Basic Blood Gas Interpretation
description
Transcript of Basic Blood Gas Interpretation
![Page 1: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/1.jpg)
Basic Blood Gas Interpretation
205b
![Page 2: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/2.jpg)
Values Measured
• PaO2 – amount of oxygen in the arterial blood
• SaO2 – percent saturation of the hemoglobin as
measured by a CO-oximeter
![Page 3: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/3.jpg)
Values Measured
• SpO2 – percent saturation of the hemoglobin as
measured by a pulse oximeter
• Hb – amount of hemoglobin present
![Page 4: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/4.jpg)
Values Measured
• Hct (Hematocrit) – percent of the blood that is
composed of cells
• pH – concentration of hydrogen ions (H+) in the
arterial blood
![Page 5: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/5.jpg)
Values Measured
• PaCO2 – amount of carbon dioxide in the arterial
blood
• HCO3ˉ – amount of bicarbonate in the arterial blood
![Page 6: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/6.jpg)
Values Measured
• B.E. (base excess/base deficit) – the total of all
buffering systems in the arterial blood
• CO – amount of carbon monoxide present in the
arterial blood
![Page 7: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/7.jpg)
Determination of Oxygenation
• Normal Values– PaO2
• 80 – 100 mmHg
– Mild hypoxemia • 60 – 79 mmHg
– Moderate hypoxemia • 40 – 59 mmHg
– Severe hypoxemia • < 40 mmHg
– SaO2 • 93% – 97%
• 88-92% COPD/lung disease
– Hb • Males: 13.5 – 16.5 g/dl• Females: 12 – 15 g/dl
– Hct • Males: 42 – 54%• Females: 38 – 47%
![Page 8: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/8.jpg)
Determination of Oxygenation
• Normal Values– CaO2
• Males: 17.1 – 21.7 ml/dl• Females: 14.9 – 19.7 ml/dl
– COHb • <3%
![Page 9: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/9.jpg)
Method of Determining Oxygenation
• Evaluate the PaO2
– 80 – 100 mmHg: normal oxygenation
– > 100 mmHg: hyperoxygenation
– 60 – 79 mmHg: mild hypoxemia
![Page 10: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/10.jpg)
Method of Determining Oxygenation
• Evaluate the PaO2
– 40 – 59 mmHg: moderate hypoxemia
– < 40 mmHg: severe hypoxemia
![Page 11: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/11.jpg)
Method of Determining Oxygenation
• Evaluate the SaO2
– > 93%: normal oxygenation
– < 93%: may be hypoxemic; examine the hemoglobin
![Page 12: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/12.jpg)
Method of Determining Oxygenation
• Evaluate the Hb
– 12 – 16 g/dl: normal
– < 12 g/dl: anemic
– > 16 g/dl: polycythemic
![Page 13: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/13.jpg)
Method of Determining Oxygenation
• Evaluate the CaO2
– 17 – 20 ml/dl: normal
– 15 – 17 ml/dl: mild hypoxia
– 12 – 14.9 ml/dl: moderate hypoxia
– < 12 ml/dl: severe hypoxia
![Page 14: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/14.jpg)
Method of Determining Oxygenation
• Other factors in oxygenation
– Abnormal forms of hemoglobin:
• Detectable by CO-oximeter, not pulse oximeter
![Page 15: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/15.jpg)
Estimate PaO2
• Predicated PaO2 based on age= Estimated value of what there PaO2 might be
• • PaO2= 110 – half the person’s age• example: 20 year old. 110 – 10= PaO2 100• • (PaO2 of 60 will equal approximately 90% saturation based
on the oxyhemoglobin curve)
![Page 16: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/16.jpg)
Determination of Acid Base Balance
• pH is equal to the –log of the hydrogen ion
– pH = – Log [H+]
![Page 17: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/17.jpg)
Determination of Acid Base Balance
• Henderson-Hasselbalch equation
– pH = pK + Log HCO3 H2CO3
– pH = pK + Log HCO3 (Renal) Paco2 x0.03 (Lungs)
![Page 18: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/18.jpg)
Determination of Acid Base Balance
• pH measures the blood’s acidity or alkalinity
– Must always be determined first when assessing
acid- base balance
![Page 19: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/19.jpg)
Determination of Acid Base Balance
• PaCO2 is our stimulus to breathe
– A high PaCO2 indicates that not enough carbon dioxide is
being exhaled
– A low PaCO2 indicates that too much carbon dioxide is
being eliminated
![Page 20: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/20.jpg)
Determination of Acid Base Balance
• Evaluate base excess or bicarbonate (metabolic
parameter)
– Is it acidic or alkaline
– 22- 26 mEq/L is normal
– > 26 Indicates metabolic alkalosis
– < 22 Indicates metabolic acidosis
![Page 21: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/21.jpg)
Determination of Acid Base Balance
• Bicarbonate is the base or buffer that “neutralizes”
hydrogen ions (HCO3)
• Bicarbonate is made in the red blood cells, liver,
and kidney
![Page 22: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/22.jpg)
Determination of Acid Base Balance
• When bicarbonate levels are elevated, an excess
of alkalinity exists in the metabolic systems
• When bicarbonate levels are low, an excess of
acidity exists in the metabolic systems
![Page 23: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/23.jpg)
Determination of Acid Base Balance
• If the pH is not normal, identify whether it is acidic
or alkaline
![Page 24: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/24.jpg)
Determination of Acid Base Balance
• Identify whether the PaCO2 or bicarbonate
disturbance (acidosis or alkalosis) matches The pH
change (acidosis or alkalosis)
– This is the “cause” of the problem and represents where
treatment should be directed. (e.g. if pH is acidic, PaCO2
is alkaline and bicarbonate is acidic, the problem is a
metabolic acidosis)
![Page 25: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/25.jpg)
Determination of Acid Base Balance
• If the pH is not 7.40 but within the normal range
(7.35 - 7.45), the disturbance is fully compensated
• If both the respiratory and metabolic parameters
match the pH, the problem is a combined
disturbance
![Page 26: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/26.jpg)
Determination of Acid Base Balance
• A change in the opposite direction (acidosis or
alkalosis) by the parameter (PaCO2 or bicarbonate)
that does not match the pH is an attempt to restore
the pH (referred to as partial compensation)
![Page 27: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/27.jpg)
Evaluation of Compensation
pH Normal
PaCO2 NormalHCO3 Normal
Normal Acid-Base Balance
PaCO2 ElevatedHCO3 Elevated
Fully Compensated Respiratory Acidemia or
Fully Compensated Metabolic Alkalemia
PaCO2 DecreasedHCO3 Decreased
Fully Compensated
Respiratory Alkalemia of Fully
Compensated Metabolic Acidemia
![Page 28: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/28.jpg)
Arterial Punctures
• Indications1
– Need to evaluate ventilation, acid-base balance, and
oxygenation of blood
– Assess the patient’s response to therapy
– Monitor and assess the severity and progression of a
disease process1 Excerpt from the AARC Clinical Practice Guideline for Sampling for Arterial Blood Gas Analysis
![Page 29: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/29.jpg)
Arterial Punctures
• Contraindications1
– Negative Allen test
– Presence of a surgical shunt proximal to the sample site
http://www.youtube.com/watch?v=HRcVVGBb9fg
1 Excerpt from the AARC Clinical Practice Guideline for Sampling for Arterial Blood Gas Analysis
![Page 30: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/30.jpg)
Dialysis shunt
![Page 31: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/31.jpg)
Arterial Punctures
• Contraindications1
– Presence of a lesion at the sample site
– Coagulopathy or medium to high dose anticoagulation
therapy (relative contraindication)
1 Excerpt from the AARC Clinical Practice Guideline for Sampling for Arterial Blood Gas Analysis
![Page 32: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/32.jpg)
Hematoma
![Page 33: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/33.jpg)
Arterial Punctures
• Hazards and complications1
– Arteriospasm
– Air or clotted blood emboli
– Hematoma
1 Excerpt from the AARC Clinical Practice Guideline for Sampling for Arterial Blood Gas Analysis
![Page 34: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/34.jpg)
Arterial Punctures
• Hazards and complications1
– Hemorrhage
– Pain
– Arterial occlusion
1 Excerpt from the AARC Clinical Practice Guideline for Sampling for Arterial Blood Gas Analysis
![Page 35: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/35.jpg)
Arterial Punctures
• Hazards and complications1
– Trauma to the vessel
– Vasovagal response
– Patient or sample contamination
– Anaphylaxis (if local anesthetic used, Xylocain)
1 Excerpt from the AARC Clinical Practice Guideline for Sampling for Arterial Blood Gas Analysis
![Page 36: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/36.jpg)
Arterial Punctures
• Assessment of need for arterial sample1
– Initiation, change, or discontinuation of therapy (oxygen
or ventilatory support)
– History and physical indicators
1 Excerpt from the AARC Clinical Practice Guideline for Sampling for Arterial Blood Gas Analysis
![Page 37: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/37.jpg)
Arterial Punctures
• Assessment of need for arterial sample1
– Presence of other abnormal diagnostic tests or findings
– Baseline study for pulmonary rehabilitation program
1 Excerpt from the AARC Clinical Practice Guideline for Sampling for Arterial Blood Gas Analysis
![Page 38: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/38.jpg)
Arterial Punctures
• Frequency of monitoring1
– Dependent upon clinical status of the patient and
presence of indications
– If frequent monitoring required, use alternating sites or
indwelling arterial catheter
1 Excerpt from the AARC Clinical Practice Guideline for Sampling for Arterial Blood Gas Analysis
![Page 39: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/39.jpg)
Arterial Punctures
• Allen Test
– Performed to determine presence of adequate collateral
circulation in the hand
– Cannot be used with uncooperative or unconscious
patients
![Page 40: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/40.jpg)
Arterial Punctures
• Allen Test
– Procedure
• Have patient clench hand into a tight fist
• Apply pressure to occlude flow through the radial and ulnar
arteries
• Open hand; observe to ensure that the palm and fingers are
blanched
![Page 41: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/41.jpg)
Arterial Punctures
• Allen Test
– Procedure
• Remove pressure from the ulnar artery
• Observe time necessary for flushing of hand
• Test is negative for collateral circulation if flushing does not
occur within 20 seconds; an alternative site is chosen
![Page 42: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/42.jpg)
The Modified Allen Test
The modified Allen test. A, The hand is clenched into a tight fist and pressure is applied to the radial and ulnar arteries. B, The hand is opened (but not fully extended); the palm and fingers are blanched. C, Removal of pressure on the ulnar artery should result in flushing of the entire hand.
![Page 43: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/43.jpg)
Which Artery to Choose?
• The radial artery is superficial, has collaterals and is easily compressed. It should almost always be the first choice.
• Other arteries (femoral, dorsalis pedis, brachial) can be used in emergencies.
![Page 44: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/44.jpg)
![Page 45: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/45.jpg)
![Page 46: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/46.jpg)
Preparing to perform the Procedure:
• Make sure you and the patient are comfortable.• Assess the patency of the radial and ulnar arteries.
![Page 47: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/47.jpg)
Procedure For Obtaining an Arterial Sample (Radius)
• Confirm the order in the patient’s chart
• Note any contraindications and notify physician if
any exist
![Page 48: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/48.jpg)
Procedure For Obtaining an
Arterial Sample (Radius)
• Ensure that patient is in a steady state (no changes
in oxygen status for at least twenty minutes)
• Obtain and assemble necessary equipment
![Page 49: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/49.jpg)
Procedure For Obtaining an
Arterial Sample (Radius)
• Wash hands, don protective equipment, explain
the procedure to the patient
• Position the patient correctly
![Page 50: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/50.jpg)
Procedure For Obtaining an
Arterial Sample (Radius)
• Perform an Allen test and confirm collateral
circulation
• Cleanse the site with 70% isopropyl alcohol or
other antiseptic
![Page 51: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/51.jpg)
Procedure For Obtaining an
Arterial Sample (Radius)
• Inject local anesthetic, if hospital protocol
• Heparinize the syringe, if not already heparinized
![Page 52: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/52.jpg)
Procedure For Obtaining an
Arterial Sample (Radius)
• Palpate and secure the artery
• Insert the needle, bevel up, at a 45° angle through
the skin until blood pulsates into the syringe
![Page 53: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/53.jpg)
![Page 54: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/54.jpg)
Procedure For Obtaining an
Arterial Sample (Radius)
• Withdraw the needle when sufficient sample is
obtained
• Apply firm pressure to the puncture site using a
gauze pad
![Page 55: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/55.jpg)
Procedure For Obtaining an
Arterial Sample (Radius)
• Maintain pressure for a minimum of five minutes,
longer if patient is on anticoagulant therapy
• Expel any air bubbles from the syringe
![Page 56: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/56.jpg)
Procedure For Obtaining an
Arterial Sample (Radius)
• Mix the sample and label it
• Place the sample in an icy slush (only if a delay in
running the sample is expected)
![Page 57: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/57.jpg)
Procedure For Obtaining an
Arterial Sample (Radius)
• Dispose of any waste material in the appropriate
container
• Document the procedure
![Page 58: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/58.jpg)
Arterial Puncture
http://www.youtube.com/watch?v=KbszTXeg71g
![Page 59: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/59.jpg)
The Kit
![Page 60: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/60.jpg)
Air bubbles
• Gas equilibration between ambient air (pO2 ~ 150, pCO2~0) and arterial blood.
• pO2 will begin to rise, pCO2 will fall• Effect is a function of duration of exposure and
surface area of air bubble.• Effect is amplified by pneumatic tube transport.
![Page 61: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/61.jpg)
Transport
• After specimen collected and air bubble removed, gently mix and invert syringe.
• Because the wbcs are metabolically active, they will consume oxygen.
• Plastic syringes are gas permeable.• Key: Minimize time from sample acquisition to analysis.
![Page 62: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/62.jpg)
Transport
• Placing the AGB on ice may help minimize changes, depending on the type of syringe, pO2 and white blood cell count.
• Its probably not as important if the specimen is delivered immediately.
![Page 63: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/63.jpg)
Pre-Analysis Errors
• Presence of air in the sample
– Recognized by presence of bubbles or froth,
inconsistent PaCO2
– Allows diffusion of CO2 into the air, lowering the PaCO2
– As the CO2 diffuses, pH is raised
![Page 64: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/64.jpg)
Pre-Analysis Errors
• Presence of air in the sample
– In low PaO2 states, O2 diffuses into the blood, raising the
PaO2
– In high PaO2 states, O2 diffuses out of the blood,
lowering the PaO2
![Page 65: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/65.jpg)
Pre-Analysis Errors
• Venous admixture
– Recognized by failure of syringe to fill by pulsations,
inconsistent PaO2
– Higher PaCO2 than expected
![Page 66: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/66.jpg)
Pre-Analysis Errors
• Venous admixture
– Lower pH than expected
– Lower PaO2 than expected (may be significantly lower)
![Page 67: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/67.jpg)
Pre-Analysis Errors
• Metabolic effects
– Caused by excessive time lag between sampling and
analysis or improper storage of sample
– Increase in PaCO2 as cellular metabolism continues
– Decrease in pH secondary to increase in PaCO2
– Decrease in PaO2 as cells use up oxygen
![Page 68: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/68.jpg)
Pre-Analysis Errors
• Excessive anticoagulant in syringe
– Caused by allowing excessive heparin to remain in
syringe (dead space only should have heparin)
– Lowers PaCO2
– Raises pH
![Page 69: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/69.jpg)
Pre-Analysis Errors
• Excessive anticoagulant in syringe
– Raises low PaO2
– Lowers high PaO2
![Page 70: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/70.jpg)
Capillary Sampling
• Used as an alternative to arterial sampling in
infants and small children.
• Sample may approximate pH and PaCO2 values;
PaO2 value is generally inaccurate
![Page 71: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/71.jpg)
Capillary Sampling
• Indications2
– ABG analysis is indicated, but access is not possible
– Assessment of initiation, administration, or change in
therapy is indicated
– Change in patient status is detected
2 Excerpt from the AARC Clinical Practice Guideline for Capillary Blood Gas Sampling for Neonatal and Pediatric Patients
![Page 72: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/72.jpg)
Capillary Sampling
• Indications2
– Monitoring severity or progression of disease is
desirable
– Noninvasive monitor readings are abnormal
2 Excerpt from the AARC Clinical Practice Guideline for Capillary Blood Gas Sampling for Neonatal and Pediatric Patients
![Page 73: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/73.jpg)
Capillary Sampling
• Contraindications2
– Capillary punctures should not be performed at or
through:
• The posterior curvature of the heel (Bone Damage)
• Fingers of neonates (nerve damage)
2 Excerpt from the AARC Clinical Practice Guideline for Capillary Blood Gas Sampling for Neonatal and Pediatric Patients
![Page 74: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/74.jpg)
Capillary Sampling
• Contraindications2
– Capillary punctures should not be performed at or
through:
• Heel of an infant who has begun walking
• Previous puncture sites
2 Excerpt from the AARC Clinical Practice Guideline for Capillary Blood Gas Sampling for Neonatal and Pediatric Patients
![Page 75: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/75.jpg)
Capillary Sampling
• Contraindications2
– Capillary punctures should not be performed at or
through:
• Inflamed, swollen, or edematous tissue
• Localized areas of infection
• Cyanotic or poorly perfused areas2 Excerpt from the AARC Clinical Practice Guideline for Capillary Blood Gas Sampling for Neonatal and
Pediatric Patients
![Page 76: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/76.jpg)
Capillary Sampling
• Contraindications2
– Contraindicated:
• In patients less than twenty-four hours of age
• When there is a need for direct analysis of oxygenation
• When there is a need for direct analysis of arterial blood
2 Excerpt from the AARC Clinical Practice Guideline for Capillary Blood Gas Sampling for Neonatal and Pediatric Patients
![Page 77: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/77.jpg)
Capillary Sampling
• Contraindications2
– Relatively contraindicated:
• When peripheral vasoconstriction is present
• In the hypotensive patient
• In polycythemia
2 Excerpt from the AARC Clinical Practice Guideline for Capillary Blood Gas Sampling for Neonatal and Pediatric Patients
![Page 78: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/78.jpg)
Capillary Sampling
• Precautions and/or complications2
– Contamination and infection of the patient
– Inappropriate management through use of capillary
rather than arterial samples
2 Excerpt from the AARC Clinical Practice Guideline for Capillary Blood Gas Sampling for Neonatal and Pediatric Patients
![Page 79: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/79.jpg)
Capillary Sampling
• Precautions and/or complications2
– Burns
– Bone calcification
– Bruising
2 Excerpt from the AARC Clinical Practice Guideline for Capillary Blood Gas Sampling for Neonatal and Pediatric Patients
![Page 80: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/80.jpg)
Capillary Sampling
• Precautions and/or complications2
– Pain
– Hematoma
– Nerve damage
2 Excerpt from the AARC Clinical Practice Guideline for Capillary Blood Gas Sampling for Neonatal and Pediatric Patients
![Page 81: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/81.jpg)
Capillary Sampling
• Precautions and/or complications2
– Scarring
– Bleeding
– Tibial artery laceration
2 Excerpt from the AARC Clinical Practice Guideline for Capillary Blood Gas Sampling for Neonatal and Pediatric Patients
![Page 82: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/82.jpg)
Capillary Sampling
• Assessment of need2
– Should be performed only when a documented need
exists and arterial access is unavailable or
contraindicated
2 Excerpt from the AARC Clinical Practice Guideline for Capillary Blood Gas Sampling for Neonatal and Pediatric Patients
![Page 83: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/83.jpg)
Capillary Sampling
• Assessment of need2
– When initiation, administration, or change in therapy
occurs
– When noninvasive monitoring and assessment indicates
a change in condition has occurred
2 Excerpt from the AARC Clinical Practice Guideline for Capillary Blood Gas Sampling for Neonatal and Pediatric Patients
![Page 84: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/84.jpg)
Procedure for Obtaining a Capillary Sample
• Verify the order and the need for a capillary sample
• Note any complications and notify the physician if
any exist
![Page 85: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/85.jpg)
Procedure for Obtaining a Capillary Sample
• Ensure that patient is in a steady state (no changes
in oxygen status for at least twenty minutes)
• Wash hands and don protective equipment
![Page 86: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/86.jpg)
Procedure for Obtaining a Capillary Sample
• Select the site
• Warm the site up to 42° C For ten minutes using a
compress, heat lamp or commercial hot pack
![Page 87: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/87.jpg)
Procedure for Obtaining a Capillary Sample
• Cleanse the skin with an antiseptic solution
• Puncture the skin (less than 2.5 mm) with a lancet
![Page 88: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/88.jpg)
Procedure for Obtaining a Capillary Sample
• Wipe away the first drop of blood and observe free
flow (do not squeeze)
• Fill the sample tube from the middle of the drop
until it is full
![Page 89: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/89.jpg)
Procedure for Obtaining a Capillary Sample
• Place the flea in the tube and seal the ends
• Tape sterile cotton or a bandage over the puncture
site
![Page 90: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/90.jpg)
Procedure for Obtaining a Capillary Sample
• Mix the sample by moving the magnet back and
forth along the tube
• Place the sample in an icy slush
![Page 91: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/91.jpg)
Procedure for Obtaining a Capillary Sample
• Dispose of waste materials properly
• Document the procedure
![Page 92: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/92.jpg)
Capillary Tubes
![Page 93: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/93.jpg)
Neonatal Puncture Site
![Page 94: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/94.jpg)
Capillary Sampling
Finger Stick Heel Stick
![Page 95: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/95.jpg)
Capillary Blood Gas
![Page 96: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/96.jpg)
• http://www.youtube.com/watch?v=7DPhP22KRbc&feature=related
• http://www.youtube.com/watch?v=N5Id1kOQzv4
Capillary Blood Gas
![Page 97: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/97.jpg)
• http://www.youtube.com/watch?v=pTjhMylgje0&feature=related
Cord Gas
![Page 98: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/98.jpg)
Arterial Lines
![Page 99: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/99.jpg)
• The arterial line with transducers is usually used to obtain accurate blood pressure readings every few seconds. This is especially important in monitoring the hemodynamic status of a critical patient. With an arterial line, the immediate effects of medication can be seen. Both systolic, diastolic and mean pressures can be monitored immediately. This is especially important when pressors such as Nipride, dopamine or Levophed are being used.
• Another advantage of using an arterial line is that frequent blood samples can be obtained.
Indications
![Page 100: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/100.jpg)
![Page 101: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/101.jpg)
![Page 102: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/102.jpg)
This system consists of• arterial line connected by saline filled non-compressible
tubing to apressure transducer. This converts the pressure waveform into an electrical signal which is displayed on the bedside monitor
• pressurized saline for flushing
A-line monitoring
![Page 103: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/103.jpg)
![Page 104: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/104.jpg)
• Sources of error• failure of any one of the components in system• transducer position
– pressure displayed is pressure relative to position of transducer– in order to reflect blood pressure accurately transducer should be at level of heart.
Over-reading will occur if transducer too low and under-reading if transducer too high– transducer must be zeroed to atmospheric pressure
• damping. Important to have appropriate amount of damping in the system. Inadequate damping will result in excessive resonance in the system and an overestimate of systolic pressure and an underestimate of diastolic pressure. The opposite occurs with overdamping. In both cases the mean arterial pressure is the most accurate. An underdamped trace is often characterized by a high initial spike in the waveform.
A-Line Monitoring
![Page 105: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/105.jpg)
A-line Monitoring
![Page 106: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/106.jpg)
• distal ischemia• arterial thrombosis• embolism. • infection• hemorrhage
– disconnection– around line
• accidental drug injection• damage to artery eg aneurysm
A-line Complications
![Page 107: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/107.jpg)
• http://www.wonderhowto.com/how-to-draw-blood-from-arterial-line-343135/
Drawing Blood from an A-line
![Page 108: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/108.jpg)
• 1. Prepare a 500 ml bag of normal saline. Most institutions no longer use a heparinized bag. Spike the bag with the transducer administration set. Remove all air from the tubing and transducer set. Pay particular attention to the transducer part of the Tubing and the flush port. The smallest air bubble must be removed to insure transducer accuracy. The easiest way to do this is to pressurize the bag up to 300 mm Hg, then invert the bag, and fast flush it to remove all air from the bag.
• 2. Pressurize the pressure bag to 300 mm Hg. The purpose of this is to provide backpressure to prevent blood from contaminating the transducer.
• 3. With the transducer connected to the monitor, select arterial monitor, and perform a transducer check by fast flushing the line. As you do this, you should see a change in the waveform. This is called a square wave test.
• http://www.youtube.com/watch?v=F1s08XoKdYY
A-line Placement
![Page 109: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/109.jpg)
A-line Placement
• 4. Zero the transducer and monitor by placing the transducer at the phlebostatic axis of the patient. Close the line off to patient and open to air. Press zero on the monitor. To monitor pressure, close the port off to an air and open to patient.
• 5. At this point the patient catheter is ready to be connected. Connect the catheter and fast flush to clear the catheter of blood.
• 6. You should now see an arterial waveform on the monitor with arterial blood pressure and mean should be on the monitor screen. Check for good waveform
![Page 110: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/110.jpg)
MORE ABG PRACTICE
![Page 111: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/111.jpg)
Can You Interpret this Blood Gas?
Blood Gas Drawn on Room Air
• pH 7.39
• PaCO2 42 mmHg
• HCO3 23 mEq/L
• PaO2 97 mmHg
![Page 112: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/112.jpg)
Can You Interpret this Blood Gas?
Blood Gas Drawn on Room Air
• pH 7.39
• PaCO2 42
mmHg
• HCO3 23 mEq/L
• PaO2 97 mmHg
• Normal acid-base balance with normal oxygenation
![Page 113: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/113.jpg)
Can You Interpret this Blood Gas?
Blood Gas Drawn on Room Air
• pH 7.32
• PaCO2 49
mmHg
• HCO3 26 mEq/L
• PaO2 60mmHg
![Page 114: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/114.jpg)
Can You Interpret this Blood Gas?
Blood Gas Drawn on Room Air
• pH 7.32
• PaCO2 49
mmHg
• HCO3 26 mEq/L
• PaO2 60mmHg
• Uncompensated or acute respiratory acidemia with mild hypoxemia
![Page 115: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/115.jpg)
Can You Interpret this Blood Gas?
Blood Gas Drawn on Room Air
• pH 7.31
• PaCO2 60
mmHg
• HCO3 29 mEq/L
• PaO2 58 mmHg
![Page 116: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/116.jpg)
Can You Interpret this Blood Gas?
Blood Gas Drawn on Room Air
• pH 7.31
• PaCO2 60
mmHg
• HCO3 29 mEq/L
• PaO2 58 mmHg
• Partially compensated respiratory acidemia with moderate hypoxemia
![Page 117: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/117.jpg)
Can You Interpret this Blood Gas?
Blood Gas Drawn on Room Air
• pH 7.50
• PaCO2 60
mmHg
• HCO3 19 mEq/L
• PaO2 60 mmHg
![Page 118: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/118.jpg)
Can You Interpret this Blood Gas?
Blood Gas Drawn on Room Air
• pH 7.50
• PaCO2 60
mmHg
• HCO3 19 mEq/L
• PaO2 60 mmHg
• Lab error
![Page 119: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/119.jpg)
Can You Interpret this Blood Gas?
Blood Gas Drawn on Room Air
• pH 7.35
• PaCO2 63
mmHg
• HCO3 33 mEq/L
• PaO2 60 mmHg
![Page 120: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/120.jpg)
Can You Interpret this Blood Gas?
Blood Gas Drawn on Room Air
• pH 7.35
• PaCO2 63
mmHg
• HCO3 33 mEq/L
• PaO2 60 mmHg
• Compensated respiratory acidemia with mild hypoxemia
![Page 121: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/121.jpg)
Can You Interpret this Blood Gas?
Blood Gas Drawn on Room Air
• pH 7.28
• PaCO2 28
mmHg
• HCO3 8 mEq/L
• PaO2 104 mmHg
![Page 122: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/122.jpg)
Can You Interpret this Blood Gas?
Blood Gas Drawn on Room Air
• pH 7.28
• PaCO2 28
mmHg
• HCO3 8 mEq/L
• PaO2 104 mmHg
• Partially compensated metabolic acidemia with hyperoxygenation
![Page 123: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/123.jpg)
Can You Interpret this Blood Gas?
Blood Gas Drawn on Room Air
• pH 7.36
• PaCO2 24
mmHg
• HCO3 18 mEq/L
• PaO2 109 mmHg
![Page 124: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/124.jpg)
Can You Interpret this Blood Gas?
Blood Gas Drawn on Room Air
• pH 7.36
• PaCO2 24
mmHg
• HCO3 18 mEq/L
• PaO2 109 mmHg
• Fully compensated metabolic acidemia with hyperoxygenation
![Page 125: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/125.jpg)
Can You Interpret this Blood Gas?
Blood Gas Drawn on Room Air
• pH 7.45
• PaCO2 48
mmHg
• HCO3 33 mEq/L
• PaO2 79 mmHg
![Page 126: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/126.jpg)
Can You Interpret this Blood Gas?
Blood Gas Drawn on Room Air
• pH 7.45
• PaCO2 48
mmHg
• HCO3 33 mEq/L
• PaO2 79 mmHg
• Fully compensated metabolic alkalemia with mild hypoxemia
![Page 127: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/127.jpg)
Can You Interpret this Blood Gas?
Blood Gas Drawn on Room Air
• pH 7.30
• PaCO2 30
mmHg
• HCO3 35 mEq/L
• PaO2 81 mmHg
![Page 128: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/128.jpg)
Can You Interpret this Blood Gas?
Blood Gas Drawn on Room Air
• pH 7.30
• PaCO2 30
mmHg
• HCO3 35 mEq/L
• PaO2 81 mmHg
• Lab error
![Page 129: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/129.jpg)
Can You Interpret this Blood Gas?
Blood Gas Drawn on Room Air
• pH 7.49
• PaCO2 47
mmHg
• HCO3 35 mEq/L
• PaO2 81 mmHg
![Page 130: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/130.jpg)
Can You Interpret this Blood Gas?
Blood Gas Drawn on Room Air
• pH 7.49
• PaCO2 47
mmHg
• HCO3 35 mEq/L
• PaO2 81 mmHg
• Partially compensated metabolic alkalemia with normal oxygenation
![Page 131: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/131.jpg)
Can You Interpret this Blood Gas?
Blood Gas Drawn on Room Air
• pH 7.24
• PaCO2 77
mmHg
• HCO3 7 mEq/L
• PaO2 28 mmHg
![Page 132: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/132.jpg)
Can You Interpret this Blood Gas?
Blood Gas Drawn on Room Air
• pH 7.24
• PaCO2 77
mmHg
• HCO3 7 mEq/L
• PaO2 28 mmHg
• Combined acidemia with severe hypoxemia
![Page 133: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/133.jpg)
Can You Interpret this Blood Gas?
Blood Gas Drawn on Room Air
• pH 7.36
• PaCO2 45
mmHg
• HCO3 25 mEq/L
• PaO2 108 mmHg
![Page 134: Basic Blood Gas Interpretation](https://reader035.fdocuments.us/reader035/viewer/2022062310/5681670a550346895ddb74ba/html5/thumbnails/134.jpg)
Can You Interpret this Blood Gas?
Blood Gas Drawn on Room Air
• pH 7.36
• PaCO2 45
mmHg
• HCO3 25 mEq/L
• PaO2 108 mmHg
• Lab error
– ( PaCO2 and PaO2 cannot
total more than 140 on
room air)