Biomedical subjects

J G Thacker

Publications and source records attributed to J G Thacker.

At least 91 records · Page 5Linked to original sources

PubMed1975

Mechanical performance of surgical sutures.

A comprehensive analysis of the mechanical performance of sutures has been made to provide information concerning the reliability and security of knotted sutures. The tests utilized in this analysis were designed to be easily reproduced by other investigators. The construction of the knot and the knot performance analysis were undertaken utilizing an Instron Tensile Tester. The mechanical reliability of each knotted suture was determined by measuring the number of throws to reach knot break, the expected slippage of the knot when it reaches knot break, and the maximal holding force at knot break. On the basis of these measurements, recommendations are made for the use of a suture at operation.

Biomechanical Phenomena↗

PubMed1975

Wound cleansing by high pressure irrigation.

All traumatic wounds are contaminated to some degree by both soil and bacteria. Specific infection potentiating factors in soil impair the defenses of the tissue and invite infection. These factors are small in size and resist removal by low pressure irrigation. The efficiency of wound irrigation is markedly improved by delivering the irrigant to the wound under continuous high pressure. Irrigation of the wound with saline solution delivered at 15 pounds per square inch removed 84.8 per cent of the soil infection potentiating factors from the wound. The residual infection potentiating factors remaining in the wound did not significantly impair tissue defenses. On the basis of these experimental studies, clinical studies are now being initiated to test the therapeutic value of high pressure irrigation in traumatic wounds in humans.

Animals↗

PubMedDate not supplied

Influence of cutting edge configuration on surgical needle penetration forces.

A standardized test for measuring the needle penetration forces has been developed that can be easily replicated in any laboratory. Using this test, conventional cutting edge needles utilized in the test produced lower penetration forces than reverse cutting edge needles. The lower penetration forces encountered by the conventional cutting edge needles imply that the physician should be able to handle these needles with more dexterity and precision than the reverse cutting edge needle.

Membranes, Artificial↗

PubMedDate not supplied

Emergency physician's needle holder.

A new needle holder is described that has jaws metallurgically bonded with tungsten carbide particles that enhance needle holding security without causing sutural damage during instrument ties. Scissors have also been incorporated into the needle holder to cut sutures. One ringlet on a handle has been offset to facilitate retrieval of the needle holder from a flat surface.

Emergency Medicine↗

PubMedDate not supplied

Biomechanics of a new atraumatic surgical needle holder.

It is the purpose of this report to design, develop, and evaluate a needle holder whose jaws improve needle-holding security without altering the geometry of the curved surgical needle. The configuration of the jaws of this new needle holder is curved, conforming to the curvature of the surgical needle. A biomechanical study of this curved surgical needle holder demonstrates that it holds the curved needle securely without needle deformation.

Biomechanical Phenomena↗

PubMedDate not supplied

Influence of knot configuration and tying technique on the mechanical performance of sutures.

The purpose of this investigation was to determine the influence of knot configuration and tying technique on the mechanical performance of surgical sutures. Multifilament and monofilament nylon sutures were selected for this evaluation because they are commonly used in wound closure. The mechanical performance of these sutures was judged by the following parameters: knot breakage force, configuration of secure knots, and knot run down force. During each test, tension was applied at either rapid or slow rates, which correlates with the physician's speed of tying knots. On the basis of these mechanical performance tests, four throw square (1 = 1 = 1 =1) knots and five throw square (1 = 1 = 1 = 1 = 1) knots are recommended for monofilament nylon and multifilament nylon sutures, respectively, in which the speed of application of forces to the knots is relatively slow. Because these tests can easily be replicated in any laboratory, manufacturers now have a scientific basis for recommending specific tying techniques for their surgical sutures.

Physical Phenomena↗

PubMedDate not supplied

Biomechanical performance of laser-drilled and channel taper point needles.

The purpose of this study is to evaluate the biomechanical performance of laser-drilled and channel needle swages. The laser-drilled swages have a more uniform circumference that encounters lower drag forces than the channel needle swages. In addition, the length of the laser-drilled hole is shorter than that of the channel needles, allowing the physician to grasp the laser-drilled needle close (3 mm) to the needle end without deformation. These benefits of laser-drilled swages indicate that they should replace all channel needles.

Biomechanical Phenomena↗

PubMedDate not supplied

Influence of emergency physician's tying technique on knot security.

The purpose of this study was to determine the influence of emergency physician's tying technique on knot security using 2-0 and 4-0 monofilament and multifilament nylon sutures. Using an Instron Tensile Tester and a portable tensiometer, knot security was achieved with these sutures using four-throw square knots (1 = 1 = 1 = 1). After didactic and psychomotor skill training, medical students were taught to construct the four-throw square knot using either a two-hand tie or an instrument tie. Using the portable tensiometer, their knot tying techniques were judged to be superior to those used by emergency physicians. The emergency physician's faulty technique can easily be corrected by didactic information and psychomotor skill training.

Emergency Medicine↗

PubMedDate not supplied

New, innovative packaging system for surgical sutures and needles.

A new, innovative packaging system for surgical needles and sutures has been developed that meets the special needs of emergency physicians, surgeons, and operating personnel. This packaging system consists of an overwrap, or breather pouch, as well as an innerwrap containing the needle swaged to a surgical suture. The flaps of the overwrap are offset and serrated to facilitate the opening and sterile transfer of the inner packet to the sterile field. The inner packet contains either a plastic labyrinth or craft board that maintains the suture as straight as possible until knot construction. The needle swaged to a suture is parked in foam to protect its sharp cutting edges and point.

Emergency Service, Hospital↗

PubMedDate not supplied

Biomechanical performance of microsurgical spatula needles for the repair of nail bed injuries.

The purpose of this study was to determine the mechanical performance of microsurgical spatula needles for repair of nail bed injuries. Standard biomechanical tests have been devised to evaluate the performance of microsurgical spatula needles. Two comparable groups of microsurgical spatula needles were selected from two different manufacturers for these biomechanical studies. The results of this testing demonstrated that needle point geometry and needle composition were important determinants of needle performance. When needles of comparable size were evaluated, the biomechanical performance of the CS160-8 spatula needle (Ethicon, Inc., Somerville, NJ) was superior to the C-5 spatula needles (Alcon, Inc., Fort Worth, TX). While the development of these biomechanical tests has allowed the evaluation of these microsurgical spatula needles, these same tests can be used to assess the performance of new microsurgical spatula needles.

Alloys↗

PubMedDate not supplied

Ease of donning surgical gloves: an important consideration in glove selection.

It is a commonly held belief among physicians that powder free surgical gloves are more difficult to don than cornstarch powdered gloves. This difficulty is supposedly enhanced when the physician's hands are wet, a situation commonly encountered when regloving during surgical procedures. This investigation dispels these beliefs by demonstrating that the forces required to don powder free gloves do not differ significantly from those required to don gloves coated in cornstarch lubricant. Moreover, Biogel, a new powder free glove with an inner hydrogel lining, is shown to don easily and safely without ripping, even with wet hands, a circumstance not encountered with other gloves.

Emergency Medicine↗

PubMedDate not supplied

A new glove puncture detection system.

A new glove detection system has been developed for early and accurate detection of a hole in the glove. It consists of an inner glove colored by a green dye and outer glove. When a breach in the outer glove occurs, the inner glove develops a dark patch around the needle puncture hole, a visible indicator for immediate glove change. Using a computerized needle penetration system, the immediate and maximal penetration forces as well as the work required for needle penetration of this new double glove was significantly greater than those encountered with either the inner or outer glove tested separately. In addition to hole detection, this double glove provides increased protection against needle penetration.

Coloring Agents↗

PubMedDate not supplied

A new powder-free glove with a textured surface to improve handling of surgical instruments.

A latex surgical glove has been designed to have a textured surface that stimulates the surface of intact skin. This textured surface enhances security of grasp of surgical instruments under wet and dry conditions without altering tactile discrimination. The unique hydrogel polymer of this glove allows the glove to be donned with either wet or dry hands without the use of cornstarch lubricants.

Evaluation Studies as Topic↗

PubMedDate not supplied

Another cause of surgical needle holder damage to surgical sutures.

The sharp edges of the box lock of the needle holder can inadvertently damage the suture during instrument ties. Compression of a monofilament nylon suture between the sharp edges of the box lock of a surgical needle holder damages the suture, reducing its breaking strength. This adverse effect has been eliminated by one manufacturer whose needle holder box lock has rounded edges and sufficient space to permit passage of the suture.

Equipment Design↗

PubMedDate not supplied

Enhancing needle durability by silicone coating of surgical needles.

The purpose of this study was to assess the effect of coating surgical needles with silicone on their durability. Needle durability is a measure of needle sharpness after repeated passage through tissue. Needle sharpness was determined by quantitating the energy required to pass a designated needle repeatedly (20 times) through porcine skin, linea alba, colon, and aorta. The results demonstrate that the durability and sharpness of silicone-coated needles were significantly greater than those of comparable uncoated needles in linea alba, colon, and aorta, but not in skin.

Animals↗

PubMedDate not supplied

Biomechanical performance of cutting edge surgical needles.

The purpose of this study was to compare the biomechanical performance of cutting edge needles made of S45500 stainless steel alloy to Surgalloy stainless steel. The new high-nickel stainless steel alloy, Surgalloy, has superior performance characteristics over that of the other high-nickel stainless steel alloy, S45500. The Surgalloy needle is produced from a stronger stainless steel alloy than the S45500 needle. The Surgalloy needle has considerably greater resistance to bending than the needle produced from S45500 alloy. In addition, Surgalloy stainless steel has almost a twofold greater resistance to fracture than the S45500 stainless steel alloy.

Biomechanical Phenomena↗

PubMedDate not supplied

Inadequate standard for glove puncture resistance: allows production of gloves with limited puncture resistance.

The National Fire Protection Association has developed standards for glove puncture resistance using a metal puncture probe. Biomechanical performance studies have demonstrated that glove puncture resistance to the probe is significantly greater than that of the hypodermic needle, suggesting that these standards have no clinical relevance. These standards give a false sense of security to health care personnel and sanction the production and use of gloves that give inadequate protection. The result is potentially harmful for medical personnel.

Equipment Design↗

PubMedDate not supplied

Biomechanical performance of powder-free examination gloves.

Biomechanical performance studies were undertaken for powder-free, latex and nitrile examination gloves. Using standardized tests, examination glove performance was judged by measuring glove thickness, glove puncture force, glove tape adhesion force, glove donning force, glove stiffness, and immediate unrecovered stretch. Even though the nitrile examination gloves were thinner than the latex examination gloves, they exhibited a greater puncture resistance. In addition, tape adherence to the N-Dex nitrile glove was the lowest. Moreover, measurements of the handling characteristics of the nitrile examination gloves demonstrated that they are an acceptable alternative to latex examination gloves. While these biomechanical studies demonstrate the superiority of the nitrile examination gloves, clinical glove evaluation is still needed to determine their performance in the health care setting.

Biomechanical Phenomena↗