1 / 17

Cardiac Assessment in the OR: Troubleshooting when coming off bypass

Cardiac Assessment in the OR: Troubleshooting when coming off bypass. Kimberly D. Milhoan, MD Assistant Clinical Professor, University of Texas Health Science Center, San Antonio, TX 2011 Cardiac Critical Care Course Kathmandu, Nepal October 17, 2011. Cardiac Bypass:

quinn-terrell
Download Presentation

Cardiac Assessment in the OR: Troubleshooting when coming off bypass

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Cardiac Assessment in the OR: Troubleshooting when coming off bypass Kimberly D. Milhoan, MD Assistant Clinical Professor, University of Texas Health Science Center, San Antonio, TX 2011 Cardiac Critical Care Course Kathmandu, Nepal October 17, 2011

  2. Cardiac Bypass: Pre-operative evaluation Sedation outside OR Induction in OR Pre-bypass Initiation of bypass Maintenance of bypass Re-warming Separation from bypass Post-bypass (Extubation) Transport to ICU Anesthetic Order of Events

  3. Maintenance of Bypass • ASD • Temperature maintained • Heart fibrillated • Most other lesions • Temperature cooled • If intra-cardiac, aortic cross-clamp placed and cardioplegia given

  4. Re-warming phase • Target temperature: 36.5 – 37.5 C • Use “Bair hugger,” warming blanket, humidified circuit and/or Humidivent • Consider redose of sedation, muscle relaxant, narcotic • Give H1- and H2-blockers and anti-arrhythmics (magnesium sulfate or lidocaine) • Start vasoactive drips, e.g. milrinone 50 mcg/kg bolus; 0.3-0.7mcg/kg/min

  5. Re-warming phase • Prior to removal of cross-clamp • Echocardiographer looks for intracardiac air • Begin ventilation • Pulmonary toilet: suction, (albuterol)

  6. Re-warming phase • After removal of cross-clamp • Spontaneous cardiac activity • If not, check ABG and electrolytes • If ventricular fibrillation, direct cardiac defibrillation; consider more anti-arrhythmics • If ST-segment depression/elevation, look for intracardiac air • If non-sinus rhythm, consider cardiac pacing

  7. Re-warming phase • Check ABG and electrolytes • Correct base deficit: Vd x base deficit x wt in kg  give half of calculated dose in meq (Vd: 0.4 in infants, 0.3 in children/adolescents, 0.2 in adults) • Correct calcium (approximately 40 mg/kg)--give calcium after cross-clamp removal and patient is warmer than 34 degrees Celsius • Correct potassium (1 meq/kg over 10 minutes if <3.0)

  8. Criteria for Separation from Bypass • Patient warm (36 degrees Celsius) • ABG and electrolytes normal • Hematocrit adequate • Sinus rhythm at appropriate rate • Effective ventilation • Appropriate vasoactive drips • Adequate repair

  9. Separation from Bypass • After usually at least 10 minutes of cardiac activity, allow heart to fill and eject (partial bypass) to assess cardiac function, hemodynamics

  10. Separation from Bypass:Troubleshooting • Philosophies: • Consider one problem, one solution at a time • Use direct observation of heart/surgical field • Use all monitors • Consider where you are in procedure • Consider returning to previous condition • Consider potential post-operative risks of repair undertaken

  11. Separation from Bypass:Troubleshooting • On either partial bypass or after removal from bypass: • Repair or rhythm issues • Hypovolemia (low BP & low CVP): give volume • LV failure (low BP & normal/high CVP): afterload reduction, inotropes • RV failure (low BP, high CVP): pulmonary vasodilator, assess oxygenation/ventilation and acid/base status • Vasodilation (low BP, normal/low CVP): consider increasing hematocrit

  12. Resources • Andropoulos DB, Stayer SA, and Russell IA. Anesthesia for Congenital Heart Disease. Malden: Futura, 2005. • Lake CL and Booker PD. Pediatric Cardiac Anesthesia, 4th edition. Philadelphia: Lippincott, Williams, & Wilkins, 2005. • Morgan, G. Edward et al. Clinical Anesthesiology, 3rd ed. New York: Appleton & Lange, 2002.

More Related