Patterns of Needlestick and Sharps Injuries Among Training Residents

Needlestick and sharps injuries (NSIs), a common occupational hazard for health care workers, are serious due to seroconversion risk. According to the US Centers for Disease Control and Prevention, more than 385 000 needlestick injuries occur annually among US hospital employees.¹ Current research on residents is sparse and conflicting. Needlestick and sharps injuries have been reported highest during the first postgraduate year (PGY),^2-5 but studies have relied on self-reported data or a small sample of residents in single institutions. Other investigations have not found a pattern of NSIs by PGY level.^6-8 This study systematically examined whether NSIs varied by PGY level and described patterns of NSIs among house staff.

After institutional review board approval from Mercy Health Youngstown, the NSIs reported to infection control departments by residents between January 2000 and June 2014 were reviewed. During this period, the hospital trained 924 residents. Tabulation of standard incidence rates by program, PGY level, and other variables was undertaken. Data were analyzed using χ² goodness-of-fit testing with a significance level of .05.

One hundred twenty-nine NSIs were reported (67 occurred during the first year of postgraduate education; 37 during PGY-2; 16 during PGY-3; 7 during PGY-4; and 2 during PGY-5). Incidence of NSIs among first-year residents was higher than expected (χ² goodness-of-fit statistic = 15.889 and P = .003; Figure 1). Of the 67 NSIs that occurred during the first year of training, 42 (62.7%) occurred during the first 6 months.

When NSIs were examined by program, the highest rates were found in dental residents (30.6%; 22/72) and obstetrics and gynecology residents (28.9%; 13/45). Surgery residents also exhibited a high incidence of NSIs (18.5%; 41/222). Lower incidence rates of NSIs were found among internal medicine (12.7%; 47/369) and transitional medicine (3.3%; 1/30) residents. Family medicine residents were the least likely to be injured (2.7%; 5/186).

The anatomical locations of the NSIs appear in Figure 2. Common sites for NSIs were the left index finger (19.4%; n = 24) and the left middle finger (16.9%; n = 21). The right ring finger was the least common site of NSIs (0.8%; n = 1). Left-handed NSIs were more prevalent than right-handed NSIs (80 vs 44, respectively). Five injury reports did not identify the site of the injury.

The most prevalent instrument for NSIs was the suture needle (43.4%; n = 56). Other common mechanisms were scalpels (11.6%; n = 15) and blood gas syringes (10.1%; n = 13). Sixteen source patients were seropositive for hepatitis C (12.4%); and 1 patient tested positive for hepatitis B. No cases involved human immunodeficiency virus. No seroconversion occurred in any cases.

Systematic analysis of resident experience is lacking.^3,4,6,9,10 This study, the largest nonsurvey series reported to date, adds to available knowledge on resident NSIs. The first 6 months of the intern year was the most common period for NSIs, previously unreported in the literature.

Dental residents were more likely to experience an NSI than other trainees, in contrast to literature findings that suggest surgery residents are at greatest risk.⁸ Previous literature excludes dental trainees. Dental residents may be more likely to experience an NSI based on the nature of their work (ie, the dark oral cavity with difficult illumination and learning mirrored image procedures).

Resident education and training during orientation may reduce risk. For new residents, additional procedural skill simulation using sharp instruments may decrease NSI. However, a majority of residents felt comfortable in procedures with instruments causing injury.³ Despite resident-reported mastery, caution to avoid both overconfidence and decreased attention to NSI risk is warranted.

We found that PGY-1 residents, especially during the first 6 months of training, are at greatest risk of NSI. Highest injury rates were observed for dentistry, obstetrics and gynecology, and surgery. Source patient seropositivity was low in this series. Simulation training during orientation and time-out reminders may increase procedural experience, decrease complacency, and reduce NSIs.

Corresponding Author: Thomas Marnejon, DO, St Elizabeth Youngstown Hospital, Department of Internal Medicine, 1044 Belmont Ave, Youngstown, OH 44501 (thomas_marnejon@mercy.com).

Published Online: December 7, 2015. doi:10.1001/jamainternmed.2015.6828.

Author Contributions: Dr Marnejon had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.

Study concept and design: Marnejon, Gemmel.

Acquisition, analysis, or interpretation of data: Gemmel, Mulhern.

Drafting of the manuscript: Gemmel, Mulhern.

Critical revision of the manuscript for important intellectual content: Marnejon, Gemmel.

Statistical analysis: Gemmel.

Administrative, technical, or material support: Gemmel.

Study supervision: Marnejon, Gemmel.

Conflict of Interest Disclosures: None reported.