To the Editor—The Massachusetts Department of Public Health mandates that all Massachusetts hospitals maintain an active log to track sharps injuries due to the health risks related to such injuries.Reference Laramie, Pun, Fang, Kriebel and Davis ¹ These logs are used to guide continuous quality improvement activities aimed at preventing sharps injuries. A review of sharps injuries at UMass Memorial Medical Center (UMMMC) in 2013 showed a seemingly high incidence occurring among healthcare workers who were administering local anesthesia. We undertook an investigation of the relative rate of needlesticks associated with local anesthesia administration compared to the rate of all sharps injuries over a 10-year period.

A review was performed of all reported sharps injuries at UMMMC recorded in the Employee Health Services log between January 1, 2004 and December 31, 2013, including the setting of the event and the activity performed. Sharps injuries were categorized as 1 of 5 types: local anesthesia needlesticks, insulin needlesticks, other hollow-bore needlesticks (excluding local anesthesia and insulin sticks), suture injuries, and scalpel injuries. Sharps injuries per 1,000 employees were calculated using the total number of employees, residents, and medical students per year. Sharps injury rates per 10,000 inpatient days were also calculated using the total inpatient admissions, ambulatory visits, and emergency department visits per year. We used descriptive statistics, test of trend, and U statistical process control charts to describe the sharps injury incidence over time.

There was a statistically significant decrease in overall sharps injuries per 1,000 employees from 2004 to 2013 (P=.003) (Table 1). In contrast, sharps injuries associated with local anesthesia needlesticks showed a statistically significant increasing trend from 2004 to 2013 (P=.017). Other hollow-bore needlesticks showed a statistically significant decreasing trend from 2004 to 2013. The incidence of insulin needlesticks, suture injuries, and scalpel injuries showed no significant trend from 2004 to 2013. Comparable trends are shown with calculated rates per 10,000 inpatient days.

Table 1 Sharps Injuries per 1,000 Employees

Accidental sharps injuries put healthcare workers at risk for >20 pathogens, including HIV, hepatitis B, and hepatitis C.Reference De Carli, Abiteboul and Puro ^{2 , 3} In addition to the concern for healthcare workers well-being, exposure management incursa significant cost to healthcare, with cost estimates of well over $100 million annually in the United States.Reference Leigh, Gillen, Franks, Sutherland, Nguyen and Steenland ^{4 ,} Reference Adib-Hajbaghery and Lotfi ⁵ Consequently, continued efforts to identify and eliminate the causes of sharps injuries are essential.

Sharps injuries can result from the exchange of sharps between healthcare workers, the placement of sharps in the disposal container, or nonadherence to the sharps injury prevention protocol.Reference Laramie, Pun, Fang, Kriebel and Davis ^{1 ,} Reference Jagger, Hunt, Brand-Elnaggar and Pearson ^{6 ,} Reference Bi, Tully, Pearce and Hiller ⁷ Sharps injury can be prevented by eliminating unnecessary sharps use, the use of sharps injury prevention devices, the practice of safer work environments, and continuous training of healthcare workers regarding proper technique and safety.Reference Laramie, Pun, Fang, Kriebel and Davis ¹ Data from the Massachusetts Department of Public Health have shown an ongoing decline in sharps injuries across all Massachusetts hospitals that correlates with the introduction of these approaches.Reference Laramie, Pun, Fang, Kriebel and Davis ^{1 , 8}

Practices that have been linked to healthcare worker injuries from hollow-bore needles include not properly recapping the needle, lack of awareness of needle location in relation to oneself, and/or not activating safety mechanisms to cover the tip of the needle.Reference Jagger, Hunt, Brand-Elnaggar and Pearson ^{6 ,} Reference Bi, Tully, Pearce and Hiller ⁷ An association between the administration of local anesthesia and sharps injuries has not previously been noted, but it is reasonable to consider that it relates to the procedure used to administer local anesthesia. To administer local anesthesia, the healthcare worker commonly draws up excess local anesthesia in to a syringe, performs an initial injection of local anesthetic, places the needle and syringe down with or without capping the needle, and then reuses the same needle and syringe to administer additional doses of local anesthesia as needed to obtain adequate analgesia for a subsequent procedure. Therefore, the safety mechanism on the needle and syringe are not activated after the first use, and healthcare workers may become injured when recapping the needles or by being unaware of the needle location.Reference Jagger, Hunt, Brand-Elnaggar and Pearson ⁶

The reasons for the increase in the incidence of injuries associated with local anesthesia administration at our institution is not clear. It is possible that these events were underreported in the past, and that more accurate reporting occurred in relation to the overall decrease in the rate of sharps injuries. Strengths of this study include the study population and duration: our analysis included sharps injuries over 10 years at a large academic medical center and included events in both the inpatient and outpatient settings. Two limitations of this study are the retrospective study design and its setting in an academic medical center, which may not be generalizable to other settings.

In summary, we report a previously unidentified risk factor for sharps injuries, the administration of local anesthesia by healthcare workers. Further research is needed to develop effective counter measures to prevent these injuries.