University of North Dakota Nurse Anesthesia Specialization Student Presentations

1. University of North Dakota Nurse Anesthesia Specialization Student Presentations

2. Spinal Hematoma Formation Following Neuraxial Anesthesia in the Anticoagulated Patient Lisa Bell, SRNA University of North Dakota

3. Introduction • The formation of a spinal hematoma is strongly correlated with the use of anticoagulation medications. • Incidence of epidural hematoma formation is 1:150,000. • Ratio of hematoma formation decreases slightly with spinal blocks, with a reported incidence of 1:220,000. • The number of patients on medications that alter clotting status continues to increase. • When patients present with altered coagulation, anesthesia providers are challenged with deciding which regional anesthetic procedures can be safely performed. • (Tyagi & Bhattacharya, 2002)

4. Problem Available guidelines that focus on anticoagulation and the performance of regional anesthesia vary from source to source. Therefore, nurse anesthetists are required to make decisions based on their best judgment, rather than a consistent guideline, in attempt to ensure patient safety.

5. Purpose The purpose of this project was to explore the association between neuraxial anesthesia, anticoagulation therapy, and spinal hematoma formation. Anticoagulation guidelines were reviewed to determine when regional anesthesia could be safely performed based on available laboratory data. The appropriate timing of spinal or epidural needle placement and catheter removal relative to the timing of anticoagulant drug administration was also examined.

6. Significance This project was aimed at compiling the diverse recommendations that are available to serve as a reference for anesthesia providers in attempt to prevent the formation of a spinal hematoma. The recommendations were condensed into a small pocket guide to remind anesthetists of the factors that need to be considered prior to the performance of a regional technique in an anticoagulated patient.

7. Methods A comprehensive literature review that included: available guidelines, retrospective reviews, case reports, and prospective studies was conducted. The findings were compiled and presented in a power point format which displayed the association between spinal hematoma formation and anticoagulation therapy. The physiologic framework of adaptation and homeostasis was used as the theoretical basis for the project.

8. Unfractionated Heparin When heparin is administered IV, the activated partial thromboplastin time (aPTT) is utilized to monitor its anticoagulant effect. The normal range for an aPTT is 20-35 seconds in an adult. (Kee, 1999) When patients are receiving subcutaneous (SQ) heparin in doses of 5000 Units or less, the aPTT is not usually monitored. (Tyagi & Bhattacharya, 2002) Needle insertion and catheter removal can occur at any time following SQ administration of heparin in doses less than 5000 Units. (UWMC, 2006) In doses greater than 5000 Units, and when heparin is administered IV, needle placement should not occur unless the aPTT is less than 40 seconds. Under these same circumstances, the administration of heparin should be avoided when an indwelling catheter is in place. (UWMC, 2006)

9. Unfractionated Heparin (cont.) If a regional anesthetic technique is planned on a patient that is receiving anticoagulation, the administration of heparin should not occur for one hour following the placement of the needle. Indwelling catheters should not be discontinued for 2-4 hours after the last administered heparin dose. When heparin is administered with other anticoagulant medications, there may be an increased risk of spinal hematoma formation. A platelet count should be drawn prior to needle insertion or catheter removal on patients that have received heparin for greater than four days. (Horlocker et al., 2003)

10. Low Molecular Weight Heparin (LMWH) The response of LMWH is very predictable, which eliminates the requirement for aPTT monitoring. A normal dose of enoxaparin is 40 mg SQ daily or 30 mg SQ twice daily. Needle placement and indwelling catheter removal should be delayed for at least 10-12 hours following a normal dose of LMWH. Higher than normal doses of LMWH include amounts of 1 mg/kg twice daily or 1.5 mg/kg daily. The administration of neuraxial anesthesia to patients on higher than normal doses of LMWH should be delayed for at least 24 hours. (Horlocker et al., 2003)

11. LMWH (cont.) If single daily dosing is planned, the first dose of LMWH can be administered approximately 6-8 hours postoperatively. However, the second postoperative dose should not occur prior to 24 hours of the first dose. When continuous epidural anesthesia is planned, the catheter can be left in place overnight and removed the next day. The anesthesia provider should wait approximately two or more hours before administering LMWH to a patient that has just had the indwelling catheter removed. (Horlocker et al., 2003)

12. Antiplatelet Agents Platelet function must be normal before regional anesthetic techniques are performed. A normal platelet count generally ranges from 150,000 to 400,000 mm3 in an adult. (Kee, 1999) The effect of aspirin therapy lasts the entire lifetime of the platelet, which is generally 8-10 days. (Katzung, 2004) Other nonsteroidal anti-inflammatory agents (NSAIDs) also alter platelet aggregation, however, normal platelet function is resumed approximately 1-3 days after the NSAIDs are discontinued. (Katzung, 2004) The use of NSAID therapy does not increase the risk of spinal hematoma formation following neuraxial anesthesia. (Horlocker et al., 2003)

13. Antiplatelet Agents (cont.) Clopidogrel and ticlopidine administration irreversibly inhibits platelet function. (Katzung, 2004) Ticlopidine should be discontinued 14 days prior to receiving neuraxial anesthesia and clopidogrel should be discontinued seven days prior to the scheduled regional procedure. (Horlocker et al., 2003) The risk of spinal hematoma formation following thienopyridine administration is unknown. (Horlocker et al., 2003)

14. Warfarin Prothrombin time (PT) and international normalized ratio (INR) are utilized to monitor the anticoagulant effect of warfarin therapy. A normal PT generally ranges from 10-13 seconds in an adult. (Kee, 1999) The INR is an international standardized test for PT that should only be used after the patient has been stabilized on warfarin. (Kee, 1999) Central neuraxial procedures should be delayed until the INR is within the range of 1.0-1.3. (Horlocker et al., 2003)

15. Warfarin (cont.) Warfarin administration must be stopped 4-5 days before a regional procedure is performed. If a dose of warfarin is administered before a scheduled surgery, a PT and INR level need to be checked prior to the regional technique. The PT and INR also need to be assessed prior to discontinuing an indwelling catheter on a patient that has received low doses of warfarin, 5 mg or less, throughout continuous epidural therapy. The catheter should not be removed until the INR is less than 1.5. Concurrent use of anticoagulation medications may increase the risk of spinal hematoma formation without affecting the PT or INR. (Horlocker et al., 2003)

16. Summary In attempt to reduce the occurrence of spinal hematoma formation, anesthesia providers need to be aware of all the risk factors, in addition to anticoagulant medications, that may contribute to this undesirable complication. This may be achieved by conducting a more complete assessment of the patient’s physical presentation, medical history, laboratory data, and current medication history prior to the administration of regional anesthesia.

17. References Horlocker, T.T., Benzon, H.T., Brown, D.L., Enneking, F.K., Heit, J.A., Mulroy, M.F. et al. (2003). Regional anesthesia in the anticoagulated patient: Defining the risks. Retrieved April 15, 2007, from http://www.asra.com/Consensus_Conferences Katzung, B.G. (2004). Basic and clinical pharmacology (9th ed.). New York: McGraw-Hill Companies. Kee, J.L. (1999). Laboratory diagnostic tests with nursing implications (5th ed.). Stamford, CT: Appleton & Lange. Tyagi, A., & Bhattacharya, A. (2002). Central neuraxial blocks and anticoagulation: A review of current trends. European Journal of Anesthesiology, 19, 317-329. University of Washington Medical Center. (2006). Anticoagulation guidelines for neuraxial procedures: Guidelines to prevent spinal hematoma following epidural/intrathecal/spinal procedures. Retrieved April 15, 2007 from http://www.uwmcacc.org/pdf/neuraxial.pdf

18. Perioperative Myocardial Infarction Lorrissa Bohlman, SRNA University of North Dakota

19. Introduction • Today, many patients who undergo surgery are older with more chronic comorbid medical illnesses. • Complications are common in this population and cardiac complications, including perioperative myocardial infarction, remain the leading cause of perioperative morbidity and mortality.

20. Purpose • The purpose of this project is to examine the perioperative identification and management of surgical patients at risk for perioperative myocardial infarction.

21. Review of Physiology: Myocardial Oxygen Balance • Coronary perfusion pressure is determined by the difference in the arterial end-diastolic pressure and the left ventricular end-diastolic pressure. • Decreases in aortic pressure or increases in ventricular pressure severely compromise coronary perfusion. • Myocardial oxygen demand is directly proportionate to myocardial blood flow. Any increase in demand must be met by an increase in blood flow.

22. Supply Heart rate Coronary perfusion pressure Arterial oxygen content Hemoglobin Coronary vessel diameter Demand Basal requirements Heart rate SBP Preload Contractility Factors that Affect Myocardial Oxygen Supply and Demand

23. Determinants of CO and BP • B.P. = C.O. x T.P.R • C.O. = S.V. x H.R • BP = Blood Pressure • HR = Heart Rate • TPR = Total Peripheral Resistance • CO = Cardiac Output

24. Surgical Triggers of Myocardial Infarction • This type of ischemia is characterized by ST segment depression and is usually proceeded by an increase in heart rate.

25. Preoperative History • Active Cardiac Conditions for Which the Patient Should Undergo Evaluation and Treatment Before Noncardiac Surgery (Identified by ACC & AHA) • Condition Examples: • Unstable coronary syndromes • Unstable or severe angina* (CCS class III or IV) Recent MI Decompensated HF (NYHA functional class IV; worsening or new-onset HF) • Significant arrhythmias: High-grade atrioventricular block, Mobitz II atrioventricular block, Third-degree atrioventricular heart block, Symptomatic ventricular arrhythmias, Supraventricular arrhythmias (including atrial fibrillation) with uncontrolled ventricular rate (HR greater than 100 bpm at rest) • Symptomatic bradycardia • Newly recognized ventricular tachycardia • Severe valvular disease • Severe aortic stenosis (mean pressure gradient greater than 40 mm Hg, aortic valve area less than 1.0 cm2, or symptomatic) • Symptomatic mitral stenosis (progressive dyspnea on exertion, exertional presyncope, or HF)

26. Functional capacity, exercise tolerance, is expressed using metabolic equivalent treadmill study levels (METs). Functional capacity is classified according to the level of daily activity the patient can tolerate. A study of 600 patients found perioperative myocardial infarction was increased in patients unable to meet a 4 MET demand. Noncardiac functional limitations (back/joint pain) may falsely elevate cardiac risk. 1 MET Can you take care of yourself? Walk indoors around the house? 4 METs Climb a flight of stairs or walk up a hill? Scrub the floor or move furniture? Golf? Bowel? Dance? 10 METs Swimming? Tennis? Basketball? Preoperative History: Functional Capacity

27. Clinical Assessment • The American College of Cardiology (ACC) and American Heart Association (AHA) group clinical predicators associated with increased perioperative cardiovascular risk into three main groups: • Major clinical predictors: The presence of 1 or more of these conditions mandates intensive management and may result in delay or cancellation of surgery unless the surgery is emergent: unstable or severe angina, significant arrhythmias, and severe valvular disease. • Intermediate: ischemic heart disease, compensated or prior heart failure, cerebrovascular disease, diabetes mellitus and renal insufficiency, history of MI, abnormal Q waves by ECG. • Minor: (markers for cardiovascular disease that have not been proved to increase perioperative risk independently) advanced age (greater than 70), abnormal ECG (LV hypertrophy, LBBB, ST-T abnormalities), rhythm other than sinus and uncontrolled systemic hypertension.

28. Surgery Specific Risk • The ACC and AHA guidelines grade the surgery specific risks as high (cardiac risk greater than 5%), intermediate (less than 5%), and low (less than 1%). • High: emergent major operations particularly in the elderly, aortic and other major vascular surgery, peripheral vascular surgery, and anticipated prolonged surgical procedures associated with large fluid shifts and/or blood loss. • Intermediate: carotid endarterectomy, head and neck surgery, intraperitoneal and intrathoracic surgery, orthopedic surgery, and prostate surgery. • Low: endoscopic procedures, superficial procedures, cataract surgery and breast surgery.

29. Framework for Determining which Patients are Candidates for Further Cardiac Testing Fleisher, L. A. et al. Circulation 2007;116:e418-e499

30. Proposed approach to the management of patients withprevious percutaneous coronary intervention (PCI) who require noncardiac surgery Fleisher, L. A. et al. Circulation 2007;116:e418-e499

31. Beta-Blockade • Current studies suggest that beta blockers reduce perioperative ischemia and may reduce the risk of MI and death in high-risk patients. • The dose should be titrated to achieve a resting heart rate of 60 beats per min (bpm) to increase the benefit of beta blockade. • Rate control with beta blockers should continue during the intraoperative and postoperative period to maintain a heart rate of 60 to 65 bpm.

32. Intraoperative Technique and Agent • There is no “ideal” agent or technique • All anesthetic agents have some degree of effect on the cardiovascular system • The choice of anesthetic technique and intraoperative monitors is left to the discretion of the anesthesia care team • Recognition of the perioperative plan is helpful in guiding intraoperative decisions • Remember to consider: • Postoperative monitoring, ventilation, analgesia • Use of antiplatelet agents or anticoagulants

33. Myocardial Infarction: Management • Despite the classification of myocardial infarction management is dictated by the patient’s hemodynamic status • Treatment of a hemodynamically stable patient should incorporate beta-blockers and intravenous nitroglycerine • Treatment of a hemodynamically unstable patient should focus on supporting circulation with positive inotropes and intra-aortic balloon pump • Involve a cardiac expert in management immediately

34. Myocardial Infarction: Management • While fibrinolytic therapy reduces mortality a substantial risk of surgical site bleeding exists • Time to reperfusion is critical in outcome • Patients with acute coronary occlusion benefit from angiography and revascularization within 12 hours • These reperfusion procedures should not be performed unless acute coronary occlusion is the suspected cause • Example: Hypertension and tachycardia increasing myocardial demand • Treatment: Lowering the heart rate and blood pressure provides increased benefit and decreased risk

35. Postoperative Period • Goals during the postoperative period do not differ significantly from the preoperative and intraoperative period • Prevention of ischemia • Adequate pain management • Pain can lead to increased myocardial oxygen demands • Continue supplemental oxygen • Early detection of myocardial ischemia or infarction • Prompt treatment as dictated by the patient’s level of hemodynamic stability

36. References • Adesanya, A.O., de Lemos, J.A., Greillich, N.B., & Whitten, C.W. (2006). Management of perioperative myocardial infarction in noncardiac surgical patients. Chest, 130(2), 1-21. • Agency for Health Care Research Quality. (2001).Beta blockers and reduction of perioperative cardiac exerts. In: AHRQ Publication No. 91-EO58, Rockville, MD: Retrieved March 15, 2007, from http://www.ahrq.gov/clinic/ptsaftey/chap25.htm • Akhtar, S. (2006). Ischemic heart disease. Anesthesiology Clinic, 24, 461-485. • American College of Cardiology. (2002). Guideline Update on Perioperative Cardiovascular Evaluation for Noncardiac Surgery (Committee to Update the 1996 Guidelines on Perioperative Cardiovascular Evaluation for Noncardiac Surgery). Retrieved February 1, 2007, from http://www.acc.org/clinical/guidelines/perio/dirIndex.htm • American College of Cardiology. (2006). Guideline Update on Perioperative Cardiovascular Evaluation for Noncardiac Surgery: Focused Update on Perioperative Beta-Blocker Therapy (Committee to Update the 2002 Guidelines on Perioperative Cardiovascular Evaluation for Noncardiac Surgery). Retrieved February 1, 2007, from http://content.onlinejacc.org/cgi/content/full/47/11/2343

37. References • American Society of Anesthesiologists. (2005). Standards for basic anesthetic monitoring. Amended: October 25, 2005; Approved: House of Delegates October 21, 1986. Retrieved February 15, from http://www.asahq.org/publicationsAndServices/standards/09.htm • Ashton, C.M., Petersen, N.J., Wray, N.P., Kiefe, C.I., Dunn, J.K., Wu, L., et al. (1993). The incidence of perioperative myocardial infarction in men undergoing noncardiac surgery. Annals of Internal Medicine, 118(7), 504-510. • Badner, N.H., Knill, R.L., Brown, J.E., Novick, T.V., & Gleb, A.W. (1998). Myocardial infarction after noncardiac surgery. Anesthesiology, 88(3) 572-578. • Baxter, A. & Kanji, S. (2007). Protocol implementation in anesthesia: Beta-blockade in non-cardiac surgery patients. Canadian Journal of Anesthesia, 54(2), 114-123. • Boersma, E., Poldermans, D., Bax, J.J., Steyerberg, E.W., Thompson, I.R., Banga, J.D.,et al. (2001). Predictors of cardiac events after major vascular surgery: Role of clinical characteristics, dobutamine echocardiography, and B-blocker therapy. Journal of the American Medical Association, 285(14), 1865-1873. • Bois, S., Couture, P., Boudreault, D., Lacombe., Fugere, F., Girard, F., et al. (1997). Epidural analgesia and intravenous patient-controlled analgesia result in similar rates of postoperative myocardial ischemia after aortic surgery. Anesthesia and Analgesia, 85(6), 1233-1239.

38. References • Breen, P., Lee, J., Pomposelli, F., Park, K.W. (2004). Timing of high-risk vascular surgery following coronary artery bypass surgery: a 10 year experience from and academic medical center. Anaesthesia, 59(5), 422-427. • Deveraux, P.J., Goldman, L., Yusuf, S., Gilbert, K., Leslie, K., & Guyatt, G.H. (2005a). Perioperative cardiac events in patients undergoing noncardiac surgery: a review of the magnitude of the problem, the pathophysiology of the events and methods to estimate and communicate risk. CMAJ, 173(7), 627-634. • Deveraux, P.J., Goldman, L., Yusuf, S., Gilbert, K., Leslie, K., & Guyatt, G.H. (2005b). Surveillance and prevention of major perioperative ischemic cardiac events in patients undergoing noncardiac surgery: a review. CMAJ, 173(7), 779-788. • Dodds, T.M., Stone, J.G., Coromilas, J., Weinberger, M., & Levy, D.G. (1993). Prophylactic nitroglycerin infusion during noncardiac surgery does not reduce perioperative ischemia. Anesthesia and Analgesia, 76(4), 705-713. • Dupuis, J.Y., & Labinaz, M. (2005). Noncardiac surgery in patients with coronary artery stent: what should the anesthesiologist know?. Canadian Journal of Anesthesia, 52 (4), 356-361. • Eagle, K.A., Rihal, C.S., Michel, M.C., Holmes, D.R., Foster, E.D., & Gersh, B.J. (1997). Cardiac risk of noncardiac surgery: Influence of coronary artery disease and type of surgery in 3368 operations. Circulation, 96(6), 1882-1887. • Ellis, J.E., Drijvers, G., Pedlow, S., Laff, S.P., Sorrentino, J.F., Foss, J.F., et al. (1994). Premedication with oral and transdermal clonidine provides safe and efficacious postoperative sympatholysis. Anesthesia and Analgesia, 75(6), 133-1140.

39. References • Frank, S.M., Fleisher, L.A., Breslow, M.J., Higgins, M.S., Olson, K.F., Kelly, S., et al. (1997). Perioperative maintenance of normothermia reduces the incidence of morbid cardiac events: A randomized clinical trial. Journal of the American Medical Association, 277(14), 1127-1134. • Hebert, P.C., Wells, G., Blajchman, M.A., Marshall, J., Martin, C., Pagliarello, G., et al. (1999). A multicenter, randomized, controlled clinical trial of transfusion requirements in critical care. The New England Journal of Medicine, 340(6), 409-417. • Houge, C.W., Goodnough, L.T., & Monk, T.G. (1998). Perioperative myocardial ischemic episodes are related to hematocrit level in patients undergoing radical prostatectomy. Transfusion, 38(10), 924-931. • Joint European Society of Cardiology & American College of Cardiology.(2000). Myocardial infarction redefined. Journal of the American College of Cardiology, 36(3), 959-969. • Joint International Society and Federation of Cardiology & World Health Organization. (1979). Nomenclature and criteria for diagnosis of ischemic heart disease. Circulation, 59(3), 607-609.

40. References • Landesberg, G. (2003). The pathophysiology of perioperative myocardial inarction: facts and perspectives. Journal of cardiothoracic and Vascular Anesthesia, 17(1), 90-100. • Landesberg, G., Morris, M., Wolf, Y., Vesselov, Y., & Weissman, C. (2002). Periopertive myocardial ischemia and infarction. Anesthesiology, 96(2), 264-270. • Landesberg, G., Mosseri, M., Zahger, D., Wolf, Y., Perouansky, M., Anner, H., et al. (2001). Myocardial infaraction after vascular surgery: The role of prolonged, stress-induced, ST depression-type ischemia. Journal of the American College of Cardiology, 37(7), 1839-1845. • London, M.J. (2002). Multilead precordial ST-segment monitoring: The next generation?. Anesthesiology, 96(2), 259-261.

41. References • London, M.J., Hollenberg, M., Wong, M.G., Levenson, L., Tubau, J.F., Browner, W., et al. (1988). Intraoperative myocardial ischemia: Localization by continuous 12-lead electrocardiography. Anesthesiology, 69(2), 232-241. • Mangano, D.T. (1990). Perioperative cardiac morbidity. Anesthesiology, 72(1), 153-184. • McFalls, E.O., Ward, H.B., Mortiz, T.E., Goldman, S., Krupski, W.C., Littooy, F., et al. (2004). Coronary-artery revascularization before elective major vascular surgery. New England Journal of Medicine, 351(27), 2795-2804. • Nyhan, D., & Roger, A.J. (2005). Anesthesia for cardiac surgery procedures. In R.D. Miller (Ed.), Miller’s Anesthesia (6th ed., pp.1941-1995).Philadelphia: Elsevier. • Morgan, E.G., Mikhail, M.S., & Murray, M.J. (2006). Clinical Anesthesiology. New York: Lang Medical Books/McGraw-Hill Medical Publishing Division. • Oliver, M.F,. Goldman, L., Julian, D.G., & Holme, I. (1999). Anesthesiology, 91(4), 951-961. • Poldermans, D., Boersma, E., Bax, J.J., Tjhomson, I.R., Louis, L.M., Ven, V.D., et al. (1999). The effect of bisoprolol on perioperative mortality and myocardial infarction in high-risk patients undergoing vascular surgery. New England Journal of Medicine, 341, 1789-1794.

42. References • Polanczyk, C.A., Marcantonio, E., Goldman, L., Rhode, L.E., Orav, J., Mangoine., et al. (2001). Impact of age on perioperative complications and length of stay in patients undergoing noncardiac surgery. Annals of Internal Medicine, 134(8), 637-643. • Raby, K.E., Brull, S.J., Timimi, F., Akhtar, S., Rosenbaum, S., Naimi, C., et al. (1999). The effect of heart rate control on myocardial ischemia among high-risk patients after vascular surgery. Anesthesia and Analgesia, 88(3), 477-482. • Reilly, D.F., McNeely, M.J., Doerner, D., Greenberg, D.L., Staiger, T.O., Geist, M.J., et al. (1999). Self-reported exercise tolerance and the risk of serious perioperative complications. Archives of Internal Medicine, 159, 2185-2192. • Rodgers, A., Walker, N., Schug, S., McKnee, A., Kehlet, H.,Van Zundert, A., et al. (2000). Reduction of postoperative mortality and morbidity with epidural or spinal anesthesia: Results from overview of randomized trials. British Medical Journal, 321 (7275) 1493-1497. • Selzman, C.H., Miller, S.A., Zimmerman, M.A., & Harken, A.H.(2001). The case for B-adrenergic blockade as prophylaxis against perioperative cardiovascular morbidity and mortality. Arch Surg, 136, 286-290.

43. References • Sista, R.R., Ernst, K.V., & Ashley E.A. (2006). Perioperative cardiac risk: pathophysiology, assessment and management. Expert Review of Cardiovascular Therapy, 4(5), 731-734. • Sprung, J., Abdelmalak, B., Gottlieb, A., Mayhew, C., Hammel, J., Levy, P.J., et al. (2000). Analysis of risk factors for myocardial infarction and cardiac mortality after major vascular surgery. Anesthesiology, 93(1), 129-140. • Symons, J.A., & Myles, P.S. (2006). Myocardial protection with volatile anaesthetic agents during coronary artery bypass surgery: A meta-analysis. British Journal of Anaesthesia, 97(2), 127-136. • Warltier, D.C., Pagel, P.S., & Kersten, J.R. (2000). Approaches to the prevention of perioperative myocardial ischemia. Anesthesiology, 92(1), 253-259. • Wijeysundera, D.N., & Beattie, W.S. (2003). Calcium channel blockers for reducing cardiac morbidity after noncardiac surgery: A meta-analysis. Anesthesia and Analgesia, 97(3), 634-641. • Wilson, S.H., Fasseas, P., Orford, J.L., Lennon, R.J., Horlocker, T., Charnoff, N.E., et al. (2003). Clinical outcome of patients undergoing non-cardiac surgery in the two months following coronary stenting. Journal of the American College of Cardiology, 42(2), 234-240.

44. Cerebral Oximetry Monitoring in Adult Cardiac Surgery Kate Busker, SRNA University of North Dakota

45. Objectives • Provide education on cerebral perfusion during adult cardiac bypass surgery. • Provide information on cerebral oximetry application, benefits, and limitations. • Discuss anesthetic interventions with cerebral oximetry.

46. Goal • To optimize care of adult cardiac bypass patients.

47. Introduction • 40% of myocardial revascularization has evidence of persistent cognitive decline (Edmonds et al. 2004) • On average, a patient ends up staying a minimum of 3 days longer in hospital (Yao, et al. 2001) • The neurological deficits seen post-cardiac bypass has accumulated an increase in patient costs up to 11% (Edmonds, 2002)

48. Cerebral Oximeter • Produced by Somanetics in Troy, MI

49. What is Cerebral Oximetry? • Utilizes Near-Infrared Spectroscopy (NIRS) • various wavelengths of infrared light that are transmitting through the skull into the cerebral tissue • Monitoring regional saturation of oxygen (rSO2) of grey matter in brain. • 75% venous and 25% arterial volume • Healthy levels of rSO2= 58% to 82%. • Data collected and displayed every 4-5 sec.

50. Research Questions • The following research questions guided this study: • 1. Does cerebral oximetry monitoring decrease the incidence of post-operative cognitive dysfunction in the adult cardiac surgical patient? • 2. Does cerebral oximetry decrease the length of hospital stays for adult cardiac surgical patients?