Postoperative management of antithrombotic medication in microvascular head and neck reconstruction: a comparative analysis of unfractionated and low-molecular-weight heparin

Free-flap reconstruction methods in head-and-neck oncologic surgery: A CROSS practice survey of members of the French GETTEC Head-and-Neck Tumor Study Group

OBJECTIVE

To survey practices concerning the use of anticoagulants and antiplatelets in microvascular free-flap reconstruction following oncological surgery of the head and neck.

METHODS

A survey of practices was carried out between September 2022 and March 2023. An online questionnaire was sent to members of the French GETTEC Head-and-Neck Tumor Study Group in all French centers practicing head-and-neck cancer surgery with reconstruction using microvascular free-flaps. The questionnaire asked surgeons about their practices regarding the use of intra- and postoperative anticoagulants and antiplatelets, preoperative management of comorbidities, and prevention of postoperative complications.

RESULTS

Sixty-one percent of the 38 respondents (23/38) used intraoperative intravenous heparin injection, associated to flap irrigation with heparin for 76% of surgeons (29/38) and/or a heparin solution bath for 37% (14/38). Postoperative anticoagulation was used by 95% of surgeons (36/38), and antiplatelets by 40% (15/38). Postoperatively, 40% (15/38) carried out monitoring using an implantable micro-Doppler probe, associated to analysis of clinical characteristics of the flap.

CONCLUSION

Reconstructive surgery using microvascular free-flaps involves numerous factors that can influence success. Prospective studies, particularly concerning the management of anticoagulants, could enable a national consensus on methods for free-flap reconstruction.

Successful microvascular surgery in patients with thrombophilia in head and neck surgery: a case series

BACKGROUND

In this case series, a perioperative anticoagulation protocol for microvascular head and neck surgery in patients with thrombophilia is presented. Microvascular free-flap surgery is a standard procedure in head and neck surgery with high success rates. Nevertheless, flap loss-which is most often caused by thrombosis-can occur and has far-reaching consequences, such as functional impairment, prolonged hospitalization, and increased costs. The risk of flap loss owing to thrombosis is significantly increased in patients with thrombophilia. Therefore, perioperative anticoagulation is mandatory. To date, no perioperative anticoagulation protocol exists for these high-risk patients.

CASE PRESENTATION

We present three exemplary male Caucasian patients aged 53-57 years with free flap loss owing to an underlying, hidden thrombophilia.

CONCLUSION

We present a modified anticoagulation protocol for microvascular surgery in these high-risk patients, enabling successful microsurgical reconstruction.

Perioperative anticoagulation in head and neck free flap reconstructions: Experience of an anticoagulative scheme and its modification

OBJECTIVES

Microvascular anastomoses in microvascular reconstructions induce rheological changes in the anastomosed vessels and are usually counteracted by anticoagulative medication. There is no regimen commonly agreed on. This study provides an easy to use anticoagulative regimen.

PATIENTS AND METHODS

Consecutive cases of either anticoagulative regimen between 2013 and 2018 that underwent microvascular reconstruction in the head and neck area were included in this retrospective study, resulting in 400 cases in total. Two different anticoagulative regimens were applied to 200 patients in each group: (a) intraoperatively administered unfractionated 5000 I.U. high molecular weight heparin (HMWH) and postoperatively low molecular weight heparin (LMWH, Enoxaparin) 1 mg/kg/body weight postoperatively and (b) intraoperatively LMWH 0.5 mg/kg/body weight as well as 12 h later and 1 mg/kg/body weight postoperatively.

RESULTS

The LMWH cohort showed fewer overall thromboembolic (8.5% vs. 11%; p = .40) and peripheral thrombotic events (1% vs. 3.5%; p = .18) and lung embolisms (3% vs. 4%; p = .59). The number of thromboses at the site of the anastomosis was equally distributed. In regard to flap-specific complications, LMWH was associated with a positive effect, in particular with respect to total flap losses (5% vs. 7%; p = .40) and wound-healing disorders (14.5% vs. 20%; p = .145).

CONCLUSION

Findings indicate that intra- and postoperatively administered LMWH as the only anticoagulative medication seems reliable in our clinical routine of head and neck free flap reconstructions.

High-pressure infusion improves multi-territory perforator flap viability via choke artery dilation: A preliminary study in a rat model

BACKGROUND

Multi-territory perforator flaps have become the preferred option for the repair and reconstruction of large soft tissue defects. Although methods (e.g., pharmacological agents, mechanical stimulation, and thermal stimulation) were developed to open choke vessels to improve flap survival, the flap necrosis rate is still as high as 28.8%. The authors hypothesized that high-pressure infusion might enhance flap viability by dilating choke arteries intraoperatively in a rat model of multi-territory perforator flap.

METHODS

Two-month-old male Sprague-Dawley rats were randomized into two groups (n = 32 each). During the multi-territory perforator flap elevation based on the right superficial epigastric angiosome, one group received continuous high-pressure infusion (mean pressure, 250 mmHg; duration, 1 min) of an isotonic heparin sodium solution (12,500 U/L) via the artery in the pedicle, whereas the other group received no infusion. At 7 days postoperatively, arteriography was performed; endothelial nitric oxide synthase (eNOS) and vascular endothelial growth factor (VEGF) expression and microvascular density were evaluated by western blot and histology, respectively; and flap survival was compared. Moreover, intraluminal diameters were examined at 1 day and 7 days postoperatively using hematoxylin and eosin staining, and coagulation function was assessed immediately postoperatively.

RESULTS

High-pressure infusion significantly promoted the dilation of choke arteries at 1 day and 7 days postoperatively. It also increased eNOS and VEGF expression, flap survival, and microvascular density. The coagulation function remained unaffected.

CONCLUSIONS

High-pressure infusion allowed intraoperative and postoperative dilation of the choke arteries that enhanced the viability of multi-territory perforator flaps in rats.

Acetylsalicylic Acid is Not Associated With Improved Clinical Outcomes After Microsurgical Breast Reconstruction

INTRODUCTION

Microvascular thrombosis with resultant flap loss remains a devastating complication in autologous breast reconstruction. While acetylsalicylic acid (ASA) for prevention of microvascular thrombosis is commonly administered postoperatively, clinical evidence supporting this practice remains insufficient. Here, we investigate the association of postoperative ASA administration with differences in clinical outcomes following microsurgical breast reconstruction.

METHODS

A prospectively maintained database was queried to identify patients who had undergone microsurgical breast reconstruction. Patients were categorized based on whether they had received postoperative ASA for 30 d (Group 1) or had not received ASA (Group 2). Patient demographics, reconstructive outcomes, complications, and transfusion requirements were retrieved.

RESULTS

One hundred thirty six patients with a mean age of 49.5 y and a mean body mass index of 28.5 kg/m² who had undergone a total of 216 microsurgical breast reconstructions were included. No significant differences were noted with regard to patient demographics with the exceptions of increased rates of neoadjuvant chemotherapy and delayed reconstruction in Group 1. There were no significant differences in the rates of postoperative complications including breast hematoma, mastectomy skin flap necrosis, partial flap necrosis, seroma, and deep venous thrombosis between patients who did or did not receive ASA postoperatively. Similarly, no difference was noted regarding postoperative blood transfusion rates (Group 1: 9.9% versus Group 2: 9.1%; P = 0.78). Finally, patients in Group 1 had significantly longer hospital stays (Q1 = 4, median = 4.5, Q3 = 5).

CONCLUSIONS

Postoperative ASA administration is not associated with improved postoperative clinical outcomes. The use of ASA routinely after autologous breast reconstruction does not appear to be a necessity in practice.

Effect of Perioperative Antithrombotics on Head and Neck Microvascular Free Flap Survival After Anastomotic Revision

OBJECTIVE

To determine if antithrombotic therapy improves head and neck microvascular free flap survival following anastomotic revision.

STUDY DESIGN

A retrospective review of all patients with microvascular free tissue transfer to the head and neck between August 2013 and July 2021.

SETTING

Otolaryngology-Head and Neck Surgery Departments at University of Alabama at Birmingham, University of Colorado, and University of California Irvine.

METHODS

Perioperative use of anticoagulation, antiplatelets, intraoperative heparin bolus, tissue plasminogen activator (tPA) and vasopressor use, and leech therapy were collected plus microvascular free flap outcomes. The primary endpoint was free flap failure. Analyses of free flaps that underwent anastomotic revision with or without thrombectomy were performed.

RESULTS

A total of 843 microvascular free flaps were included. The overall rate of flap failure was 4.0% (n = 34). The overall rate of pedicle anastomosis revision (artery, vein, or both) was 5.0% (n = 42) with a failure rate of 47.6% (n = 20) after revision. Anastomotic revision significantly increased the risk of flap failure (odds ratio [OR] 52.68, 95% confidence interval [CI] [23.90, 121.1], p < .0001) especially when both the artery and vein were revised (OR 9.425, 95% CI [2.117, 52.33], p = .005). Free flap failure after the anastomotic revision was not affected by postoperative antiplatelet therapy, postoperative prophylactic anticoagulation, intraoperative heparin bolus, tPA, and therapeutic anticoagulation regardless of which vessels were revised and if a thrombus was identified.

CONCLUSION

In cases of microvascular free tissue transfer pedicle anastomotic revision, the use of antithrombotic therapy does not appear to significantly change free flap survival outcomes.

Does anticoagulation improve outcomes of microvascular free flap reconstruction following head and neck surgery: a systematic review and meta-analysis

The commonest cause of microvascular free flap failure is thrombosis at the anastomosis. Pharmacological antithrombotic therapies have been used to mitigate this risk, but they carry the risk of bleeding and haematoma formation. To justify any intervention, it is necessary to evaluate the benefits and balance of risks. This meta-analysis aims to quantify the value of systemic anticoagulation during head and neck free tissue reconstruction. We performed a systematic review on the impact of additional prophylactic antithrombotic therapy on head and neck (H&N) free tissue transfer (on top and above the use of low molecular weight heparin to prevent deep vein thrombosis). We carried a PRISMA-guided literature review, following registration with PROSPERO. All studies analysing the possible impact of prophylactic anticoagulants on free flap surgery in the head and neck were eligible. The primary outcome was perioperative free flap complications (perioperative thrombosis, partial or total free flap failure, thrombo-embolic events, or re-exploration of anastomosis). Secondary outcomes included haematoma formation or bleeding complications requiring further intervention. We identified eight eligible studies out of 454. These included 3531 free flaps for H&N reconstruction. None of the assessed interventions demonstrated a statistically significant improvement in free flap outcomes. Accumulative analysis of all anti-coagulated groups demonstrated an increased relative risk of free flap complications [RR 1.54 (0.73-3.23)] compared to control albeit not statistically significant (p = 0.25). Pooled analysis from the included studies showed that the prophylactic use of therapeutic doses of anticoagulants significantly (p = 0.003) increased the risk of haematoma and bleeding requiring intervention [RR 2.98 (1.47-6.07)], without reducing the risk of free flap failure. Additional anticoagulation does not reduce the incidence of free flap thrombosis and failure. Unfractionated heparin (UFH) consistently increased the risk of free flap complications. The use of additional anticoagulation as 'prophylaxis' in the perioperative setting, increases the risk of haematoma and bleeding.

Aspirin, heparin and ischemia time in microvascular free flap surgery - their influence and an optimal anticoagulation protocol

BACKGROUND

Microvascular surgery has become a standardized technique for reconstruction of large tissue defects in Head and Neck Reconstructive Surgery. However, the main dreaded complications are thrombosis of blood vessels or major bleeding after surgery. Several different anticoagulation protocols have been established in the last decades to overcome these problems with varying degrees of success.

METHODS

Over a period of six years, a standardized anticoagulation protocol including acetylsalicylic acid (ASA) and unfractionated heparin (UFH) for direct intraoperative and postoperative administration was established, optimized and compared to a previously used non-standardized protocol. A total of 178 flap surgeries were included in the development and optimization process of the protocol.

RESULTS

ASA significantly increased the risk of complications when used for longer than 72 h (OR = 2.52; p = 0.002; 95% CI 1.39-4.59). Administration of UFH reduced flap loss (bolus: OR 0.68; p = 0.47; 95% CI 0.24-1.93; continuous UFH administration: OR = 0.61; p = 0.33; 95% CI 0.22-1.66), however doses greater than 500 IU/ h of UFH as continuous infusion increased the risk of complications. Reduction in ischemia time had no effect on the occurrence of complications.

CONCLUSION

Anticoagulation regimes in microvascular surgery can influence the postoperative complication rate. The optimal protocol should consist of a combination of ASA and UFH for the intraoperative and direct postoperative phase. Prolonged administration of ASA as well as doses &gt;500 IU/ h of UFH are to be avoided due to the increased complication rate.

Unplanned reoperation after radical surgery for oral cancer: an analysis of risk factors and outcomes

Background

Unplanned reoperation (UR) after radical surgery for oral cancer (OC) is a health threat for the patients. The aim of the study was to identify the incidence of and risk factors for unplanned reoperation following oral cancer radical surgery, and to explore a potential role for long-term survival.

Methods

The present study followed a retrospective study design. Univariate and multivariate analyses were used to identify risk factors for demographic and clinical characteristics of patients. Survival analysis was performed by the Kaplan–Meier method. The data was analyzed statistically between November and December 2021.

Results

The incidence of UR was 15.7%. The primary cause of UR was reconstructed flap complications. Multivariate logistic regression analyses revealed that diabetes, tumor size, type of reconstruction, and nodal metastasis were independent risk factors for UR. Patients undergoing UR had a longer hospitalization, more post-operative complications, and a higher mortality compared with the non-UR group. UR is negatively correlated with the cancer-specific survival rate of patients (Log-rank test, P = 0.024).

Conclusion

Diabetes, tumor size, pedicled flap reconstruction and cervical nodal metastasis (N2) as independent risk factors for UR was discovered. UR was positively correlated with perioperative complications prolong hospital stay, and increased early mortality, but negatively correlated with the cancer-specific survival rate survival rate.