Excellent Hemostatic Properties Research Articles

Biosynthetic calcium-doped biosilica with multiple hemostatic properties for hemorrhage control.

In this study, we reported calcium-doped biosilica (Ca-biosilica) with multiple hemostatic properties derived from Coscinodiscus sp. frustule. The incorporation of calcium into the diatom frustule was achieved by a simple biosynthetic route through feeding the diatoms with calcium chloride, which was confirmed by calcein staining and EDXS. Ca-Biosilica exhibited an efficient water absorption ratio (36.36 ± 1.44 times its own weight of liquid), superior compatibility (hemolysis ratio <5%, no cytotoxicity against MEFs) and excellent hemostatic effect (203.67 ± 15.63 s at 5 mg mL-1; 145.01 ± 20.41 s at 10 mg mL-1). The intrinsic blood coagulation pathway was clearly strengthened by the unique interface of Ca-biosilica, which was rich in silanol groups and calcium, leading to fast hemorrhage control in rat-tail amputation model. The clotting time of Ca-biosilica was 88.34 ± 28.54 s, which was similar to that of Quickclot® zeolite, whereas only one-third blood loss by weight (0.21 ± 0.16 g) was found in Ca-biosilica-treated group compared with that of the Quickclot® zeolite group (0.63 ± 0.09 g). The results prove that Ca-biosilica is promising as a quick hemostatic agent due to its effectiveness, excellent biocompatibility and simple and environmentally friendly preparation process.

Preparation, Characterization and Properties of Alginate/Poly(γ-glutamic acid) Composite Microparticles.

Alginate (Alg) is a renewable polymer with excellent hemostatic properties and biocapability and is widely used for hemostatic wound dressing. However, the swelling properties of alginate-based wound dressings need to be promoted to meet the requirements of wider application. Poly(γ-glutamic acid) (PGA) is a natural polymer with high hydrophility. In the current study, novel Alg/PGA composite microparticles with double network structure were prepared by the emulsification/internal gelation method. It was found from the structure characterization that a double network structure was formed in the composite microparticles due to the ion chelation interaction between Ca2+ and the carboxylate groups of Alg and PGA and the electrostatic interaction between the secondary amine group of PGA and the carboxylate groups of Alg and PGA. The swelling behavior of the composite microparticles was significantly improved due to the high hydrophility of PGA. Influences of the preparing conditions on the swelling behavior of the composites were investigated. The porous microparticles could be formed while compositing of PGA. Thermal stability was studied by thermogravimetric analysis method. Moreover, in vitro cytocompatibility test of microparticles exhibited good biocompatibility with L929 cells. All results indicated that such Alg/PGA composite microparticles are a promising candidate in the field of wound dressing for hemostasis or rapid removal of exudates.

Influences of mesoporous zinc-calcium silicate on water absorption, degradability, antibacterial efficacy, hemostatic performances and cell viability to microporous starch based hemostat

Efficacious hemostatic agents have significant potential application in visceral organ or large vessel arterial injure. In this study, mesoporous zinc-calcium silicate (m-ZCS) was synthesized, and microporous starch (MS) based hemostatic agents of m-ZCS/MS composites for hemorrhage control was fabricated. The results showed that the incorporation of m-ZCS into MS significantly enhanced the water absorption and degradability of the composites, which were dependent on the m-ZCS content. Moreover, the composites with antibacterial property could inhibit the growth of Escherichia coli (E. coli) and the antibacterial ratios increased with the m-ZCS content. The in vitro coagulation evaluation by using activated partial thromboplastin time (APTT) and prothrombin time (PT) revealed that the composites significantly activated the intrinsic and extrinsic pathway of coagulation cascade. In addition, for the animal model of rabbits in ear vein, skin, arterial and liver injuries, the hemostatic time of the composites obviously reduced with the increase of m-ZSC content, in which the composite with 15wt% m-ZCS content (15mZSC) showed remarkable efficacy on bleeding control. The composites could promote the viability of L929 cells, indicating no cytotoxicity of the composites. The results suggested that the m-ZCS/MS composites with excellent hemostatic and antibacterial properties might be a candidate for controlling bleeding and infection.

Functional improvement of hemostatic dressing by addition of recombinant batroxobin.

Despite the excellent hemostatic properties of collagen and chitosan pads, they reported to brittle behavior and lack sufficient hemostatic effect within relevant time. Therefore, we created a novel pad using collagen and chitosan with recombinant batroxobin (r-Bat). r-Bat acts as a thrombin-like enzyme in the coagulation cascade. Specifically, r-Bat, in contrast to thrombin, only splits fibrinopeptide A off and does not influence other hemostatic factors or cells, which makes it clinically useful as a stable hemostatic agent. Also the materials in the pad have synergetic effect because they have different hemostatic mechanisms in the coagulation cascade. This report propose the novel hemostatic pad isreasonable that a great potential for excessive bleeding injury and improve effects of natural substance hemostatic pad.

In situ thiolated alginate hydrogel: Instant formation and its application in hemostasis.

An in situ formed hydrogel was synthesized by sodium alginate and cysteine methyl ester, which turned the sodium alginate into thiolated alginate (SA-SH). SA-SH can in situ formed into hydrogel (SA-SS-SA) with a large amount of water through covalent bond in less than 20 s. The structure characterization showed that the mechanism of SA-SH gelation was thiol-disulfide transformation. The rheology and cytotoxicity experiments of SA-SS-SA hydrogel were also investigated, which indicated that SA-SS-SA hydrogel had an appropriate mechanical strength as well as an excellent biocompatibility. The SA-SS-SA hydrogel would degrade under certain conditions after a few days and its mechanism was disulfide alkaline reduction. Finally, the hemostatic property of SA-SH was tested by rat tail amputation experiment. The time to hemostasis of rat reduced from 8.26 min to 3.24 min, which proved that SA-SH had an excellent hemostatic property.

Treatment of Severe Aortic Bleeding Using Hemopatch in Swine on Dual Antiplatelet Therapy

ABSTRACTPurpose: The perioperative management of patients on antithrombotic therapy is currently an unresolved problem as these therapies pose a considerable risk for perioperative hemorrhagic complications. The presented studies investigated the efficacy of a new collagen technology to achieve hemostasis. A polyethylene glycol-coated collagen pad (PCC) was compared to a marketed fibrinogen-thrombin coated collagen pad (FTC) for the treatment of an aortotomy incision in heparinized swine on dual antiplatelet therapy. Materials and Methods: Twenty-eight 3-mm aortotomy incisions were created in nine heparinized pigs without antiplatelet therapy and treated with PCC. Sixty-eight aortotomy incisions were created in ten heparinized pigs that received clopidogrel (10–11 mg/kg) and acetylsalicylic acid (8–11 mg/kg) orally for 5 days, and treated with either PCC or FTC (N = 34/group). Dual antiplatelet therapy resulted in significantly reduced platelet function. Aortotomy incisions resulted in life-threatening bleeding of 35–292 ml/min. Results: In animals without antiplatelet treatment, PCC provided 96% immediate hemostatic success. In animals with antiplatelet treatment, FTC provided 18% immediate hemostatic success increasing to 74% after 10 min. Strikingly, PCC provided 94% immediate success increasing to 100% after 10 min. Controlling for differences in pretreatment bleeding rates, statistical model-estimated time to hemostasis was 12 times shorter in PCC-treated lesions (p < .02). Conclusion: The combination of a procoagulant collagen pad with a synthetic sealing component provides excellent hemostatic properties under a worst-case scenario. PCC rapidly and firmly adheres to tissue, thereby controlling severe arterial bleeding, even when platelet function is significantly reduced. Treatment with PCC provided superior time to hemostasis compared to FTC.

Preparation of porous carboxymethyl chitosan grafted poly (acrylic acid) superabsorbent by solvent precipitation and its application as a hemostatic wound dressing

The volume phase transition of a hydrogel initiated by shrinking may result in complex patterns on its surface. Based on this unique property of hydrogel, we have developed a novel solvent precipitation method to prepare a kind of novel superabsorbent polymers with excellent hemostatic properties. A porous carboxymethyl chitosan grafted poly (acrylic acid) (CMCTS-g-PAA) superabsorbent polymer was prepared by precipitating CMCTS-g-PAA hydrogel with ethanol. Its potential application in hemostatic wound dressing was investigated. The results indicate that the modified superabsorbent polymer is non-cytotoxic. It showed a high swelling capacity and better hemostatic performance in the treatments of hemorrhage model of ear artery, arteria cruralis and spleen of the New Zealand white rabbit than the unmodified polymer and other commonly used clinic wound dressings. The hemostatic mechanism of the porous CMCTS-g-PAA polymer was also discussed.

Biosynthesis, characterization, and hemostasis potential of tailor-made poly(3-hydroxybutyrate-co-3-hydroxyvalerate) produced by Haloferax mediterranei.

We report the biosynthesis of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) random copolymers (R-PHBV) or higher-order copolymers (O-PHBV) in Haloferax mediterranei, with adjustable 3-hydroxyvalerate (3HV) incorporation by cofeeding valerate with glucose. Their microchemical structure, molecular weight and its distribution, and thermal and mechanical properties were characterized by NMR, GPC, DSC, TGA, and universal testing machine, respectively. (13)C NMR studies showed that O-PHBV copolymers consisted of short segments of PHB and PHV covalently linked together with random PHBV segments. Consistently, two Tg were observed in the DSC curves of O-PHBV. The "blocky" feature of O-PHBV enhanced crystallinity percentages and improved Young's modulus. Notably, the film of one O-PHBV copolymer, O-PHBV-1, showed unique foveolar cluster-like surface morphology with high hydrophobicity and roughness, as characterized using static contact angle and SEM and AFM analyses. It also exhibited increased platelet adhesion and accelerated blood clotting. The excellent hemostatic properties endow this copolymer with great potential in wound healing.

Photoselective Vaporesection of the Prostate with a Front-firing Lithium Triborate Laser: Surgical Technique and Experience After 215 Procedures

BackgroudAlthough photoselective vaporization of the prostate (PVP) is considered one of the most promising alternatives to transurethral radical prostatectomy, a longer operative time, an unsatisfactory tissue removal rate, and the absence of postoperative pathology samples remain the main criticisms for this procedure. ObjectiveTo describe the novel technique of photoselective vaporesection of the prostate (PVRP) with a front-firing lithium triborate (LBO) laser and to report our initial experience. Design, setting, and participantsThis is a prospective study of 215 patients undergoing PVRP between November 2011 and March 2013. Their average age, prostate size, and International Prostate Symptom Score (IPSS) were 70.3±7.3 yr, 70.4±34.0ml, and 24.9±5.0, respectively. Surgical procedureThe operative technique is detailed in the accompanying video. Outcome measurements and statistical analysisPerioperative data were collected. The patients were followed up at 3, 6, 12 mo after PVRP, and functional outcomes and complications were assessed. Results and limitationsThe mean operation time was 44.1±22.6min. The mean hemoglobin decrease was 0.37±0.21g/dl. The catheterization time was 23.9±15.2h and the postoperative hospital stay was 1.8±0.8 d. Significant improvements were observed in maximum flow, IPSS, and postvoid residual urine at each follow-up time point. Compared to preoperative values, prostate volume and serum prostate-specific antigen fell by 67% and 63%, respectively, at 3 mo after PVRP. No major complications were noted. Application of a hemostat for a front-firing LBO laser makes it easy to handle intractable intraoperative bleeding. The main limitation of this study is the short follow-up period. The influence of PVRP on sexual function and the learning curve remain to be evaluated. ConclusionsPVRP is a novel technique that is effective and safe for treatment of benign prostatic hyperplasia. This technique retains the excellent hemostatic property of LBO lasers and has a short operation time and a high tissue removal rate. The problem of the lack of postoperative tissue samples for PVP is also overcome in PVRP. Patient summaryWe have developed a novel technique named photoselective vaporesection of the prostate (PVRP) with a front-firing green laser. Our results show that PVRP retains the excellent hemostatic property of a green laser, but has a much shorter operation time and a higher rate of tissue removal than photoselective vaporization of the prostate (PVP). This technique also solves the problem of the lack of postoperative tissue specimens and the difficulty of handling intractable intraoperative bleeding. According to our initial results, PVRP is a novel technique superior to PVP in the treatment of benign prostatic hyperplasia.

Platelet rich fibrin versus Hemcon dental dressing following dental extraction in patients under anticoagulant therapy

ObjectivesDental extractions in heart surgery patients treated with artificial mechanical heart valves under anticoagulant oral therapy can be difficult as these patients present a significant risk for postoperative hemorrhagic complications. This study was performed to evaluate the use of Platelet Rich Fibrin (PRF) and Hemcon dental dressing (HDD) in cardiac patients taking Warfarin following dental extraction. Methods20 patients were involved in this study with an age range of 36–62 years. Patients having an International Normalized Ratio (INR) >3.5 were excluded. Extraction was performed under local anesthesia and as atraumatic as possible. Patients were allocated equally in two groups; group A: where PRF was inserted into the extraction socket, while group B: the extraction socket was packed by HDD. ResultsComplete hemostasis was achieved in all cases with no delayed bleeding. Patients in group A showed minimal pain and accelerated healing, while those in group B showed extreme to moderate pain on the first few days following extraction and retarded healing. Four patients developed alveolar osteitis. ConclusionsPRF has good antihemorrhagic properties and increases tissue healing and wound closure, thus allowing for a quick recovery without significant painful events. HDD has excellent hemostatic properties and can be used safely in such patients but with small amounts.

Successful Management of a Ruptured Mycotic Pseudoaneurysm Following Pancreas Transplantation Using Bovine Pericardial Patch: A Case Report

Arterial mycotic pseudoaneurysms are a rare complication of pancreas transplantation. Rupture results in catastrophic hemorrhage with a high risk of mortality. Definitive management is complicated by an extensive arterial defect within a contaminated surgical field. Synthetic vascular grafts often fail due to subsequent graft infection whereas primary repair often results in arterial stenosis. Arterial ligation may be required to prevent exsanguination. A 41-year-old man, type 1 diabetic with associated renal failure, underwent successful simultaneous pancreas and kidney transplantation. He presented, 9 months following transplantation, with life-threatening rectal bleeding secondary to a ruptured mycotic pseudoaneurysm. This was successfully managed with a bovine pericardial patch (BPP) repair of the arterial defect and enteric diversion following graft pancreatectomy. He remains well with no vascular insufficiency 18 months following the procedure. A ruptured mycotic pseudoaneurysm following transplantation carries a significant risk of mortality and represents a surgical challenge as conventional techniques using synthetic materials often fail due to the contaminated field. A BPP offers good handling characteristics, excellent hemostatic properties and a favorable profile of infection risk in comparison with synthetic grafts. This case highlights its use as a treatment for a post-transplantation ruptured mycotic pseudoaneurysm.

Use of a vessel sealing system versus conventional electrocautery for lung parenchymal resection: a comparison of the clinicopathological outcomes in porcine lungs

LigaSure, a vessel sealing system, has been shown to have excellent hemostatic properties; however, its use for lung parenchymal resection has been limited. We herein examined the hemostatic properties and potential for inducing histological lung injury of the LigaSure system in non-anatomic pulmonary resection to estimate the feasibility of its clinical application. Non-anatomic pulmonary wedge resections of the right cranial, middle, and caudal lobes were performed in four pigs using the LigaSure system (Group A) or electrocautery (Group B). In each resection, the resection time, blood loss, and weight of the resected lung were measured. The thermal effect on the lung tissue was examined by means of intraoperative thermography and histology. A total of 12 lung wedge resections were performed in each group. For an equivalent length of operation and weight of the resected lung parenchyma, Group A showed significantly lower blood loss and lower maximum and minimum temperatures of the lung tissue, as assessed by thermography, than Group B. The degree of thermal injury as estimated by a histological examination was lower in Group A than in Group B. Our study suggests that the LigaSure system may be superior to conventional electrocautery, indicating its clinical usefulness for non-anatomic pulmonary resection.

The safety and efficacy of aspirin intake in photoselective vaporization laser treatment of benign prostate hyperplasia

Endoscopic surgical treatment has become an option to treat benign prostate hyperplasia. We evaluated the safety and effectiveness of photoselective vaporization of the prostate (PVP) in patients. We evaluated preoperative and perioperative parameters, functional outcomes, and adverse events up to 12 months postoperatively of patients on oral anticoagulation therapy undergoing PVP, and compared the results with patients who did not take anticoagulation therapy. A total of 89 patients who received photoselective vaporization laser for benign prostate hyperplasia from May 2006 to February 2011 in our hospital were enrolled in our study. The patients were divided into two groups based on whether or not they were taking oral aspirin; 23 (25.8%) patients were taking aspirin derivatives (aspirin group), and 66 (74.2%) were not taking aspirin derivatives (control group). The mean prostate volume (58.8 mL vs 51 mL; P = 0.16) and mean energy consumption (235,268 J vs 289,793 J; P = 0.097) were comparable between the aspirin group and control group. The average postoperative results of hemoglobin were 13.4 mg/ dL for the aspirin group versus 13.9 mg/dL for the control group (P = 0.327). A significantly higher maximum flow rates and 80% improved post-void residual urine were noted during the followup. Postoperatively all variable showed significant improvement starting at month 1 of followup and remained improved for the 12 month followup. Postoperative complications were low and comparable between groups. PVP was characterized by excellent hemostatic properties and a very low intraoperative complication rate, even in the patients who were taking aspirin. On the basis of our perioperative results, we recommend PVP as a safe and effective procedure for patients with symptomatic benign prostate hyperplasia when taking an aspirin derivative.

2021 PROSPECTIVE EVALUATION OF IRRIGANT ABSORPTION DURING PURE TRANSURETHRAL BIPOLAR PLASMA VAPORIZATION OF THE PROSTATE BY EXPIRED BREATH ETHANOL MEASUREMENTS

You have accessJournal of UrologyBenign Prostatic Hyperplasia: Surgical Therapy and New Technology II1 Apr 20122021 PROSPECTIVE EVALUATION OF IRRIGANT ABSORPTION DURING PURE TRANSURETHRAL BIPOLAR PLASMA VAPORIZATION OF THE PROSTATE BY EXPIRED BREATH ETHANOL MEASUREMENTS Christian Daniel Fankhauser, Lukas John Hefermehl, Benedikt Kranzbühler, Oliver Gross, Marian Severin Wettstein, Nico Grossmann, Janine Corinne Capol, Matthias Zimmermann, Tullio Sulser, Alexander Müller, and Thomas Hermanns Christian Daniel FankhauserChristian Daniel Fankhauser Zürich, Switzerland More articles by this author , Lukas John HefermehlLukas John Hefermehl Zürich, Switzerland More articles by this author , Benedikt KranzbühlerBenedikt Kranzbühler Zürich, Switzerland More articles by this author , Oliver GrossOliver Gross Zürich, Switzerland More articles by this author , Marian Severin WettsteinMarian Severin Wettstein Zürich, Switzerland More articles by this author , Nico GrossmannNico Grossmann Zürich, Switzerland More articles by this author , Janine Corinne CapolJanine Corinne Capol Zürich, Switzerland More articles by this author , Matthias ZimmermannMatthias Zimmermann Zürich, Switzerland More articles by this author , Tullio SulserTullio Sulser Zürich, Switzerland More articles by this author , Alexander MüllerAlexander Müller Zürich, Switzerland More articles by this author , and Thomas HermannsThomas Hermanns Zürich, Switzerland More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2012.02.2184AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Transurethral bipolar plasma vaporisation (BPV) has been introduced as a minimal invasive alternative for conventional transurethral resection of the prostate (TURP). Especially high-risk patients may profit from irrigation with isotonic saline and from the excellent haemostatic properties of the so-called “mushroom electrode”. Those characteristics allow for a nearly bloodless operation and prevent the development of a TUR syndrome. However, it is unknown if irrigant absorption per se is prevented during BPV. METHODS A total of 55 consecutive patients were prospectively investigated between 07/2010 and 09/2011 during routine pure BPV using the TURIS HF system (Olympus GmbH, D). Intraoperative irrigation was performed with isotonic saline containing 1% ethanol. The breath ethanol concentration was measured every 10 min during the operation using an AlcoQuant 602 alcometer (r-Technik GmbH, D). The volume of irrigant absorbtion was then calculated from these concentrations using an established nomogram. Additionally, intraoperative changes in serum electrolyte and heamoglobin concentrations were recorded. RESULTS The median patients' age was 67 y (48-88 y) and median prostate volume was 41.4 ml (21-89 ml). The median operation time was 70 min (30-140 min) and median irrigation volume 21 l (3-39 l). A total of 9 patients (16.4%) showed a positive ethanol breath test during BPV. The median calculated fluid absorption in those patients was 230 ml (range: 50-2000 ml). Significant changes in electrolyte or haemoglobin concentrations were not detectable. Only one patient with an irrigant absorption of 2 l showed clinical symptoms in form of mild dyspnoea and agitation. The surgeons reported capsular perforation, opening of large prostatic sinuses or a deep bladder neck incision in all patients with detectable fluid absorption. CONCLUSIONS Significant fluid absorption occurs during BPV of the prostate despite the excellent haemostatic properties of the “mushroom electrode”. Isotonic saline irrigation prevents the development of a dreaded TUR-syndrome with serious serum electrolyte changes. However, absorption of large isotonic volumes can also be dangerous especially for patients with e.g. cardiac insufficiency. It is important to know that fluid absorption cannot be monitored by intraoperative electrolyte measurements. Respecting the anatomical boundaries of the prostate seems to play a major role in preventing fluid absorption during BPV. © 2012 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 187Issue 4SApril 2012Page: e815-e816 Advertisement Copyright & Permissions© 2012 by American Urological Association Education and Research, Inc.MetricsAuthor Information Christian Daniel Fankhauser Zürich, Switzerland More articles by this author Lukas John Hefermehl Zürich, Switzerland More articles by this author Benedikt Kranzbühler Zürich, Switzerland More articles by this author Oliver Gross Zürich, Switzerland More articles by this author Marian Severin Wettstein Zürich, Switzerland More articles by this author Nico Grossmann Zürich, Switzerland More articles by this author Janine Corinne Capol Zürich, Switzerland More articles by this author Matthias Zimmermann Zürich, Switzerland More articles by this author Tullio Sulser Zürich, Switzerland More articles by this author Alexander Müller Zürich, Switzerland More articles by this author Thomas Hermanns Zürich, Switzerland More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

In vivo biodegradation of new haemostatic biomaterials

Introduction . The new synthesized haemostatic biomaterial Matemo, is a protein meal produced by fractionation of human plasma. In previous studies it revealed its excellent haemostatic properties, so that it could become the best biomaterial to prefer in large surgical demolition. It also showed an excellent biocompatibility for its composition of human proteins, very similar to that of human tissues. This work now intended to study the in vivo biodegradation of this new biomaterial compared with another horse collagen-based haemostatic biomaterial (Antema) in order to find the best material to fill the empty cavities resulting after surgical resection of tumor masses. Materials and methods. For the experimental protocol the dorsal skin of each anesthetized animal was shaved, incised and two pouches were performed inside the subcutaneous tissue of the back, to introduce a specimen (1 cm2 of size) of Matemo on the left side, and on the right side the horse-collagen biomaterials (Antema). The same operation was repeated in 3 animals, and 3 other rats were used as controls and treated only with the selected anesthetic cocktail without intervention. The treated animals were killed all after 90 days from the operation. After death the dorsal skin of each animal was inspected in the two sides of implant and the samples from the skin and the subcutaneous tissues were taken in both sides of the back, to submit to the histological studies. Results The histological exams carried out in this experiment showed that at the 90th day post-implant both biomaterials were completely reabsorbed, but the sites of implantation were very different between them. In the side of the implanted Matemo the subcutaneous tissue showed a very poor infiltration of inflammatory cells, with a foreign body reaction fully resolved without proliferation of new fibrous tissue, neither dermal adhesion to the muscular plane. In the site of Antema implant, indeed, at the same dead line a significant infiltration of inflammatory cells jet persisted and much dense fibrous tissue attached the dermal plane to the underlying muscles.

Aortic Root Replacement Using a Biovalsalva Prosthesis in Comparison to a “Handsewn” Composite Bioprosthesis

The Biovalsalva aortic root prosthesis incorporates an Elan porcine stentless biological aortic valve suspended within a triple-layered vascular conduit with preformed aortic sinuses of Valsalva. This study compared implantation of the Biovalsalva prosthesis with a "handsewn" composite bioprosthetic graft (CE Perimount bovine bioprosthesis anastomosed to a gelatin-impregnated gelweave Dacron graft). Between December 2004 and January 2009, 39 patients underwent elective or urgent aortic root replacement (modified Bentall procedure with coronary button reimplantation) using a Biovalsalva (n = 21) or a handsewn bioprosthesis (n = 18) for aortic root dilatation. There was no significant difference in the preoperative variables between the two study groups including age (70.7 +/- 1.7 vs. 67.6 +/- 2.9 years, p > 0.05). There was no in-hospital mortality. Three patients in each group underwent concomitant aortic hemi-arch replacement. Patients who underwent Biovalsalva implantation had a reduced need for transfusion of blood (1.25 +/- 0.32 vs. 3.17 +/- 0.71 units, p < 0.05) and fresh frozen plasma (2.78 +/- 0.39 vs. 1.85 +/- 0.31, p < 0.05), and reduced mediastinal blood loss (416 +/- 52 vs. 583 +/- 74 mL, p < 0.05) compared to those with a handsewn bioprosthesis. Cardiopulmonary bypass time (141 +/- 6 vs. 170 +/- 17 minutes, p = NS) and aortic cross-clamp time (113 +/- 6 vs. 115 +/- 7 minutes, p = NS) were similar. Postoperative echocardiography demonstrated excellent hemodynamic function of the Biovalsalva prosthesis (mean size 25.1 +/- 0.4 mm valved conduit) with a peak pressure gradient of 26.2 +/- 1.9 mmHg and no or trivial valvular regurgitation. The Biovalsalva prosthesis should be considered for patients requiring a biological aortic root replacement. It offers an "off-the-shelf" preassembled composite biological valve conduit with excellent hemostatic and hemodynamic properties.

Complications of laser prostatectomy: a review of recent data

Laser techniques for the treatment of bladder outlet obstruction (BOO) due to benign prostate enlargement (BPE) have emerged as an alternative to transurethral resection of the prostate (TURP) and open prostatectomy (OP). A Medline search over the past 4 years was performed to assess the safety, intra- and postoperative morbidity of various laser techniques. Data on holmium laser enucleation of the prostate (HoLEP) show the highest grade of evidence with two meta-analyses available and prove the low intra- and postoperative morbidity with reproducible long-term results. Photoselective vaporization of the prostate (PVP) with the Greenlightlaser (potassium titanyl phosphate, KTP or lithium borate, LBO) is characterized by excellent haemostatic properties in patients with or without oral anticoagulation. Long-term results show a reoperation rate comparable with TURP; however, there is a lack of randomized trials. Various types of diode lasers with different wavelengths are available for laser vaporization; despite their favourable haemostatic properties, a higher invasion depth seems to result in necrosis of the tissue leading to a higher rate of reoperation. Thulium-laser resection of the prostate shows promising intra- and postoperative morbidity, but data are limited and initial results need to be confirmed in large-scale trials. In summary, HoLEP- and KTP-, or LBO-laser vaporization of the prostate are the most mature techniques of laser prostatectomy and treatment alternatives to TURP and OP, whereas the clinical value and durability of procedures with diode laser systems and the thulium laser need to be confirmed in high-quality prospective RCTs.

抗凝固薬継続下に施行したＨｏＬＥＰ（Ｈｏｌｍｉｕｍ Ｌａｓｅｒ Ｅｎｕｃｌｅａｔｉｏｎ ｏｆ ｔｈｅ Ｐｒｏｓｔａｔｅ）の経験

Oral anticoagulation (OA) has been considered as a strict contraindication to transurethral resection of the prostate (TURP). In recent years, some studies have shown that holmium laser enucleation of the prostate (HoLEP) has less blood loss compared to TURP. Thus we have performed HoLEP in patients with benign prostatic hyperplasia (BPH) under continuous OA from September 2009, and herein we report our first nine cases. Patients received HoLEP by a single surgeon at our institution. HoLEP was performed successfully in all patients. The mean times to complete enucleation and morcellation were 48.2 and 5.1 minutes, respectively. The mean tissue weight of enucleation was 37 grams. The mean hemoglobin and sodium loss after HoLEP were 1.7 g/dl and 1.3 mEq/L, respectively, and the catheterization time was 1.6 days. Blood transfusion, clot retention or transurethral resection syndrome were not observed in any cases. HoLEP has excellent hemostatic properties, and is a safe and effective procedure for patients with symptomatic BPH under the condition of continuous OA.

Safety of Holmium Laser Enucleation of the Prostate in Anticoagulated Patients

Oral anticoagulation (OA) is considered a strict contraindication to transurethral resection of the prostate (TURP). In recent years, however, safe and effective surgical alternatives such as holmium laser enucleation of the prostate (HoLEP) have emerged. Evidence from randomized trials has revealed that HoLEP has fewer bleeding complications than TURP, suggesting that HoLEP in anticoagulated patients is safer than TURP. However, published data evaluating bleeding complications in anticoagulated patients undergoing HoLEP are incomplete. Using a retrospective design, this is the first study to compare the bleeding complication rates of anticoagulated patients undergoing HoLEP to patients not on OA. We reviewed the electronic medical records of the first 76 HoLEP patients treated by a single urologist in two New England hospitals from May 2002 to September 2007. Thirty-nine were on OA, and 37 were controls. Thirteen patients were on coumadin (mean international normalized ratio [INR] 1.5), and 25 were on aspirin at the time of their surgery. Among the patients on OA, 8% (n = 2) had intraoperative hematuria compared to 14% (n = 5) of controls (p = 0.25). No patients in either group required blood transfusions. Stratifying the OA population revealed no statistical differences in bleeding complication rates between the coumadin, aspirin, and control groups (p = 0.34). Additionally, there were no differences in standard postoperative outcomes. These findings suggest that HoLEP has excellent hemostatic properties in high-risk patients and is a safe surgical alternative to TURP in patients on OA.

High Power Diode Laser Vaporization of the Prostate: Preliminary Results for Benign Prostatic Hyperplasia

Vaporization techniques using lasers have gained wide acceptance for benign prostatic hyperplasia as an alternative to transurethral prostate resection. The high power, 980 nm wavelength diode laser is a new promising alternative with a more rapid ablation rate and excellent hemostatic properties, as shown in ex vivo and in vivo animal models. We prospectively evaluated vaporization efficiency of the high power, 980 nm diode laser for bladder outlet obstruction due to benign prostatic hyperplasia. A total of 47 consecutive patients were included in the study. Inclusion criteria were maximal flow rate 12 ml per second or less with voided volume 150 ml or greater, International Prostate Symptom Score 12 or greater and quality of life score 3 or greater. Patients with a history of neurogenic voiding dysfunction, chronic prostatitis, or prostate or bladder cancer were excluded from analysis. Preoperative maximal flow rate, post-void residual urine, International Prostate Symptom Score, quality of life, International Index of Erectile Function-5, prostate specific antigen and prostate volume were compared with values at 3 and 6 months. Complications were assessed. Month 3 assessment revealed that the mean +/- SD International Prostate Symptom Score decreased significantly from 21.93 +/- 4.88 to 10.31 +/- 3.79 (p = 0.0001). The mean maximal flow rate increased significantly from 8.87 +/- 2.18 to 17.51 +/- 4.09 ml per second (p = 0.0001). Quality of life score changed considerably compared to baseline. All of these values showed slight improvement at month 6. There was no deterioration in erectile function according to the International Index of Erectile Function-5 short form. Post-void residual urine decreased significantly. Prostate volume and prostate specific antigen reductions were also significant. The most common postoperative complications were retrograde ejaculation (13 of 41 patients or 31.7%) and irritative symptoms (11 of 47 or 23.4%), which subsided in the maximal flow rate at 2 weeks. Recatheterization was necessary in 2 patients due to urinary retention after catheter removal. Two patients had temporary combined urge and stress incontinence for 2 weeks. Late bleeding in 1 patient 4 weeks postoperatively necessitated catheterization and irrigation. The high power diode laser provided significant improvements in International Prostate Symptom Score and the maximal flow rate with low morbidity. Thus, these results of prostate vaporization with the high power diode laser, representing what is to our knowledge the first clinical study in the literature, are encouraging.