Hypothermia During Microsurgical Head and Neck Reconstruction and Incidence of Venous Thromboembolism.

Importance: Venous thromboembolism (VTE) is a severe complication after microsurgical free tissue transfer (FTT) to the head and neck. Hypothermia during surgery is a modifiable risk factor, and avoiding it may reduce the postoperative VTE rate.

Objective: To assess the association between hypothermia (temperature <36 °C) and postoperative VTE and free flap pedicle thrombosis rates after head and neck reconstruction with FTT.

Computer-Aided Design and Manufacturing in Free Fibula Reconstruction of the Mandible: Comparison of Long-Term Outcomes with the Conventional Technique.

Background: Pre-operative computer-aided design and manufacturing (CAD/CAM) revolutionized head and neck reconstruction after extirpative surgery. However, studies performing head-to-head comparison to the conventional technique have limited long-term follow-up. We aimed to compare short and long-term outcomes between conventional and CAD/CAM approaches for mandibular reconstruction with free fibula flaps.

Impact of Preoperative Multidisciplinary Conference on Head and Neck Reconstruction Outcomes.

Introduction: Head and neck oncologic resections with microvascular reconstruction are lengthy and complex procedures with inefficiencies in the operating room (OR) associated with increased complications and higher costs. Multidisciplinary care has become increasingly used to provide improved care for complex patients; however, the potential role of this has not yet been studied in head and neck microvascular free flap procedures.

Methods: Patients between 2016 and 2022 treated before and after implementation of the conference were included.

Long-term outcomes in virtual surgical planning for mandibular reconstruction: A cost-effectiveness analysis.

Objective: This study is an economic evaluation comparing virtual surgical planning (VSP) utilization to free hand mandibular reconstruction (FHR) for advanced oral cavity cancer, for which the cost effectiveness remains poorly understood. The proposed clinical benefits of VSP must be weighed against the additional upfront costs.

Methods: A Markov decision analysis model was created for VSP and FHR based on literature review and institutional data over a 35-year time horizon.

The Future of Microsurgery: Vascularized Composite Allotransplantation and Engineering Vascularized Tissue.

Background: Microsurgical techniques have revolutionized the field of reconstructive surgery and are the mainstay for complex soft tissue reconstruction. However, their limitations have promoted the development of viable alternatives. This article seeks to explore technologies that have the potential of revolutionizing microsurgical reconstruction as it is currently known, reflect on current and future vascularized composite allotransplantation (VCA) practices, as well as describe the basic science within emerging technologies and their potential translational applications.

A Model to Study Wound Healing Over Exposed Avascular Structures in Rodents With a 3D-Printed Wound Frame.

Background: Soft tissue defects with exposed avascular structures require reconstruction with well-vascularized tissues. Extensive research is ongoing to explore tissue engineered products that provide durable coverage. However, there is a lack of controlled and affordable testbeds in the preclinical setting to reflect this challenging clinical scenario.

Topical Tacrolimus and Mycophenolic Acid Therapy Synergizes with Low Dose Systemic Immunosuppression to Sustain Vascularized Composite Allograft Survival.

Aim: The goal of this study was to evaluate whether topical administration of tacrolimus (TAC) and mycophenolic acid (MPA) at the transplant site enables vascularized composite allograft (VCA) survival with significant minimization of the dose and adverse effects of systemic TAC (STAC) immunosuppression.

Materials And Methods: Lewis (Lew) rats received orthotopic hind limb allotransplants from fully mismatched Brown Norway (BN) donors. Group 1 (Controls) received no treatment.

Nerve Wrap for Local Delivery of FK506/Tacrolimus Accelerates Nerve Regeneration.

Peripheral nerve injuries (PNIs) occur frequently and can lead to devastating and permanent sensory and motor function disabilities. Systemic tacrolimus (FK506) administration has been shown to hasten recovery and improve functional outcomes after PNI repair. Unfortunately, high systemic levels of FK506 can result in adverse side effects.

Machine Perfusion Deters Ischemia-Related Derangement of a Rodent Free Flap: Development of a Model.

Introduction: Machine perfusion can enable isolated support of composite tissues, such as free flaps. The goal of perfusion in this setting is to preserve tissues prior to transplantation or provide transient support at the wound bed. This study aimed to establish a rodent model of machine perfusion in a fasciocutaneous-free flap to serve as an affordable testbed and determine the potential of the developed support protocol to deter ischemia-related metabolic derangement.

Co-surgery in head and neck microvascular reconstruction.

Purpose: Co-surgery with two attending reconstructive surgeons is becoming increasingly common in breast microvascular reconstruction due to case complexity and the potential for improved outcomes and operative efficiency. The impact of co-surgery on outcomes in head and neck microvascular reconstruction has not been studied.

Methods: Our multidisciplinary head and neck reconstruction team (Otolaryngology, Plastic Surgery) at the University of Pittsburgh transitioned to a practice of co-surgery on head and neck free flaps.

Local Delivery of Adipose Stem Cells Promotes Allograft Survival in a Rat Hind-Limb Model of Vascularized Composite Allotransplantation.

Background: Adipose stem cells (ASCs) are a promising cell-based immunotherapy because of their minimally invasive harvest, high yield, and immunomodulatory capacity. In this study, the authors investigated the effects of local versus systemic ASC delivery on vascularized composite allotransplant survival and alloimmune regulation.

Methods: Lewis rats received hind-limb transplants from Brown Norway rats and were administered donor-derived ASCs (passage 3 or 4, 1 × 10 6 cells/rat) locally in the allograft, or contralateral limb, or systemically at postoperative day 1.

Functional outcomes of hyoid suspension in anterior oromandibular reconstruction.

Background: Hyoid suspension can be considered in major oromandibular reconstruction. The impact of hyoid suspension on flap viability, swallowing outcomes, airway, and long term radiographic hyoid position is unknown. The objective of this study is to describe outcomes after hyoid suspension in anterior mandibular reconstruction with fibular free flaps.

Venous Thromboembolism Rates After Free Flap Reconstruction of the Head and Neck Region.

Background: Venous thromboembolism (VTE) is a major concern for the postoperative hospitalized patient, especially after long and complex procedures. Cancer itself also contributes to the hypercoagulable state, further complicating the management of patients. Despite prophylaxis, breakthrough events can occur.

Discharge Disposition After Head and Neck Reconstruction: Effect on Adjuvant Therapy and Outcomes.

Objectives: Head and neck cancer patients that require major reconstruction often have advanced-stage disease. Discharge disposition of patients can vary and impact time to adjuvant treatment. We sought to examine outcomes in patients discharged to skilled nursing facilities (SNF) compared to those discharged home, including the impact on adjuvant therapy initiation and treatment package time (TPT).

Biodegradable Nerve Guide with Glial Cell Line-Derived Neurotrophic Factor Improves Recovery After Facial Nerve Injury in Rats.

Bioengineered nerve guides with glial cell line-derived neurotrophic factor (GDNF) support recovery after facial nerve injury by acting as regenerative scaffolds. To compare functional, electrophysiological, and histological outcomes after repair of rat facial nerve transection in control, empty nerve guide, and nerve guide with GDNF conditions. Rats underwent transection and primary repair of the buccal branch of the facial nerve and were divided into (1) transection and repair only, (2) transection and repair augmented with empty guide, (3) transection and repair augmented with GDNF-guide groups.

Donor derived hematopoietic stem cell niche transplantation facilitates mixed chimerism mediated donor specific tolerance.

Compelling experimental evidence confirms that the robustness and longevity of mixed chimerism (MC) relies on the persistence and availability of donor-derived hematopoietic stem cell (HSC) niches in recipients. Based on our prior work in rodent vascularized composite allotransplantation (VCA) models, we hypothesize that the vascularized bone components in VCA bearing donor HSC niches, thus may provide a unique biologic opportunity to facilitate stable MC and transplant tolerance. In this study, by utilizing a series of rodent VCA models we demonstrated that donor HSC niches in the vascularized bone facilitate persistent multilineage hematopoietic chimerism in transplant recipients and promote donor-specific tolerance without harsh myeloablation.

Association between venous thromboembolism rates and different prophylactic anticoagulation regimens in patients undergoing free flap reconstruction of the head and neck region.

Background: Venous Thromboembolism (VTE) is a serious complication after free tissue transfer to the head and neck (H&N). However, an optimal antithrombotic prophylaxis protocol is not defined in the literature. Enoxaparin 30 mg twice daily (BID) and heparin 5000 IU three times daily (TID) are among the most commonly used regimens for chemoprophylaxis.

Automated Decellularization of the Rodent Epigastric Free Flap: A Comparison of Sodium Dodecyl Sulfate-Based Protocols.

Background:  Free tissue transfer to cover complex wounds with exposed critical structures results in donor-site morbidity. Perfusion decellularization and recellularization of vascularized composite tissues is an active area of research to fabricate complex constructs without a donor site. Sodium dodecyl sulfate (SDS)-based protocols remain the predominant choice for decellularization despite the deleterious effects on tissue ultrastructure and capillary networks.

Cortical reintegration after facial allotransplantation.

Neural plasticity of the brain or its ability to reorganize following injury has likely coincided with the successful clinical correction of severe deformity by facial transplantation since 2005. In this study, we present the cortical reintegration outcomes following syngeneic hemifacial vascularized composite allograft (VCA) in a small animal model. Specifically, changes in the topographic organization and unit response properties of the rodent whisker-barrel somatosensory system were assessed following hemifacial VCA.

Assessment of BMI and Venous Thromboembolism Rates in Patients on Standard Chemoprophylaxis Regimens After Undergoing Free Tissue Transfer to the Head and Neck.

Importance: Venous thromboembolism (VTE) is a severe complication after free tissue transfer to the head and neck (H&N). Enoxaparin 30 mg twice daily (BID) is a common regimen for chemoprophylaxis. However, differences in enoxaparin metabolism based on body weight may influence its efficacy and safety profile.

The Role of Autologous Fat Grafting in Rhinoplasty.

Rhinoplasty is one of the most popular aesthetic surgeries worldwide and often includes grafting techniques to achieve optimal results. One of these grafting techniques is autologous fat transfer, which has been used to increase volume, camouflage irregularities, and/or improve the quality of the nasal skin-soft tissue envelope. Moreover, minimally invasive approaches for altering the nasal appearance have recently increased and become known as "liquid" or "nonsurgical rhinoplasty.