Guidelines for 2010

Educational Objectives

The purpose of this program is to improve management of anesthesia through adherence to guidelines and protocols for noncardiac surgery and perioperative care. After hearing and assimilating this program, the clinician will be better able to:

1.   Explain the purpose of the preoperative cardiac evaluation.

2.   Describe the concepts underlying the algorithm for preoperative cardiac evaluation published by the American Heart Association (AHA) and the American College of Cardiology (ACC).

3.   Recognize the importance of adequate communication between care teams in improving practice protocols and optimizing outcomes.

4.   Discuss some of the current controversies in perioperative care

5.   List the essential objectives of surgical safety and components of a surgical checklist.

Faculty Disclosure

In adherence to ACCME Standards for Commercial Support, Audio-Digest requires all faculty and members of the planning committee to disclose relevant financial relationships within the past 12 months that might create any personal conflicts of in­terest. Any identified conflicts were resolved to ensure that this educational activity promotes quality in health care and not a proprietary business or commercial interest. For this program, the faculty and planning committee reported nothing to disclose.

Acknowledgements

Dr. Galway spoke at Comprehensive Anesthesiology Review, held March 28 to April 2, 2009, in Cleveland, OH, and sponsored by the Cleveland Clinic Foundation. Dr. Lumb spoke at California Society of Anesthesiologists Annual Meeting and Clinical Anes­thesia Update, held May 15-17, 2009, in Monterey, CA, and sponsored by the California Society of Anesthesiologists. The Au­dio-Digest Foundation thanks the speakers and the sponsors for their cooperation in the production of this program.

AHA/ACC Guidelines for Preoperative Cardiac Evaluation for Noncardiac Surgery

Ursula Galway, MD, Staff Anesthesiologist, Cleveland Clinic, Cleveland, OH

Background: »27 million anesthetics administered annually, of which »8 million administered to patients with known coronary artery disease (CAD) or cardiac risk factors; »50,000 patients experience perioperative myocardial infarction (MI); »1 million experience perioperative cardiac complication; associated annual costs »$20 billion; »6 million noncardiac surgeries performed annually on patients >65 yr of age; mortality associated with MI without surgery »20%; incidence of perioperative MI without history of previous MI »0.6%; with history of MI, incidence »60%; associated mortality 30% to 70%

Preoperative cardiac evaluation: purpose  —  to clarify patient’s current medical status (not clearance); assess car­diac risk profile, direct perioperative and postoperative care, and manage patient’s current cardiac disease; Ameri­can Society of Anesthesiologists (ASA) physical status predicts morbidity and mortality, but does not identify patients needing more preoperative testing; type of surgical procedure influences risk for adverse perioperative out­comes

American Heart Association (AHA)/American College of Cardiology (ACC) guidelines: algorithm to assist in clinical decision-making for cardiac evaluation; updated in 2007

Underlying concepts: intervention rarely necessary unless indicated irrespective of preoperative context; preopera­tive tests recommended only if information will lead to change in surgical procedure, medical therapy, monitor­ing, or postponement of surgery until cardiac condition corrected or stabilized; coronary revascularization before noncardiac surgery appropriate only for small subset of high-risk patients; risk associated with coronary inter­vention or cardiac surgery may approach or exceed risk associated with proposed noncardiac surgery

Need for surgery: emergency  —  base perioperative management on patient’s cardiac status, history, medications, and available test results; urgent or elective  —  further evaluation determined by scheduling of surgery, patient’s cardiac history, and presence of risk factors

Cardiovascular risk factors: active (unstable) cardiac conditions  —  more serious; require presurgical assessment; unstable angina; acute MI (within 7 days); recent MI (within 7-30 days); decompensated congestive heart failure (CHF; includes worsening heart failure with worsening symptoms, or new-onset heart failure); significant ar­rhythmia (high-degree atrioventricular blocks, supraventricular tachycardia with uncontrolled ventricular rate >100 beats per minute, symptomatic ventricular arrhythmia, bradycardia, or new ventricular tachycardia); severe valvular disease (aortic stenosis with valve area <1 cm² or new aortic valve gradient >40 mm Hg, or symptomatic mitral stenosis); these conditions mandate further management and investigation (delay of surgery possible)

Clinical risk factors: replaced intermediate risk factors in original algorithm; 1) history of ischemic heart disease (MI >1 mo ago, or history of positive stress test or ischemic symptoms); 2) CHF (history of edema, dyspnea, rales, S₃, or signs of heart failure on chest x-ray); 3) cerebrovascular disease (history of stroke or transient isch­emic attack); 4) diabetes; 5) renal insufficiency  

Surgical risk: high  —  open vascular procedures (cardiac risk >5%); intermediate  —  cardiac risk 1% to 5%; includes most surgeries (eg, orthopedic, prostate, head-and-neck, carotid endarterectomy); low  —  cardiac risk <1%; in­cludes superficial and ambulatory procedures (eg, biopsies)

Functional capacity: ability to perform common daily tasks; measured in metabolic equivalents (METs; 1 MET av­erage O₂ consumption of 40-yr-old, 70-kg man; 4 METs indicates ability to climb hill or flight of stairs); excellent  —  >10 METs; poor  —  <4 METs; suggests increased risk for perioperative cardiac complications

Algorithm for steps addressed in guideline: emergency surgery?  —  if yes, no time for cardiac assessment; provide perioperative medical management and surveillance to extent possible; active cardiac condition(s)?  —   if yes and surgery not emergency, delay surgery until cardiac problem clarified and treated; if surgery necessary soon, bal­loon angioplasty may be best intervention (surgery may proceed after 2-4 wk of antiplatelet therapy); if surgery can wait 4 to 6 wk, can place bare metal stent; if surgery can wait 12 mo, place drug-eluting stent (requires 12 mo of dual antiplatelet therapy); low-risk surgery?  —  if yes, and no active cardiac condition, proceed with no further work-up; functional capacity?  —consider with higher-risk procedures; proceed with no further work-up if >4 METs; if <4 METs, determine number of clinical risk factors; proceed with surgery if none present; further car­diac testing indicated if patient has ³3 risk factors; if patient has 1 or 2 risk factors, consider testing if it will af­fect management, or proceed to surgery with heart-rate control; intermediate-risk surgery, functional capacity <4 METs  —  proceed with surgery if no clinical risk factors; if >1 risk factor, consider cardiac testing if it will change management, or proceed to surgery with heart-rate control

Recommendations for b-blockers: class I  —  if patient currently taking, continue; recommended if patient undergo­ing vascular surgery and at high cardiac risk due to findings of ischemia; class IIA  —  consider for patients under­going vascular surgery with heart disease identified on preoperative assessment, those who have >1 clinical risk factor, or if patient has heart disease and requires intermediate-risk surgery

Indications for presurgical electrocardiography (ECG): vascular surgery; known coronary artery, peripheral vascu­lar, or cerebrovascular disease and intermediate-risk surgery, or symptoms of ischemia; consider for patients with 1 risk factor scheduled for intermediate-risk surgery

Indications for presurgical stress test: presence of active cardiac condition; patients with ³3 clinical risk factors and functional capacity <4 METs scheduled for vascular surgery

Indications for echocardiography: exertional dyspnea or worsening heart failure

New Perioperative Guidelines

Philip D. Lumb, MB, BS, Professor and Chair, Department of Anesthesiology, Keck School of Medicine, Uni­versity of Southern California, Los Angeles

Importance of protocols: confer ability to question process and produce answers

Quality improvement: results from frank discussion of outcome information among all surgical team members; op­portunity to change care to improve outcomes; Surviving Sepsis campaign provides controlled forum for appro­priate evaluation of effects of changes in practice and practice standards on outcomes; true quality improvements require that discussions take place in “safe harbor” (legally protected environment)

Improved management of in-hospital code: equivocal despite implementation of specialized teams; due in part to “conflicting personalities” (desire of some staff members to take charge without assuming responsibility for out­come)

Practice protocols: standard (for, eg, blood pressure above which surgery must be delayed) may be based on clinical opinion rather than formal evidence; accrual of sufficient number of cases to build database requires environment of professionalism, trust, and willingness to explore outcomes in safe harbor

Surviving Sepsis campaign: website http://www.survivingsepsis.com; guides practice in many emergency depart­ments; began in Detroit as study of optimization of outcomes among infected emergency patients; included first investigation of relationship between central venous oxygen saturation and resuscitation; among first studies of benefits of tight glycemic control; currently tests new antibiotics, effects of aggressive fluid resuscitation, and he­modynamic and ventilatory support

Remaining controversies: hemodynamics  —  no agreement on superiority of crystalloid vs colloid; hematocrit level should be appropriate (»30%); blood clotting should be adequate (administer clotting factors if necessary); albu­min concentration should be >3 mg/dL; aggressive fluid resuscitation  —  blood pressure not “the end-all and the be-all;” for 70-kg person in septic shock, 60 mg/kg equals 5 L fluid administered within first hour; considered very aggressive (not performed at most institutions); may be necessary if resuscitating patient toward central ve­nous oxygen saturation of 65%; hemodynamic support  —  for managing hypotension, most anesthesiologists more familiar with phenylephrine (eg, Neosynephrine) than dopamine; earlier use of vasopressors  — recent con­troversial change; norepinephrine recommended; vasopressin for refractory hypotension

Mechanical ventilation: large tidal volume ventilation often used during surgery; data from Acute Respiratory Dis­tress Syndrome Network (ARDSNet) suggest prolonged large tidal volume ventilation in critical care units asso­ciated with poor outcomes; does enhance patient comfort during mechanical ventilation; discomfort associated with mechanical ventilation due largely to increased firing of J receptors when functional residual capacity re­duced; consider possibility that 10 to 12 mL/kg routinely administered during surgery may increase risk for barotrauma; caveat  —  ARDSNet data do not include compliance-corrected ventilator tubing (delivered tidal volume not necessarily known); difficulties arise when compliance-corrected tubing used in intensive care unit (ICU), but not operating room; important point for discussion when transferring patient to ICU after surgery; recommendations  —  avoid high tidal volumes whenever possible, and use positive end expiratory pressure (PEEP) to modify inspired oxygen concentration; elevating head of bed to 45^o decreases risk for ventilator-asso­ciated pneumonia (should be recommended by anesthesiologist); bicarbonate  —  Surviving Sepsis guideline does not recommend for lactic acidemia with pH ³7.15, despite common use at higher pH levels by many anesthesiol­ogists; transfer protocols  —  should have protocols for analgesia and sedation and discuss these with ICU person­nel; consider using sedation scoring index (eg, Ramsay Sedation Scale); need means of indicating to ICU staff level of patient’s neuromuscular blockade and timing of next dose

Tight glycemic control: less popular today than 3 yr ago (associated with higher mortality rate in outpatient study of ambulatory diabetics); practice of tight control began after 2001 study demonstrated benefits after cardiac sur­gery; findings never reproduced, yet became standard practice, even for patients in whom hypoglycemia strongly contraindicated

World Health Organization (WHO) Safe Surgery campaign: defined major surgery as any procedure involving incision, excision, manipulation, or suturing of tissue which requires regional or general anesthesia or sedation; complications after inpatient surgery occur in ³25% of patients; reported crude mortality rate after major surgery 0.5% to 5.0%; at least half of adverse events related to surgical care preventable; known principles of surgical safety (eg, sterile technique) applied inconsistently

WHO working groups: Surgical Site Infection Prevention; Safe Anesthesia; Safe Surgical Teams (to reduce operat­ing room stress); Measurement of Surgical Services (compares international patterns of surgical safety for hospi­tal and public health officials; defines minimum set of uniform measures for international surveillance of surgical care; checklists critical for monitoring safe surgical practices)

Essential objectives of surgical safety: operate on correct patient at correct site; use known harm-prevention meth­ods while patient anesthetized; prepare for life-threatening loss of airway, diminished respiratory function, or blood loss; avoid inducing adverse or allergic reactions; minimize risk for surgical site infection or retention of sponges or instruments in surgical site (may occur even when count correct, especially with complex procedures involving trauma or multiple surgical teams); most important  —effectively communicate information critical for safe conduct of operation; in speaker’s opinion, professionalism has broken down to greatest extent in this area

Checklist requirements: simplicity, applicability, and measurability

Components: sign-in  —  confirm patient identity, surgical site, operating room, and consent; complete anesthesia safety check; start pulse oximetry; confirm all resources available, including all team members and required imaging; administer antibiotic prophylaxis; surgical time-out  —  before incision; all personnel introduced and roles defined; general discussion of case; sign-out  —patient transfer to next level of care; anesthesiologists must spend sufficient time and be consistent with best patient care; define key concerns for recovery and post­operative management; controversies include whether to use situation-background-assessment-recommenda­tion (SBAR) technique or patient transfer protocols under development; communication and trust critical; postoperative transfer requires moving from inter-vention to maintenance, from control to independence, from pharmacologic compromise to pharmacologic withdrawal, and from pain management to stress re-duction; ef­fective patient transfer requires clear understanding of different care environments and good communication between different care teams

TranSafe: safe transfer protocol developed at USC; components  —  discuss anesthetic and treatment plan with nurses; have respiratory and airway management plan in place; postoperative analgesia management and stress reduction plan; nutrition plan; systems review; antibiotics; fluid management; and emesis control

Conclusion: quality improvement requires sharing information about outcomes among all members of surgical and ICU teams in environment that facilitates development of improved patient care protocols

Suggested Reading

Dellinger RP et al: Surviving Sepsis Campaign: international guidelines for management of severe sepsis and septic shock: 2008. Crit Care Med 36:296. 2008; Dellinger RP, Vincent JL: The Surviving Sepsis Campaign change bundles and clinical practice. Crit Care 9:653, 2005; Devereaux PJ et al: Effects of extended-release metoprolol succinate in patients undergoing non-cardiac surgery (POISE trial): a randomised controlled trial. Lancet 371:1839, 2008; Fleisher LA et al: ACC/AHA 2007 Guidelines on Perioperative Cardiovascular Evaluation and Care for Noncardiac Surgery: Executive Summary. Anesth Analg 106:685, 2008; Goldman SM et al: Outcome improvement and cost reduction in an increasingly morbid cardiac surgery population. Semin Car­diothorac Vasc Anesth 10:171, 2006; Gunn SR et al: Equipment review: the success of early goal-directed therapy for septic shock prompts evaluation of current approaches for monitoring the adequacy of resuscitation. Crit Care 9:349, 2005; Shanawani H: Lessons from the ARDS network ventilator trial design controversy. Respir Care Clin N Am 10:317, 2004; Shorr AF et al: Economic implications of an evidence-based sepsis protocol: can we improve outcomes and lower costs? Crit Care Med 35:1257, 2007; Sihler KC, Nathens AB: Management of severe sepsis in the surgical patient. Surg Clin North Am 86:1457, 2006; Van den Berghe G et al: Intensive insulin therapy in critically ill patients. N Engl J Med 345:1359, 2001; Vender JS et al: Sedation, anal­gesia, and neuromuscular blockade in sepsis: an evidence-based review. Crit Care Med 32:S554, 2004.