A systematic review of the scientific evidence of venous supercharging in autologous breast reconstruction with abdominally based flaps.

BACKGROUND: Abdominally based free flaps are commonly used in breast reconstruction. A frequent complication is venous congestion, which might contribute to around 40% of flap failures. One way to deal with it is venous supercharging. The primary aim of this study was to investigate the scientific evidence for the effects of venous supercharging. METHODS: A systematic literature search was conducted in PubMed, CINAHL, Embase, and Cochrane library. The included articles were critically appraised, and certainty of evidence was assessed using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach. RESULTS: Thirty-six studies were included. Most studies had serious study limitations and problems with directness. Three studies report 'routine' use of venous supercharging and performed it prophylactically in patients who did not have clinical signs of venous congestion. Seventeen studies report on flap complications, of which one is a randomised controlled trial demonstrating statistically significant lower complication rates in the intervention group. The overall certainty of evidence for the effect of a venous supercharging on flap complications, length of hospital stay and operative time, in patients without clinical signs of venous congestion, is very low (GRADE ⊕ ⊕ ⊝ ⊝), and low on and surgical takebacks (GRADE ⊕ ⊕ ⊝ ⊝). Twenty-one studies presented data on strategies and overall certainty of evidence for using radiological findings, preoperative measurements, and clinical risk factors to make decisions on venous supercharging is very low (GRADE ⊕ ⊝ ⊝ ⊝). CONCLUSION: There is little scientific evidence for how to predict in which cases, without clinical signs of venous congestion, venous supercharging should be performed. The complication rate might be lower in patients in which a prophylactic venous anastomosis has been performed. TRIAL REGISTRATION: PROSPERO (CRD42022353591).

Superficial outside-flap shunt (SOS) is associated with a low incidence of postoperative DIEP flap venous congestion: A single-institution retrospective cross-sectional study.

INTRODUCTION: Venous congestion burdens up to 15% of deep inferior epigastric artery perforator (DIEP) flap breast reconstructions. For these cases, venous augmentation by superficial outside shunt (SOS) is associated with 100% success in secondary salvage surgeries. Intraoperative venous augmentation using other techniques yields a 0.3% rate of return to theater due to venous congestion, but there is no evidence assessing the effectiveness of the SOS technique applied preventively. Comparing this preventive approach to data prior to its implementation, we expect to find a reduced number of venous congested flaps with reduced flap losses and revision surgeries. PATIENTS AND METHODS: This retrospective cross-sectional study involved DIEP flap breast reconstructions performed between 2011 and 2020. The control group included patients receiving additional venous anastomosis as a secondary salvage procedure. The "preventive SOS group" included patients who received preventive SOS during the main surgery. Age, body mass index (BMI), pregnancies, perioperative treatments (neoadjuvant or adjuvant chemo or radiotherapy), follow-up complications (arterial ischemia, venous congestion, hematomas, partial/total flap loss), and revision surgeries (breast debridement, flap remodeling) were recorded and compared. RESULTS: Within 695 flaps performed, 397 flaps were included in the control group, and 298 flaps were included in the preventive SOS group. The groups were homogeneous for age (p = 0.418), BMI (p = 0.747), and flap weight (p = 0.064). Fifty-one flaps (12.8%) in the control group compared to zero (0.0%) in the preventive SOS group required return to theater (p < 0.001). CONCLUSIONS: We reported encouraging preliminary results for SOS to prevent DIEP flap venous congestion. These results must be validated prospectively.

The Results of Preoperative Use of Topical Brimonidine in Strabismus Surgery.

Purpose: In this study, we wanted to retrospectively evaluate the effect of the use of topical brimonidine on intraoperative bleeding and surgical hemostasis before strabismus surgery. Methods: Brimonidine tartrate 0.15% (Brimogut, Bilim Ilac, Turkey) eye drops were applied 6 and 3 min before surgery to 44 eyes of 22 patients in group 1 for vasoconstriction. Drops were not applied to 46 eyes of 23 patients in group 2. Preoperative and postoperative photographs and video images were taken. Black-and-white images were used to define the surface areas of the blood vessels. The surface area was calculated by counting the black pixels with ImageJ software. Results: In group 1, redness of eye was observed, on average, at preoperative 339.25 ± 11.52 pixels and intraoperative 247.93 ± 10.63 pixels (P < 0.001). But there was no change in group 2 (preoperative 338.87 ± 8.45 pixels to intraoperative 339.71 ± 9.52 pixels, P > 0.05). The incidence of intraoperative bleeding evaluated by the number of eyes on which cautery was used shows that it was significantly less in group 1 than in group 2 (P < 0.001). Conclusions: The use of topical brimonidine before strabismus surgery facilitates clear monitoring of anatomical structures during surgery by effectively controlling hemorrhage. In the postoperative period, it significantly reduces subconjunctival hemorrhage.

Arterial only anastomosis associated with modified Baudet technique in ear replantation: Case reports and literature review.

BACKGROUND: Total ear amputation is a relatively rare trauma with an absolute indication for surgical treatment. Numerous techniques for auricular reconstruction have been described. When local and general conditions allow microsurgical replantation, this must be the first choice. We propose the association of microsurgical techniques with some modification (modified Baudet technique) to obtain higher survival rate of the reimplanted stump. METHODS: This study included cases of 3 male patients with total ear amputation, the injuries and their mechanism (workplace accident) being identical. Chief complaints were pain, bleeding, important emotional impact due by an unaesthetic appearance. The established diagnosis was traumatic complete ear amputation (grade IV auricular injury according to Weerda classification). Microsurgical replantation was performed only with arteriorraphy, and no vein anastomosis. Cartilage incisions and skin excisions were made to enlarge the cartilage-recipient site contact area. Medicinal leeches were used to treat venous congestion, to which systemic anticoagulant therapy was added. RESULTS: The results showed the survival of the entire replanted segment in all cases, with good function and esthetical appearance. Patients were fully satisfied with the final outcome. CONCLUSION: Microsurgical replantation is the gold standard, for the surgical treatment of total ear amputation. We believe that cartilage incisions and the increased surface of contact between cartilage and recipient site has an adjuvant role in revascularization of the amputated stump (with only arterial anastomosis) and the use of hirudotherapy helps to relieve early venous congestion.

Safety and effectiveness of early compression of free flaps following lower limb reconstruction: A systematic review.

INTRODUCTION: Early postoperative compression of free flaps for lower limb reconstruction remains controversial. It may reduce venous congestion and promote the resolution of oedema. However, concerns remain regarding inadvertent pedicle compression, which may lead to flap failure. The aim of this systematic review was to determine the safety and effectiveness of this intervention. METHODS: A systematic review was designed in compliance with PRISMA. MEDLINE and EMBASE databases were searched. Parallel screening, selection of eligible studies, and data gathering were carried out by two independent authors. A formal risk of bias assessment was included along with the appraisal of outcomes. RESULTS: A total of 847 abstracts were retrieved and 262 free flaps for lower limb reconstruction were identified in ten eligible articles. The overall flap failure rate for patients who underwent early postoperative compression was 1.6%. Apart from flap failure rates, there were no other outcomes consistently reported and none of the studies included a no-compression group for comparison. DISCUSSION: All included studies had methodological flaws, resulting in a high risk of bias. Nevertheless, there was consistent reporting of flap failure as a postoperative outcome. Compression of free flaps in the context of lower limb reconstruction does not appear to be associated with a higher flap failure rate compared with other series. Compression bandages may reduce the pain associated with dangling regimes. However, there is no evidence to support that free flap compression in the context of lower limb reconstruction is associated with any other clinical benefit.

The Results of Preoperative Topical Brimonidine Usage in Pterygium Surgery.

Purpose: To evaluate the reduction of conjunctival and episcleral hyperemia and bleeding in pterygium surgery following the use of topical brimonidine preoperatively. Methods: In this study, 45 patients who had undergone pterygium surgery under topical anesthesia were enrolled. Brominidine tartrate 0.15% eye drops were applied topically to 25 eyes of 25 patients at the sixth and third minutes preoperatively, and no drops were applied to 20 eyes of 20 patients for vasoconstriction. Preoperative and postoperative photographs and video images were taken. Results: Vasoconstriction effects of topical brimonidine tartrate on surface vessels were observed. The surface area of blood vessels was reduced 60% within 5 min; this effect was observed with the help of Photoshop and ImageJ programs and it lasted for ∼20 min. The surgery lasts for 7 min, on average, so the conjunctival whitening formed by brimonidine tartrate provides a safe and comfortable operative area throughout the surgery. Conclusion: We recommend applying brimonidine tartrate before pterygium surgery due to its conjunctival whitening effect to provide a safe and comfortable operative area throughout the surgery.

Protective effects of Chrysin against memory impairment, cerebral hyperemia and oxidative stress after cerebral hypoperfusion and reperfusion in rats.

Stroke is devastating and a leading cause of morbidity and mortality worldwide. Cerebral ischemia-reperfusion and its subsequent reactive hyperemia lead to neuronal damage in the hippocampus and cognitive decline. Chrysin (5, 7-dihydroxyflavone) is a well-known member of the flavonoid family with antioxidant and neuroprotective effects. Therefore, in the present study, the aim was to investigate whether chrysin will be able to recover the brain function caused by ischemia-reperfusion (I/R) in rats. Adult male Wistar rats (250-300 g) were randomly divided into five groups: and submitted to cerebral I/R or a sham surgery after three-weeks of pretreatment with chrysin (CH; 10, 30 and 100 mg/kg; P.O.) and/or normal saline containing %5 DMSO. Subsequently, sensorimotor scores, cognition, local cerebral blood flow, extracellular single unit, and histological parameters were evaluated following I/R. Hippocampus was used to evaluate biomarkers including: oxidative stress parameters and prostaglandin E2 (PGE2) using ELISA kits. Data showed that pretreatment with chrysin significantly improved sensorimotor signs, passive avoidance memory, and attenuated reactive hyperemia, and increased the average number of spikes/bin (p < 0.001). Furthermore, chrysin pre-treatment significantly decreased the levels of MDA, NO, and PGE2 (p < 0. 001), while increased the levels of GPX and the number of surviving cells in the hippocampal CA1 region (p < 0.01, p < 0.001; respectively). This study demonstrates that chrysin may have beneficial effects in the treatment of cognitive impairment and help recover the brain dysfunction induced by I/R.

Implementing local cooling to increase skin tolerance to ischemia during normal seating in people with spinal cord injury.

The purpose of this study was to investigate the effectiveness of local cooling in reducing reactive hyperemia after ischemia at the ischial tuberosities for people with spinal cord injury (SCI) during normal seating. The degree of the reactive hyperemic response is indicative of the extent of cellular stress caused by the ischemia. We hypothesized that reactive hyperemic skin blood flow (SBF) responses will be lower when local cooling is implemented by the wheelchair seat cushion. This study used a repeated measures design, and each subject underwent two conditions: normal seating with temperature control 'on' (cooling) and 'off' (non-cooling) for 30 min. Twenty-three participants with traumatic SCI were recruited. SBF and skin temperature were collected before, during and after seating. SBF signals were processed with short-time Fourier analyses to examine the underlying vascular control mechanisms, including the following (corresponding frequency bands): metabolic (0.0095-0.02 Hz), neurogenic (0.02-0.05 Hz), and myogenic (0.05-0.15 Hz) spectral densities. Our results showed that with cooling, skin temperature decreased (range -0.4 ~ -3.1 °C, p = 0.002), and reactive hyperemia parameters (normalized peak SBF and perfusion area) were reduced (p = 0.02, p = 0.033, respectively). In addition, changes in normalized peak SBF (non-cooling - cooling) was moderately correlated with changes in normalized metabolic and neurogenic spectral densities. Our findings suggested that local cooling has a positive effect on reducing the cellular stress caused by ischemia during normal seating. Metabolic and neurogenic SBF control mechanisms may play a minor role. Further exploration of the effect of temperature control on pressure injury prevention is warranted.

Impaired microvascular reactivity after eccentric muscle contractions is not restored by acute ingestion of antioxidants or dietary nitrate.

Unaccustomed eccentric exercise leads to impaired microvascular function but the underlying mechanism is unknown. In this study, we evaluated the role of oxidative stress and of nitric oxide (NO) bioavailability. Thirty young men and women performed eccentric contractions of the tibialis anterior (TA) muscle (ECC), with the contralateral leg serving as nonexercising control (CON). Participants were randomized into three groups ingesting an antioxidant cocktail (AO), beetroot juice (BR) or placebo 46 h postexercise. At baseline and 48 h postexercise, hyperemic responses to brief muscle contractions and 5 min of cuff occlusion were assessed bilaterally in the TA muscles using blood oxygen level dependent (BOLD) magnetic resonance imaging. Eccentric contractions resulted in delayed time-to-peak (~22%; P < 0.001), blunted peak (~21%; P < 0.001) and prolonged time-to-half relaxation (~12%, P < 0.001) in the BOLD response to brief contractions, with no effects of AO or BR, and no changes in CON. Postocclusive time-to-peak was also delayed (~54%; P < 0.001) in ECC, with no effects of AO or BR, and no changes in CON. Impaired microvascular reactivity after eccentric contractions is confined to the exercised tissue, and is not restored with acute ingestion of AO or BR. Impairments in microvascular reactivity after unaccustomed eccentric contractions may result from structural changes within the microvasculature that can diminish muscle blood flow regulation during intermittent activities requiring prompt adjustments in oxygen delivery.

Does Size Matter: Evaluating the Difference between Right and Left Internal Mammary Veins in Free Flap Breast Reconstruction.

BACKGROUND: Venous congestion in breast free flap reconstruction continues to be a major reason for flap compromise requiring reoperative exploration and possible flap failure. We aim to investigate whether size of the internal mammary vein (IMV) (1) varies between the left and right sides, (2) changes with certain patient demographics or preoperative factors, and (3) correlates with postoperative complications. METHODS: We performed a retrospective cohort study examining all patients undergoing free flap breast reconstruction from September 2005 to March 2016 using internal mammary recipient veins. Venous coupler size was used as a surrogate measure of IMV diameter. Preoperative patient characteristics and factors were collected. Postoperative outcomes assessed included thrombosis, flap loss, fat necrosis, and mastectomy flap necrosis. Multivariate analyses were performed to evaluate if preoperative factors affected IMV diameter and to determine if coupler size and flap side were independent risk factors for postoperative complications. RESULTS: We examined 372 patients with a total of 561 flaps. One hundred eighty-nine patients received bilateral flaps with the IMV as a recipient. The right IMV (n = 286, average = 2.97 mm, standard deviation [SD] = 0.41) was significantly larger than the left (n = 275, average = 2.89, SD = 0.35, p = 0.008). Preoperative factors and postoperative complications were not statistically different between the left and right cohorts. The multivariable linear regression model with coupler size as the dependent variable found older age trended toward a larger coupler size but this was not significant (p = 0.05). In multilinear regression analysis, the postoperative outcomes did not have significant covariates. CONCLUSION: We found that IMV size significantly differs between the right and the left sides. However, incidence of postoperative complications was not significantly different between the left and right sides, and the multivariate analyses did not identify flap side as an independent risk factor for adverse outcomes. Prospective studies evaluating actual IMV diameter and associated complications may potentially elucidate clinical significance.

A Theoretical Model Describing the Dynamics of Venous Flow in the DIEP Flap.

BACKGROUND: The deep inferior epigastric artery flap is an integral component of autologous breast reconstruction. The technical aspects of performing the flap have been well-established. A prior mathematical model suggested using the largest perforator and concluded that the inclusion of additional perforators may decrease resistance and increase flow, but at the downside of increased tissue trauma. Many complications may result from inadequate venous drainage of the flap and the same mathematical concepts may be applied. We attempt to give a mathematical model, based on the physics of flow and properties of circuits, to explain clinical observations regarding venous drainage of the flap and the complications that may arise. METHODS: We compare the different possible venous drainage systems of a perforator flap to a complex circuit with multiple resistances. Multiple venous perforators will be represented by resistances in parallel, while the deep and superficial drainage systems will be represented by a complex circuit loop. RESULTS: Drainage of the flap may be optimized through the deep drainage system if the venous perforators are of sufficient size. Inclusion of additional perforators may decrease resistance and enhance drainage. Salvage procedures may be necessary when the venous perforators are insufficient in size or when there are insufficient connections between the deep and superficial systems. CONCLUSION: A single large sized vessel may provide adequate drainage in most DIEP flaps, while the use of multiple vessels may enhance drainage upon the encounter of smaller vessels. Salvage procedures may be needed to relieve venous congestion as the design of the venous system becomes more complicated.

Comparison of propeller perforator flap and venous supercharged propeller perforator flap in reconstruction of lower limb soft tissue defect: A prospective study.

INTRODUCTION: In lower limbs, reliability of propeller perforator flaps (PPF) remains uncertain. The main complication is venous congestion, which can lead to distal necrosis. We aim to highlight if venous supercharging of PPF could substantially limit complications in lower limb coverage. METHODS: Between 2011 and 2016, we developed a standardized procedure of venous supercharging in the lower limb reconstruction with PPF using saphenous veins anastomosis. Then, we prospectively compared a consecutive series of 30 PPF to cover lower limbs defect, with a consecutive series of 30 venous-supercharged PPF (vsPPF). Etiologies of trauma, flap harvesting, complications, and outcomes were compared. RESULTS: The etiologies of the defect were acute trauma in 67.6% of reconstruction with PPFs and 60% of reconstruction with vsPPFs (P = 0.826). The average size of the skin paddle was 48.1 ±18.2 cm2 for PPF and 58.9 ±19.5 cm2 for vsPPF, and the average arc of rotation was 126.7° ±33.1 for PPF and 121.3° ±31.9 for vsPPF. The average sizes and rotation arcs between the two flaps were not significantly different (P = 0.031, P = 0.527). The operative time was significantly increased for vsPPF when compared to PPF procedure (128.8 ±8.5 minutes vs. 81.3 ±10.1 minutes, P < 0.001). Venous congestion was significantly higher in PPF with 11 cases than in vsPPF with two cases (36.7% versus 6.7%, P = 0.010). Distal necrosis were significantly higher in PPF with nine cases than in vsPPF with 1 cases (30% versus 3.3%, P = 0.012). Following poor flap evolution, stitches removal was significantly more frequent in PPF with 11 cases than in vsPPF with one case (36.7% vs 3.3%, P = 0.002). Leeches application was significantly more frequent for PPF procedures with nine cases, than for vsPPF with one case (30% vs 3.3%, P = 0.012). The average length of hospital stay for PPF was significantly longer than for vsPPF (8.78 versus 7.11 days, P = 0.026). CONCLUSION: The vsPPF is a reliable alternative to PPF to cover small- and medium-size defect in lower limbs, reducing venous congestion and overall complications.

Prelaminated extended temporoparietal fascia flap without tissue expansion for hemifacial reconstruction.

BACKGROUND: Disfigurement of the face caused by postburn scars, resected congenital nevi and vascular malformations has both functional and psychological consequences. Ideal reconstruction of the facial components requires producing not only function but also the better appearance of the face. The skin of the neck, supraclavicular or cervicothoracic regions are the most commonly used and the most likely source of skin for facial reconstruction in those techniques which prefabrications with tissue expansion are used. This retrospective cohort study describes the two staged prelaminated temporoparietal fascia flap which eliminates the usage of tissue expansion by using skin graft harvested from the neck and occipital region and the application of this flap for the lower three-fourths of the face. METHOD: 5 patients received prelaminated temporoparietal fascia flap without tissue expansion for facial resurfacing. The mean age at surgery was 39, 2 years (range, 17-60 years). The average follow up was 21.6 months (range, 10-48 months). RESULT: The size of the raised prelaminated temporoparietal fascia flaps ranged from 9 × 8 cm to 14 × 10 cm. All flaps survived after second stage. Varied degrees of venous congestion were observed after flap insets in all cases but none required any further treatment for the congestion. The entire lesion could not be resected due to the large size of the lesion in all patients. CONCLUSION: Two stage prelaminated temporoparietal fascia flap with skin graft is an effective technique for the reconstruction of partial facial defects in selected patients. It is simple, quick, safe and reliable, and requires no expansion of skin or no microsurgery.

Effect of acute nitrate and citrulline supplementation on muscle microvascular response to ischemia-reperfusion in healthy humans.

Nitric oxide (NO) is implicated in vasomotor control mechanisms altering the diameter of the vessels under various physiological and pathological conditions. There are 2 main NO production pathways, 1 NO synthase (NOS) independent (nitrate-nitrite-NO) and the other is NOS dependent (citrulline-arginine-NO). The objective of the study was to evaluate the effect of acute nitrate and citrulline supplementation on post-ischemic vascular response in healthy subjects. Fourteen subjects performed 2-leg vascular occlusion tests, 3 days apart. They were randomly assigned to consume a drink containing 1200 mg (19.4 mmol) of nitrate and 6 g of citrulline (N+C) or a placebo (Pl). Changes in total hemoglobin (Hbtot) and oxyhemoglobin (HbO2) concentrations were recorded by near-infrared spectroscopy on the thigh and calf muscles. No differences between N+C and Pl were observed during the ischemic period. Hbtot increased to a larger extent during the reperfusion period for the thigh (e.g., area under the curve, 821 ± 324 vs. 627 ± 381 mmol·s-1, p = 0.003) and the calf (515 ± 285 vs. 400 ± 275 mmol·s-1, p = 0.029) in the N+C versus Pl conditions. Similar results were found regarding HbO2 for the thigh (e.g., area under the curve, 842 ± 502 vs. 770 ± 491 mmol·s-1, p = 0.077) and the calf (968 ± 536 vs. 865 ± 275 mmol·s-1, p = 0.075). The larger postocclusive Hbtot and HbO2 responses observed after N+C intake suggests a greater post-ischemic vasodilation, which may be due to increased NO availability, via the activation of the 2 main NO production pathways.