A needle remover is a device used to physically remove a needle from a syringe. In developing countries, there is still a need for improvements in needle safety in hospital settings as most of the needle removal processes are done manually and under severe risk of hazard from needles puncturing skin risking infection. These countries cannot afford needles with individual safety devices attached, so needle-removers must be used to remove the needle from the syringe. This lowers possible pathogen spread by preventing the reuse of the syringes, reducing incidents of accidental needle-sticks, and facilitating syringe disposal.
Background
In regions surveyed by the World Health Organization (WHO) in the early 2000s, the reported number of needle-stick injuries in developing world countries ranged from .93 to 4.68 injuries per person and per year, which is five times higher than in industrialized nations.Department of Essential Health Technology. (2004). Proposed Agenda to Evaluate the Risks and Benefits Associated with Using Needle-Removing Devices. Retrieved October 22, 2005. Needle-stick injuries are further complicated by disease transmission, such as Hepatitis B, Hepatitis C and HIV. In Ghana, a study of 803 schoolchildren revealed that 61.2% had at least one marker of hepatitis B virus.Sagoe-Moses, C., et al. (2001, August 16). Sounding Board: Risks to Health Care Workers in Developing Countries . N Engl J Med 345 (7): 538–541. As a result, health care workers, patients, and the community in developing nations are at an increased risk of contracting blood-borne pathogens via the reuse and improper disposal of needles, and accidental needle-sticks.Harner, C. (2004, October). Needle Remover Device Design Transfer Package. Retrieved September 7, 2005.
In the U.S., the Needlestick Safety Act signed in 2000 and the 2001 Bloodborne Pathogens Standard both mandated the use of safety devices and needle-removers with any sharps or needles.Jagger, J., De Carli, G., Perry, J., Puro, V., Ippolito, G. (2003). Chapter 31: Occupational Exposure to Bloodborne Pathogens: Epidemiology and Prevention. Prevention and Control of Nosocomial Infections (4th Ed). Lippincott, Williams, and Wilkins; pp. 27-28 As a result, there was a large increase in research, development, and marketing of needle safety devices and needle-remover. In most hospital and medical settings in the U.S., needle safety regulations are maintained through individual needle safety devices and needle disposal boxes.
Existing solutions One of the most common causes of needle-stick injuries, which the Needlestick Act and Bloodborne Pathogens Standard were attempting to decrease, was two-handed recapping.Wilburn, S. (2004). Preventing Needlestick Injuries among Health Care Workers: A WHO-ICN Collaboration. Int J Occup Environ Health 10:451-456. As a result, a one-handed capping mechanism was added to insulin and tuberculin syringes. The cap is attached to the syringe via a hinge, which allows the cap to be snapped onto the needle using one hand. The disadvantage to the hinge system is that the cap can get caught by jewelry and clothing, can get bumped when used, and the fixed position can be a hindrance during low angle injection. So Becton Dickinson (BD) has recently come out with a variation on this safety: instead of a hinge, the device slides over the needle and fully covers the tip of the needle, so accidental needle-sticks do not occur.Becton, Dickinson, and Company. (2004). BD SafetyGlide Syringe for Insulin, TB, and Allergy: Quick Reference Card. Retrieved October 23, 2005.
However, the rest of the world does not have similar needle and syringe regulations. For instance, the WHO is only able to regulate vaccinations in developing countries by ensuring that all vaccination syringes sent to these countries have autodisable features, since the major concern is the reuse of contaminated needles and syringes. These autodisable features allow the syringes to only be used once, so they cannot be reused. These mechanisms could be teeth that interlock to prevent the plunger from being pulled back for another use or a bag prefilled with the vaccine to stop reuse. For example, the SoloShot has a metal clip that locks the plunger down after one use.International Council of Nurses. (2005). Nursing Matters fact sheet. “First Do No Harm: Auto-Disable Syringes for Immunization Safety” . Retrieved October 22, 2005. The BD Uniject is a prefilled vaccine syringe that uses a plastic bulb instead of a plunger and has a disc valve to prevent reuse.Becton, Dickinson, and Company. (2005). BD Uniject: Prefill Injection Device. Retrieved October 23, 2005. Still, over 90% of syringes worldwide do not have autodisable features. Individual protection devices are expensive, and regular needles are much more prevalent. Consequently, many developing world countries use needle-removers to reduce the risk of disease transmission via these exposed.
Benefits of needle-removers Needle-removers minimize the occurrence of accidental needle-sticks because they allow immediate removal and containment of the needles, especially if the device is near the area of use. Reuse of syringes is prevented because the needle-remover physically separates the needle from the syringe, making the syringe useless. They also improve waste disposal by decreasing both the amount of infectious waste and the amount of safety boxes needed for the waste, since safety boxes can pack syringes 20-60% more compactly without the needles. Additionally, these devices are cost-efficient since one device can handle several hundred needles. Many developing world countries do not have the resources to afford auto-disable syringes, so with needle-removers, the hospitals can continue to use cheap syringes, while only paying a one-time fee to buy a needle-remover that has a life-span of about 200-500 needles.
Social and ethical implications A significant ethical issue for the project is whether or not the needle-remover will cause more harm than its potential benefits. Engineers are obliged to use their skills and knowledge to improve the safety, health, and welfare of the public.Biomedical Engineering Society. (2004). Code of Ethics. The main concern is for the operator of the device; no engineer should create a device that could injure the operator. Another concern is that children may gain access to the device and accidentally hurt themselves. If a device design could potentially cause either of these problems, the team would be ethically obligated to reexamine that design, and it would either have to be improved or abandoned. When the device functions effectively and safely, it will serve to protect the welfare of the community. In developing countries, the risk of disease transmission is elevated due to the high percentage of needle-stick injuries, which is a result of inadequate needle collection devices. Increased pathogen transmission also occurs from the reuse of contaminated needles when supplies are low. The device will prevent reuse of needles and facilitate needle collection and disposal, and thus will improve the health and safety of hospital workers and the community.
The social and economic effects of the device also need to be recognized. In developing countries, the lack of proper needle collection devices leads to an increase in the number of occupational needle-sticks by health care workers via contaminated needles. Occupational needle-sticks account for 40%-65% of Hepatitis B and C infections in health care workers.Prüss-Üstün A., Rapiti E., Hutin Y. (2003). Sharps injuries: global burden of disease from sharps injuries to health-care workers. Geneva, World Health Organization (WHO Environmental Burden of Disease Series, No. 3). As a result, more health care workers have to undergo post-exposure testing and treatment, both of which cost money for the hospitals and the countries. There is also the manpower cost associated with losing trained health care workers to infections acquired on the job. With fewer than 10 doctors for every 100,000 individuals in sub-Saharan nations, any loss of hospital staff puts a strain of hospital resources. In addition, developing countries have made significant investments in training their health care workers, which is lost when occupational needle-sticks cause health care workers to leave the medical field.
The economic considerations are not just limited to costs associated with health care workers. Due to the high cost of needle-disposal containers and the fact that the containers usually have to be shipped overseas, unsafe and dangerous substitutes are used instead. This practice can potentially lead to needle-sticks by health care workers and individuals in the community, as well as needle reuse by members of the community, which can increase the potential spread of diseases.
Possible designs The easiest needle-removers to operate are electrically powered, and either melt the needle or cut the needles at multiple sections. One patented design involves a syringe falling down into a chamber where powered movable blades advance the syringe onto fixed blades on the opposite side, at which point the syringe is cut with a shearing motion at multiple points.Garvis, M. and Beer, M. (1974, April 2). Patent #3800644: Destruction and Disposal Device for Hypodermic Syringes and the Like. Retrieved October 17, 2005. There are other patents that use electricity between electrodes or between rotating gears to short-circuit the needle and melt it off the syringe.Ch’ing-Lung, H. (1986, December 9). Patent #4628169: Mini Electrical Syringe Needle Destroyer. Retrieved October 17, 2005.Hashimoto, T. (1990, October 9). Patent #4961541: Apparatus for Disposing of a Used Hypodermic Syringe. Retrieved October 17, 2005. A more complex design involves a hammer mill and grinder to break up and grind up the plastic and metal parts of the syringes, after which, the pieces are heated and cooled. The end result is metal particles encapsulated in a piece of plastic.Wallace, A. et al. (1991, September 10). Patent #5046669: Syringe Disposal Apparatus and Method.