Blood Flow In Flaps Research Articles

Effect of dexmedetomidine combined with ropivacaine block on flap blood flow and patient satisfaction after flap transfer for hand trauma: a randomized controlled trial.

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Study on changes in serum irisin level in free-flap transplantation and the correlation of serum irisin level with flap blood flow

Background and aimsThe beneficial effect of myokine irisin on ischemia-reperfusion of skin flaps has been rarely reported in clinical studies. This study was designed to determine whether irisin plays a protective role in flap transplantation and identify the factors affecting serum irisin levels. Materials and methodsWe analyzed the changes in serum irisin levels and flap blood flow before and after surgery in 40 patients who underwent skin-flap transplantation. Factors affecting serum irisin levels were analyzed by metabolic parameter measurements. ResultsPreoperative serum irisin levels were positively correlated with blood flow in the skin flap 7 days post-surgery. The increase in serum irisin levels in the first 3 days after surgery positively correlated with flap blood flow. A longer duration of high-intensity exercise, higher skeletal muscle content, lower body mass index, and waist-to-hip ratio were associated with higher irisin levels. Fasting blood glucose and glycosylated hemoglobin levels showed significant negative correlations with serum irisin levels. Several other indicators, including sex, were not associated with serum irisin levels. ConclusionsSerum irisin levels benefit blood flow recovery during flap transplantation. Better outcomes may be achieved by adjusting the timing and intensity of the exercise and controlling the patient's body size.

Prompt, Objective, and Accurate Measurement of Rat Abdominal Flap Blood Flow Using Laser Speckle Flowgraphy.

The indications for free flap procedures have expanded, with recent technical advances enhancing procedural safety. However, few objective indicators exist to monitor flap status during and after the operation. This experimental study assessed laser speckle flowgraphy (LSFG) as a prompt and accurate indicator of free flap blood flow. After elevating bilateral lower abdomen flaps with superficial inferior epigastric artery (SIEA) and superficial inferior epigastric vein vasculature in Wistar rats, the right flap with the SIEA was cut (ischemic group) or the superficial inferior epigastric vein was cut (congestive group), and the unaltered left flaps were monitored using LSFG every 5 minutes for a 30-minute period. Flap survival or necrosis was assessed after 7 days. In the ischemic group, LSFG measurements were significantly lower after cutting the SIEA than beforehand (74% at 5 minutes and 72% at 30 minutes). Similar findings were seen in the congestive group (63% at 5 minutes and 55% at 30 minutes). LSFG measurements were significantly lower in the congestive group than in the ischemic group. Seven days afterward, whereas all right-side flaps with cut vessels were necrotic, all unaltered left-side flaps had survived. Our preliminary results demonstrated that LSFG could objectively identify abnormal blood flow in skin flaps as early as 5 minutes into surgery and predict graft survival. LSFG may potentially enable quick and objective assessment of flap blood flow and reduce the risk of complications and flap loss.

NIRO200NX: Reliable Monitoring System for Buried Deep Inferior Epigastric Perforator Flap.

The deep inferior epigastric perforator (DIEP) flap is a useful tool for breast reconstruction and tends to be transferred into the breast envelope as the buried flap from an aesthetic point of view. However, it is difficult to monitor the blood flow in the buried DIEP flap after reconstructive microsurgery. Near-infrared spectroscopy devices have recently been used for monitoring the blood flow of various organs. NIRO200NX (Hamamatsu Photonics) continuously measures the tissue oxygen index (TOI) and quickly reflects changes in flap blood flow. In this study, we investigated whether and how much the NIRO200NX applies to monitoring the blood flow of the buried flap. We included 156 patients who underwent breast reconstruction using a DIEP flap from October 2013 to May 2022, comprising 57 exposed and 99 buried-type DIEP flap cases. We measured TOI using NIRO200NX, in combination with conventional evaluation methods, including color check, pinprick test, and Doppler sound. A criterion of TOI 50 gave the best evaluations. All the 57 exposed-type flap cases showed no false evaluations, and NIRO200NX performed precise judgment. In 99 buried-type flap cases, NIRO200NX correctly evaluated 96 cases. For those buried-type cases, we found only two false-positive and one false-negative case. The misjudgments by NIRO200NX were likely caused by hematoma. We propose NIRO200NX as a reliable device for monitoring the blood flow of the DIEP flap and predicting the outcomes of breast reconstruction by the DIEP flap transfer.

The effect of low-intensity electromagnetic radiation of the EHF band and ozone therapy on the state of tissue blood flow in the skin flap

The effect of low-intensity electromagnetic radiation of the EHF band and ozone therapy on the state of tissue blood flow in the skin flap

Does the Anastomosis Recipient Vessel Have an Influence on Free Flap Perfusion in Microvascular Head and Neck Reconstruction-A Retrospective Analysis of 338 Cases with Comparison of Flap Perfusion between Different Arterial and Venous Recipient Vessels in Radial Free Forearm Flaps, Anterolateral Thigh Flaps, and Fibula Free Flaps.

Background: Flap perfusion is a prerequisite for microvascular free flap survival and a parameter routinely used for flap monitoring. The aim of this study was to investigate the influence of the anastomosis recipient vessel on flap perfusion. Methods: Flap perfusion was retrospectively analyzed in 338 patients who underwent head and neck reconstruction with microvascular free flaps between 2011 and 2020. The Oxygen-to-see tissue oxygen analysis system measurements for intraoperative and postoperative flap blood flow, hemoglobin concentration, and hemoglobin oxygen saturation at 8 and 2 mm tissue depths were compared between arterial anastomosis recipient vessels (external carotid artery [ECA], facial artery [FAA], lingual artery [LIA], and superior thyroid artery [STA]) and venous anastomosis recipient vessels (internal jugular vein [IJV], combination of IJV and IJV branches, IJV branches, and external jugular vein). Results: The postoperative hemoglobin concentration at 2 mm tissue depth differed significantly between arterial anastomosis recipient vessels (ECA, 41.0 arbitrary units [AU]; FAA, 59.0 AU; LIA, 51.5 AU; STA, 59.0 AU; p = 0.029). This difference did not persist in the multivariable testing (p = 0.342). No other differences in flap blood flow, hemoglobin concentration, or hemoglobin oxygen saturation were observed between the arterial and venous anastomosis recipient vessels (p > 0.05 for all). Conclusions: The arterial and venous recipient vessels used for anastomosis did not influence microvascular free flap perfusion. This underlines the capability of the studied recipient vessels to adequately perfuse free flaps, may explain the observed indifferent flap survival rates between commonly used anastomosis recipient vessels, and implies that the recipient vessel is not a confounding variable for flap monitoring with the Oxygen-to-see tissue oxygen analysis system. Further prospective studies are needed to confirm the findings.

Comparative Study of Small Vessel (under 0.8 mm) Anastomosed Free Flap and Larger Vessel (over 0.8 mm) Anastomosed Free Flap: Does Supermicrosurgery Provide Sufficient Blood Flow to the Free Flap?

This study aimed to quantify the blood flow of free flaps and compare the blood flow of small vessel (<0.8 mm) and larger vessel (>0.8 mm) anastomosed free flaps. This retrospective study included patients treated successfully with a perforator free flap in the lower extremity between June 2015 and March 2017. A color duplex ultrasound system measured the flow volume through the pedicle by analyzing the mean flow peak velocity, flow volume, and flow volume per 100 g of the flap. A total of 69 patients were enrolled in this study. There was no statistical difference in peak velocity between the small vessel anastomosed free flap (25.2 ± 5.6) and larger vessel anastomosed free flap (26.5 ± 5.4). Flow volume (6.8 ± 4.2 vs. 6.3 ± 3.6) and flow volume/100 g (3.6 ± 3.9 vs. 6.2 ± 6.9) also did not show significant differences. Small vessel (<0.8 mm) free flaps showed similar flow velocity and flow volume to larger vessel (>0.8 mm) anastomosed free flaps. Blood flow to the small vessel anastomosed free flap was sufficient despite its small vessel size.

Free Flap Perfusion in Microvascular Head and Neck Reconstruction: Influence of the Number of Ischemia Intervals and Ischemia Duration-A Retrospective Study.

In microvascular head and neck reconstruction, ischemia of the free flap tissue is inevitable during microsurgical anastomosis and may affect microvascular free flap perfusion, which is a prerequisite for flap viability and a parameter commonly used for flap monitoring. The aim of this study was to investigate the influence of the number of ischemia intervals and ischemia duration on flap perfusion. Intraoperative and postoperative flap blood flow, hemoglobin concentration, and hemoglobin oxygen saturation at 2 and 8 mm tissue depths, as measured with the O2C tissue oxygen analysis system, were retrospectively analyzed for 330 patients who underwent microvascular head and neck reconstruction between 2011 and 2020. Perfusion values were compared between patients without (control patients) and with a second ischemia interval (early or late) and examined with regard to ischemia duration. Intraoperative and postoperative flap blood flow at 8 mm tissue depth were lower in patients with early second ischemia intervals than in control patients [102.0 arbitrary units (AU) vs 122.0 AU, P = .030; 107.0 AU vs 128.0 AU, P = .023]. Both differences persisted in multivariable analysis. Intraoperative and postoperative flap blood flow at 8 mm tissue depth correlated weakly negatively with ischemia duration in control patients (r = -.145, P = .020; r = -.124, P = .048). Both associations did not persist in multivariable analysis. The observed decrease in microvascular flap blood flow after early second ischemia intervals may reflect ischemia-related vascular flap tissue damage and should be considered as a confounding variable in flap perfusion monitoring.

L-Borneol promotes skin flap survival by regulating HIF-1α/NF-κB pathway

Ethnopharmacological relevanceThe clinical application of skin flaps in surgical reconstruction is frequently impeded by the occurrence of distant necrosis. L-Borneol exhibits myogenic properties in traditional Chinese medicine and is used in clinical settings to promote wound healing and conditions such as stroke. Nevertheless, the precise mechanism by which borneol exerts its protective effects on skin flap survival remains unclear. Aim of the studyTo explore the potential of L-borneol to promote skin flap survival and elucidate the underlying mechanisms. Materials and methodsThirty-six male Sprague–Dawley rats were randomly divided into three groups: a high-dose (200 mg/kg L-borneol per day), a low-dose (50 mg/kg/day), and control group (same volume of solvent). In each rat, a modified rectangular McFarlane flap model measuring 3 × 9 cm was constructed. Daily intragastric administration of L-borneol or solvent was performed. The flap was divided into three square sections of equal size, namely Zone I (the proximal zone), Zone II (the intermediate zone), and Zone III (the distal zone). The survival rate was quantified, and the histological state of each flap was evaluated on the seventh day following the surgical procedure. The assessment of angiogenesis was conducted using lead oxide/gelatin angiography, whereas the evaluation of blood flow in the free flap was performed using laser Doppler flow imaging. Superoxide dismutase activity was detected using the water-soluble tetrazolium salt-8 method. The quantities of vascular endothelial growth factor, interleukin (IL)-1β, IL-6, and tumour necrosis factor-α were determined using immunohistochemistry. The levels of nuclear transcription factor-κB, hypoxia-inducible factor-1, B-cell lymphoma-2 (BCL-2), and BCL-2-associated X (BAX) were determined by Western blotting technique. ResultsFlap survival rate significantly improved and neutrophil recruitment and release were enhanced after treatment with the compound. Angiogenesis was promoted. L-borneol protected against oxidative stress by increasing superoxide dismutase activity and decreasing malondialdehyde content. It downregulated the hypoxia-inducible factor nuclear transcription factor-κB pathway, leading to the inhibition of several inflammatory factors. Simultaneously, it facilitated the expression of vascular endothelial growth factor and BCL-2. ConclusionThe study shows that L-borneol may promote skin flap survival by inhibiting HIF-1α/NF-κB pathway.

Attached compared with unattached surface probes for monitoring flap perfusion in microvascular head and neck reconstruction: a feasibility study

Unattached surface probes are commonly used with the O2C analysis system (LEA Medizintechnik, Germany) to monitor microvascular free flap perfusion. This study compared attached and unattached surface probes for extraoral free flaps. The study included 34 patients who underwent extraoral microvascular head and neck reconstruction between 2020 and 2022. Flap perfusion was monitored postoperatively using the O2C analysis system at 0, 12, 24, 36, and 48 h, with an attached surface probe at 3 mm tissue depth and an unattached surface probe at 2 mm and 8 mm tissue depths. Clinical complications, technical errors, and perfusion measurement values were compared. No clinical complications (attachment suture infections) or technical errors (probe detachment) occurred. Flap blood flow values of the probes were partially different (3 mm vs. 2 and 8 mm: p < 0.001; p = 0.308) and moderately correlated (3 mm with 2 and 8 mm: r = 0.670, p < 0.001; r = 0.638, p < 0.001). Hemoglobin concentration and oxygen saturation values were generally different (3 mm vs. 2 and 8 mm: all p < 0.001) and variably correlated (3 mm with 2 and 8 mm: r = 0.756, r = 0.645; r = 0.633, r = 0.307; all p < 0.001). Both probes are comparable in terms of technical feasibility and patient safety, with flap perfusion values dependent on tissue measurement depth.

Flap perfusion monitoring with an attached surface probe in microvascular reconstruction of the oral cavity

ObjectivesPostoperative flap monitoring is essential in oral microvascular reconstruction for timely detection of vascular compromise. This study investigated the use of attached surface probes for the oxygen-2-see (O2C) analysis system (LEA Medizintechnik, Germany) for intraoral flap perfusion monitoring.Materials and methodsThe study included 30 patients who underwent oral reconstruction with a microvascular radial-free forearm flap (RFFF) or anterolateral thigh flap (ALTF) between 2020 and 2022. Flap perfusion was measured with attached (3-mm measurement depth) and unattached surface probes (2- and 8-mm measurement depths) for the O2C analysis system at 0, 12, 24, 36, and 48 h postoperatively. Flap perfusion monitoring with attached surface probes was evaluated for cut-off values for flap blood flow, hemoglobin concentration, and hemoglobin oxygen saturation indicative of vascular compromise and for accuracy and concordance with unattached surface probes.ResultsThree RFFFs were successfully revised, and one ALTF was unsuccessfully revised. The cut-off values indicative of vascular compromise for flap perfusion monitoring with attached surface probes were for RFFF and ALTF: blood flow < 60 arbitrary units (AU) and < 40AU, hemoglobin concentration > 100AU and > 80AU (both > 10% increase), and hemoglobin oxygen saturation < 40% and < 30%. Flap perfusion monitoring with attached surface probes yielded a 97.1% accuracy and a Cohen’s kappa of 0.653 (p < 0.001).ConclusionsFlap perfusion monitoring with attached surface probes for the O2C analysis system detected vascular compromise accurately and concordantly with unattached surface probes.Clinical relevanceAttached surface probes for the O2C analysis system are a feasible option for intraoral flap perfusion monitoring.

A method to isolate human dermal microvascular pericytes without the use of magnetic beads sorting in vitro

Human dermal microvascular pericytes (HDMPCs) are a critical component of the skin flap microvasculature and play a role in regulating flap blood flow and integrity. Pericytes were isolated mostly via magnetic bead sorting in the published literature. In this study, we discuss in detail how to separate and concentrate pericytes from human facial flaps using enzyme digestion and differential adherence instead of magnetic bead sorting. Cultured HDMPCs were seen to have well-spread irregular edges, with most cells having two longitudinal pericytic processes. The phalloidin staining revealed that HDMPCs had prominent stress fibers, and the nucleus deviated to the side that interacted with the neighboring pericytic processes. Flow cytometry analysis showed that the positive rates of NG2 in the first and second passages were 91.2% ± 0.7% and 98.2% ± 0.1% separately. And the immunofluorescence and western blot results demonstrated a positive expression of α smooth muscle actin (αSMA), platelet-derived growth factor receptor β (PDGFRβ), and NG-2, while the endothelial cell marker CD31 was negatively expressed. In summary, we established a straightforward methodology for selectively isolating and identifying HDMPCs as well as generating high-purity cell cultures in vitro without the use of magnetic bead sorting.

Latissimus dorsi musculocutaneous flap grafting to the infected recipient site in a patient with irradiated locally advanced breast cancer and multiple lung metastases

BackgroundMusculocutaneous (MC) flaps are more resistant to infection than implants, but no clinical results have been reported so far about the grafting of MC flap to the overtly infected sites.Case presentationA 66-year-old woman had received radiotherapy, a total dose of 50 Gy, to her large mucinous breast cancer to control bleeding from the tumor and was referred to our hospital for further treatment. On her first visit to our hospital, her left breast showed radiation-induced total necrosis with Pseudomonasaeruginosa infection. Removal of the necrotic breast tissue resulted in direct exposure of the left ribs and intercostal muscles with intractable chest pain requiring analgesics. The presence of concomitant life-threatening multiple lung metastases made us change the treatment from letrozole and palbociclib to bevacizumab and paclitaxel, leading to marked regression of the lung metastases. To alleviate her chest pain and get local wound healing, we treated the patient with latissimus dorsi (LD)-MC flap grafting to the exposed chest wall after four months of taxane-containing chemotherapy. The patient has got marked pain relief immediately after the operation. Skin island of the grafted LD-MC flap showed no problems for 4 days just after the operation but gradually turned out to be edematous to ill-colored in the distal part of the skin island. Post-operative clinical outcome suggested that Pseudomonasaeruginosa infection might have had some adverse effect, e.g., microemboli, on MC flap blood flow. Partial necrosis of the LD-MC flap made the patient receive conservative wound management for a very long period of 11 months, finally leading to complete wound healing. After palliative surgery, the patient has been receiving fulvestrant and palbociclib for 14 months and doing well with good control of multiple lung metastases.ConclusionsBreast surgical oncologists should note that partial flap necrosis can occur when a LD-MC flap is grafted to the infected recipient site and consider the anti-coagulant therapy just after the operation to avoid the adverse effects of the infection.

Norepinephrine preserved flap blood flow compared to phenylephrine in free transverse rectus abdominis myocutaneous flap breast reconstruction surgery: A randomized pilot study

Vasopressors are used in up to 85% of cases during free flap surgery. However, their use is still debated with concerns of vasoconstriction-related complications, with rates up to 53% in minor cases. We investigated the effects of vasopressors on flap blood flow during free flap breast reconstruction surgery. We hypothesized that norepinephrine may preserve flap perfusion better than phenylephrine during free flap transfer. A randomized pilot study was performed in patients undergoing free transverse rectus abdominis myocutaneous (TRAM) flap breast reconstruction. Patients with peripheral artery disease, allergies to study drugs, previous abdominal operations, left ventricular dysfunction, or uncontrolled arrhythmias were excluded. Twenty patients were randomized to receive either norepinephrine (0.03-0.10µg/kg/min) or phenylephrine (0.42-1.25µg/kg/min) (each n=10) to maintain a mean arterial pressure of 65-80mmHg. The primary outcome was differences in mean blood flow (MBF) and pulsatility index (PI) of flap vessels after anastomosis measured using transit time flowmetry in the two groups. Secondary outcomes included flap loss, necrosis, thrombosis, wound infection, and reoperation within 7 days postoperatively. After anastomosis, MBF showed no significant change in the norepinephrine group (mean difference, -9.4±14.2mL/min; p=0.082), whereas it was reduced in the phenylephrine group (-7.9±8.2mL/min; p=0.021). PI did not change in either group (0.4±1.0 and 1.3±3.1 in the norepinephrine and phenylephrine groups; p=0.285 and 0.252, respectively). There were no differences in secondary outcomes between the groups. During free TRAM flap breast reconstruction, norepinephrine seems to preserve flap perfusion compared to phenylephrine. However, further validation studies are required.

Impacts of vascular comorbidities on free flap perfusion in microvascular head and neck reconstruction

PurposeArterial hypertension (AHTN), type 2 diabetes mellitus (DM), and atherosclerotic vascular disease (ASVD) are common vascular comorbidities in patients undergoing reconstruction of the head and neck region with a microvascular free flap. These conditions may affect flap perfusion (microvascular blood flow and tissue oxygenation), which is a prerequisite for flap survival and thus reconstruction success. This study aimed to investigate the impacts of AHTN, DM, and ASVD on flap perfusion.MethodsData from 308 patients who underwent successful reconstruction of the head and neck region with radial free forearm flaps, anterolateral thigh flaps, or fibula free flaps between 2011 and 2020 were retrospectively analyzed. Flap perfusion was measured intraoperatively and postoperatively with the O2C tissue oxygen analysis system. Flap blood flow, hemoglobin concentration, and hemoglobin oxygen saturation were compared between patients with and without AHTN, DM, and ASVD.ResultsIntraoperative hemoglobin oxygen saturation and postoperative blood flow were lower in patients with ASVD than in patients without ASVD (63.3% vs. 69.5%, p = 0.046; 67.5 arbitrary units [AU] vs. 85.0 AU, p = 0.036; respectively). These differences did not persist in the multivariable analysis (all p > 0.05). No difference was found in intraoperative or postoperative blood flow or hemoglobin oxygen saturation between patients with and without AHTN or DM (all p > 0.05).ConclusionPerfusion of microvascular free flaps used for head and neck reconstruction is not impaired in patients with AHTN, DM, or ASVD. Unrestricted flap perfusion may contribute to the observed successful use of microvascular free flaps in patients with these comorbidities.

Cross‐finger flap as ultima ratio for the reconstruction of defects of the finger flexor sides

Cross‐finger flap as ultima ratio for the reconstruction of defects of the finger flexor sides

Renaissance of prepectoral implant-based breast reconstruction: theoretical basis and research status

To overview the theoretical basis and research status of prepectoral implant-based breast reconstruction. The domestic and foreign researches on the application of prepectoral implant-based breast reconstruction in breast reconstruction were retrospectively analyzed. The theoretical basis, clinical advantages, and limitations of this technique were summarized and the future development trend in this field was discussed. The recent advances in breast cancer oncology, the development of materials and the concept of oncology reconstruction have provided a theoretical basis for prepectoral implant-based breast reconstruction. The selection of patients and the experience of surgeons are crucial for postoperative outcomes. Ideal thickness and blood flow of flaps are the most important considerations for the selection of prepectoral implant-based breast reconstruction. However, its long-term reconstruction outcomes and clinical benefits and risks in Asian populations still need to be confirmed by more studies. Prepectoral implant-based breast reconstruction has a broad application prospect in breast reconstruction following mastectomy. However, the evidence is limited at present. Randomized study with long-term follow-up is urgently in need to provide sufficient evidence to evaluate the safety and reliability of prepectoral implant-based breast reconstruction.

An analytical model for sensing microvascular blood flow in flaps and organ grafts

Thrombosis after free flap transfer or solid organ allotransplantation surgeries can lead to flap or organ failure requiring re-transplantation and sometimes leading to death. Current technologies can provide early warnings of thrombosis, but the resulting measurements can be influenced by motions associated with route operations in patient care and by subtle aspects associated with the use of the devices. These systems also require wired interfaces to external data acquisition hardware, which limits patient mobility and subject the sensor to artefact from interface disruption attributable to external tension. Furthermore, many existing systems require that the probe be mounted directly on the anastomosed artery or vein which puts these delicate structures at risk for kinking, avulsion, or other disruption. Recent reports describe a wireless, implantable flow sensing probe technology that exploits thermal transport mechanisms to enable continuous monitoring of microvascular flow velocity within peripheral tissue that is remote from the critical blood supply. The capability is useful for the reliable detection of thrombosis in auto- or allotransplanted flaps or organs. Because the probe directly measures temperature rather than flow velocity, analytical models must be used to interpret the results. Here, such a model, accounting for both heat conduction and heat convection (due to blood flow), is developed to determine the blood flow velocity in flaps and organ grafts for this flow sensing probe. The model is validated by in vitro experiments without and with blood flow and further applied to in vivo experiments to predict the flow velocity. The model serves as an important support for this type of flow sensing probe and ensures reliable and accurate flow monitoring after the transplantation operations.

Perfusion of microvascular free flaps in head and neck reconstruction after prior neck dissection and irradiation

Microvascular free flaps are frequently used for head and neck reconstruction after prior neck dissection (ND) and neck irradiation (RTX). The aim of this study was to investigate the influence of ND and RTX on flap perfusion as a critical factor for flap success. Overall, 392 patients reconstructed with a microvascular fasciocutaneous flap (FF) or perforator flap (PF) in the head and neck region between 2011 and 2020 were analysed retrospectively. Flap perfusion measured intraoperatively and postoperatively with the O2C tissue oxygen analysis system was compared between patients who had received neither ND nor RTX (controls), patients who had received ND but no RTX (ND group), and patients who had received both ND and RTX (ND+RTX group). Intraoperative and postoperative flap blood flow was decreased in FFs in ND group patients compared to controls (median 66.3 AU vs 86.0 AU, P = 0.023; median 73.5 AU vs 93.8 AU, P = 0.045, respectively). In the multivariable analysis, these differences showed a tendency to persist (P = 0.052 and P = 0.056). Flap success rates were similar in control patients, ND patients, and ND+RTX patients (98.7%, 94.0%, and 97.6%, respectively). Flap perfusion is not reduced in FFs and PFs in patients who have undergone ND or ND and RTX. This indicates that neck dissection and neck irradiation should not be contraindications for microvascular free flap reconstruction.

Impact of age on microvascular free flap perfusion in head and neck reconstruction

Aging is associated with structural and functional cardiovascular changes that may affect microvascular free flap perfusion, which is a prerequisite for flap viability and flap success. This study is aimed to investigate the impact of age on flap perfusion. Intraoperative and postoperative flap perfusion of 348 patients who underwent successful reconstruction with a radial free forearm flap (RFFF), anterolateral thigh flap (ALTF), or fibular free flap (FFF) was retrospectively analyzed and compared between older (>70 years) and younger patients (≤70 years) using the Mann-Whitney test and linear regression models. Intraoperative flap blood flow and hemoglobin concentration (55.5 arbitrary units [AU] vs 69.3 AU, P=.004; 42.5 AU vs 47.3 AU, P=.016, respectively) were reduced in ALTFs in older patients compared with younger patients. These 2 differences did not persist in multivariable testing (P=.097 and P=.323, respectively). No other differences were observed between the older and younger patients in terms of intraoperative and postoperative flap blood flow, hemoglobin concentration, and hemoglobin oxygen saturation in RFFFs, ALTFs, and FFFs (all P > .05). Age has no impact on microvascular free flap perfusion in RFFFs, ALTFs, and FFFs. This could contribute to the observed equal success of free flaps in older patients.