You’ve spent hours preparing your patient for surgery—explaining the procedure, getting the informed consent, verifying insurance, and making sure that postoperative help is available. But then you get the medical clearance report with a “delay surgery” recommendation. It’s frustrating for both you and your patient.
You don’t have to wait until the last minute to identify potential medical clearance problems. The following five steps (Table 1) can help you assess surgical readiness early and take action to prevent delays or cancellations.
Predicting electrolyte abnormalities
Electrolyte disturbances can frequently be predicted by looking at a patient’s medication list. For this reason and because identifying asymptomatic renal impairment in this setting is rare, many guidelines do not recommend routine screening with a renal function panel (RFP) or basic metabolic panel (BMP). However, these laboratory screens can enable a surgeon to identify any electrolyte disturbances and correct them before they become concerns in the immediate preoperative period.
Additionally, renal insufficiency does increase a patient’s risk for postoperative pulmonary complications and mortality, two key factors in risk stratification. Assessing these lab values will enable the anesthesiologist and pharmacists to adjust medication doses if an underlying renal impairment exists.
Using a complete blood count (CBC) to determine a surgically significant anemia in an asymptomatic patient occurs in less than 1 percent of cases. However, anemia is a common postoperative complication that is difficult to assess without a preoperative baseline. Moreover, preoperative hemoglobin and hematocrit values are predictors of postoperative mortality.
Although the data aren’t conclusive, mortality risk associated with anemia may be modifiable by correcting the preoperative anemia. A CBC also provides a platelet count, which can be helpful if a regional anesthesia or nerve block is used.
Controlling blood pressure
Despite the recently released relaxed blood pressure goals, about one-third of American adults have hypertension. But the other extreme, hypotension, can also be cause for delaying a surgical procedure. It is essential to know how to manage a patient’s home medications to mitigate this risk.
Certain blood pressure medicines, including beta blockers, can provide cardiac benefit and should be continued even on the day of surgery, while others, such as diuretics, can make optimization of fluid status difficult, and generally should not be taken on the day of surgery. If a patient’s blood pressure appears to be poorly controlled preoperatively, an assessment by an internist may help to optimize the patient and ensure operating room readiness.
Managing respiratory conditions
Pulmonary disease is more common in the elderly, but it is important to understand every patient’s baseline respiratory status prior to surgery. The most common and validated method for doing so is by gauging the individual’s ability to expend energy before becoming short of breath.
Metabolic energy equivalents (METs) are used to quantify the energy used doing daily activities (Table 2). Multiple studies recommend that 4 METs—equivalent to doing light housework, climbing a flight of stairs, or walking on ground level at 4 miles per hour without becoming short of breath—are required to safely undergo a surgical procedure with minimal pulmonary risk.
The American College of Physicians also recommends a screening radiograph for patients with known cardiopulmonary disease. When combined with a physical exam, a radiograph can often help to clinically determine if further interventions are necessary prior to surgery.
Detecting active cardiac conditions
All orthopaedic procedures are considered intermediate risk for cardiac complications, meaning the reported cardiac risk is 1 percent to 5 percent. Thus, an EKG is recommended for all patients with known cardiac diseases, such as coronary artery disease, arrhythmias, peripheral arterial disease, cerebrovascular disease, and structural or valvular heart disease.
The American College of Cardiology and the American Heart Association have developed several risk stratification tables and guidelines that can aid in determining operating room readiness in a patient with known or suspected cardiac disease. However, the most common reason a surgical procedure will be delayed is due to active cardiac conditions: acute myocardial infarction in the last 30 days, decompensated heart failure, severe valvular disease, or unstable arrhythmia. These conditions can often be detected by a thorough history and physical examination and require urgent evaluation by a cardiologist prior to the patient’s undergoing an orthopaedic procedure.
The goal of preoperative screening is to ensure a patient’s safety for undergoing a surgical procedure. Often, a surgeon can do this without the counsel of an internist. However, if you have any concerns, it’s wise to consult a general internist and/or cardiologist preoperatively to help identify and minimize any previously unrecognized risks, while maximizing current treatment for any known risk. Their goal is the same as yours: to get the patient to the operating room in an efficient and safe manner.
Jordyn Griffin, MD, is a PGY-3 resident in internal medicine/pediatrics at the University of Kentucky; he can be reached at Jordyn.email@example.com
Learn More about Medical Clearance Issues
Even if orthopaedic surgeons obtain medical clearance on patients prior to elective surgery, issues such as smoking, obesity, or osteoporosis can have a significant impact on outcomes. “Is Medical Clearance Enough? Understanding Issues that Can Affect Your Patients’ Outcomes,” Instructional Course Lecture (ICL 104), will discuss the many systemic, endocrine, and nutritional issues that can affect outcomes for orthopaedic patients but are not necessarily addressed simply by obtaining medical clearance. ICL 104 will take place during the 2015 AAOS Annual Meeting on Tuesday, March 24, at 8:00 a.m.