Chapter 14: Hemodynamic Monitoring

Lecture

I. Introduction
	Time: 6 Minutes
	Slides: 1–4
	Lecture/Discussion
A. 	History
1. 	Mechanically assisted ventilation was introduced in the 1960s.
2. 	The pulmonary artery catheter (PAC) was introduced in the 1970s.
B. 	Invasive hemodynamic monitoring
1. 	Hemodynamic assessment allows health care providers to monitor the heart, vascular network, and fluid volume.
2. 	The technology can aid CCTP in assessing a patient’s condition and the effectiveness of interventions. 
3. 	The technology can warn CCTP of any deterioration in the patient’s condition.
4. 	Invasive hemodynamic monitoring can contribute to sepsis, thrombophlebitis, thromboembolism, and tissue injury.
5. 	Measurements are easily misread.
6. 	Catheter placement is usually outside of the scope of CCTP.
C. 	Asepsis
1. 	Insertion of catheters bears the risk of introducing bacterial and fungal infections.
2. 	The mortality of blood stream infections in patients is around 20%.
3. 	Hand hygiene, maximal barrier precautions during insertion, chlorhexidine skin antisepsis, optimal catheter site selection, and prompt removal of unnecessary lines are all ways to avoid infection.

II. Noninvasive Hemodynamic Monitoring
	Time: 6 Minutes
	Slides: 5–8
	Lecture/Discussion
A. 	CCTP should still use physical assessments including capillary refill, skin color, skin turgor, skin temperature, lung sounds, heart sounds, and mental status.
B. 	Blood pressure
1. 	Direct monitoring uses an arterial line.
2. 	Indirect monitoring can be done using a blood pressure cuff. 
a. 	Systolic blood pressure is the measure of blood pressure on the arterial walls during systole (myocardial contraction).
b. 	Diastolic blood pressure is the measure of blood pressure on the arterial walls during diastole (when the heart is refilling).
3. 	Other indirect blood pressure monitoring methods include checking pulses, using electronic blood pressure cuffs (also known as noninvasive blood pressure (NIBP) units, 	and Doppler sound machines.
4. 	It is important that CCTP use the right size measuring equipment for their patients. Improper equipment can give inaccurate readings.
5. 	CCTP must also be sure to position the equipment they are using correctly.
6. 	NIBP units are often incorporated into transport monitors and are used to take readings at preestablished intervals.
a. 	NIBP units measure heart rate and mean arterial pressure (MAP) only. 
b. 	CCTP should compare the instrument readings to the patient’s own pulse rate, the heart rate in a pulse oximeter, or on an ECG.
c. 	If the readings are very different, CCTP should defer to information obtained during physical monitoring.
C. 	Allen test
1. 	This test assesses extremity perfusion and ulnar artery function. 
2. 	Color should return to the patient’s hand within 6 seconds.

III. Invasive Hemodynamic Monitoring
	Time:  47 Minutes
	Slides: 9–39
	Lecture/Discussion
A. 	CCTP do not normally place catheters, but they provide transportation to patients who are using them.
B. 	Central venous lines
1. 	Introduction
a. 	These catheters are placed inside the central venous system and provide access to the core vessels of the body.
b. 	The right internal jugular vein is the easiest site to access. 
c. 	Subclavian sites are preferable because they minimize infection risks. 
d. 	Femoral and brachial veins are also common sites. 
e. 	Femoral lines are strongly discouraged in adults because they have a high risk of infection.
f. 	The catheter is inserted until the tip resides just outside the right atrium (in the superior vena cava). 
i. 	This position allows for central venous pressure (CVP) readings. 
ii. 	Monitoring of the CVP is used to determine right ventricular preload and intravascular volume status and to assess right-sided heart function. 	
iii. 	The normal range for the CVP is 2 to 6 mm Hg. 
g. 	Most patient care monitors designed for critical care measure the CVP with a presumption that the patient is being mechanically ventilated.
2. 	Indications
a. 	Rapid fluid replacement
b. 	Medication administration
c. 	Rapid access to central circulation
d. 	Invasive monitoring
3. 	Contraindications
a. 	Significant coagulopathy
b. 	Trauma to the insertion site
c. 	Infection at site of insertion
4. 	Complications
a. 	The most common complication is pneumothorax and hemothorax from attempting subclavian insertion.
b. 	Many other complications include air embolism, infection, thrombosis, phlebitis, limb ischemia, arterial puncture, improper placement, myocardial perforation, thoracic duct injury, nerve injury, catheter occlusion, sluggish infusion, catheter damage, and blood withdrawal problems.
C. 	Types of central venous catheters
1. 	Triple-lumen catheter
a. 	All three lumens can be used for phlebotomy or for fluid and drug administration. 
b. 	Two lumens can be used for fluid administration with the other being used for other for monitoring CVP.	
2. 	HICKMAN®
a. 	This is a semipermanent central venous catheter used for venous access and for drawing blood. 
b. 	Placement of this line can be into the cephalic, subclavian, external, or internal jugular vein. 
c. 	The catheter exits from the lower portion of the anterior chest wall via a subcutaneous tunnel. 
d. 	Daily flushing of this line is necessary to prevent it from clotting and is also required every time the line is used to draw blood.
e.  	Complications include clotting of the line, catheter breakage, and infection.
f. 	Catheter infection often presents as bacteremia, with fever and chills progressing into septic shock. 
3. 	GROSHONG®
a. 	This catheter is thinner, is more flexible, can have up to three lumens, and is equipped with a subcutaneous cuff. 
b. 	The catheter exits the skin near the nipple.
c. 	There is a pressure-sensitive, two-way valve on the adjacent lateral wall that allows for the tip of the catheter to be closed.
d. 	Because venous pressure maintains the valve in the closed position, there is no backflow of blood into the catheter. 
e. 	The advantages of this design are that clamping and frequent heparin flushing are not necessary.
f. 	This catheter can also last between 6 weeks and 6 months. 
4. 	Port-a-cath
a. 	The port-a-cath is a titanium chamber with a catheter that threads under the skin into the subclavian vein to the right atrium. 
b. 	The titanium chamber has a self-sealing rubber top, which is implanted under the skin of the anterior part of the chest. 
c. 	The catheter can be used for the infusion of fluid or medications and for blood draws. 
d. 	A Huber needle can be used to give medications or draw blood. 
e. 	This catheter can remain in place for years. 
5. 	Peripherally inserted central catheter (PICC)
a. 	This catheter is used when medium-duration, long-term access is needed. 
b. 	This catheter is inserted via the brachial or other arm vein and is advanced to the superior vena cava, with the tip of the line just outside the atrium. 
c. 	The PICC requires regular flushing with heparin or saline solution to prevent clotting. 
d. 	Low-dose warfarin may be added to the patient’s daily medications to augment line patency if clotting problems have occurred in the past. 
e. 	The disadvantages of this catheter include limited arm mobility and limitations on aggressive exertion. 
D. 	Central venous catheter placement
1. 	Equipment
a. 	Catheters (various sizes and lengths)
b. 	5- and 10-mL syringes
c. 	Saline flush solution
d. 	Chlorhexidine–isopropyl alcohol solution
e. 	J-tipped guide wire
f. 	IV tubing
g. 	IV fluids
h. 	Suture materials
i. 	Occlusive dressing
j. 	Sterile drape
k. 	Tape
l. 	Local anesthetic
2. 	Skill Drill 14-1: Inserting a Central Venous Line
a. 	Use universal precautions.
b. 	Prepare all equipment and flush all lumen ports.
c. 	Locate landmarks.
d. 	Palpate for entry location.
e. 	Clean and prepare the site.
f. 	Administer a local anesthetic.
g. 	Insert the needle with connected syringe at the site, aspirating until blood is drawn into the syringe.
h. 	Remove the syringe and insert the guide wire into the needle. Feed the needle into the vein.
i. 	Remove the needle while holding the guide wire in place. 
j. 	Insert the catheter over the guide wire and into the vessel, removing the guide wire as the catheter advances.
k. 	Aspirate blood and flush all ports to ensure patency.
l. 	Secure the line to the patient’s skin using sutures or staples.
m. 	Dress the site and take a radiograph to ensure proper line placement.
3. 	Troubleshooting
a. 	Problems include sluggish infusion, inability to withdraw blood, and catheter damage.
E. 	Arterial lines
1. 	Introduction
a. 	Arterial lines (A-lines) are inserted into the patient’s arterial vascular system. 
b. 	The transducer converts the pressure waveform into an electrical signal and displays the waveform and its corresponding values on the transport monitor. 
c. 	Arterial lines may be inserted in the radial, brachial, femoral, axillary, and dorsalis pedis arteries.
d. 	The radial artery is the preferred site. 
e. 	The arterial line is an alternative trigger source for an intra-aortic balloon pump and enables access for sampling and blood gas analysis.
2. 	Indications
a. 	Patients who require constant BP measurement
b. 	Patients with low flow states or high SVR conditions
c.	Patients in shock who are not responding to therapy
d. 	Patients receiving vasoactive or antihypertensive infusions
3. 	Contraindications
a. 	Ischemia of the extremity
b. 	Infection at the puncture site
c. 	Raynaud disease
d. 	Prior vascular surgery in the area of the insertion site
4. 	Complications
a. 	Arterial line thrombosis
b. 	Embolization
c. 	Hematoma
d. 	Insertion site infection
e. 	Median nerve neuropathy
f. 	Pseudoaneurysm of the artery
g. 	Ischemic necrosis
h. 	Digit, hand, leg, or foot ischemia
i. 	Hemorrhage
j. 	Arterial air embolism
k. 	Arteriovenous fistula
l. 	Arterial aneurysm
F. 	Arterial line placement
1. 	Equipment
a. 	20-gauge radial over-the-needle catheterization kit with guide wire
b. 	18- to 20-gauge 6” femoral artery catheterization kit with guide wire
c. 	Tape
d. 	Sterile 2”  2” gauze sponges; 4”  4” gauze sponges
e. 	Local anesthetics
f. 	Sedation medications
g. 	Sterile gloves, gown, mask, and drapes
h. 	Chlorhexidine–isopropyl alcohol solution
i. 	Pressure transducer
j. 	Tubing
k. 	Pressure monitor
l. 	Suture material or commercial suture kit
2. Skill Drill 14-2: Inserting an Arterial Line
a. 	Use universal precautions.
b. 	Prepare the equipment.
c. 	Position the patient by placing rolled gauze under the wrist, hyperextending the wrist.
d. 	Select and clean the insertion site; ensure IV access.
e. 	Palpate the artery at the distal radius.
f. 	Anesthetize the area.
g. 	Insert the needle over the radial artery 1cm distal to the wrist joint.
h. 	Advance the needle at an approximately 20° to 45° angle.
i. 	Immobilize the needle.
j. 	Advance the guide wire, and then remove the needle.
k. 	Place the arterial catheter over the guide wire.
l. 	Remove the guide wire, leaving only the cannula in place.
m. 	Connect the tubing to the pressure transducer.
n. 	Secure the catheter to the skin with sutures, and apply a dressing to the insertion site.
G. 	Pulmonary artery catheters (PAC)
1. 	Introduction
a. 	A PAC is inserted into the venous system of a patient. 
b. 	The PAC is a flow-directed catheter with a balloon at the tip that allows blood flow to carry the catheter through the heart into the pulmonary artery. 
c. 	The PAC is also known as a Swan-Ganz catheter (or simply a “swan”) after Harold Jeremy Swan and William Ganz, who introduced it in 1970.
d. 	A PAC uses the same access routes as a central line. 
e. 	The PAC is fed into the vena cava and then through the right atrium.
f. 	Once past the lumen of the introducer sheath, the catheter tip balloon is inflated with 1.5 mL of air to help facilitate further placement. 
g. 	With the balloon inflated, the catheter is “floated” through the right atrium into the right ventricle and ultimately “wedges” into a proximal branch of the pulmonary artery. 
h. 	Once in place, the balloon is deflated to allow blood flow around the catheter.
i. 	Two of the lumens are connected to pressure transducers that continuously display measurements. 
2. 	Thermistor
a. 	A thermistor used for thermodilution CO measurement is connected to the distal end of the PAC. 
b. 	The thermistor provides continuous reading of pulmonary artery temperature, which is the best indicator of core body temperature.
3. 	Indications
a. 	A PAC may be when clinicians have a specific question about a patient’s hemodynamic status that has not or cannot be answered readily by noninvasive assessment. 
b. 	Indications
i. 	Differentiation among causes of shock
ii. 	Determining mechanisms responsible for pulmonary edema
iii. 	Diagnosis or detection of pericardial tamponade
iv. 	Evaluation or diagnosis of intracardiac shunt(s)
v. 	Evaluation of pulmonary hypertension
vi. 	Perioperative and postoperative management of patients with unstable cardiac status
vii. 	Management of complex myocardial infarction
viii. Management of patients undergoing cardiac and major vascular surgery
ix. 	Guidance for titration of inotropic, vasopressor, or vasodilator therapy
x. 	Management of severe preeclampsia
xi. 	Fluid volume status management
xii. 	Assessment of cardiac performance
4. 	Contraindications
a. 	Significant coagulopathy
b. 	Local trauma to the site of insertion
c. 	Infection at the site of insertion
d. 	Inability to float the PAC into the pulmonary artery
5. 	Complications
a. 	The greatest potential complication of PAC use is misinterpretation of the data by clinicians.	
b. 	Other complications include those associated with central line insertion and pulmonary artery perforation or rupture, pulmonary infarction, arrhythmias, tricuspid and pulmonic valve injury, and tamponade. 

IV. Invasive Pressure Measurements
	Time: 44 Minutes
	Slides: 40–68
	Lecture/Discussion
A. 	Common hemodynamic parameters and how they are obtained
1. 	Central venous pressure (central line or PAC)
2. 	Systemic blood pressure (arterial line)
3. 	DBP (arterial line)
4. 	MAP (arterial line, calculated or computed)
5. 	Pulse pressure (arterial line, calculated)
6. 	Pulmonary artery pressure (systolic, diastolic, and mean) (PAC)
7. 	PCWP (PAC)
8. 	CO (PAC)
9. 	Pulmonary vascular resistance (PAC, calculated)
10. 	SVR (PAC, calculated)
11. 	Stroke volume (PAC, calculated)
12. 	Mixed venous oxygen saturation (PAC)
13. 	Total body surface area
14. 	Cardiac index (PAC, calculated)
B. 	Cardiovascular physiology
1. 	Cardiac output (CO)
a. 	CO is the product of stroke volume (SV) and heart rate. (CO = SV  Heart Rate). 
b. 	SV is determined by preload, afterload, and contractility of the heart. 
2. 	Preload
a. 	Preload is the degree of myocardial fiber stretch induced by volume in the ventricle at the end of diastole. 
b. 	Preload is synonymous with end-diastolic volume and end-diastolic pressure.
c. 	Preload is determined by total blood volume, blood volume distribution, and atrial kick. 
d. 	States of hypovolemia result in decreased preload and may result from hemorrhage, diaphoresis, protracted vomiting or diarrhea, dehydration, burns, gastric suction, and other causes. 
e. 	Hypervolemia, which typically results from fluid overload as a result of overzealous or runaway IV fluid administration or renal failure, is reflected in increased preload. 
f. 	Right ventricular preload is measured by CVP, which is closely synonymous with RA pressure. 
g. 	Left ventricular preload is measured by PCWP or, in some patients, by pulmonary artery diastolic pressure. 
3. 	Afterload
a. 	Afterload is the resistance the ventricles must overcome to eject blood. 
b. 	Three factors typically determine afterload: outflow obstructions, vascular tone, and blood viscosity. 
c. 	Left ventricular afterload is measured by SVR, and right ventricular afterload is measured by PVR. 
d. 	Left ventricular afterload is evaluated when addressing issues with CO because manipulations of SVR affect systemic circulation. 
e. 	Right ventricular afterload is evaluated when trying to discover a correlation between pulmonary artery diastolic pressure and PCWP and when evaluating a patient for a heart transplant. 
4. 	Contractility
a. 	Contractility is the force with which the heart muscle contracts. 
b. 	Contractility is not directly measurable using conventional hemodynamic monitoring.
c. 	Factors that influence contractility include myocardial muscle health, autonomic nervous system, metabolic states, ion environment, pharmacologic agents, and heart rate.
d.  	Myocardial muscle injury or ischemia can decrease contractility.
e. 	Multiple pharmacologic agents influence myocardial contractility, including digoxin, dopamine, dobutamine, milrinone, calcium, epinephrine, and glucagon.
f. 	Negative inotropic agents, or those that decrease contractility, include beta-blockers, quinidine, procainamide, and calcium channel blockers. 
g. 	Heart rate can influence contractility by its effect on diastolic filling time and coronary artery perfusion. 
h. 	Contractility is inferred from the values for stroke volume index, left ventricular stroke work index, and right ventricular stroke work index.
C. 	Measurements from a central venous line
1. 	Central venous pressure (CVP)
a. 	CVP is a measure of the vena caval and RA pressures. 
b. 	It measures the RA filling pressures and is, therefore, indicative of the patient’s fluid volume status and right-sided heart performance. 
c. 	The CVP can be measured by using a central line or the proximal port of a PAC. 
d. 	Changes in the CVP generally correlate with changes in left ventricular filling pressure in healthy people. 
e. 	The normal range for the CVP is 2 to 6 mm Hg.
f. 	Lower CVP values can indicate hypovolemia or significant vasodilation.
g. 	Elevated CVP readings can result from positive-pressure ventilation, increased PVR, hypervolemia, right-sided heart failure, cardiac tamponade, tricuspid insufficiency, significant vasoconstriction, pulmonary embolus or obstructive pulmonary disease, and left ventricular failure.
D. 	Measurements from an arterial line
1. 	Arterial blood pressure
a. 	Using an arterial line to measure blood pressure provides continuous assessment of arterial (or systemic) pressure. 
b. 	An arterial line provides constantly updated SBP, DBP, and MAP values and an arterial waveform.
c. 	Components of the arterial waveform include the dicrotic notch, mean pressure, systole, diastole, systolic pulse pressure, and diastolic pulse pressure. 		
d. 	Blood pressure readings from an arterial catheter have less potential for error.
2. 	Mean arterial pressure (MAP)
a. 	The MAP represents the average pressure the arterial vasculature feels from the heartbeat. 
b. 	The MAP is unaffected by the location of line placement and is the best parameter to use when making treatment decisions. 
c. 	A person needs an MAP between 70 and 105 mm Hg. 
3. 	Pulse pressure
a. 	Pulse pressure is calculated by using the SBP and DBP. 
b. 	It is the mathematical difference between the SBP and DBP.
c. 	Normal values are 40 to 60 mm Hg 
E. 	Measurements from a PAC
1. 	Right ventricular pressure
a.  	Normal right ventricular pressure during insertion and use of a PAC 		
i. 	Systolic pressure: 20 to 30 mm Hg
ii. 	Diastolic pressure: 0 to 5 mm Hg
iii. 	Mean pressure: 10 to 20 mm Hg
b. 	Ventricular ectopy is common when the PAC is in the right ventricle.
c. 	It is important for CCTP to be able to recognize a right ventricular waveform and its characteristic low diastolic pressure,
2. 	Pulmonary artery pressure
a. 	Pulmonary artery pressures are a function of right ventricular health and the vascular resistance of the pulmonary circuit.
i. 	Systolic pressure: 15 to 30 mm Hg
ii. 	Diastolic pressure: 8 to 15 mm Hg
iii. 	Mean pulmonary artery pressure: 10 to 20 mm Hg
b. 	CCTP who observe a sudden elevation in pulmonary artery pressures will immediately assess and correct any issues with oxygen saturation or ventilation. 	
c. 	If pulmonary artery diastolic pressures suddenly drop, the catheter position should be reevaluated to determine if the PAC has migrated into the right ventricle. 
3. 	Pulmonary capillary wedge pressure (PCWP)
a. 	The PCWP reflects preload to the left ventricle and is the gold standard for preload assessment. 
b. 	The normal range for the PCWP is 4 to 12 mm Hg. 
c. 	Hemodynamic waveforms often show variations in the baseline as a result of respiratory-induced intrathoracic pressure fluctuations. 
d. 	End expiration in spontaneously breathing patients is found at the peak of the waveform baseline.
e. 	In mechanically ventilated patients, end expiration is found in the valley of the waveform baseline.
f. 	If a patient has pulmonary edema, CCTP may use the PCWP to aid in finding the cause. 
F. 	The Frank-Starling law
1. 	Introduction
a. 	There is a relationship between the distention of the ventricular myocardium and the force of the contraction. 
b. 	As ventricular preload increases, the force of contraction of the myocardium also increases. 
c. 	This relationship continues until a point is reached, and then the force of contraction begins to fall off with subsequent detrimental increases in preload.
2. 	Cardiac output (CO)
a. 	CO is an intermittent assessment that involves some action by CCTP.
b. 	Typical CO assessment using a PAC uses the thermodilution method. 
3. 	Fick principle
a. 	This method for calculating CO was adopted by Adolph Fick in 1870.
b. 	This method divides oxygen consumption by the difference between oxygen content of arterial and venous blood. 
c. 	The formula uses assumed values for oxygen consumption derived from basal metabolic studies on healthy subjects, which may or may not be valid in critically ill patients. 
4. 	Pulmonary vascular resistance (PVR)
a. 	The PVR represents the resistance of the pulmonary vascular circuit that flows out of the right ventricle and pulmonary artery.
b. 	It is also called right-sided heart overload.
c. 	CCTP may see an elevated PVR in patients with pulmonary hypertension or mitral valve stenosis.
5. 	Systemic vascular resistance (SVR)
a. 	SVR represents the total impedance to blood flow felt by the left ventricle, commonly referred to as afterload. 
b. 	Calculation of the SVR is useful in helping to determine the cause of shock.	
6. 	Stroke volume (SV)
a. 	SV is the amount of blood ejected in each stroke of a ventricle. 
b. 	A normal SV is 60 to 100 mL/beat. 
c. 	Ventricular performance is affected by the contractility of the heart muscle and the preload and afterload to the respective ventricle. 
7. 	Mixed venous oxygen saturation
a. 	If a fiberoptic oxygen saturation probe is attached to the distal end of the PAC, a mixed venous oxygen saturation (SvO2) measurement can be recorded. 
b. 	This measurement is constant and requires no action by the clinician once the catheter is placed. 
c. 	SvO2 reflects the global balance between oxygen delivery and consumption. 
d. 	A measurement similar to mixed venous oxygen saturation is the mixed central venous oxygen saturation (ScvO2).
i. 	Measurements of ScvO2 are obtained from a central venous catheter by drawing a blood gas specimen or from a fiberoptic oximetric tip connected to a specially designed monitor that displays the oxygen saturation. 

V. Obtaining Invasive Hemodynamic Measurements
	Time: 15 Minutes
	Slides: 69–78
	Lecture/Discussion
A. 	Introduction
1. 	Once placed, the catheter is connected to a pressure-monitoring transducer by using rigid pressure-monitoring tubing. 
2. 	Once the monitoring system is connected to the patient, the pressure bag is inflated to 300 mm Hg, or above the patient’s BP. 
3. 	Whenever the pressure in the monitoring system exceeds the patient’s BP, each transducer will flow 3 mL/h of flush solution into the patient. 
4. 	This continuous flush system maintains catheter patency and prevents blood backflow into the catheter and monitoring system. 
5. 	If the transfer will involve air medical transport, all of the air should be expelled to prevent expansion during flight.
6. 	Proper setting of monitoring alarms is the best protection against dislodging or other problems.
B. 	Leveling and zeroing the pressure transducer
1. 	The most common cause of error in obtaining direct hemodynamic pressure measurements is incorrect leveling of the transducer.
2. 	Fluid used to fill the pressure tubing that connects the monitoring catheter between the patient and the transducer will interfere with pressure readings if the pressure transducer is lower or higher than mid-heart level. 
3. 	Referencing is the process of ensuring that the hemodynamic pressure transducer is at the level of the left atrium. 
4. 	The transducer must be releveled with every position change of the patient.
5. 	The simplest way to ensure proper placement during transport is to secure the transducer at the phlebostatic axis.  
6. 	Leveling should be performed with a carpenter’s level or leveling tool designed for hemodynamic monitoring applications.
7. 	Any pressure transducer must be “zeroed” to eliminate the effects of atmospheric pressure on the measurements obtained. 
C. 	Respiratory variations
1. 	Changes in intrathoracic pressure result in variable direct pressure measurements. 
2. 	To accurately obtain measurements, it is important to take readings at end expiration. 
3. 	In mechanically ventilated patients, end expiration occurs in the lower portions, or valleys, of the rise-and-fall pattern. 
4. 	End expiration in spontaneously breathing patients correlates to the peaks of the rise-and-fall pattern. 
D. 	Transducers and cables
1. 	CCTP should become familiar with transport monitors and the cables needed to connect to pressure-monitoring equipment and transducers. 
2. 	The cables that connect patient transducers to the monitor that an agency uses must be compatible with the equipment in use at the referring and receiving hospitals. 
E. 	Potential complications during transport
1. 	The most common complication is accidental dislodgement or removal of the line or catheter. 	
2. 	If an invasive line comes completely out of a patient, CCTP should immediately apply direct pressure to the insertion site and hold it until bleeding stops.
3. 	No attempt should be made to replace a catheter that dislodges but does not come completely out of the patient.
4. 	A catheter that needs to be removed is gently withdrawn from the patient, and efforts are made to stop any bleeding.

VI. Recognition of Shock
	Time: 11 Minutes
	Slides: 79–85
	Lecture/Discussion
A. 	Hemodynamic monitoring can help CCTP to differentiate between various types of shock and assess the effectiveness of treatment during transport. 
B. 	Types of shock
1. 	Hypovolemic shock includes:
a.	Volume loss from acute or chronic hemorrhage
b.	Excessive diuresis
c.	Third-space losses
d.	Any other condition that depletes intravascular volume
2. 	Cardiogenic shock has many causes that include:
a.	Myocardial depression from ischemia and/or infarcts
b.	Cardiomyopathies
c.	Stunning following cardiac surgery
d.	Arrhythmias
e.	Mechanical abnormalities
f.	Massive pulmonary embolism
g.	Tension pneumothorax
h.	Pericardial tamponade
3. 	Distributive shock states include:
a.	Sepsis
b.	Systemic inflammatory response syndrome
c.	Toxic shock syndrome
d.	Anaphylaxis
e.	Poisonings
f.	Neurogenic conditions
g.	Other vasodilatory etiologies. 
C. 	Prompt recognition and reversal of shock avoids cell death, end-organ damage, lactic acidosis, multisystem organ failure, and death.
D. 	CO and SVR can be used to identify different types of shock. 
1. 	In hypovolemic shock, preload is decreased due to depleted intravascular volume. Decreased preload leads to a decline in SV, which results in decreased CO.
2. 	Cardiogenic shock involves a cascade of events resulting from pump failure leading to decreased CO. 
a.	The SVR increases in an effort to maintain CO, which exacerbates pump failure and leads to increased preload and a relative total hypervolemic condition. 
3. 	In distributive shock, vasodilation is observed 	by a significantly decreased SVR. When afterload declines dramatically, CO increases.

VII. Flight Considerations
	Time: 3 Minutes
	Slides: 86–87
	Lecture/Discussion
A.  	Monitoring oxygen saturation will enable CCTP to respond to changes in a patient’s condition. 
B. 	Physiologic changes include a chemoreceptor-induced increase in tidal volume and an increased CO.
C. 	Air should be removed from IV bags because it will expand.
D. 	Pumps should be used for medication infusions. 
E. 	Zeroing of transducers is recommended when cruising altitude is reached and with changes of altitude of 1,000’ or more.