Prophylactic Antibiotics for Head and Neck Surgery

Head and neck surgeries that involve the mucous membrane are particularly prone to infection, so doctors administer a strong dose of antibiotics before the procedure to head off potential infection.

Prophylactic antibiotics are medications administered before most surgeries to prevent infection at the surgical site. The antibiotics protect the surgical wound from contamination by microorganisms present in the environment as well as the patient’s own body.

Prophylactic antibiotics are usually given as a single intravenous dose within an hour before the procedure for surgeries that take less than four hours. Longer surgeries may require additional antibiotic doses. Prophylactic antibiotics are generally discontinued within 24 hours after completion of surgery.

Human body is colonized by trillions of bacteria, many of which are beneficial to human health, provided they are confined to the spaces they inhabit. Human saliva contains over 100 types of bacteria per milliliter. The mucous tissue (mucosa) that line the mouth, nose, digestive, bronchial and urogenital tracts have great concentrations of microbes.

Wound infections are one of the most common complications from surgeries. Head and neck surgeries have a particularly high potential for microbial infection because many of them involve surgical incision in the mucosa of the mouth or throat.

The use of prophylactic antibiotics greatly reduces the incidence of post-surgical infections and the related risks. Prevention of infection hastens recovery and reduces the duration of hospital stay, leading to overall reduction of treatment costs.

Selection of the appropriate antibiotic is based on various factors such as:

• The bacteria that is most likely to cause infection. If only a skin incision is made, a prophylactic effective against commonly found skin bacteria (skin flora) is used. If mucosal incision is involved, an antibiotic that is effective against both skin and mucosal flora is chosen.
• Chemical properties and toxicity of the drug.
• If different antibiotics are equally useful for prophylaxis, the least likely antibiotic that may be required for serious infections is chosen. This helps in preventing development of antibiotic resistance.
• Antibiotic sensitivities specific to the particular hospital’s environment. Some hospitals may have high incidence of methicillin-resistant infections while infections resistant to vancomycin or clindamycin may be more common in other hospitals.

Antibiotics commonly used for prophylaxis include the following:

Penicillin

Side effects include:

• Hypersensitivity reactions
• Kidney damage
• Low potassium (hypokalemia)
• Cephalosporin
• Side effects include
• Hypersensitivity reactions

Reduction in levels of blood cells such as:

• Neutrophils (neutropenia)
• Leukocytes (leukopenia)
• Platelets (thrombocytopenia)
• Gastrointestinal problems such as
• Nausea and vomiting
• Diarrhea
• Anorexia
• Kidney damage

Erythromycin

Side effects include:

• Hypersensitivity
• Gastrointestinal problems
• Liver injury (cholestatic hepatitis)

Clindamycin

Side effects include:

• Hypersensitivity
• Mild nausea and diarrhea
• Leukopenia
• Clostridium difficile colitis
• Liver toxicity (rare)

Metronidazole (Flagyl)

Side effects include:

• Central nervous system toxicity
• Gastrointestinal problems
• Neutropenia
• Drug fever
• Delay in blood clotting
• Reactions with alcohol

All neck and head surgeries do not need prophylactic antibiotics. Certain superficial surgical procedures, in which the skin is prepared for surgery and there is no mucosal tissue involvement, usually do not need prophylactic antibiotics.

Surgical wounds are classified as follows:

• Clean wound: Uninfected operative wound from incision made under sterile conditions, with no mucosal tissue involvement.
• Clean-contaminated: Uninfected surgical wound from sterile operative conditions, involving mucosal tissue.
• Contaminated: Open, fresh accidental wounds with skin break and mucosal involvement, but without an infection.
• Dirty-infected: Infected wounds with or without mucosal involvement, present before the operation.

Antibiotic prophylaxis is administered for all the above types of surgical wounds, except clean wounds, in otherwise healthy people. High-risk patients who are immune compromised may require prophylactic antibiotics for all surgical procedures including clean wounds.

High risk factors include the following:

• Cancer at advanced stages
• Human immunodeficiency virus (HIV) infection
• Smoking
• Co-existing conditions (comorbidities)
• Major reconstruction of surgical wound
• Tracheostomy procedure
• Malnourished patient

Following are some of the head and neck surgeries that require prophylactic antibiotic regimens:

• Noncontaminated head and neck surgery: Antibiotic prophylaxis is used only to protect against gram-positive skin flora, in procedures such as:
  • Neck dissection
  • Removal of parotid gland (parotidectomy)
  • Removal of thyroid gland (thyroidectomy)
• Contaminated head and neck surgery: Antibiotic prophylaxis effective against skin and oral flora, which include aerobic and anaerobic bacteria, is used in procedures such as:
  • Composite resection: Removal of part of the lining of the mouth and lower jaw, to treat cancer.
  • Glossectomy: Removal of a part or whole of the tongue due to cancer.
  • Maxillectomy: Removal of part of the upper jaw to treat cancer.
• Nasal and sinus surgery: Nasal area is contaminated with bacteria and prophylactic antibiotics are essential for nasal and sinus surgeries.
• Facial fractures: Antibiotic prophylaxis is essential for open facial fractures.

The disadvantages of antibiotic prophylaxis include:

• Treatment becomes more expensive
• Antibiotic resistance and superinfection
• Allergic and toxic reactions
• Antibiotic side effects
• Increased hospital stays
• Infection with bacteria such as Clostridium difficile, due to side effects, particularly with clindamycin