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Jai Raman - One of the best experts on this subject based on the ideXlab platform.
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primary Sternal plating in high risk patients prevents mediastinitis
European Journal of Cardio-Thoracic Surgery, 2004Co-Authors: David H. Song, Valluvan Jeevanandam, Robert F Lohman, John Renucci, Jai RamanAbstract:OBJECTIVE: Sternal wound infection leading to post-operative mediastinitis is a devastating complication of cardiac surgery carrying nearly a 15% mortality rate despite current treatment methods. Instability of bone fragments pre-disposes a patient to have non-union, mal-union and can subsequently lead to deep Sternal wound infections progressing to mediastinitis. Rigid plate fixation has been utilized for acquired and surgically created fractures of virtually every bone in the body to prevent instability. However, the current standard for sternotomy closure remains the method of wire-circlage. Application of rigid plate fixation for Sternal osteotomies affords greater stability of the sternum. We report on our preliminary experience with this technique in high-risk patients. METHODS: From July of 2000 to December 2001, rigid plate fixation was applied to 45 patients designated as having high risk for Sternal dehiscence and subsequent mediastinitis. High risk was defined as patients having 3 or more established historical risk factors, including: COPD, Re-Operative Surgery, Renal Failure, Diabetes, Chronic Steroid Use, Morbid Obesity, Concurrent Infection and Acquired or Iatrogenic Immunosuppression. Intra-operative risk factors included off-midline sternotomy, osteoporosis, long cardio-pulmonary bypass runs (>2 h), transverse fractures of the sternum. Rigid plate fixation was performed using a combination of plates secured by bi-cortical screws, after the cardiac surgical procedure was complete and hemostasis was secured. RESULTS: Rigid plate fixation was performed on 26 males and 19 females. The average age of patients was 63 (43-88) years. The average follow-up was 15 weeks (range 8-41 weeks). While there were 4 peri-operative deaths unrelated to Sternal closure: one from aspiration pneumonia (post-operative day 9), one from a pulmonary embolus (post-operative day 29), one from overwhelming sepsis from pre-existing endocarditis (post-operative day 15), and one for primary respiratory failure (post-operative day 12). All others healed successfully. One patient who had a sterile dehiscence subsequently underwent successful re-operative rigid fixation. Comparing the cohort of patients who received rigid plate fixation to a matched population of high-risk patients during a similar time period who received wire closure, revealed a significant difference in the incidence of post-operative mediastinitis. The wire closed group (n = 207) had 18 deaths unrelated to Sternal closure and had 28 patients who developed mediastinitis (14.8%). The rigid plate fixation group had no mediastinitis (Fisher's exact test, P = 0.006). The total incidence of post-operative mediastinitis during the designated study period was 4.2%. CONCLUSION: Patients who benefited from Sternal closure with rigid plate fixation showed a significant decrease in the incidence of post-operative mediastinitis when compared to similar population of patients whose Sterna were closed with wire.
Pedro E Saucedo - One of the best experts on this subject based on the ideXlab platform.
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growth and reproduction patterns of the winged pearl oyster pteria Sterna cultivated in tropical environments of mexico implications for pearl farming
Ciencias Marinas, 2014Co-Authors: Irene Sernagallo, Javier M J Ruizvelazco, Hector Acostasalmon, Emilio Penamessina, Guadalupe Torreszepeda, Pedro E SaucedoAbstract:The winged pearl oyster, Pteria Sterna, sustains a growing pearl industry in northwestern Mexico, where a subtropical climate prevails. In tropical areas of Mexico, pearl cultivation may be profitable, but insufficient information on the biology and ecology of the species limits the definition of protocols for creating pearl farms. We measured absolute growth, growth rate, reproductive stages, changes in oocyte size, and size at first maturity of juvenile P. Sterna cultivated in Bahia de Acapulco over one annual cycle (2009–2010), and compared their response in this tropical area with reports from subtropical areas of Mexico. We also compared the von Bertalanffy growth model with one proposed in this study for aquaculture purposes. The growth rate was higher during the first six months (5.3 mm month–1) and then decreased to 3 mm month–1 until juveniles reached a size of 60 mm in one year. Growth rates were higher in February and lower in July through September. Both models described well the growth of P. Sterna, but the adjustment and the estimation of parameters was better with the proposed model. Gametogenesis started in December 2009 at 50.9 mm (males) and 59.5 mm (females); gonad development occurred continuously throughout the year with a peak in February–March (~25–26 oC; 2.8 µg L–1 chlorophyll a concentration), when the gonad index was highest and oocytes were larger. When compared to other studies conducted in subtropical areas, the species uses different strategies to channel available energy into growth and reproduction in tropical regions; P. Sterna grows quickly in Bahia de Acapulco and may obtain the size necessary for grafting (70–80 mm shell height) in 15–17 months. La concha nacar Pteria Sterna sostiene una creciente industria perlera en la region subtropical del noroeste de Mexico. En ambientes tropicales del pais, el cultivo de perlas puede ser redituable, pero la poca informacion sobre la biologia y ecologia de la especie limita la definicion de protocolos para la creacion de granjas perleras. Se determino el crecimiento absoluto, la tasa de crecimiento, los estadios reproductivos, los cambios en la talla de ovocitos y la talla de primera madurez de juveniles de P. Sterna cultivados en la bahia de Acapulco durante el ciclo anual 2009–2010, y se comparo su respuesta en esta area tropical con registros de la especie para otras areas subtropicales de Mexico. Se comparo el modelo de crecimiento de von Bertalanffy con uno propuesto en este estudio para fines acuaculturales. La tasa de crecimiento fue mayor durante los primeros seis meses (5.3 mm mes–1) y disminuyo a 3 mm mes–1 hasta que los juveniles alcanzaron la talla de 60 mm en un ano. El crecimiento fue maximo en febrero y minimo de julio a septiembre. Ambos modelos describieron bien el crecimiento de P. Sterna, pero el ajuste y la estimacion de los parametros fue mejor con el modelo propuesto. La gametogenesis inicio en diciembre de 2009 a una talla de 50.9 mm en los machos y 59.5 mm en las hembras; el desarrollo de la gonada fue continuo el resto del ano, con un pico de desove en febrero–marzo (~25–26 oC; 2.8 µg L–1 de clorofila a) que coincidio con el maximo del indice gonadico y la mayor talla de los ovocitos. En comparacion con ambientes subtropicales, la especie utiliza una estrategia diferente para el manejo de la energia para el crecimiento y reproduccion en un ambiente tropical; en la bahia de Acapulco P. Sterna puede alcanzar la talla optima de injerto para produccion de perlas (70–80 mm de altura de la concha) en 15–17 meses.
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annual reproductive effort of pacific winged pearl oyster pteria Sterna and its relation with the timing for planning pearl seeding operations
Journal of Shellfish Research, 2009Co-Authors: Jorge I Cacerespuig, Carlos Caceresmartinez, Pedro E SaucedoAbstract:ABSTRACT Using a combination of stereological and calorimetric methods, we studied reproductive effort of Pacific winged pearl oyster Pleria Sterna during an annual cycle in Bahia de La Paz, B.C.S., Mexico. The relationship between changes in the volumetric fraction of germinal and somatic tissues (gonad, digestive gland, adductor muscle, and mantle tissue) and changes in their energy content was analyzed. These data were also correlated with changes in water temperature and availability of food (seston). Because P. Sterna spawns several times a year, reproductive effort was estimated ∼400% in terms of energy increase from early development in October 2006 to the spawning occurring in January to February 2007. During this period, when water temperature was decreasing and seston concentration was increasing, P. Sterna followed a conservative strategy for allocating energy from reserves previously stored in somatic tissues. In contrast, when productivity dropped in spring, the species followed an opportunis...
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changes in shell dimensions of pearl oysters pinctada mazatlanica hanley 1856 and pteria Sterna gould 1851 during growth as criteria for mabe pearl implants
Aquaculture Research, 1998Co-Authors: Pedro E Saucedo, Mario Monteforte, F. BlancAbstract:The relationship between the shell dimensions of pearl oysters. Pinctada mazatlanica (Hanley 1856) and Pteria Sterna (Gould 1851). was studied to determine the possible change of form of the shell during growth. The intention was to determine the number, size and location of nuclei that could be implanted in oysters used for Mabe pearl production. Using the database of our Pearl Culture Research Programme developed in Bahia de La Paz, Mexico, we obtained measurements of 500 shells of P. mazatlanica and 500 shells of P. Sterna, representing 3 years of continuous growth under extensive culture conditions. The height-length, height-thickness and the height-weight relationships of both species were analysed, as was the height-wing length relationship for P. Sterna. There was isometric growth up to 100 mm shell height, and negative-allometric growth after 120-125 mm for P. mazatlanica. The height-thickness relationship followed a linear model, whereas the height-weight relationship was exponential. No clear allometric pattern was found in P. Sterna and all relationships fitted the power equation.
Michele Genoni - One of the best experts on this subject based on the ideXlab platform.
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new transverse plate fixation system for complicated Sternal wound infection after median sternotomy
The Annals of Thoracic Surgery, 2007Co-Authors: Andre Plass, Jurg Grunenfelder, Oliver Reuthebuch, Robert Vachenauer, Jeanmarc Gauer, Gregor Zund, Michele GenoniAbstract:Wire fixation after median sternotomy is a safe procedure, but it is still associated with potential wound infection including bony dehiscence. In case of infection and dehiscence the sternum is re-fixated with steel wires. If this is insufficient, then flap reconstruction would be another option. We describe an alternative way for complicated Sternal closure by using a rigid Sternal fixation system that is feasible for cardiac surgeons. Three patients suffering from Sternal instability and infection were operated on with the new titanium plates. The procedures were uneventful and short-term follow-up showed stable Sternal conditions. In this report the technical concept has been described in detail in 1 patient. This new Sternal fixation technique is safe and easy to handle and broadens the spectrum for closure of complicated Sternal wound infections or dehiscence.
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blood supply of the sternum and its importance in internal thoracic artery harvesting
The Annals of Thoracic Surgery, 2006Co-Authors: Denis Berdajs, Gregor Zund, Marko Turina, Michele GenoniAbstract:Background The internal thoracic artery (ITA) is the conduit of choice in coronary bypass grafting, due to the excellent long-term results achieved using it. However, increased incidence of Sternal infections after pedicled ITA harvesting has revived interest in the morphology of Sternal blood supply. Our aim was to discuss the topography of the Sternal branches with emphasis on internal thoracic artery harvesting. Methods This study was conducted on 50 fresh specimens of the anterior thorax wall. Radio-opaque material was injected and angiograms of the ITA were performed. Subsequently, the specimens were preserved and a dry dissection of each ITA and its branches was carried out. Results In dry dissected specimens, four types of vessels were identified that have the potential to carry blood to the sternum after harvesting the ITA. In the first group, the artery to the sternum also supplies the intercostal space. In the second morphologic variant, the Sternal branch gives off the perforating and anterior intercostal arteries. In the third group, we classified the common branch of the Sternal and perforating arteries. In the fourth group, the Sternal artery originated from the ITA as an independent branch. Conclusions For Sternal-intercostal, perforating-intercostal, and Sternal-perforating branches to function as collaterals after ITA harvesting, the common trunk of origin must remain intact. Based on morphologic data, we recommend ligating the common trunk as close as possible to the ITA; in this way, collateral blood flow to the sternum remains intact.
David J. Cohen - One of the best experts on this subject based on the ideXlab platform.
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randomized multicenter trial comparing sternotomy closure with rigid plate fixation to wire cerclage
The Journal of Thoracic and Cardiovascular Surgery, 2017Co-Authors: Keith B Allen, Kendra J Grubb, John Grehan, Marc W Gerdisch, Mark R Bonnell, Kevin Landolfo, Vinod H. Thourani, Nirav Patel, Yoshifumi Naka, David J. CohenAbstract:Abstract Objective To evaluate Sternal healing, complications, and costs after sternotomy closure with rigid plate fixation or wire cerclage. Methods This prospective, single-blinded, multicenter trial randomized 236 patients at 12 US centers at the time of Sternal closure to either rigid plate fixation (n = 116) or wire cerclage (n = 120). The primary endpoint, Sternal healing at 6 months, was evaluated by a core laboratory using computed tomography and a 6-point scale (greater scores represent greater healing). Secondary endpoints included Sternal complications and costs from the time of Sternal closure through 6 months. Results Rigid plate fixation resulted in better Sternal healing scores at 3 (2.6 ± 1.1 vs 1.8 ± 1.0; P P = .0007) and greater Sternal union rates at 3 (41% [42/103] vs 16% [16/102]; P P = .03) compared with wire cerclage. There were fewer Sternal complications through 6 months with rigid plate fixation (0% [0/116] vs 5% [6/120]; P = .03) and a trend towards fewer Sternal wound infections (0% [0/116] vs 4.2% [5/120]; P = .06) compared with wire cerclage. Although rigid plate fixation was associated with a trend toward greater index hospitalization costs ($23,437 vs $20,574; P = .11), 6-month follow-up costs tended to be lower ($9002 vs $13,511; P = .14). As a result, total costs from randomization through 6 months were similar between groups ($32,439 vs $34,085; P = .61). Conclusions Sternotomy closure with rigid plate fixation resulted in significantly better Sternal healing, fewer Sternal complications, and no additional cost compared with wire cerclage at 6 months after surgery.
Mario Monteforte - One of the best experts on this subject based on the ideXlab platform.
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changes in shell dimensions of pearl oysters pinctada mazatlanica hanley 1856 and pteria Sterna gould 1851 during growth as criteria for mabe pearl implants
Aquaculture Research, 1998Co-Authors: Pedro E Saucedo, Mario Monteforte, F. BlancAbstract:The relationship between the shell dimensions of pearl oysters. Pinctada mazatlanica (Hanley 1856) and Pteria Sterna (Gould 1851). was studied to determine the possible change of form of the shell during growth. The intention was to determine the number, size and location of nuclei that could be implanted in oysters used for Mabe pearl production. Using the database of our Pearl Culture Research Programme developed in Bahia de La Paz, Mexico, we obtained measurements of 500 shells of P. mazatlanica and 500 shells of P. Sterna, representing 3 years of continuous growth under extensive culture conditions. The height-length, height-thickness and the height-weight relationships of both species were analysed, as was the height-wing length relationship for P. Sterna. There was isometric growth up to 100 mm shell height, and negative-allometric growth after 120-125 mm for P. mazatlanica. The height-thickness relationship followed a linear model, whereas the height-weight relationship was exponential. No clear allometric pattern was found in P. Sterna and all relationships fitted the power equation.
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in situ growth of pearl oysters pinctada mazatlanica hanley 1856 and pteria Sterna gould 1851 under repopulation conditions at bahia de la paz baja california sur mexico
Aquaculture Research, 1997Co-Authors: P Saucedo, Mario MonteforteAbstract:Pearl oysters Pinctada mazatlanica (Hanley 1856) and Pteria Sterna (Gould 1851) were studied for an annual cycle of in situ growth from May 1992 to April 1993. Organisms generated from extensive culture were kept under repopulation conditions at Caleta El Merito. Growth measurements of shell height and length were taken monthly. Data were used to build the annual growth curve of both species, to test the temporal relationship between shell height and length, to calculate monthly and total growth rate, to follow the modal progression with the ELEFAN software, and to fit the growth curve to the Von Bertalanffy equation. Growth dimensions increased steadily during the annual cycle, from 7 to 18 months old for P. mazatlanica and from 11 to 22 months for P. Sterna. No significant differences were detected between shell height and length during growth, although length seemed to grow faster. The ELEFAN program identified two modes in P. mazatlanica (Rn= 0.205) and a single one for P. Sterna (Rn= 0.557). A positive correlation to the Von Bertalanffy equation was seen for both species (r2= 0.97 for both species).
