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Extensive clinical investigations have demonstrated that double-gloves and blunt-tipped surgical needles dramatically reduced the risk of accidental injuries during surgery. During the last decade, double-glove hole puncture indication systems have been developed that reduce the clinical risk of accidental needlestick injuries as well as detect the presence of glove hole puncture in the presence of fluids. When the outer glove is punctured, the colored underglove becomes apparent through the translucent outer glove, necessitating glove removal, hand washing, and donning of another double-glove hole puncture Indicator system. This article presents the first biomechanical performance study that documents the puncture resistance of blunt surgical needles in latex and nonlatex single gloves and double-glove hole puncture indication systems. The technique for measuring glove puncture resistance simulates the standard test for material resistance to puncture outlined by the American Society for Testing and Materials. The maximum puncture resistance force was measured by the compression load cell and recorded in grams with a strip chart recorder. Ten puncture resistance measurements for the taper point needle, blunt taper point needle, and blunt needle were taken from five samples of the Biogel Indicator underglove, Biogel Super-Sensitive glove, Biogel glove, Biogel Skinsense N Universal underglove, and Biogel Skinsense Polyisoprene glove; and the Biogel, Biogel Super-Sensitive, and Biogel Skinsense Polyisoprene double-glove hole puncture indication systems. The magnitude of puncture resistance forces recorded was influenced by several factors: glove material, number of glove layers, and type of surgical needle. For each type of curved surgical needle,the resistance to needle penetration by the nonlatex gloves was significantly greater than those encountered by the latex glove materials. The resistance to needle puncture of all three double-glove systems was significantly greater than that of either the nonlatex or latex underglove or outer glove. The taper point needle encountered the lowest puncture resistance forces in the five single gloves and the three double-glove systems. Blunting the sharp end of the taper point needle markedly increased its resistance to glove puncture in the five single gloves and five double-glove systems. The blunt-point surgical needle elicited the greatest needle penetration force in all of the single and double-glove systems.

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.

A mechanical performance test using an Instron Tensile Tester demonstrated the superior handling characteristics of Surgipro suture as compared to Prolene suture that facilitated knot construction without suture breakage. For both granny and square knots, the knot run down forces for the Surgipro sutures were significantly less than those encountered for comparable knots for Prolene sutures. This propensity of the two-throw knots of Surgipro sutures to advance without breakage considerably facilitated knot construction.

The purpose of this study was to correlate the latex gloves' susceptibility to hydration to its development of glove expansion or irreversible elongation of the latex glove. During hydration, the Micro-Touch glove exhibited significantly more creep strain than did the Biogel gloves. Similarly, the Micro-Touch glove exhibited glove growth, while the Biogel glove maintained a uniform fit during hydration.

Needle performance is primarily judged by its penetration through tissue. For detailed studies of needle performance, tissue is too heterogeneous and unstable and difficult to obtain. A homogeneous, stable, and readily available polyurethane substrate has been evaluated as a suitable alternative to biological tissue for evaluation of needle penetration. The needle penetration profiles through the synthetic substrate correlated very well with those through natural tissue. In addition, the synthetic substrate was sensitive enough to easily detect a 20% increase in the force necessary to penetrate natural tissue. This polyurethane substrate offers a valid alternative to biological tissue for the testing of needle penetration performance.

Because needle bending resistance is such an important factor in the selection of surgical needles, a standard quantitative test of needle bending has been devised to study the biomechanics of deformation of needles from three different commercial manufacturers. The superior resistance to deformation of needles made by one manufacturer has been related to the specific alloy, ASTM 45500 stainless steel, employed in its production. The needles produced from ASTM stainless steel 45500 have stronger tensile and yield strengths than those of the other alloys, accounting for their greater resistance to bending.

The performance characteristics of four 24-inch wheelchair tires are considered; one pneumatic and three airless. Specifically, two new airless polyurethane foam tires (circular and tapered cross-section) were compared to both a molded polyisoprene tire and a rubber pneumatic tire. Rolling resistance, coefficient of static friction, spring rate, tire roll-off, impact absorption, wear resistance, and resistance to compression set were the characteristics considered for the basis of comparison. Although the pneumatic tire is preferred by many wheelchair users, the two new polyurethane foam tires were found to offer a performance similar to the high-pressure pneumatic tire. In addition, the foam tires are less expensive and lighter in weight than the other tires tested.