Local Tissue Edema Research Articles

Combination Administration of Heparin and Nitroglycerin for the Treatment of Polycaprolactone-Induced Intravascular Embolism: A Preclinical Investigation.

As a new-generation collagen stimulator, polycaprolactone (PCL) containing filler has been extensively applied in facial dermal fillers and other medical aesthetic fields. However, inadvertent intravascular injection of PCL may result in complications such as tissue edema, flap necrosis, and even blindness. To date, there is no effective treatment for PCL-induced intravascular embolism. The aim of this study was to identify a viable resolution for the embolism resulting from intravascular administration of PCL-containing fillers. Two different animal experiments were performed: (1) PCL-induced rat inferior epigastric arteries embolism, followed by gross observation, histological evaluation, and cytokines analysis from serum; and (2) PCL-induced rabbit auricular artery embolism, immediately treated with heparin and nitroglycerin. The ears were then evaluated by gross observation, Laser speckle imaging, in vivo imaging system (IVIS) imaging, and histological evaluation. Saline and hyaluronic acids (HA) were used as controls, hyaluronidase was used as a positive drug. In a rat model of inferior epigastric arteries embolism, both intravascular injection of HA and PCL resulted in flap necrosis, indicating that the filler-induced intravascular embolism can lead to serious complications. In a rabbit model of auricular artery embolism, the combination treatment of heparin and nitroglycerin resulted in a relative blood reperfusion recovery of 80% in the ischemic area of the PCL group on day 7 post-operation, which was comparable to that of the HA group treated with hyaluronidase. Histological analysis revealed that the administration of heparin and nitroglycerin significantly attenuated intravascular thrombosis formation and inflammatory cell aggregation. The combination of heparin and nitroglycerin effectively restores blood flow reperfusion in the intravascular embolization caused by PCL filler injection, alleviates local tissue edema and flap necrosis. These findings offer a novel approach for future clinical management of intravascular embolization with PCL-containing filler injection. This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Critical Upper Airway Edema After a Bee Sting to the Uvula

Hymenoptera stings of the upper airway are rare events, but can result in rapid, life-threatening airway emergencies. The allergenic and toxic mediators that are released from the stings of bees, wasps, and hornets can cause local tissue inflammation and edema with subsequent upper airway obstruction. We report the case of a 15-y-old girl who suffered a bee sting to the uvula while zip-lining in Costa Rica. Shortly thereafter, she developed a choking sensation with associated dysphonia, odynophagia, drooling, and respiratory distress. She was brought to a rural emergency medical clinic where she was noted to have an erythematous, edematous, boggy uvula, with a black stinger lodged within it, as well as edema of the anterior pillars of the tonsils and soft palate. The stinger was removed with tweezers and she was treated with an intravenous corticosteroid and antihistamine. She had persistence of airway edema and symptoms until the administration of epinephrine, which resulted in clinical improvement shortly thereafter. In our review of this case and the existing literature, we emphasize the importance of early recognition and management of hymenoptera stings of the upper airway, which should always include immediate manual removal of the stinger, and in cases with significant upper airway edema, the administration of epinephrine should be considered.

An Investigation of Vascular Endothelial Growth Factor (VEGFR-1 and VEGFR-2) in Burn Wound Healing.

Burn damage is a complicated trauma that causes local and general tissue edema as a result of cell breakage and capillary leak syndrome. Angiogenesis plays a key part in the mechanisms that are initiated by tissue damage (e.g., burns) since it works directly and precisely on endothelial cells. The primary mediators of angiogenesis are vascular endothelial growth factor (VEGF) and its receptors (VEGFR-1 and VEGFR-2). This study aimed to figure out what functions VEGF and its receptors play in wound healing after burn, and the systemic release of VEGF in people following severe burn damage. This study included 23 burnt adult serum and 20 healthy controls. The enzyme-linked immunosorbent test was used to assess circulating VEGF serum levels and its receptors (VEGFR-1 and VEGFR-2). VEGF serum levels were considerably higher in this study, compared to VEGF levels in healthy controls. The levels of VEGFR-1 and VEGFR-2 have significantly risen; moreover, VEGF and its receptors have a significant impact on edema-related problems in severely burned individuals. Burn is a frequent disease that damages the skin and induces the production of mediators that cause neovasculaturein the majority of patients. VEGF, which causes vasculogenesis and angiogenesis, is one of the most important factors in the skin.

Protective Effect of Conditioned Media of Human Fetal Dermal Mesenchymal Stem Cells Can Inhibit Burn-induced Microvascular Hyperpermeability.

Burns often cause loss of skin barrier protection, fluid exudation, and local tissue edema, which hinder functional recovery. Effectively improving the quality of deep burn wound healing, shortening the wound healing time, and reducing tissue fluid leakage are urgent problems in the medical field. Human mesenchymal stem cells (MSCs) can effectively stabilize vascular endothelial injury. Fetal dermal MSCs (FDMSCs) are a newly discovered source of MSCs derived from the skin of accidentally aborted fetuses. However, the effect of FDMSCs on vascular permeability remains poorly understood. In this study, conditioned media from FDMSCs (F-CM) extracted from fetal skin tissue was prepared. The effect of F-CM on vascular permeability was evaluated using the internal circulation method FITC-dextran in vivo, and several in vitro assays, including cell viability assay, transwell permeability test, immunofluorescence, and western blotting. Altogether, our results demonstrate that F-CM could inhibit burn-induced microvascular hyperpermeability by increasing the protein expression levels of occludin and VE-cadherin, while restoring the expression of endothelial F-actin, and providing the foundation of a novel therapy for the treatment of burns with F-CM.

Immediate Artificial Urinary Sphincter (AUS) Reactivation at the Time of Urethral Cuff Exchange is Not Associated with Increased Erosion Rate

ObjectiveTo retrospectively evaluate the outcomes of immediate artificial urinary sphincter (AUS) reactivation in patients after urethral cuff replacement. It is common practice to delay reactivation of an AUS for four to six weeks following surgery to replace a failed urethral cuff. This is due to concerns about local tissue edema risking obstruction and concerns for urethral erosion. Despite these concerns, there are no published data to support this practice. MethodsRetrospective chart review of single surgeon procedures performed from 2005-2020. Patients with urethral cuff replacement for recurrent stress incontinence due to compression or mechanical failure were included. ResultsThirty-four patients were identified who had immediate reactivation of the AUS following urethral cuff exchange. Thirty of these patients (88.2%) had radical prostatectomy and five patients also underwent further radiation therapy (14.7%). At 6 months follow-up, there was no reported events of erosion. Likewise, 32/34 (94%) of patients had no complications and reported expected urinary function of the AUS. Urinary retention was not observed. One patient required further re-exploration for a complication within his AUS system (2.9%), and another was ultimately unsatisfied with their unchanged baseline continence despite a fully functioning AUS (2.9%). ConclusionIn this series, we observe that immediate reactivation of the AUS after urethral cuff exchange is a safe and reasonable management approach. Limitations of this analysis include a single institution, retrospective study. However, early AUS reactivation after device revision has not been reported in the literature and warrants further investigation given the impact on patient quality of life.

Is the likelihood of dysphagia different in patients undergoing one-level versus two-level anterior cervical discectomy and fusion?

BACKGROUND CONTEXTDysphagia following anterior cervical discectomy and fusion (ACDF) is a common complication, the etiology of which has not been established. Given that one potential mechanism for dysphagia is local tissue edema, it is thought that a greater number of operative levels may result in higher dysphagia rates. However, prior reports comparing one-level to two-level ACDF have shown varying results. PURPOSETo determine if there is a difference in dysphagia between one-level and two-level ACDF. STUDY DESIGN/SETTINGRetrospective review of prospectively collected data. PATIENT SAMPLEPatients who underwent one- or two-level ACDF with a plate-graft construct by a single-surgeon at a high-volume academic medical center. OUTCOME MEASURESNeck Disability Index, Visual Analog Scale for neck pain and arm pain, Short Form-12 physical and mental health components, and Swallowing Quality of Life (SWAL-QOL) Questionnaire. METHODSPatient demographics, operative data, and patient-reported outcome measures (PROMs; Neck Disability Index, Visual Analog Scale, Short Form-12, and SWAL-QOL) of patients undergoing one- and two-level ACDF were compared using Fisher exact test for categorical variables and Student's t test for continuous variables. Regression analyses were conducted to identify factors associated with 6- and 12-week SWAL-QOL scores in order to determine whether the number of surgical levels impacts these outcomes. RESULTSFifty-eight patients (22 one-level and 36 two-level ACDF) were included. Patients undergoing two-level fusions were older (54.17+8.67 vs 48.06+10.68 years, p=.02) and had longer operative times (69.08+10.51 vs 53.5+14.35 minutes, p<.0001). There were no other significant differences in demographics or operative data. Both groups showed a statistically significant improvement in PROMs from preoperatively to 12 weeks. There was no difference in PROMs or dysphagia rates between groups at any time-point. Younger age (p=.023), male sex (p=.021), longer operative times (p=.068), and worse preoperative SWAL-QOL (p<.0001) were associated with dysphagia at 6 weeks. Preoperative SWAL-QOL was the only variable associated with dysphagia at 12 weeks (p=.003). Operative time of >61.5 minutes had a sensitivity and specificity of 62.1% for worse dysphagia scores at 6 weeks compared with baseline. CONCLUSIONSThe results of our study indicate that there is no difference in the degree of postoperative dysphagia in one- versus two-level ACDF. However, other variables associated with increased postoperative dysphagia in our population included younger age, male sex, procedural time >61.5 minutes, and worse preoperative dysphagia. Larger studies are required to confirm these findings and identify additional risk factors for postoperative dysphagia.

A randomized controlled trial comparing low cost vacuum assisted dressings and conventional dressing methods in the management of diabetic foot ulcers

Background: Diabetic foot ulcers are chronic wounds which are difficult to heal, due to ischemia and intrinsic defects in angiogenesis and impaired immunity against infection. VAC therapy influences positive mechanical forces on the growth of tissues, especially in stimulating cell migration and mitosis, optimizes blood flow, decreases local tissue edema from the wound bed and provides an occlusive environment for wound healing under moist, clean and sterile conditions. Aims and objective was to compare the effectiveness of low cost hospital made VAC dressing with conventional dressings in healing of diabetic foot ulcers.Methods: This study was a prospective, randomized controlled trial and included 60 patients with diabetic foot ulcers admitted over 3 months. Patients were randomly allocated to two groups: odd numbered patients to VAC therapy and the even numbered patients to conventional dressings. Wound swab was taken before the start of the study. The data was analyzed and presented in percentages or proportions using Chi-square test and Student-t-test wherever applicable. Results: In this study it was found that in the VAC dressing group 76.7% of the ulcers had red granulation tissue at the end of therapy compared to 46.7% in conventional group. The mean wound bed preparation time was found to be 15.60 days in the conventional dressing group and 8.50 days in the VAC therapy group. In the VAC group 72.73% ulcers had no bacteria at the end of therapy.Conclusion: In this study, it was found that Vacuum Assisted Closure therapy was more effective than conventional dressings in the wound bed preparation of diabetic foot ulcers.

Molecular Imaging of Activated Platelets Allows the Detection of Pulmonary Embolism with Magnetic Resonance Imaging.

Early and reliable detection of pulmonary embolism (PE) is critical for improving patient morbidity and mortality. The desire for low-threshold screening for pulmonary embolism is contradicted by unfavorable radiation of currently used computed tomography or nuclear techniques, while standard magnetic resonance imaging still struggles to provide sufficient diagnostic sensitivity in the lung. In this study we evaluate a molecular-targeted contrast agent against activated platelets for non-invasive detection of murine pulmonary thromboembolism using magnetic resonance imaging. By intravenous injection of human thrombin, pulmonary thromboembolism were consistently induced as confirmed by immunohistochemistry of the lung. Magnetic resonance imaging after thrombin injection showed local tissue edema in weighted images which co-localized with the histological presence of pulmonary thromboembolism. Furthermore, injection of a functionalized contrast agent targeting activated platelets provided sensitive evidence of focal accumulation of activated platelets within the edematous area, which, ex vivo, correlated well with the size of the pulmonary embolism. In summary, we here show delivery and specific binding of a functionalized molecular contrast agent against activated platelets for targeting pulmonary thromboembolism. Going forward, molecular imaging may provide new opportunities to increase sensitivity of magnetic resonance imaging for detection of pulmonary embolism.

Sialolithiasis

Clinical Image: A 76 year old african american female presented with left submandibular swelling that had been sharply increasing in size for 4 days. The patient complained of pain with swallowing. The physical examination was remarkable except for large swelling of the left side of the neck and a left sublingual hard nodule. The neck mass was firm, indurated, non-mobile, and tender. Computed tomography revealed calcifications in the left sublingual area and the swelling to be local tissue edema. A diagnosis of Sialolithiasis was made. Given the patient’s presentation and history. Sour lemon drops, warm compresses, and massage of the neck mass caused exudation of multiple different size stones from whartons duct. Less than 2% of stones arise from the sublingual gland.

Increased Tissue Pressure Induces Demyelinated Lesions and Necroses in the Brain

A general brain edema increases the size of the brain tissue and stretches the elastic neuronal and glial fibers. Myelinated fibers are more elastic than unmyelinated fibers. The stretching of the neuronal fibers leads particular in regions of the white matter or areas surrounded by myelinated fiber tracts to an increased tissue pressure. This physical principle can be the reason for demyelination and tissue necrosis. The higher the tissue pressure, the lower the blood perfusion. We support the pressure-hypothesis by comparison with well-known pressure related pathologies of the nervous system and other organs. One convincing example is the central pontine myelinolysis. A general or local tissue edema may lead especially in the periventricular and the deep white matter, but also in the cerebellum, the brain stem and the spinal cord to the formation of hypoxemic lesions. In consequence, this could result in diseases like leukoaraiosis, Binswanger encephalopathy, idiopathic intracranial hypertension and Multiple Sclerosis (MS). In cases of brain tissue swelling, capsula-like structures may lead to a rapid increase in tissue pressure within the enclosed areas. This may occur particularly at the optic nerve. A reduced reabsorption of Cerebrospinal Fluid (CSF) can also lead to an increase of the pressure in the Central Nervous System (CNS).

Spontaneous Perforation of the Esophagus in a Patient With Achalasia

Esophageal perforation in achalasia is rare. The risk would mainly follow pneumatic dilatation, and spontaneous perforation has not been described. We report a case of spontaneous rupture of the midesophagus in a 56-year-old woman with treated achalasia in whom the perforation occurred during a meal and was not preceded by emesis. A gastrografin swallow confirmed extravasation of contrast medium from the esophagus, and endoscopy revealed significant esophageal food stasis, consistent with achalasia, with a large tear in the midesophagus and gross mediastinal contamination. She subsequently underwent a three-stage esophagectomy with an uneventful recovery.

The role of leukotrienes in immunopathogenesis of rheumatoid arthritis.

Rheumatoid arthritis (RA) is a chronic inflammatory disorder of joints for which there is no strict cure. However, conventional medications can reduce inflammation, relieve pain, and slow joint damage. Leukotrienes are a family of paracrine agents derived from oxidative metabolism of arachidonic acid. Synthesis of lipid mediators and subsequent induction of receptor activity are tightly regulated under normal physiological conditions, so that enzyme and/or receptor dysfunction can lead to a variety of clinical signs and symptoms of disease, such as local pain and tissue edema. In these tissues, immunocompetent cells accumulate at the site of injury, contributing to tissue damage and perpetuation of the disease process. Leukotrienes (often leukotrieneB4) as potent chemotactic agents can provoke most signs and symptoms in rheumatoid arthritis by initiating, coordinating, sustaining, and amplifying the inflammatory response, through recruitment of leukocytes. A number of studies have reported that pharmacological modulation in this field can significantly attenuate clinical manifestations associated with different inflammatory pathologies.

Zebrafish (Danio rerio) as a Screen for Attenuation of Lancefield Group C Streptococci and a Model for Streptococcal Pathogenesis

Group C streptococci are highly contagious pyogenic bacteria responsible for respiratory tract, lymph node, urogenital tract, and wound infections. Wild-type strains of Streptococcus equi ssp equi (S. equi) and Streptococcus equi ssp zooepidemicus (S. zoo) as well as a commercially available modified live vaccine strain of S. equi were evaluated for virulence in zebrafish. Survival times, histologic lesions, and relative gene expression were compared among groups. Based on the intramuscular route of infection, significantly shorter survival times were observed in fish infected with wild-type strain when compared to modified live vaccine and S. zoo strains. Histologically, S. zoo-infected fish demonstrated a marked increase in inflammatory infiltrates (predominantly macrophages) at the site of infection, as well as increased cellularity in the spleen and renal interstitium. In contrast, minimal cellular immune response was observed in S. equi-injected fish with local tissue necrosis and edema predominating. Based on whole comparative genomic hybridization, increased transcription of positive acute-phase proteins, coagulation factors, and antimicrobial peptides were observed in S. equi-injected fish relative to S. zoo-injected fish, while mediators of cellular inflammation, including CXC chemokines and granulin, were upregulated in S. zoo-injected fish relative to S. equi-injected fish. In a screen of 11 clinical isolates, S. equi strains with a single nucleotide deletion in the upstream region of szp, a known virulence factor of streptococci, were found to be significantly attenuated in zebrafish. These collective findings underscore the value of the zebrafish as a model of streptococcal pathogenesis.

The Histamine Reaction: A Useful Adjunct for Monitoring Free Flaps

Sir: Regular observation in the immediate postoperative period following free tissue transfer is imperative to flap survival.1–4 Free flaps are most vulnerable until the reepithelialization of the anastomosis.2,3 Clinical vigilance and careful monitoring are essential during this period to ensure successful outcomes. Survival rates of greater than 50 percent can be expected in salvaged flaps, with survival being inversely proportional to both the delay in detecting compromised perfusion and the subsequent delay in surgical exploration.1–5 Flap monitoring is therefore a crucial prerequisite to successful flap salvage. A commonly used method of monitoring is capillary refill measurement, which involves digital pressure on the skin for 3 seconds and then release. The skin blanches temporarily but returns to normal skin color within 2 seconds. A prolonged capillary refill time indicates inadequate flap perfusion, whereas a brisk return may represent compromised venous drainage of the flap.2,3,5 However, assessment of capillary return in, for example, perforator flaps can be challenging on account of the difficulty of eliciting a blanching response on application of digital pressure because of paleness of flaps. Histamine and serotonin are the primary mediators released in inflammatory reactions. These preformed mediators are found in mast cells, basophils, and platelets, and their release leads to an increase in vascular permeability, resulting in local tissue edema. The senior author (M.S.K.) often induces a histamine flare onto the cutaneous surface of pale free flaps postoperatively (Fig. 1). Typically, this is achieved by gently scratching the surface of the flap with a handle of a pair of Adson's forceps. This mechanical irritation of the epidermis results in histaminergic activation with local angioedema characterized by a wheal and flare.4 This flare can be used as a landmark to subsequently assess capillary refill. Histamine is directly released from cutaneous mast cells in response to mechanical stimuli, although eicosanoids, in addition to other cytokines, may also have a role to play in this immunoglobulin E–mediated process.Fig. 1.: (Above, left) Free flap before scratch test. The flap perfusion status is difficult to determine accurately, as the flap is pale. (Above, right) Primed flap following scratch. A transverse strip of hyperemic skin is visible along the flap. (Below, left) Assessment of capillary refill of primed free flap by gentle compression with the handle of a pair of tenotomy scissors. (Below, right) A blanched area corresponding to the scissors handle is readily visible, thus allowing an accurate assessment of the capillary refill time.The authors propose the histamine reaction scratch test to surmount the assessment difficulties of pale flaps. This method of augmenting the innate capillary return greatly improves the ability to undertake accurate flap observations in pale free flaps. The limitation to the histamine scratch test is its duration of action, which we estimate to be on the order of 2 to 6 hours. The test can be readily repeated at the bedside until the flap observation period has ceased. It is common practice to assess flap perfusion by using a hypodermic needle to scratch or prick the cutaneous portion of the flap to induce capillary bleeding; indeed, in certain situations, such as head and neck reconstruction, a small portion of the flap may be deepithelialized to facilitate direct observation of capillary bleeding on repeated occasions. We have used these techniques in our unit; however, we are cognizant of the attendant risks of infection, hematoma formation, and potential iatrogenic injury to the pedicle itself. The histamine scratch test all but obviates these risks, as the epidermis is not breached. This response occurs independently of the sympathetic and parasympathetic nervous systems. We have shown that scratching a pale flap is a good, reliable, and safe way of monitoring a free flap. Although physiologically this assessment works in clinical practice, the response does not last long enough for the flap to be monitored for sustained periods of time. Assessment of capillary return in pale flaps (such as the deep inferior epigastric perforator and anterolateral thigh flaps) can be problematic on account of the difficulty of eliciting a blanching response on application of digital pressure. The authors feel that this test is a technically straightforward, noninvasive, bedside test that aids in informing the clinician of the underlying flap perfusion status. The test is therefore an invaluable adjunct in the monitoring of pale free flaps. Zeeshan Ahmad, M.R.C.S. Marc C. Swan, D.Phil. Department of Plastic and Reconstructive Surgery and Burns Matthew Flynn, F.R.C.Path. Department of Histopathology Mansoor S. Khan, F.R.C.S.(Plast.) Department of Plastic and Reconstructive Surgery and Burns Salisbury District Hospital Salisbury, Wiltshire, United Kingdom DISCLOSURE No funding was received in the production of this article. There is no conflict of interest.

Hematologic Abnormalities Following Crotaline Snakebites In South Carolina

AbstractAbstract 4753 Background:Pit viper envenomation causes local tissue edema, pain, and ecchymosis. In certain geographical areas of the United States thrombocytopenia, hypofibrinogenemia and coagulopathy are common hematological abnormalities, and ones that dictate both a reason for treatment with antivenom as well as an important monitor of therapeutic efficacy. Data on the frequency and severity of hematological abnormalities following envenomation by crotaline species in South Carolina has not been reported. We evaluated clinical and hematologic laboratory findings and treatment course following copperhead and rattlesnake bites in South Carolina. Method:We conducted a retrospective evaluation of all copperhead and rattlesnake bites reported to the Palmetto Poison Center from April 2005 through June 2010. Severity of the snakebite and development of hematologic toxicity associated with envenomation cases were documented before and after crotaline Fab antivenom (CroFab®) administration. Adverse events associated with antivenom therapy, recurrence phenomena, delayed onset of symptoms, and performance of fasciotomy were also recorded. Results:Overall, 194 crotaline snakebites were identified- 156 copperhead bites and 38 rattlesnake bites. Males accounted for 75% of copperhead bite patients (median age, 36 years; 51% with bites on upper extremities) and 82% of rattlesnake bite patients (median age, 42.5 years; 76% on upper extremities). All patients except one were treated at a healthcare facility with > 80% arriving within 6 hours following the bite. Over 60% of patients received crotaline Fab antivenom; no patients received the older Antivenin Crotalidae Polyvalent. Severity of the envenomation for copperheads and rattlesnakes was classified as dry (7.74%, 13.16%), mild (68.39%, 73.68%), moderate (22.58%, 10.53%), and severe (1.39%, 2.63%), respectively. Seventeen of 156 patients (10.89%) developed abnormal hematologic laboratory results following copperhead bites and two of 38 (5.26%) patients developed abnormal hematologic laboratory parameters with rattlesnake bites. Of these, the most common abnormality was coagulopathy (16/17 = 94.11%; 2/2 = 100%), followed by hypofibrinogenemia (5/17 = 29.41%; 0/0 = 0.00%) and thrombocytopenia (2/17 = 11.76%; 0/0 = 0.00%) for copperheads and rattlesnakes respectively. Recurrence phenomena was observed in 4 patients with copperhead bites and 2 patients with rattlesnake bites, while delayed onset of symptoms were seen in 12 patients and 5 patients, respectively. Among those experiencing recurrence, 75% of patients bitten by copperheads experienced local effects including pain and swelling and 25% experienced coagulopathy, while a 100% of the patients bitten by rattlesnakes experienced recurrent local effects. Among those experiencing a delayed onset of symptoms, 90% of the patients with copperhead bites experienced coagulopathy while 10% had local effects and 100% of the patients bitten by rattlesnakes experienced coagulopathy. Reaction to the antivenom developed in three patients. Three patients underwent a fasciotomy. Conclusions:Antivenom therapy is typically administered to halt the progression of local envenomation effects and improve abnormal hematologic parameters towards normal. In South Carolina, the primary indication for antivenom treatment is most commonly to treat local clinical findings. Our poison center experience suggests coagulopathy is the most common hematologic laboratory abnormality following crotaline envenomation in addition to a low rate of thrombocytopenia in our geographic location. Other geographic areas of the United States are recognized to have more frequent and severe hematologic complications following crotaline bites. Disclosures:Bennett:Pfizer: Consultancy.

The role of topical negative pressure in wound repair: Expression of biochemical markers in wound fluid during wound healing

The clinical effects of topical negative pressure therapy (TNP) on wound healing are well described in numerous articles. While the mechanism(s) of action are not completely understood, it is postulated that reduction of local and interstitial tissue edema, increased perfusion of the (peri-) wound area, changed bacterial composition, and mechanical stimulation of the woundbed contribute to the clinical success. Our hypothesis is that with the removal of excessive fluid, proteolytic enzymes negatively influencing the healing process are removed. Our aim was to assess whether the concentrations of albumin, matrixmetalloproteinase-9 (MMP-9), and tissue inhibitor of metalloproteinase (TIMP-1) were different between wounds treated with TNP and conventional gauze therapy. We analyzed wound fluid samples of 33 wounds treated with either TNP therapy (n=15) or conventional therapy (n=18) on albumin, pro- and activated MMP-9, TIMP-1, and the ratio of total MMP-9/TIMP-1. Albumin levels were found to increase significantly in acute wounds compared with chronic wounds; however, no difference could be found on comparing TNP with conventional therapy. We did find significantly lower levels of pro-MMP-9 and lower total MMP-9/TIMP-1 ratio in TNP-treated wounds during the follow-up of 10 days. These data strongly suggest that TNP therapy influences the microenvironment of the wound.

Lower extremity compartment syndrome after off-pump aortocoronary bypass

Lower extremity compartment syndrome after off-pump aortocoronary bypass

Dielectric Measurement in Experimental Burns: A New Tool for Burn Depth Determination?

There has been a lack of methods to provide quantitative information of local tissue edema after burn injury. Noninvasive dielectric measurements provide this information. The measured value, the dielectric constant, is directly related to the amount of water in tissue. Using probes of different sizes, the measurements give information from different tissue depths. The aim of this study was to characterize edema formation at different tissue depths and to examine whether the dielectric measurements could be used to distinguish partial- and full-thickness burns in pigs. An experimental animal study with pigs (n = 6) was performed in which dielectric measurements were taken of superficial, partial-thickness, and full-thickness burns for 72 hours. There was an increase in tissue water content in the superficial dermis in the partial-thickness burns at 48 hours. In whole dermis, the superficial burns resulted in increased tissue water content at 8 hours, and the partial-thickness burns resulted in increased tissue water content at 8, 24, and 72 hours. In deep burns, the water content was significantly decreased in the superficial dermis at 24 hours. All burns resulted in a considerable increase in fat water content. The dielectric probes could be used to differentiate partial- and full-thickness burns as early as 8 hours after burn. Receiver operating curve analysis of the measurements indicated 70 to 90 percent sensitivity and 80 to 100 percent specificity after 8 hours. The dielectric measurements provide a sensitive and noninvasive method for examining tissue edema and differentiate partial- and full-thickness burns in experimental burns. Thus, they are of clinical interest for early burn depth determination.

Experimental study of bioabsorbable rod and calcium phosphate cement intramedullary fixation system in rabbit femoral shaft fractures

目的 研究自增强型可吸收棒(PDLLA)联合磷酸钙骨水泥(CPC)髓内固定管状骨骨折的可行性,为用于手部掌、指骨骨折提供实验室依据.方法将自增强型可吸收棒植入兔股骨干(横形骨折)髓腔内,两端用磷酸钙骨水泥粘合固定(实验组),克氏针髓内固定(对照组).术后比较两组周围组织的反应,X线片变化及力学强度.结果术后4周实验组和对照组的股骨干横向截骨均未见明显畸形,X线片示实验组的骨痂量多于对照组;测定股骨三点弯曲最大破坏载荷实验,结果两组无明显差异.术后8周剪切力较术后4周无下降.术后8周两组的骨折均愈合,未出现局部反应性肿胀、积液、感染及全身毒性反应.结论自增强型可吸收棒与磷酸钙骨水泥在骨内具有良好的组织相容性,两者联合应用行管状骨骨折髓内固定,效能与克氏针固定相当。

Advances in the diagnosis and treatment of ptosis

The surgical correction of blepharoptosis, both congenital and acquired, has been intensively examined and reported on for many years. This paper reviews recent publications on basic science, evaluation, technique modifications, and innovative materials in the care of ptosis patients. The frontalis suspension technique is a commonly performed surgical correction of congenital blepharoptosis, used widely in the repair of ptosis with poor levator function. The repair typically includes using either tissue such as autologous or banked fascia lata or permanent suture material. The procedure involves connecting the motor unit (frontalis muscle) and the upper eyelid. Authors have recently reintroduced the technique of a dynamic frontalis muscle flap tunneled into the eyelid that directly attaches to the tarsal plate.Patients presenting with symptomatic blepharoptosis due to disinsertion or thinning of the levator aponeurosis require surgical repair. Multiple groups have tended toward a minimally invasive approach directed specifically at the levator aponeurotic defect. Proposed advantages of a small eyelid incision (8-13 mm) include less local anesthetic and tissue distortion, less ecchymosis and edema, decreased operative times, a shortened recovery period, and improved surgical results. Surgical correction of congenital blepharoptosis may be performed with autologous fascia lata, cadaveric allograft, or permanent suture material. The use of a frontalis muscle advancement flap is elegantly designed; however, its role in clinical practice remains to be defined. Advancement of the levator aponeurosis for senile blepharoptosis may be preformed via a minimally invasive small incision approach. Patients benefit with decreased operative time, edema, ecchymosis, and recovery times.