Strategies in the high-risk cardiac patient undergoing non-cardiac surgery

Best Practice and Research: Clinical Anaesthesiology

Volumn 18, Issue 4, 2004, Pages 549-563

  Stevens, Robert D ^a   Fleisher, Lee A ^b  

^a JOHNS HOPKINS UNIVERSITY SCHOOL OF MEDICINE   (United States)

^b UNIVERSITY OF PENNSYLVANIA   (United States)

Author keywords

Myocardial stress testing; Perioperative cardiac complications; Pharmacological cardioprotection; Risk stratification

Indexed keywords

ACETYLSALICYLIC ACID; ALPHA 2 ADRENERGIC RECEPTOR STIMULATING AGENT; ATENOLOL; BETA ADRENERGIC RECEPTOR BLOCKING AGENT; CALCIUM CHANNEL BLOCKING AGENT; CLONIDINE; HYDROXYMETHYLGLUTARYL COENZYME A REDUCTASE INHIBITOR; MIVAZEROL;

ACCURACY; ANGIOCARDIOGRAPHY; ARTERY CATHETERIZATION; BRADYCARDIA; CLINICAL TRIAL; DRUG MECHANISM; EPIDURAL ANESTHESIA; EXERCISE TEST; HEART DEATH; HEART DISEASE; HEART INFARCTION; HEART MUSCLE ISCHEMIA; HEART MUSCLE REVASCULARIZATION; HEMODYNAMICS; HIGH RISK PATIENT; HUMAN; INCIDENCE; LUNG DISEASE; MORBIDITY; NON INVASIVE MEASUREMENT; PERCUTANEOUS CORONARY INTERVENTION; PERIOPERATIVE PERIOD; PREDICTION; PREOPERATIVE CARE; PRIORITY JOURNAL; PULMONARY ARTERY; REGIONAL ANESTHESIA; REVIEW; RISK ASSESSMENT; RISK REDUCTION; SURGICAL MORTALITY; SURGICAL RISK; TRANSESOPHAGEAL ECHOCARDIOGRAPHY;

EID: 4344672570     PISSN: 15216896     EISSN: None     Source Type: Journal    
DOI: 10.1016/j.bpa.2004.05.011     Document Type: Article

References (106)

1. Mangano D.T. Perioperative cardiac morbidity Anesthesiology 72 1990 153-184
2. Hertzer N.R. Beven E.G. Young J.R. et al. Coronary artery disease in peripheral vascular patients. A classification of 1000 coronary angiograms and results of surgical management Annals of Surgery 199 1984 223-233
3. Ashton C.M. Petersen N.J. Wray N.P. et al. The incidence of perioperative myocardial infaction in men undergoing noncardiac surgery Annals of Internal Medicine 118 1993 504-510
4. L'Italien G.J. Cambria R.P. Cutler B.S. et al. Comparative early and late cardiac morbidity among patients requiring different vascular surgery procedures Journal of Vascular Surgery 21 1995 935-944
5. McFalls E.O. Ward H.B. Santilli S. et al. The influence of perioperative myocardial infarction on long-term prognosis following elective vascular surgery Chest 113 1998 681-686
6. Fleisher L.A. Eagle K.A. Lowering cardiac risk in noncardiac surgery New England Journal of Medicine 345 2001 1677-1682
7. Eagle K.A. Brundage B.H. Chaitman B.R. Guidelines for perioperative cardiovascular evaluation for noncardiac surgery. Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines. Committee on Perioperative Cardiovascular Evaluation for Noncardiac Surgery Circulation 93 1996 1278-1317
8. Eagle K.A. Berger P.B. Calkins H. et al. American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Committee to Update the 1996 Guidelines on Perioperative Cardiovascular Evaluation for Noncardiac Surgery). ACC/AHA guideline update for perioperative cardiovascular evaluation for on cardiac surgery-executive summary a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Committee to Update the 1996 Guidelines on Perioperative Cardiovascular Evaluation for Noncardiac Surgery) Circulation 105 2002 1257-1267
9. American College of Physicians Guidelines for assessing and managing the perioperativ risk from coronary artery disease associated with major noncardiac surgery Annals of Internal Medicine 127 1997 309-312
10. Palda V.A. Detsky A.S. Perioperative assessment and management of risk from coronary artery disease Annals of Internal Medicine 127 1997 313-328
11. Ohman E.M. Armstrong P.W. Christenson R.H. et al. Cardiac troponin T levels for risk stratification in acute myocardial ischemia. GUSTO IIA investigators New England Journal of Medicine 335 1996 1333-1341
12. Alpert J.S. Thygesen K. Antman E. Bassand J.P. Myocardial infarction redefined - a consensus document of The Joint European Society of Cardiology/American College of Cardiology Committee for the redefinition of myocardial infarction Journal of the American College of Cardiologists 36 2000 959-969
13. French J.K. White H.D. Clinical implications of the new definition of myocardial infarction Heart 90 2004 99-106
14. Adams J.E.III Sicard G.A. Allen B.T. et al. Diagnosis of perioperative myocardial infarction with measurement of cardiac troponin I New England Journal of Medicine 330 1994 670-674
15. Kim L.J. Martinez E.A. Faraday N. et al. Cardiac troponin I predicts short-term mortality in vascular surgery patients Circulation 106 2002 2366-2371
16. Dripps R.D. Lamont A. Eckenhoff J.E. The role of anesthesia in surgical mortality JAMA 178 1961 261-266
17. Goldman L. Caldera D.L. Nussbaum S.R. et al. Multifactorial index of cardiac risk in noncardiac surgical procedures New England Journal of Medicine 297 1977 845-850
18. Detsky A. Abrams H. McLaughlin J. et al. Predicting cardiac complications in patients undergoing non-cardiac surgery Journal of General Internal Medicine 1 1986 211-219
19. Eagle K.A. Coley C.M. Newell J.B. et al. Combining clinical and thallium data optimizes preoperative assessment of cardiac risk before major vascular surgery Annals of Internal Medicine 110 1989 859-866
20. Lee T.H. Marcantonio E.R. Mangione C.M. et al. Derivation and prospective validation of a simple index for prediction of cardiac risk of major noncardiac surgery Circulation 100 1999 1043-1049
21. Gilbert K. Larocque B.J. Patrick L.T. Prospective evaluation of cardiac risk indices for patients undergoing noncardiac surgery Annals of Internal Medicine 133 2000 356-359
22. Grayburn P.A. Hillis L.D. Cardiac events in patients undergoing noncardiac surgery: Shifting the paradigm from noninvasive risk stratification to therapy Annals of Internal Medicine 138 2003 506-511
23. Baron J.F. Mundler O. Bertrand M. et al. Dipyridamole-thallium scintigraphy and gated radionuclide angiography to assess cardiac risk before abdominal aortic surgery New England Journal of Medicine 330 1994 663-669
24. Mangano D.T. London M.J. Tubau J.F. et al. Dipyridamole thallium-201 scintigraphy as a preoperative screening test. A reexamination of its predictive potential. Study of Perioperative Ischemia Research Group Circulation 84 1991 493-502
25. L'Italien G.J. Paul S.D. Hendel R.C. et al. Development and validation of a Bayesian model for perioperative cardiac risk assessment in a cohort of 1,081 vascular surgical candidates Journal of the American College of Cardiologists 27 1996 779-786
26. de Virgilio C. Wall D.B. Ephraim L. et al. An abnormal dipyridamole thallium/sestamibi fails to predict long-term cardiac events in vascular surgery patients Annals of Vascular Surgery 15 2001 267-271
27. de Virgilio C. Toosie K. Elbassir M. et al. Dipyridamole-thallium/sestamibi before vascular surgery: A prospective blinded study in moderate-risk patients Journal of Vascular Surgery 32 2000 77-89
28. Falcone R.A. Nass C. Jermyn R. et al. The value of preoperative pharmacologic stress testing before vascular surgery using ACC/AHA guidelines: A prospective, randomized trial Journal of Cardiothoracic and Vascular Anesthesia 17 2003 694-698
29. Mantha S. Roizen M.F. Barnard J. et al. Relative effectiveness of four preoperative tests for predicting adverse cardiac outcomes after vascular surgery: A meta-analysis Anesthesia and Analgesia 79 1994 422-433
30. Shaw L.J. Eagle K.A. Gersh B.J. Miller D.D. Meta-analysis of intravenous dipyridamole-thallium-201 imaging (1985 to 1994) and dobutamine echocardiography (1991 to 1994) for risk stratification before vascular surgery Journal of the American College of Cardiologists 27 1996 787-798
31. Etchells E. Meade M. Tomlinson G. Cook D. Semiquantitative dipyridamole myocardial stress perfusion imaging for cardiac risk assessment before noncardiac vascular surgery: A meta-analysis Journal of Vascular Surgery 36 2002 534-540
32. Kertai M.D. Boersma E. Bax J.J. et al. A meta-analysis comparing the prognostic accuracy of six diagnostic tests for predicting perioperative cardiac risk in patients undergoing major vascular surgery Heart 89 2003 1327-1334
33. Poldermans D. Boersma E. Bax J.J. et al. Correlation of location of acute myocardial infarct after noncardiac vascular surgery with preoperative dobutamine echocardiographic findings American Journal of Cardiology 88 2001 1413-1414
34. Boersma E. Poldermans D. Bax J.J. et al. DECREASE Study Group (Dutch Echocardiographic Cardiac Risk Evaluation Applying Stress Echocardiogrpahy). Predictors of cardiac events after major vascular surgery: Role of clinical characteristics, dobutamine echocardiography, and beta-blocker therapy JAMA 285 2001 1865-1873
35. Fleisher L.A. Eagle K.A. Shaffer T. Anderson G.F. Perioperative and long-term mortality rates after major vascular surgery: The relationship to preoperative testing in the medicare population Anesthesia and Analgesia 89 1999 849-855
36. Lustik S.J. Eichelberger J.P. Chibber A.K. Preoperative stress testing: New guidelines Journal of Clinical Anesthesia 14 2002 375-380
37. Mason J.J. Owens D.K. Harris R.A. et al. The role of coronary angiography and coronary revascularization before noncardiac vascular surgery JAMA 273 1995 1919-1925
38. Fleisher L.A. Skolnick E.D. Holroyd K.J. Lehmann H.P. Coronary artery revascularization before abdominal aortic aneurysm surgery: A decision analytic approach Anesthesia and Analgesia 79 1994 661-669
39. Back M.R. Schmacht D.C. Bowser A.N. et al. Critical appraisal of cardiac risk stratification before elective vascular surgery Vascular and Endovascular Surgery 37 2003 387-397
40. Licker M. Khatchatourian G. Schweizer A. et al. The impact of a cardioprotective protocol on the incidence of cardiac complications after aortic abdominal surgery Anesthesia and Analgesia 95 2002 1525-1533
41. Farid I. Litaker D. Tetzlaff J.E. Implementing ACC/AHA guidelines for the preoperative management of patients with coronary artery disease scheduled for noncardiac surgery: Effect on perioperative outcome Journal of Clinical Anesthesia 14 2002 126-128
42. Samain E. Farah E. Leseche G. Marty J. Guidelines for perioperative cardiac evaluation from the American College of Cardiology/American Heart Association task force are effective for stratifying cardiac risk before aortic surgery Journal of Vascular Surgery 31 2000 971-979
43. Bartels C. Bechtel J.F. Hossmann V. Horsch S. Cardiac risk stratification for high-risk vascular surgery Circulation 95 1997 2473-2475
44. Eagle K.A. Rihal C.S. Mickel M.C. et al. Cardiac risk of noncardiac surgery: Influence of coronary disease and type of surgery in 3368 operations. CASS Investigators and University of Michigan Heart Care Program. Coronary Artery Surgery Study Circulation 96 1997 1882-1887
45. Rihal C.S. Eagle K.A. Mickel M.C. et al. Surgical therapy for coronary artery disease among patients with combined coronary artery and peripheral vascular disease Circulation 91 1995 46-53
46. Massie M.T. Rohrer M.J. Leppo J.A. Cutler B.S. Is coronary angiography necessary for vascular surgery patients who have positive results of dipyridamole thallium scans? Journal of Vascular Surgery 25 1997 975-982
47. Landesberg G. Mosseri M. Wolf Y.G. et al. Preoperative thallium scanning, selective coronary revascularization, and long-term survival after major vascular surgery Circulation 108 2003 177-183
48. Hassan S.A. Hlatky M.A. Boothroyd D.B. et al. Outcomes of noncardiac surgery after coronary bypass surgery or coronary angioplasty in the Bypass Angioplasty Revascularization Investigation (BARI) American Journal of Medicine 110 2001 260-266
49. Allen J.R. Helling T.S. Hartzler G.O. Operative procedures not involving the heart after percutaneous transluminal coronary angioplasty Surgery, Gynecology and Obstetrics 173 1991 285-288
50. Elmore J.R. Hallett J.W. Jr. Gibbons R.J. et al. Myocardial revascularization before abdominal aortic aneurysmorrhaphy: Effect of coronary angioplasty Mayo Clinic Proceedings 68 1993 637-641
51. Gottlieb A. Banoub M. Sprung J. et al. Perioperative cardiovascular morbidity in patients with coronary artery disease undergoing vascular surgery after percutaneous transluminal coronary angioplasty Journal of Cardiothoracic and Vascular Anesthesia 12 1998 501-506
52. Posner K.L. Van Norman G.A. Chan V. Adverse cardiac outcomes after noncardiac surgery in patients with prior percutaneous transluminal coronary angioplasty Anesthesia and Analgesia 89 1999 553-560
53. Kaluza G.L. Joseph J. Lee J.R. et al. Catastrophic outcomes of noncardiac surgery soon after coronary stenting Journal of the American College of Cardiologists 35 2000 1288-1294
54. Wilson S.H. Fasseas P. Orford J.L. et al. Clinical outcome of patients undergoing non-cardiac surgery in the two months following coronary stenting Journal of the American College of Cardiologists 42 2003 234-240
55. McFalls E.O. Ward H.B. Krupski W.C. Prophylactic coronary artery revascularization for elective vascular surgery: Study designVeterans Affairs Cooperative Study Group on Coronary Artery Revascularization Prophylaxis for Elective Vascular Surgery Controlled Clinical Trials 20 1999 297-308
56. Warltier D.C. Pagel P.S. Kersten J.R. Approaches to the prevention of perioperative myocardial ischemia Anesthesiology 92 2000 253-259
57. Landesberg G. The pathophysiology of perioperative myocardial infarction: Facts and perspectives Journal of Cardiothoracic and Vascular Anesthesia 17 2003 90-100
58. London M.J. Zaugg M. Schaub M.C. Spahn D.R. Perioperative beta-adrenergic receptor blockade: Physiologic foundations and clinical controversies Anesthesiology 100 2004 170-175
59. Mangano D.T. Layug E.L. Wallace A. Tateo I. Effect of atenolol on mortality and cardiovascular morbidity after noncardiac surgery. Multicenter Study of Perioperative Ischemia Research Group New England Journal of Medicine 335 1996 1713-1720
60. Wallace A. Layug B. Tateo I. et al. Prophylactic atenolol reduces postoperative myocardial ischemia. McSPI Research Group Anesthesiology 88 1998 7-17
61. Poldermans D. Boersma E. Bax J.J. et al. The effect of bisoprolol on perioperative mortality and myocardial infarction in high-risk patients undergoing vascular surgery. Dutch Echocardiographic Cardiac Risk Evaluation Applying Stress Echocardiography Study Group New England Journal of Medicine 341 1999 1789-1794
62. Poldermans D. Boersma E. Bax J.J. et al. Dutch Echocardiographic Cardiac Risk Evaluation Applying Stress Echocardiography Study Group. Bisoprolol reduces cardiac death and myocardial infarction in high-risk patients as long as 2 years after successful major vascular surgery European Heart Journal 22 2001 1353-1358
63. Auerbach A.D. Goldman L. β-blockers and reduction of cardiac events in noncardiac surgery. Scientific review JAMA 287 2002 1435-1444
64. Stevens R.D. Burri H. Tramer M.R. Pharmacologic myocardial protection in patients undergoing noncardiac surgery: A quantitative systematic review Anesthesia and Analgesia 97 2003 623-633
65. Kamibayashi T. Maze M. Clinical uses of alpha2-adrenergic agonists Anesthesiology 93 2000 1345-1349
66. Ghignone M. Calvillo O. Quintin L. Anesthesia and hypertension: The effect of clonidine on perioperative hemodynamics and isoflurane requirements Anesthesiology 67 1987 3-10
67. Pluskwa F. Bonnet F. Saada M. et al. Effects of clonidine on variation of arterial blood pressure and heart rate during carotid artery surgery Journal of Cardiothoracic and Vascular Anesthesia 5 1991 431-436
68. Ellis J.E. Drijvers G. Pedlow S. et al. Premedication with oral and transdermal clonidine provides safe and efficacious postoperative sympatholysis Anesthesia and Analgesia 79 1994 1133-1140
69. Stühmeier K.D. Mainzer B. Cierpka J. et al. Small, oral dose of clonidine reduces the incidence of intraoperative myocardial ischemia in patients having vascular surgery Anesthesiology 85 1996 706-712
70. McSPI-Europe Research Group Perioperative sympatholysis: Beneficial effects of the alpha 2-adrenoceptor agonist mivazerol on hemodynamic stability and myocardial ischemia Anesthesiology 86 1997 346-363
71. Oliver M.F. Goldman L. Julian D.G. et al. Effect of mivazerol on perioperative cardiac complications during non-cardiac surgery in patients with coronary heart disease: The Eur Mivazerol Trial (EMIT) Anesthesiology 91 1999 951-961
72. Nishina K. Mikawa K. Uesugi T. et al. Efficacy of clonidine for prevention of perioperative myocardial ischemia: A critical appraisal and meta-analysis of the literature Anesthesiology 96 2002 323-329
73. Wijeysundera D.N. Naik J.S. Beattie W.S. Alpha-2 adrenergic agonists to prevent perioperative cardiovascular complications: A meta-analysis American Journal of Medicine 114 2003 742-752
74. Wijeysundera D.N. Beattie W.S. Calcium channel blockers for reducing cardiac morbidity after noncardiac surgery: A meta-analysis Anesthesia and Analgesia 97 2003 634-641
75. Vaughan C.J. Gotto A.M. Jr. Basson C.T. The evolving role of statins in the management of atherosclerosis Journal of the American College of Cardiologists 35 2000 1-10
76. Law M.R. Wald N.J. Rudnicka A.R. Quantifying effect of statins on low density lipoprotein cholesterol, ischaemic heart disease, and stroke: Systematic review and meta-analysis BMJ 326 2003 1423
77. Poldermans D. Bax J.J. Kertai M.D. et al. Statins are associated with a reduced incidence of perioperative mortality in patients undergoing major noncardiac vascular surgery Circulation 107 2003 1848-1851
78. Mangano D.T. Multicenter Study of Perioperative Ischemia Research Group. Aspirin and mortality from coronary bypass surgery New England Journal of Medicine 347 2002 1309-1317
79. Boysen G. Sorensen P.S. Juhler M.P. et al. Danish very-low-dose aspirin after carotid endarterectomy trial Stroke 19 1988 1211-1215
80. Lindblad B. Persson N.H. Takolander R. Bergqvist D. Does low-dose acetylsalicylic acid prevent stroke after carotid surgery? A double-blind, placebo-controlled randomized trial Stroke 24 1993 1125-1128
81. Taylor D.W. Barnett H.J. Haynes R.B. et al. Low-dose and high-dose acetylsalicylic acid for patients undergoing carotid endarterectomy: A randomised controlled trial. ASA and Carotid Endarterectomy (ACE) Trial Collaborators Lancet 353 1999 2179-2184
82. Scher K.S. Unplanned reoperation for bleeding American Surgeon 62 1996 52-55
83. Neilipovitz D.T. Bryson G.L. Nichol G. The effect of perioperative aspirin therapy in peripheral vascular surgery: A decision analysis Anesthesia and Analgesia 93 2001 573-580
84. Jackson M.R. Clagett G.P. Antithrombotic therapy in peripheral arterial occlusive disease Chest 119 supplement 1 2001 283S-299S
85. Peripheral Arterial Diseases Antiplatelet Consensus Group Antiplatelet therapy in peripheral arterial disease. Consensus statement European Journal of Vascular and Endovascular Surgery 26 2003 1-16
86. Wilson R.J. Woods I. Cardiovascular optimization for high-risk surgery Current Opinion in Critical Care 7 2001 195-199
87. Barone J.E. Tucker J.B. Rassias D. Corvo P.R. Routine perioperative pulmonary artery catheterization has no effect on rate of complications in vascular surgery: A meta-analysis American Surgeon 67 2001 674-679
88. Polanczyk C.A. Rohde L.E. Goldman L. et al. Right heart catheterization and cardiac complications in patients undergoing noncardiac surgery: an observational study JAMA 286 2001 309-314
89. Sandham J.D. Hull R.D. Brant R.F. et al. Canadian Critical Care Clinical Trials Group. A randomized, controlled trial of the use of pulmonary-artery catheters in high-risk surgical patients New England Journal of Medicine 348 2003 5-14
90. Collard C.D. Con: Intraoperative transesophageal echocardiography is not of utility in patients at high risk of adverse cardiac events undergoing noncardiac surgery Journal of Cardiothoracic and Vascular Anesthesia 18 2004 110-111
91. Suriani R.J. Neustein S. Shore-Lesserson L. Konstadt S. Intraoperative transesophageal echocardiography during noncardiac surgery Journal of Cardiothoracic and Vascular Anesthesia 12 1998 274-280
92. Denault A.Y. Couture P. McKenty S. et al. Perioperative use of transesophageal echocardiography by anesthesiologists: Impact in noncardiac surgery and in the intensive care unit Canadian Journal of Anaesthesia 49 2002 287-293
93. Hofer C.K. Zollinger A. Rak M. et al. Therapeutic impact of intra-operative transoesophageal echocardiography during noncardiac surgery Anaesthesia 59 2004 3-9
94. American Society of Anesthesiologists and the Society of Cardiovascular Anesthesiologists Task Force on Transesophageal Echocardiography Practice guidelines for perioperative transesophageal echocardiography Anesthesiology 84 1996 986-1006
95. Eisenberg M.J. London M.J. Leung J.M. et al. Monitoring for myocardial ischemia during noncardiac surgery. A technology assessment of transesophageal echocardiography and 12-lead electrocardiography. The Study of Perioperative Ischemia Research Group JAMA 268 1992 210-216
96. Fleisher L.A. Real-time intraoperative monitoring of myocardial ischemia in noncardiac surgery Anesthesiology 92 2000 1183-1188
97. Bode R.H. Jr. Lewis K.P. Zarich S.W. et al. Cardiac outcome after peripheral vascular surgery. Comparison of general and regional anesthesia Anesthesiology 84 1996 3-13
98. Garnett R.L. MacIntyre A. Lindsay P. et al. Perioperative ischaemia in aortic surgery: Combined epidural/general anaesthesia and epidural analgesia vs general anaesthesia and i.v. analgesia Canadian Journal Anaesthesia 43 1996 769-777
99. Norris E.J. Beattie C. Perler B.A. et al. Double-masked randomized trial comparing alternate combinations of intraoperative anesthesia and postoperative analgesia in abdominal aortic surgery Anesthesiology 95 2001 1054-1067
100. Park W.Y. Thompson J.S. Lee K.K. Effect of epidural anesthesia and analgesia on perioperative outcome: A randomized, controlled Veterans Affairs cooperative study Annals of Surgery 234 2001 560-569
101. Rigg J.R. Jamrozik K. Myles P.S. et al. MASTER Anaethesia Trial Study Group. Epidural anaesthesia and analgesia and outcome of major surgery: a randomized trial Lancet 359 2002 1276-1282
102. Rodgers A. Walker N. Schug S. et al. Reduction of postoperative mortality and morbidity with epidural or spinal anaesthesia: Results from overview of randomised trials BMJ 321 2000 1493
103. Scheinin H. Virtanen T. Kentala E. et al. Epidural infusion of bupivacaine and fentanyl reduces perioperative myocardial ischaemia in elderly patients with hip fracture: A randomized controlled trial Acta Anesthesiologica Scandinavica 44 2000 1061-1070
104. Matot I. Oppenheim-Eden A. Ratrot R. et al. Preoperative cardiac events in elderly patients with hip fracture randomized to epidural or conventional analgesia Anesthesiology 98 2003 156-163
105. Beattie W.S. Badner N.H. Choi P. Epidural analgesia reduces postoperative myocardial infarction: A meta-analysis Anesthesia and Analgesia 93 2001 853-858
106. Wu C.L. Anderson G.F. Herbert R. et al. Effect of postoperative epidural analgesia on morbidity and mortality after total hip replacement surgery in medicare patients Regional Anesthesia and Pain Medicine 28 2003 271-278