basic clinical anesthesia: part 2

(bq) part 2 book “basic clinical anesthesia” has contents: cardiac anesthesia, vascular anesthesia, thoracic anesthesia, ambulatory anesthesia, hepatic and gastrointestinal diseases, endocrine diseases, pediatric anesthesia, the elderly patient,… and other contents.
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basic clinical anesthesia: part 2Part IVSpecialty Anesthesia26Cardiac AnesthesiaMaheshSardesaiCardiac anesthesiology encompasses the perioperativemanagement of patients undergoing surgery on the heart andgreat vessels, as well as an increasing variety of transcatheterand other nonsurgical procedures. Cardiovascular disease isthe leading cause of death in the United States and other industrialized nations, and it comprises an increasing share of thedisease burden in the developing world. Accordingly, the fundamental principles of cardiac anesthesiology are essential notonly for cardiac surgery itself, but also for the care of patientswith various degrees of cardiovascular compromise undergoing noncardiac procedures. Therefore, optimum anestheticcare of these patients requires familiarity with cardiovascularphysiology, diagnostic evaluation, transesophageal echocardiography (TEE), cardiopulmonary bypass (CPB), cardiacsurgical techniques, and cardiac perioperative care.Cardiovascular PhysiologyThe underlying principle of perioperative management in anypatient is to maintain adequate oxygen delivery to sustain themetabolic requirements of vital organs and peripheral tissues.The ultimate goal of any cardiac surgical intervention is toprovide conditions that promote adequate tissue perfusionwith as little cardiopulmonary burden as possible.Blood PressureTissue perfusion depends on systemic blood pressure and localvascular resistance. Local vascular resistance is determined bylocal vasomotor tone. Systemic blood pressure, clinically measured with a noninvasive blood pressure cuff or an indwellingarterial catheter, is expressed as mean arterial pressure (MAP),M. Sardesai, M.D., M.B.A. (*)Department of Anesthesiology, UPMC Shadyside Hospital,5230 Centre Avenue Suite 205, Pittsburgh, PA 15232, USAe-mail: sardesaimp@upmc.edunormally between 70 and 100 mmHg. normally between70 and 100 mmHg. Pulsatile flow from cyclic cardiac contractions generates a pulse pressure, the difference betweensystolic blood pressure (SBP) and diastolic blood pressure(DBP). The five main physiologic parameters that contributeto blood pressure are heart rate, rhythm, contractility, preload,and afterload. Understanding these five parameters is essentialto developing a clinical framework for hemodynamic management (Table 26.1). At normal resting heart rates, MAP canbe estimated from measurements of SBP andDBP:MAP » 1 SBP + 2 DBP 33However, at high heart rates, changes in the shape of thearterial pulse pressure curve cause MAP to approach themean of SBP and DBP.Systemic blood pressure depends ona contribution from the heart, cardiac output (CO), and acontribution from the systemic vasculature, systemic vascular resistance (SVR):MAP = CO ´ SVR Cardiac OutputCardiac output is the volume of blood pumped by the heartinto the peripheral circulation every minute. Normal CO isapproximately 5–6 L/min in a 70kg adult male. Cardiacindex (CI), equal to CO divided by body surface area (BSA),is a normalized value that allows comparison of CO amongpeople of differing body habitus (normal CI = 2.5–4.2 L/min/m2). CO is normally identical between the right and left sidesof the heart, but certain congenital abnormalities and traumatic injuries can cause the two sides of the heart to ejectdifferent amounts of blood per cardiac cycle. CO is equal tothe product of heart rate (HR) and stroke volume (SV):CO = HR ´ SVCI = CO / BSA P.K. Sikka et al. (eds.), Basic Clinical Anesthesia,DOI10.1007/978-1-4939-1737-2_26, © Springer Science+Business Media New York 2015311312M. SardesaiTable 26.1  Overview of physiologic determinants of systemic bloodpressureHeart rateColloquialClinicalFundamentalMonitoring methodsRhythmColloquialClinicalFundamentalMonitoring methodsContractilityColloquialClinicalFundamentalMonitoring methodsPreloadColloquialClinicalFundamentalMonitoring methodsAfterloadColloquialClinicalFundamentalMonitoring methodsSA nodePulse rate, heartbeats per minutePeriodicity or frequency ofcontractionIntactness of nodal function andinnervationECG, pulse waveformsBeat pattern, ECG tracingRegularity of contractionIntactness of cardiac conductionsystemPeripheral pulse, ECG, pulsewaveformsHeart function, ejection fractionMagnitude of contraction, change inpressureIncrease in intraventricular pressureduring contraction, change in myocytelengthTEE, pulse pressure, cardiaccontractions on surgical fieldVentricular volume, dilation, volumestatusChamber volume at end diastoleMaximum myocyte stretchTEE, venous distension, distension ofheart on surgical fieldArterial squeeze, vascular tightnessResistance faced by myocardiumWork performed by myocytePA catheter, TEE (by excluding othercauses of hypotension)Heart RateHeart rate represents the periodic impulses from the native ...