Preoperative Evaluation and Medical Optimization of the Cancer Patient

Introduction

Although many of the goals of preoperative evaluation and optimization are the same for patients with and without cancer, cancer patients present a unique set of challenges that perioperative physicians must be familiar with. The overall goals of preoperative evaluation are to understand the whole patient, identify undiagnosed or undertreated conditions, and acknowledge patient- and procedure-related risk factors in order to prepare the patient optimally for surgery. A comprehensive preoperative evaluation lays the groundwork for high-quality care of the surgical patient. Additionally, a comprehensive preoperative evaluation of the cancer patient lends insight into potential risks and complications that may occur in the postoperative period.

History and Physical Examination

For all patients, the preoperative evaluation should involve information gathering through history taking, review of medical records, diagnostic testing, and a focused physical examination. All medications must be reviewed and confirmed with the patient. The history of each medical condition should be reviewed in detail to develop an understanding of the level of control of each and to determine if additional treatment or optimization is needed. The physical examination should be focused as to add insight into findings from the review of the history.

For cancer patients, it is especially important to take a detailed history that includes initial presenting symptoms and how the diagnosis of cancer was made. A thorough review for any history of cancer and prior cancer treatments should be conducted. As treatment of cancer is, more often than not, multi-disciplinary, it is of particular importance to note current treatment in the neoadjuvant period. Recent cancer treatment, including chemotherapy and radiation therapy, must also be reviewed as these may have systemic effects relevant to perioperative management (addressed elsewhere). It is important to note that recent imaging should be reviewed in order to understand the nature of any solid tumors and other organ involvement that may impact perioperative care (e.g., head or neck tumor compromising the airway). Care should be taken to ensure that the physical examination includes findings related to the area of tumor involvement, and these findings should be documented carefully (for example, hepatomegaly in liver cancer).

Preoperative Testing

In general, routine preoperative testing should not be performed. Institutional policies that mandate blanket testing for all patients should be avoided. Laboratory tests and other diagnostic testing should be performed only if indicated based on patient factors and if results are anticipated to affect or improve management. This should generally also apply to cancer patients. Given the systemic effects of cancer and cancer treatments, it is likely that many cancer patients will warrant some preoperative testing based on focused history and physical examination findings if it has not been done already. It would be prudent to check laboratory markers for nutrition in the patient who presents with a gastrointestinal malignancy and weight loss. Likewise, patients with a history of radiation therapy to the neck may need testing of thyroid function and possibly vascular studies if carotid bruits are present. ^, Additionally, if a patient has experienced a side effect or complication due to recent treatment, it is prudent to check for laboratory studies that may be abnormal. For example, a patient who has experienced nausea and vomiting after chemotherapy and just prior to surgery might have electrolyte derangements that need correcting.

Preoperative evaluation may take many different forms. Some institutions may rely on the patient’s usual primary care physician to provide a preoperative evaluation, while many large academic institutions have highly developed preoperative evaluation clinics staffed by practitioners with training and experience in perioperative medicine. These clinics are often a key component in facilitating coordinated perioperative care and enrollment of patients in preoperative pathways (addressed elsewhere). There are numerous reports of potential benefits of a dedicated preoperative clinic and interdisciplinary coordinated care, with some studies citing improvement in patient satisfaction, decrease in unnecessary testing and consultations, reduction in surgical delays and cancelations, shorter length of stay, fewer postoperative complications, and even reduced in-patient mortality. ^, Although a preoperative evaluation is a requisite for surgery, there is no consensus on a superior method for accomplishing this, and it ultimately depends on the resources and priorities of the institution where the surgery will be performed.

One of the major principles that must be kept in mind for cancer patients is that cancer surgery is not usually truly elective. The time-sensitive nature of cancer surgery means that careful attention must be paid to avoid preoperative management plans that would unnecessarily delay surgical treatment. The benefit of performing additional tests or delaying surgery for better control of a medical condition must be weighed against the risk of cancer progression and a potentially worse prognosis that may develop in the interim. Collaboration between the oncologist, surgeon, anesthesiologist, primary care physician, and other specialists is especially important in this case to determine the optimal time to proceed with surgery. A useful concept in evaluating patients facing cancer is the multihit hypothesis for cancer deconditioning ( Fig. 14.1 ). Perioperative physicians should identify potential concerns along the domains of prior treatment, age and sarcopenia, medical comorbidities, sedentary lifestyle, and cancer fatigue.

Cardiovascular Risk Assessment

As in preoperative evaluation of all surgical patients, assessment of risk for cardiovascular events should be performed for all cancer patients planning for surgery. In general, the stepwise approach provided in the 2014 ACC/AHA Guideline on Perioperative Cardiovascular Evaluation and Management of Patients Undergoing Noncardiac Surgery can be applied. The first step of the approach for cancer patients planning for nonemergent surgery will be to estimate the risk of major adverse cardiac events (MACE) for the combined clinical/surgical risk. The 2014 ACC/AHA guidelines recommend the use of the Revised Cardiac Risk Index (RCRI) or the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) calculator to determine if the risk is low (<1%) or elevated. If the risk is low then no further testing is indicated. If the risk is elevated then functional capacity should be assessed. If it is determined that a patient can achieve four metabolic equivalents (METs) or more, then no further testing is indicated. If the patient cannot achieve four METs or if functional capacity is unknown, then additional cardiac testing is considered only if the results of testing will change the management (i.e., delay surgery for revascularization, choose alternative management strategy, or decide not to proceed with surgery).

Studies have previously suggested that subjective assessment with self-reported exercise tolerance is predictive of cardiovascular complications, and this has been a commonly used method of determining whether the patient requires further cardiac workup prior to surgery. With the publication of the results of the multicenter, international, prospective cohort METS study, the reliability of subjective assessment of exercise tolerance is now being questioned. When compared with subjective assessment of exercise tolerance, only the Duke Activity Status Index (DASI) was found to be predictive of death or myocardial infarction within 90 days of surgery. Based on the results of the study the authors recommend that given the lack of predictive ability found, subjective assessment of exercise tolerance no longer be used. How this finding will be applied in future recommendations is not yet known.

Pulmonary Risk Assessment

In regard to perioperative evaluation of the patient presenting with dyspnea and/or chest pain, it is especially important to obtain a history that includes details of recent treatment. Numerous treatments can affect the cardiopulmonary system, and it is important to determine if symptoms existed prior to treatment or developed during treatment. Patients with preexisting symptoms may have known or undiagnosed cardiovascular conditions, and targeted testing should be performed. For patients who develop dyspnea and/or fatigue during neoadjuvant treatment, it is important to discern if the treatment itself has cardiotoxic or pulmotoxic side effects. If a previously healthy and active patient has developed these symptoms and has not received treatment that may affect the cardiopulmonary system, it is reasonable to assume that cancer treatment–associated fatigue is the etiology behind the deconditioning and the patient may proceed to surgery.

The Older Patient

In 2012 the American College of Surgeons and the American Geriatrics Society released best practices guidelines for preoperative assessment of the geriatric patient, which recommends screening for frailty, cognitive impairment, and nutrition. All cancer patients considering surgery should be screened for nutritional status. Older cancer patients planning for major surgery should also be screened for frailty and cognitive impairment. Frailty is a better predictor of mortality, complications, and prolonged length of stay in older surgical patients than chronological age. Although screening for these risk factors is clearly recommended, interventions for management once the patient has been screened are emerging and many hospitals are not yet equipped to provide additional resources that might be of benefit. Patients who have been identified as frail and planning major surgery should undergo a comprehensive geriatric assessment with a specialist in geriatrics. Additional benefit may be gained for frail patients with early involvement of a multidisciplinary comanagement team involving social workers and geriatrics specialists. ^, A multimodal prehabilitation program may benefit patients with these risk factors as well (addressed elsewhere).

Certain types of cancer and cancer treatments will require that special attention be paid to specific features preoperatively in order to facilitate carefully coordinated intra- and postoperative management (cancer therapies and perioperative implications addressed elsewhere). This is especially important for cancers that have the potential to cause airway compromise or hemodynamic disturbance intraoperatively.

Cancer-Specific Concerns

Patients with head and neck cancer warrant a detailed airway examination ideally by a practitioner experienced in airway management. A careful history should be performed to elicit symptoms that may suggest airway involvement, such as dyspnea, stridor, and voice change. Imaging should also be carefully reviewed preoperatively. Normal anatomic landmarks may be obscured, and a preoperative examination should be performed to document any abnormalities that might suggest difficult airway management (addressed in detail elsewhere).

Similarly, a patient with solid tumor with involvement of major cardiovascular or airway structures must be carefully assessed preoperatively with a review of imaging. Especially in the case of anterior mediastinal and other large intrathoracic masses, careful communication and coordination between the surgeon and anesthesiologist preoperatively is imperative in order to ensure plans for intraoperative management, should severe hemodynamic or airway disturbances occur.

Presence of malignant ascites or pleural effusions may have significant hemodynamic and respiratory significance during anesthetic management. Especially if drainage of ascites is planned intraoperatively, fluid needs to be carefully managed intraoperatively. Patients may benefit from preoperative drainage of fluid to prevent large fluid shifts or difficulty with ventilation intraoperatively.

Anemia is frequently seen preoperatively in cancer patients. It is usually multifactorial, as it can be related to blood loss, hemolysis, underlying hereditary disease, renal insufficiency, nutritional deficiency, chronic disease, cancer treatment, or a combination of these. Cancer patients should be screened for anemia early and treatment started as soon as possible to avoid transfusion of blood products whenever possible (addressed elsewhere).

Conclusion

As previously stated, medical comorbidities, including cancer treatment–related side effects, should be carefully noted and commented on for perioperative management concerns. The preoperative visit should also be viewed as a chance to impact those lifestyle behaviors that correlate with poorer outcomes, such as smoking and sedentary lifestyle. The perioperative consultation should also highlight immediate medical management concerns such as anticoagulation and management of devices, including, but not limited to, pacemakers, defibrillators, and insulin pumps. In summary, a thoughtful and concise perioperative evaluation of the cancer patient should anticipate potential complications from the cancer itself, previous cancer treatment, and medical comorbidities for the patient undergoing surgery.