What are the appropriate management and follow-up steps for a patient who experienced a needle stick injury to the subcutaneous part of the deltoid muscle, resulting in transient weakness of the third finger that resolved in 3 days, considering the risk of infection, nerve damage, and bloodborne pathogen exposure?

Management of Needle Stick Injury to Deltoid with Transient Finger Weakness

For a needle stick injury to the deltoid with transient finger weakness that resolved in 3 days, immediate bloodborne pathogen risk assessment and post-exposure prophylaxis take priority, while the resolved neurological symptoms suggest no permanent nerve damage requiring intervention. 1

Immediate Post-Exposure Assessment

Bloodborne Pathogen Risk Evaluation

• Classify the injury as high-risk or low-risk based on blood volume transmitted - hollow bore needles with visible blood constitute high-risk exposure requiring comprehensive prophylaxis consideration 2
• Determine the source patient's hepatitis B, hepatitis C, and HIV status immediately, as this drives all prophylaxis decisions 1, 3
• If the source is unknown or cannot be tested, assume potential exposure and proceed with risk-based prophylaxis 1

Critical Timing Considerations

• Hepatitis B immunoglobulin must be administered within 24 hours for maximum efficacy (75% protection), with declining benefit after this window 3
• HIV post-exposure prophylaxis should ideally begin within 2 hours and no later than 72 hours after exposure 2
• Hepatitis B vaccine can be given simultaneously at a different injection site without interference 3

Post-Exposure Prophylaxis Protocol

For High-Risk Injuries (Hollow Bore Needle with Blood)

Hepatitis B Management:

• If the victim lacks documented hepatitis B immunity, administer hepatitis B vaccine immediately 3, 2
• Add hepatitis B immunoglobulin (0.06 mL/kg IM in deltoid or lateral thigh) if the source is HBsAg-positive or belongs to a high-risk group 3
• Never inject immunoglobulin intravenously or into the gluteal region due to serious reaction risk and sciatic nerve injury risk 3

HIV Prophylaxis:

• Initiate antiretroviral post-exposure prophylaxis only for high-risk injuries with HIV-positive source or source from high-risk group 2
• Consultation with infectious disease specialist is recommended for antiretroviral regimen selection 1

Hepatitis C Monitoring:

• No prophylaxis exists for hepatitis C; perform baseline and follow-up testing at 3-6 months for high-risk exposures 2

For Low-Risk Injuries

• Only hepatitis B prophylaxis measures need consideration 2
• Hepatitis C and HIV prophylaxis are not indicated 2

Tetanus Prophylaxis

• Administer tetanus toxoid booster if more than 5 years since last dose, as needle stick injuries are considered contaminated wounds 1, 4
• Tdap is preferred over Td if not previously administered 5

Neurological Symptom Interpretation

Transient Finger Weakness Analysis

• The 3-day resolution of third finger weakness suggests transient neuropraxia rather than structural nerve damage - no surgical intervention is indicated 6
• Deltoid injection site is anatomically distant from median/ulnar nerve distributions controlling finger function, suggesting the weakness was likely vasovagal or anxiety-related rather than direct nerve trauma 6
• No electrodiagnostic studies or nerve imaging are warranted given complete spontaneous resolution 6

Wound Care and Infection Prevention

• Wash the injection site immediately and thoroughly with soap and water 1
• Do not recap, bend, or break the needle - this increases risk of additional injury 1
• Dispose of the needle in a puncture-resistant sharps container immediately 1

Follow-Up and Monitoring

• Document the incident formally according to OSHA requirements 1
• Schedule serological follow-up testing at 3 and 6 months for hepatitis C and HIV if high-risk exposure occurred 2
• Monitor the injection site for signs of local infection (redness, swelling, warmth, purulent discharge) over the next 48-72 hours 4

Common Pitfalls to Avoid

• Do not delay hepatitis B immunoglobulin beyond 24 hours - efficacy drops significantly after this window 3
• Do not assume the source is negative without testing - proceed with risk-based prophylaxis if source status is unknown 1, 2
• Do not pursue neurological workup for completely resolved transient symptoms - this represents unnecessary healthcare utilization 6
• Do not inject hepatitis B immunoglobulin into the gluteal region due to sciatic nerve injury risk 3