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Three Part Question

In[a person that has had a needlestick injury] does [a bleeding injury site compared with a non-bleeding injury site or the presence of visible blood on the device] increase [the risk of contamination by blood borne viruses].

Clinical Scenario

A worried 21 year old student accidentally walked into an intravenous drug user not long ago at a party. On questioning her about the circumstances surrounding the exposure we wondered if the presence of visible blood on the device or a bleeding injury site would increase the risk of transmission of blood bore viruses.

Search Strategy

Medline 1966-July 2006 using the OVID interface.
[blood exposure.tw or needlestick$.tw or needle?stick.tw or EXP needlestick injuries/] AND [HIV.exp or HBV. exp or HCV exp] AND [visible blood.mp or seroconversion or transmission.exp or blood exposure. exp]

Search Outcome

13 papers found, 6 papers relevant, 3 papers used, 2 citations

Relevant Paper(s)

Author, date and country	Patient group	Study type (level of evidence)	Outcomes	Key results	Study Weaknesses
Satcher D. 1995 USA, UK, France	Health care workers (HCW) after percutaneous exposure to HIV	Retrospective case-control study	HIV tramsmission	31 case-HCW and 679 Control-HCW were examined using logistic regression analysis. Based on this analysis, factors associated with HIV transmission included deep injury 16.1 adjusted odds ratio (OR) and 6.1-44.6 confidence interval (CI), device visibly contaminated with the source patient's blood 5.2 OR, 1.8-17.7 CI, procedures involving a needle placed directly in the vein or artery 5.1 OR, 1.9-14.8 CI, and terminal illness in the source patient 0.2 OR, 0.1-0.6 CI. All OR were significant at p<0.01	Information on terminal illness in the source patient and visible blood on the device was missing for 19% of case-HCW and 48% control-HCW, and 3% of case-HCW and 6% control-HCW respectively. Reporting bias with exposures perceived to be more likely to result in HIV transmission reported , ascertainment bias. Number of case-HCW was small

Comment(s)

Health care workers and members of the public are potentially at risk for HIV, HBV and HCV through occupational and community exposures to blood or contaminated sharp devices respectively. Although prospective studies have indicated that the risk for HIV, for example is 0.3%, there are other factors that influence this risk. Some of these factors include deep injury, a device visibly contaminated with blood, procedures involving a needle placed directly in the vein or artery and terminal illness in the source patient.Therefore the type of exposure may be used to assess the risk of transmission of BBVs following the presentation of a person with a needle stick injury in the emergency department. This will also be useful to determine which protocol to follow i.e. selection of serological tests for assessment, initiation of PEP and providing follow-up.

Clinical Bottom Line

In any person who has sustained a needlestick injury, the presence of visible blood on the device compared with the absence of visible blood on the device or a bleeding injury site does increase the risk of contamination by blood borne viruses specifically HIV, HBV and HCV.

References

1. Satcher D. Case-control study of HIV seroconversion in health care workers after percutaneous exposure to HIV-infected blood. France, UK,USA. Jan 1988-Aug 1994. Morbidity and mortality weekly report. Dec 22 1995.Vol 44: No 50