Anesthesia-Specific Issues
16.1 Appropriateness, Informed Consent, and Shared Decision Making
Matthew B. Allen
Angela M. Bader
The pursuit of appropriate, high-value surgical care is an increasingly important focus of health policy discourse. At a basic level, “appropriate care” entails that the intervention offer the patient benefits in excess of harm. Risk/benefit analysis has never been straightforward, but it has become even more complex with recognition that the relative importance of risks and benefits depends on patient-specific preferences and values. We contend that the task of ensuring surgical appropriateness is inextricable from the process of developing patient-centered, shared decision-making processes in the preoperative setting. In addition to undermining quality and value, inappropriate care is a threat to the ethical integrity of surgical practice. In this chapter, we clarify the central concepts of shared decision making, review empirical evidence describing performance in these domains, and outline promising directions for innovation and preoperative quality improvement.
CENTRAL CONCEPTS
Physicians are bound by ethical principles including beneficence (the obligation to contribute to patients’ welfare) and nonmaleficence (the obligation to avoid doing harm) (1). These principles are today reflected in the concept of “appropriateness,” which refers to a favorable ratio of expected benefits to expected harms. Beyond outcomes, appropriateness also encompasses considerations of cost. A high-value procedure offers a favorable outcome at a cost considered to be worthwhile based on the degree of likely benefit (2). Existing methods of ensuring appropriateness of surgical care have attempted to maximize benefit and minimize harm by incorporating clinical evidence, surgeon qualifications, and hospital certification. Notably absent from these approaches is attention to whether the procedure is consistent with the patient’s overall preferences and values (Fig. 16.1).
In its 2001 report, Crossing the Quality Chasm, the Institute of Medicine (IOM) named patient-centered care as a key to improving health care quality, defining it as “providing care that is respectful of and responsive to individual patient preferences, needs, and values, and ensuring that patient values guide all clinical decisions” (3). Implied in this definition is a collaborative process between patients and providers to elicit and incorporate patient values in medical decisions.
Shared decision making is best understood in contrast to alternative ways of conceptualizing medical decision making, particularly the paternalistic model and the informed
decision-making model (4). Under the paternalistic model, the physician employs his expertise in service of what he perceives to be the patient’s best interest. The patient’s role is passive, and the physician decides on the best course of action. The informed decision-making model involves the physician providing relevant technical information to the patient (e.g., risks, benefits, clinical effectiveness, alternatives), and then allowing the patient to decide for themselves based on their own values and preferences. Following this transfer of information, the physician’s role is passive (so as to avoid encroaching on the patient’s autonomy), and the patient decides on the best course of action.
decision-making model (4). Under the paternalistic model, the physician employs his expertise in service of what he perceives to be the patient’s best interest. The patient’s role is passive, and the physician decides on the best course of action. The informed decision-making model involves the physician providing relevant technical information to the patient (e.g., risks, benefits, clinical effectiveness, alternatives), and then allowing the patient to decide for themselves based on their own values and preferences. Following this transfer of information, the physician’s role is passive (so as to avoid encroaching on the patient’s autonomy), and the patient decides on the best course of action.
 Figure 16.1 Components of high-quality surgical decision making. (Cooper Z, Sayal P, Abbett SK, et al. A conceptual framework for appropriateness in surgical care: reviewing past approaches and looking ahead to patient-centered shared decision making. Anesthesiology. 2015;123:1450-1454. |
Both the paternalistic model and the informed decision-making model acknowledge asymmetry in what the physician and the patient bring to the encounter (the physician offers clinical expertise, while the patient is knowledgeable about their concerns/values), but neither model achieves truly shared decision making (5). At the very least, shared decision making entails the following (adapted from Charles et al. (5)):
Communicating with patients about the risks and benefits of possible interventions
Eliciting patients’ goals, values, and concerns
Assisting patients in how to conceptualize the risks and benefits/how to approach the decision
Communicating with patients about risks and benefits is part of the process of obtaining informed consent, a necessary but not sufficient feature of shared decision making. Legal requirements to obtain consent for interventions date back to the 1914 case Schloendorff v Society of New York Hospital, in which the court decided that performing surgery without permission constitutes a form of battery (6). Since that time, ethical standards surrounding informed consent have incorporated a broader set of issues including questions of capacity to make decisions, disclosure of relevant information, ensuring patient understanding of that information, and voluntariness (1). Perspectives on what information is relevant and necessary to discuss have become increasingly patient-centered. The standard of care was once to disclose only information that a reasonable physician would disclose given the circumstances (the reasonable physician standard). Now, many states have adopted a “reasonable-patient” standard, which dictates that physicians share all information that a patient might find relevant in weighing their options (7). Specific recommendations regarding informed consent policies and processes can be found in the Recommendations section.
Beyond communicating information and obtaining informed consent, shared decision making entails active engagement with patients about their goals, values, and concerns (5). The appropriateness of a procedure depends not only on the risks and benefits described in empirical research, but also on how the possible outcomes fit into patients’ experience of disease and their personal goals. It is therefore essential to facilitate the patient’s process of imagining possible outcomes and their importance for patient’s quality of life. Shared decision making is not simply a matter of highlighting relevant information about the procedure and the patients’ values. It also entails assisting the patient in how to establish priorities and use those priorities to reach a decision.
Studies have highlighted an important relationship between shared decision making and high-value care (8). Patients who participate in a robust decision-making process focused on their goals and values are more likely to choose conservative management options with associated reductions in cost (9,10). Multiple analyses have therefore suggested that widespread implementation of shared decision making can result in significantly fewer surgeries and increased savings (9,10). Provided that these decisions are truly consistent with patients’ preferences, implementing shared decision making is a promising mechanism for enhancing the value of surgical care.
An increasingly recognized domain of shared preoperative decision making is the intra- and postoperative management of do-not-resuscitate (DNR) orders. The IOM has called patient-centered end-of-life decision making a “national priority,” and the American College of Surgeons (ACS) and the American Society of Anesthesiologists (ASA) recently advocated preoperative clarification and documentation of patients’ preferences regarding postoperative care (11,12,13). Consent for intraoperative intubation and mechanical ventilation should not imply consent for prolonged intensive care or aggressive management of possible complications. As with the process of ensuring patients’ understanding of risks and benefits and eliciting their preferences, clarifying patients’ preferences for postoperative cardiopulmonary resuscitation and intubation is a complex goal that is rarely achieved in practice. See Chapter 13.5.
CURRENT PRACTICE
Evidence suggests the quality of surgical decision making is often limited in the domains of patient understanding, incorporation of patients’ values, and advance care
planning. For example, in a study of over 1,000 preoperative patients, 8% could not identify their diagnosis, 10% could not identify their procedure, and 7% reported that they did not know the risks and benefits of different options (14). Other studies have suggested even lower rates of understanding/recall. Only 48% of vascular surgery patients were able to demonstrate knowledge of risks and potential complications and orthopedic surgery patients’ recall of specific potential complications ranged from 37% to 61% (15,16).
planning. For example, in a study of over 1,000 preoperative patients, 8% could not identify their diagnosis, 10% could not identify their procedure, and 7% reported that they did not know the risks and benefits of different options (14). Other studies have suggested even lower rates of understanding/recall. Only 48% of vascular surgery patients were able to demonstrate knowledge of risks and potential complications and orthopedic surgery patients’ recall of specific potential complications ranged from 37% to 61% (15,16).
Given that surgical decision making falls short of basic standards of informed consent in many cases, it is unsurprising that the process also frequently fails to incorporate patients’ values and concerns. In a study of over 2,000 breast cancer surgery patients, 50% of women reported that reducing disease recurrence was an important factor in their decision-making process. Despite knowing that disease recurrence was a factor that mattered to them, a significant majority of patients were unaware that local recurrence rates differed between breast-conserving surgery and mastectomy (17). Other surgical patients fail to develop a clear sense of which risks and benefits are most important to them, and some remain unsure of which option is best for them even after signing informed consent documents (14). Such deficits in decision making may help account for intensity of care at the end of life: nearly one-third of elderly Americans undergo surgery in the last year of life, most within the last month (18).
The data describing advance care planning are similarly discouraging. One study indicated that medical patients were 22 times more likely to have notes relating to end-oflife care than were surgical patients (19). Another study of advance care planning before elective surgery found that nearly two-thirds of patients had not completed an advance directive, and even among the patients who had completed one, nearly a third were missing from the chart. Roughly half had a health care proxy on file, and almost one-third reported a desire to talk further about advance care planning (14). Surgeons performing high-risk operations rarely discuss the potential need for prolonged mechanical ventilation/intensive care or elicit patient preferences about postoperative treatments (20). This well-established pattern is at odds with the ASA and ACS guidelines recommending preoperative discussion and implications of DNR orders to intra- and postoperative care (12,13,21). These deficits are a reflection of training as well as culture: a minority of residents express feeling comfortable performing key tasks such as conducting family meetings, and discussing code status and transitions to comfort care (22).
FUTURE DIRECTIONS
Though alarming, the data above indicate significant opportunities for innovation and leadership in the pursuit of improved preoperative decision making. In the section that follows, we review promising developments and areas of active research.
Decision Aids
Decision aids are evidence-based tools for educating patients and aligning care with patient preferences. The primary aims of decision aids are as follows (adapted from the International Patient Decision Aids Standards Collaboration) (23):
State the decision the patient is facing.
Communicate evidence-based information regarding the underlying medical condition as well as the management options, including risks, benefits, and areas of uncertainty.
Assist the patient in making a decision by describing risks and benefits in such a way that patients can (a) imagine the possible physical and emotional effects of surgery and (b) consider what matters most to them (23).
A recently updated Cochrane review suggests decision aids improve knowledge of management options and risk perception, reduce decisional conflict, promote patient involvement in decision making, and increase agreement between care and patients’ values (9). Section 3506 of the Affordable Care Act includes provisions to facilitate their adoption and further development, and it has been proposed that documented use of decision aids can be implemented as a quality metric tied to Medicare payments (8).
The Perioperative Surgical Home Model
Enacting shared decision making requires an environment and care infrastructure designed for this task. The Perioperative Surgical Home (PSH) Model is a promising approach intended to work via several mechanisms. First, it aims to engage patients in decision making about their care by eliciting their goals and educating them about proposed interventions. Second, it involves coordination of care by providers with diverse expertise and contributions to patient care. And third, it takes responsibility for optimizing the patient’s experience throughout the entire perioperative trajectory (24). Though ambitious, implementation of the PSH may be increasingly feasible given introduction of Medicare incentives supporting advance care planning and shared decision making.
Specific tasks of the PSH in the preoperative phase that have been proposed include (adapted from Vetter et al. (24)):
Identifying, communicating, and minimizing patient-specific risks using evidencebased protocols (e.g., medical optimization with beta blockers and statins)
Educating patients prior to surgery to diminish anxiety and optimize recovery
Developing plans for individualized postoperative pain management
Medical Education and Training
Reshaping surgical decision-making processes requires not only new tools and infrastructure, but also new skills and sensibilities. As suggested above, implementation of the PSH model requires anesthesiologists to adopt a new role as a “perioperativist” charged with engaging patients, family, and care providers in robust decision-making processes (24). Innovations such as structured training and Objective Structured Clinical Exams (OSCEs) are necessary to ensure competency in discussing code status and eliciting broader treatment goals. For example, use of online video content offering examples of effective versus ineffective communication led to improvements for low-performing residents and prevented skills degradation in high-performing residents (26). Offering more structured interdisciplinary experiences in undergraduate and graduate medical education can prepare trainees to work in the interdisciplinary environments necessary to enact shared surgical decision making. Thoughtful approaches to resident education will be crucial in enacting culture shifts toward shared accountability for surgical outcomes and engaging patients in shared decision-making processes.
Measurement
Developing measures of decision quality is an essential task for several reasons. First, measurement is necessary to evaluate the effectiveness of innovations intended to enhance shared decision making. Second, it can facilitate use of payment incentives to drive implementation of evidence-based strategies. And finally, measurement tools will be necessary to identify populations at risk of experiencing low-quality decision-making processes and their negative sequelae.
How do we determine whether high-quality decision making has taken place? A high-quality decision is one that reflects the values and preferences of a wellinformed patient (27). One conceptual framework for evaluating shared decision making is based on the Donabedian model and incorporates three domains (Fig. 16.2) (14,28):
Structure (knowledge of procedure and risks/benefits)
Process (patient comfort with the extent of discussion about the decision)
Outcome (patient certainty that the decision is right for them)
Rather than focus on outcomes related to the decision-making process itself, another approach highlights more conventional perioperative outcomes, namely pain intensity, health-related quality of life, quality of recovery, and patient satisfaction (29). Whether patient satisfaction serves as a meaningful measure of decision quality is unclear, as scholars have noted that answers to questions measuring satisfaction are driven by patient expectations and are therefore at best an indirect measure of decision support (30). Nevertheless, novel assessment tools developed using a mixed methods approach to exploring surgical patients’ views may be a promising direction for further study (29). Despite its importance in guiding innovation, the process of developing and validating tools for measurement of decision quality is in its infancy.
RECOMMENDATIONS
At a minimum, hospitals must develop informed consent policies to adhere to regulatory standards outlined by the Centers for Medicare and Medicaid Services and The Joint Commission (31,32,33) (Table 16.1). Institutions must also be attentive to their own states’ standards for obtaining and documenting informed consent.
 Figure 16.2 Conceptual model for measuring quality of preoperative decision making. ACP, advanced care planning. |
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Beyond developing necessary policies, institutions must develop systems for operationalizing them and integrating them into everyday practice. It is necessary to communicate professional standards to providers (e.g., through training and making requirements easily accessible via hospital intranet) and outline structures of accountability regarding how, where, and by whom consent will be obtained. Standardizing these practices is an important means of ensuring that necessary documentation is completed prior to surgery.
Though necessary, documentation of informed consent is not sufficient to ensure that decision-making processes include adequate assessment of patient understanding or integration of patient values. The next step will entail overcoming known barriers to shared decision making such as provider attitudes, inadequate training, and perhaps most importantly, time pressure and competing demands on clinicians’ time (34). Using tools to facilitate structured discussion of treatment preferences is a promising way to make shared decision making more feasible (35). Integrating decision support tools into the clinical workflow will likely require system-based approaches that do not rely on clinicians to facilitate access to decision support tools. For example, developing an infrastructure for (1) proactively identifying patients who might benefit from decision support and (2) initiating access to decision support tools in advance of a clinical encounter may be a mechanism for surmounting barriers to wider implementation of shared decision making (34).
Ultimately, the trajectory of innovation to enhance decision making in the preoperative setting as discussed in the previous section called “Future Directions” will depend on how we conceptualize our role as anesthesiologists. Is our preoperative responsibility limited to obtaining consent for anesthesia, or do we also have a responsibility to optimize surgical decision making in an effort to limit low-value, inappropriate care?
CONCLUSION
The task of ensuring surgical appropriateness is inextricable from the process of developing patient-centered, shared decision-making processes in the preoperative setting. The associated challenges present a significant opportunity for anesthesiologists to adopt a leadership role in enhancing the value, quality, and ethical integrity of surgical practice.
REFERENCES
1. Beauchamp T, Childress J. Principles of Biomedical Ethics. 6th ed. New York: Oxford University Press; 2009.
2. Cooper Z, Sayal P, Abbett SK, et al. A conceptual framework for appropriateness in surgical care: reviewing past approaches and looking ahead to patient-centered shared decision making. Anesthesiology. 2015;123:1450-1454.
3. Institute of Medicine. Crossing the quality chasm: a new health system for the 21st century. Washington, DC: National Academies Press; 2001.
4. Emanuel EJ, Emanuel LL. Four models of the physician-patient relationship. JAMA. 1992;267(16):2221-2226.
5. Charles C, Gafni A, Whelan T. Shared decision-making in the medical encounter: what does it mean? (or it takes at least two to tango). Soc Sci Med. 1997;44:681-692.
6. Schloendorff v Society of New York Hospital 211 N.Y. 125,105 (N.E. 92 1914).
7. Spatz ES, Krumholz HM, Moulton BW. The new era of informed consent: Getting to a reasonable-patient standard through shared decision making. JAMA. 2016;315:2063-2064.
8. Lee EO, Emanuel EJ. Shared decision making to improve care and reduce costs. N Engl J Med. 2013;368:6-8.
9. Stacey D, Bennett CL, Barry MJ, et al. Decision aids for people facing health treatment or screening decisions. Cochrane Database Syst Rev. 2011;10:CD001431.
10. Arterburn D, Wellman R, Westbrook E, et al. Introducing decision aids at Group Health was linked to sharply lower hip and knee surgery rates and costs. Health Aff (Millwood). 2012;31:2094-2104.
11. Institute of Medicine. Dying in America: Improving Quality and Honoring Individual Preferences Near the End of Life. Washington, DC: The National Academies Press; 2015.
12. American Society of Anesthesiologists Committee on Ethics. Ethical guidelines for the anesthesia care of patients with do-not-resuscitate orders or other directives that limit treatment. 2013. Available at http://www.asahq.org/For-Members/Standards-Guidelines-and-Statements.aspx.
13. Statement on advance directives by patients: ‘do not resuscitate’ in the operating room. Bull Am Coll Surg. 2014;99:42-43.
14. Ankuda CK, Block SD, Cooper Z, et al. Measuring critical deficits in shared decision making before elective surgery. Patient Educ Couns. 2014;94:328-333.
15. Stanley BM, Walters DJ, Maddern GJ. Informed consent: how much information is enough? Aust N Z J Surg. 1998;68:788-791.
16. Turner P, Williams C. Informed consent: patients listen and read, but what information do they retain? N Z Med J. 2002;115:U218.
17. Fagerlin A, Lakhani I, Lantz PM, et al. An informed decision? Breast cancer patients and their knowledge about treatment. Patient Educ Couns. 2006;64:303-312.
18. Kwok AC, Semel ME, Lipsitz SR, et al. The intensity and variation of surgical care at the end of life: a retrospective cohort study. Lancet. 2011;378:1408-1413.
19. Kelley AS, Gold HT, Roach KW, Fins JJ. Differential medical and surgical house staff involvement in end-of-life decisions: a retrospective chart review. J Pain Symptom Manage. 2006;32:110-117.
20. Pecanac KE, Kehler JM, Brasel KJ, et al. “It’s Big Surgery”: Preoperative expressions of risk, responsibility, and commitment to treatment after high-risk operations. Ann Surg. 2014;259(3):458-463.
21. Hadler RA, Neuman MD, Raper S, et al. Advance directives and operating: room for improvement? A & A Case Rep. 2016;6:204-207.
22. Hutul OA, Carpenter RO, Tarpley JL, et al. Missed opportunities: a descriptive assessment of teaching and attitudes regarding communication skills in a surgical residency. Curr Surg. 2006;63:401-409.
23. International Patient Decision Aid Standards (IPDAS) Collaboration. Available at http://www.ipdas.ohri.ca/. Accessed on October 21, 2016.
24. Vetter TR, Goeddel LA, Boudreaux AM, et al. The perioperative surgical home: how can it make the case so everyone wins? BMC Anesthesiology. 2013;13:6.
25. Vetter TR, Ivankova NV, Pittet JF. Patient satisfaction with anesthesia: Beauty is in the eye of the consumer. Anesthesiology. 2013;119:245-247.
26. Schmitz CC, Braman JP, Turner N, et al. Learning by (video) example: a randomized study of communication skills training for end-of-life and error disclosure family care conferences. Am J Surg. 2016;212:996-1004.
27. Sepucha KR, Fowler JF, Mulley AG. Policy support for patient-centered care: the need for measurable improvements in decision quality. Health Affairs (Millwood). 2004;Suppl Variation:VAR54-VAR62.
28. Donabedian A. Evaluating the quality of medical care. 1966. Milbank Quart. 2005;83: 691-729.
29. Vetter TR, Ivankova NV, Goeddel LA, et al. An analysis of methodologies that can be used to validate if a perioperative surgical home improves the patient-centeredness, evidence-based practice, quality, safety, and value of patient care. Anesthesiology. 2013;119:1261-1274.
30. Cleary P. Satisfaction may not suffice! A commentary on “A patient’s perspective”. Int J Technol Assess Health Care. 1998;14(1):35-37.
31. U.S. Department of Health and Human Services, Centers for Medicare and Medicaid Services. Patients’ Rights Condition of Participation. 42 CFR 482.13(b)(2).
32. U.S. Department of Health and Human Services, Centers for Medicare and Medicaid Services. Surgical Services Condition of Participation. 482.51(b)(2).
33. The Joint Commission. Informed consent: more than getting a signature. Quick Safety. 2016;21:1-3.
34. Elwyn G, Scholl I, Tietbohl C, et al. “Many miles to go …”: a systematic review of the implementation of patient decision support interventions into routine clinical practice. BMC Med Inform Decis Mak. 2013;13(suppl 2):S14.
35. Cooper Z, Corso K, Bernacki R, et al. Conversations about treatment preferences before highrisk surgery: a pilot study in the preoperative testing center. J Pall Med. 2014;16:701-707.
16.2 Fasting Guidelines
Shreya Aggarwal
Preoperative fasting guidelines have been established to facilitate safe and efficient anesthetic care. Our goal is to minimize the risk of perioperative aspiration while avoiding perioperative morbidity secondary to dehydration and hypoglycemia, limiting surgical delays and cancellations, and maintaining patient satisfaction and compliance. We define perioperative aspiration as aspiration of gastric contents during induction of anesthesia, intraoperatively, during emergence or immediately postoperatively during a time when laryngeal reflexes may not prevent the migration of gastric contents into the airway (1).
The nil per os (NPO) guidelines discussed below are limited to patients undergoing elective procedures with regional, MAC (sedation), or general anesthesia. They do not apply to patients undergoing procedures under local anesthesia without
concurrent sedation. The guidelines are not applicable to laboring women or patients undergoing emergency surgery (i.e., to prevent loss of limb or life). It is important to note that patients with an increased risk of aspiration (see Table 16.3) may require additional evaluation and modification of the anesthetic plan to prevent aspiration. Therefore, a thorough preoperative screening history and examination should be obtained for every patient anticipating anesthesia in order to identify these characteristics. The following ASA NPO guidelines apply to both pediatric and adult populations.
concurrent sedation. The guidelines are not applicable to laboring women or patients undergoing emergency surgery (i.e., to prevent loss of limb or life). It is important to note that patients with an increased risk of aspiration (see Table 16.3) may require additional evaluation and modification of the anesthetic plan to prevent aspiration. Therefore, a thorough preoperative screening history and examination should be obtained for every patient anticipating anesthesia in order to identify these characteristics. The following ASA NPO guidelines apply to both pediatric and adult populations.
It is appropriate to fast for 2 hours before anesthesia after the ingestion of clear liquids. Patients receiving breast milk should fast for 4 hours prior to the procedure. Infant formula, nonhuman milk, and nutritional supplement beverages require 6 hours of fasting. Of note, alcohol is not considered a “clear liquid” and also requires 6 hours of fasting. Solid foods consisting of a light meal require 6 hours of fasting, while foods higher in fat content require at least 8 hours of fasting. The type of liquid ingested is more significant than the volume of liquid ingested. However, when determining the gastric emptying time for solids, both the amount and type of food ingested must be considered (1). No fluid or solid should be ingested 2 hours prior to the procedure. An exception to this is the ingestion of oral medication. NPO guidelines do not apply to parental nutrition and this should be continued during the perioperative period. Enteral nutrition with tube feeds may be continued if administered via the postpyloric route. If the location of administration is not postpyloric, enteral supplementation should be discontinued 8 hours preoperatively (Table 16.2).
Pulmonary aspiration, although feared, is a relatively rare event. The incidence is approximately 1 in 3,000 cases of general anesthesia (2). The incidence is higher among cesarean sections, 1 in 500 (3), and is 1 in 895 for emergency surgery (2). Minimizing the risk of aspiration, however, has become a cornerstone of clinical anesthesia practice given the potential for aspiration pneumonitis, bronchospasm, laryngospasm, and respiratory complications. Patient characteristics that increase the volume of gastric contents, reduce esophageal motility, or delay gastric emptying increase the risk of aspiration (Table 16.3). Labor delays gastric emptying in the pregnant patient (4). Obesity increases the volume of gastric contents and decreases
gastric pH; however, obesity without any comorbidity has not been demonstrated in our current literature to consistently increase a patient’s risk for aspiration. It is important to note that obesity can be associated with other risk factors for aspiration, such as diabetes mellitus. In our current practice, morbid obesity (BMI >40) is considered a risk factor for aspiration. Patients at risk of aspiration who also have concurrent pulmonary disease predisposing them to worsened respiratory complications should be given special consideration during the preoperative evaluation process.
gastric pH; however, obesity without any comorbidity has not been demonstrated in our current literature to consistently increase a patient’s risk for aspiration. It is important to note that obesity can be associated with other risk factors for aspiration, such as diabetes mellitus. In our current practice, morbid obesity (BMI >40) is considered a risk factor for aspiration. Patients at risk of aspiration who also have concurrent pulmonary disease predisposing them to worsened respiratory complications should be given special consideration during the preoperative evaluation process.
TABLE 16.2 Fasting Guidelines | ||||||||||||||||||
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