Key Practice Points
All patients with abrasions, lacerations, burns, or other wounds require a tetanus immunization history.
Tetanus occurs almost exclusively in patients with incomplete primary immunization.
Tetanus prophylaxis for wounds provides an opportunity to boost immunity for pertussis and diphtheria with Tdap (combined tetanus, diphtheria, and pertussis) vaccines.
Tetanus immune globulin (TIG) can be administered to patients with a true allergy to tetanus toxoid or patients who have not completed primary immunization, but TIG does not confer immunity for future wounds.
Local pain and swelling are the most common reactions to tetanus prophylaxis, either Td or Tdap.
Uncomplicated lacerations in otherwise healthy patients usually do not need prophylactic antibiotics.
Although there is no clear scientific evidence, prophylactic antibiotics are recommended for complicated wounds, mammalian bites, impaired host defenses, and so forth (see text).
Antibiotics should be started at the time of wound care to maximize their effect.
In recent years, community-acquired methicllin-resistant Staphylococcus aureus (CA-MRSA) has become an important cause of wound infection.
Two issues of prophylaxis arise for virtually all patients with wounds and lacerations. A careful history is taken to establish the tetanus immune status of every patient. Although nurses in most emergency departments (EDs) are required to document immune status in their notes, the ultimate responsibility lies with the physician to ensure that the patient’s tetanus prophylaxis is up to date.
Far more controversial and problematic is the issue of antibiotic prophylaxis. Despite the fact that 90% to 95% of all patients with uncomplicated lacerations do not acquire an infection, there remains an excessive use of prophylactic antibiotics. As discussed subsequently, multiple large studies have failed to support the use of prophylactic antibiotics, and they may increase the risk for infection.
For all patients with an emergency wound or laceration, a decision has to be made about whether to administer tetanus prophylaxis. Although contaminated wounds with extensive devitalized tissue are considered more tetanus-prone than are clean minor wounds, one third of documented cases of tetanus have originated from seemingly trivial injuries. A common portal of entry for tetanus is a puncture wound to the foot. The importance of tetanus prophylaxis was underscored during a shortage of immunization doses in 2001. During this period, the number of cases of tetanus increased.
Despite widespread immunization programs, 40 to 50 cases of tetanus are reported each year. Tetanus occurs almost exclusively in patients who have never been immunized or who have never completed a proper immunization program. Probably for this reason, most cases are reported in patients who are older than age 50. A high proportion of older adults, when tested for serum tetanus antibody, have been shown to have inadequate levels of protection. Young adults and children are more likely to have appropriate levels of protection because of widespread immunization programs that have been put into place in recent years. Regardless of the circumstances, a careful immunization history is taken for every patient with a minor wound. This history should establish whether initial immunization has been properly completed and should establish the date of the last tetanus toxoid dose.
When patients present for wound care, the opportunity is taken to boost immunity to diphtheria and pertussis as well as tetanus. Diphtheria, although rare, still occurs, and a diphtheria toxoid booster will help maintain immunity. Pertussis is more common, with 25,000 cases reported in 2005. In 2005, a tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis vaccine (Tdap) was approved for use in adults from ages 11 to 64 years. DTaP, which contains a higher concentration of diphtheria and pertussis than Tdap, continues to be the primary vaccination agent for children. In 2010 the Advisory Committee in Immunization Practices (ACIP) of the Centers for Disease Control and Prevention recommended that Tdap could be safely given to children from ages 7 to 10 and for adults >64 years old. Tdap is particularly important for patients <64 if they will have contact with children aged 12 months or less. These updated recommendations are reflected in Figure 21-1 . The standard interval between doses of tetanus booster is 10 years. In regions with increased risk for pertussis, this interval can be as little as 5 years (2 years in Canada), if the patient has never received a Tdap as an adult. Thereafter, Td is given at 10-year intervals. The ACIP recommends Td for pregnant women because of the lack of safety data for Tdap in pregnancy. However, if protection from pertussis is considered important, Tdap can be administered as long as the patient is made aware of the lack of that safety data.
Complications of Tetanus Toxoid and Tdap
Occasionally a patient reports an allergic reaction to a previously administered tetanus shot. In a study of 740 patients who claimed to be allergic to tetanus shots, the true incidence of allergy on skin challenge testing was low. Of the 740 patients, 7 developed local reactions that were self-limited. One patient became syncopal, and one developed a fever that lasted for 4 days. Only 1 of 740 patients had a true urticarial response but still tolerated a full immunizing dose. Despite these reassuring figures, the possibility of a serious reaction still must be considered. For patients considered at high risk for a reaction, tetanus immune globulin (250 to 500 U) is provided in the ED. Tetanus immune globulin confers immunity for that injury but not for future exposures. This preparation consists only of antitetanus antibody and does not cross-react with the toxoid. Referral to an allergist for skin testing and subsequent immunization with toxoid is recommended as prudent follow-up.
Local and systemic reactions to Td are uncommon but occur in 7% to 9% of pediatric patients. Pain, swelling, and erythema can occur at the injection site, but these reactions usually are self-limited. When Tdap and Td are compared, the safety and adverse event profiles are similar to one another. Common local symptoms include pain at the injection site, erythema, and swelling. Systemic symptoms observed in both Tdap and Td are headache, body aches, fatigue, and nausea. No cases of Guillain-Barré were observed in the safety studies.