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Thermal Injury (thermal + injury)
Selected AbstractsFeasibility and Safety of Using an Esophageal Protective System to Eliminate Esophageal Thermal Injury: Implications on Atrial-Esophageal Fistula Following AF AblationJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 11 2009MAURICIO S. ARRUDA M.D. Background: Ablation for atrial fibrillation (AF) requires energy delivery in close proximity to the esophagus (Eso) which has accounted for the LA-Eso fistula, a rare but life-threatening complication. Purpose: We evaluated an Eso cooling system to protect the Eso during RF ablation. Methods and Results: An "in vitro" heart-Eso preparation was initially used to test a temperature-controlled fluid-circulating system (EPSac [esophageal protective system],RossHart Technologies Inc.) and an expandable compliant Eso sac during cardiac RF delivery (4 mm tip, perpendicular to the heart, 15 g pressure) at 25, 35, and 45 W, 100 ± 5 , for 30 seconds with the EPSac at 25, 15, 10, and 5°C. All cardiac lesions were transmural. Eso thermal injury could only be avoided with the EPSac at 10 and 5°C. The system was then tested in 6 closed chest dogs, each receiving 12 RFs (LA aiming at the Eso) for 30 seconds: without EPSac (control) at 35 W (1 dog); at 45 W with EPSac at 25°C (1 dog), 10°C (2 dogs), and 5°C (2 dogs). The EPSac volume was intentionally increased to displace the Eso toward the LA (2 dogs 5 and 10°C). Eso injured control and EPSac at 25°C; Eso spared EPSac at 5 and 10°C, without Eso displacement. Shallow external Eso injury noted when intentionally displacing the Eso toward the LA. Conclusions: The EPSac spares the Eso from collateral thermal injury. It requires circulating fluid at 5 or 10°C and a compliant sac to avoid displacement of the Eso. Its safety and efficacy remain to be demonstrated in patients undergoing AF ablation. [source] Detection of Sublethal Thermal Injury in Salmonella enterica Serotype Typhimurium and Listeria monocytogenes Using Fourier Transform Infrared (FT-IR) Spectroscopy (4000 to 600 cm,1)JOURNAL OF FOOD SCIENCE, Issue 2 2008H.M. Al-Qadiri ABSTRACT:, Fourier transform infrared (FT-IR) spectroscopy (4000 to 600 cm,1) was utilized to detect sublethally heat-injured microorganisms: Salmonella enterica serotype Typhimurium ATCC 14028, a Gram-negative bacterium, and Listeria monocytogenes ATCC 19113, a Gram-positive bacterium. A range of heat treatments (N= 2) at 60 °C were evaluated: 0D (control), 2D, 4D, 6D, and 8D using a D60 °C (S. enterica serotype Typhimurium ATCC 14028 = 0.30 min, L. monocytogenes ATCC 19113 = 0.43 min). The mechanism of cell injury appeared to be different for Gram-negative and Gram-positive microbes as observed from differences in the 2nd derivative transformations and loadings plot of bacterial spectra following heat treatment. The loadings for PC1 and PC2 confirmed that the amide I and amide II bands were the major contribution to spectral variation, with relatively small contributions from C-H deformations, the antisymmetric P==O stretching modes of the phosphodiester nucleic acid backbone, and the C-O-C stretching modes of polysaccharides. Using soft independent modeling of class analogy (SIMCA), the extent of injury could be predicted correctly at least 83% of the time. Partial least squares (PLS) calibration analysis was constructed using 5 latent variables for predicting the bacterial counts for survivors of the different heat treatments and yielded a high correlation coefficient (R= 0.97 [S. enterica serotype Typhimurium] and 0.98 [L. monocytogenes]) and a standard error of prediction (SEP= 0.51 [S. enterica serotype Typhimurium] and 0.39 log10 CFU/mL [L. monocytogenes]), indicating that the degree of heat injury could be predicted. [source] Mobilization of endothelial progenitor cells into the circulation in burned patients,BRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 2 2008A. Fox Background: Bone marrow-derived endothelial progenitor cells (EPCs) have been detected in the peripheral blood of patients following thermal injury. EPCs migrate to sites of active neovascularization in response to mediators released after trauma, contributing to wound healing. The aim was to characterize levels and kinetics of EPCs in burned patients, then relate these to key mobilizing factors, vascular endothelial growth factor (VEGF) and the chemokine (C-X-C motif) ligand 12 (CXCL 12), and compare them with those in healthy subjects. Methods: The study included 19 adult patients with superficial or full-thickness burns and 50 blood donor volunteer controls. EPCs, identified by cell surface markers CD45dim/,, CD133+, CD144+ and VEGF receptor 2, were quantified by four-colour flow cytometry. Plasma VEGF and CXCL12 were measured using enzyme-linked immunosorbent assay. Results: Burned patients showed a rapid rise in EPC levels within 24 h, a ninefold increase compared with controls, returning to basal levels by 72 h. Body surface area burned correlated strongly with the degree of mobilization. EPC levels correlated significantly with rises in plasma VEGF and CXCL12. Conclusion: Thermal injury induced a rapid rise in EPCs that was proportional to the extent of the burn and significantly correlated with levels of angiogenic cytokines. Such cytokines may be used to stimulate EPCs as a future therapeutic target in burned patients. Copyright © 2007 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd. [source] Tissue-engineered tear secretory system: Functional lacrimal gland acinar cells cultured on matrix protein-coated substrataJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 1 2007Shivaram Selvam Abstract Dry eye is a general term that refers to a myriad of ophthalmic disorders resulting in the inadequate wetting of the corneal surface by the tear film. Dry eyes are typically treated by the application of artificial tears. However, patients with lacrimal insufficiencies such as Stevens-Johnson syndrome, chemical and thermal injuries, or ocular cicatricial pemphigoid have very limited options because of the short duration and action of lubricating agents. As a therapeutic strategy, we are working to develop a bioengineered tear secretory system for such patients. This article describes the growth and physiological properties of purified rabbit lacrimal gland acinar cells (pLGACs) on several matrix protein-coated polymers such as silicone, collagen I, copolymers of poly- D,L -lactide- co -glycolide (PLGA; 85:15 and 50:50), poly- L -lactic acid (PLLA), and Thermanox® plastic cell culture coverslips. Monolayers of acinar cells were established on all of the polymeric substrata. An assay of ,-hexosaminidase activity in the supernatant medium showed significant increases in protein secretion, following stimulation with 100 ,M carbachol on matrix protein-coated and uncoated polymers such as silicone, PLGA 85:15, and PLLA. Our study demonstrates that PLLA supported the morphological and physiological properties of purified rabbit lacrimal gland epithelial cells more successfully than the others. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2007 [source] Wet forced-air warming blankets are ineffective at maintaining normothermiaPEDIATRIC ANESTHESIA, Issue 7 2008ERICA P. LIN MD Summary Background:, Forced-air warming systems have proven effective in preventing perioperative hypothermia. To date, reported adverse events relate primarily to overheating and thermal injuries. This study uses a simple model to show that forced-air warming blankets become ineffective if they get wet. Methods:, Temperature sensor probes were inserted into three 1-liter fluid bags. Group C bags served as the control. Groups D (dry) and W (wet) bags were placed on Bair Hugger® Model 555 (Arizant Healthcare, Inc., Eden Prairie, MN, USA) pediatric underbody blankets. The warming blanket for Group W bags was subsequently wet with irrigation fluid. Temperature was documented every 5 min. This model was repeated two times for a total of three cycles. Statistical analysis was performed using anova for repeated measures. Results:, Starting temperatures for each model were within a 0.3°C range. Group C demonstrated a steady decline in temperature. Group D maintained and slightly increased in temperature during the observation period, while Group W exhibited a decrease in temperature at a rate similar to Group C. These results were significant at P < 0.005. Conclusions:, A wet forced-air warming blanket is ineffective at maintaining normothermia. Once wet, the warming blanket resulted in cooling similar to the control group. [source] Social health outcomes following thermal injuries: a retrospective matched cohort studyCHILD: CARE, HEALTH AND DEVELOPMENT, Issue 3 2010Richard Reading No abstract is available for this article. [source] Paradoxical Hypertrichosis After Laser Therapy: A ReviewDERMATOLOGIC SURGERY, Issue 3 2010SHRADDHA DESAI MD BACKGROUND Laser hair removal is a safe and effective procedure for the treatment of unwanted body hair but is not exempt from side effects. A rare but significant adverse effect with this treatment modality is paradoxical hypertrichosis. OBJECTIVE To evaluate the potential etiologies, risk factors, related laser types, and treatment options for the development of excess hair after laser therapy. MATERIALS AND METHODS An analysis of previously published case studies and review articles along with our own experience was used to gather information regarding this phenomenon. RESULTS Paradoxical hypertrichosis has a low incidence, ranging from 0.6% to 10%, and most commonly occurs on the face and neck. All laser and light sources have the potential to cause hair induction, especially in individuals with darker skin types (III,VI); with dark, thick hair; and with underlying hormonal conditions. Possible causes include the effect of inflammatory mediators and subtherapeutic thermal injury causing induction of the hair cycle. Treatment for paradoxical hypertrichosis is laser therapy of the affected area. CONCLUSIONS Paradoxical hypertrichosis is a rare side effect of laser hair removal; the pathogenesis of this event remains widely unknown. We recommend further large-scale studies to investigate this effect. The authors have indicated no significant interest with commercial supporters. [source] Laser-Assisted Hair Transplantation: Histologic Comparison Between CO2 and Ho:YAG LasersDERMATOLOGIC SURGERY, Issue 4 2001Eugene A. Chu MD Background. Various laser wavelengths and devices have been advocated for use in the creation of recipient channels during hair transplant surgery, including flash-scanned CO2, Ho:YAG (, = 2.12 ,m), and Er:YAG (, = 2.94 ,m). Objective. To determine the tissue injury caused by flash-scanned CO2 and pulsed Ho:YAG lasers during the creation of hair transplant recipient channels and to assess the efficacy of the Ho:YAG laser. Methods. Recipient channels were created in vivo in human scalp tissue using both lasers, and were excised and prepared for histologic examination. Optical micrometry of tissue sections was used to assess thermal injury. Results. The Ho:YAG laser created jagged, irregular-shaped channels with larger zones of thermal injury (superficial deepithelialization, thermal necrosis, and thermal damage). In contrast, the CO2 laser produced well-defined cylindrically shaped channels free of cellular debris with minimal epithelial disruption and significantly less lateral thermal injury. Conclusion. Given that the Ho:YAG produced larger regions of thermal injury and recipient channels that were unacceptable for graft, the CO2 laser remains the better choice for the creation of recipient channels during hair transplant surgery. However, ongoing research will be necessary to determine the optimal laser wavelength and/or devices for this procedure. [source] Temperature perception and nociceptionDEVELOPMENTAL NEUROBIOLOGY, Issue 1 2004Barry G. Green Abstract The specificity theory of somesthesis holds that perceptions of warmth, cold, and pain are served by separate senses. Although no longer accepted in all its details, the theory's basic assumptions of anatomical and functional specificity have remained guiding principles in research on temperature perception and its relationship to pain. This article reviews the response characteristics of thermoreceptors, temperature-sensitive nociceptors, and their associated pathways in the context of old and new perceptual phenomena, most of which cannot be satisfactorily explained by the specificity theory. The evidence indicates that throughout most of the perceptual range, temperature sensitivity depends upon coactivation of, and interactions among, thermal and nociceptive pathways that are composed of both specific "labeled lines" and nonspecific, multimodal fibers. Adding to this complexity is evidence that tactile stimulation can influence the way in which thermal stimulation is perceived. It is argued that thermoreception is best defined as a functional subsystem of somesthesis that serves the very different and sometimes conflicting demands of thermoregulation, protection from thermal injury, and haptic perception. © 2004 Wiley Periodicals, Inc. J Neurobiol 61: 13,29, 2004 [source] Endo-robotic resection of the submandibular gland in a cadaver model,HEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 11 2005David J. Terris MD Abstract Background. By means of a prospective, nonrandomized investigation, we evaluated the feasibility of performing endo-robotic resection of the submandibular gland in a cadaver model and compared the results of robotically enhanced endoscopic surgery with those from a conventional endoscopic technique. Methods. Procedural times were recorded in a consecutive series of 11 endoscopic submandibular gland resections using the daVinci Surgical System (Intuitive Surgical, Sunnyvale, CA) and a modified endoscopic surgical approach previously developed in a porcine model. The presence of neurovascular injury was assessed postoperatively, and the specimens were examined histologically. Results. Eleven endo-robotic submandibular gland resections were successfully performed in six cadavers (no conversions to open resection were necessary). The median duration of the procedures was 48 minutes (range, 33,82 minutes). Creation of the operative pocket took an average (±SD) of 12.2 ± 5.3 minutes, assembly of the robot required 9.3 ± 4.1 minutes, and the mean time for submandibular gland resection was 29.4 ± 8.9 minutes. The time required for robotic assembly was offset by the reduced operative time necessary compared with conventional endoscopic resection. Histologic examination confirmed the presence of normal glandular architecture, without evidence of excessive mechanical or thermal injury. There were no cases of apparent neurovascular injury. Conclusions. Robotically enhanced endoscopic surgery in the neck is feasible and offers a number of compelling advantages over conventional endoscopic neck surgery. Clinical trials will be necessary to determine whether these advantages can be achieved in clinical practice. © 2005 Wiley Periodicals, Inc. Head Neck27: XXX,XXX, 2005 [source] Feasibility and Safety of Using an Esophageal Protective System to Eliminate Esophageal Thermal Injury: Implications on Atrial-Esophageal Fistula Following AF AblationJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 11 2009MAURICIO S. ARRUDA M.D. Background: Ablation for atrial fibrillation (AF) requires energy delivery in close proximity to the esophagus (Eso) which has accounted for the LA-Eso fistula, a rare but life-threatening complication. Purpose: We evaluated an Eso cooling system to protect the Eso during RF ablation. Methods and Results: An "in vitro" heart-Eso preparation was initially used to test a temperature-controlled fluid-circulating system (EPSac [esophageal protective system],RossHart Technologies Inc.) and an expandable compliant Eso sac during cardiac RF delivery (4 mm tip, perpendicular to the heart, 15 g pressure) at 25, 35, and 45 W, 100 ± 5 , for 30 seconds with the EPSac at 25, 15, 10, and 5°C. All cardiac lesions were transmural. Eso thermal injury could only be avoided with the EPSac at 10 and 5°C. The system was then tested in 6 closed chest dogs, each receiving 12 RFs (LA aiming at the Eso) for 30 seconds: without EPSac (control) at 35 W (1 dog); at 45 W with EPSac at 25°C (1 dog), 10°C (2 dogs), and 5°C (2 dogs). The EPSac volume was intentionally increased to displace the Eso toward the LA (2 dogs 5 and 10°C). Eso injured control and EPSac at 25°C; Eso spared EPSac at 5 and 10°C, without Eso displacement. Shallow external Eso injury noted when intentionally displacing the Eso toward the LA. Conclusions: The EPSac spares the Eso from collateral thermal injury. It requires circulating fluid at 5 or 10°C and a compliant sac to avoid displacement of the Eso. Its safety and efficacy remain to be demonstrated in patients undergoing AF ablation. [source] Pain and Anatomical Locations of Radiofrequency Ablation as Predictors of Esophageal Temperature Rise During Pulmonary Vein IsolationJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 1 2008ARASH ARYANA M.D. Introduction: Esophageal temperature rise (ETR) during ablation inside left atrium has been reported as a marker for esophageal thermal injury. We sought to investigate the possible relationships between chest pain and ETR during radiofrequency (RF) ablation, and ETR and locations of RF application, in patients undergoing pulmonary vein (PV) isolation under moderate sedation. Methods and Results: We analyzed anatomical locations of each RF application and its association with esophageal temperature and presence/absence of pain. Data from 40 consecutive patients (mean age: 56 ± 10 years) were analyzed. There were a total of 4,071 RF applications resulting in 291 episodes of pain (7.1%) and 223 ETRs (5.5%). Thirty-five patients (87.5%) experienced at least one pain episode and 32 (80.0%) had at least one ETR. While 77.4% of posterior wall applications that caused pain also corresponded to an ETR (P < 0.0001), only 0.8% of pain-free posterior wall applications were associated with ETRs (P < 0.0001). The sensitivity and specificity of pain during ablation for ETR were 94% and 98%, respectively. No ETRs were observed during anterior wall applications. ETRs occurred more frequently during ablation on the left (86.1%) versus the right (13.9%), and in inferior (70.4%) versus superior (29.6%) segments. Conclusion: In patients undergoing PV isolation, ETR was encountered when ablating in the posterior left atrium with the distribution left > right and inferior > superior. Pain during ablation was associated with ETR, and lack of pain was strongly associated with absence of ETR. Pain during RF ablation may thus serve as a predictor of esophageal heating and potential injury. [source] Esophageal Temperature During Radiofrequency-Catheter Ablation of Left Atrium: A Three-Dimensional Computer Modeling StudyJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 4 2006FERNANDO HORNERO M.D., Ph.D. Introduction: There is current interest in finding a way to minimize thermal injury in the esophagus during radiofrequency-catheter ablation of the left atrium. Despite the fact that the esophageal temperature is now being monitored during ablation, the influence of different anatomic and technical factors on the temperature rise remains unknown. Methods and Results: We implemented a three-dimensional computational model that included atrial tissue, epicardial fat, esophagus, aorta, and lung, all linked by connective tissue. The finite-element method was used to calculate the esophageal temperature distribution during a procedure of constant-temperature ablation with an 8-mm electrode, under different tissue conditions. Results showed that the distance between electrode and esophagus was the most important anatomic factor in predicting the esophageal temperature rise, the composition of the different tissues being of lesser importance. The measurement of the esophageal temperature in different sites of the lumen offered differences up to 3.7°C, especially for a short electrode,esophagus distance (5 mm). The difference in the convective cooling by circulating blood around electrode and endocardium did not show a significant influence on the esophageal temperature rise. Conclusion: Computer results suggest that (1) the electrode,esophagus distance is the most important anatomic factor; (2) the incorrect positioning of an esophageal temperature probe could give a low reading for the maximum temperature reached in the esophagus; and (3) the different cooling effect of the circulating blood flow at different atrial sites has little impact on the esophageal temperature rise. [source] Real-Time Monitoring of Luminal Esophageal Temperature During Left Atrial Radiofrequency Catheter Ablation for Atrial Fibrillation: Observations About Esophageal Heating During Ablation at the Pulmonary Vein Ostia and Posterior Left AtriumJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 2 2006CHRISTIAN PERZANOWSKI M.D. Introduction: Left atrial radiofrequency catheter ablation (RFA) is gaining acceptance as treatment for drug-refractory atrial fibrillation (AF). This therapy has been associated with esophageal injury and atrioesophageal fistula formation causing death. Methods: We describe 3 patients undergoing catheter ablation for AF during real-time monitoring of luminal esophageal temperature. Results: We observed heating of the esophagus during short duration low power RFA, at either the left or right pulmonary vein ostia. Cryoablation at the pulmonary vein ostium in one patient resulted in esophageal cooling. Furthermore, we observed that fluoroscopic localization of the ablation catheter at a site apparently distant from the esophagus is not adequate to assure avoidance of ablation-induced esophageal heating. Conclusions: Real-time monitoring of luminal esophageal position and temperature is feasible, enhances recognition of esophageal heating, and may add useful information beyond that provided by fluoroscopic assessment of esophageal position. There is a potential role for esophageal monitoring to help avoid thermal injury to the esophagus during catheter ablation for atrial fibrillation. [source] Intraductal chilled saline perfusion to prevent bile duct injury during percutaneous radiofrequency ablation for hepatocellular carcinomaJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 8pt2 2008Takaya Ohnishi Abstract Background and Aim:, Radiofrequency ablation (RFA) is a promising, minimally invasive treatment for hepatocellular carcinoma (HCC). However, thermal injury sometimes occurs in the bile duct, potentially leading to a critical situation. The aim of the present study was to investigate whether bile duct injury is reduced by an intraductal chilled saline perfusion (ICSP) through a nasobiliary tube during RFA for HCC. Patients and Methods:, The baseline incidence of bile duct injury at Gifu Municipal Hospital was 3.1% (13 patients) in 424 patients with HCC treated by percutaneous RFA. In all patients, the tumor was within 5 mm of the central bile duct on CT images. The incidence of bile duct injury was 46% among the 28 selected patients whose tumor was close to the central bile duct. To prevent complications in such high-risk patients, we placed a nasobiliary tube endoscopically before RFA, and performed ICSP during RFA. Forty consecutive patients with tumors close to the central bile duct were enrolled in this study. Results:, Of the 40 enrolled patients, only one had biliary injury, whereas the remaining 39 patients were able to avoid it. The incidence of biliary injury was significantly reduced in the ICSP group (1/40, 2.5%) compared to that in the control group (13/28, 46%) (P < 0.0001). Moreover, the liver function 6 months after RFA was also better preserved in the ICSP group according to Child,Pugh grading, thus resulting in a better clinical outcome. Conclusions:, ICSP through a nasobiliary tube is a potential intervention method to prevent biliary injury by percutaneous RFA. [source] Early versus late enteral nutritional support in adults with burn injury: a systematic reviewJOURNAL OF HUMAN NUTRITION & DIETETICS, Issue 2 2007J. Wasiak Abstract Background Burn injury increases the body's metabolic demands, and therefore nutritional requirements. Provision of an adequate supply of nutrients is believed to lower the incidence of metabolic abnormalities, thus reducing septic morbidity, and improving survival rates. Enteral nutrition support is the best feeding method in a patient who is unable to achieve an adequate oral intake, but optimal timing of its introduction after burn injury (i.e. early versus late) needs to be established. The purpose of this review is to examine evidence for the effectiveness and safety of early versus late enteral nutrition support in adults with burn injury. Methods An examination of randomized and controlled clinical trials using various medical databases such as The Cochrane Library (Issue 3, 2006), MEDLINE (from 1950), CINHAL (from 1982) and EMBASE (from 1980). Results The trial evidence about the benefit of early enteral nutritional support on standardized clinical outcomes such as length of hospital stay and mortality remained inconclusive. Similarly, the question of whether early enteral feeding influenced or decreased metabolic rate, reduced septic and other complications remained uncertain. Conclusions Promising results suggest early enteral nutrition support may blunt the hypermetabolic response to thermal injury, but it is insufficient to provide clear guidelines for practice. Further research incorporating larger sample sizes and rigorous methodology that utilizes valid and reliable outcome measures is essential. [source] Precooling of the femoral canal enhances shear strength at the cement,prosthesis interface and reduces the polymerization temperatureJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 9 2006Pang-Hsin Hsieh Abstract Preheating of the femoral stem in total hip arthroplasty improves the cement,prosthesis bond by decreasing the interfacial porosity. The main concern, however, is the potential thermal osteonecrosis because of an increased polymerization temperature. In this study, the effects of femoral canal precooling on the characteristics of the cement,stem interface were evaluated in an experimental model for three test conditions: precooling of the femoral canal, preheating of the stem (44°C), and a control in which stems were inserted at room temperature without thermal manipulation of the implant, cement, or bone. Compared to the control group, precooling of the femoral canal and preheating of the stem had similar effects on the cement,stem interface, with greater interfacial shear strength and a reduced porosity. Femoral canal precooling also produced a lower temperature at the cement,bone interface. No difference was found in the ultimate compressive strength of bone cement for the three preparation conditions. Based on this laboratory model, precooling of the femoral canal could improve shear strength and porosity at the stem,cement interface, minimize thermal injury, and maintain the mechanical strength of the cement. © 2006 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res [source] MR-guided ablation of hepatocellular carcinoma aided by gadoxetic acidJOURNAL OF SURGICAL ONCOLOGY, Issue 8 2007FACS, FRCSC, Oliver F. Bathe MD Abstract Local recurrences are problematic following radiofrequency ablation (RFA) of hepatocellular carcinoma. Intraoperative magnetic resonance imaging (iMRI) is a potentially useful tool for the assessment of the extent of the thermal injury produced by RFA. The use of gadoxetic acid disodium, a hepatocyte-specific contrast agent with prolonged retention, is described as a method of improved assessment of the ablative margins relative to the tumor margins. J. Surg. Oncol. 2007;95:670,673. © 2007 Wiley-Liss, Inc. [source] The effects of multiple passes on the epidermal thermal damage pattern in nonablative fractional resurfacing,LASERS IN SURGERY AND MEDICINE, Issue 2 2009Dieter Manstein MD Background and Objective Nonablative fractional resurfacing is a concept of cutaneous re-modeling whereby laser-induced microscopic treatment zones (MTZs) are surrounded by normal viable tissue. Such thermal damage pattern with a small diameter of individual lesions allows fast re-epithelialization with minimal side effects. The purpose of this in vitro study was to determine the fraction of thermal injury per unit surface area (fill factor) and lesion size in relation to pulse energy and number of passes. Methods Full thickness abdominal skin samples were exposed ex vivo to the Fraxel SR 750 laser (Reliant Technologies, Mountain View, CA). One set of exposures was performed for pulse energies in the range of 8 to 40 mJ for a single pass at 250 MTZ/cm2. A second set of exposures was performed at 10 mJ with number of passes from 1 to 30. The thermal damage pattern was assessed by incubation of epidermal sheets with NitroBlueTetrazoliumChloride (NBTC) stain. Size of individual MTZ and fill factor were determined by image analysis (ImageJ, NIH, Bethesda, MD) of digital micrographs. Results Width of the thermal injury zone was directly related to the pulse energy used. The fill factor did not have a uniform relationship with the number of passes. Due to the stochastic placement of individual MTZs, even for greater number of passes, some residual undamaged tissue was found. Due to formation of thermal damage clusters, defined as overlapping individual MTZs, the size of the resulting clustering lesions which we defined as microscopic treatment cluster (MTC) increased linearly as a function of the number of passes. Conclusion We have described the fill factor as it relates to the number of passes and have demonstrated that the average size of individual lesions depends on the number of passes. Clustering of MTZs lead to the development of MTC, the average size of which increased with the number of passes. The clinical implications of these findings are contingent on further studies. Lasers Surg. Med. 41:149,153, 2009. © 2009 Wiley-Liss, Inc. [source] Ex vivo histological characterization of a novel ablative fractional resurfacing device,LASERS IN SURGERY AND MEDICINE, Issue 2 2007Basil M. Hantash MD Abstract Background and Objectives We introduce a novel CO2 laser device that utilizes ablative fractional resurfacing for deep dermal tissue removal and characterize the resultant thermal effects in skin. Study Design/Materials and Methods A prototype 30 W, 10.6 µm CO2 laser was focused to a 1/e2 spot size of 120 µm and pulse duration up to 0.7 milliseconds to achieve a microarray pattern in ex vivo human skin. Lesion depth and width were assessed histologically using either hematoxylin & eosin (H&E) or lactate dehyrdogenase (LDH) stain. Pulse energies were varied to determine their effect on lesion dimensions. Results Microarrays of ablative and thermal injury were created in fresh ex vivo human skin irradiated with the prototype CO2 laser device. Zones of tissue ablation were surrounded by areas of tissue coagulation spanning the epidermis and part of the dermis. A thin condensed lining on the interior wall of the lesion cavity was observed consistent with eschar formation. At 23.3 mJ, the lesion width was approximately 350 µm and depth 1 mm. In this configuration, the cavities were spaced approximately 500 µm apart and interlesional epidermis and dermis demonstrated viable tissue by LDH staining. Conclusion A novel prototype ablative CO2 laser device operating in a fractional mode was developed and its resultant thermal effects in human abdominal tissue were characterized. We discovered that controlled microarray patterns could be deposited in skin with variable depths of dermal tissue ablation depending on the treatment pulse energy. This is the first report to characterize the successful use of ablative fractional resurfacing as a potential approach to dermatological treatment. Lasers Surg. Med. 39:87,95, 2007. © 2007 Wiley-Liss, Inc. [source] The effects of ketamine and propofol on bacterial translocation in rats after burn injuryACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 2 2005H. Yagmurder Background:, Bacterial translocation (BT) occurs after thermal injury and may result from an ischemic intestinal insult. The aim of the study was to investigate the effects of ketamine and propofol as anesthetic agents on BT in an animal model of burn injury. Methods:, Sixty male Wistar Albino rats were randomly assigned to six groups of 10 rats each. Anesthesia was induced and maintained with ketamine in groups 1, 2 and 3 and with propofol in groups 4, 5 and 6 during 6 h. Groups 2, 3, 5 and 6 received 30% total body surface area (TBSA) third-degree burns. Groups 1 and 4 had no burn injury. Then, they were allowed to recover from the anesthesia at the end of 6 h. Mean arterial pressure (MAP) was monitored continuously and maintained within 10% of baseline (before burn injury) levels in all animals. Animals in groups 3 and 6 had a laparotomy to obtain a tissue sample from the terminal ileum for determination of intestinal lipid peroxidation by-product malondialdehyde (MDA) before (baseline) and 6 and 24 h after burn injury (ABI). So these animals were not included in the BT studies. At postburn 24 h, animals in groups 1, 2 and 4, 5 were sacrified and samples were taken from the mesenteric lymph nodes (MLN), liver and spleen for bacteriologic cultures. Results:, The incidence of BT was found to be significantly higher in group 2 than in all the other groups. Bacterial translocation incidence of group 5 was not significantly different from that of groups 4 and 1. Group 5 was associated with a significantly reduced number of enteric organisms per gram of tissue compared to group 2. Baseline MDA contents of groups 3 and 6 were similar. Ileal MDA levels were increased in group 3, but there were no significant changes in group 6 at 6 and 24 h ABI compared to baseline. Conclusion:, Our results suggest that propofol as an anesthetic agent may prevent BT by scavenging reactive oxygen species and inhibiting lipid peroxidation in an animal model of burn injury. [source] In reference to Histologic assessment of thermal injury to tonsillectomy specimens: a comparison of electrocautery, coblation, harmonic scalpel, and tonsillotomeTHE LARYNGOSCOPE, Issue 5 2010Douglas Hetzler MD No abstract is available for this article. [source] IMPACT OF BLOOD FLOW OCCLUSION ON LIVER NECROSIS FOLLOWING THERMAL ABLATIONANZ JOURNAL OF SURGERY, Issue 1-2 2006Mehrdad Nikfarjam Background: Laser, radiofrequency and microwave are common techniques for local destruction of liver tumours by thermal ablation. The main limitation of thermal ablation treatment is the volume of necrosis that can be achieved. Blood flow occlusion is commonly advocated as an adjunct to thermal ablation to increase the volume of tissue necrosis based on macroscopic and histological assessment of immediate or direct thermal injury. This study examines the impact of blood flow occlusion on direct and indirect laser induced thermal liver injury in a murine model using histochemical methods to assess tissue vitality. Methods: Thermal ablation produced by neodymium yttrium-aluminium-garnet laser (wavelength 1064 nm) was applied to the liver of inbred male CBA strain mice at 2 W for 50 s (100 J). Treatment was performed with and without temporary portal vein and hepatic artery blood flow occlusion. Animals were killed upon completion of the procedure to assess direct thermal injury or at 24, 48 and 72 h to assess the progression of tissue damage. The maximum diameter of necrosis was assessed by vital staining for nicotinamide adenine dinucleotide (NADH) diaphorase. Microvascular changes were assessed by laser Doppler flowmetry, confocal in vivo microscopy and scanning electron microscopy. Results: The direct thermal injury (mean SE) assessed by NADH diaphorase staining was significantly greater following thermal ablation treatment without blood flow occlusion than with blood flow occlusion (3.3 (0.4) mm vs 2.9 (0.3) mm; P = 0.005). Tissue disruption, cracking and vacuolization was more pronounced adjacent to the fibre insertion site in the group treated with thermal ablation combined with blood flow occlusion. There was an equivalent increase in the extent of injury following therapy in both groups that reached a peak at 48 h. The maximum diameter of necrosis in the thermal ablation alone group at 48 h was significantly greater than the thermal ablation combined with blood flow occlusion group (5.8 (0.4) mm vs 5.3 (0.3) mm; P = 0.011). The patterns of microvascular injury were similar in both groups, varying in extent. Conclusion: Temporary blood flow inflow occlusion appears to decrease the extent of initial injury measured by vital staining techniques and does not alter the time sequence of progressive tissue injury following thermal ablation therapy. [source] Temperature changes in dental pulp associated with use of power grinding equipment on equine teethAUSTRALIAN VETERINARY JOURNAL, Issue 1-2 2005GJ WILSON Objective To quantify the temperature changes in the dental pulp associated with equine dental procedures using power grinding equipment. Design A matrix experimental design with replication on the same sample was followed to allow the following independent variables to be assessed: horse age (young or old), tooth type (premolar or molar), powered grinding instrument (rotating disc or die grinder), grinding time (15 or 20 seconds) and the presence or absence of water coolant. Procedure Sound premolar and molar teeth from a 6-year-old horse and a 15-year-old horse, which had been removed postmortem, were sectioned parallel to the occlusal plane to allow placement of a miniature thermocouple at the level of the dental pulp. The maximum temperature increase, the time taken to reach this maximum and the cooling time were measured (n=10 in each study). The teeth were placed in a vice and the instrument used on the tooth as per clinical situation. Results Significant differences were recorded for horse age (P < 0.001), instrument type (P < 0.001), grinding time (P < 0.001) and presence or absence of coolant (P < 0.001). There was no significant difference for tooth type. Conclusion Thermal insult to the dental pulp from the use of power instruments poses a significant risk to the tooth. This risk can be reduced or eliminated by appropriate selection of treatment time and by the use of water irrigation as a coolant. The increased dentine thickness in older horses appears to mitigate against thermal injury from frictional heat. [source] Laparoscopic debulking of bulky lymph nodes in women with cervical cancer: indication and surgical outcomesBJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 5 2009R Tozzi Objective, To describe the technique and the surgical outcome of laparoscopic resection of bulky lymph nodes before adjuvant treatment. Design, Prospective pilot study. Setting, Gynaecological oncology cancer centre. Population, From January 2006 to February 2008, 22 consecutive women presented with cervical cancer and bulky metastatic lymph nodes (>2 cm). Methods, All women underwent resection of bulky lymph nodes by laparoscopy. A prospective record of the main surgical outcomes was performed. Main outcome measures, Safety and efficacy of laparoscopic resection of bulky lymph nodes, conversion to laparotomy, intra- and perioperative morbidity. Results, All the operations were completed by laparoscopy. Median operative time was 197 minutes (range 180,320). Median blood loss was 60 cc (range 10,100), two women experienced complications: one thermal injury of the sciatic root provoking postoperative leg palsy and one chylous ascites. The woman with the thermal injury has recovered most leg function with physiotherapy and the woman with chylous ascites recovered within 2 weeks, slightly delaying the adjuvant treatment. All women were discharged within 4 days from the operation (range 2,4). Pathology reports confirmed the presence of tumour metastases and the lymph nodes size. The adjuvant treatment started at a median time of 12 days (range 3,22). Conclusion, Debulking of large pelvic and para-aortic lymph nodes was effectively accomplished by laparoscopy in all 22 women with 9% complication rate. The surgical outcome is similar to historical series on women operated on by laparotomy, with the advantage of a faster recovery and an early start of adjuvant treatment. [source] Mobilization of endothelial progenitor cells into the circulation in burned patients,BRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 2 2008A. Fox Background: Bone marrow-derived endothelial progenitor cells (EPCs) have been detected in the peripheral blood of patients following thermal injury. EPCs migrate to sites of active neovascularization in response to mediators released after trauma, contributing to wound healing. The aim was to characterize levels and kinetics of EPCs in burned patients, then relate these to key mobilizing factors, vascular endothelial growth factor (VEGF) and the chemokine (C-X-C motif) ligand 12 (CXCL 12), and compare them with those in healthy subjects. Methods: The study included 19 adult patients with superficial or full-thickness burns and 50 blood donor volunteer controls. EPCs, identified by cell surface markers CD45dim/,, CD133+, CD144+ and VEGF receptor 2, were quantified by four-colour flow cytometry. Plasma VEGF and CXCL12 were measured using enzyme-linked immunosorbent assay. Results: Burned patients showed a rapid rise in EPC levels within 24 h, a ninefold increase compared with controls, returning to basal levels by 72 h. Body surface area burned correlated strongly with the degree of mobilization. EPC levels correlated significantly with rises in plasma VEGF and CXCL12. Conclusion: Thermal injury induced a rapid rise in EPCs that was proportional to the extent of the burn and significantly correlated with levels of angiogenic cytokines. Such cytokines may be used to stimulate EPCs as a future therapeutic target in burned patients. Copyright © 2007 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd. [source] The Presence of B-type Natriuretic Peptide in Burns and the Responsiveness of Fibroblasts to BNP: Proof of PrincipleACADEMIC EMERGENCY MEDICINE, Issue 6 2007Adam J. Singer MD Background:B-type natriuretic peptide (BNP) released from cardiac myocytes plays an important role in cardiac homeostasis through cyclic guanosine monophosphate (cGMP) activation. BNP also reduces cardiac remodeling and fibrosis. The antifibrotic effects of BNP are mediated in part by blocking the effects of transforming growth factor ,, a profibrotic cytokine that plays a significant role in cutaneous wound healing. It is unclear if BNP plays any role in cutaneous wound healing.ObjectivesTo investigate if BNP levels would be elevated in thermally injured human skin and if human-derived fibroblasts would respond to BNP exposure by increasing levels of cGMP.MethodsThis was an in vitro analysis of human skin. Skin samples and cells were collected from patients with and without thermal injury. The authors stained three skin samples from normal skin (taken at the time of elective cosmetic surgery) with antibodies to BNP and compared these with three tissue samples obtained from burned human skin taken during tangential excision of deep burns. Normal human-derived fibroblasts and keratinocytes were exposed in triplicate to BNP in vitro, and cGMP accumulation was evaluated. Levels of cGMP were quantified and compared with analysis of variance.ResultsBNP was present in all specimens of thermally injured skin (especially around collagen, epithelial cells, and endothelial cells) but not in any uninjured skin samples (p = 0.05, single-tailed Fisher's exact test). In vitro grown fibroblasts showed significant increases of cGMP levels with increasing levels of BNP exposure (mean [±SD]: 0.6 [±0.3], 1.2 [±0.2], 4.6 [±0.1], and 5.0 [±0.9] pmol/mL with BNP concentrations of 0, 10, 500, and 1,000 nmol/L, respectively; p < 0.001). The effect of BNP on keratinocytes was minimal and below the level of quantification.Conclusions:These findings demonstrate proof of principle that human fibroblasts are responsive to the effects of BNP in vitro and that BNP is present in injured skin, suggesting that BNP may play a role in cutaneous wound healing. [source] n-3 Fatty acid supplementation in burned paediatric patientsACTA PAEDIATRICA, Issue 12 2009MC Marín Abstract Aim:, To determine the effect of dietary supplementation with n-3 fatty acids (FA) in paediatric burned patients who had less than 20% of total body surface affected. Methods:, Burned patients were randomly assigned into two groups, one of them received a supplement of n-3 FA during 5 weeks; the other group was considered as not n-3 supplemented burned group. A third group of no burned patients was selected as control. Blood samples were collected at admission and in burned groups at the final of the study. Plasma and erythrocyte phospholipid FA composition and some biochemical parameters related to the clinical evolution: total plasma proteins and C3 and C4 complement proteins were determined. Results:, In the early post-burn patients, there is an increase in saturated and monounsaturated FAs in plasma phospholipids, and a decrease in polyunsaturated FAs compared with control. These alterations are in favour of proinflammatory response to burn injury. In n-3 FA supplemented group, these changes were further reverted, and a favourable response in the amount of total plasma proteins and in C3 and C4 proteins of the complement system was demonstrated. Conclusion:, Dietary n-3 FA supplementation might be beneficial for patients suffering thermal injury. [source] Randomized-controlled study comparing post-operative pain between coblation palatoplasty and laser palatoplasty,CLINICAL OTOLARYNGOLOGY, Issue 2 2006Belloso A. Objectives:, This study aimed to evaluate differences in post-operative pain comparing KTP laser-assisted uvulopalatoplasty without tonsillectomy (LAUP) with a new described surgical method: coblation uvulopalatoplasty with tonsillectomy (CP). We also evaluate the impact of each surgical technique in reduction of snoring loudness. Material and methods:, Single blind randomized-controlled trial. From a population of 41 consecutive patients on the waiting list for uvulopalatoplasty for simple snoring, the study group was reduced to 17 CP and 13 LAUP. Post-operative pain and reduction of snoring loudness were recorded using visual analogue scales (VAS) during the first 15 post-operative days. Post-operative snoring loudness was documented for 1-year period. Results:, Both groups had similar post-operative pain during the first seven post-operative days. A statistically significant reduction in post-operative pain was observed in the CP group after day 8, and maintained until the end of the study. Reduction of snoring loudness was significant in both groups, but no differences were observed between them. Discussion:, Coblation uvulopalatoplasty compared with LAUP demonstrates a reduction in post-operative pain, significant after the first post-operative week. The collateral thermal injury caused by laser is responsible for the slow-healing rate and maintained post-operative pain. Coblation dissociates tissue at lower temperatures with minimal collateral thermal injury and consequently faster and less painful recovery. Both surgical procedures have significant and similar reduction in snoring loudness. Conclusions:, Both methods are adequate treatment options for snoring. The less painful recovery in CP promotes this surgical technique as our preferred choice for palate surgery. [source] | ||||||||||||||||||||||||||||