Dentoalveolar surgery comprises more than 50% of the practice of oral and maxillofacial surgeons worldwide and is the most commonly performed category of surgical procedure. Optimal strategies for management of many medical problems, however, remain unclear. Remaining current on medical and surgical perioperative strategies is a standard for best practice. This article provides contemporary approaches for the perioperative management of patients presenting for dentoalveolar surgery. Attention will be directed to the perioperative management of cardiovascular disease, diabetes, and obesity. These diseases are chosen owing to controversies with respect to good scientific evidence that supports a standard of perioperative care.
Key points
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As the population ages, dentoalveolar surgical outcomes become more and more reliant on perioperative medical management skills.
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New guidelines exist regarding patients presenting with hypertension in the perioperative period.
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Although there is no consensus statement in oral health, the treatment of patients on anticoagulant and/or antiplatelet therapy require an awareness of evidence-based standards that have been applied in other specialties.
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The perioperative management of diabetes and obesity in surgical patients is complex and controversial owing to a paucity of high-level evidence and expert opinion.
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The perioperative management of cardiovascular disease, diabetes, and obesity continues to be based on high level evidence trials to support a standard of care.
Introduction
Dentoalveolar surgery comprises more than 50% of the practice of oral and maxillofacial surgeons (OMFS) worldwide. Procedures most commonly performed range from simple tooth extractions, implants with or without bony augmentation, preprosthetic surgical removal of tori and exostoses, exposure of impacted teeth for orthodontic treatment, and extraction of impacted third molars. More of the Baby Boomer generation are seeing the OMFS for dentoalveolar surgical intervention. Although many people aged 65 or older remain healthy and visit medical/dental providers either infrequently or for health maintenance care, their cohorts experience increased rates of age-related physiologic changes in the oral cavity, changes owing to the comorbidities of chronic illnesses and changes resulting from medications used to manage diseases.
The optimal strategies for management of many medical problems remain unclear owing to a paucity of high-level evidence and as such, the perioperative management of surgical patients remain in a dynamic state. , A quote of the late poet Emily Dickinson put it best when she said, “If you take care of the small things, the big things take care of themselves.” An appropriate preoperative patient assessment is a critical component of surgical success. ,
Remaining current on medical and surgical perioperative strategies form a continuum for best practice. This article provides contemporary approaches for the perioperative management of patients presenting for dentoalveolar surgery in the OMFS practice. Attention will be directed to the perioperative management of cardiovascular disease, diabetes mellitus, and obesity. These systemic conditions are chosen owing to controversies in the perioperative management strategies with respect to good scientific evidence that supports a standard of care.
Preoperative surgical evaluation
Preoperative evaluation by the OMFS is either performed the day of surgery or several days before. Each surgical patient presents with her or his own unique set of risk factors and comorbidities, and as such, there is no “standard” approach that fits all patients of all ages. A thorough history and physical examination is always required with pertinent findings applicable to the diagnosis, as well as comorbidities that may affect surgical risk. Risk stratification that assesses the fitness of a patient is standard in practice and well characterized by the American Society of Anesthesiologists (ASA; Box 1 ). Preoperative assessment also includes a determination of how well a patient withstands the stress of surgery (as discussed elsewhere in this article; Box 2 ) and heals without any compromise.
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ASA Class 1: Normal Healthy Patient
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No organic, psychiatric, or physiologic disturbance; healthy with good exercise tolerance
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ASA Class 2: Mild Systemic Disease
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No functional limitations; has well-controlled disease of 1 body system; that is, hypertension
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And no systemic manifestations; cigarette smoking, pregnancy, mild obesity
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ASA Class 3: Severe Systemic Disease
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Some functional limitations with controlled disease of 1 or more body organ system or 1 major system with no immediate danger of death; that is, congestive heart failure, stable angina, hypertension that is poorly controlled, morbidly obese and chronic renal failure
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ASA Class 4: Severe Systemic Disease as a Constant Threat to Life
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Has at least 1 severe disease that is poorly controlled or end-stage disease with a risk of death; that is, unstable angina, symptomatic congestive heart failure, chronic obstructive lung disease, hepatic or renal disease
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ASA Class 5: Moribund; not expected to live/survive without an operation
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Not expected to survive more than 24 hours without surgery; imminent risk of death; multiorgan failure, sepsis with hemodynamic instability, coagulopathy that is poorly controlled
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ASA Class 6: Declared Brain Dead; Possible Organ Donor
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“E”: If an E is added to a previously defined ASA that signifies the need for a surgical procedure to be performed emergently
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Category 1
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Minimal risk to patients independent of anesthesia; minimally invasive procedure with little or no blood loss and the operation is done in the office.
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Category 2
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Minimal to moderately invasive procedures; blood loss of less than 500 mL; mild risk to patients independent of anesthesia.
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Category 3:
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Moderately to significantly invasive procedure; blood loss of 500 to 1000 mL with a moderate risk to patients independent of anesthesia.
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Category 4:
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Highly invasive procedure with blood loss of greater than 1500 mL with major risk to patients independent of anesthesia.
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Preoperative laboratory testing can assess risk for perioperative adverse events. Unnecessary testing, however, can lead to possible harm and undue costs. , Evidence-based meta-analyses and systematic reviews have demonstrated a lack of reliable evidence and, as such, the latest guidelines come largely from expert opinion. In 2016 the National Guideline Center/National institute for Health and Care Excellence updated a set of guidelines based on ASA classification for routine preoperative laboratory tests in patients undergoing elective surgery. , A complete blood count is recommended in all patients undergoing high-risk procedures and in ASA class III and IV patients with cardiovascular or renal disease/symptoms. Renal function testing is recommended for ASA class III and IV patients, as well as ASA class II patients with risk for acute kidney injury. Routine coagulation with an international normalized ratio (INR) or platelet count testing should be left to the patient’s cardiologist/primary care provider’s discretion. Coagulation testing is recommended for ASA class III and IV patients undergoing intermediate- or high-risk procedures who also have a history of anticoagulant use and/or liver disease. The guidelines for pregnancy testing includes qualitative beta-HCG for women of reproductive age (for further information, the reader is referred to the references). During the perioperative and postoperative period issues of malnutrition increases the risk of complications and wound healing in the elderly, patients with cancer, and those with immunocompromised disease states. A postoperative catabolic state and subsequent compromise in wound healing will exacerbate underlying systemic diseases. Preoperative laboratory tests for albumin and transferrin can serve as risk predictors for nutritional homeostasis during the perioperative period.
The prospect of surgery provides the OMFS an opportunity to discuss smoking cessation. The issue of smoking and more recently vaping cessation have been under scrutiny in the surgical arena. Tobacco-related disease is the leading cause of preventable death and contributes to $200 billion annually in medical expenses and lost health productivity. , The evidence of a timeline for benefits of smoking cessation can be from 4 to 8 weeks before surgery and evidence supports a decrease in lung hyperactivity, mucociliary clearance, and improved wound healing during this time period. , Other interventions of smoking cessation well tolerated by patients can include first-line medications (varencline, bupropion, and nicotine replacement therapy) unless medically contraindicated. The Affordable Care Act and 2010 Patient Protection Act has expanded the coverage for evidence-based smoking cessation. , , ,
Perioperative management skills are significant in patients who abuse alcohol, cocaine, and other opioids before the perioperative period. According to the 2016 National Survey of Drug Use and Health, 1.8 million people had prescription pain medication use disorder, and 626,000 had a heroin use disorder. In the midst of an epidemic of opioid abuse and overdose-related morbidity and mortality, the use of opioids remains the most common means of providing analgesia in the perioperative period. A thorough history of abuse withdrawal and toxicity screening can lead to cancellation of the procedure even if the drug use did not occur in the acute phase. The preoperative evaluation should identify those with opioid abuse potential to determine whether a further workup is necessary. Screening for high-risk comorbid conditions can help to guide perioperative pain management. Under special circumstances, where emergent surgical intervention is needed, the surgeon will determine whether risk assessment warrants further evaluation; that is, a preoperative urine toxicology screening for methadone, buprenorphine, and fentanyl may be done. Online databases for drug monitoring should also be reviewed for abuse of controlled substance prescribing. (see for further interest and protocols).
Current controversies in the perioperative management of cardiovascular disease, diabetes, and obesity in the dentoalveolar patient are discussed elsewhere in this article.
Perioperative management strategies
Cardiovascular Disease
The oral and maxillofacial surgeon treats a significant number of patients with a history of cardiovascular disease in everyday practice. Cardiac issues remain a significant risk predictor of perioperative morbidity and mortality, and as such may require advanced monitoring throughout the surgical period. The perioperative management focuses on issues of coronary artery disease (CAD), hypertension, congestive heart failure, disturbances of heart rhythm (arrhythmias), and valvular heart disease. In patients with existing or potentially significant cardiovascular problems a physical examination would include an electrocardiogram, blood pressure monitoring in both arms, and auscultation for bruits, thrills, murmurs, and jugular venous distention. Further physical examination requires abdominal percussion and palpation for hepatosplenomegaly and ascites, followed by a peripheral examination of extremities for evidence of pedal edema and clubbing of the fingers. The Goldman Cardiac Risk Index has been the gold standard to assess cardiovascular risk in the noncardiac surgical patient. The index is based on a series of points that, when tallied, can go from 0 signifying a 1.0% cardiac risk to more than 26 points, coinciding with a 63% risk for cardiac death. Additional cardiac risk is stratified according to the American College of Cardiology/American Heart Association 2007 guidelines on perioperative cardiovascular evaluation for noncardiac surgery ( Box 3 ). The Revised Cardiac Risk Index issued to estimates a patient’s risk of perioperative cardiac complications by looking for an association between preoperative variables (eg, patient’s age, type of surgery, comorbid diagnoses, or laboratory data) and the risk for cardiac complications in a cohort of surgical patients (the derivation cohort). Another risk predictor is based on the assessment of a patient’s functional capacity to estimate perioperative risk of cardiovascular complication, and is determined by asking about their physical activity to estimate the metabolic equivalents they can perform without sign of myocardial ischemia. , One metabolic equivalent is the basal oxygen consumption of a 40-year-old, 70-kg man. The physical activity of a patient is quantified by a number of metabolic equivalents and when determined a patient with a MET score of greater than 4 is considered to have good functional capacity and therefore at low risk for a myocardial ischemic event ( Box 4 ). Less than 4 metabolic equivalents require further cardiac risk assessment and may not be a good candidate for ambulatory center surgery. ,
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| Risk for cardiac death, nonfatal myocardial infarction, and nonfatal cardiac arrest: 0 predictors = 0.4%, 1 predictor = 0.9%, 2 predictors = 6.6%, ≥3 predictors = >11% |
| Risk Factor | Points |
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| History of ischemic heart disease | 1 |
| History of congestive heart failure | 1 |
| History of cerebrovascular disease (stroke or transient ischemic attack) | 1 |
| History of diabetes requiring preoperative insulin use | 1 |
| Chronic kidney disease [creatinine >2 mg/dL (176.8 μmol/L)] | 1 |
| Undergoing suprainguinal vascular, intraperitoneal, or intrathoracic surgery | 1 |
| Total points: |
| Risk of Major Cardiac Event | |
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| Total Points | Risk (%) |
| 0 | 0.4% |
| 1 | 0.9% |
| 2 | 6.6% |
| ≥3 | >11% |
The following cardiovascular disease stressors in the dentoalveolar surgical patient are of consideration to the OMFS,
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CAD: Patients at risk for CAD pose significant challenges for perioperative management during surgery, because 5% of patients with CAD who have noncardiac surgery can develop cardiac complications. Perioperative acute events can vary from myocardial ischemia to myocardial injury to myocardial infarction. Undiagnosed heart failure, stroke, diabetes mellitus or renal insufficiency, male sex, and increasing age can all contribute as risk predictors. The administration of sedation can be challenging owing to anesthetic agents masking signs and symptoms of underlying cardiovascular disease. The diagnosis is only confirmed after preoperative laboratory testing is undertaken to determine surgical stressors (discussed elsewhere in this article). Anesthetic management must be tailored toward preventing, monitoring, and detecting any myocardial ischemia, as well as changes in hemodynamic status. Anesthetic medications should be chosen based on a favorable hemodynamic profile. Hemodynamic goals include maintaining a normal heart rate, normal to high blood pressures, and avoiding fluid overload that can increase myocardial demand and decrease oxygen perfusion. If patients do complain about symptoms, all nonemergency surgical procedures are postponed and the patient is transported to the hospital emergency room for a cardiac workup. ,
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2.Hypertension: Hypertension is commonly seen in at least one-third of noncardiac patients scheduled for elective surgery. The 2017 guidelines for hypertensive patients suggest that 50% of the population may be considered hypertensive and that early treatment can avoid morbidity and possible mortality from CVD. The staging has the following category, systolic and diastolic numbers: <120/<80; normal; 120 to 129/<80; prehypertensive; 130 to 139/80 to 89; Stage 1 and >or = 140/> or = 90, Stage 2. The stage II hypertensive patient with a diastolic BP <110, for instance, may qualify as a candidate for elective surgery if he/she has no other comorbid conditions. Perioperatively, severe hypertension; that is, >210/110 mm, however, can have a severe hypotensive response under anesthesia and as such, office surgery should be deferred pending further medical work up. A BP of > 180/110 mm with other comorbidities should also be evaluated to prevent adverse cardiac events. , Preoperative administration of anti-hypertensive medication can be continued during the perioperative period, however, Renin-Angiotensin (ACE) inhibitors can cause intraoperative hypotension and may be held before surgery based upon the patient’s need. There is, however, controversy and evidence-based data is still under scrutiny for the perioperative use of ACE inhibitors. Patients on Beta-blockers are advised to continue them perioperatively to avoid withdrawal symptoms. , , The relative risks and benefits of antihypertensive use during surgery can be decided on a case to case basis with a reasonable goal to maintain a patient’s blood pressure within 20% of their respective baseline. , , ,
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Heart failure: Heart failure is a syndrome of impaired cardiac function often associated with either systolic failure or diastolic failure based on diminished ejection fractions during cardiac output. This condition can result in perioperative adverse events in up to 10% of patients during the perioperative period of noncardiac surgery. Heart failure can be right sided or left sided. Left-sided symptoms include orthopnea, pedal edema, tachypnea, and crackles on auscultation of lung fields. Right sided heart failure symptomatology includes pedal edema, nausea, vomiting, and hepatic congestion. Left-sided heart failure is often the most common cause of right-sided heart failure. Perioperative management begins with a thorough workup that consists of an electrocardiogram, chest radiograph, and biomarker analysis using brain natriuretic peptide, which has a high specificity for ruling in heart failure. Additional testing include electrolytes, renal and liver function tests, and an echocardiogram to determine new or chronic wall motion irregularities of the heart. , Pharmacologic therapy can include angiotensin-converting enzyme inhibitor and beta blocker therapy as per American College of Cardiology/American Heart Association guidelines (see , for further interest).
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Symptomatic arrhythmias: Many of the patients who present to the OMFS practice are being treated with anticoagulant or antiplatelet therapy as a result of arrhythmias associated with atrial fibrillation; that is, the lack of coordinated electrical contraction of the atria. The OMFS must monitor the patient during surgical intervention because a multitude of factors can precipitate atrial fibrillation; that is, fluid shifts, electrolyte imbalances, and catecholamine release either by the stress of surgery or administration of local anesthetics. Perioperatively, these hemodynamic consequences of atrial fibrillation are of particular concern with respect to decrease in cardiac output, ventricular filling, and the formation of clots in the left atrium that predisposes the risk of a stroke.
Treatments for cardiovascular diseases such as heart valve replacement, atrial fibrillation, and venous thromboembolism have become more common and millions of patients receive anticoagulant and antiplatelet therapies to decrease thrombosis and life-threatening sequela; that is, ischemic events in the heart, lungs, and brain. , , The medical and dental communities have sought to craft a wide variety of strategies during the perioperative period to modify anticoagulant and antiplatelet therapy and prevent an acquired bleeding dyscrasia during and after dental surgery (discussed elsewhere in this article). Other common antiarrhythmic drugs administered during the perioperative period are calcium channel blockers, beta-blockers, and digoxin (for further treatment of atrial fibrillation arrhythmias, the reader is referred to ).
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Perioperative management of acquired bleeding dyscrasias: Perioperative medical therapy can address a significant number of patients who receive either oral anticoagulants or antiplatelet therapies as the most effective prophylactic medications to reduce thrombotic sequelae. These therapies, however, can predispose them to acquired bleeding disorders that can be life threatening. The general algorithm for managing patients on either direct or indirect anticoagulants or antiplatelet medications is to first characterize the potential for severity of bleeding based on the procedure that is planned and whether or not it will pose a significant risk. Routine dental procedures such as localized periodontal scaling or single tooth extraction may be considered low risk and as such do not require a change in anticoagulating doses. As the complexity of the procedure increases and surgical time increases, so does the potential for hemorrhage. For elective surgery, one might consider staging procedures to decrease risk for a hemorrhagic event (ie, limiting the number of extractions per visit, conservative flap design, etc).
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Anticoagulants: Several studies have suggested that often anticoagulation can continue without interruption. High-risk procedures, however, lack a consensus statement with respect to continuation of therapy. Van Diermen and colleagues recommend discussion with the patient’s physician if the INR is greater than 3.5 and complicated oral surgery is planned. Other studies did not confirm the association of increased risk of bleeding and a high INR. Bajkin and colleagues studied 54 patients with INR values between 3.5 and 4.2 who had up to 3 teeth extracted and recorded postoperative bleeding at 3.7% (2/54). Scully and Wolff found that uncomplicated extraction of 3 teeth was safe if the INR is less than 3.5, whereas Chugani suggested that periodontal flaps, implant placement, and apicoectomy were not recommended in patients with INR ranges of 3.0 to 4.0. Several studies mentioned that, along with INR values and surgical trauma, an important risk predictor that is associated with a greater chance of significant bleeding is inflammation of the dental tissue environment. , Ward and Smith reviewed the literature in comparison with current practice by OMFS who perform dentoalveolar procedures for the anticoagulated patient. They concluded that for moderate- to high-risk procedures warfarin discontinuation is recommended to minimal therapeutic levels as determined by the INR (as discussed elsewhere in this article). , Future prospective trials are required, however, for stronger management guidelines in this population of patients.
Newer oral anticoagulants have been developed as alternatives to warfarin. Among these are Xa inhibitors, rivaroxaban (Xarelto) and apixaban (Eliquis), as well as dabigatran (Pradaxa), a direct thrombin inhibitor. Because there are no specific tests to monitor the effects of these medications, good patient compliance is essential. For patients taking these medications, there are increased risks of life-threatening bleeding in severe trauma or nonelective major surgery because there are currently no antidotes available except for dabigatran (Praxbind: Idarucizvmab). The decision to preoperatively discontinue these medications should be based the risks of bleeding associated with the proposed procedure and in consultation with the patient’s physician. In simple surgical procedures such as a single tooth extraction using local hemostatic measures, there is usually no need to discontinue these newer mediations preoperatively. In general, the risk of thromboembolism increases transiently as anticoagulants are discontinued, so careful planning of elective procedures will benefit the patient. In more complex procedures such as multiple dental extractions or more major maxillofacial surgery, anticoagulant or antiplatelet medications may need to be stopped for several days in coordination with the patient’s physician.
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Antiplatelet drugs: Surgeons are faced with the same dilemma of whether or not to discontinue antiplatelet therapy during perioperative dental and oral and maxillofacial surgical intervention because this period is associated with an increased risk of a thrombotic and/or hemorrhagic event. The latter is predicated on the timing of pharmacologic therapy; that is, when the angioplasty or stenting took place. Rebound platelet activity has the potential for a severe thrombotic event. , Patients who are on combination medicine regimens require special consideration. The most common combinations consist of antiplatelet agents and nonsteroidal anti-inflammatory drugs, as well as herbal supplements such as garlic, ginseng, fish oil, and Ginkgo. Aspirin and nonsteroidal anti-inflammatory drugs may be discontinued at the discretion of the practitioner. For most outpatient procedures, the continuation of the antiplatelet therapy outweighs risk of discontinuation. It is prudent, however, to consult with the patient’s cardiologist and cardiac surgeon, because their expertise is as rigorous as ours with respect to Level A evidence (see Table 1 for full list of anticoagulants and antiplatelet medications, as well as references for further interest).
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