Smoking impairs tissue oxygenation, which delays healing and increases risk of infection. Smoking cessation should be strongly encouraged at every preoperative consultation. Recommend nicotine replacement therapy even for patients who aren’t willing to quit altogether; point out that giving up cigarettes for just 30 days (or more) before surgery can decrease the likelihood of complications.28
In addition to these identified risk factors, anything that compromises the immune status increases the risk of infection. Alcohol or drug abusers, chronic pain patients, transplant recipients, cancer patients taking immunosuppressants, postsplenectomy patients, and patients with HIV are all at increased risk. Identify any such conditions during your preoperative evaluation, and be sure to include them in your communication with the surgical team.
A common request in preop consults relates to bacterial endocarditis prophylaxis. Only an extremely small number of cases of infective endocarditis occur with dental procedures, however, so the benefits of antibiotic prophylaxis would be minimal, even if the prophylactic therapy were 100% effective.32 As a result, the ACC/AHA guidelines recommend prophylaxis for dental procedures only for patients with underlying cardiac conditions associated with the highest risk of adverse outcome from infective endocarditis. Administration of antibiotics solely to prevent endocarditis is not recommended for patients undergoing genitourinary or gastrointestinal tract procedures.32
Hematologic evaluation: Address risks of bleeding, clotting
Historically, a variety of tests have been employed in an effort to identify patients at risk for bleeding complications prior to surgery—including prothrombin time, partial thromboplastin time, platelet count, and bleeding time, or platelet function. While highly reproducible, automated, and inexpensive when considered individually, the cumulative cost of routine use of these tests is high.33
A recent review of the literature indicates that, for surgical patients without synthetic liver dysfunction or a history of oral anticoagulant use, routine testing is of little value in the assessment of bleeding risk.34 Patients with a negative bleeding history do not require routine coagulation screening prior to surgery.35
Instead, use the medical history to identify risk factors for bleeding. These include excessive bruising, nosebleeds, prolonged bleeding after cuts, bleeding >3 minutes after brushing teeth, and heavy or prolonged menses (TABLE 1). Patients with a past medical history of liver disease; renal failure; hypersplenism; hematologic disease; collagen vascular disease; hemophilia or other inherited hemorrhagic disorder; gastrointestinal or urogenital blood loss; and severe bleeding after dental extraction, other surgery, or childbirth are also at heightened risk, as are those who take medications that affect hemostasis. Physical findings suggestive of risk include purpura, hematoma, jaundice, and signs of cirrhosis.34
While laboratory testing is only appropriate to confirm those at risk in the subpopulation selected by the history and physical, here, as with other adjunctive testing, it is important to consider local standards and the preferences of the surgeon who requested the preop consult.
Treat anemia. Preoperative anemia is linked to adverse outcomes in surgical patients,36 although it is not clear whether the anemia itself or the perioperative transfusions associated with the condition are at the root of the problem.37 Macrocytic anemia may require treatment with vitamin B12 and folate; iron deficiency anemia is treated with iron. Some physicians also recommend the use of erythropoietin starting 3 weeks prior to surgery for patients with normocytic anemia with hemoglobin <13 g/dL.38,39
Thromboembolism risk. Excessive clotting is responsible for more perioperative complications than excessive bleeding. There is a high prevalence of venous thromboembolism (VTE) among surgical patients, with both patient- and procedure-specific risk factors. Although a variety of coagulopathies increase the baseline risk for VTE, routine laboratory screening of the general surgical population for thrombophilia is not recommended.34,35
When risk factors are present based on both the patient’s medical history and the type of procedure, prophylactic measures may be needed (TABLE 3). Options include mechanical prophylaxis (graduated compression stockings and intermittent pneumatic devices) and chemoprophylaxis. Recommended for high-risk cases, such as patients undergoing orthopedic surgery that precludes early mobilization, chemoprophylaxis options include low-molecular-weight heparin, low-dose unfractionated heparin, fondaparinux (a synthetic factor Xa inhibitor), and vitamin K antagonists such as warfarin.40 Aspirin alone is not recommended, as it has not been found to be an effective prophylaxis for VTE.
CASE After following this system-by-system review of your patient, Charlie H, you identify and explicitly communicate the following risk factors in your consultation note:
- Cardiovascular: type 2 diabetes, low functional capacity
- Pulmonary: advanced age
- Renal: advanced age
- Infectious: type 2 diabetes, advanced age, BMI=39
- Hematologic: advanced age, obesity
Based on these findings, you develop the following plan for Charlie H, detailed in the consultation note you submit to the surgical team: