The fate of free flaps used to reconstruct defects in recurrent head and neck cancers

Flap loss in head and neck reconstruction: Is there a singular cause for failure?

Despite the high success rates reported in head and neck reconstruction, free flap failures continue to persist. Understanding the factors associated with flap loss and improving overall success are paramount. This study aimed to comprehensively assess the factors influencing flap revision and free tissue transfer survival in head and neck reconstruction. The study included 70 patients with defects in the lower two-thirds of the head and neck region and underwent reconstruction using free flaps. Patient age, gender, smoking status, comorbidities and data on the location and aetiology of the defect, the specific type of flap employed, the recipient artery and vein chosen, instances of revision and the overall success of the flap were collected. The investigation aimed to establish correlations between these variables as well as flap success and revision rates. No statistically significant differences were observed in arterial and venous anastomosis revision rates, or flap survival, in relation to variables such as age, gender, flap type, smoking status, comorbidities, recipient artery or vein and the number of vein anastomoses. The malignant tumour group exhibited a lower requirement for arterial revision and a higher flap survival rate compared to the benign tumour group. This study underscores the comparable safety profiles of perforator-based and conventional flaps in head and neck reconstruction. Furthermore, it reveals that patient characteristics are not contraindications for free tissue transfer. Additionally, the quantity of the veins and choice of recipient vessels are flexible and do not significantly impact flap success. The higher rates of flap success in patients with malignant aetiology requires further investigation.

Microvascular Flap Reconstruction for Head and Neck Cancers in Previously Operated and/or Radiated Neck: Is It Safe?

BACKGROUND

Microvascular reconstruction after oncologic resection with curative intent in recurrent or second primary cancer cases is challenging not only because of the complexity of the defect but also due to difficulty in finding suitable donor vessels in the neck that has already been subjected to surgery and subsequent adjuvant treatment. In our present study, we evaluated the success of free flaps, reexplorations, and factors associated with reexploration and with flap failures in previously operated and/or radiated neck.

METHODS

In this retrospective study, we analyzed patients who underwent microvascular reconstruction from January 2016 to December 2018 in patients with previous surgery and/or radiation, considered as "already treated neck" (ATN). These cases were reviewed to analyze variables that included age, sex, indication for surgery (recurrence, second primary, osteoradionecrosis, and secondary reconstruction), duration since previous surgery or radiation, free flap done, donor vessels used, the need to go to the contralateral neck or outside the neck, need for vein grafts, flap reexploration rate, flap survival rate, and hospital stay of the patients. We also tried to identify factors that predisposed for a reexploration after performing reconstruction with a free flap in ATN.

RESULTS

Of 1522 free flaps done, 371 patients were included in the study. Flap success rate was 90.8% in ATN, which was comparable to naive neck (94%; P = 0.108). The reexploration rate in ATN (16.2%) was significantly higher (P = 0.0003) than in naive neck (9.8%). The previous treatment (neck dissection) received [P = 0.001; odds ratio, 13.7 (1.87-101.6)] was the most significant predisposing factor, and patients undergoing osteocutaneous flaps were more prone to undergo reexplorations (P = 0.05). Side of anastomosis, vessel used for anastomosis, comorbidities, and time since previous treatment did not affect the reexploration rate significantly.

CONCLUSIONS

Microvascular reconstruction can be safely performed in ATN with good success rates, and it should not be a deterrent in whom free flap is required to achieve best functional outcome. However, it may be associated with increase in reexploration rates in the postoperative period. Patients having undergone a previous neck dissection are at more risk of undergoing this reexploration in comparison with radiotherapy (RT)/chemotherapy and radiotherapy (CTRT) alone.

Is Brachytherapy Feasible After Head and Neck Cancer Reconstructive Surgery? Preliminary Report

The purpose of the study was to evaluate the influence of interstitial postoperative brachytherapy for the vitality and quality of flaps used for reconstruction of tissue defects after head and neck cancer salvage resection. We aimed at presenting six consecutive patients with recurrent squamous cell carcinoma in head and neck region who underwent salvage surgery and tissue reconstruction with a regional or free flap followed by brachytherapy. Reconstruction was performed with a free radial forearm flap in 2 cases, with a free thigh flap in 2 cases, and with a myocutaneous lateral upper arm flap in the next 2 cases. In all patients, pulsed-dose-rate brachytherapy was used with a median value of 0.7 Gy (range 0.6–0.8 Gy) per pulse and a median total dose of 20 Gy (range 20–40 Gy). In the analyzed group, there were no serious wound and flap complications after brachytherapy. In one case, peripheral skin necrosis was noticed. No revision surgery was needed but only surgical debridement of the necrotic margins. All wounds healed within 14 days after surgery as well as donor sites which healed within 4 weeks. Based upon our data, pulsed-dose-rate brachytherapy seems to be a safe option that can be performed at the site of reconstruction in immediate postoperative period with minimal wound complications and with no impact on flap survival. Further clinical study based on larger patient series is needed to present statistically proven results.

Anaesthetic implications of free-flap microvascular surgery for head and neck malignancies – A relook

Head and neck free-flap microvascular surgery is a type of surgery where multiple anaesthetic factors play a very important role in the outcome of the surgery while the conduct of anaesthesia itself may be quite challenging for the anaesthesiologist. In microvascular reconstruction of head and neck malignancies, flaps are used to reconstruct a primary defect formed by wide local excision. A free flap is raised after removing the neurovascular pedicle from the donor site and transplanting it by microvascular anastomosis to the new location. This gives rise to a secondary defect which is then repaired by direct suture or skin graft. The anaesthesiologist’s role includes optimizing the physiological conditions for the survival of the flap while decreasing morbidity at the same time. Failure of the free flap is attributed to numerous causes. This is an attempt to highlight them along with discussion of the anaesthesia-related issues that are faced during this type of surgery. The various pre-, intra- and postoperative factors affecting flap survival and overall postoperative outcome in the patient are discussed here.

The Cost of the "July Effect" in Microsurgery

The existence of the "July effect," or the idea that the new academic year intrinsically has an increased complication rate is evaluated in microsurgical free tissue transfer procedures. The National Surgical Quality Improvement Program registry was queried for all free flap procedures performed between 2005 and 2016 (n = 3405). Cases were grouped as having occurred in the first academic quarter (Q1: July 1-September 30) or fourth quarter (Q4: April 1-June 30). Demographical data and complications were compared using univariate χ analysis, multivariate logistic regression was used to control for confounding variables, and inpatient stay and operating cost estimates were created. Of a total of 1722 cases, 905 were performed in the first academic quarter and 817 were performed in the fourth academic quarter. There was no significant difference between Q1 and Q4 in readmission rate (P = 0.378) or reoperation rate (P = 0.730). Patients in Q1 had significantly longer operative times (P = 0.001) and length of stay (P = 0.002) compared with those in Q4. In addition, cost of inpatient stay and operating costs associated with each free flap were significantly increased in Q1 compared with Q4 (P = 0.029; P = 0.001). The total cost per quarter for free flaps was also significantly more expensive in Q1 vs Q4, with the highest average difference in cost of $350,010.64 (P = 0.001). Having surgery early in the academic year does not put patients at any increased risk for major complications but is associated with increased operating time, length of stay, and total cost.

Reconstruction in head-and-neck cancers - analysis of the learning curve

BACKGROUND

Oral cancers are some of the most common cancers in India. Most patients present with locally advanced disease requiring extensive resection resulting in large defects. Reconstruction of these defects plays a major role in restoring form and function to these patients, as well as enabling the delivery of adjuvant therapy on time.

AIM OF THE STUDY

The aim of this study was to analyze the learning curve involved in microvascular surgery.

MATERIALS AND METHODS

A retrospective analysis of the case records of all patients of oral cancers, who underwent resection and reconstruction between January 2008 and December 2012 at our institute, was done. Demographic, clinical, and pathological data were collected and analyzed. Statistical analysis was done using the SPSS software.

RESULTS

The operative time and the postoperative ventilation (7.8 h and 3.7 days, respectively) were significantly higher than those for pedicled flaps (3.6 h and 1.4 days, respectively). Both these variables reached statistical significance with P < 0.05 and < 0.04. The hospital stay was also statistically significantly longer for patients who underwent free-flap reconstruction (17.9 days vs. 7.9 days; P < 0.05). The number of reexplorations were higher in the free-flap group (31), when compared to the pedicled flap group (9). However, partial flap loss was higher in the pedicled flap subset when compared to the free-flap group. The complications significantly dropped after the performance of 30-40 free flaps.

CONCLUSION

There is a steep learning curve in microvascular surgery, but the cosmetic and functional outcomes outweigh the complications.

Head and neck reconstruction with free flaps: a report on 213 cases

The aim of this retrospective study is to review the experience of our institution in performing microvascular head and neck reconstruction between 2000 and 2004. During this period, 213 free flaps, including 146 radial forearm free flaps, 60 fibular flaps and 7 scapular flaps, were performed. Free flap success rate and complications were reported. The pre-treatment factors influencing these results were subsequently analyzed. Functional and aesthetic outcomes were evaluated by the same clinician. There were 14 free flap failures, giving an overall free flap success rate of 93.4%. Salvage surgery for recurrent cancer was the only factor correlated with a higher risk of free flap failure (P = 0.0004). The local complication rate was 20.9%. High level of comorbidity (P = 0.009), salvage surgery for recurrent cancer (P = 0.03) and hypopharyngeal surgery (P = 0.002) were associated with a higher risk of local complications. An unrestricted oral diet and an intelligible speech were recovered by respectively 76 and 88% of the patients. Microvascular free flaps represent an essential and reliable technique for head neck reconstruction and allow satisfactory functional results.

Head and neck reconstruction with a second free flap following resection of a recurrent malignancy

A retrospective analysis of 12 patients with a head and neck tumor recurrence within a previous free flap treated with extirpation and a second free flap is reported. A 15-year experience at Mayo Clinic, Rochester, from 1988 to 2003 of 12 patients (5 men, 7 women) who underwent 25 free flaps is reviewed. The overall flap survival rate was 92%, with a 100% survival rate in the first free-tissue transfer and 85% survival rate in the second free-tissue transfer. There was 1 minor complication (8%) and there were 2 major complications (15%) among the second free flaps. Overall, 10 of 13 (77%) second free flaps were anastomosed to ipsilateral neck vessels. Moreover, in 5 of 13 cases (38%) the same artery and in 7 of 13 cases (54%) the same vein were used for both the first and second free flaps. Reconstruction of the head and neck with a second free flap in patients with a recurrent tumor is safe and effective. The original recipient vessels can often be used for the second reconstruction.

Success of Multiple, Sequential, Free Tissue Transfers to the Head and Neck

INTRODUCTION

Free tissue transfer has become the primary reconstructive modality for significant ablative defects in the head and neck. The overall success rate is high, approaching 95% in most centers. The success rate of multiple sequential free flaps has been thought to be lower, based on the absence of optimal vessel availability and the presence of significant scar tissue in the previously operated patient. We evaluated a series of patients who underwent multiple free flaps at different time points to determine the overall success rate and to identify pitfalls encountered in this population.

METHODS

Retrospective review, tertiary care medical center.

RESULTS

From 1995 to 2002, 377 free flaps were performed by our reconstructive service. Of this group, 36 underwent multiple free flaps at different time points. Thirty-two had two flaps, and four had three flaps. Reasons for performing sequential free flap procedures were as follows: recurrent disease/new primary (18), need for further augmentation (10), failed previous flap (6), delayed mandibular reconstruction after plate fracture (2), mandibular osteoradionecrosis (3), and delayed pharyngoesophageal stenosis (1). The overall failure rate on the second and third flap was 2 of 32 and 0 of 4, respectively, with an overall success rate of 94%.

CONCLUSION

Multiple, sequential, free tissue transfer for reconstruction of head and neck defects is a safe and reliable procedure with success rates equal to that in patients undergoing initial free flap reconstruction. Careful preoperative planning can result in optimal outcomes even in this difficult patient population.

Microsurgical Free Flap Reconstruction Outcomes in Head and Neck Cancer Patients after Surgical Extirpation and Intraoperative Brachytherapy

OBJECTIVES

The management of recurrent or persistent head and neck cancer poses a challenging problem. Salvage surgery for these individuals consists of ablative surgery, interstitial brachytherapy, and microsurgical free flap reconstruction. This study reviews complications after such reconstruction.

METHODS

We reviewed 139 consecutive head and neck cancer patients undergoing free flap reconstruction from January 1994 to May 2002. These included 66 patients with recurrent head and neck cancer undergoing intraoperative brachytherapy (IOBT) and free flap reconstruction and 73 undergoing free flap reconstructions only. A total of 142 reconstructions were performed, with three patients in IOBT group receiving two free flap reconstructions per patient, giving us a total of 69 reconstructions in the IOBT group versus 73 in the non-IOBT group. Nine patients were excluded from the IOBT group because of nonsynchronous use of brachytherapy and reconstruction, and 10 patients were excluded from the other group because they had prior radiotherapy or surgical treatment, leaving us with a total of 123 reconstructions, 60 in the IOBT group and 63 in the non-IOBT group. The IOBT group patients received iodine Vicryl seed implants, palladium seed implants, or both, to deliver an average dose of 79.3 +/- 31.8 Gy (mean +/- 1SD) to the surgical bed.

RESULTS

All patients were followed for evidence of local wound complications. The IOBT group showed multiple complications in 23 (38.33%) of 60 reconstructions, the most common being wound dehiscence in 11. This, when compared with the non-IOBT group complications (15.87%), was found to be statistically significant (chi test, P <.01).

CONCLUSION

IOBT increases the rate of complications in patients undergoing microvascular free tissue transfer. This, however, should not deter or alter the aggressiveness of cancer therapy used for managing recurrent head and neck cancer.

Recipient Vessel Analysis for Microvascular Reconstruction of the Head and Neck

The selection of recipient vessels that are suitable for microvascular anastomosis in the head and neck region is one of many components that is essential for successful free tissue transfer. The purpose of this study was to evaluate a set of factors that are related to the recipient artery and vein and to determine how these factors influence flap survival. A retrospective review of 102 patients over a 5-year consecutive period was completed. Indications for microvascular reconstruction included tumor ablation (n = 76), trauma (n = 13), and chronic wounds or facial paralysis (n = 13). The most frequently used recipient artery and vein included the facial, superficial temporal, superior thyroid, carotid, and jugular. Various factors that were related to the recipient vessels were analyzed and included patient age, recipient artery and vein, diabetes mellitus, tobacco use, the timing of reconstruction, the method of anastomosis, previous radiation therapy, creation of an arteriovenous loop, and use of an interposition vein graft. Successful free tissue transfer was obtained in 97 of 102 flaps (95%). Flap failure was the result of venous thrombosis in 4 and arterial thrombosis in 1. Statistical analysis demonstrated that anastomotic failure was associated with an arteriovenous loop (2 of 5, P = 0.03) and tobacco use (3 of 5, P = 0.03). Flap failure was not related to patient age, choice of recipient vessel, diabetes mellitus, previous irradiation, the method of arterial or venous anastomosis, use of an interposition vein graft, or the timing of reconstruction.

Free flaps for head and neck cancer reconstruction: Does the use of both large cervical vessels as recipient vessels and the employment of end-to-side technique enhance flap survival?

This study specifically investigates whether the use of both large cervical vessels (the external carotid artery and the internal jugular vein) as recipient vessels with end-to-side anastomosis enhance free flap survival in head and neck cancer reconstruction, when compared with the use of other standard smaller neck recipient vessels and end-to-end anastomosis. A total of 84 consecutive patients were included and were divided into two groups (42 in each group) according to the recipient vessels. The overall vessel thrombosis rate was 6% (five of 84 cases) and the overall flap loss rate was 2.4% (two of 84 cases) yielding a flap salvage rate of 60%. Vessel thrombosis occurred in three cases of the smaller vessels group and in two cases of the large cervical vessels group. This was not statistically significant.

Local administration of nitric oxide donor significantly impacts microvascular thrombosis

OBJECTIVES/HYPOTHESIS

Clinical pharmacotherapy has demonstrated a role in preventing microvascular thrombosis in both experimental and clinical settings. Previous studies in the rabbit model have noted an increased rate of thrombosis with intravenous infusion of nitric oxide antagonists. The study assessed the effects of local application of nitric oxide agonists and antagonists on microvascular anastomotic patency rates.

STUDY DESIGN

A randomized, prospective analysis.

METHODS

An arterial inversion graft microvascular thrombosis model was used in New Zealand white rabbits. The rabbits were randomly assigned to nitric oxide agonist, antagonist, and control groups. In each rabbit, the common femoral artery was surgically exposed and a 2-mm arterial inversion graft was harvested. The anastomosis of the graft to the common femoral artery was performed in solutions of either 100 micromol/L spermine NONOate (nitric oxide donor), 100 micromol/L nitro-L-arginine-methyl ester (L-NAME) (nitric oxide synthase inhibitor), or 0.9% sodium chloride (control) solution. The contralateral common femoral artery also underwent arterial inversion graft testing with the use of the same solution. Arterial patency was assessed 1 hour after anastomosis.

RESULTS

Sixteen of 22 arterial inversion grafts performed in the spermine NONOate solution remained patent, and 6 of 22 clotted. Eleven of 21 arterial inversion grafts performed in the control solution remained patent, and 10 clotted. Seven of 21 arterial inversion grafts performed in the L-NAME solution remained patent, and 14 clotted. These results were found to be statistically significant using the chi test with a value of less than.05.

CONCLUSIONS

In the rabbit model, local application of nitric oxide agonists and antagonists can significantly impact anastomotic patency rates. Further studies may demonstrate a role for the clinical use of nitric oxide in microvascular surgery.

Inhibitors of nitric oxide promote microvascular thrombosis

BACKGROUND

Microvascular free tissue transfer is a widely utilized method of head and neck reconstruction. Despite advances in the field, reports of experienced microvascular surgeons on large series of free flap procedures reveal that the incidence of free flap failure varies between 5% and 9%. Most cases of free flap failure are initiated by platelet-mediated events that result in thrombosis at the microvascular anastomoses. Recent evidence indicates that nitric oxide (NO) plays a critical role in preventing thrombosis by inhibiting platelet adhesion and aggregation. The role of NO in microvascular anastomotic thrombosis has not been studied.

OBJECTIVE

To determine the role of NO in microvascular thrombosis using an in vivo rabbit model.

METHODS

An arterial inversion graft (AIG)-induced microvascular thrombosis model was utilized in New Zealand white rabbits. The femoral arteries were used bilaterally to create 3-mm AIGs. Intravenous NO donor, NO inhibitor, or isotonic sodium chloride solution (control) was administered for 1 hour following the completion of the AIG, and vessel patency was then checked using a direct "milking test." Sixteen rabbits (32 AIGs) were used as controls. A potent NO inhibitor, N(w)-nitro-L-arginine methylester (L-NAME), was administered to 13 rabbits (26 AIGs) and L-arginine, a NO precursor/donor, was given to 10 rabbits (20 AIGs).

RESULTS

The control animals had a thrombosis rate of 46.9%. The rate of thrombosis in animals exposed to an NO inhibitor (L-NAME) was significantly higher, at 76.9% (P<.05, chi( 2) = 4.23). The L-arginine group did not show a statistical difference with the control in the rate of thrombosis (50.0%).

CONCLUSIONS

Nitric oxide plays a role in microvascular anastamotic thrombosis. Intravenous NO inhibitors appear to increase the short-term rate of microvascular thrombosis. L-arginine, an NO precursor, does not appear to produce the opposite effect. Further studies using local NO donors and antagonists as well as more potent NO precursors are needed to further evaluate NO's role in microvascular thrombosis. The results of this study may have applications to human microvascular surgery.