Podcast
Questions and Answers
What is an advantage of continuous ST-segment monitoring compared to serial 12-lead ECG recordings?
What is an advantage of continuous ST-segment monitoring compared to serial 12-lead ECG recordings?
- Electrodes can be easily moved around
- It is more cost-effective
- It requires less technical expertise
- Electrodes stay in place and do not vary (correct)
What can cause baseline ST-segment abnormalities and reduce the specificity of standard ECG criteria for diagnosing myocardial ischemia?
What can cause baseline ST-segment abnormalities and reduce the specificity of standard ECG criteria for diagnosing myocardial ischemia?
- Early repolarization and intraventricular conduction delays
- Myocardial infarction and cardiac tamponade
- Pericarditis and digitalis
- All of the above (correct)
What can be used to distinguish positional ST-segment changes from true ST-segment deviations?
What can be used to distinguish positional ST-segment changes from true ST-segment deviations?
- Changes in the QRS complex (correct)
- Changes in the T-wave
- Changes in the P-wave
- Changes in the PR interval
What do most cardiac monitors with ST-segment monitoring software provide?
What do most cardiac monitors with ST-segment monitoring software provide?
Why may changes in body position cause false ST-segment alarms?
Why may changes in body position cause false ST-segment alarms?
What is a potential limitation of using standard ECG criteria for diagnosing myocardial ischemia in patients with preexisting ECG abnormalities?
What is a potential limitation of using standard ECG criteria for diagnosing myocardial ischemia in patients with preexisting ECG abnormalities?
What is the primary advantage of using an anterolateral precordial lead (V3, V4, or V5) in ECG monitoring?
What is the primary advantage of using an anterolateral precordial lead (V3, V4, or V5) in ECG monitoring?
What is the most commonly observed form of perioperative ischemia?
What is the most commonly observed form of perioperative ischemia?
What type of ischemia is indicative of the myocardial territory and coronary artery involved?
What type of ischemia is indicative of the myocardial territory and coronary artery involved?
What is the common technique used by automated noninvasive arterial blood pressure measuring devices?
What is the common technique used by automated noninvasive arterial blood pressure measuring devices?
In which patients should caution be exercised when using automated noninvasive arterial blood pressure measuring devices?
In which patients should caution be exercised when using automated noninvasive arterial blood pressure measuring devices?
What is the primary importance of ECG monitoring in noncardiac surgery?
What is the primary importance of ECG monitoring in noncardiac surgery?
What is the reported sensitivity of simultaneously examining leads II, V4, and V5 for ischemia detection?
What is the reported sensitivity of simultaneously examining leads II, V4, and V5 for ischemia detection?
Which of the following ECG leads was found to be the most sensitive for detecting perioperative ischemia?
Which of the following ECG leads was found to be the most sensitive for detecting perioperative ischemia?
What is the minimum ST-segment change required for detection of ischemia in a single lead?
What is the minimum ST-segment change required for detection of ischemia in a single lead?
What is the minimum duration required for ST-segment changes to be considered significant?
What is the minimum duration required for ST-segment changes to be considered significant?
In which type of surgery is ECG monitoring particularly important for detecting ischemia?
In which type of surgery is ECG monitoring particularly important for detecting ischemia?
What is the term for the abnormal elevation of the ST segment on an ECG, as seen in ischemia?
What is the term for the abnormal elevation of the ST segment on an ECG, as seen in ischemia?
What is the term for the type of ischemia that occurs in the deeper layers of the heart muscle?
What is the term for the type of ischemia that occurs in the deeper layers of the heart muscle?
What is the benefit of using waveform analysis in physiological monitoring?
What is the benefit of using waveform analysis in physiological monitoring?
What is the primary advantage of using ultrasound guidance in radial artery cannulation?
What is the primary advantage of using ultrasound guidance in radial artery cannulation?
What is used to indicate preload reserve and volume responsiveness in cardiac monitoring?
What is used to indicate preload reserve and volume responsiveness in cardiac monitoring?
What is the primary limitation of using radial artery cannulation?
What is the primary limitation of using radial artery cannulation?
What is the benefit of using ultrasound guidance in catheterization of other vessels beyond the radial artery?
What is the benefit of using ultrasound guidance in catheterization of other vessels beyond the radial artery?
What is used to trigger intra-aortic balloon counterpulsation?
What is used to trigger intra-aortic balloon counterpulsation?
What is the benefit of using radial artery cannulation in cardiac monitoring?
What is the benefit of using radial artery cannulation in cardiac monitoring?
What is a limitation of thermodilution cardiac output monitoring?
What is a limitation of thermodilution cardiac output monitoring?
What is mixed venous hemoglobin oxygen saturation a measure of?
What is mixed venous hemoglobin oxygen saturation a measure of?
What percentage of information used in monitoring a patient's cardiovascular status comes from electronic devices?
What percentage of information used in monitoring a patient's cardiovascular status comes from electronic devices?
What type of monitoring is improved when considering both in monitoring and clinical evaluation?
What type of monitoring is improved when considering both in monitoring and clinical evaluation?
What can affect the accuracy of mixed venous hemoglobin oxygen saturation measurement?
What can affect the accuracy of mixed venous hemoglobin oxygen saturation measurement?
What is a common technique used in cardiovascular monitoring?
What is a common technique used in cardiovascular monitoring?
What is a limitation of using pulmonary artery wedge pressure to estimate left atrial pressure?
What is a limitation of using pulmonary artery wedge pressure to estimate left atrial pressure?
What is a reason why pulmonary artery catheter monitoring has not been shown to improve patient outcomes?
What is a reason why pulmonary artery catheter monitoring has not been shown to improve patient outcomes?
What is a confounding factor that affects the use of central venous pressure as an estimate of left ventricular preload?
What is a confounding factor that affects the use of central venous pressure as an estimate of left ventricular preload?
What is a limitation of using central venous, pulmonary artery diastolic, or pulmonary artery wedge pressures as estimates of left ventricular preload?
What is a limitation of using central venous, pulmonary artery diastolic, or pulmonary artery wedge pressures as estimates of left ventricular preload?
Why is pulmonary artery wedge pressure not a reliable measure of left atrial pressure in all cases?
Why is pulmonary artery wedge pressure not a reliable measure of left atrial pressure in all cases?
What is a potential problem with hemodynamic therapies guided by specific hemodynamic indices?
What is a potential problem with hemodynamic therapies guided by specific hemodynamic indices?
What is a disadvantage of using central venous catheters?
What is a disadvantage of using central venous catheters?
Why has pulmonary artery catheter monitoring not been shown to improve patient outcomes?
Why has pulmonary artery catheter monitoring not been shown to improve patient outcomes?
Study Notes
Cardiovascular Monitoring
- Electrocardiogram (ECG) monitoring provides continuous monitoring of heart rate, identification of arrhythmias and conduction abnormalities, and detection of myocardial ischemia.
ECG Monitoring Considerations
- Accurate and reliable ECG monitoring requires attention to lead placement and selection, choice of filter, and gain that will influence the displayed ECG tracing.
- An anterolateral precordial lead (V3, V4, or V5) should be selected for the most sensitive detection of myocardial ischemia.
ST-Segment Changes
- Demand-mediated subendocardial ischemia resulting in ST-segment depression is the most commonly observed form of perioperative ischemia.
- ST-segment depression is most commonly observed in an anterolateral precordial lead regardless of the coronary territory responsible.
- Supply-mediated transmural ischemia resulting in ST-segment elevation is uncommonly observed intraoperatively except during cardiac operations.
- ST-segment elevation is indicative of the myocardial territory and coronary artery involved.
Arterial Blood Pressure Measurement
- Most automated noninvasive arterial blood pressure measuring devices use an oscillometric measurement technique and rarely cause complications.
- Caution should be exercised in patients who cannot complain of arm pain, those with irregular rhythms that force repeated cuff inflation, and those receiving anticoagulant therapy.
ST-Segment Monitoring Advantages
- One major advantage of continuous ST-segment monitoring is that the electrodes stay in place and do not vary as they may with serial 12-lead ECG recordings.
Limitations of ST-Segment Monitoring
- Many patients have preexisting ECG abnormalities that confound interpretation of ST-segment changes.
- Changes in body position may cause ST-segment changes and lead to false ST-segment alarms.
- Early repolarization, intraventricular conduction delays, LV hypertrophy, digitalis, pericarditis, and other conditions may cause baseline ST-segment abnormalities.
Cardiac Monitor Software
- Most cardiac monitors with ST-segment monitoring software provide displays of ST-segment trends in a single lead or the sum of absolute ST-segment deviations from multiple leads.
- Monitoring continuous 12-lead ST-segment changes greater than 0.2 mV from baseline in a single lead or more than 0.1 mV in two contiguous leads at J+60 ms, lasting longer than 10 minutes, can detect perioperative ischemia.
- Leads V3 and V4 are more sensitive than V5 in detecting perioperative ischemia.
Central Venous and Pulmonary Artery Catheters
- Catheter misuse and data misinterpretation are common complications of central venous and pulmonary artery catheters
- Pulmonary artery wedge pressure is a delayed and damped reflection of left atrial pressure and may underestimate capillary pressure in patients with sepsis
Limitations of Catheter-Derived Data
- Use of central venous, pulmonary artery diastolic, or pulmonary artery wedge pressures as estimates of left ventricular preload is subject to many confounding factors
- Pulmonary artery catheter monitoring has not been shown to improve patient outcomes due to misinterpretation of catheter-derived data and failure of hemodynamic therapies
Cardiac Output Monitoring
- Thermodilution cardiac output monitoring is subject to measurement errors introduced by rapid intravenous fluid administration, intracardiac shunts, and tricuspid valve regurgitation
- Mixed venous hemoglobin oxygen saturation is a measure of the adequacy of cardiac output relative to body oxygen requirements
Hemodynamic Monitoring
- Electronic devices provide the majority of information used in monitoring a patient's cardiovascular status
- Waveform analysis in physiologic monitoring has become more popular and can be used to indicate preload reserve and volume responsiveness
- Arterial pressure waveform characteristics include the dicrotic notch and respiratory-induced variation in pressure measurements
Arterial Blood Pressure Monitoring
- Techniques for radial artery cannulation have been unchanged for decades, but the use of ultrasound in guiding catheter placement has improved first-pass cannulation success rates
- Ultrasound guidance in catheterization of other vessels or in special populations may be of substantial benefit
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
This quiz covers the key points of cardiovascular monitoring, including ECG monitoring, lead placement, and identification of arrhythmias and conduction abnormalities.
