Interpreting ABGs (or the ABCs of ABGs) Suneel Kumar MD

Interpreting ABGsInterpreting ABGs(or the ABCs of ABGs)(or the ABCs of ABGs)

Interpreting ABGsInterpreting ABGs(or the ABCs of ABGs)(or the ABCs of ABGs)

Suneel Kumar MDSuneel Kumar MD

Arterial Blood Gases• Written in following manner:

pH/PaCO2/PaO2/HCO3

– pH = arterial blood pH

– PaCO2 = arterial pressure of CO2

– PaO2 = arterial pressure of O2

– HCO3 = serum bicarbonate concentration

Oxygenation• Hypoxia: reduced oxygen

pressure in the alveolus (i.e. PAO2)

• Hypoxemia: reduced oxygen pressure in arterial blood (i.e. PaO2)

Hypoxia with Low PaO2

• Alveolar diffusion impairment

• Decreased alveolar PO2

– Decreased FiO2

– Hypoventilation– High altitude

• R L shunt• V/Q mismatch

Hypoxia with Normal PaO2

• Alterations in hemoglobin– Anemic hypoxia– Carbon monoxide poisoning– Methemoglobinemia

• Histotoxic hypoxia– Cyanide

• Hypoperfusion hypoxia or stagnant hypoxia

Alveolar—Arterial Gradient

• Indirect measurement of V/Q abnormalities

• Normal A-a gradient is 10 mmHg• Rises with age• Rises by 5-7 mmHg for every 0.10

rise in FiO2, from loss of hypoxic vasoconstriction in the lungs

Alveolar—Arterial Gradient

A-a gradient = PAO2 – PaO2

• PAO2 = alveolar PO2 (calculated)

• PaO2 = arterial PO2 (measured)

Alveolar—Arterial Gradient

PAO2 = PIO2 – (PaCO2/RQ)

• PAO2 = alveolar PO2

• PIO2 = PO2 in inspired gas

• PaCO2 = arterial PCO2

• RQ = respiratory quotient

Alveolar—Arterial Gradient

PIO2 = FiO2 (PB – PH2O)• PB = barometric pressure (760 mmHg)• PH2O = partial pressure of water vapor

(47 mmHg)

RQ = VCO2/VO2

• RQ defines the exchange of O2 and CO2 across the alveolar-capillary interface (0.8)

Alveolar—Arterial Gradient

PAO2 = FiO2 (PB – PH2O) – (PaCO2/RQ)

Or

PAO2 = FiO2 (713) – (PaCO2/0.8)

Alveolar—Arterial Gradient

• For room air:PAO2 = 150 – (PaCO2/0.8)

• And assume a normal PaCO2 (40):

PAO2 = 100

Acid-Base

• Acidosis or alkalosis: any disorder that causes an alteration in pH

• Acidemia or alkalemia: alteration in blood pH; may be result of one or more disorders.

Six Simple Steps1. Is there acidemia or alkalemia?2. Is the primary disturbance respiratory

or metabolic?3. Is the respiratory problem acute or

chronic?4. For metabolic, what is the anion gap?5. Are there any other processes in

anion gap acidosis?6. Is the respiratory compensation

adequate?

Henderson-Hasselbach Equation

pH = pK + log [HCO3/PaCO2] x K(K = dissociation constant of CO2)

Or

[H+] = 24 x PaCO2/HCO3

Henderson-Hasselbach Equation

pH7.207.307.407.507.60

[H+]6050403020

Step 1:Acidemia or Alkalemia?

• Normal arterial pH is 7.40 ± 0.02– pH < 7.38 acidemia– pH > 7.42 alkalemia

Step 2:Primary Disturbance

• Anything that alters HCO3 is a metabolic process

• Anything that alters PaCO2 is a respiratory process

Step 2:Primary Disturbance

• If pH, there is either PaCO2 or HCO3

• If pH, there is either PaCO2 or HCO3

Step 3:Respiratory

Acute/Chronic?• Acute:

CO2 by 10 pH by 0.08

• Chronic:CO2 by 10 pH by 0.03

• Changes in CO2 and pH are in opposite directions

Step 4:For Metabolic, Anion Gap?

Anion gap = Na+ - (Cl- + HCO3-)

– Normal is < 12

Increased Anion Gap• Ingestion of drugs or toxins

– Ethanol– Methanol– Ethylene glycol– Paraldehyde– Toluene– Ammonium chloride– Salicylates

Increased Anion Gap• Ketoacidosis

– DKA– Alcoholic– Starvation

• Lactic acidosis• Renal failure

Step 4:For Metabolic, Anion

Gap?

• If + AG, calculate Osm gap:

Calc Osm = (2 x Na+) + (glucose/18) + (BUN/2.8) + (EtOH/4.6)

Osm gap = measured Osm – calc Osm

Normal < 10 mOsm/kg

Nongap Metabolic Acidosis

• Administration of acid or acid-producing substances– Hyperalimentation– Nonbicarbonate-containing IVF

Nongap Metabolic Acidosis

• GI loss of HCO3

– Diarrhea– Pancreatic fistulas

• Renal loss of HCO3

– Distal (type I) RTA– Distal (type IV) RTA– Proximal (type II) RTA

Nongap Metabolic Acidosis

• Calculate urine anion gap:Urine AG = (Na+ + K+) – Cl-

– Positive gap indicates renal impaired NH4

+ excretion

– Negative gap indicates normal NH4+

excretion and nonrenal cause

Nongap Metabolic Acidosis

• Urine Cl- < 10 mEq/l is chloride responsive and accompanied by “contraction alkalosis” and is “saline responsive”

• Urine Cl- > 20 mEq/l is chloride resistant, and treatment is aimed at underlying disorder

Step 5: Any other process with elevated

AG?• Calculate gap, or “gap-gap”:

Gap = Measured AG – Normal AG (12)

Step 5: Any other process with elevated

AG?• Add gap to measured HCO3

– If normal (22-26), no other metabolic problems

– If < 22, then concomitant metabolic acidosis

– If > 26, then concomitant metabolic alkalosis

Step 6: Adequate respiratory

compensation?Winter’s Formula

Expected PaCO2 = (1.5 x HCO3) + 8 ± 2

– If measured PaCO2 is higher, then concomitant respiratory acidosis

– If measured PaCO2 is lower, then concomitant respiratory alkalosis

Step 6: Adequate respiratory

compensation?• In metabolic alkalosis, Winter’s

formula does not predict the respiratory response– PaCO2 will rise > 40 mmHg, but not

exceed 50-55 mmHg– For respiratory compensation, pH will

remain > 7.42

Clues to a Mixed Disorder

• Normal pH with abnormal PaCO2 or HCO3

• PaCO2 and HCO3 move in opposite directions

• pH changes in opposite direction for a known primary disorder

Case 1• A 24 year old student on the 6

year undergraduate plan is brought to the ER cyanotic and profoundly weak. His roommate has just returned from a semester in Africa. The patient had been observed admiring his roommate's authentic African blowgun and had scraped his finger on the tip of one of the poison darts (curare).

Case 1

138 10026

7.08/80/37

Case 1• What is the A-a gradient?

A-a gradient = [150 – 80/0.8] - 37A-a gradient = 13

• Acidemia or alkalemia?• Primary respiratory or metabolic?• Acute or chronic?

PCO2 by 40 would pH by 0.32

Case 1• What is the anion gap?

AG = 138 – (100 + 26)AG = 12

Case 1

• Acute respiratory acidosis

Case 2• A 42 year old diabetic female who

has been on insulin since the age of 13 presents with a 4 day history of dysuria which has progressed to severe right flank pain. She has a temperature of 38.8ºC, a WBC of 14,000, and is disoriented.

Case 2

135 99

124.8

7.23/25/113

Case 2• What is the A-a gradient?

A-a = [150 – 25/0.8] – 113 = 6• Acidemia or alkalemia?• Primary respiratory or metabolic?• What is the anion gap?

AG = 135 – (99 + 12) = 24

Case 2• What is the gap?

Gap = 24 – 12 = 12Gap + HCO3 = 12 + 12 = 24

– No other metabolic abnormalities

• Is the respiratory compensation appropriate?Expected PCO2 = (1.5 x 12) + 8 ± 2 =

24 ± 2– It is appropriate

Case 2

• Acute anion gap metabolic acidosis (DKA)

Case 3• A 71 year old male, retired

machinist, is admitted to the ICU with a history of increasing dyspnea, cough, and sputum production. He has a 120 pack-year smoking history, and quit 5 years previously. On exam he is moving minimal air despite using his accessory muscles of respiration. He has acral cyanosis.

Case 3

135 93

30

7.21/75/41

Case 3• What is the A-a gradient?

A-a = [150 – 75/.8] – 41 = 15• Acidemic or alkalemic?• Primary respiratory or metabolic?• Acute or chronic?

– Acute PCO2 by 35 would pH by 0.28

– Chronic PCO2 by 35 would pH by 0.105• Somewhere in between

Case 3• What is the anion gap?

AG = 135 – (93 + 30) = 12

Case 3

• Acute on chronic respiratory acidosis (COPD)

Case 3b• This same patient is intubated and

mechanically ventilated. During the intubation he vomits and aspirates. He is ventilated with an FiO2 of 50%, tidal volumes of 850 mL, PEEP of 5, rate of 10. One hour later his ABG is 7.48/37/215.

Case 3b• Why is he alkalotic with a normal

PCO2?– Chronic compensatory metabolic

alkalosis and acute respiratory alkalosis

Case 4• A 23 year old female presents to

the Emergency Room complaining of chest tightness and light-headedness. Other symptoms include tingling and numbness in her fingertips and around her mouth. Her medications include Xanax and birth control pills, but she recently ran out of both.

Case 4

135 10922

7.54/22/115

Case 4• What is the A-a gradient?

A-a = [150 – 22/.8] – 115 = 8• Acidemia or alkalemia?• Primary respiratory or metabolic?• Acute or chronic?

– Acute CO2 by 18 would pH by 0.144

• What is the anion gap?AG = 135 – (109 + 22) = 4

Case 4

• Acute respiratory alkalosis (panic attack)

Case 5• 72 year old woman admitted from

a nursing home with one week history of diarrhea and fever.

133 1185

7.11/16/94

Case 5• What is the A-a gradient?

A-a = [150 – 16/.8] – 94 = 36• Acidemia or alkalemia?• Primary respiratory or metabolic?• What is the anion gap?

AG = 133 – (118 + 5) = 10• Is respiratory compensation

adequate?PCO2 = (1.5 x 5) + 8 ± 2 = 16 ± 2

Case 5

• Non anion gap metabolic acidosis (diarrhea)

• Compensatory respiratory alkalosis

Case 6

• A 27 year old pregnant alcoholic with IDDM is admitted one week after stopping insulin and beginning a drinking binge. She has experienced severe nausea and vomiting for several days.

Case 6

136 70

19

7.58/21/104

Case 6• What is the A-a gradient?

A-a = [150 – 21/.8] – 104 = 20• Acidemia or alkalemia?• Primary respiratory or metabolic?• What is the anion gap?

AG = 136 – (70 + 19) = 47• What is the gap?

Gap = 47-12 = 35

Gap + HCO3 = 54

Case 6

• Primary respiratory alkalosis (pregnancy)

• Anion gap metabolic acidosos (ketoacidosis)

• Nongap metabolic alkalosis (vomiting)

Case 7• 35 year old male presents to the

ER unconscious.

145 70

23

7.61/24/78

Creat 6.1

Case 7• What is the A-a gradient?

A-a = [150 – 24/.8] – 78 = 42• Acidemia or alkalemia?• Primary respiratory or metabolic?• What is the anion gap?

AG = 145 – (70 + 23) = 52

Case 7

• What is the gap?

Gap = 52 - 12 = 40

Gap + HCO3 = 63–Nongap metabolic alkalosis

Case 7

• Respiratory alkalosis• Anion gap metabolic acidosis

(renal failure)• Nongap metabolic alkalosis

Bonus Case #1

• 51 year old man with polysubstance abuse, presented to ER with 3-4 day h/o N/V and diffuse abdominal pain. Reports no EtOH or cocaine in 2 weeks. He has been taking “a lot” of aspirin for pain. Denies dyspnea, but has been tachypneic since arrival.

Bonus Case #1

• Afebrile, P 89, R 20, BP 142/57. Lethargic but arrousable, easily aggitated. Lungs clear, and abdomen is soft with mild tenderness in LUQ and LLQ.

Bonus Case #1126

3.4

93

11

58

1.8218

UA 1+ ketones

Acetone negative

Lactate 6.9

EtOH 0

Osm 272

7.46/15/107

Bonus Case #1• What is the A-a gradient?

A-a = [150 – 15/.8] – 107 = 25• Acidemia or alkalemia?• Primary respiratory or metabolic?• What is the anion gap?

AG = 126 – (93 + 11) = 22Anion gap metabolic acidosis

Bonus Case #1• What is the gap?

Gap = 22 - 12 = 10

Gap + HCO3 = 21Nongap metabolic acidosis

• What is the osmolar gap?Calc Osm = 2x126 + 218/18 +

58/2.8Calc Osm = 265

Osm gap = 272 – 265 = 7

Bonus Case #1

• Respiratory alkalosis (aspirin)• Anion gap metabolic acidosis

(aspirin)• Nongap metabolic acidosis

Bonus Case # 2

• 20 year old college student brought to the ER by his fraternity brothers because they cannot wake him up. He had been in excellent health until the prior night.

Bonus Case #2

• Afebrile, P 118, R 32, BP 120/70. Anicteric sclerae, pupils 8mm and poorly responsive to light. Fundoscopic exam with slight blurring of discs bilaterally and increased retinal sheen. Remainder of exam unremarkable.

Bonus Case #2142

4.3

98

10

14 108

UA negative

EtOH 45

Osm 348 7.22/24/108

Bonus Case #2• What is the A-a gradient?

A-a = [150 – 24/.8] – 108 = 12• Acidemia or alkalemia?• Primary respiratory or metabolic?• What is the anion gap?

AG = 142 – (98 + 10) = 34Anion gap metabolic acidosis

Bonus Case #2• What is the gap?

Gap = 34 - 12 = 22

Gap + HCO3 = 32

Nongap metabolic alkalosis

Bonus Case #2• What is the osmolar gap?

Calc Osm = 2x142 + 108/18 + 14/2.8 + 45/4.6

Calc Osm = 305Osm gap = 348 - 305 = 43

• Is the respiratory compensation adequate?

PCO2 = (1.5 x 10) + 8 ± 2 = 23 ± 2

Bonus Case #2

• Anion gap metabolic acidosis with elevated osmolar gap (methanol)

• Nongap metabolic alkalosis• Compensatory respiratory

alkalosis

Bonus Case #3

• A 23 year old man presents with confusion. He has had diabetes since age 12, and has been suffering from an intestinal flu for the last 24 hours. He has not been eating much, has vague stomach pain, stopped taking his insulin, and has been vomiting. His glucose is high.

Bonus Case #3

130 80

10

7.20/25/68

Bonus Case #3

• What is the A-a gradient?A-a = [150 – 25/.8] – 68 = 51

• Acidemia or alkalemia?• Primary respiratory or metabolic?• What is the anion gap?

AG = 130 – (80 + 10) = 40Anion gap metabolic acidosis

Bonus Case #3

• What is the gap?

Gap = 40 - 12 = 28

Gap + HCO3 = 38

Nongap metabolic alkalosis

• Is the respiratory compensation adequate?

PCO2 = (1.5 x 10) + 8 ± 2 = 23 ± 2

Bonus Case #3

• Anion gap metabolic acidosis (DKA)

• Metabolic metabolic alkalosis (emesis)

• Compensatory respiratory alkalosis

Pulmonary Artery CathetersSuneel Kumar MD

History

• In 1929, German surgical trainee Werner Forssman experimented on human cadavers

• Found that it was easy to guide a urologic catheter from arm veins into the right atrium

History

• Forssmann went as far as to dissect the veins of his own forearm and guided a urologic catheter into his right atrium

• Used fluoroscopic control and a mirror

• Was able to walk to get a chest x-ray

• For his trouble, he was fired

• Eventually was awarded the Nobel Prize in 1956

History

• Jeremy Swan and William Ganz from Cedars-Sinai developed a balloon-guided catheter placement

• Published in NEJM in August 1970• Idea came to Swan while watching sail

boats moving quickly on a calm day• Neither the physicians nor the

manufacturer were able to patent the balloon catheter

Functional Cardiac Anatomy

Uses of PA and Arterial Catheters• Allows assessment of both RV and LV

during diastolic and systolic phases

• Allows use of PCWP which is used to reflect the degree of pulmonary congestion

• Allows in assessment of blood flow (CO) and tissue oxygenation (SvO2)

Use of PA Catheter

• To establish diagnosis

• To guide therapy

• To monitor response to therapy

• To assess determinants of tissue oxygenation

Indications • Diagnosis of shock• Differentiate high vs

low pressure pulmonary edema

• Diagnosis of PPH • Assessment of

response to medications for PPH

• Diagnosis of valvular heart disease, intracardiac shunts, cardiac tamponade, and PE

• Monitoring and management of complicated AMI

• Assessing hemodynamic response to therapies

• Management of MOF and/or severe burns

• Management of hemodynamic instability after cardiac surgery

• Aspiration of air emboli

Indications

Contraindications

• Tricuspid or pulmonic valve mechanical protheses

• Right heart mass (thrombus or tumor)

• Tricuspid or pulmonic valve endocarditis

Approaches to Access

Approaches to Access

Approaches to Access

Approaches to Access

Insertion Technique

Proper Position

Coiled PA Catheter

Distal Cath Tip

Lung Zones of West

Lung Zones of West

PA > Pa > Pc

Pa > PA > Pc

Pa > Pc > PA

Static Column of Blood to LA

During Diastole:

• Tricuspid and mitral valves are open

• Blood leaves the atria and fill the ventricles

• Pressure between the atria and ventricles equalize

At End-Diastole:

• Mean RA pressure equalizes with the RV end-diastolic pressure

• PA diastolic and PCWP equalize with the LV end-diastolic pressure

Mean RA = RV EDP

PA EDP and PCWP = LV EDP

CVP/RA Waveform

• Three positive waves:– a wave (usually

largest)– c wave (may not be

seen)– v wave

CVP/RA Waveform

• a wave is with atrial contraction• c wave is with closure of tricuspid valve• v wave is with blood filling atrium with tricuspid valve

is closed

CVP/RA Waveform

CVP/RA Waveform and EKG

• a wave in PR interval• c wave at end of QRS,

in RST junction• v wave after T wave

Measuring Mean CVP

• Final filling of the ventricle occurs during atrial contraction (a wave)

• Therefore, average the a wave on the CVP/RA waveform

Measuring the Mean CVP

RV Waveform

• Sharp upstroke during systole, and downstroke during diastole

RV Waveform

RV Waveform

RV to PA

• As the catheter goes past the pulmonic valve:– The systolic pressure is about the same

and now has a dicrotic notch (from closure of pulmonic valve)

– The diastolic pressure increases

RV to PA

PA Waveform

• PA systole within T wave• PA diastole at end of QRS

PCWP Waveform

• Inflation of the balloon stops forward blood flow

• Creates a static column of blood between the catheter tip and the LA

PCWP Waveform

• Has a waveform characteristic of the RA, primarily with a waves and v waves

• Mean PCWP is close to PA diastolic pressure

PCWP Waveform and EKG

• a wave near end or after QRS

• v wave well after T wave

Mean PCWP Measurement

• Final filling of the left ventricle occurs during atrial contraction

• Therefore, measure the average of the a wave

• Measure at the end of expiration

Mean PCWP Measurement

12 + 6 / 2 = 9

PCWP at End Expiration

Waveform Review

Calculating Cardiac Output

• Cardiac output done by thermodilution

• Known saline bolus (5-10 mL) at known temperature (usually < 25oC) injected via the proximal lumen

• Thermistor at end of SC catheter measures the change in temperature

• Change in temperature is inversely proportional to the CO

Calculating Cardiac Output

Calculating Cardiac Output

• Stewart-Hamilton formula:

CO = (vol of injectate) x (blood temp – injectate temp) x (computation constant) / (change in blood temp as a function of time, or AUC)

Types of Shock

CO PCWP SVR

Cardiogenic

Hypovolemic /

Septic / Distributive N/

Cardiogenic Shock

• Severely decreased cardiac output

• Extracardiac obstructive shock (e.g. cardiac tamponade) has equalization of pressures

• RAP = RV diastolic = PA diastolic = PCWP

• RA with minimal x and y descents, and elevation in mean RAP

• Loss of PA respiratory variations

Constrictive Pericarditis

• Limited early diastolic filling

• Causes a plateau in the RV pressure

• “Square root sign”

• RAP has a “M” or “W” configuration

• a and v waves accentuated with rapid x and y descents

• Due to rheumatic disease, TB, metastatic carcinoma, prior chest XRT, or open heart surgery

Constrictive Pericarditis

Hypovolemic Shock

• Due to decreased blood volume

• Usually from hemorrhage or volume depletion

Distributive / Septic Shock

• Due to peripheral vasodilation

• Other causes include anaplylaxis, neurogenic shock, Addisonian crisis, toxic shock syndrome, cirrhosis, and myxedema coma

Information from PA Catheter

• Directly:– CVP– PA pressure– PCWP– CO

– SvO2

• Calculated:– Stoke volume/

index– Cardiac index– Systemic vascular

resistance (SVR)– Pulmonary vascular

resistance (PVR)– Oxygen delivery

Formulas

• SVR = (MAP – CVP) / CO

• PVR = (MPAP – PCWP) / CO

• SV = CO / HR

• CaO2 = (1.39 x Hb x SaO2) + (0.003 x PaO2)

• DO2 = CaO2 x CO

Normal Values

• SvO2• Stoke volume• Stroke index• Cardiac output• Cardiac index• MAP• CVP• PCWP• PA pressures• SVR• PVR

60-75%

50-100 mL/beat

25-45 mL/beat/m2

4-8 L/min

2.5-4.0 L/min/m2

70-110 mmHg

2-6 mmHg

8-12 mmHg

15-30 / 0-10 mmHg

900-1400 dynes.sec/cm5

40-150 dynes.sec/cm5

Case # 1

• A 65 year old man with COPD required intubation for respiratory failure. He was placed on AC.

• Shortly after intubation, he developed hypotension and a SG catheter was placed, but a PCWP could not be obtained.

Case # 1

• RA 4, sat 76%

• RV 45/0, sat 76%

• PA 45/20, mean 28, sat 77%

• PCWP ???

• BP 90/60, mean 70

• CO 5.7

• SVR 928

• 7.44 / 34 / 110, sat 99%

• Mixed venous 7.38 / 42 / 44, sat 77%

Case # 2

• A 58 year old male is admitted to the CCU as a r/o MI.

• Developed respiratory distress.

Case # 2

• RA 6, sat 65%

• RV 55/0, sat 66%

• PA 55/30, mean 45, sat 66%

• PCWP ???, sat 91%

• BP 110/80, mean 90

• CO 5.0

• SVR 1,344

• 7.44 / 35 / 80, sat 91%

• Mixed venous 7.40 / 40 / 36, sat 66%

Case # 2

Case # 3

• A 55 year old female is admitted with chest pain and shock.

• The EKG shows acute ischemic changes in the inferior limb leads.

• What is the diagnosis, and how would you treat her?

Case # 3

• RA 14, sat 55%• RV 30/15, mean 20, sat 55%• PA 30/11, mean 20, sat 55%• PCWP • BP 90/60, mean 70• CO 2.5• SVR 1,792• 7.38 / 35 / 85, sat 90%• Mixed venous 7.34 / 41 / 32, sat 55%

Case # 4

• A 50 year old male presents with syncope and shock.

• Room air ABG is obtained.

Case # 4

• RA 15, sat 48%• RV 45/0, sat 48%• PA 45/20, mean 28, sat 49%• PCWP 7• BP 50/50, mean 60• CO 2.5• SVR 1,440• 7.32 / 32 / 59, sat 89%• Mixed venous 7.28 / 38 / 28, sat 49%

Case # 5

• A 65 year old male with a two day history of weakness, dizziness, and dyspnea on exertion.

• On physical, noted to have a resting tachycardia.

• Chest x-ray shows a mediastinal mass.

Case # 5

• RA 20, sat 71%• RV 45/19, sat 71%• PA 45/20, mean 28, sat 72%• PCWP 20, sat 96%• BP 90/70, mean 77• CO 4.0• SVR 1,140• 7.39 / 38 / 85, sat 96%• Mixed venous 7.38 / 40 / 40, sat 72%

Case # 6

• A 112 year old male presents with tachypnea, confusion, and hypotension.

Case # 6

• RA 2, sat 69%

• RV 42/0, sat 69%

• PA 45/15, mean 25, sat 70%

• PCWP 8, sat 85%

• BP 70/40, mean 50

• CO 6.5

• SVR 592

• 7.55 / 32 / 50, sat 85%

• Mixed venous 7.40 / 38 / 37, sat 70%

Case # 7

• A 45 year old alcoholic with abdominal pain and hypotension.

• Chest x-ray shows a large, globular heart and a left pleural effusion.

• The Hct 45%.

Case # 7

• RA 1, sat 49%

• RV 20/0, sat 49%

• PA 20/10, mean 13, sat 49%

• PCWP 4

• BP 80/50, mean 60

• CO 3.0

• SVR 1,576

• 7.34 / 30 / 80

• Mixed venous 7.31 / 38 / 28, sat 49%

Case # 8

• 24 hours later, the prior patient in Case #7 becomes tachypneic.

• What complication has occurred?

Case # 8

• RA 4, sat 64%• RV 45/0, sat 64%• PA 45/25, mean 32, sat 65%• PCWP 12• BP 110/70, mean 85• CO 6.1• SVR 1,064• 7.46 / 32 / 55, sat 89%• Mixed venous 7.40 / 31 / 35, sat 65%

Case # 9

• A 98 year old male with confusion and hypotension.

• What kind of shock does he have?

Case # 9

• RA 12, sat 47%• RV 40/12, sat 48%• PA 40/30, mean 33, sat 49%• PCWP 29, sat 90%• BP 80/50, mean 60• CO 2.5• SVR 1,536• 7.30 / 45 / 60, sat 90%• Mixed venous 7.26 / 50 / 28, sat 49%

Case # 10

• 35 year old female with an abnormal chest x-ray and dyspnea on exertion.

• What is the diagnosis?

Case # 10

• RA 8, sat 84%

• RV 60/0, sat 85%

• PA 45/20, mean 28, sat 86%

• PCWP 10, sat 99%

• BP 120/80, mean 95

• CO 9.4

• SVR 744

• 7.40 / 40 / 99, sat 99%

• Mixed venous 7.38 / 42 / 54, sat 86%

Case # 11

• A 38 year old female presents with chest pain and dyspnea.

Case # 11

• RA 8, sat 65%

• RV 110/10, sat 66%

• PA 90/50, mean 63, sat 67%

• PCWP 12, sat 98%

• BP 110/70, mean 83

• CO 3.2

• SVR 1,872

• 7.41 / 30 / 90, sat 98%

• Mixed venous 7.37 / 33 / 37, sat 67%

Case # 12

• 18 year old female presents with exertional syncope.

Case # 12

• RA 15, sat 78%

• RV 110/27, sat 90%

• PA 80/40, mean 60, sat 91%

• PCWP 28

• BP 120/80, mean 95, sat 99%

• CO 20

• SVR 800

• 7.40 / 40 / 99, sat 99%

• Mixed venous 7.38 / 42 / 79, sat 91%

Suggested Websites

• www.pacep.org

• http://www.edwards.com/Products/PACatheters/CatheterizationTechniques.htm