OVERVIEW OF OPERATIVE THERAPY FOR OLDER PERSONS
PREOPERATIVE ASSESSMENT AND MANAGEMENT
POSTOPERATIVE MANAGEMENT OF SELECTED MEDICAL PROBLEMS
Surgery is a common form of treatment for older persons; currently more than 55% of all operative procedures are done in patients aged 65 or over, and the proportion is expected to grow. Many of the chronic conditions that increase in prevalence with advancing age—cataracts, arthritis, vascular occlusions, and cancers—are amenable to surgery. Over half of all malignancies occur in patients aged 65 or over, and the primary treatment for many tumors is surgical. Advances in surgical, anesthetic, and medical care have lowered surgical risks and shifted the risk-benefit ratio to favor surgery in increasingly older patients with more complex conditions. Nevertheless, although older patients account for just over half of all surgical procedures, they suffer three quarters of the postoperative mortality and also the disproportionate majority of postoperative morbidity as well. For this reason, physicians are commonly asked to perform preoperative evaluations to reduce the risks of complications and death and to optimize patient outcomes.
Many of the changes of normal aging physiology impact the perioperative management of the elderly surgical patient. For example, altered body composition, diminished kidney function, and decreased liver blood flow and enzyme activity all contribute to changes in the pharmacokinetics of drugs. Cardiac and vascular stiffening complicate fluid management and optimization of intravascular volume. Both volume overload and volume depletion occur commonly and are poorly tolerated by many older persons. Stiffening of the thoracic cage and decrements in ciliary function contribute to decreases in pulmonary reserve and heightened risk of postoperative pneumonia. Because of decreased thermoregulation, the older surgical patient is at particular risk for perioperative hypothermia. Finally, by mechanisms that are not yet fully elucidated, changes in the brain that accompany aging make older individuals exquisitely susceptible to postoperative cognitive changes. The cumulative effect of multiple organ systems with limited physiologic reserve results in “homeostenosis,” a condition that greatly increases the risk of iatrogenic events. (See Biology, especially.)
It is well recognized that the aging process is extremely variable from person to person and that within a person not all organ systems age at the same rate, producing dramatic heterogeneity even among healthy elderly persons. Older individuals may have accumulated several chronic conditions that may impact on the perioperative care, either directly or through the medications they use to treat those conditions. The heterogeneity in physiologic aging combined with the potential for multiple accumulated comorbidities means older patients require a more complex and individualized preoperative evaluation. They often benefit from a multidisciplinary approach to perioperative care and recovery.
It is estimated that 25% to 30% of postoperative deaths are from cardiac causes, and the rate of postoperative cardiac events is directly related to age. Cardiac risk assessment is the most fully developed and widely investigated portion of the preoperative medical assessment. Several schemes are available to help calculate cardiac risk, and decision trees have been well described to guide risk assessment and management. The American Society of Anesthesiologists (ASA) classification of patient physical status relies heavily on clinical judgment and is not specific for cardiovascular morbidity and mortality (see Table 14.1). This system has been used by anesthesiologists for years and has consistently been shown to be useful in predicting postoperative outcomes. An early cardiac risk index by Goldman and colleagues was published in the 1970s, a time when surgery on frail 80- and 90-year-olds was uncommon. The American College of Cardiology and the American Heart Association (ACC/AHA) Guideline for Perioperative Cardiovascular Evaluation for Noncardiac Surgery is widely employed to help stratify risk and direct management. This algorithm takes into account clinical predictors, functional status, and surgical risk and is available on the web at http://www.acc.org/clinical/guidelines/perio/update/periupdate_index.htm.
Because of increasing recognition of the benefit of medical therapy to reduce preoperative cardiac events in patients with clinical risk factors and mounting evidence of little benefit of noninvasive stress testing and invasive therapies to reduce preoperative cardiac events, the trend is now moving away from special preoperative cardiac testing and more toward treating with medical therapies on the basis of clinical judgment. A coronary artery revascularization prophylaxis study demonstrated in a prospective and randomized controlled trial that in patients undergoing elective repair of abdominal aneurysm or surgical therapy for peripheral arterial disease who have coronary artery disease (CAD) amenable to revascularization, revascularization either by coronary artery bypass grafting (CABG) or angioplasty resulted in a delay until a proposed vascular surgery but otherwise no difference in postoperative death, myocardial infarction, stroke, dialysis, loss of limb, or survival up to 2.6 years in comparison with medical therapies, even in high-risk groups. It should be noted that patients with indications that have been shown to clearly benefit from CABG (ie, known left main disease, unstable angina, and multivessel disease with low ejection fraction) were excluded from randomization. Also, risk of perioperative myocardial infarction is markedly elevated when the surgical procedure is performed within the first 6 weeks after angioplasty and stenting. It seems clear that revascularization should not be performed simply to “get someone through a surgical procedure” and that this approach may be in fact harmful. The preoperative cardiac evaluation is therefore is quite simplified in the geriatric age group (see Figure 14.1).
The evidence base supporting the use of perioperative β-blockers, particularly in patients aged 65 or over with known CAD or risk factors for CAD, appears well established. This means the majority geriatric patients undergoing surgery are likely to derive benefit from perioperative β-blocker usage unless there is a clear contraindication to this. Growing interest in the use of both aspirin and so-called statin medications (HMG CoA reductase inhibitors) is based on evidence of benefit of these therapies from nonrandomized studies in high-risk patients. In a prospective but nonrandomized study of over 5000 patients undergoing CABG, those patients taking aspirin within 48 hours of their surgery had nearly a 50% reduced risk of myocardial infarction and stroke, almost three quarters the rate of kidney failure, and no increase in the risk of bleeding or gastritis. A case-control study of patients undergoing elective peripheral vascular surgery found that current users of statin medications had an 80% reduction in the odds of postoperative death in comparison with nonusers. Randomized trials of both of these therapies are needed to further investigate their utility in reducing postoperative cardiac complications.
The greatest risks associated with valvular heart disease include heart failure and endocarditis. Prophylactic antibiotics are recommended to prevent bacterial endocarditis in selected patients undergoing specific procedures. The highest risk for endocarditis is among patients with prosthetic cardiac valves, complex congenital heart disease, and surgically constructed systemic-pulmonary shunts or conduits, or a previous history of endocarditis. Patients at moderate risk are those with other congenital cardiac malformations, acquired valvular dysfunction, hypertrophic cardiomyopathy, and mitral valve prolapse with regurgitation or thickened leaflets, or both. Endocarditis prophylaxis is recommended for patients undergoing procedures that involve the respiratory, biliary or intestinal mucosa, prostate surgery, cystoscopy, or urethral dilation. For the most recent guidelines of the American Heart Association, see their Web site: http://www.amhrt.org.
Postoperative pulmonary complications have been reported to prolong the hospital stay by an average of 1 to 2 weeks in the elderly age group. The in-hospital mortality rate for those with postoperative respiratory failure is around 40%, versus 5% for those without respiratory failure. Possible patient-related factors for development of pulmonary complications postoperatively include smoking, general health status, age, obesity, chronic obstructive pulmonary disease (COPD), neurologic status, cardiovascular status, and intravascular volume shifts. Procedure-related risk factors include the site of the incision, length of the surgery, and type of anesthesia. The risk of pulmonary complications increases as the incision approaches the diaphragm; upper abdominal and thoracic procedures carry the greatest risk (10% to 40%).
A recent investigation of over 160,000 veterans undergoing noncardiac surgery established a clinical prediction model for postoperative pneumonia. Patients were assigned points based on the type of operation, age decile, functional status, and selected clinical conditions (weight loss, administration of general anesthesia, impaired sensorium, history of stroke, level of blood urea nitrogen, and transfusion of greater than 4 units of blood). Individual points were summed to create a score, and the study sample could be divided into five risk classes according to these scores. Pneumonia rates were 0.2% among those with 0 to 15 risk points, 1.2% for those with 16 to 25 risk points, 4.0% for those with 26 to 40 risk points, 9.4% for those with 41 to 55 risk points, and 15.3% for those with more than 55 risk points. As an example, an 82-year-old woman (17 points) with some functional limitations (6 points) who was undergoing an open cholecystectomy (10 points) under general anesthesia (4 points) would have a score of 37 points and fall into the category of those patients with 9.4% risk of postoperative pneumonia. This tool may be useful in guiding perioperative respiratory care, including encouragement of coughing, deep breathing exercises, incentive spirometry, and early mobility to reduce the risk of respiratory problems.
Whether age independently increases the risk of postoperative pulmonary complications is not clear. Chronologic age is less predictive of pulmonary complications following surgery than the presence of coexisting conditions. Patients with COPD have a threefold higher risk of postoperative pulmonary complications. Even among those with severe COPD, age has not been shown to be an independent risk factor for pulmonary complications. The use of perioperative pulmonary function tests in patients with known lung disease is largely discouraged but may be useful in evaluating dyspnea or wheezing when the diagnosis is unknown.
Thromboembolic complications, including pulmonary embolism, are common during the perioperative period. Since these complications can be serious and difficult to treat, attention is focused on prophylaxis. The most commonly used prophylactic regimens for patients over age 60 who are having general surgery are low-dose unfractionated heparin or low-molecular-weight heparin administered subcutaneously. More details regarding prophylactic anticoagulant regimens are found in the Appendix.
When a patient who is being treated with anticoagulants is being prepared for an operative intervention, the anticoagulants can be safely withheld for 5 doses preoperatively and then resumed the evening after surgery. This strategy may not be safe for those patients on warfarin therapy because of an artificial heart valve. In these high-risk patients, while warfarin is being withdrawn, intravenous heparin can be administered, holding it 6 hours before the operation and restarting postoperatively, continuing it until a therapeutic level of anticoagulation is achieved with warfarin. Low-molecular-weight heparins should be held for 12 hours before an operation and resumed 24 hours after the procedure, especially if spinal anesthesia is used. There is no standard for the management of antiplatelet agents. Traditionally, aspirin has been withheld for a week before surgery, but more recent data suggest that this practice is not needed to reduce bleeding complications. A large but nonrandomized study found dramatically lower rates of myocardial ischemia, gut ischemia, stroke, and kidney failure when aspirin is continued in the perioperative period in patients undergoing CABG. Importantly, in this study, the risk of bleeding and need for transfusions were not found to be increased in the patients who continued their aspirin. Randomized studies are needed to confirm the potential benefit of initiating or continuing aspirin in high-risk patients undergoing surgical procedures. For now, whether to continue, discontinue, or initiate aspirin is not clear.
As mentioned previously, renal and glomerular blood flow decreases with age. Concomitantly, there is a loss of muscle mass with age, such that an apparently normal serum creatinine may by misinterpreted as indicating normal kidney function. Glomerular filtration could be more accurately estimated by calculating the creatinine clearance using the Cockroft-Gault equation (see the section on elimination in Pharmacotherapy) or relying on the MDRD (Modification of Diet in Renal Disease study) method that some laboratories use to automatically calculate glomerular filtration rate. Since many drugs administered during the perioperative period may require dosage adjustments with diminished renal function, accurate estimation of glomerular filtration rate is important.
Also, because of decrements in the ability of the kidney to appropriately retain salt or to maximally concentrate or dilute urine in response to intravascular volume, the use of intravenous fluids needs to be monitored very carefully. Volume resuscitation is best achieved with normal saline or blood (if appropriate), since half-normal saline or water are hypotonic and more readily diffuse to the extravascular tissues. The combination of pain in a patient who is receiving nothing by mouth and receiving intravenous D5 half-normal saline inevitably produces hyponatremia in this setting. (See also the section on acute tubular necrosis in Kidney Diseases and Disorders.)
Delirium is a common and morbid event in the postoperative period. The type of surgery appears to be an important determinant of delirium, with incidence rates ranging from about 4% or 5% in cataract or urologic procedures to rates reported to be as high as 50% or 60% in some series of patients with infrarenal abdominal aortic aneurysm repair or hip fracture surgery. Both preoperative and intraoperative factors have been evaluated as risk factors for delirium. Preoperative factors in patients undergoing noncardiac surgery that predispose to postoperative delirium include: age 70 years or over, cognitive impairment, limited physical function, a history of alcohol abuse, abnormal serum sodium, potassium or glucose, intrathoracic surgery, and abdominal aneurysm surgery. The most important intraoperative factor found to be associated with delirium is intraoperative blood loss. Patients with a postoperative hematocrit < 30% had an increased risk of delirium (odds ratio = 1.7, 95% confidence interval 1.1 to 2.7) irrespective of the presence or absence of preoperative risk factors. When preoperative risk factors are present, the physician can identify patients at greatest risk for developing delirium and can be especially vigilant about correcting fluid, electrolyte and metabolic derangements, optimizing replacement of blood loss, maintaining circadian rhythms by getting patients out of bed during the day and minimizing sleep interruptions at night, and cautious drug prescribing. (See also the section on postoperative delirium in Delirium.)
Untoward effects of well-intentioned interventions are common among older hospitalized persons. Some of the more common pitfalls to be avoided include restricting mobility, excessive use of catheters, inattention to nutrition and hydration status, and inappropriate use of medications. Few disease states benefit from bed rest. It is important to maintain mobility and function as much as possible by encouraging time out of bed and avoiding restraints. The risks of skin breakdown, muscle atrophy, joint stiffness, and bone loss can be reduced by preserving mobility. Although bladder catheters can sometimes be critical in accurately measuring urine output, there is a substantial risk of infection with prolonged use of an indwelling catheter. These can also contribute to restricted mobility and should be removed as soon as possible. Restricted diets and lack of access to water can contribute to compromise in nutrition and hydration. Conversely, continued administration of intravenous fluids after the patient is able to maintain hydration orally can result in volume overload and impaired oxygenation. A regular review of medication administration can avoid unnecessary drug use and inappropriate dosing.
Surgery in elderly persons often results in destabilization of chronic, coexistent medical conditions. Additionally, because of the diminished physiologic reserve common in older persons, new medical problems may arise in the postoperative period. Some of the most common medical issues to contend with postoperatively are discussed here.
The most common cardiovascular problems that arise in older persons after surgery are hypertension, rhythm disturbances, and heart failure. Postoperative hypertension should initially prompt a search for a noncardiovascular cause, such as pain or urinary retention. Next, it is important to assess volume status, review fluid administration records, and note whether antihypertensive medications were mistakenly omitted before the procedure. To treat uncontrolled essential hypertension, parenteral formulations are available in several classes of medications: β-blockers, calcium channel blockers, angiotensin-converting enzyme inhibitors, and drugs that block both α- and β-adrenergic receptors. Topical agents, such as topical nitroglycerine, could also be considered useful in this setting.
Cardiac rhythm disturbances are concerning because they can lead to myocardial ischemia and heart failure. Supraventricular tachycardia, commonly seen in older persons, is associated with a history of prior supraventricular dysrhythmias, asthma, heart failure, and premature atrial complexes on a preoperative electrocardiogram. This rhythm disturbance is also more common in patients who have had vascular, abdominal, or thoracic procedures. Early restoration of sinus rhythm, or at least controlling the ventricular rate, can be attempted with an infusion of adenosine, a β-blocker, or a calcium channel blocker. If the rhythm is atrial fibrillation, conversion to sinus rhythm can be attempted with electrical cardioversion or by an infusion of amiodarone. Since spontaneous reversion to sinus rhythm often occurs within 6 weeks of the operation, long-term use of an anti-dysrhythmic like amiodarone may not be necessary. Persistent atrial fibrillation beyond 24 to 48 hours is associated with an increased risk of thromboembolism, and consideration should be given to anticoagulation therapy to reduce the risk of stroke.
Cardiac reserve is often compromised among older persons, especially those with longstanding hypertension or CAD. Heart failure may develop as a result of excessive fluid administration, or new cardiac ischemia or a rhythm disturbance. It can be extremely challenging to ensure optimal ventricular filling pressures on the basis of the clinical assessment of volume status in older persons by physical examination and standard laboratory parameters alone. Although some have recommended the use of pulmonary artery catheters in high-risk patients, studies have not shown a mortality benefit for this intervention.
Impaired preoperative kidney function increases the risk of postoperative kidney failure. The impaired reserve makes the aging kidney more susceptible to the effects of even transient reduction of cardiac output or brief exposure to nephrotoxic medications. When kidney damage has been sustained, early clinical manifestations include oliguria, isosthenuria, and an increase in serum creatinine. When impaired renal blood flow is the cause, the urine sodium will typically be less than 40 mEq/L and the urine-to-plasma creatinine ratio will be greater than 10:1. In contrast, if acute tubular necrosis is the mechanism of injury, the urine sediment may have granular or epithelial cell casts, and the urine sodium will be greater than 40 mEq/L with a urine-to-plasma creatinine ratio of less than 10:1. When acute tubular necrosis is suspected, vigorous efforts should be made to preserve kidney function by holding all potentially nephrotoxic medications and meticulously maintaining a euvolemic state. The indications for dialysis are no different in the perioperative period and include hypervolemia, hyperkalemia, metabolic acidosis, or encephalopathy. Another important mechanism of postoperative kidney failure is obstructive nephropathy, especially in older men with prostatic hyperplasia. The partial outflow obstruction combined with immobility and exposure to medications with anticholinergic effects compromising detrusor function all conspire to precipitate acute urinary retention. In addition to oliguria and an increase in serum creatinine, the bladder will typically be palpable because of distention. Treatment consists of insertion of a bladder catheter to reduce the risk of hydronephrosis and impaired kidney function. (See also the section on acute tubular necrosis in Kidney Diseases and Disorders.)
Constipation is quite common postoperatively, as a consequence of the combined effects of altered diet, immobility, and usually narcotic and other constipating medication use. At times, ileus and obstipation may be severe and produce significant anorexia, nausea, and even vomiting. The role of postoperative iron therapy to treat anemia is unproven and likely also contributes. Given the common co-occurrence of these risk factors for constipation in the postoperative period, a reasonable approach is to simultaneously order a stool softener every time a narcotic prescription is ordered, particularly if the patient has a history of constipation or it is reasonably anticipated that mobility will be reduced for more than 1 day. Prunes or prune juice, applesauce, and bran can all also have promotility effects. Table 14.2 lists the many medications useful in preventing and managing constipation.
Postoperative diarrhea should raise concern for fecal impaction and antibiotic-associated or Clostridium difficile diarrhea in the setting of recent antibiotic use. Checking manually for fecal impaction and sending stool specimens for leukocytes and C. difficile toxin may be appropriate. Management must focus carefully on volume resuscitation and treating the underlying cause.
Finally, nausea is not uncommon in the postoperative period, often as a result of narcotic, anesthetic, and other medications or slowed gut motility. See the section on nausea in Palliative Care for a discussion on approach to management.
Type 2 diabetes mellitus is a common comorbid condition of many older persons undergoing surgery. Usually, given the long half-life of oral hypoglycemic agents and the nothing-by-mouth status for surgery, oral diabetes drugs are held the day of surgery. It may be especially important to hold metformin, given the potential additional risk of metabolic acidosis from this drug during a time of stress. To optimize glucose control, an intravenous solution containing glucose can be administered at a constant rate while blood glucose by finger stick assay is closely monitored, administering subcutaneous insulin as necessary to control glucose levels until the patient is able to resume eating. A type 2 insulin-using diabetic patient should have her insulin held on the day of surgery and receive sliding-scale insulin. Once the patient is able to advance her diet, usually half the outpatient dose of diabetes drugs are administered the first day of oral intake, with additional sliding-scale insulin coverage as needed, and then full doses are resumed as the patient consumes a usual diet. Notably, there is currently no evidence that rigorous control of blood glucose in the perioperative period provides benefit in terms of recovery of function, reduction of infections, or wound healing; thus, “permissive moderate hyperglycemia” may be prudent until adequate oral intake is ensured.
Patients taking supplemental corticosteroids require special consideration during the perioperative period. Those taking more than 20 to 30 mg of prednisone daily for more than a week or with known adrenal insufficiency should be given “stress doses” of steroids perioperatively. A single measure of cortisol, if elevated, is useful to assess the hypothalamic-pituitary axis (HPA) in patients who chronically use steroids when the function of the HPA is in question. If the cortisol level is not high, a 30-minute ACTH test may be useful. The dose of steroids to use is debated, but some authorities advise the equivalents of 25 mg of hydrocortisone the day of surgery only for minor procedures, 50 to 75 mg hydrocortisone equivalents daily (for example, hydrocortisone 20 mg intravenously every 8 hours) for 1 to 2 days for moderate surgical stress, and 100 to 150 mg hydrocortisone equivalents daily (for example, hydrocortisone 50 mg intravenously every 8 hours beginning within 2 hours of surgery) continuing for 2 to 3 days postoperatively, and then transitioned to the usual steroid regimen for high surgical stress. Other authorities simply recommend continuation of usual doses of steroids for elective, uncomplicated surgeries, or doubling or tripling the outpatient dose by giving hydrocortisone intravenously up to 100 to 150 mg daily for higher risk or anticipated complicated operations.
Delirium is one of the most common postoperative complications, and certainly the one for which a geriatrician is most likely to be consulted. In a randomized study, a multicomponent intervention, focusing on reducing sleep interruptions, minimizing medications and immobility, enhancing sensory input, and reducing dehydration was found to reduce the rate of developing delirium by one third over standard care for hospitalized medical patients. This approach, though not specifically studied in the postoperative setting, is likely to be beneficial in the postoperative phase as well. See “Delirium for descriptions of risk factors for delirium and a reasonable approach to diagnosis, evaluation, and treatment. For the postoperative geriatric surgical patient, undertreated pain, constipation, electrolyte abnormalities, and perioperative myocardial infarction must be particularly considered.
Postoperative cognitive decline can be subtle or dramatic and is considered to be a syndrome distinct from delirium characterized by abnormalities in learning and memory. It has been reported most commonly after cardiac surgery but is experienced by patients undergoing procedures that do not involve extracorporal circulation. Although the symptoms are often short-lived, they persist for many months in 10% to 30% of patients. Efforts to define the cause of the syndrome have not yet been successful; studies have not been able to demonstrate links with hypotension, hypoxemia, or type of anesthesia. Lacking a better understanding of the pathophysiology, treatment efforts are supportive.
Management of postoperative pain remains a challenge, particularly in the patient with dementia, delirium, or both. The key points to the evaluation and management of acute pain are quite similar to those discussed in Persistent Pain, and Table 19.1, Common Pain Behaviors in Cognitively Impaired Elderly Persons, provides a useful guide to the tools to assist in assessment of postoperative pain in cognitively impaired patients. The oldest-old and cognitively impaired patients appear to be at highest risk for undertreatment of pain, so they deserve particular attention. Undertreatment of pain, at least in nondemented individuals, appears in fact to be a more powerful predictor of the development of postoperative delirium than narcotic use.
Most postsurgical pain will require therapy with narcotic analgesia. Cognitively intact patients may have improved pain relief and overall lower use of narcotics if drugs are administered by patient-controlled analgesia (PCA) pump. Individuals with less severe pain may be able to tolerate scheduled acetaminophen (not to exceed 4 g a day) with only as-needed use of narcotic analgesics, if they are able to ask for them. Patients who are unable to communicate effectively and have pain should be given standing orders for narcotic analgesics, with guidelines as to when to hold the medications, combined with frequent assessment of medication effect. Nonsteroidal anti-inflammatory medications are best avoided in this setting. Recall that narcotic analgesics may precipitate constipation; thus, concomitant use of stool softeners is generally advised. See the Web site for Geriatrics At Your Fingertips for comprehensive, up-to-date information on pain medications and dosing at http://www.geriatricsatyourfingertips.org.
Nonpharmacologic therapies, such as ice packs, heating pads, massage, and relaxation techniques, are also useful adjuncts to therapy.
Geriatricians and internists can significantly aid patients by anticipating and planning for transitions in care. Well before the time of discharge, it is important to understand how the patient will get help if he or she returns home. Watching a patient transfer, walk, and perform activities of daily living will help guide choices about appropriate discharge destination and home services that would be required to maximize a safe transition.
The time of transition is also treacherous in terms of medication errors. Carefully review with the patient (or her caregiver) her diagnoses, the summary of her hospital course, what specific medications she should take at home, and which of her old medicines she should discontinue. Include any special instructions about dosing and timing of the medication; also assess whether she will be able to obtain and administer her medications appropriately. It is useful to make sure that she (or her caregiver) understands the basics about how to manage her disease and the treatments and the need for the follow-up appointments; it should also be clear who is responsible for scheduling these appointments. Because geriatric patients tend to be more complex, it may be useful to facilitate the transition by communicating directly with the next care provider, especially for those patients who are being discharged to another institutional setting.
■ Arozullah AM, Khuri SF, Henderson WG, et al. Development and validation of a multifactorial risk index for predicting postoperative pneumonia after major noncardiac surgery. Ann Intern Med. 2001;135(10):847–857.
This investigation used a database of more than 160,000 veterans to derive and validate a clinical prediction model for postoperative pneumonia in noncardiac surgical patients. Patients were divided into five risk classes by the use of risk index scores. Pneumonia rates were 0.2% among those with 0 to 15 risk points, 1.2% for those with 16 to 25 risk points, 4.0% for those with 26 to 40 risk points, 9.4% for those with 41 to 55 risk points, and 15.3% for those with more than 55 risk points. The postoperative pneumonia risk index evidently identified patients at risk for postoperative pneumonia and may therefore be useful in guiding perioperative respiratory care.
■ Eagle KA, Berger PB, Calkins H, et al. ACC/AHA guideline update for perioperative cardiovascular evaluation for noncardiac surgery—executive summary. Circulation. 2002;105(10):1257–1267. Also available at: http://www.acc.org and http://www.americanheart.org (both accessed October 2005).
This document is an update of the original evidence-based guidelines distributed from the American College of Cardiology and the American Heart Association in 1996. Recommendations for evaluation of perioperative cardiac risks and perioperative management of cardiac conditions are provided and graded on the level of supporting evidence found. This is a useful reference with a framework provided that is widely used by clinicians. The guidelines do not specifically pertain to geriatric patients, but to all adult patients. The authors conclude that preoperative testing should be limited given the lack of evidence that widespread use positively alters outcomes. The guidelines are reviewed and updated annually on the Web sites.
■ Geerts WH, Pineo GF, Heit JA, et al. Prevention of venous thromboembolism: the Seventh ACCP Conference on Antithrombotic and Thrombolytic Therapy. Chest. 2004;126(3 Suppl):338S–400S.
This is a comprehensive review of the evidence base for and guidelines for the use of antithrombotic and thrombolytic therapies for all indications. The sections on the use of these therapies to prevent deep-vein thrombosis in for patients planning various surgical procedures is particularly informative and is presented with a grading of the strength of the evidence base.
■ McFalls EO, Ward HB, Mortitz TE, et al. Coronary-artery revascularization before elective major vascular surgery. N Engl J Med 2004;351(27):2795–2804.
This prospective, randomized clinical trial entitled Coronary Artery Revascularization Prophylaxis (CARP) investigated coronary revascularization (either by angioplasty or bypass surgery) versus no revascularization before elective repair of either an expanding abdominal aortic aneurysm or of severe arterial occlusive disease of the legs. All patients had stable coronary artery disease and had coronary angiograms, and they were eligible for study if one or more major coronary artery had a stenosis of at least 70% suitable for revascularization. Patients were excluded if they had a left main occlusion greater than 50% and ejection fraction of less than 20%, or had severe aortic stenosis. There were no differences between the two groups in postoperative cardiac infarction, early postoperative death, hospital length of stay, or mortality for the 2.7 years of follow-up, and the revascularized group had a significant delay until the elective vascular surgery was performed. Thus, even in high-risk patients, preoperative revascularization should be reserved for patients with conditions that otherwise would warrant revascularization (unstable cardiac symptoms, significant left main disease, or multivessel disease with a low ejection fraction) regardless of the proposed surgery.
■ Marcantonio E, Flacker JM, Wright RJ, et al. Reducing delirium after hip fracture: a randomized trial. J Am Geriatri Soc. 2001;49(5):516–522.
This is a prospective randomized clinical trial involving 126 consenting and eligible patients admitted for acute hip fracture comparing “proactive” geriatrics consultation versus usual care. The intervention patients were seen by the geriatrician within 24 hours after surgery, though most were seen preoperatively. Orthopedics adherence with geriatrics recommendations was high (77%) and resulted in a one third reduction in the rate of developing delirium, though without impact on length of stay. This study demonstrated that collaborative and proactive efforts are effective in reducing postoperative delirium.
■ Smetana GW. Preoperative pulmonary evaluation. N Engl J Med. 1999;340(12):937–944.
This review article represents an excellent overview of the salient issues regarding the preoperative pulmonary evaluation in both young and old patients. This is a common source of consultation for internists. It is particularly important to understand the limitations of the current literature, main risk factors for postoperative pulmonary complications, and prudent postoperative maneuvers to minimize this particularly hazardous occurrence in the course of older patients’ lives.
Colleen Christmas, MD
Peter Pompei, MD