Guidelines for the optimization of microsurgery in atherosclerotic patients

Reconstruction of a septic femoral triangle fistula with a pedicled DIEP flap: A case report and mini-review

Flap-based reconstruction techniques have shown promise in preventing scar contractures and enhancing healing in fold areas by providing vascularized and thick tissue. We report a septic rupture of the superficial femoral artery treated with an arterial allograft and covered with a contralateral pedicled Deep Inferior Epigastric Artery Perforator (DIEP) flap. The patient presented favorable outcomes, including optimal healing at 8 months, with no functional limitation. A literature review also discusses alternative pedicled perforator flaps. These modern techniques present several advantages, including reliability, and can be of great interest in complex vascular surgery cases.

Ultrastructural changes of vascular smooth muscle cells and resistance to vasospasm treatment in femoral arteries of an arteriosclerotic rat model

The objective of this study was to establish an animal model of arteriosclerosis for assessing vasospasm and to investigate the relationship between arteriosclerosis and vasospasm. Twelve-week-old male Sprague-Dawley rats were fed a diet supplemented with adenine and vitamin D (adenine/vitD). Body weight, blood, and femoral artery histopathology were assessed at 2, 4, and 6 weeks. Change in the femoral artery was examined by transmission electron microscope (TEM). Vasospasm was induced by administering epinephrine extravascularly into the femoral artery and released by the treatment with lidocaine as a vasodilator. During this period, the extravascular diameter and blood flow were measured. The rats in the adenine/vitD group developed renal dysfunction, uremia, hyperphosphatemia, and elevated serum alkaline phosphatase. Histological and TEM analyses of the femoral arteries in the treated rats revealed the degeneration of elastic fibers and extensive calcification of the tunica media and intima. Vascular smooth muscles were degenerated and osteoblasts were developed, resulting in calcified arteriosclerosis. Vasospasm in arteriosclerotic arteries was detected; however, vasodilation as well as an increase in the blood flow was not observed. This study revealed the development of vasospasm in the femoral arteries of the arteriosclerotic rats and, a conventional vasodilator did not release the vasospasm.

Lower Extremity Reconstruction with Anterolateral Thigh Free-Flap Anastomoses: A Computational Fluid Dynamic Analysis

BACKGROUND

 The anterolateral thigh free flap is an option for repairing soft tissue defects of the distal lower extremity. This flap uses the descending branch of the lateral circumflex femoral (LCF) artery as the flap vessel. The recipient vessel in these flaps is often the anterior tibial (AT), posterior tibial (PT), or peroneal (P) arteries. Computational fluid dynamic (CFD) evaluation of anastomoses between these vessels can optimize outcomes.

METHODS

 Thirty-eight CFD models were created to model end-to-side (ETS) and end-to-end (ETE) anastomoses for lower extremity reconstruction. Seven out of thirty-eight models represented ETS anastomoses between the LCF and AT arteries with varying anastomotic angles. Nine out of thirty-eight models represented 45-degree ETS anastomoses between varying diameters of the LCF and AT, PT, and P arteries. Nine out of thirty-eight models represented stenosis on the flap vessel and recipient vessel, pre- and post-bifurcation. Nine out of thirty-eight models represented ETE anastomoses, rather than ETS, with varying vessel diameters. Four out of thirty-eight models represented ETE anastomoses with varying regions and levels of stenosis.

RESULTS

 Stasis of blood flow in ETS models increased as anastomotic angle increased in a logarithmic relationship (R 2 = 0.918). Flow was optimized overall as flap and recipient vessel diameters approached one another. In ETS models, flap vessel and postbifurcation recipient vessel stenosis were found to substantially increase stasis.

CONCLUSION

 Selection of flap and recipient vessels with similar diameters can optimize outcomes in microvascular anastomoses. In the context of lower extremity reconstruction with the ALT flap, the PT artery can be recommended as a first-line recipient vessel due to its similar vessel caliber to the LCF and relative ease of surgical access compared with the P artery. Avoidance of areas of stenosis is recommended to ensure laminar flow and reduce the operative difficulty associated with performing anastomoses on nonpliable arteries. Striving for increased acuity of anastomotic angles is recommended to optimize the flow in ETS microvascular anastomoses.

Revisiting Bipedicled Flaps for Lower Extremity Distal Third Defects

BACKGROUND

Lower extremity reconstruction of the distal third of the leg is challenging. Free tissue transfer is the criterion standard. The COVID-19 pandemic encouraged seeking alternatives for resource consuming procedures. Bipedicled flaps are flaps with a dual-source subdermal perfusion. The purpose of this study was to assess outcomes of patients who had bipedicled flaps primary or auxiliary local flap for distal third leg/foot reconstruction.

METHODS

A retrospective review of patients undergoing lower extremity reconstruction (2020-2021) was performed. Inclusion criteria were patients older than 18 years with lower extremity wounds secondary to traumatic injury for which bipedicled flaps were used in the reconstruction. Exclusion criteria included lower extremity wounds secondary to peripheral vascular disease or diabetes.

RESULTS

Fourteen patients were included in the study. All patients had distal third of the leg/foot wounds, and 12 patients (87.5%) had concurrent leg fractures. In 8 patients (57.1%), the bipedicled flap was used to decrease the wound size and facilitate another concurrent flap: hemisoleus (21.4%), anterior tibialis muscle turnover (14.3%), medial plantar artery (14.3%), and posterior tibial artery perforator (14.3%). Mean wound size for bipedicle flaps used alone was 42.0 ± 18.3 cm2, whereas wounds that required a bipedicled flap with an additional flap were 69.9 ± 80.8 cm2 (P = 0.187). Two patients had partial flap necrosis (14.3%) but healed their defect. One patient had nonunion (7.1%). Limb salvage rate was 100%.

CONCLUSIONS

Bipedicled flaps can be used as an alternative to free flaps in distal third leg/foot defects in select patients. If distal extremity wounds cannot be covered with a bipedicled flap alone, the flap can be used an accessory flap to facilitate reconstruction with other local flaps.

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

PURPOSE

Arterial 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.

METHODS

Data 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.

RESULTS

Intraoperative 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).

CONCLUSION

Perfusion 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.

Microsurgical Breast Reconstruction in Patients with Disorders of Hemostasis: Perioperative Risks and Management

BACKGROUND

Surgical and technological advances have resulted in the widespread adoption of microsurgical breast reconstruction. Many comorbidities that potentially might impair vasculature and wound healing are no longer considered contraindications for these procedures. However, some uncertainty still prevails regarding the perioperative management of patients with disorders of hemostasis.

METHODS

The authors combined a literature review with a retrospective chart review of patients with disorders of hemostasis who had undergone microsurgical breast reconstruction at the senior author's (J.F.) center between 2015 to 2020. Several disorders associated with thrombotic and/or hemorrhagic complications were identified, and a standardized risk assessment and management strategy was developed in cooperation with a hematologist.

RESULTS

Overall, 10 studies were identified comprising 29 patients who had a defined disorder of hemostasis and underwent microsurgical breast reconstruction. Seventeen microsurgical breast reconstructions were performed on 11 patients at the senior author's (J.F.) center. High factor VIII levels, heterozygous factor V Leiden, and heterozygous prothrombin mutation G20210A were the most common genetic or mixed genetic/acquired thrombophilic conditions. As expected, hereditary antithrombin, protein C, or protein S deficiencies were rare. Among hemorrhagic disorders, thrombocytopenia, platelet dysfunction, and von Willebrand disease or low von Willebrand factor levels were those factors most frequently associated with increased perioperative bleeding.

CONCLUSIONS

Patients should be screened for elevated risk of thrombosis or bleeding before undergoing microsurgical breast reconstruction, and positive screening should prompt a complete hematologic evaluation. Interdisciplinary management of these disorders with a hematologist is essential to minimize risks and to obtain optimal reconstructive results.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, IV.

Saphenous Vein Interposition Grafts in Lower Extremity Reconstruction: Appraisal of Technique and Case Series

Vascular microanastomosis is technically challenging in patients with calcified recipient and donor vessels. Inside-to-outside suturing can prevent plaque rupture and ensure full-thickness intimal approximation. Although this is the preferred technique for anastomosis of atherosclerotic vessels, direct connection of calcified arteries necessitates outside-to-inside suturing on one side of the anastomosis. Furthermore, it is difficult to achieve optimal vessel wall approximation in the setting of luminal size mismatch and rigid vasculature. We previously reported on the use of a saphenous vein interposition graft as a novel technique to achieve a flow-sparing anastomosis in patients with diffuse atherosclerosis who are undergoing free tissue transfer. This study further assesses outcomes of this technique in a series of patients and demonstrates a flap success rate of over 93% in patients with calcified recipient and donor microvasculature.

New, Innovative, Three-Dimensional In Vivo Model for High-Level Microsurgical and Supermicrosurgical Training: A Replacement for Animal Models

SUMMARY

Microsurgery and supermicrosurgery are surgical subdomains necessary for a large variety of surgical disciplines. So far, there is no training model for lymphatic surgery or perforator flap surgery, and the most commonly used microsurgical training models are living animals. However, the ethical principles of replacement, refinement, and reduction (the three Rs) of living animals for training purposes were implemented, highlighting the necessity of an animal-sparing microsurgical training model. Formed during embryogenesis, the chick chorioallantoic membrane resembles a highly vascularized, noninnervated membrane within fertilized chicken eggs. The aim of this study was to utilize the chorioallantoic membrane model as an innovative and versatile training model for supermicrosurgery and microsurgery that can reduce the number of animals used for these purposes. The variety of different sized vessels for the implementation of an anastomosis proved the chorioallantoic membrane model as a well-functioning supermicrosurgical and microsurgical training model. The circulatory system is resilient enough to withstand the mechanical stress applied to the tissue, and the patency of the implemented anastomosis can be tested for the verification of the procedures. In summary, the integration of the chorioallantoic membrane model into a surgical training program can benefit its quality by representing a realistic anatomical and physiological model with a high variety of vascular structures. Moreover, the chorioallantoic membrane model satisfies the principles of replacement, refinement, and reduction as an animal-sparing model, indicating the potential of this model as an innovative microsurgical training model for the improvement of surgical skills.

The Impossible Anastomosis: Intima-to-adventitia Suture Technique for Microanastomosis of Severely Calcified Arteries

Microsurgery in patients with advanced atherosclerosis is challenging. Calcified vessels can hinder microanastomosis, which precludes free flap reconstruction in those patients. We present a case of a female patient with stage 4 peripheral artery disease who had undergone mastectomy because of invasive breast cancer. During autologous breast reconstruction with a muscle-sparing transverse rectus abdominis free flap, we experienced difficulties during microanastomosis due to complicated plaques in an extremely calcified inferior epigastric artery. Also, the intima presented completely detached from the media, leading to a collapse of the vessel lumen. To prevent curling of the intima and prolapse of the atherosclerotic plaques into the vessel lumen, the intima was sutured to the adventitia by interrupted stitches. This maneuver led to eversion of the intima and facilitated the otherwise unfeasible anastomosis. The reconstructed breast showed adequate perfusion during the postoperative course. We present a technique to facilitate microanastomosis in severely calcified and fragile arteries.

Overcoming severe calcified lower extremity artery in lower limb salvage operation by using the Fogarty catheter and vein graft

BACKGROUND

With severe vascular calcifications, vascular clamp application and utilizing the vessel for free flap recipient vessel becomes impossible. These obstacles can be overcome with the Fogarty catheter and vein graft.

PATIENTS AND METHODS

When unclampable artery was encountered intraoperatively, a vein graft was used to make a clampable recipient site for six diabetic foot patients (ages from 42 to 80). The end of the Fogarty catheter was inserted into the proximal end of the vein graft and the transected calcified vessel in sequence, and the balloon of the catheter was used as an intraluminal tourniquet. The remaining end of the vein graft was connected to the distal vessel with a vascular clamp.

RESULTS

Five short vein graft revascularization for segmental arterial occlusion, one long vein graft for recipient artery elongation was done (lengths from 2 to 13.8 cm). Three delayed, and two immediate anterolateral thigh flaps (sizes from 15 to 150 cm² ) were performed, and one patient received vein graft revascularization surgery only. Postoperative vascular sonography of all six patients showed well-maintained patency. Minor flap marginal disruption occurred at two patients but healed with conservative care. Postoperative follow-up was done for 1-18 months (average 7.17). Limb salvage was achieved for five patients and all five free flaps survived. However, for one patient, arterial restenosis at popliteal artery a month later lead to major amputation.

CONCLUSION

Using a Fogarty catheter and a vein graft may obtain perfect hemostasis during micro-anastomosis and achieve successful microvascular reconstruction in patients with severely calcified vessels.

Ankle Brachial Index Predicts for Difficulties in Performing Microvascular Anastomosis

PURPOSE

In reconstructive microsurgery, severe arteriosclerosis is a known predictor for free flap failure because of problems with the vascular anastomosis. We investigated whether the ankle brachial index (ABI) could be a suitable preoperative measurement for the prediction of compromise regarding vascular anastomosis in patients undergoing microsurgical reconstruction.

MATERIAL AND METHODS

We conducted a prospective cohort study of patients who had undergone reconstructive microvascular surgery in a tertiary care center from 2015 to 2017. The ABI was preoperatively assessed by dividing the systolic blood pressure measured at the ankle by the brachial systolic blood pressure. Results from 0.9 to 1.3 are within the physiologic range. Values less than 0.9 indicate moderate to severe arteriosclerosis, and those greater than 1.3 indicate the major form of arteriosclerosis with complete calcification of the tunica media. The ABI value correlated with the ease of the anastomosis (rated from 1 [very straightforward] through 5 [very difficult]), gross examination findings (intraluminal plaque [yes vs no]), and the necessity of plaque removal before anastomosis (yes vs no). In addition, cross-sectional specimens were obtained from the arteries and veins of the donor and recipient sites intraoperatively. The specimens were rated histologically for the arteries and veins using an ordinal scale. Histologic evaluation was performed to confirm and objectify the results from the ABI. Statistical analysis was performed using SPSS software, version 24.0 (IBM Corp, Armonk, NY) and t tests, analysis of variance, and χ² tests.

RESULTS

The sample included 41 patients with a mean age of 56.7 years; 59% were men. The mean ABI was 1.06. The mean ease of anastomosis was 1.8. The mean ABI was associated with the ease of anastomosis. A pathologic ABI was significantly related to problems with the arterial anastomosis (P = .004) and increased arteriosclerosis in the arteries from the donor (P = .047) and recipient (P = .036) sites.

CONCLUSIONS

A pathologic ABI was associated with increased difficulty with the microvascular anastomosis.

Vein conduit for end-to-side anastomosis of a calcified vessel in lower extremity free flap reconstruction

BACKGROUND

As the microsurgical and interventional revascularization techniques are evolving, traditionally amputated limbs are now challenged to salvage. However, a calcified recipient vessel is a common but challenging problem encountered in lower extremity reconstruction.

METHODS

An end-to-side anastomosis of a vein graft (1.5-3.5 cm in length) was performed to the recipient vessel when it was difficult to clamp the recipient vessel near the defect because of the inelastic and hard vessel wall. The vascular clamp was applied to the vein graft, and the flap's pedicle was anastomosed to the vein graft.

RESULTS

A total of 18 free flaps (10 ALT cases, 4 TDAP cases, 2 PAP cases, and 2 SCIP cases) were anastomosed with a bridge vein graft to the heavily calcified recipient vessels (7 ATA cases, 3 PTA cases, 7 DPA cases, and 1 MPA case). Overall flap survival rate was 83.3%. Limb salvage rate was 93.7%, and anastomosis patency rate was 94.4% CONCLUSION: Vein conduit in an end-to-side anastomosis of severely calcified recipient vessels shows a reasonable limb salvage rate. It acts as a buffer, which makes microscopic vessel manipulation easier. If vessel calcification is the only drawback for a free flap reconstruction, then a vein graft needs to be prepared instead of an amputation. This method may extend the surgical option to more high-risk patients in lower extremity microsurgical reconstruction and increase the limb salvage rate.

Detection of thrombosis in microvessels with indocyanine green videoangiography

Atherosclerosis is a systemic condition that is responsible for many diseases, and becomes a problem in cases where plaques form at several sites. The formation of a thrombotic embolus may jeopardise vascular operations, including microvascular anastomoses in replantation procedures or free tissue transfers. A mobile imaging tool for the detection of thrombosis preoperatively or intraoperatively would be valuable. An intimal injury, simulating removal of atherosclerotic plaques, was made microsurgically in 60 rat aortas, and results were analysed macroscopically, histologically, and with intraoperative indocyanine green (ICG) videoangiography immediately postoperatively. The Spearman and Pearson correlation tests were used to compare the three techniques. The sensitivity and specificity of ICG videoangiography was calculated in relation to both macroscopic and histological results. Detection of thrombosis was possible in 25 cases, and in 18 cases no thrombosis was correctly diagnosed by all methods used. In 31 of 60 specimens formation of thrombus was detected histologically, and in 29 of 60 examinations it was detected clinically, which yielded a correlation of 93.5% between the two examinations. Macroscopic analysis correlated better with ICG videoangiography (sensitivity 86.2% and specificity 64.5%) than histological observations (sensitivity 80.6% and specificity 62.1%). There was a significant correlation among all comparisons (each p≤0.001) with correlation indexes of 0.94, 0.52, and 0.44 for macroscopic/histological, clinical/ICG videoangiographic, and ICG videoangiographic/histological results, respectively. Our results show that ICG videoangiography is an important method for the detection of formation of acute thrombi and may be an important tool in vascular procedures.

Impact of different antithrombotics on the microcirculation and viability of perforator-based ischaemic skin flaps in a small animal model

The effects of antithrombotic drugs on random and free flap survival have been investigated in the past, but the experimental and clinical results are not in agreement. A perforator-based critical ischaemia model was used to evaluate the effects of different perioperatively administered pharmaceutical agents on tissue ischaemia and to assess the potential additional haemorheological or vasodilative effects of antithrombotics on flap microcirculation. Combined laser Doppler flowmetry and remission spectroscopy revealed an increase in certain microcirculation parameters in most groups in comparison with saline controls, and these changes correlated with flap survival. Clopidogrel and hirudin significantly improved the amount of viable flap tissue in comparison with controls, while unfractioned heparin had a negative effect on flap survival. Low molecular weight heparin, aspirin, pentoxifylline, and hydroxyethyl starch had no impact on the amount of viable flap tissue. A higher complication rate was observed in all experimental groups, but only clopidogrel had a negative impact on the flap viability. Our results add to the body of evidence supporting the conclusion that perioperative antithrombotic treatment improves flap survival. Clopidogrel and hirudin are effective pharmacological agents that significantly increased the viability of perforator-based skin flaps in rats, but at a higher risk of postoperative bleeding.

Microsurgical reconstruction of the head and neck--current concepts of maxillofacial surgery in Europe

INTRODUCTION

Microvascular surgery following tumour resection has become an important field of oral maxillofacial surgery (OMFS). This paper aims to evaluate current microsurgical practice in Europe.

METHODS

The questionnaire of the DOESAK collaborative group for Microsurgical Reconstruction was translated into English, transformed into an online based survey and distributed to 200 OMFS units with the aid of the European Association for Cranio-Maxillo-Facial Surgery (EACMFS).

RESULTS

65 complete and 72 incomplete questionnaires were returned. Hospitals from the United Kingdom, France, Italy, the Netherlands, Spain, Belgium, Greece, Slovenia and Lithuania participated. 71% of contributing centres were university hospitals, 87% out of these perform microvascular tumour surgery at least on a two-weekly base. Overall complication rate was at around five percent. Most frequently used transplants were the radial forearm flap and the fibular flap. The perioperative management varied widely. Success factors for flap survival, however, were uniformly rated, with the surgical skill being the most important factor, followed by the quality of postoperative management. Medication seems to play a less important role.

CONCLUSION

Within Europe microvascular surgery is a common and safe procedure for maxillofacial reconstructive surgery in the field of OMFS. While there is a major accordance for the surgical procedure itself and the most frequently used flaps, perioperative management shows a wide variety of protocols with low presumed impact on surgical outcome.

Internal mammary perforator vessels as recipient site for microsurgical breast reconstruction: a comparative histomorphometric analysis and incidence of degenerative vascular changes

BACKGROUND

In microsurgical breast reconstruction, an adequate selection of recipient vessels is crucial for a successful outcome. Although the internal mammary (IM) vessels offer an attractive option, the internal mammary perforator (IMP) vessels are becoming a reliable alternative. The purpose of this study is to investigate the external diameters, lumen area, and atherosclerotic lesions changes of the IMP, IM, and deep inferior epigastric (DIE) vessels through quantitative and qualitative histomorphometric analysis.

METHODS

Ninety-six vessels of bilateral IM, IMP, and DIE vessels from 16 fresh female cadavers were evaluated. Mean age was 54.06 ± 5.7 years. External diameters, lumen area, and degenerative changes of the tunica intimae and media were analyzed by qualitative histomorphometric analysis.

RESULTS

Seventy-one vessels (20 IM, 31 IMP, and 20 DIE vessels) were included in the final histological analysis. A statistically lower external diameters and lumen area were presented by the IMP. The DIE vessels showed a lower incidence (10%) of moderate and severe intimal layer degenerative changes (P = 0.0589). The IMP and DIE vessels showed a lower incidence (9.4 and 25%, respectively) of major media layer degenerative changes (P = 0.0001). No major arterial degenerative lesions were observed in the IMP arteries.

CONCLUSION

Although the IMP external diameters and lumen area were lower than the IM, the results of this study indicated that the tunica media layer in the IMP is less damaged than the other recipient vessels. The results of the comparative histological study permitted to describe additional advantages and disadvantages of using IMP as a recipient vessel for free flap breast reconstruction.

Introduction of a microsurgical in-vivo embolization-model in rats: the aorta-filter model

Vascular thrombosis with subsequent distal embolization remains a critical event for patients. Prevention of this life-threatening event can be achieved pharmacologically or mechanically with intravascular filter systems. The ability to evaluate the risk of embolization of certain techniques and procedures in vascular and microvascular surgery, such as, tissue glue or fibrin based haemostatic agents lacks convincing models. We performed 64 microvascular anastomoses in 44 rats, including 44 micro-pore polyurethane filter-anastomoses and 20 non-filter anastomoses. The rats were re-anesthetized and the aorta was re-exposed and removed four hours, three, seven, fourteen, thirty-one days, and six months postoperatively. The specimens were examined macro- and microscopically with regard to the appearance of the vessel wall, condition of the filter and the amount of thrombembolic material. Typical postoperative histopathological changes in vessel architecture were observed. Media necrosis was the first significant change three days postoperatively. Localized intimal hyperplasia, media necrosis, increase of media fibromyocytes and adventitial hypercellularity were seen to a significant extent at day seven postoperatively. Significant neovascularization of adventitia adjacent to the filter was seen after 14 days. A significant amount of thrombotic material was seen after four hours, three and 14 days interval. Only three intravascular filters became completely occluded (6.82%). The aorta-filter-anastomosis model appeared to be a valid in-vivo model in situations at risk for thrombembolic events, for microsurgical research and allowed sensitive analysis of surgical procedures and protection of the vascularized tissue. It may be suitable for a wide range of in-vivo microvascular experiments particularly in the rat model.

Identification of perioperative risk factor by laser-doppler spectroscopy after free flap perfusion in the head and neck: a prospective clinical study

The aim of this study was to evaluate perioperative flap perfusion using noninvasive monitoring with a laser-Doppler flowmetry and spectrophotometry unit (O2C) and identify whether perioperative blood flow, velocity, hemoglobin level (Hb), and oxygen saturation (SO2 ) measured could be used as indicators of free flap success. Measurements of blood flow, velocity, Hb, and SO2 were performed in 196 microvascular flaps, which had been transferred into the oral cavity to reconstruct ablative defects after surgery for oral cancer. The values were calculated superficially on the skin surface and at a depth of 8 mm. The results showed that perioperative absolute values measured were not associated with an increased rate of microvascular revisions or free flap failure. Independent predictors of microvascular revisions at the first postoperative day were the development of a falling trend in superficial and deep blood flow, and velocity in comparison with baseline values of variables measured. On day 2, all superficial and deep values of Hb, flow, and velocity were independent prognostic factors (P < 0.01), demonstrated as a downward trend were associated with a need for revision. The superficial and deep values of SO2 (P = 0.59 and 0.43, respectively) were not associated with ultimate free flap failure. This is the first clinical study to demonstrate that during early free flap integration to the recipient site different parameters of perfusion and oxygenation play an important role at different points of time. Within the first two postoperative days, changes in these parameters can help influence the decision to revise microvascular anastomoses.

Vascular trauma in geriatric patients: a national trauma databank review

BACKGROUND

The epidemiology of vascular injuries in the geriatric patient population has not been described. The purpose of this study was to examine nationwide data on vascular injuries in the geriatric patients and to compare this with the nongeriatric adult patients with respect to the incidence, injury mechanisms, and outcomes.

METHODS

Geriatric patients aged 65 or older with at least one traumatic vascular injury were compared with an adult cohort aged 16 years to 64 years with a vascular injury using the National Trauma Databank version 7.0.

RESULTS

During the study period, 29,736 (1.6%) patients with a vascular injury were identified. Of those, geriatric patients accounted for 7.6% (2,268) and the nongeriatric adult patients accounted for 83.1% (n=24,703). Compared with the nongeriatric adult patients, the geriatric vascular patients had a significantly higher Injury Severity Score (26.6±17.0 vs. 21.3±16.7; p<0.001) and less frequently sustained penetrating injuries (16.1% vs. 54.1%; p<0.001). The most commonly injured vessels in the elderly were vessels of the chest (n=637, 40.2%), including the thoracic aorta and innominate and subclavian vessels. The overall incidence of thoracic aorta injuries was significantly higher in geriatric patients (33.0% vs. 13.9%; p<0.001) and increased linearly with progressing age. After adjusting for confounding factors, geriatric patients demonstrated a fourfold increase in mortality following vascular injuries (adjusted odds ratio, 3.9; 95% confidence interval, 3.32-4.58; p<0.001).

CONCLUSION

Vascular trauma is rare in the geriatric patient population. These injuries are predominantly blunt, with the thoracic aorta being the most commonly injured vessel. Although vascular injuries occur less frequently than in the nongeriatric cohort, in the geriatric patient, vascular injury is associated with a fourfold increase in adjusted mortality.

Combined latissimus dorsi and serratus anterior flaps for pelvic reconstruction

In recurrent pressure sores, adjacent tissue has already been consumed by multiple surgeries. Additional problems are several co-morbidities of patients. Especially, severe atherosclerosis would be a contraindication for using free flaps. However, microsurgical techniques allow circumventing these limitations and preparing even severely atherosclerotic vessels. We performed a total of eight sacral pressure sore coverage in our standardized fashion, using the free combined latissimus dorsi and serratus anterior free flaps. All patients had severe atherosclerosis and needed large soft tissue coverage of the sacral defects. Five patients presented after bowel resection, three with recurrent sacral pressure sores. The average follow-up was 12 months. Postoperatively, all patients were allowed to be prone on the operated area. One minor wound dehiscence was sutured in local anesthesia. CT imaging analysis of the pelvis showed complete void space coverage. The combined latissimus dorsi and serratus anterior flaps are a valuable tool for pelvic reconstruction in our hands. In addition, severe atherosclerosis should not be considered an obstacle to microsurgery and the use of free flaps.

Pediatric vs adult vascular trauma: a National Trauma Databank review

INTRODUCTION

The purpose of this study was to examine nationwide data on vascular injuries in children and to compare pediatric and adult patients with respect to the incidence, injury mechanisms, and outcomes.

METHODS

This is a National Trauma Databank analysis based on dataset version 7.0 (spanning a 5-year period ending December 2006). Pediatric patients under the age of 16 with at least one reported diagnosis of a vascular injury were compared to the adult cohort aged 16 and greater with a vascular injury.

RESULTS

During the study period, of 251,787 injured patients younger than 16 years, 1138 (0.6%) had a vascular injury. The incidence in patients 16 years or older was significantly higher, at 1.6% (P < .01). Compared to the adult vascular patients, pediatric patients had a significantly lower Injury Severity Score (16.8 +/- 14.9 vs 26.3 +/- 16.7, P < .001) and encountered less frequently penetrating injuries (41.8% vs 51.2%, P < .001). The most commonly injured vessels in the pediatric population were vessels of the upper extremity (424 patients or 37.9%). The overall incidence of thoracic aortic injuries in children was seven-fold lower compared to the incidence in adults (0.03% vs 0.21%). After adjusting for confounding factors, pediatric patients demonstrated improved survival following vascular injuries (adjusted odds ratio, 0.60; 95% CI, 0.45-0.79; P < .001). No significant difference was identified in the rate of amputation between pediatric and adult patients who had sustained upper or lower extremity vascular injuries.

CONCLUSION

Vascular trauma in the pediatric population is uncommon, occurring in only 0.6% of all pediatric trauma patients. Although less frequent than adults, a significant proportion was due to penetrating injury. Vessels of the upper extremity were the most commonly injured and were associated with low mortality. Injuries of the thoracic aorta are rare. Overall, pediatric patients had an improved adjusted mortality when compared to adults.

Ischemic toe encountered during harvesting: report of 6 cases

Local vessel disease causing lack of arterial inflow at the time of toe harvesting represents a surgical emergency. In a personal experience of 194 toe transfers to the hand, 6 cases (in 4 patients) were found to have diseased vessels at the first web to the point that acute ischemia of the toe occurred when the tourniquet was released at the lower limb. We report our experience in these 6 cases.

Microvascular breast reconstruction pedicle thrombosis: How long can we wait?

Re-exploration plays a key role in salvaging vascularly compromised free flaps. A retrospective review of 290 free flaps in breast reconstruction was performed to determine whether the time delay between thrombosis detection and surgical re-exploration had any effect on flap salvage. Overall flap success was 97.6%. Postoperative thrombosis requiring re-exploration was documented in 6.2% cases. Fifty-five percent of take-back flaps were salvaged and 45% were lost. The median time between detection of flap compromise to surgical incision was 128 min in our saved flaps, and 228 min in the lost flap group. Our preliminary data suggests that re-exploration within 188 min may improve flap salvage.