190617_Hemodynamics Flashcards
AANA Standard 9: Monitoring and Alarms
• Monitor, evaluate, and document the patient’s physiologic condition as appropriate for the procedure and anesthetic technique.
• When a physiological monitoring device is used, variable pitch and threshold alarms are turned on and audible.
• Document blood pressure, heart rate, and respiration at least every five minutes for all anesthetics.
**Required: EKG, Blood Pressure, Temp, Pule Ox, ETCO2
***Other: As indicated
Oxygenation
Continuously monitor oxygenation by clinical observation and pulse oximetry. The surgical or procedure team communicates and collaborates to mitigate the risk of fire.
Ventilation
Continuously monitor ventilation by clinical observation and confirmation of continuous expired carbon dioxide during moderate sedation, deep sedation or general anesthesia. Verify intubation of the trachea or placement of other artificial airway device by auscultation, chest excursion, and confirmation of expired carbon dioxide. Use ventilatory monitors as indicated.
Cardiovascular
Monitor and evaluate circulation to maintain patient’s hemodynamic status. Continuously monitor heart rate and cardiovascular status. Use invasive monitoring as appropriate.
Thermoregulation
When clinically significant changes in body temperature are intended, anticipated, or suspected, monitor body temperature. Use active measures to facilitate normothermia. When malignant hyperthermia (MH) triggering agents are used, monitor temperature and recognize signs and symptoms to immediately initiate appropriate treatment and management of MH.
Neuromuscular
When neuromuscular blocking agents are administered, monitor neuromuscular response to assess depth of blockade and degree of recovery.
Non-Invasive Blood Pressure Measurement
•Palpation- palpating the return of arterial pulse while on occluded cuff is deflated
-Underestimates systolic pressure, simple, inexpensive, measures only SBP.
•Doppler- based on shift in frequency of sound waves that is reflected by RBCs moving through an artery
-Measures only SBP reliably.
•Auscultation- using a sphygmomanometer, cuff, and stethoscope; Korotkoff sounds due to turbulent flow within an artery created by mechanical deformation from BP cuff (unreliable in HTN pts-usually lower)
-Permits estimation SBP and DBP
Non-Invasive Blood Pressure Measurement-Cont
•Oscillometry- Senses oscillations/fluctuations in cuff pressure produced by arterial pulsations while deflating a BP cuff
-1st oscillation correlates with SBP
-Maximal degree of detectable pulsation is determined to be the MAP
-Oscillations cease at DBP
•Automated cuffs work by this mechanism-measure changes in oscillatory amplitude electronically, derives MAP, SBP, DBP by using algorithms
-Continuous NIBP finger readings:
-Subject to significant limitations
Complications of Non-Invasive Blood Pressure Measurement
Pain Petechiae and ecchymoses Limb edema Vesus Stasis and thrombophlebitis Peripherial neuropathy Compartment syndrome
Blood Pressure- Arterial Line (A-line)
Systemic arterial pressure waveform results from ejection of blood from the left ventricle into the aorta during systole, followed by peripheral runoff during diastole
Percutaneous arterial catheter
-Transduced to convert the generated pressure into an electrical signal to provide a waveform
–Generates real-time beat to beat BP
–Allows access for arterial blood samples
–Measurement of CO/ CI/ SVR~need CVP
Indication for Arterial Cannulation
Continuous, realtime blood pressure monitoring
Planned pharmacological or mechanical cardiovasular manipulatipon
Repleated blood sampling
Failure of indirect arteriol blood pressure measurement
Supplamentory diagnostic infro from arterial waveform
- Elective deliberate hypotension
- Wide swings in intra-op BP
- Risk of rapid changes in BP
- Rapid fluid shifts
- Titration of vasoactive drugs
- End organ disease
- Repeated blood sampling
- Failure of indirect BP measurement
underdamped arterial waveform
displays systolic pressure overshoot and may contain elements produced by the measurement system itself rather than the original propagated pressure wave • Catheter whip or artifact • Stiff non-compliant tubing • Hypothermia • Tachycardia or dysrhythmia
overdamped arterial waveform
recognizable by its slurred upstroke, absent dicrotic notch, and loss of fine detail. Such waves display a falsely narrowed pulse pressure, although MAP may remain reasonably accurate • Loose connections • Air bubbles • Kinks • Blood clots • Arterial spasm • Narrow tubing
Actions: Damped Waveforms
✓Pressure bag inflated to 300 mmHg ✓Reposition extremity or patient ✓Verify appropriate scale ✓Flush or aspirate line ✓Check or replace module or cable
Complications of direct arterial pressure monitoring
Nerve Damage Hemorrhage/ Hematoma Infection Thrombosis Air embolus Skin necrosis Loss of digits Vasospasm Arterial aneurysm Retained guide wire
Misinterpretation of data
Misuse of equipment
Aortic regurgitation
produces a bisferiens pulse (double peak)
and a wide pulse pressure.
Hypertrophic cardiomyopathy
peculiar spike-and-dome configuration
The waveform assumes a more normal morphology following surgical correction of this condition.
Systolic Left ventricular failure
Pulsus alternans (alternating PP amplitude)
Systolic Left ventricular failure
Pulsus alternans (alternating PP amplitude) ~fluid responsive
Beer’s Law
relates the concentration of a dissolved substance to the log of the ratio of the incident and transmitted light intensity through a known distance.
Causes of false readings
Malposition of probe Dark nail polish Different hemoglobin Dyes Electrical interference Shivering/pt movement Systolic blood pressures lower than 80 mm Hg Ambient light Low perfusion (weak pulse)
Causes of false readings
Malposition of probe Different hemoglobin Dyes Electrical interference Systolic blood pressures lower than 80 mm Hg Ambient light Low perfusion (weak pulse)
Hypotension = decreased Anemia = decreased Shivering/pt movement = decreased Dark nail polish = decreased IABP = increased Low SaO2 = variable Skin pigmentation (SaO2<80%) = increased Methemoglobinemia = variable (SpO2 approaches 85%)? Carboxyhemoglobinemia = increased Hemoglobin K = decreased Methylene Blue = decreased Indego carmine = decreased Indocyanine green = decreased
**Does NOT provide info on acid-base status
Oxyhemoglobin Dissociation Curve
SLIDE 49 & slide notes!!!! MUST KNOW
Central Venous Catheters (CVC)
administration of vasoactive drugs or fluids prolonged abx treatment chemo and other paripharial irritants rapid infusion CVP monitoring transvenous cardiac pacing temporary hemodialysis pulmonary artery catheterization aspiration of entrained air sampling site for repeated blood testing inadequate peripheral access
CVP normal waveform related to the cardiac cycle
SLIDE 59!!! KNOW
CVP normal waveform related to the cardiac cycle
SLIDE 59-66!!! KNOW
- Identify surgical procedures for which PA lines are placed and the hemodynamic parameters measured.
SLIDES 68-82!!!
Review the EKG complex, indications for a 12 lead, lead placement, and the primary intraoperative leads utilized.
SLIDES 9-22!!!
TEE
SLIDES 84-88!!!
