Revolutionary advances in organic foods.

'Organic' is a labelling term that denotes products produced under the authority of the Organic Foods Production Act. Before a product can be labelled 'organic', a government-approved certifier inspects the farm where the food is grown to make sure the farmer is following all the rules necessary to meet the US Department of Agriculture (USDA) organic standards. Companies that handle or process organic food before it gets to your local supermarket or restaurant must be certified, too. Along with the national organic standards, the USDA developed strict labelling rules to help consumers know the exact content of the food they buy. It is important to emphasise that the USDA has not made any health claims for organic foods. It is indeed fortunate that the US Department of Health and Human Services, Centers for Disease Control and Prevention, USDA and the Environmental Protection Agency are now expanding their research to explore the scientific basis for the health benefits of organic foods.

Resistance to adhesion formation: a comparative study of treated and untreated mesh products placed in the abdominal cavity.

BACKGROUND: New materials have been devised to prevent postoperative adhesions when placing a prosthesis in contact with abdominal contents. METHODS: Eighty rats underwent laparotomy and denudation of the serosa of the cecum and peritoneal covering of the abdominal wall. Five treated mesh products (Parietex Composite, Parietene Composite, Bard Composix E/X, Sepramesh, and Gore-Tex Dual Mesh) and one untreated mesh product (untreated Parietene) were randomly placed between the cecum and abdominal wall. A group without mesh was used as control. The animals were sacrificed at 21 days following surgery and analyzed for the presence of adhesions. RESULTS: The incidence of adhesion formation, mean adhesion area, maximum adhesion length, and strength of adhesion separation were similar between Parietex Composite, Parietene Composite, and Bard Composix E/X, and they were significantly less than with Sepramesh, untreated Parietene, and the control group. Gore-Tex Dual Mesh resulted in less adhesions, adhesion area, mean strength of separation, and work of separation than the untreated Parietene group and the control group. Sepramesh resulted in less strength and work of separation compared to the control group. CONCLUSIONS: The incidence of adhesions and work and strength of adhesion separation are reduced when using a treated mesh, compared to the untreated mesh and the control group without mesh. Parietex Composite, Parietene Composite, Bard Composix E/X, and Gore-Tex Dual Mesh were superior to Sepramesh, untreated Parietene, and the control group in the prevention of adhesion formation.

An instrument to measure healing in pressure ulcers: development and validation of the pressure ulcer scale for healing (PUSH).

BACKGROUND: Currently, there is no instrument that provides an accurate and simple method of monitoring pressure ulcer healing in clinical practice. This article reports the two studies that were conducted to assess the validity of the Pressure Ulcer Scale for Healing (PUSH) as a tool to monitor healing of stage II-IV pressure ulcers. METHODS: Subjects in both studies (N = 103 and N = 269) were elderly (mean Study 1, 75 years, mean Study 2, 80 years), and the majority were women (Study 1, 51%, Study 2, 70%). Study data were extracted from patients' permanent records. RESULTS: Principal components analysis confirmed that the PUSH tool accounted for 58% to 74% of the wound healing variance over a 10-week period in Study 1 and 40% to 57% of the wound healing variance over a 12-week period in Study 2. In addition, multiple regression analysis, used to measure the sensitivity of the model to total healing, showed PUSH accounted for 39% of the variance in 6 weeks and 31% of the variance over 12 weeks (p <.001; Studies 1 and 2, respectively). CONCLUSIONS: Data from these two studies confirmed that the PUSH tool, with the components of length times width, exudate amount, and tissue type, is a valid and sensitive measure of pressure ulcer healing. It is a practical approach that provides clinically valid data regarding pressure ulcer healing. Further testing is needed to confirm these findings.

Comparison of the thrombogenicity of internationally available fibrin sealants in an established microsurgical model.

Previous studies comparing the thrombotic complications of cryoprecipitated fibrin sealant containing bovine thrombin on microvascular venous anastomoses in a rat epigastric free flap model revealed deleterious outcomes regarding flap survival with higher concentrations of topical bovine thrombin. This study was designed to compare three internationally available fibrin sealants, one experimental fibrin monomer sealant that does not require thrombin, and human thrombin alone as to their effects on the survival of an established rat epigastric free flap model. Ninety Sprague-Dawley rats (400 to 600 g) were prepared for abdominal surgery, and an epigastric-based skin flap was raised. The single vein draining the flap was clamped, divided, and reconnected using standard microvascular suturing techniques. Before release of the clamps, the chosen additive was applied precisely to the anastomosis. Additional material was then added to the raw surface of the flap. The animals were divided into seven treatment groups, each receiving 1 ml of commercial or investigational fibrin sealant or human thrombin alone: one control group receiving no additive treatment, four fibrin sealant groups receiving treatment with commercial or investigational fibrin sealant preparations, and two groups receiving different concentrations (500 IU/ml and 1000 IU/ml) of human thrombin applied to the anastomoses and the surrounding tissue. Flap survival was assessed at 7 days postoperatively. This study supports the contention that microvascular free flap survival based on microvascular venous anastomotic patency was adversely effected by high concentrations of thrombin. Lower concentrations (500 IU/ml and less) of thrombin did not seem to affect flap survival. One test product was composed of a fibrin monomer sealant, which obviates the need for the thrombin additive. This group's survival rate was not statistically different from that of the control group. Thus, for microvascular anastomoses, lower concentrations of thrombin or a sealant devoid of thrombin seem to be best for microvascular anastomotic patency.

The scientific basis for selecting surgical sutures.

The purpose of this study was to examine the handling properties of synthetic absorbable and monofilament polypropylene sutures made by two different manufacturers and to compare a subjective evaluation by surgeons to the results of standardized biomechanical performance tests. The surgeons' clinical subjective evaluation of the monofilament polypropylene sutures correlated with the results of the biomechanical performance studies, whereas the biomechanical evaluation of the two synthetic absorbable sutures detected notable differences in their performance. These distinct differences in biomechanical performance of the absorbable sutures did not alter their performance in the subjective clinical evaluation.

An innovative absorbable coating for the polybutester suture.

The polybutester (PBE) suture has been coated with an absorbable polytribolate polymer that is composed of glycolide (9%), epsilon-caprolactone (51%), and poloxamer 188 (40%) to reduce its drag forces. It is the purpose of this study to document the influence of this coating on the biomechanical performance of both PBE sutures and polypropylene (PP) sutures. The performance parameters evaluated were breaking strength, elongation, stiffness, knot security, knot run down, and tissue drag. The breaking strength of PP sutures was remarkably similar to that of coated and uncoated PBE sutures. In size 5/0 PP sutures, the sutures exhibited considerably greater elongation at knot break than did comparably sized PBE sutures. The PBE suture elongated under low loads, but returned to its original length when the load was removed. In contrast, the PP suture elongated irreversibly at high loads, exhibiting creep. Coated and uncoated PBE sutures exhibited less stiffness than PP sutures and exhibited limited memory after removal from the suture package. Coating the PBE suture markedly reduced its drag forces in musculoaponeurotic, colonic, and vascular tissue. Knot security with the coated PBE suture was achieved with only one more throw than with comparably sized uncoated PBE sutures. On the basis of the results of this study, coating the PBE suture represents another major advance in suture performance.

Biomechanical performance of new cardiovascular needles.

Cardiovascular needles are now being manufactured from new stainless steel alloys containing high concentrations of nickel, Surgalloy and Ethalloy. The purpose of this study was to compare the biomechanical performance of a cardiovascular needle made of Surgalloy with a comparably sized needle made of Ethalloy. The parameters of biomechanical performance included sharpness, maintenance of sharpness, resistance to bending, and ductility. Because the biomechanical performance of these needles was remarkably similar, cardiovascular needles made of either the Surgalloy or Ethalloy alloys are recommended for cardiovascular surgery.

Revolutionary advances in skin stapling: a collective review.

The purpose of this article is to provide a collective review of the literature on skin staplers. On the basis of this review, the Auto Suture Multifire Premium, with its regular and wide metal staples, is recommended for skin closure. The Auto Suture Multifire Graftac-S is ideally suited for skin-graft fixation, because it delivers an absorbable staple that usually does not have to be removed from the healing graft. Dermal skin closure can now be achieved using the Auto Suture SQS-20, which coapts the cut dermal edges with an absorbable straight pin. Dermal wound approximation can be accomplished in significantly less time than dermal suture closure.

Fibrin sealant: a novel method of fixation for an implantable ultrasonic microDoppler probe.

While free tissue transfer affords the reconstructive microvascular surgeon the ability to provide coverage for complex wounds, the postoperative monitoring of these flaps continues to evolve. The most recent advance has been the development of an implantable microDoppler probe to provide an early warning signal for vascular obstruction. The current system relies on the use of a silicone cuff to secure a 1-mm probe to the outflow vein. The release force to remove the probe from the cuff is reported to be 1/10 of a pound (45 g). A disadvantage of this system is the need for a circumferential, relatively inelastic device around the vein. Should the cuff be too tightly secured to the vein, the potential for outflow obstruction exists. Moreover, if the probe is not well-approximated to the vein, no signal is produced. Finally, the fact that a foreign body remains in the wound after completion of the monitoring period remains a concern. The authors have investigated a new method to adhere the probe, using a commercially available fibrin sealant. The use of this biocompatible substance has the potential to obviate the need for the current method of fixation, and the associated concerns.

Quantitative swab culture versus tissue biopsy: a comparison in chronic wounds.

Soft tissue infection present a significant obstacle to the healing of chronic wounds. Historically, the gold standard for determining wound bacterial bioburden has been the quantitative tissue biopsy. Nevertheless, tissue biopsies are not universally used in today's healthcare setting. Likely reasons include damage to healing tissue, the lack of facilities to process tissue biopsies, significant pain in sensate soft tissue, and increased expense with this modality. More recently, quantitative tissue swab culture has been suggested as a means to determine the wound bioburden. The authors prospectively studied 38 patients with chronic wounds of various etiologies to evaluate the correlation between quantitative wound biopsy and swab culture. Of the 38 biopsies performed, 74% indicated infection. Simultaneous swab culture of these 28 biopsies indicated infection in 22 of the 28 cases for a correlation of 79%. The authors concluded that quantitative swab culture provides a valuable adjunct in the management of chronic wounds.

Modulation of mechanical properties in multiple-component tissue adhesives.

In vitro, ex vivo, and in vivo studies were performed to investigate the effect of mixing upon the mechanical properties of a two-component tissue adhesive. The hypothesis investigated was that a more complete mixing of the two components would yield an increase in the mechanical performance of the adhesive. This in turn would be demonstrated by improved outcomes in models of clinical sealant application. In vitro stereological analysis of tissue adhesive mixed and delivered by several different applicators demonstrated variation in the amount of mixing provided by each type of delivery system. Ex vivo tensile adhesive strength showed that there was a correlation between the amount of mixing and bonding strength; that is, more thorough mixing demonstrated higher adhesive strength. No significant difference was seen, however, between the different applicator types and impact on in vivo dermal incisional closure strength. There was a correlation, though, in amount of mixing and in vivo hemostasis. In a rabbit spleen incision model, a more thoroughly mixed sealant corresponded with a decrease in time to obtain complete hemostasis, as well as less sealant used. The effects of mixing on tissue-adhesive mechanical performance were influenced somewhat by the amount of mixing provided by the applicator. This effect, however, was dependent upon the sealant formulation and the type of in vivo application.

Ischemia-reperfusion injury in chronic pressure ulcer formation: a skin model in the rat.

Most animal models of chronic pressure ulcers were designed to study only the role of ischemic injury in wound formation, often using single applications of constant pressure. The purpose of this study was to develop and characterize a reproducible model of cyclic ischemia-reperfusion injury in the skin of small un-anesthetized animals using clinically relevant pressures and durations. Ischemia-reperfusion injury was created in a 9 cm2 region of dorsal skin in male rats by periodically compressing skin under a pressure of 50 mm Hg using an implanted metal plate and an overlying magnet. We varied the total number of ischemia-reperfusion cycles, examined the effect of varying the frequency and duration of ischemic insult, and compared ischemia-induced injury to ischemia-reperfusion-induced injury with this model. Tissue injury increased with an increasing number of total ischemia-reperfusion cycles, duration of ischemia, and frequency of ischemia-reperfusion cycles. This model generates reproducible ischemia-reperfusion skin injury as characterized by tissue necrosis, wound thickness, leukocyte infiltration, transcutaneous oxygen tension, and wound blood flow. Using this model, the biological markers of ischemia-reperfusion-induced wound development can be studied and therapeutic interventions can be evaluated in a cost-effective manner.

Evaluation of resorbable barriers for preventing surgical adhesions.

OBJECTIVE: To evaluate the ability of collagen film, collagen gel, sodium hyaluronate/carboxymethylcellulose film, and fibrin glue to prevent adhesion formation. DESIGN: Randomized trial using a rat model of a standardized abdominal wound and cecal wound. SETTING: University research laboratory. ANIMAL(S): Sprague-Dawley female rats. INTERVENTION(S): Resorbable barriers or no barrier (controls) were placed between an abdominal wall wound (1 cm x 2 cm) and a similarly sized cecal wound. MAIN OUTCOME MEASURE(S): Adhesion formation between wounds was assessed and quantitated 7 days after surgery. RESULT(S): Without treatment, 34 of 35 untreated rats (97%) developed adhesions. Treatment with collagen gel (3 of 33 rats), collagen film (3 of 10 rats), or sodium hyaluronate/carboxymethylcellulose film (2 of 10 rats) significantly reduced the incidence of adhesion formation. Treatment with fibrin sealant resulted in 9 of 10 animals having adherent wounds 7 days after surgery. CONCLUSION(S): Resorbable barriers of collagen gel, collagen films and sodium hyaluronate/carboxymethylcellulose film were effective in significantly reducing adhesion formation. Fibrin sealant at 7 days had an incidence of adhesion formation similar to that in untreated control animals.

Biomechanical performance of silicone and latex external condom catheters.

Standard in vivo biomechanical performance tests and a pilot clinical study of latex external condom catheters (ECCs) and silicone ECCs demonstrated the superior performance of the silicone ECC over that of the latex ECC. The silicone ECC has a self-adhesive that binds more securely to human skin than the self-adhesive of latex ECC. In addition, the moisture vapor transmission through silicone is significantly greater than through latex. The aggressive self-adhesive of the silicone ECC significantly reduced ECC catheter pop-off compared to that of latex ECC. Silicone ECC removal can be facilitated by the application of a warm, wet cloth to the exterior surface of the silicone ECC, which significantly reduces its self-adhesive force. Constant, gentle traction is then applied to the silicone catheter outlet end to achieve atraumatic silicone ECC removal. On the basis of the results of these standardized tests and pilot study, the silicone ECC is recommended for incontinent men without obstructive uropathy.

Evaluation of clinically applicable exsanguination treatments to alleviate venous congestion in an animal skin flap model.

This study compares the effectiveness of alleviating venous congestion with mechanically-made outlets or leech therapy in promoting skin flap survival. Free flaps of abdominal skin (3 x 6 cm) were raised on Sprague-Dawley rats and subjected to ischemic events, simulating venous congestion. Animals received 1) no treatment; 2) two treatments involving two 18-gauge needle-puncture outlets; or 3) two sessions of leech therapy. Flap perfusion was monitored with a scanning laser Doppler flowmeter. Photographic images of flaps at 7 days were assessed for areas of normal tissue (n = 15), and laser Doppler flowmeter data consisted of control (n = 6), outlet (n = 6), and leech (n = 7). Both the needle-puncture outlet (40.0% +/- 9.24%) and leech treated (34.6% +/- 7.34%) groups had a significantly greater surviving skin area than untreated control flaps (8.0% +/- 5.0%), with 2 of 15 flaps receiving mechanical outlets exhibiting > 90% surviving area. After 7 days, laser Doppler flowmeter data showed greater mean perfusion in the outlet (71.7% +/- 16.8%) and leech (92.6% +/- 17.2%) treated groups, compared to controls (15.2% +/- 10.2%). There was a significant increase in perfusion in the outlet (13.3% +/- 6.2%) and leech (9.1% +/- 1.1%) treated groups from the end of secondary ischemia to day 7 (p < 0.05) compared to controls. The results suggest that two spatially separated outlets are as effective as one leech in increasing the area of surviving skin in venous congested flaps.

Pressure ulcer assessment and management.

A pressure ulcer is an area of localized tissue destruction directly related to prolonged pressure. The loss of skin integrity produces significant consequences not only for the individual, but also for the community, with reported costs of $8.5 billion for pressure-ulcer care. Because of these costs, health care providers should be seeking prevention programs that identify high-risk individuals and implement preventive measures before the ulcer begins. Once the individual develops an ulcer, assessment of healing is critical to determine the appropriate treatment. Successful treatment depends on the principles of debridement, cleansing, bacterial control, wound dressing, and occasionally, surgical intervention.

Enhancing knot security by heat treatment of knot ears.

Heat treatment of the ears of knotted sutures markedly enhances knot security. Using coated polyester sutures commonly used in arthroscopic surgery, heat treatment of the knot ears allows secure knot construction to be achieved with a two throw granny (1 x 1) or square (1 = 1) knot. A heat source is being designed for secure knot construction in arthroscopic surgery.

Pressure ulcer debridement and cleansing: a review of current literature.

Optimal wound healing can only occur in a clean wound. Cleaning the wound of inflammatory stimuli such as devitalized tissue, reactive chemicals, and bacteria involves the procedures of debridement and cleansing. Debridement can be accomplished surgically, mechanically (wet-to-dry gauze), or chemically (autolysis or topical enzymes). Several recent studies are summarized that document the benefits of each of these techniques. Cleansing is the process of using fluid to remove loosely adherent foreign material. Numerous wound cleansing solutions and novel irrigation systems have been introduced in recent years. The potential benefits and harms of these products are discussed.

Influence of absorbable dusting powders on wound infection.

Surgical glove dusting powders are commonly used as mold-release agents and to facilitate donning. Cornstarch and CaCO3 are commonly used absorbable dusting powders. This experimental study demonstrates that these absorbable dusting powders significantly potentiate bacterial growth and enhance a wound's inflammatory response. The infection-potentiating effects of CaCO3 are significantly greater than those of cornstarch.