Arteriovenous loops in microsurgical free tissue transfer in reconstruction of central sternal defects

The free vastus lateralis-And conjoined vastus lateralis anterolateral thigh/tensor fascia lata flap for oncological chest wall reconstruction

INTRODUCTION

A reconstructive option for extensive chest wall reconstruction is the free myocutaneous vastus lateralis muscle (VL) flap which can be performed in isolation or in conjunction with a fasciocutaneus anterolateral thigh (cVLALT) and/or myofasciocutaneous tensor fascia lata flap (cVLTFL). We aimed to directly compare the outcomes of these reconstructive options.

METHODS

Patients who underwent oncological chest wall reconstruction with a free VL, cVLALT, or cVLTFL flap between February 2010 and 2022 were included in this retrospective study. Patient demographics, surgical characteristics, as well as medical and reconstructive outcomes, were evaluated. The operative outcomes between myocutaneous VL, cVLALT, and cVLTFL flap reconstructions were compared.

RESULTS

A total of 41 patients underwent chest wall reconstruction with a free myocutaneous VL (n = 25; 61%), cVLALT (n = 14; 34%), or cVLTFL Three acute flap thromboses occurred in the entire cohort (3/41, 7%), with one myocutaneous VL flap failing because of recurrent venous thrombosis during the salvage procedure. Total flap necrosis was seen in two cases (5%; VL flap: n = 1; cVLALT flap: n = 1), and partial flap necrosis in one VL flap (1/25, 4%) and in the distal ALT portion of three cVLALT flaps (3/14, 21%). No significant difference was seen between isolated VL and conjoined VL flaps regarding the partial (p = .28) or total flap necrosis rate (p = .9).

CONCLUSION

The free (conjoined) VL flap provides reliable outcomes for obliterating dead space achieving durable reconstruction of complex chest wall defects.

Microsurgical reconstruction using thoracoacromial vessels as recipients for complicated chest wall defects

BACKGROUND

Free tissue transfer is often required for the reconstruction of complex and deep anterior chest wall wounds, for which the identification of suitable recipient vessels is crucial. Although the internal mammary arteries (IMAs) are a representative option, identifying secondary options when these vessels are compromised remains a challenge. This report evaluated the efficacy of using the thoracoacromial vessels (TAVs) as recipients for chest wall reconstruction by reviewing our experience.

METHODS

We conducted a retrospective review of patients undergoing free-flap-based chest wall reconstruction using TAVs as recipient vessels from February 2020 to March 2023. Patient demographics and surgery-related characteristics data were collected. The primary outcome of interest was the occurrence of flap perfusion-related complications.

RESULTS

In total, 12 cases utilized TAVs as recipients, primarily for defects following sternotomy, where bilateral IMA was unavailable due to prior surgery. The TAVs with reliable perfusion were consistently identified beneath the pectoralis major muscle. The anterolateral thigh flap was predominantly employed, with musculocutaneous or chimeric flaps introduced for bony defects. The mean pedicle length of the harvested flap was 7.2 cm (range, 3-13), and in cases with a vascular gap, the pedicle was extended using an arteriovenous interposition graft. This resulted in a mean pedicle length needed to reach recipient vessels of 9.9 cm (range, 6.5-19). All flaps survived, with only one experiencing partial necrosis.

CONCLUSIONS

The TAV could be considered as an attractive alternative recipient vessel in microsurgical reconstruction of complicated chest wall defects when the use of IMA is not feasible.

Free Flap Reconstruction of Sternal Defects after Cardiac Surgery: An Algorithmic Approach for Dealing with Sparse Recipient Vessels

Background

Sparsity of recipient vessels poses a challenge for microsurgical free flap reconstruction of sternal defects following deep sternal wound infection after cardiac surgery.

Methods

From January 2013, a standardized algorithm for dealing with sparse recipient vessels was strictly followed. In this retrospective study including 75 patients, we compared operative details, surgical complications, and reconstructive outcomes of patients treated according to this algorithm (group A: January 2013-May 2021; n = 46) with a historical control group (group B: January 2000-December 2012, n = 29).

Results

The left internal mammary artery had been harvested for arterial bypass grafting in 40 of 46 cases (87%) in group A and in all cases in group B. The right internal mammary artery (RIMA) and right internal mammary vein (RIMV) were the first choice as recipient vessels. In case of unsuitability of the RIMV, a right cephalic vein (CV) turndown was used for venous outflow. If both RIMA and RIMV proved insufficient, a single-stage arterio-venous loop (AVL) between the CV and subclavian artery (CV-SA AVL), CV and thoracoacromial artery (CV-TA AVL), or subclavian artery and subclavian vein (SA-SV AVL) was established. The algorithmic approach significantly reduced partial flap necrosis [group A: n = 3 (7%) versus group b: n = 7 (24%); P = 0.04], and overall operation time [group A: 360 ± 88 min versus group B: 415 ± 80 min; P = 0.01].

Conclusions

Standardized approaches improve clinical outcomes in microsurgical free flap sternal reconstruction after cardiac surgery.

Free Flaps in Sternal Osteomyelitis After Median Sternotomy: A Center's 12-Year Experience

BACKGROUND

 Adequate treatment of deep sternal wound infections (DSWIs) after open thoracic surgery still presents a major challenge. This study retrospectively analyzes the results of a single center's 12-year experience in treating DSWI, with special emphasis on free flap reconstruction.

METHODS

 In this single-center, retrospective study, all patients admitted with the diagnosis of DSWI after open thoracic surgery between 2009 and 2020 were included. A comparative analysis was performed between: (1) pedicled versus free flaps, (2) the center's two workhorse flaps-the pedicled latissimus dorsi (pLD) versus free anterolateral thigh (fALT) flaps, as well as (3) myocutaneous (MC) versus fasciocutaneous (FC) flaps. Primary endpoints were length of hospital stay (LOS) after reconstruction and in-hospital mortality.

RESULTS

 Of a total of 165 patients included, 152 underwent DSWI defect reconstruction with a total of 12 different reconstruction methods. Although the defect size was larger in patients who underwent free flap coverage, and the risk profile in the fALT and FC flap groups was higher, the LOS after reconstruction (in days) did not differ significantly between the groups (pedicled vs. free flaps: 23 vs. 28, p > 0.05; pLD vs. fALT: 24.5 vs. 26, p > 0.05; MC vs. FC flaps: 23 vs. 26, p > 0.05). Also, no significant differences were found in terms of in-hospital mortality when comparing the groups (pedicled vs. free flaps: 11.2 vs. 17.4%, p > 0.05; pLD vs. fALT: 11.5 vs. 12.5%, p > 0.05; MC vs. FC flaps: 12.9 vs. 12.5%, p > 0.05).

CONCLUSION

 With proper patient selection, free tissue transfer is a valuable alternative in the treatment of sternal dehiscence after a DSWI. Furthermore, our data demonstrate that MC flaps are not necessarily superior to FC flaps in the reconstruction of sternal osteomyelitis defects.

Analysis of vein grafting versus arteriovenous loop in microvascular head and neck reconstruction: Multicenter series of 36 patients

BACKGROUND

The utilization of an arteriovenous loop is an underreported technique that affords the creation of reliable vascular options. Understanding the efficacy and impacting variables of microvascular reconstruction with an arteriovenous loop can be critical to its use.

METHODS

Multi-institutional study of 36 patients who underwent vein grafting or AV loop with free tissue transfer.

RESULTS

58.3% of patients received prior radiation and 38.9% prior flap reconstruction. Flap success for vein grafting was 76% and AV loop was 100% (p = 0.16). Success for the radiated cohort was 90.5% and non-radiated 80% (p = 0.63). Flap success for the radiated, vein grafted patient was 83.3% and 100% flap success rate for radiated, AV loop patient (p = 0.49). Overall flap survival was 83.3% versus 97% overall success rate in the United States.

CONCLUSION

The AV loop is a viable modality for vessel-depleted free tissue reconstruction. Radiation and previous surgery do not significantly impact flap success rates.

Efficient bone regeneration of BMP9-stimulated human periodontal ligament stem cells (hPDLSCs) in decellularized bone matrix (DBM) constructs to model maxillofacial intrabony defect repair

BACKGROUND

BMP9-stimulated DPSCs, SCAPs and PDLSCs are effective candidates for repairing maxillofacial bone defects in tissue engineering, while the most suitable seed cell source among these three hDMSCs and the optimal combination of most suitable type of hDMSCs and BMP9 have rarely been explored. Moreover, the orthotopic maxillofacial bone defect model should be valuable but laborious and time-consuming to evaluate various candidates for bone regeneration. Thus, inspired from the maxillofacial bone defects and the traditional in vivo ectopic systems, we developed an intrabony defect repair model to recapitulate the healing events of orthotopic maxillofacial bone defect repair and further explore the optimized combinations of most suitable hDMSCs and BMP9 for bone defect repair based on this modified ectopic system.

METHODS

Intrabony defect repair model was developed by using decellularized bone matrix (DBM) constructs prepared from the cancellous part of porcine lumbar vertebral body. We implanted DBM constructs subcutaneously on the flank of each male NU/NU athymic nude mouse, followed by directly injecting the cell suspension of different combinations of hDMSCs and BMP9 into the central hollow area of the constructs 7 days later. Then, the quality of the bony mass, including bone volume fraction (BV/TV), radiographic density (in Hounsfield units (HU)) and the height of newly formed bone, was measured by micro-CT. Furthermore, the H&E staining and immunohistochemical staining were performed to exam new bone and new blood vessel formation in DBM constructs.

RESULTS

BMP9-stimulated periodontal ligament stem cells (PDLSCs) exhibited the most effective bone regeneration among the three types of hDMSCs in DBM constructs. Furthermore, an optimal dose of PDLSCs with a specific extent of BMP9 stimulation was confirmed for efficacious new bone and new blood vessel formation in DBM constructs.

CONCLUSIONS

The reported intrabony defect repair model can be used to identify optimized combinations of suitable seed cells and biological factors for bone defect repair and subsequent development of efficacious bone tissue engineering therapies.

Combined pectoralis and rectus abdominis flaps are associated with improved outcomes in sternal reconstruction

BACKGROUND

Mortality increases nearly 5-fold in the approximately 5% of patients who develop sternal wound complications after cardiothoracic surgery. Flap-based reconstruction can improve outcomes by providing well-vascularized soft tissue for potential space obliteration, antibiotic delivery, and wound coverage; however, reoperation and readmission rates remain high. This study used the high case volume at a tertiary referral center and a diverse range of reconstructive approaches to compare various types of flap reconstruction. Combined (pectoralis and rectus abdominis) flap reconstruction is hypothesized to decrease sternal wound complication-related adverse outcomes.

METHODS

A retrospective cohort study of consecutive adult patients treated for cardiothoracic surgery sternal wound complications between 2008 and 2018 was performed. Patient demographics, comorbidities, wound characteristics, surgical parameters, and perioperative data were collected. Multivariable regression modeling with stepwise forward selection was used to characterize predictive factors for sternal wound-related readmissions and reoperations.

RESULTS

In total, 215 patients were assessed for sternal wound reconstruction. Patient mortality at 1 year was 12.4%. Flap selection was significantly associated with sternal wound-related readmissions (P = .017) and reoperations (P = .014). Multivariate regression demonstrated rectus abdominis flap reconstruction independently predicted increased readmissions (odds ratio 3.4, P = .008) and reoperations (odds ratio 2.9, P = .038). Combined pectoralis and rectus abdominis flap reconstruction independently predicted decreased readmissions overall (odds ratio 0.4, P = .031) and in the deep sternal wound subgroup (odds ratio 0.1, P = .033).

CONCLUSION

Although few factors can be modified in this complex highly comorbid population with a challenging and rare surgical problem, consideration of a more surgically aggressive multiflap reconstructive approach may be justified to improve outcomes.

Free extended anterolateral thigh myocutaneous flap versus combined pedicled pectoralis major-latissimus dorsi myocutaneous flaps in deep and extensive sternal wound reconstruction

BACKGROUND

The combined pedicled pectoralis major-latissimus dorsi (PM-LD) and free extended anterolateral thigh (ALT) myocutaneous flaps provide well-vascularized tissues for extensive sternal wound reconstruction. However, the outcomes and postoperative complications between the two surgical techniques are different. Thus, the aim of this study is to evaluate the feasibility of these two reconstructive options.

METHODS

This single-center, retrospective study was conducted between August 2011 and May 2019. Forty-four patients diagnosed with deep sternal wound infection (DSWI) and presented with grade four complications (sternal instability and necrotic bone tissue) were enrolled. Two reconstructive strategies, namely, combined pedicled PM-LD (n = 24) and free extended ALT (n = 20) myocutaneous flaps, were used according to the patients' hemodynamics. Data including age, gender, body mass index (BMI), hospital stay, follow-up, defect/flap size, number of surgical procedures before reconstruction, duration from the last debridement to flap coverage, comorbidities, and postoperative complications, were obtained for statistical analysis.

RESULTS

The mean defect size in the combined PM-LD myocutaneous flap group was 188.4 (5*17-10*23) cm² , and the mean flap size was 150.0 (8*12-15*15) cm² and 205.0 (8*15-10*25) cm² in PM and LD flap, respectively. The mean defect size in the free extended ALT myocutaneus flap group was 202.5 (6*16-10*21) cm² , and the mean flap size was 285.2 (9*30-12*25) cm² . No significant differences were observed between the free extended ALT and the combined pedicled PM-LD myocutaneous flaps in relation to age, gender, BMI, hospital days, follow-up, defect size, preoperative procedures, and comorbidities, except for the average operative time (443.2 ± 31.2 vs. 321.3 ± 54.3 mins, p = .048). The combined pedicled PM-LD myocutaneous flap had significantly more donor site complications, including seroma (21% vs. 0%, p = .030), bilateral nipple-areolar complex asymmetry (100% vs. 0%, p < .0001), and skin graft loss with infection (33% vs. 0%; p = .044) than the free extended ALT myocutaneous flap.

CONCLUSION

The free extended ALT and the combined pedicled PM-LD myocutaneous flaps were both feasible and effective options for sternal wound reconstruction. Our findings suggested that the free extended ALT myocutaneous flap may be a better alternative for a comprehensive and extensive reconstruction of sternal wounds. Further studies based on these findings can be conducted.

Free Flap Reconstruction of Posterior Trunk Soft-Tissue Defects: Single-Institution Experience and Systematic Literature Review

BACKGROUND

The posterior trunk is a technically demanding location for microvascular free tissue transfer. In this study, the authors report their own institutional experience with soft-tissue free flap reconstruction of the posterior trunk and provide a systematic review of the literature regarding this uncommon clinical scenario.

METHODS

A systematic review was performed using the PubMed database in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A single-institution retrospective review was also performed including all patients who received a soft-tissue free flap for a posterior trunk defect between 1990 and 2019.

RESULTS

The database search yielded 15 articles, representing 61 patients; the most commonly used flap was the latissimus dorsi (45.9 percent) and the most commonly reported defect location was the lumbosacrum (42.3 percent). Retrospective review of the authors' database identified 26 patients, with the latissimus dorsi being the most common flap and the sacrum the most common defect site. The authors' institutional case series showed a 30.7 percent major complication rate and 7.7 percent total flap loss rate; 38.4 percent of flaps required vein grafting.

CONCLUSIONS

In this study, the authors provided a systematic literature review and described their own long-term institutional experience with these rare and difficult reconstructions. Although the overall complication rate is high, these reconstructions are frequently necessary, and an algorithmic approach can improve outcomes.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Potential Complications With Cryopreserved Cadaveric Veins in Arteriovenous Loop Formation for Head and Neck Microvascular Reconstruction

ABSTRACT

Vessel depletion in the head and neck from radiation or previous surgical intervention adds to the operative complexity by limiting reconstructive options. Arteriovenous (AV) loop vascular grafts provide a conduit to bypass these nonviable local vessels to provide adequate blood flow. In certain situations, autologous donor vascular options are deficient or not readily available for creation of the AV loop. Cadaveric vein grafts provide an alternative option in these circumstances, but the efficacy and safety has not yet been delineated. In this study we discuss our experience utilizing cryopreserved cadaveric vein grafts for AV loop creation in head and neck reconstruction. In our initial cohort we aim to elucidate potential challenges and complications associated with the use of cadaveric vein grafts.

Common Carotid-to-Internal Jugular Arteriovenous Loop for Single-Stage Microsurgical Reconstruction in the Radiated Vessel-Depleted Neck

ABSTRACT

Management of head and neck defects in a radiated field can be quite challenging owing to the dearth of vasculature and significant degree of post-radiation fibrosis. In this setting, arteriovenous (AV) loop vascular grafts can bypass nonviable local vessels to provide viable and reliable inflow and outflow vessels for free tissue transfer in an otherwise hostile environment. Prior reports of the Corlett loop utilizing a cephalic vein transposition has been described however a common carotid-to-internal jugular AV loop has not been recently reported. Three patients underwent carotid artery to internal jugular vein AV loop creation to facilitate free-flap reconstruction secondary to radiation-induced vessel depletion. The specific technique described utilizes the saphenous vein as a donor and spares the cephalic vein for the possibility of flap complication. All three cases resulted in successful reconstruction, maintaining healthy tissue, vascular flow, and flap viability at all follow-up intervals. In our experience, vascular augmentation via AV loop formation provides reliable vascular inflow and outflow in the vessel-depleted neck to facilitate microvascular reconstruction. Sparing the cephalic vein yields an additional salvage mechanism in the event of venous congestion.

Extending the Indication of the Superior Thyroid Artery as a Recipient Vessel for Complex Upper Body Defects

BACKGROUND

Reconstruction of complex chest and upper back defects can pose a challenge to microsurgeons, especially when prior surgery, scarring, tumor resection, or radiotherapy, have caused a shortage of recipient vessels. Although already being a standard approach for head and neck reconstructions, we investigated whether the indication of the superior thyroid artery (STA) as a safe and universal recipient vessel could be extended for reconstruction in aforementioned regions.

METHODS

Seventeen patients received free myocutaneous vastus lateralis (MVL) muscle flaps for reconstruction of upper body defects (chest n = 11; upper back n = 6). In all cases, the STA was used for microvascular anastomosis because of a lack of standard recipient vessels. A retrospective chart review was performed and the data was screened for patients' demographics, intraoperative and perioperative details, flap survival, surgical complications, and overall long-term outcomes. Patients had a minimum follow-up of 6 months.

RESULTS

Defects resulted from infections after cardiac surgery (n = 10), infections after spinal neurosurgery (n = 2) or tumor resection (n = 5). Average defect size measured 144.6 (range, 40-286 cm2; ±67.9 cm2), with a mean size of the MVL free flaps of 266.8 (range, 160-384 cm2; ±69.5 cm2). The flap success rate was 100%, with minor complications in 4 patients. No major complications were observed in any of the patients.

CONCLUSIONS

The STA is a viable and safe alternative as a recipient vessel for reconstruction of upper body defects, especially when other vessels in proximity to the defect are deprived.

Comparison of pedicled versus free flaps for reconstruction of extensive deep sternal wound defects following cardiac surgery: A retrospective study

BACKGROUND

Myocutaneous pedicled flaps are the method of choice for sternal reconstruction after deep sternal wound infection (DSWI) following cardiac surgery. We set out to investigate whether free flaps provide a superior alternative for particularly extended sternal defects.

METHODS

Between October 2008 and February 2020, 86 patients with DSWI underwent sternal reconstruction with myocutaneous flaps at our institution. Patients were retrospectively grouped into pedicled (A; n = 42) and free flaps (B, n = 44). The objective was to compare operative details, outcome variables, surgical as well as medical complication rates between both groups, retrospectively. Binary logistic regression analysis was applied to determine the effect of increasing defect size on flap necrosis.

RESULTS

Rates of partial flap necrosis (>5% of the skin island) were significant higher in pedicled flaps (n = 14), when compared to free flaps (n = 4) (OR: 5.0; 33 vs. 9%; p = .008). Increasing defect size was a significant risk factor for the incidence of partial flap necrosis of pedicled flaps (p = .012), resulting in a significant higher rate of additional surgeries (p = .036). Binary regression model revealed that the relative likelihood of pedicled flap necrosis increased by 2.7% with every extra square-centimeter of defect size.

CONCLUSION

To avoid an increased risk of partial flap necrosis, free flaps expand the limits of extensive sternal defect reconstruction with encouragingly low complication rates and proved to be a superior alternative to pedicled flaps in selected patients.

A multivariable miRNA signature delineates the systemic hemodynamic impact of arteriovenous shunt placement in a pilot study

Arteriovenous (AV) fistulas for hemodialysis can lead to cardiac volume loading and increased serum brain natriuretic peptide (BNP) levels. Whether short-term AV loop placement in patients undergoing microsurgery has an impact on cardiac biomarkers and circulating microRNAs (miRNAs), potentially indicating an increased hemodynamic risk, remains elusive. Fifteen patients underwent AV loop placement with delayed free flap anastomosis for microsurgical reconstructions of lower extremity soft-tissue defects. N-terminal pro-BNP (NT-proBNP), copeptin (CT-proAVP), and miRNA expression profiles were determined in the peripheral blood before and after AV loop placement. MiRNA expression in the blood was correlated with miRNA expression from AV loop vascular tissue. Serum NT-proBNP and copeptin levels exceeded the upper reference limit after AV loop placement, with an especially strong NT-proBNP increase in patients with preexistent cardiac diseases. A miRNA signature of 4 up-regulated (miR-3198, miR-3127-5p, miR-1305, miR-1288-3p) and 2 down-regulated miRNAs (miR30a-5p, miR-145-5p) which are related to cardiovascular physiology, showed a significant systemic deregulation in blood and venous tissue after AV loop placement. AV loop placement causes serum elevations of NT-proBNP, copeptin as well as specific circulating miRNAs, indicating a potentially increased hemodynamic risk for patients with cardiovascular comorbidities, if free flap anastomosis is delayed.

One-stage double free flap arteriovenous loop reconstruction of a massive abdominothoracic defect following necrotizing fasciitis: A case report

We report the case of a 67-year old male with necrotizing fasciitis after injection of the glenohumeral joint. After extensive debridement a massive defect from the left hip joint to the left upper arm, exposing ribs, scapula, axillary vessels and brachial plexus (45 × 40 cm) was present. Reconstruction was performed with a conjoined right myocutaneous tensor fasciae lata/vastus lateralis flap and a left myocutaneous vastus lateralis flap in combination with an arteriovenous loop originating from the axillary vessels using the greater saphenous vein. Revisional surgeries were necessary including ribs resection and flap re-advancements. Due to multiorganic failure invasive ventilation, renal replacement- and extensive transfusion therapy was required. After 241 days the patient was discharged for rehabilitation. At the 12 months follow-up wounds were sufficiently closed without the need for further intervention. This case illustrates that immediate diagnosis followed by an aggressive multidisciplinary treatment approach is crucial for the patient survival.

THE DESIGN OF THE ARTERIOVENOUS VASCULAR LOOP DOES NOT AFFECT ITS PATENCY: EXPERIMENTAL STUDY

OBJECTIVE

To evaluate the effect of the design of a femoral vascular loop with anastomosis in the femoral artery of rabbits on the presence of flow (patency) after seven days.

METHODS

A total of 39 rabbits underwent arteriovenous microanastomosis using the microsurgical technique. Two loop designs were used: one circular and the other angled. The parameters evaluated were presence or absence of flow, signs of hemolysis and hemodynamic changes.

RESULTS

After seven days, flow was present in 68% of the angled loops and 75% of the circular loops (p > 0.05). There was a significant intragroup decrease in pCO₂ and a significant increase in pH. For the other parameters evaluated, no significant differences between the two loop models were found.

CONCLUSIONS

A reproducible vascular loop model was shown. There was no significant difference between the two vascular loop models about the presence of flow after seven days. Level of Evidence V, Animal experimental study.

One-Stage versus Two-Stage Arteriovenous Loop Reconstructions: An Experience on 103 Cases from a Single Center

BACKGROUND

The optimal time for flap anastomosis to an arteriovenous loop remains controversial. Whether perforator flaps and axially vascularized muscle or fasciocutaneous flaps lead to comparable outcomes in conjunction with arteriovenous loops has not been investigated.

METHODS

Medical records from 103 patients undergoing arteriovenous loop reconstruction (76 one-stage and 27 two-stage) between 2007 and 2017 were reviewed. Postoperative outcomes were compared between one- and two-stage arteriovenous loop reconstructions and different types of free flaps.

RESULTS

Rates of flap thrombosis, major wound complications, and flap failure did not differ significantly between one- and two-stage arteriovenous loop reconstructions (14.47 percent versus 11.11 percent, p = 1.00; 30.26 percent versus 25.93 percent, p = 0.67; and 10.53 percent versus 7.41 percent, p = 1.00). For two-stage arteriovenous loop reconstructions, the time interval between arteriovenous loop placement and flap anastomosis was a predictor for thrombotic events (OR, 1.31; p < 0.05). Anterolateral thigh flaps in conjunction with arteriovenous loops showed higher failure rates (33.33 percent) compared with all other flaps (6.59 percent) (p < 0.05) and combined latissimus dorsi and parascapular flaps (0 percent) (p < 0.05). Thrombosis rates were higher in anterolateral thigh flaps (33.33 percent) compared with all other flaps (10.99 percent; p = 0.056), and combined latissimus dorsi and parascapular flaps (0 percent; p < 0.05).

CONCLUSIONS

Two-stage arteriovenous loop reconstructions do not lead to increased postoperative complications compared to one-stage arteriovenous loop reconstructions and may be favorable in complicated cases because of shorter operative times. To avoid an increased thrombosis risk, flap anastomosis should not be delayed beyond 10 days in two-stage arteriovenous loop reconstructions. Anterolateral thigh flaps are less suitable for arteriovenous loop reconstructions because of higher complication rates.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

Experimental study of histological changes in vascular loops according to the duration of the postoperative period: Application in reconstructive microsurgery

OBJECTIVES

To analyze the histological changes observed in venous grafts subjected to arterial blood flow as a function of the duration of the postoperative period to optimize their use in free flap reconstructions.

METHOD

Twenty-five rats (7 females and 18 males) underwent surgery. Surgeries were performed on one animal per week. Five weeks after the first surgery, the same five animals were subjected to an additional surgery to assess the presence or absence of blood flow through the vascular loop, and samples were collected for histological analysis. This cycle was performed five times.

RESULTS

Of the rats euthanized four to five weeks after the first surgery, no blood flow was observed through the graft in 80% of the cases. In the group euthanized three weeks after the first surgery, no blood flow was observed in 20% of the cases. In the groups euthanized one to two weeks after the first surgery, blood flow through the vascular loop was observed in all animals. Moreover, intimal proliferation tended to increase with the duration of the postoperative period. Two weeks after surgery, intimal proliferation increased slightly, whereas strong intimal proliferation was observed in all rats evaluated five weeks after surgery.

CONCLUSION

Intimal proliferation was the most significant change noted in venous grafts as a function of the duration of the postoperative period and was directly correlated with graft occlusion. In cases in which vascular loops are required during free flap reconstruction, both procedures should preferably be performed during the same surgery.

Retrospective cohort study of combined approach for trunk reconstruction using arteriovenous loops and free flaps

Defect reconstruction of the trunk can be performed using microsurgical free flap transplantation. In cases of missing or inappropriate recipient vessels, microsurgical defect reconstruction of the trunk can be achieved by combining free flaps with arteriovenous loops. Here we present our 5-year experience of trunk reconstruction using AV loops and free flaps in a retrospective evaluation. We analyzed 32 cases of trunk reconstruction using a combined approach of free flap transplantation and arteriovenous loops between 2011 and 2016 regarding postoperative complications and perioperative course. Twenty-one patients suffered from sternal defects, 4 from presacral defects, 3 patients presented with lateral chest wall defects, 2 patients suffered from lumbosacral defects, 1 patient had a gluteal defect and 1 patient a defect at the clavicle. In all cases, free flap transplantation and arteriovenous loop creation were performed in a two-stage procedure. There were 8 thromboses of the arteriovenous loops with 4 flap failures. Only 1 flap loss was located in the sternal region, whereas one presacral flap and both lumbosacral flaps were lost. Reconstruction of large soft tissue defects of the trunk by a combined approach with an arteriovenous loop creation and consecutive free flap transplantation represents a reliable procedure in ventral and posterior cranial localization, whereas in the caudal posterior region, AV loop thrombosis can occur. Therefore, to minimize flap loss, a two-stage procedure should be performed.

Classification of chronic radiation-induced ulcers in the chest wall after surgery in breast cancers

BACKGROUND AND PURPOSE

To explore the methods of clinical classification in chronic radiation-induced ulcers in the chest wall (CRUCWs).

MATERIALS AND METHODS

A total of 64 patients with CRUCWs were treated. We divided the cases into 3 types (mild, moderate, or severe) according to their clinical manifestations. Conservative treatments, axial-pattern myocutaneous or local flaps, or filleted flaps were applied correspondingly.

RESULTS

The cases were divided as follows: mild (n = 11), moderate (n = 45), and severe (n = 8). Eight cases were cured by conservative surgical therapy. One case had a recurrence 6 months after conservative therapy and was cured by a latissimus dorsi myocutaneous flap. The transferred flaps all survived, including 26 transverse rectus abdominis myocutaneous flaps, 8 longitudinal rectus abdominis myocutaneous flaps, 6 latissimus dorsi myocutaneous flaps, 3 contralateral breast flaps, 5 lateral thoracic rotation flaps, and 7 filleted flaps. In 2 transverse rectus abdominis myocutaneous flaps and 2 latissimus dorsi myocutaneous flaps, distal necrosis appeared in small areas. The resulting wounds were salvaged with skin graft and full healing was achieved.

CONCLUSION

CRUCWs can be divided into three types. Surgical methods should vary with distinguished classifications. The effective classification of CRUCWs has definite instructive significance on the selection of surgical approaches.

Important Developments in Burn Care

LEARNING OBJECTIVES

After studying this article, the participant should be able to: 1. Explain the epidemiology of severe burn injury in the context of socioeconomic status, gender, age, and burn cause. 2. Describe challenges with burn depth evaluation and novel methods of adjunctive assessment. 3. Summarize the survival and functional outcomes of severe burn injury. 4. State strategies of fluid resuscitation, endpoints to guide fluid titration, and sequelae of overresuscitation. 5. Recognize preventative measures of sepsis. 6. Explain intraoperative strategies to improve patient outcomes, including hemostasis, restrictive transfusion, temperature regulation, skin substitutes, and Meek skin grafting. 7. Translate updates in the pathophysiology of hypertrophic scarring into novel methods of clinical management. 8. Discuss the potential role of free tissue transfer in primary and secondary burn reconstruction.

SUMMARY

Management of burn-injured patients is a challenging and unique field for plastic surgeons. Significant advances over the past decade have occurred in resuscitation, burn wound management, sepsis, and reconstruction that have improved outcomes and quality of life after thermal injury. However, as patients with larger burns are resuscitated, an increased risk of nosocomial infections, sepsis, compartment syndromes, and venous thromboembolic phenomena have required adjustments in care to maintain quality of life after injury. This article outlines a number of recent developments in burn care that illustrate the evolution of the field to assist plastic surgeons involved in burn care.

Thoracic Wall Reconstruction after Tumor Resection

Introduction

Surgical treatment of malignant thoracic wall tumors represents a formidable challenge. In particular, locally advanced tumors that have already infiltrated critical anatomic structures are associated with a high surgical morbidity and can result in full-thickness defects of the thoracic wall. Plastic surgery can reduce this surgical morbidity by reconstructing the thoracic wall through various tissue transfer techniques. Sufficient soft-tissue reconstruction of the thoracic wall improves quality of life and mitigates functional impairment after extensive resection. The aim of this article is to illustrate the various plastic surgery treatment options in the multimodal therapy of patients with malignant thoracic wall tumors.

Materials and methods

This article is based on a review of the current literature and the evaluation of a patient database.

Results

Several plastic surgical treatment options can be implemented in the curative and palliative therapy of patients with malignant solid tumors of the chest wall. Large soft-tissue defects after tumor resection can be covered by local, pedicled, or free flaps. In cases of large full-thickness defects, flaps can be combined with polypropylene mesh to improve chest wall stability and to maintain pulmonary function. The success of modern medicine has resulted in an increasing number of patients with prolonged survival suffering from locally advanced tumors that can be painful, malodorous, or prone to bleeding. Resection of these tumors followed by thoracic wall reconstruction with viable tissue can substantially enhance the quality of life of these patients.

Discussion

In curative treatment regimens, chest wall reconstruction enables complete resection of locally advanced tumors and subsequent adjuvant radiotherapy. In palliative disease treatment, plastic surgical techniques of thoracic wall reconstruction provide palliation of tumor-associated morbidity and can therefore improve patients’ quality of life.

Combined free flaps with arteriovenous loops for reconstruction of extensive thoracic defects after sternal osteomyelitis

BACKGROUND

Various local flaps have been described for patients suffering from sternal osteomyelitis and are regarded as a standard procedure for defect reconstruction. In contrast, the use of microsurgical free flaps has been reported anecdotally only. We present our experiences with the combination of an arteriovenous loop and a free flap transfer in defects larger than half of the sternum.

METHODS

Between January 2012 and October 2014, eight patients with a mean age of 68 years who suffered from extensive deep sternal osteomyelitis were operated in a consecutive series. After radical surgical debridement, the defect size comprised all three thirds of the sternum. Defect reconstruction was achieved by means of free flap transplantation using the vastus lateralis myocutaneous flap, rectus abdominis, and bipedicled latissimus dorsi/parascapular flap. As local recipient vessels were depleted in all patients, the pedicle of the flap was anastomosed to a high-flow and short-length subclavian arteriovenous loop as recipient vessel in all cases.

RESULTS

The immediate postoperative course in all patients was uneventful despite one axonal injury to the femoral nerve at the donor site. There was no partial or total flap loss. During a mean follow-up of 9 months, one patient suffered from a local infection at the donor site. In all patients, a successful defect reconstruction could be achieved.

CONCLUSION

Depletion of local recipient vessels as an obstacle for free flap reconstruction can be overcome by creating an arteriovenous loop. Even extensive defects are adequate for defect reconstruction using a single or, in extreme cases, bipedicled free flap.