Physiological Monitoring of the Surgical Patient

Question 1

Hemodynamic Monitoring purposes

4

Answer 1

1. Provides information as to the CP status of the patient
2. Traditional clinical assessments are usually unreliable
3. Major changes in the cardiovascular status may not be clinically obvious
4. Invasive techniques must be utilized

Question 2

Hemodynamic Monitoring

A. Arterial Catheterization (“ART Line”) indications? 2

Answer 2

1. Need for continuous blood pressure monitoring

2. Need for frequent arterial blood sampling

Question 3

Hemodynamic Monitoring
Arterial Catheterization
Conditions that need continuous and accurate BP monitoring? 6

Answer 3

1. Shock states
2. Hypertensive crisis
3. Surgery in high risk patients
4. Use of potent vasoactive or inotropic drugs
5. Controlled hypotensive anesthesia
6. Situations that may lead to rapid changes in cardiac function

Question 4

Hemodynamic Monitoring
Arterial Catheterization
Contraindications
1. Absolute? 1
2. Relative? 4

Answer 4

Contraindications
1. No ABSOLUTE contraindication to arterial catheterization

2. RELATIVE contraindications are:
   a. Bleeding problems (hemophilia)
   b. Anticoagulant therapy
   c. Presence of a vascular prosthesis
   d. Local infection

Question 5

Hemodynamic Monitoring
Arterial Catheterization
Sites for catheterization? 6

Answer 5

1. radial artery
2. axillary artery
3. femoral artery
4. dorsalis pedis artery
5. superficial femoral artery
6. brachial artery

Question 6

Hemodynamic Monitoring
Sites for Catheterization
whats the most commonly used site?

Answer 6

Radial artery

Question 7

Radial artery: Why do we used this site commonly for arterial cath? 3

Monitoring before insertion and during? 4

Answer 7

1. Duel blood supply
2. simple canulation
3. low complication rate
4. modified “Allen’s” test – assess ulnar artery
5. Doppler technique,
6. plethysmography, 4. pulse oximetry

Question 8

Sites for Catheterization
Axillary artery:
1. Used for what?
2. Size?
3. Location? 2
4. Technical difficulty with this?
5. Located near what?

Answer 8

1. for long term monitoring
2. large size
3. • close proximity to the aorta
   • deep location
4. technical difficulty in insertion
5. located near neurovascular structures

Question 9

Sites for Catheterization
Femoral artery:
1. Size and location?
2. Prone to what?
3. Difficulty?

Answer 9

1. large size and superficial location
2. prone to atherosclerosis
3. difficult to keep clean

Question 10

Sites for Catheterization
Superficial temporal artery:
1. Whats required for this? 1
2. Complication observed? 1

Answer 10

1. surgical exposure is required

2. neurologic complications observed

Question 11

1. Which cath site is used for short term only?

2. Greatest risk with this?

Answer 11

1. brachial artery

2. risk of median nerve contracture (Volkman’s contracture)

Question 12

Arterial Catheterization

Complications of arterial catheterization? 7

Answer 12

1. failure to cannulate
2. hematoma
3. disconnection from monitoring system
4. Infection
5. retrograde cerebral embolization
6. A-V fistula / pseudoaneurysm
7. severe pain, distal necrosis

Question 13

What things make infection more likely for arterial cath? 3

Answer 13

1. catheters in place for more than 4 days
2. surgical insertion
3. local inflammation

Question 14

1. Central venous pressure… a direct measurement of what?
2. It is acquired by threading a central venous catheter where?
3. Threaded so that the tip of the catheter rests where? The pressure monitoring assembly is attached to the distal port of a multilumen central vein catheter.

Answer 14

1. the blood pressure in the right atrium and vena cava.
2. (subclavian double lumen central line) into any of several large veins.
3. in the lower thirdof the superior vena cava

Question 15

1. In seriously ill patients the vital problem is determination of the proper amount of fluids
   and blood requirements necessary to MAINTAIN an optimal blood volume in the what? 3

Answer 15

1. Preoperative
2. Operative
3. Postoperative

Question 16

Hemodynamic Monitoring
1. Central Venous Pressure Monitoring is a reliable procedure to evaluate what?

2. The procedure removes much of the guess work in rapid restoration and maintenance of adequate circulation w/o fear of what?

Answer 16

1. properly and promptly optimal fluid and blood requirement in these patients.
2. overloading the heart

Question 17

Central Venous Pressure Monitoring
Sites of catheterization
1. What is the easiest to cannulate?
2. Most common complication?
3. Difficulty?

Answer 17

1. Subclavian vein
2. pneumothorax most common complication
3. difficult to control bleeding

Question 18

Central Venous Pressure Monitoring
Sites of catheterization
1. Which has the lowest risk of pneumothorax?
2. Most common complication?

Answer 18

1. internal jugular vein

2. arterial puncture most common complication

Question 19

Central Venous Pressure Monitoring
1. CVP measured anywhere in the what or their immediate tributaries»>Innominate, and the Common Iliac Veins? 2

2. It is determined by a complex interaction of? 3
3. Serves as index of what relative to the Cardiac Pump Action?

Answer 19

1. Superior VC or Inferior VC
2. • Blood Volume
   • Cardiac Pump Action
   • Vascular Tone
3. circulating blood volume

Question 20

Central Venous Pressure Monitoring
1. CVP or the pressure in the Right Atrium & adjacent Caval system will reflect ability of the Cardiac Pump Action to handle the what?

2. Indications? 5

Answer 20

1. returning blood volume at that particular time.
2. • When Massive blood replacement is instituted rapidly in rapid exsanguinating type of bleeding.

• In Acute blood volume deficit in cases operated for strangulating type of Intestinal
  Obstruction where rapid fluid replacement is indicated
• In obscure cases of Shock immediately post-op whether hypovolemic due to internal
  bleeding or nonhypovolemic from Myocardial Infarction.
• In elderly patients with limited cardiac reserve undergoing difficult, time consuming operations.
• In surgical patients with anuria due to possible renal shutdown.

Question 21

Central Venous Pressure Monitoring
Basic Facts about CVP.
1. Normal CVP is about ______?

2. Low CVP is what levels and indicates what?
3. High CVP is what?

Answer 21

1. 4 to 7 cm
2. 0-3 indicates circulating blood volume is below the normal blood volume the
   heart can handle.
3. 8-20 (more than the heart can handle)

Question 22

Central Venous Catheterization
Indications:

7

Answer 22

1. access for fluid therapy
2. access for drug infusion
3. parenteral nutrition
4. CVP monitoring
5. aspirate air embolism
6. placement of cardiac pacemaker / vena cava filters
7. hemodialysis access

Question 23

Central Venous Catheterization

1. Useful in what pts?
2. Tracings for?
3. Gives information about the relationship between what?
4. Use what for pressure measurements?
5. Normal CVP measurement?

Answer 23

1. Useful in hypotensive patients
2. Tracings for arrhythmias
3. Gives information about the relationship between intravascular volume and right
   ventricular function
4. Use of a water manometer for pressure measurements
5. Normal CVP measurement 4-7 mmH2O

Question 24

Central Venous Pressure Monitoring

• Technique
  1. Cannulation of the Superior Vena Cava through what? 2

2. A polyethelene tube size what inches long is inserted at the Basilic Vein
3. just above the where and pushed up to where?
4. Connect an Intravenous administration set to the venous catheter in order to?
5. A _________ is connected to IV set w/ a three way stopcock.
6. Zero point should be at
   level of the what? 2

Answer 24

1. Basilic or Cephalic Veins.
2. French 8 and 42
3. elbow and pushed up to 20 inches.
4. through which IV fluid may be administered.
5. Manometer
6. atrium or approximately at Mid-axillary line

Question 25

Swan-Ganz Pulmonary Artery Catheter 1. Pulmonary artery catheterization (PAC) is the insertion of a catheter into the what? 2. Whats its purpose? 3. Used to detect? 4 4. Allows direct, simultaneous measurement of pressures in what? 4

Answer 25

1. pulmonary artery. 2. Its purpose is diagnostic 3. Used to detect - heart failure, - sepsis, - monitor therapy, and - evaluate the effects of drugs. 4. Allows direct, simultaneous measurement of pressures in: - the right atrium - right ventricle - pulmonary artery - filling pressure ("wedge" pressure) of the left atrium.

Question 26

General indications for PAC? | 8

Answer 26

1. Management of complicated myocardial infarction 2. Assessment of respiratory distress 3. Assessment of type of shock 4. Assessment of therapy 5. Assessment of fluid requirement in critically ill patients 6. Management of postoperative open heart surgical patients 7. Assessment of valvular heart disease 8. Assessment of cardiac tamponade/constriction

Question 27

PAC 1. Management of complicated myocardial infarction such as? 6 2. Assessment of respiratory distress: specifically? 2 3. Assessment of therapy: such as? 4 4. Assessment of fluid requirement in critically ill patients: What are we assessing for? 4

Answer 27

1. - Hypovolemia vs cardiogenic shock - Ventricular septal rupture (VSR) vs acute mitral regurgitation - Severe left ventricular failure - Right ventricular infarction - Unstable angina - Refractory ventricular tachycardia 2. - Cardiogenic vs non-cardiogenic pulmonary edema - Primary vs secondary pulmonary hypertension 3. - Afterload reduction - Vasopressors - Beta blockers - Intra-aortic balloon counter-pulsation 4. - Hemorrhage - Sepsis - Acute renal failure aka Acute Kidney Injury - Burns

Question 28

The PAC is inserted percutaneously into a what via an introducer sheath? 1 Preference considerations for cannulation of the great veins are as follows? 3

Answer 28

1. major vein (jugular, subclavian, femoral) 1. Right internal jugular vein (RIJ) 2. Left subclavian 3. Femoral veins

Question 29

Describe the advantages of the following: 1. Right internal jugular vein (RIJ)? 1 2. Left subclavian? 1 3. Femoral veins? 1 4. Disadvantages for femoral? 2

Answer 29

1. Shortest and straightest path to the heart 2. - Does not require the PAC to pass and course at an acute angle to enter the SVC (compared to the right subclavian or left internal jugular [LIJ]) 3. Nevertheless, these sites are compressible and may be preferable if the risk of hemorrhage is high. 4. - These access points are distant sites, from which passing a PAC into the heart can be difficult, especially if the right-sided cardiac chambers are enlarged. - Often, fluoroscopic assistance is necessary.

Question 30

CVP Monitoring Complications 5

Answer 30

1. catheter malposition 2. dysrythmmias 3. embolization 4. vascular injury 5. cardiac, pleural, mediastinal, neurologic injury

Question 31

Respiratory Monitoring Monitoring ventilation and gas exchange * Indications? 4

Answer 31

1. Decision making for the need of mechanical ventilation. 2. Assessment of response to therapy. 3. Optimize ventilatory management. 4. Decision to wean from ventilator.

Question 32

Monitoring ventilation and gas exchange | Ventilation monitoring: What does it measure and describe what it is? 4

Answer 32

1. Tidal volume – volume of air moved in or out of the lung in a single breath 2. Vital capacity – maximal volume at expiration after a maximal inspiration 3. Minute volume – total volume of air leaving the lung each minute 4. Physiologic dead space – the portion of tidal volume that does not participate in in gas exchange a. anatomic dead space

Question 33

Monitoring ventilation and gas exchange Ventilation monitoring Physiologic dead space – the portion of tidal volume that does not participate in in gas exchange What are the two kinds of dead space?

Answer 33

a. anatomic dead space | b. physiologic dead space

Question 34

``` Monitoring ventilation and gas exchange Gas Monitoring 1. Reported as directly measured what? 2. Use of what for continuous measurements? ``` 3. Blood gas analysis – information about what? 3

Answer 34

1. partial pressures (PO2 and PCO2) 2. pulse oximeters 3. a. efficacy of gas exchange b. adequacy of alveolar ventilation c. acid–base status

Question 35

Monitoring ventilation and gas exchange Gas Monitoring 1. What is Capnography? 2. What are the different forms we can measure this in? 5

Answer 35

1. graphic display of CO2 concentration in wave form 2. a. infrared analysis b. mass spectrometry c. Raman scattering d. disposable colorimetric devices e. semi-quantitive measurement on the end- tidal CO2 concentration

Question 36

Gas Monitoring Pulse oximetry 1. reliable, real time estimation of the what?

Answer 36

1. arterial Hgb saturation | - wide clinical acceptance

Question 37

Monitoring ventilation and gas exchange Gas Monitoring 1. Gastric Tonometry is what?

Answer 37

relatvely non-invasive monitoring of adequacy of aerobic metabolism in organs whose superficial mucosal lining is extremely vulnerable to low flow changes and hypoxemia

Question 38

Renal monitoring: 1. The kidney is an excellent monitor of what? 2. Prevention of what? 3. Predict what?

Answer 38

1. adequacy of perfusion 2. renal failure 3. drug clearance and proper dose adjustment

Question 39

``` Renal monitoring: Urine Output 1. Commonly monitored but? 2. Normal urine output? 3. Correlates with what? 4. High output may not accuraltely refelct what? ```

Answer 39

1. Commonly monitored but may be misleading 2. Normal urine output → 0.5 ml/kg/hour 3. Correlates with glomerular filtration rate (GFR) 4. High output may not accurately reflect GFR ex. Diabetes Insipidus

Question 40

1. What is the most common type of indwelling urinary catheter?

Answer 40

1. A Foley catheter is a flexible tube passed through the urethra and into the bladder to drain urine.

Question 41

1. The tube of a Foley catheter has two separated lumens, running down its length. One lumen is open at both ends, and drains where? 2. The other lumen has a valve on the outside end and connects to a what? The balloon is inflated with sterile water when it lies inside the bladder to stop it from slipping out. Commonly made from silicone rubber or natural rubber. Should be used only when indicated, as use increases the risk of catheter-associated urinary tract infections

Answer 41

1. urine into a collection bag | 2. a balloon at the tip.

Question 42

Glomerular Function Tests?

Answer 42

1. Blood Urea Nitrogen (BUN) 2. Plasma Creatinine 3. Creatinine Clearance

Question 43

``` GFR tests: Blood Urea Nitrogen (BUN) 1. Affected by what? 2 2. When is it increased? 5 3. Lowered in what? 2 ``` ``` Plasma Creatinine 1. Describe its accuracy compared to BUN? 2. Directly proportional to what? 3. Inversely related to? 4. Not affected by what? 3 5 Related to? ``` Creatinine Clearance 1. Used when? 2. Describe its reliability?

Answer 43

1. Affected by GFR and urea production 2. Increased in - TPN, - GI bleeding, - trauma, - sepsis, - steroid use 3. Lowered in - starvation, - liver disease 1. More accurate than BUN 2. Directly proportional to creatinine production 3. Inversely related to GFR 4. Not affected by - protein or - nitrogen production or - rate of fluid flow through tubules 5. Related to muscle mass 1. used if values of plasma creatinine are affected by muscle disease 2. serial determination of urine is done and is currently the most reliable method of assessing GFR

Question 44

Renal Monitoring: 1. What is The most reliable test to distinguish pre-renal azotemia from tubular necrosis? 2. Requires what?

Answer 44

1. Tubular funciton tests | 2. Requires simultaneous collected urine and blood samples

Question 45

Neurologic Monitoring…key points | 2

Answer 45

-Early recognition of cerebral dysfunction -Facilitate prompt intervention and treatment

Question 46

A. Intracranial Pressure Monitoring | 2

Answer 46

1. Cerebral Perfusion Pressure >70mmHg | 2. Glasgow Coma Scale

Question 47

Electrophysiologic Monitoring | 1. Reflects what?

Answer 47

spontaneous and on-going electrical activity in the brain

Question 48

Trans-cranial Ultrasound used for what? 2

Answer 48

- Monitors cerebral blood flow | - Detects vasospasm

Question 49

Jugular Venous Oximetry | Measures what?

Answer 49

Measures relationship of blood flow to O2 consumption

Question 50

Metabolic Monitoring…key points | 2

Answer 50

1. Caloric Demands | 2. Respiratory Quotient of Food

Question 51

Temperature Monitoring…key points | 3

Answer 51

A. Rectal B. Middle Ear C. Esophageal