الفهرس 
PericardiumOnly 14 pages are availabe for public view
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Abstract
Intraoperative cardiovascular monitoring involves both invasive and noninvasive strategies to assess circulation for reduction of morbidity and mortality of cardiac patients in noncardiac surgery.
Intraoperative cardiac assessment includes:
1-Peripheral pulse.
2-Electrocardiography (ECG).
3-Cardiac enzymes.
4-Electrolytes.
5-Tissue perfusion.
6-Arterial blood pressure.
7-Pulmonary artery catheter monitoring.
8-Central venous pressure monitoring.
9-Transesophageal echocardiography (TEE).
10-Cardiac output monitoring.
11-Measurement of blood loss.
The pulse oximeter plethysmograph trace is the most common source for measurement of the pulse rate, Other pulse rate sources include the directly measured arterial pressure waveform and automatic noninvasive blood pressure (NIBP) monitors, which determine the pulse rate from the pressure oscillations detected by the surrounding cuff.
The intraoperative use of the electrocardiogram (ECG) has increased during the last several decades. Originally, this monitor was used during anesthesia for the detection of dysrhythmias only in high-risk patients. ECG faciliates the intraoperative diagnosis of dysrhythmias and myocardial ischemia.
Cardiac markers are biomarkers measured to evaluate heart function. They are often discussed in the content of myocardial infarction, but other conditions can lead to an elevation in cardiac marker level. Most of the early markers identified were enzymes, and as a result, the term ”cardiac enzymes” is sometimes used.
The introduction of echocardiography into clinical practice represents one of the most important medical achievements. Transesophageal echocardiography (TEE) as an imaging technique in intra-operative patient monitoring provides dramatic non invasive imaging of the heart and great vessels as well as permitting quantification of blood flow and over all cardiac performance without interrupting the surgical procedure.
Blood pressure is a fundamental cardiovascular vital sign and a critical part of monitoring anesthetized or seriously ill patients. The importance of monitoring this vital sign is underscored by the fact that standards for basic anesthetic monitoring mandate measurement of arterial blood pressure at least every 5 minutes in all anesthetized patients. Techniques for measuring blood pressure fall into two major categories: indirect cuff devices and direct arterial cannulation and pressure transduction.
Cannulation of a large central vein is the standard clinical method for monitoring CVP and is also performed for a number of additional therapeutic interventions, such as providing secure vascular access for the administration of vasoactive drugs or to initiate rapid fluid resuscitation. Frequently, the central venous location is the only site available for intravenous access of any kind. Patients at risk for venous air emboli may have central venous catheters placed for aspiration of entrained air. In addition, central venous access is required to initiate transvenous cardiac pacing, temporary hemodialysis, or pulmonary artery catheterization for more comprehensive cardiac monitoring.
Swan, Ganz, and colleagues introduced pulmonary artery catheterization into clinical practice for hemodynamic assessment of patients with acute myocardial infarction. These catheters allowed accurate measurement of important cardiovascular physiologic variables at the bedside, and their popularity soared. The PAC provides measurements of several hemodynamic variables that many clinicians, including experts in intensive care, cannot predict accurately from standard clinical signs and symptoms. However, it remains uncertain whether PAC monitoring leads to improved patient outcome.
Cardiac output is the total blood flow generated by the heart, and in a normal adult at rest it ranges from 4.0 to 6.5 L/min. Measurement of cardiac output provides a global assessment of the circulation, and when combined with other hemodynamic measurements (heart rate, arterial blood pressure, CVP, PAP, and PAWP), it allows calculation of additional important circulatory variables such as systemic vascular resistance (SVR), PVR, and ventricular stroke work.