Flashcards in Hemodynamic Monitoring Deck (75)
How far is an esophageal stethoscope inserted into the esophagus?
28-30cm. This allows us to hear heart sounds and BS internally.
What are precordial and esophageal stethoscopes useful for?
Continuous assessment of heart and breath sounds. Very sensitive monitor for bronchospasm and changes in pediatric patients
How often should we have a regular stethoscope available?
At all times
What 4 general things are continually evaluated?
Oxygenation, ventilation, circulation, and temperature
Considerations in deciding what type of monitoring to use
6) Skill level
Types of hemodynamic monitoring used
EKG, BP (NIBP and IABP), CVP, PAP, PCWP, TEE, stethoscope
What can the EKG tell you?
Heart rate, arrhythmias, Ischemia, electrolyte imbalances, pacemaker function
Aspects of the 3 Lead EKG
Electrodes used: RA, LA, LL
Leads: I, II, III
Number of views of the heart: 3
Aspects of the 5 lead EKG
Electrodes used: RA, LA, RL, LL, chest
Leads: I, II III, AVL, AVR, AVF, V lead
Number of views of the heart: 7
Value of the length and width of each EKG box
.1mV and .04s
How to calculate HR based on EKG lead
1500/# boxes between R waves
How should the gain be set in order to accurately assess the ST segment?
At standardization (1mV signal gives a rise of 10mm). This setting also fixes the ratio of the QRS complex to the ST segment size so that a 1mm change in the ST segment can be accurately assessed. If the wrong gain setting is used, ST changes may be under or over-diagnosed.
What filtering mode should the EKG be on for accurate ST assessment?
Diagnostic mode. Filtering out the low end of frequency bandwith (which can happen on monitor mode) can lead to ST distortion (either elevation OR depression)
5 main indicators of acute ischemia
ST elevation ( >1mm), ST depression ( >1mm), flipped Ts, peaked Ts, development of Q waves
Posterior / inferior wall ischemia is seen in these leads and is due to a blockage in this artery
II, III, AVF
Lateral wall ischemia is seen in these leadsand is due to a blockage in this artery
I, AVL, V5-6
Left circumflex coronary artery
Anterior wall ischemia is seen in these leadsand is due to a blockage in this artery
I, AVL, V1-4
Left coronary artery
Anterioseptal wall ischemia is seen in these leads and is due to a blockage in this artery
Left anterior descending coronary artery
This part of BP correlates to the point of the most demand on the heart
The pulse pressure changes as you move from where to where
From the central arterial system to the periphery. The pulse pressure widens due to wave reflections in the vasculature.
These factors can cause a falsely high NIBP reading
Cuff too small, cuff below the level of the heart, loose cuff, arterial stiffness (HTN, PVD)
These factors can cause a falsely low NIBP reading
Cuff too large, cuff above the level of the heart, poor tissue perfusion, deflation is too rapid
Fals NIBP reading can also occur with
Cardiac dysrhythmia, tremors/shivering/ and improper cuff placement
This type of NIBP reading only gives you SBP
Palpation. It measures the return of arterial pulse during deflation. This is simple, inexpensive, and underestimates the SBP.
This NIBP reading only gives you SBP but measures it fairly reliably
Doppler. Measures it by a shift in frequency of sound waves that is reflected by RBCs moving through an artery.
This NIBP method estimates both SBP and DBP
Auscultation with a sphygmomanometer. Measures BP by auscultation Karotkoff sounds created by turbulent blood flow though the artery created by the mechanical deformation from the BP cuff. This method is unreliable in patients with HTN.
Changes in SBP correlate with changes in ____
Myocardial O2 demand.
Automated cuffs work by this mechanism
Complications of NIBP measurement
Ulnar nerve damage, compartment syndrome, edema of the extremity, bruising / petechiae, pain, interference of IV flow, altered timing of IV drug administration