Hepatitis B Vaccinations: Unit Size Determination Critical To Optimizing Reimbursement

If infectious disease coders correctly determine the size of the unit used in administering hepatitis B or rabies vaccines, youll optimize reimbursement and reduce administrative headaches. But its a very tricky process that requires an understanding of the nuances involved in the procedure, says Dianna Hofbeck, RN, CCM, president of North Shore Medical, Inc., in Absecon, N.J.

You can spend as much as eight hours trying to determine the reimbursement value of any given unit on any given day, Hofbeck explains. The keys to figuring out unit size, according to Hofbeck, are:

- Converting dosages (milligrams, CCs, grams) into units, since all medications and drugs must be billed in units;

- Contacting manufacturers, pharmacies or Medicare if you are unsure on unit size; and

- Keeping accurate records of prior unit determinations and their reimbursement levels, so you wont have to reinvent the wheel when you code again for the same procedure.

But the coding difficulties for hepatitis B dont end there. According to the Immunization Action Coalition, the recommended dosages for children receiving the hepatitis B vaccine vary, depending on age of the child, HBsAg status of the mother and the manufacturer. For example, the pediatric formulation for Engerix-B, manufactured by SmithKline Beecham, for 1- to 10 year-olds is 10ug, while the same formulation for recomibivax HB, manufactured by Merck & Co., is 2.5ug.

According to the Immunization Action Coalition, children who have not been vaccinated against hepatitis B in infancy may begin the series during any visit. Those who have not received three doses of hepatitis B vaccine should initiate or complete the series during the 11- to 12- year-old visit, and unvaccinated older adolescents should be vaccinated whenever possible. The second dose should be administered at least one month after the first dose, and the third dose should be administered at least four months after the first dose and at least two months after the second dose.

When you code by unit, make sure youre taking into account the total dosage administered. For example, code separately for each unit administered, whether or not the entire package or vial was utilized.

Rabies vaccines pose similar coding problems, says Carolyn Sanders, infection control coordinator at Queens Medical Center in Honolulu, Hawaii. According to Sanders, HRIB should be used in a single dose, half-infiltrated into and around the bite, with the rest given IM.

Rabies vaccine also is given as a preventative measure after suspected rabies bites or to individuals at high risk, such as veterinarians, wildlife conservation personnel and park rangers in enzootic or epizootic areas, she says. There are two types of inactivated vaccine available, but both would be given in three IM dose on days [...]

- Published on 2000-03-01