u
E
TH RAPY
J Oral Maxillofac Surg 48 :617-620, 1990
Antibiotic Prophylaxis Against Wound Infections in Oral and Maxillofacial Surgery LARRYJ.PETERSON, DDS· The prevention of wound infection is one of the major goals of every surgeon. When infection does occur, increased patient morbidity and suffering result, with consequent additional expense, increased antibiotic usage, and a delayed recovery. Over the last tOO years, principles of infection prevention have been clearly defined which, when applied, can reduce infection rates to ncar zero. The purpose of this article is to delineate these principles and apply them to the variety of surgical procedures the oral and maxillofacial surgeon is called upon to perform. Infection occurs when there is a significant quantitative and qualitative bacterial insult; it occurs more readily if the patient's host defense mechanisms are reduced, rendering the patient more susceptible to infection. Therefore, prevention of infection can be accomplished by achieving two goals: first, reducing the number of bacteria in the surgical wound, and second, enhancing host defenses so as to prevent the bacteria that inevitably enter the wound from causing clinically evident infection. Principles of prevention of bacterial invasion of the wound began formulation 100 years before the advent of antibiotics. I Semmelweis in 1850 prevented puerperal fever during childbirth by the introduction of thorough hand washing and the use of chlorine disinfectants. Twenty years later, the Listerin principles of antisepsis in the operating room by the use of carbolic acid sprays had a dramatic effect on the reduction of postoperative infections. By the 1880sthe steam autoclave was introduced by
Koch; the cap and gown were introduced in the 1880s, and the use of sterile rubber gloves was introduced in the 1890s by Halstead.' Thus, by the turn of the century, the principles of antisepsis and asepsis had been firmly established. When these principles were followed, infection rates after clean surgery dropped from more than 90% to less than 15%.1 In contemporary surgery, the most important factor in the prevention of wound infection is adherence to these time-proven principles. Recently it has been suggested that infection rates in clean wounds may be a reliable measure of the surgeon's skill 2 and can be used by quality assurance committees to assess a hospital or individual surgeon's quality of health care delivery. Even when good technique is followed, infection rates following some types of surgery are unacceptably high. In contemporary surgical practice, prophylactic antibiotics are used to reduce this high rate. After the introduction of antibiotics into clinical practice in the late 1940s a major controversy developed regarding the actual efficacy of antibiotics in the prevention of infection. At this time the effectiveness of antibiotics used to prevent infection has been firmly established. Carefully controlled studies in animals and humans by Burke, Polk, and Stone3-5 initially defined these principles. Since their work, more than 200 prospective double-blind studies have continued these principles in essentially every type of surgical endeavor. 6-8 Principles of Antibiotic Prophylaxis
* Professor and Chairman, Oral and Maxillofacial Surgery, College of Dentistry, The Ohio State University, Columbus. Address correspondence and reprint requests to Dr Peterson: Department of Oral and Maxillofacial Surgery, College of Dentistry, The Ohio State University , 305 W 12th Ave, Columbus , OH 43210.
PRINCIPLE I: THE SURGICAL PROCEDURE SHOULD HAVE A SIGNIFICANT RISK OF INFECTION
Surgical procedures have been classified by the expected degree of contamination, and the expected incidence of postoperative infections in each class is known. Class I surgery, also known as clean
© 1990 American Association of Oral and Maxillofacial Surgeons 0278-2391/90/4806-0011$3.00/0
617
618 surgery, occurs when no transection of the respiratory, gastrointestinal (GI), or urinary tracts occurs, and there is no break in surgical-aseptic technique. Clean surgery has an infection rate of approximately 2%. Class II surgery, clean-contaminated surgery, exists when the respiratory, GI, or genitourinary (GU) tract is entered, but when no significant bacterial contamination results. Transoral surgery is considered to be in this class. The expected infection rate in clean-contaminated surgery is 10% to 15%. Class III surgery, contaminated surgery, occurs when there is gross spillage from the GI tract or entry into infected GU or biliary tracts. Fresh traumatic injuries are also considered contaminated surgery. The infection rate in class III surgery is 20% to 30%. Class IV, or dirty surgery, exists when there is established clinical infection, or a traumatic injury more than 8 hours old. It has an infection rate of nearly 50%. By use of good surgical technique, the incidence of infection in class I, or clean surgery cases, can be reduced to less than 1%. In class II surgery, by using excellent technique and prophylactic antibiotics, the incidence of infection can be reduced to approximately 1%; and for class III surgery, to less than 10%.9 Surgical factors other than degree of contamination may also influence infection rates. Operative procedures that last laonger than 3 hours, and procedures for insertion of major foreign bodies (implants), both have increased infection rates. Independent of surgical factors is the issue of host defense status. Even when the degree of contamination may be small, as in clean surgery, patients who have severe host defense compromise may require the use of prophylactic antibiotics. In general, three types of patients have increased susceptibility to infection. The first is the group of patients who have a poorly controlled metabolic disease, including patients who have poorly controlled diabetes, end-stage renal disease, severe alcoholic cirrhosis, and malnutrition syndromes. The second group of patients are those who have diseases that interfere with host defenses, including the myeloproliferative diseases, neutropenia, and agammaglobulinemia. The third group of patients are those taking immunosuppressive drugs that interfere with host defenses, such as cyclosporin and steroids, and cancer chemotherapeutic drugs. When the surgeon feels that the insult of the surgical procedure will result in significant bacterial contamination or that the patient's host defenses are inadequate to resist a bacterial insult of any size, the decision should be made to use prophylactic antibiotics.
ANTIBIOTIC PROPHYLAXIS OF WOUND INFECTION
PRINCIPLE II: SELECT THE CORRECT ANTIBIOTIC FOR THE SURGICAL PROCEDURE
The antibiotic chosen by the surgeon must be effective against the bacteria that are most likely to cause infection following a particular surgical procedure. It is clear that the vast majority of postoperative infections are caused by endogenous bacteria. Thus, the most likely contaminating organisms following transoral oral and maxillofacial surgery are primarily streptococci, anaerobic gram-positive cocci, and anaerobic gram-negative rods. However, it is unlikely that many postoperative infections following transoral procedures are the result of anaerobic bacteria; rather the infections are more likely due to aerobic streptococci. If the surgical procedure is to be done transcutaneously, the most likely organisms that would cause infection are colonizing staphylococci from the skin. The second major factor in selecting the correct antibiotic is use of the least toxic agent available. The toxicity may range from a severe allergic reaction to mild nausea, but all must be considered when selecting an antibiotic. Finally, the antibiotic used should be bactericidal. The goal of the antibiotic is to actually kill bacteria and not just to prevent their reproduction as the bacteriostatic drugs do. Thus, it appears that the choice of prophylactic antibiotic for transoral procedures is penicillin, as it is effective against the bacterial spectrum, nontoxic, and bactericidal. For the patient who has had a nonanaphylactic allergic reaction to penicillin, a first-generation cephalosporin is indicated. For those patients who have had an anaphylactic reaction to penicillin, clindamycin is often recommended as the third choice. For transcutaneous approaches, a first-generation cepahlosporin such as cefazolin is the drug of first choice as it is effective against most staphylococci.
PRINCIPLE
III:
THE ANTIBIOTIC LEVEL MUST BE HIGH
For an antibiotic to be maximally effective, the plasma concentration must be high so as to allow diffusion into the tissues that will be contaminated by the bacteria. To achieve this level, the antibiotic should be given at twice the usual therapeutic dose. Thus, for a drug such as cefazolin whose usual therapeutic dose is 500 mg, the prophylactic dose is two times that or 1 g.
619
LARRY J. PETERSON PRINCIPLE IV: TIME ANTIBIOTIC ADMINISTRATION CORRECTLY
To be maximally effective, the antibiotic should be in the tissue when the bacterial contamination occurs. Practically, this is achieved by administering the antibiotic intravenously a few minutes before the time of surgery. As a general guideline, the antibiotic should not be given the previous day nor in the patient's room before arrival in the operating room. This principle, perhaps more than any other, was the concept that began the rational use of prophylactic antibiotics. Burke? clearly established that the maximum effectiveness of prophylactic antibiotics occurs when the antibiotic is in the tissue when bacteria arrive. He also demonstrated that delaying antibiotic administration for 3 hours after bacterial contamination exerted no more preventive influence than no antibiotic at all. As it is important to maintain high plasma levels of antibiotics in long surgical procedures, the dosage interval must be shorter than the usual therapeutic interval. As a general rule, the dosage interval should be approximately one half of the usual therapeutic interval. For example, for cefazolin, the usual therapeutic interval is 8 hours, and the prophylactic interval is 4 hours. Another way to calculate the interval is to give the drug at two times the plasma half-life. The half-life of cefazolin is approximately 2 hours, which makes the dosage interval 4 hours. PRINCIPLE
V:
USE THE SHORTEST EFFECTIVE ANTIBIOTIC EXPOSURE
It has been well established by Stone et al5 and a large number of other investigators that continuing antibiotic administration after surgery does not decrease the incidence of wound infection. For short procedures, a single dose of antibiotic preoperatively is sufficient to prevent wound infection. For longer procedures, intraoperative doses are given as necessary, and a final dose in the recovery room is sufficient for maximum infection control. This results in a decreased likelihood of toxicity, allergy, and suprainfection, as well as an overall decrease in antibiotic usage and expense. The most important rationale for short-term usage is that additional antibiotic administration does not reduce infection rate. Complications of Prophylactic Antibiotics
The effectiveness of high-dose perioperative antibiotic prophylaxis has been well established.
Equally important is the fact that this type of prophylaxis has been associated with essentially a total absence of side effects and complications. This is not only the result of the fact that antibiotics that have little or no toxicity, such as penicillin and cephalosprins, are used, but also because the short duration of the antibiotic prophylaxis does not provide adequate time for complications to arise. There has been an occasional report or pseudomembranous colitis associated with the prophylactic use of ampicillin, the cephalosporins, and c1indamycin, but this is a relatively rare complication. One of the concerns that is frequently raised is the issue of encouraging the growth of resistant bacteria. However, it appears that selective pressure for overgrowth of resistant bacteria begins only once the host's susceptible organisms are killed, which takes approximately 3 days of antibiotic treatment. Therefore, short-term (l day) prophylactic antibiotic usage has little or no influence on the growth of resistant bacteria. Applications in Oral and Maxillofacial Surgery DENTOALVEOLAR SURGERY
The infection rate following routine exodontia and dentoalveolar surgery is very low. Although hard data are not available, it appears also that the infection rate (excluding alveolar osteitis) for an oral and maxillofacial surgeon removing impacted third molars is less than 1%. Thus, in the normal healthy individual, most dentoalveolar surgical procedures would not require antibiotic prophylaxis to prevent infection. However, if the patient's host defenses are compromised, the surgeon should provide antibiotic prophylaxis for the patient. Patients who are actively receiving chemotherapy for cancer should be treated as patients who are severely compromised, and surgery deferred if possible. If surgery cannot be deferred, then prophylactic antibiotics should be used. Patients who have received organ transplants are on long-term immunosuppressive therapy and also should have their surgery done under preventive antibiotic coverage. In both these settings, the short-term perioperative regimen is sufficient. Patients who have diagnosed metabolic disease that is well controlled do not require antibiotic prophylaxis. For example, the diabetic who has stable disease, who monitors blood sugar on a relatively routine basis, and who is acknowledged to be in good control by both patient and physician, can be treated as a normal patient. However, if the patient
620
ANTIBIOTIC PROPHYLAXIS OF WOUND INFECTION
is the so-called brittle type, with wide fluctuations in glucose levels, and who is acknowledged as being hard to control, prophylactic antibiotic coverage is indicated. TRANSORAL ORTHOGNATHlC, PREPROSTHETlC, AND TUMOR SURGERY
Transoral orthognathic and preprosthetic surgery as well as combined transoral, extraoral approaches for the management of a variety of tumors clearly fall into the class II or clean-contaminated category of surgery. The expected incidence of infection is in the 10% to 15% range. While there is a lack of prospective studies to document the incidence of infection in orthognathic surgery without antibiotics, several reports place it within expected range for class II surgery. 10,11 Other reports place it as high as 25%.12 Because the use of short-term perioperative antibiotics for transoral orthognathic.P craniofacial.!" and tumor surgeryl5,16 has been demonstrated to be effective in preventing postoperative wound infection, it should be used in most situations, MAXILLOFACIAL FRACTURES
It has been a well-established principle of management of compound fractures of the facial skeleton that antibiotics are necessary to prevent infection at the fracture site. 17,18 Approximately 50% of fractures in patients who do not receive antibiotics become infected. The administration of antibiotics reduces this to less than 10%. Recent work in the management of open fractures of the face as well as in open fractures of the extremities has brought attention to the fact that it is highly likely that shortterm antibiotic prophylaxis is equally effective in these situations.I'v'" Administering antibiotics in the perioperative period is all that is required for the prevention of infection in facial fractures. Conclusions
It has become clear that the prevention of infection following surgery can be effectively achieved. A significant portion of this control is due to the skill of the surgeon in applying the basic principles of surgery. However, in some types of surgery, infection rates are unacceptably high. Also, some pa-
tients have compromised defenses and are more likely to have infections after types of surgery where postoperaive infection is usually rare. Maximum reduction of infectious complications can be made in these surgical situations with the appropriate use of peri operative, high-dosage antibiotic administration. The antibiotic must be delivered before the surgical procedure is started, maintained at a high plasma level throughout the period of surgery, and stopped at the completion of the surgical wound closure. The effectiveness of these principles has been well established in the contemporary surgical literature. References I. Alexander JW: The contributions of infection control to a century of surgical progress. Ann Surg 201:423, 1985 2. Joint Commission on Hospital Accreditation: Proposed Clinical Indicators. Chicago, IL, March 1988 3. Burke JF: The effective period of preventive antibiotic action in experimental incisions and dermal lesions. Surgery 50:161, 1961 4. Polk HC, Lopez-Mayor JF: Postoperative wound infection: A prospective study of determinant factors and prevention. Surgery 66:97, 1%9 5. Stone HH, Haney BB, Kolg LD, et al: Prophylactic and preventive antibiotic therapy. Ann Surg 189:691, 1979 6. Kaiser AB: Antimicrobial prophylaxis in surgery. N Engl J Med 315:1129, 1986 7. Antimicrobial prophylaxis in surgery. Med Lett Drugs Ther 29:91, 1987 8. Centers for Disease Control: Guideline for Prevention of Surgical Wound Infections. Atlanta, GA, CDC, 1985 9. Olson M, O'Connor M, Schwartz ML: Surgical wound infections. Ann Surg 199:253, 1984 10. Peterson U, Booth DF: Efficacy of antibiotic prophylaxis in intraoral orthognathic surgery. J Oral Surg 34:1088, 1976 11. Yrastorza JA: Indications for antibiotics in orthognathic surgery. J Oral Surg 34:514, 1976 12. Peterson U: Perioperative prophylactic antibiotics for major oral and maxillofacial surgery. J Dent Res 58:233, 1978 13. Ruggles JE, Hann JR: Antibiotic prophylaxis in intraoral orthognathic surgery. J Oral Maxillofac Surg 42:797, 1984 14. Conover MA, Kaban LB, MuIliken JB: Antibiotic prophylaxis for major maxillofacial surgery. J Oral Maxillofac Surg 43:865, 1985 15. Johnson JT, Schuller DE, Silver F, et al: Antibiotic prophylaxis in high-risk head and neck surgery: One-day vs. fiveday therapy. Otolaryngology 95:554, 1986 16. Fee WE, Glenn M, Handen C, et al: One day vs. two days of prophylactic antibiotics in patients undergoing major head and neck surgery. Laryngoscope 94:612, 1984 17. Zallen RD, Curry JT: A study of antibiotic usage in compound mandibular fractures. J Oral Surg 33:431, 1975 18. Chole RA, Yee J: Antibiotic prophylaxis for facial fractures. Arch Otolaryngol 113:1055, 1987 19. DeIlinger EP, Caplan ES, Weaver LD, et a1: Duration of preventive antibiotic administration for open extremity fractures. Arch Surg 123:333, 1988
E
TH RAPY
J Oral Maxillofac Surg 48 :617-620, 1990
Antibiotic Prophylaxis Against Wound Infections in Oral and Maxillofacial Surgery LARRYJ.PETERSON, DDS· The prevention of wound infection is one of the major goals of every surgeon. When infection does occur, increased patient morbidity and suffering result, with consequent additional expense, increased antibiotic usage, and a delayed recovery. Over the last tOO years, principles of infection prevention have been clearly defined which, when applied, can reduce infection rates to ncar zero. The purpose of this article is to delineate these principles and apply them to the variety of surgical procedures the oral and maxillofacial surgeon is called upon to perform. Infection occurs when there is a significant quantitative and qualitative bacterial insult; it occurs more readily if the patient's host defense mechanisms are reduced, rendering the patient more susceptible to infection. Therefore, prevention of infection can be accomplished by achieving two goals: first, reducing the number of bacteria in the surgical wound, and second, enhancing host defenses so as to prevent the bacteria that inevitably enter the wound from causing clinically evident infection. Principles of prevention of bacterial invasion of the wound began formulation 100 years before the advent of antibiotics. I Semmelweis in 1850 prevented puerperal fever during childbirth by the introduction of thorough hand washing and the use of chlorine disinfectants. Twenty years later, the Listerin principles of antisepsis in the operating room by the use of carbolic acid sprays had a dramatic effect on the reduction of postoperative infections. By the 1880sthe steam autoclave was introduced by
Koch; the cap and gown were introduced in the 1880s, and the use of sterile rubber gloves was introduced in the 1890s by Halstead.' Thus, by the turn of the century, the principles of antisepsis and asepsis had been firmly established. When these principles were followed, infection rates after clean surgery dropped from more than 90% to less than 15%.1 In contemporary surgery, the most important factor in the prevention of wound infection is adherence to these time-proven principles. Recently it has been suggested that infection rates in clean wounds may be a reliable measure of the surgeon's skill 2 and can be used by quality assurance committees to assess a hospital or individual surgeon's quality of health care delivery. Even when good technique is followed, infection rates following some types of surgery are unacceptably high. In contemporary surgical practice, prophylactic antibiotics are used to reduce this high rate. After the introduction of antibiotics into clinical practice in the late 1940s a major controversy developed regarding the actual efficacy of antibiotics in the prevention of infection. At this time the effectiveness of antibiotics used to prevent infection has been firmly established. Carefully controlled studies in animals and humans by Burke, Polk, and Stone3-5 initially defined these principles. Since their work, more than 200 prospective double-blind studies have continued these principles in essentially every type of surgical endeavor. 6-8 Principles of Antibiotic Prophylaxis
* Professor and Chairman, Oral and Maxillofacial Surgery, College of Dentistry, The Ohio State University, Columbus. Address correspondence and reprint requests to Dr Peterson: Department of Oral and Maxillofacial Surgery, College of Dentistry, The Ohio State University , 305 W 12th Ave, Columbus , OH 43210.
PRINCIPLE I: THE SURGICAL PROCEDURE SHOULD HAVE A SIGNIFICANT RISK OF INFECTION
Surgical procedures have been classified by the expected degree of contamination, and the expected incidence of postoperative infections in each class is known. Class I surgery, also known as clean
© 1990 American Association of Oral and Maxillofacial Surgeons 0278-2391/90/4806-0011$3.00/0
617
618 surgery, occurs when no transection of the respiratory, gastrointestinal (GI), or urinary tracts occurs, and there is no break in surgical-aseptic technique. Clean surgery has an infection rate of approximately 2%. Class II surgery, clean-contaminated surgery, exists when the respiratory, GI, or genitourinary (GU) tract is entered, but when no significant bacterial contamination results. Transoral surgery is considered to be in this class. The expected infection rate in clean-contaminated surgery is 10% to 15%. Class III surgery, contaminated surgery, occurs when there is gross spillage from the GI tract or entry into infected GU or biliary tracts. Fresh traumatic injuries are also considered contaminated surgery. The infection rate in class III surgery is 20% to 30%. Class IV, or dirty surgery, exists when there is established clinical infection, or a traumatic injury more than 8 hours old. It has an infection rate of nearly 50%. By use of good surgical technique, the incidence of infection in class I, or clean surgery cases, can be reduced to less than 1%. In class II surgery, by using excellent technique and prophylactic antibiotics, the incidence of infection can be reduced to approximately 1%; and for class III surgery, to less than 10%.9 Surgical factors other than degree of contamination may also influence infection rates. Operative procedures that last laonger than 3 hours, and procedures for insertion of major foreign bodies (implants), both have increased infection rates. Independent of surgical factors is the issue of host defense status. Even when the degree of contamination may be small, as in clean surgery, patients who have severe host defense compromise may require the use of prophylactic antibiotics. In general, three types of patients have increased susceptibility to infection. The first is the group of patients who have a poorly controlled metabolic disease, including patients who have poorly controlled diabetes, end-stage renal disease, severe alcoholic cirrhosis, and malnutrition syndromes. The second group of patients are those who have diseases that interfere with host defenses, including the myeloproliferative diseases, neutropenia, and agammaglobulinemia. The third group of patients are those taking immunosuppressive drugs that interfere with host defenses, such as cyclosporin and steroids, and cancer chemotherapeutic drugs. When the surgeon feels that the insult of the surgical procedure will result in significant bacterial contamination or that the patient's host defenses are inadequate to resist a bacterial insult of any size, the decision should be made to use prophylactic antibiotics.
ANTIBIOTIC PROPHYLAXIS OF WOUND INFECTION
PRINCIPLE II: SELECT THE CORRECT ANTIBIOTIC FOR THE SURGICAL PROCEDURE
The antibiotic chosen by the surgeon must be effective against the bacteria that are most likely to cause infection following a particular surgical procedure. It is clear that the vast majority of postoperative infections are caused by endogenous bacteria. Thus, the most likely contaminating organisms following transoral oral and maxillofacial surgery are primarily streptococci, anaerobic gram-positive cocci, and anaerobic gram-negative rods. However, it is unlikely that many postoperative infections following transoral procedures are the result of anaerobic bacteria; rather the infections are more likely due to aerobic streptococci. If the surgical procedure is to be done transcutaneously, the most likely organisms that would cause infection are colonizing staphylococci from the skin. The second major factor in selecting the correct antibiotic is use of the least toxic agent available. The toxicity may range from a severe allergic reaction to mild nausea, but all must be considered when selecting an antibiotic. Finally, the antibiotic used should be bactericidal. The goal of the antibiotic is to actually kill bacteria and not just to prevent their reproduction as the bacteriostatic drugs do. Thus, it appears that the choice of prophylactic antibiotic for transoral procedures is penicillin, as it is effective against the bacterial spectrum, nontoxic, and bactericidal. For the patient who has had a nonanaphylactic allergic reaction to penicillin, a first-generation cephalosporin is indicated. For those patients who have had an anaphylactic reaction to penicillin, clindamycin is often recommended as the third choice. For transcutaneous approaches, a first-generation cepahlosporin such as cefazolin is the drug of first choice as it is effective against most staphylococci.
PRINCIPLE
III:
THE ANTIBIOTIC LEVEL MUST BE HIGH
For an antibiotic to be maximally effective, the plasma concentration must be high so as to allow diffusion into the tissues that will be contaminated by the bacteria. To achieve this level, the antibiotic should be given at twice the usual therapeutic dose. Thus, for a drug such as cefazolin whose usual therapeutic dose is 500 mg, the prophylactic dose is two times that or 1 g.
619
LARRY J. PETERSON PRINCIPLE IV: TIME ANTIBIOTIC ADMINISTRATION CORRECTLY
To be maximally effective, the antibiotic should be in the tissue when the bacterial contamination occurs. Practically, this is achieved by administering the antibiotic intravenously a few minutes before the time of surgery. As a general guideline, the antibiotic should not be given the previous day nor in the patient's room before arrival in the operating room. This principle, perhaps more than any other, was the concept that began the rational use of prophylactic antibiotics. Burke? clearly established that the maximum effectiveness of prophylactic antibiotics occurs when the antibiotic is in the tissue when bacteria arrive. He also demonstrated that delaying antibiotic administration for 3 hours after bacterial contamination exerted no more preventive influence than no antibiotic at all. As it is important to maintain high plasma levels of antibiotics in long surgical procedures, the dosage interval must be shorter than the usual therapeutic interval. As a general rule, the dosage interval should be approximately one half of the usual therapeutic interval. For example, for cefazolin, the usual therapeutic interval is 8 hours, and the prophylactic interval is 4 hours. Another way to calculate the interval is to give the drug at two times the plasma half-life. The half-life of cefazolin is approximately 2 hours, which makes the dosage interval 4 hours. PRINCIPLE
V:
USE THE SHORTEST EFFECTIVE ANTIBIOTIC EXPOSURE
It has been well established by Stone et al5 and a large number of other investigators that continuing antibiotic administration after surgery does not decrease the incidence of wound infection. For short procedures, a single dose of antibiotic preoperatively is sufficient to prevent wound infection. For longer procedures, intraoperative doses are given as necessary, and a final dose in the recovery room is sufficient for maximum infection control. This results in a decreased likelihood of toxicity, allergy, and suprainfection, as well as an overall decrease in antibiotic usage and expense. The most important rationale for short-term usage is that additional antibiotic administration does not reduce infection rate. Complications of Prophylactic Antibiotics
The effectiveness of high-dose perioperative antibiotic prophylaxis has been well established.
Equally important is the fact that this type of prophylaxis has been associated with essentially a total absence of side effects and complications. This is not only the result of the fact that antibiotics that have little or no toxicity, such as penicillin and cephalosprins, are used, but also because the short duration of the antibiotic prophylaxis does not provide adequate time for complications to arise. There has been an occasional report or pseudomembranous colitis associated with the prophylactic use of ampicillin, the cephalosporins, and c1indamycin, but this is a relatively rare complication. One of the concerns that is frequently raised is the issue of encouraging the growth of resistant bacteria. However, it appears that selective pressure for overgrowth of resistant bacteria begins only once the host's susceptible organisms are killed, which takes approximately 3 days of antibiotic treatment. Therefore, short-term (l day) prophylactic antibiotic usage has little or no influence on the growth of resistant bacteria. Applications in Oral and Maxillofacial Surgery DENTOALVEOLAR SURGERY
The infection rate following routine exodontia and dentoalveolar surgery is very low. Although hard data are not available, it appears also that the infection rate (excluding alveolar osteitis) for an oral and maxillofacial surgeon removing impacted third molars is less than 1%. Thus, in the normal healthy individual, most dentoalveolar surgical procedures would not require antibiotic prophylaxis to prevent infection. However, if the patient's host defenses are compromised, the surgeon should provide antibiotic prophylaxis for the patient. Patients who are actively receiving chemotherapy for cancer should be treated as patients who are severely compromised, and surgery deferred if possible. If surgery cannot be deferred, then prophylactic antibiotics should be used. Patients who have received organ transplants are on long-term immunosuppressive therapy and also should have their surgery done under preventive antibiotic coverage. In both these settings, the short-term perioperative regimen is sufficient. Patients who have diagnosed metabolic disease that is well controlled do not require antibiotic prophylaxis. For example, the diabetic who has stable disease, who monitors blood sugar on a relatively routine basis, and who is acknowledged to be in good control by both patient and physician, can be treated as a normal patient. However, if the patient
620
ANTIBIOTIC PROPHYLAXIS OF WOUND INFECTION
is the so-called brittle type, with wide fluctuations in glucose levels, and who is acknowledged as being hard to control, prophylactic antibiotic coverage is indicated. TRANSORAL ORTHOGNATHlC, PREPROSTHETlC, AND TUMOR SURGERY
Transoral orthognathic and preprosthetic surgery as well as combined transoral, extraoral approaches for the management of a variety of tumors clearly fall into the class II or clean-contaminated category of surgery. The expected incidence of infection is in the 10% to 15% range. While there is a lack of prospective studies to document the incidence of infection in orthognathic surgery without antibiotics, several reports place it within expected range for class II surgery. 10,11 Other reports place it as high as 25%.12 Because the use of short-term perioperative antibiotics for transoral orthognathic.P craniofacial.!" and tumor surgeryl5,16 has been demonstrated to be effective in preventing postoperative wound infection, it should be used in most situations, MAXILLOFACIAL FRACTURES
It has been a well-established principle of management of compound fractures of the facial skeleton that antibiotics are necessary to prevent infection at the fracture site. 17,18 Approximately 50% of fractures in patients who do not receive antibiotics become infected. The administration of antibiotics reduces this to less than 10%. Recent work in the management of open fractures of the face as well as in open fractures of the extremities has brought attention to the fact that it is highly likely that shortterm antibiotic prophylaxis is equally effective in these situations.I'v'" Administering antibiotics in the perioperative period is all that is required for the prevention of infection in facial fractures. Conclusions
It has become clear that the prevention of infection following surgery can be effectively achieved. A significant portion of this control is due to the skill of the surgeon in applying the basic principles of surgery. However, in some types of surgery, infection rates are unacceptably high. Also, some pa-
tients have compromised defenses and are more likely to have infections after types of surgery where postoperaive infection is usually rare. Maximum reduction of infectious complications can be made in these surgical situations with the appropriate use of peri operative, high-dosage antibiotic administration. The antibiotic must be delivered before the surgical procedure is started, maintained at a high plasma level throughout the period of surgery, and stopped at the completion of the surgical wound closure. The effectiveness of these principles has been well established in the contemporary surgical literature. References I. Alexander JW: The contributions of infection control to a century of surgical progress. Ann Surg 201:423, 1985 2. Joint Commission on Hospital Accreditation: Proposed Clinical Indicators. Chicago, IL, March 1988 3. Burke JF: The effective period of preventive antibiotic action in experimental incisions and dermal lesions. Surgery 50:161, 1961 4. Polk HC, Lopez-Mayor JF: Postoperative wound infection: A prospective study of determinant factors and prevention. Surgery 66:97, 1%9 5. Stone HH, Haney BB, Kolg LD, et al: Prophylactic and preventive antibiotic therapy. Ann Surg 189:691, 1979 6. Kaiser AB: Antimicrobial prophylaxis in surgery. N Engl J Med 315:1129, 1986 7. Antimicrobial prophylaxis in surgery. Med Lett Drugs Ther 29:91, 1987 8. Centers for Disease Control: Guideline for Prevention of Surgical Wound Infections. Atlanta, GA, CDC, 1985 9. Olson M, O'Connor M, Schwartz ML: Surgical wound infections. Ann Surg 199:253, 1984 10. Peterson U, Booth DF: Efficacy of antibiotic prophylaxis in intraoral orthognathic surgery. J Oral Surg 34:1088, 1976 11. Yrastorza JA: Indications for antibiotics in orthognathic surgery. J Oral Surg 34:514, 1976 12. Peterson U: Perioperative prophylactic antibiotics for major oral and maxillofacial surgery. J Dent Res 58:233, 1978 13. Ruggles JE, Hann JR: Antibiotic prophylaxis in intraoral orthognathic surgery. J Oral Maxillofac Surg 42:797, 1984 14. Conover MA, Kaban LB, MuIliken JB: Antibiotic prophylaxis for major maxillofacial surgery. J Oral Maxillofac Surg 43:865, 1985 15. Johnson JT, Schuller DE, Silver F, et al: Antibiotic prophylaxis in high-risk head and neck surgery: One-day vs. fiveday therapy. Otolaryngology 95:554, 1986 16. Fee WE, Glenn M, Handen C, et al: One day vs. two days of prophylactic antibiotics in patients undergoing major head and neck surgery. Laryngoscope 94:612, 1984 17. Zallen RD, Curry JT: A study of antibiotic usage in compound mandibular fractures. J Oral Surg 33:431, 1975 18. Chole RA, Yee J: Antibiotic prophylaxis for facial fractures. Arch Otolaryngol 113:1055, 1987 19. DeIlinger EP, Caplan ES, Weaver LD, et a1: Duration of preventive antibiotic administration for open extremity fractures. Arch Surg 123:333, 1988
