Is Safe in Head and Neck Free Tissue Transfer

The purpose of this study is to identify whether intraoperative use of vasoactive medications increases the risk of free flap failure or complications through a systematic review and meta-analysis. PubMed/MEDLINE, EMBASE, and Scopus databases were searched for studies published through January 2015. English publications that met the following criteria were included: (1) adult patients undergoing head and neck free flap reconstruction; (2) comparison of patients with and without intraoperative vasopressor administration; and (3) documentation of flap failure rate and/or flap complications. The primary outcome was the incidence of flap failure. The secondary outcome was the incidence of overall flap complications. Meta-analysis was performed to obtain pooled odds ratios (ORs) of the effect of intraoperative use of vasopressors on flap failure and complication rates. Four cohort studies met inclusion criteria. All studies were of high methodological quality with an average Methodological Index for Non-Randomized Studies score of 18.75 (range 16-23). A total of 933 patients undergoing head and neck free flap reconstruction were included. Meta-analysis demonstrated no statistically significant difference in the incidence of flap failure (2.9 vs. 3.6%; OR, 0.68; 95% confidence interval [CI], 0.23-1.99; p = 0.48) or incidence of flap complications (16.8 vs. 18.6%; OR, 0.92; 95% CI, 0.60-1.42; p = 0.71). Based on the current evidence, intraoperative use of vasopressors has no impact on the incidence of flap failure or flap complications.