Most complications that occur on the day of surgery involve the patient's underlying medical problems, reactions to administered anesthetics, and bleeding. Allergy, hypersensitivity, or toxic reactions to local anesthetics and fainting with or without seizure can also occur.
Patient's Medical Problems
Before surgery, it is important to obtain a medical history and perform a physical examination. The level of physical examination is commensurate with the extensiveness of the surgery that is planned. For example, a small cyst excision would only require a cursory physical exam (i.e., general appearance) and vital signs, whereas an extensive liposuction procedure using a large volume of tumescent anesthesia would require a full physical examination and diagnostic testing, if indicated.
The patient's medical history, including allergies, medications, and past surgeries, is important to obtain. Medications such as anticoagulants, pain medications, and certain herbs can affect bleeding at the time of surgery (Table 247-1).2,3 Excessive bleeding with prior surgeries, especially if requiring transfusions, can be associated with a prolonged bleeding time. It is important to determine if the patient has a cardiac pacemaker, defibrillator, or any other implantable medical devices. Also, if the patient has an artificial heart valve or a rheumatic heart valve, preoperative antibiotics will be required.
Table 247-1 Medications that Inhibit Platelet Function
Some of the common problems associated with skin surgery include fainting, seizures, and diaphoresis. Fainting is almost always a vasovagal reaction, and the best treatment is to position the patient in the Trendelenburg position. Seizures sometimes occur with the vasovagal reaction and are short lived. Usually, when patients faint, there is a history of fainting episodes, pointing out the importance of inquiring about this in the medical history. Diaphoresis may occur associated with a vasovagal reaction, angina, or hypoglycemia.
Certain equipment is necessary to address emergencies. A “crash cart” includes a heart monitor with defibrillator and common medications to manage emergencies. Oxygen tanks with appropriate masks or nasal cannulas should be ready for use and checked regularly. In addition, a blood pressure cuff, heart rate monitor, and pulse oximeter should be available. Although we now live in a “911” culture, the operating physician is still responsible for handling medical problems, and the dermatologic surgeon should be certified in basic or advanced cardiac life support. Furthermore, ancillary staff should be similarly certified and know their role in emergency situations.
Because almost all cutaneous surgery performed by dermatologists is done with local anesthetic, this section only discusses local anesthetic complications. Fortunately, problems with local anesthetics are extremely rare. Thus, physicians have been lulled into a false sense of security. Allergy to lidocaine is rare if it happens at all; generally, the allergy is to the paraben preservative.4
Problems with local anesthetic toxicity are most often related to the total dosage and the addition of epinephrine (see Chapter 242). The total dosage (for a 70-kg patient) should not exceed 500 mg of lidocaine if epinephrine is used and 200 mg if epinephrine is not used.5 Alternative anesthetics such as bupivacaine have a different recommended total dosage. The initial sign of lidocaine toxicity is tongue and circumoral numbness. If this occurs, oxygen should be administered and an intravenous line established.
The addition of epinephrine to local anesthetics is commonplace. However, epinephrine can cause an increase in heart rate, increased contractility of heart muscle, and vasoconstriction. This phenomenon often occurs with inadvertent direct injection into a blood vessel or it could represent a hypersensivity reaction especially if the patient is hyperthyroid. Epinephrine should be given cautiously in patients with severe hypertension or cardiac arrhythmias. In these situations, epinephrine, which is present in prepackaged anesthetic in a dilution of 1:100,000, can be diluted further to 1:200,000 or less without decreasing hemostasis. If patients have a history of sensitivity to epinephrine, it is best to use lidocaine without epinephrine. However, in the absence of epinephrine, the anesthetic duration and level of anesthesia will decrease, and the onset time will increase. Also, the absence of epinephrine in local anesthetic can contribute to increased intraoperative bleeding.
Anesthetic containing epinephrine should not be injected into the digits. Although there is some controversy about this, a patient with unknown diabetes may be at high risk for tissue necrosis. Anesthetic containing epinephrine may be injected into the nose, earlobes, and penis; however, it maybe preferable to do a pudendal nerve block in the latter site.
During and after surgery, a cardinal goal is to minimize blood loss. A medical history helps identify medical problems that might promote bleeding, such as thrombocytopenia, coagulopathy, or hypertension. Several medications inhibit platelet function (see Table 247-1). Anticoagulants should be specifically queried. Extensive intake of garlic, ginkgo, vitamin E, and some other herbs can promote bleeding. During surgery, meticulous hemostasis will help minimize postoperative bleeding.
One medication with specific importance in dermatologic surgery is warfarin (Coumadin). Patients on warfarin should not discontinue this medication before cutaneous surgery. In some patients who stop and start warfarin, the blood becomes hypercoagulable, which may lead to blood clots or strokes.6 Aspirin, on the other hand, is generally safe to stop 10–14 days before surgery, unless the patient has had a history of strokes or transient ischemic attacks.7