Lab Nazis

I hate lab.  I hate every thing about the lab.  I even hate the people.  I hate every thing about lab.  I dread going to lab with my ABG results.  I dread it more than anything else in this field.

Okay, so I don't hate all the people.  I love the lab techs. I love the good folks who draw blood.  They generally have good people skills; they have to.  Yet there are people in the lab, who all they do is look at machines all day.  Those people tend to be choleric and dry in personality.

Okay, so not all, but many.  Enough to make the milieu of the lab seem hot and tense.  And it's not just the lab where I work my full time job, it's every lab I've ever walked into.  The people are focused on numbers, machines and tasks and don't give a rats butt about the whole picture. To them the number tells the whole story.  If a machine shows a CO2 of 60, that value is critical.  It doesn't matter that the patient is a COPD retainer with a normal CO2 of 55.

They also develop their raw, dry, pining personalities because they are forced, by all the companies and government agencies forcing tons of new regulations every day, to worry about being shut down.  Yes, there is a reason they are the way they are, as I wrote about in this post.

There's a reason there are 300,000 not needed steps in entering blood gas results and resulting them into the computer system.  It's because people who have no clue about reality are making rules and regulations.  The lab folks, the lab Nazis as I call then, are that way for a reason.  They don't intent to become Nazis, it's just what they become.  It's like if you hang out with rats all day, you become one by default.

Okay, enough lab bashing.  Seriously, folks, I find no place more stressful and tense than hospital laboratories.  It has to be the most stressful job in the world, worrying about numbers being correct; worrying about machines working properly; worrying that you meet the 289,000 stupid, moronic, regulations.  (Yes, 19,000 of those regulations might actually be necessary).

I know I'm being unfair by saying I hate the people who work in lab, because it's probably not true.  What I hate is what they become, and how they are so obsessed with numbers that they lose track of reality.  But, in their defense, it's not always their fault.  It's the fault of the morons in Washington who can't keep their noses out of our healthcare system.

I think drawing ABGs was better in the old days when ABG machines were inside RT Caves.  Surely we grunted and groaned while maintaining and fixing them, but that stress was nothing compared to what we have to deal with in the lab. Sometimes I wonder if we should have kept our mouths shut and kept it the way it was, and continued to live in happy RT lalal land.

Okay, go ahead and rip my editorial to shreds if you choose.  This is my opinion only.  I am simply terrified of the lab, like my three-year-old daughter is scared of the Ferris Wheel.  I get the ABGbies every time I go there (yes, that was a funny).

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ABG errors and how to fix them

Most ABG machines are so sophisticated that they rarely make errors.  Most studies seem to confirm this, noting that as many as 68 percent of ABG analytical errors are handling errors that occur between the time of the draw and insertion of the syringe in the ABG machine, according to John J. Ancy in his RTmagazine.com article, "Blood Gases and Preanalytical Error Prevention." 

The following are possible preanalytical errors:

1.  Exposure to air:  

• Problem:  Whole blood continues to metabolize after the draw, and for this reason it's important to have proper handling of the sample. There is a bubble in the syringe.  
• Error:  Trapped air in the syringe causes the PO2 to move toward 150, which is the PO2 of room air.  So if the actual PO2 is less than 150,  the PO2 reading may be inaccurately high as it moves up towards 150.  If the actual PO2 is greater than 150, the PO2 reading may be inaccurately low as it moves down toward 150.   CO2 become slightly lower with a slight rise in pH.  
• Solution:  Tap bubbles from syringe and aspirate air into a filter immediately after the draw.

2.  Improper mixing of heparin:

• Problem:  If dry heparin is not mixed with the blood clots may form and readings may not be accurate
• Error:  Clotting cannot be reversed.  Clots may cause to machine to break down.  
• Solution:  A small amount of dry heparin will prevent clots.  Make sure to mix the syringe, roll it between your fingers, for about one minute, and then expelling a few drops into a gauze pad, both prior to inserting the syringe into machine.  The flea in capillary blood gases should be used to mix the sample for five seconds.  

3.  Ice storage

• Problem: Past policies recommended storing the post draw ABG in a slurry of ice, although new recommendations frown upon this.  It's difficult to get outdated hospital policies changed.  
• Error:   It reduces metabolism of the blood in the syringe, but the new plastic syringes are permeable to outside oxygen molecules.  Cooling increases hemoglobin's affinity for oxygen, and this may attract oxygen molecules from ambient air to these hemoglobin molecules.  This may artificially inflate PO2.  
• Solution:  Do not use an ice slurry.  Instead, assure that the blood is inserted into the analyser within 30 minutes of the draw.  New recommendations suggest only placing the ABG on ice if the time from draw to ABG analyzer is longer than 30 minutes.  I wrote more about this here. 

4.  Art line draw:  

• Problem:  Heparin is needed to keep blood from clotting in the art line system
• Error:  Heparin in the syringe may cause inaccurate results
• Solution:  You must waste two times the dead space in the system.  How do you know the dead space volume.  Ancy explains: "If vascular line dead space is unknown, turn the stopcock to the sampling port and withdraw flush solution until blood appears in the hub of waster syringe.  The volume in the syringe at that point will be equal to the dead space, double that volume for the waste draw."

5.  Changes:  

• Problem:  Changes in patient settings may affect ABG results:  Peep changes, oxygen changes, suctioning, ventilator settings, etc.
• Error:  ABG results may be artificially high or low
• Solution:  Most recommendations suggest waiting 20-30 minutes after changing oxygen, ventilator settings, or PEEP/CPAP.  

6.  Temperature Correction:  

• Problem:  Some experts recommend if a patient has a fever the temperature on the analyzer should be adjusted to match the patient temperature.  It's difficult to change past hospital policies, and it's difficult to get doctors to understand that methods of interpreting corrected and uncorrected temperature readings may be different.  For this reason, most medical experts recommend NOT making any corrections in temperature. In other words, there are no reference ranges for other temperatures other than room temperature.  I wrote about this here.  
• Error:  Temperature can inadvertently affect ABG results by speeding up metabolism.  
• Solution:  At present, the recommendation is not to make any temperature correction.  Ideally, there should be reference ranges for ABGs at all temperatures.  Temperatures should be corrected only at the recommendation of the physician, and any changes in temperature should be reported in the comments.  Interpretation of the results is to be done by the physician who requests them.  

Related:

ABGs interpretation made easy

The argument against ABGs

What is a blood gas?

A blood gas is a test we use to determine how much oxygen and CO2 are in the patient's blood.  It's a blood draw where you insert a needle into the patient's radial artery in the wrist area, bracheal artery in the antecubital area (the backside of the elbow) or the femoral artery in the groin (thankfully we don't use this area too often).

About 90 percent of the time we draw this blood from the wrist.  We draw arterial blood because this blood is  freshly oxygenated blood from the lungs on its way to tissues.  We want to know how much oxygen is in this blood.  If oxygen is low then we may choose to supply the patient with supplemental oxygen.  We can do this with a nasal cannula or a variety of masks.

If the CO2 is high we may need to assist the patient with his ventilations in order to help the patient blow off this CO2.  The reason CO2 gets high is because the patient is not taking good enough breaths.  He may be pooping out because his lungs are diseases.  In this case, we use his CO2 level to help us determine what we can do to help him.

Another thing an ABG does is help us determine the acidity (pH) of the blood.  If a patient is in severe respiratory distress his blood may become very acidotic.  If this happens, we may need to help the patient breath so that we can get his pH back to normal.

This blood test can also help a doctor diagnose some diseases. For example, if the CO2 is chronically elevated this can be a classic sign of chronic bronchitis or emphysema.  Too see a video of an ABG being drawn you can click here.

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Blood Gases: 4-5-6, 7,8,9 Rule

Technically speaking, so long as you have an accurate pulse oximetry reading, you shouldn't have to draw an ABG to determine how well a person is oxygenating.  This is because the oxyhemoglobin dissociation curve allows you to estimate one by knowing the other.  

For instance, all you have to do use the following formula:

• Estimated PO2 = SpO2 minus 30

This can also be drawn out as the  4-5-6-7-8-9 Rule.  It goes like this.

• 4...................7
• 5...................8
• 6...................9

or...

• 40 PO2 = 70 SpO2
• 50 PO2 = 80 SpO2
• 60 PO2 = 90 SpO2

Essentially, SpO2 can be used to estimate PO2 and level of hypoxemia. 

90% SpO2	60 PO2	Mild Hypoxemia	No oxygen needed
80% SpO2	50 PO2	Moderate Hypoxemia	Oxygen needed
70% SpO2	40 PO2	severe Hypoxemia	Oxygen needed

Further reading:

1. ABG Interpretation Made Easy: Acid Base Balance
2. ABG Interpretation Made EAsy: Oxygenation
3. Oxyhemoglobin Dissociation Curve

Cord blood gases made easy

Cord Blood Gases Made Easy 

Why draw Cord Blood Gases?

Basically, the reason we draw cord blood gases (CBG) is in case there is a lawsuit years down the road accusing the delivering doctor of causing an anoxic brain injury that resulted in disorders such as cerebral palsy. 

The cord blood can prove that neurological deficits that develop in infants were caused by an anoxic brain injury that occurred after delivery or before delivery and was not the result of an anoxic episode at birth. The cord blood gas has been shown to be proof positive in about 80% of the cases (According to PubMed.com), and has in many cases cleared physicians from litigation.

When should a Cord Blood Gas be drawn?

A cord blood gas does not need to be drawn unless a baby is born and has a low APGAR score within 5 minutes of delivery, such as a 3 or less. When the APGAR score is low a cord blood gas should automatically be drawn.

What is a Cord Blood Gas?

When we refer to cord blood we are referring to blood drawn from the placenta after delivery. If you look at a placental cord (see picture below) you will see one large vein surrounded by two arteries that wrap around the vein.

According to PubMed.com, the Umbilical Vein delivers freshly oxygenated blood from the mom to the baby. Since an anoxic brain injury in the baby in not likely to change the pH of the Umbilical Vein, this is not where you will want to draw a cord gas from.

The Umbilical Artery is where the baby's venous circulation dumps unoxygenated blood. This is blood that was on its way back to the mom's heart and lungs to pick up oxygen. Thus, when you draw a cord gas for litigation purposes you will want to draw from one of the two Umbilical Arteries.

Blood from the Umbilical Artery is called a Cord Arterial Blood Gas (CABG), and basically shows how the baby was doing prior to birth.

From this blood we want to watch for acidosis. Since anaerobic metabolism occurs during the absence of oxygen, the acid base balance (pH) of the baby's body increases due to an increase in the amount of lactic acid produced. Therefore pH is the most important indicator in the CABG.

What are acceptable CABG values?

If the pH of the CABG is above 7.10, then we know that the baby was not hypoxic during the delivery, and if there was a hypoxic episode it occurred prior to the delivery process.  You know this because the pH had time to normalize.

The anoxic episode may have occurred weeks or months prior to birth, or it may have occurred hours before birth. Either way, this proves the episode did not occur as a result of the delivery and should clear the physician of litigation.

What are critical CABG values?

If the pH is less than 7.10 the episode was more likely acute and the episode may have occurred during the delivery. You know this because the pH did not have time to normalize.

According to obgyn.org, some experts believe a pH of 7.0 with a significant metabolic component is a more significant sign of asphyxia at birth, and may lead to significant neurological dysfunction during life, or possibly even death.

Also according to obgyn.org, "Even when this low pH threshold is used to define significant acidemia, most newborns in this category will be neurologically normal, with no apparent morbidity."

What baby’s are at greatest risk for anoxic brain injuries?

The baby's at greatest risk of anoxic brain injury are premature infants, according to obgyn.org. They are at higher risk of "intracranial hemorrhage and subsequent neurological dysfunction, such as cerebral palsy.

Without umbilical cord blood gas analysis, these neurological complications could be incorrectly attributed to intrapartum or birth asphyxia, especially if the latter is solely based on APGAR scores.

Normal umbilical cord blood values in the premature infant virtually eliminate the diagnosis of significant intrapartum hypoxia or birth asphyxia."

Can you just draw an arterial cord blood gas?

Most experts recommend drawing both arterial and venous gas for the purpose of comparison.  One physician suggested “that the cost of approximately $2 per delivery should be absorbed by the hospital as a risk-management measure.

How do draw Cord Blood Gases?

Immediately following the delivery of the infant and before placental separation, obtain cord blood gases as follows (refer to pictures below):

·        A 6 inch segment of the cord should be isolated between 2 clamps (See figure 2 Below)

·        Select two 1cc heparinized blood gas syringes

·        Label the two syringes with the patient name and date of birth

·        Write on one syringe umbilical vein and the other umbilical artery

·        Identify the umbilical vein and umbilical artery

·        Grasp one end of the umbilical cord to prevent it from moving

·        With your other hand hold the syringe marked umbilical artery as you would hold a pencil

·        Prepare to insert the syringe parallel to the artery to avoid passing through the narrow vessel (this is demonstrated in figure 3 below).

·        Insert syringe into umbilical artery at a 45 degree angle (Be careful not to go all the way through the artery)

·        Pull back slowly on the syringe to allow it to fill with blood

·        Ideally we would like at least 1cc, however we need at least 0.3cc of blood

·        Remove the needle from the umbilical artery

·        Carefully discard the needle

·        Remove any air bubbles from the syringe

·        Follow the same above steps for drawing blood from the umbilical vein

·        Call respiratory therapy to run the samples as soon as possible

What do you do with a cord gas once it is drawn?

Once a CABG and a CAVG has been drawn, hospital policy requires that they be placed on ice, and respiratory therapy should be paged as soon as possible.  The samples should ideally be run through the ABG machine within 30 minutes of the draw

What are normal CABG values?                  What are normal CAVG results?

·     pH:        7.27 (range 7.22–7.32)           ph:        7.34  (range 7.28–7.40

·     pCO2:    50 (range 42–58)                   PCO2:  40.7  (range 32.8–38.6)

·     pO2       18 (range 12–24)                   pO2:     30  (range 28-32)

·     HCO3:   22 (range 24-26)                    HCO3:  21.4  (range 19-24)

·     BE:       -2.7  (range –5.5– 0.1)            BE:      -2.4  (range –4.4-0.4) 

The following are conditions that would warrant a CABG:

·     Any abnormality during delivery process (prolonged pushing, difficult delivery)

·     Low 5 minutes APGAR score (less than 3)

·     Any abnormality in patient condition that occurs within 1st 5 minutes after birth

·     Premature birth

·     Post term birth

·     Meconium in amniotic fluid

·     Intubation

·     Positive pressure ventilation (Neo-puff or bag mask ventilation)

·     Suctioning

·     Cesarean-section

·     Severe growth retardation

·     Abnormal fetal heart rate tracing

·     Maternal thyroid disease

·     Intrapartum fever

·     multifetal gestation

Conclusion:  Essentially, a CABG with a pH of 7.1 or greater can prove the infant was well oxygenated at time of birth, and can clear the delivering physician from litigation.  

Umbilical cord blood gases: routine measurement may exonerate ob.gyns

(From OB/GYN News) Dr. Hankins said that following the birth of a baby with Cerebral Palsy (CP), there are many factors that are beyond obstetricians' control in the cascade of events that spiral toward litigation--but doing cord blood studies is not one of them.

"This is something that is within our hands, but once it escapes you, it is gone. The only opportunity the obstetrician has to obtain this information is going to be right at the moment of birth," said Dr. Hankins, professor of ob.gyn.at the University of Texas, Galveston.

He recommended that immediately following delivery a segment of the umbilical cord be doubly clamped and placed aside to remain stable for 30 minutes for pH and blood gas assessment.

"[Neither] ACOG nor anyone else has suggested that every baby that's delivered should have cord blood studies, but I say it would be a tremendously positive thing to do and it should get rid of some of this frivolous litigation."

He recommended drawing both arterial and venous gas for the purpose of comparison, and he suggested that the cost of approximately $2 per delivery should be absorbed by the hospital as a risk-management measure.

"It's not subjective; it's pure objective data. If you have a pair of blood gases--arterial and venous--by that alone, and with no other data, I can tell you much of what was happening in that delivery room," he said.

The task force document set the following criteria for the precise definition of an acute intrapartum event sufficient to cause cerebral palsy:

·         Evidence of metabolic acidosis in fetal umbilical cord arterial blood obtained at delivery (pH less than 7 and a base deficit of 12 mmol/L).

·         Early onset of severe or moderate neonatal encephalopathy in infants born at 34 or more weeks' gestation.

·         Cerebral palsy of the spastic quadriplegic or dyskinetic type.

·         Exclusion of other identifiable etiologies, such as trauma, coagulation disorders, infectious conditions, or genetic disorders.

By Kate Johnson, OB/GYN News Contributing Writer, July 1, 2004
http://findarticles.com/p/articles/mi_m0CYD/is_13_39/ai_n6114078/
COPYRIGHT 2004 International Medical News Group

COPYRIGHT 2008 Gale, Cengage Learning

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The argument against ABGs

The argument for venous blood gases instead of arterial blood gases

Something we've been discussing at Shoreline Medical recently is the possibility of doing fewer
arterial blood gases (ABG) and more venous blood gases.

Sure an ABG is necessary when monitoring a patient in respiratory distress, although for the most part, there really isn't any more information you can obtain in an ABG that you can't simply obtain from a venous blood gas, coupled with end tital CO2 monitoring (ETCO2) and oxygen saturation (SpO2) monitoring.

Consider you have a patient with diabetes. The doctor wants to determine pH. If a pH is all the doctor wants, then a venous blood gas will work just great, as venous and arterial pHs are basically the same.

A 1998 study (as noted in this article from Emergency Medicine) found that in patients with diabetic keto acidosis, the venous pH was remarkably similar to the arterial pH.

Our Sepsis protocol calls for any patient suspected of having Sepsis to have an ABG. The reason is to get a baseline pH. Since this is the only reason, a venous blood gas would suffice.

The same with overdose patients. Poison control wants an ABG to be drawn when certain medicines are overdosed on. The reason is to check for pH. This is another example when a venous poke would suffice.

Think about it though. A venous poke is much less invasive and risky as an arterial poke, and the lab is in the room of the patient anyway drawing all the other labs. So, then it would be much better on the patient just to have all labs, including ABG, on just one poke.

In fact, according to Emergency Medicine, "When Is Venous Blood Gas Analysis Enough?" (38(12):44-48, 2006), revealed that a study performed in 1996 determined that most patients said a venous poke was about half as painful as an arterial poke.

You have a patient on a ventilator. Currently our protocol calls for daily ABGs. Our medical director is presently trying to convince the medical staff where I work that serial ABGs are not needed. What is needed is a continuous pulse oximeter and an end tidal CO2 monitor.

Then, 30 minutes to an hour after intubation, an ABG should be drawn just to get your baseline pH and to make sure the ETCO2 monitor and SpO2 correlate with the actual PO2 and CO2. That's it. From then forth all you need is daily venous pH. To monitor PO2, all you have to do is monitor the SpO2 and ETCO2.

A normal SpO2 is 90 or better. According to the oxyhemoglobin association curve, the PO2 is 30 less than the SPO2, therefore an SPO2 of 90% is equivelent to an SpO2 of 60, and an SpO2 of 80 correlates to a PO2 of 50. So there you have it.

Thus, according to the oxyhemoglobin disassociation curve, the formula goes like this (SPO2 minus 30 = PO2):

SPO2 of 90 = a PO2 of 60
SPO2 of 80 = a PO2 of 50
SPO2 of 70 = a PO2 of 40

It's basically called the 4-5-6-7-8-9 rule.

As far as monitoring CO2, all you have to do is monitor ETCO2. As the ETCO2 rises and falls, so to does the PCO2. A normal ETCO2 would be 30 to 50. Unless the patient is a CO2 retainer, all ETCO2 results greater or less than that should be reported to the physician.

Basically, if you have a patient who is not in respiratory distress, an ABG is never needed.

The proof

The toughest argument I've had is convincing doctors that a venous pH is basically the same as arterial pH. I remember once being called to do a stat ABG on a patient, and the pH on the patient was 6.78 and the CO2 was 75. The doctor was convinced I got venous blood and wanted me to redraw.

I took the gas to a second doctor, and he too was convinced I had obtained venous blood. I knew I had arterial not just by how forcefully the blood entered the syringe, but because the bicarb was 33 which shows the patient was probably a CO2 retainer to start with. Yet the doctors made me redraw the ABG. Of course it came out exactly the same, and they once again were convinced I had venous blood.

So the debate is ongoing. Yet, as you can tell by the picture, venous and arterial pH are essentially the same in a healthy patient. Why doctors are so convinced there is a major difference between the two is beyond me. Likewise, the bicarb (HCO3) is essentially the same too.

The only major difference is PO2, which can be monitored by saturations, which is completely non-invasive. There is no reason to ever draw an ABG just to prove that the PO2 is low. Again, all you have to do is subtract 30 from the SpO2 and you have your PO2.

The Emergency Medicine article notes a study done way back in 1985 that basically proved that "a venous pH of 7.25 or higher predicted an arterial pH of 7.2 or higher in 98% of all cases, which makes VBG testing valuable as a screening procedure.If the results are normal, ABG analysis should not be necessary. Conversely, abnormal venous levels predicted abnormal arterial values, but again in a nonlinear fashion. A venous pH of 7 or lower, for example, predicted an arterial pH of 7.2 or lower in 98% of cases. "

Here's another catcher the Emergency Medicine article notes. I have tried to convince doctors for years that an ABG is not needed during a code because if a patient is not breathing you already know the pH is low. Likewise, regardless of what the ABG shows, it's not going to alter what you do to try to save the life of the patient. So there is no need to rush to do an ABG.

In other words, you do not need to do an ABG to diagnose hypoxemic respiratory failure when the patient is showing obvious signs of hypoxemic respiratory failure.  Attempts to draw blood only delay treatment, and this can only increase morbidity and mortality.

The article is the first I've found that attempts to prove my point. It notes the following:

In cardiac arrest victims, the disparity between arterial and venous values is even greater. During cardiac arrest, tissue hypoxia is all but a certainty and is reflected by the lower pH and higher PCO₂ on the venous side. A 1986 study by Weil demonstrated a significantly lower pH in venous samples (mean, 7.15 vs 7.41 in arterial samples) and a significantly elevated PCO₂ (mean, 74 mm Hg vs 32 mm Hg) in these patients. In clinical practice, however, knowledge of either the arterial or venous pH or PCO₂ during cardiac arrest does not alter management, making the debate less relevant.

What's most interesting is my point was proven way back in 1986. Why is this information not translated in medical school? Yet, regardless, the argument is simple, that ABGs are needed sometimes to help a physician manage the care of a patient, yet more often than not a VBG will suffice.

How to keep your lab from failing inspections

ABG machines are a great device to have around, particularly in emergency situations. Yet recently the lab bosses have created new recommendations and policies for us to follow that are very inconvenient. However, as I have learned, a necessary evil.

An article in the May 10, 2010, issue of the AARC Times by John Campbell, "Preventing 'proficiency Referral' from happening to your health care organization," does a great job of detailing the importance of proper ABG and ABG machine handling in order to pass laboratory inspections to prevent mandatory lab closure.

We all have shortcuts, some of which we choose not to share for obvious reasons. One shortcut of many RTs in my department is we do so few ABGs that we rarely placed a sticker with the patient's name on them. We also rarely heeded the yellow warning lights on the ABG machine that warned that the equipment must be checked before further ABGs can be reported by the machine.

However, a recent crackdown has changed our behavior. The new policy is as follows:

• Identify patient
• proper sanitisers
• label syringe
• Check for yellow light on ABG machine
• If yellow, fix problem or run maintenance
• If question mark on ABG report throw it away.
• Run monthly control (every RT must do this once a year)

Some of those rules are common sense, although some are a pain in the arse, particularly the check the yellow light and do maintenance. You see, we used to have the ABG machine in the RT Cave, and the reason we gave it to lab was so we wouldn't have to do this anymore.
So here we are learning how to do it once again. In a way, it seems we might as well take care of it ourselves. Yet the RT Boss has decided it's best off in lab where they can do the appropriate check on it, after all, he noted, "They are the lab equipment experts."
Actually, I know of many RT departments that run their own ABG machine, and they do so just fine. So, technically speaking, there is no reason we can't do it ourselves. But, be it as it may, it's no longer our machine.
Inspections of labs are made at least once a year by MANY companies, including the Centers of Medicare and Medical Services (CMS), or some other CMS contracted agency commonly called CLIA inspection or by some other accredited agency that is deemed qualified to do these things such as the College of American Pathologies or the Joint Commission.
Once an inspection is done the hospital must not lapse, because new inspectors could arrive at anytime.
The reason for inspections are obvious: machines are expected to be accurate. Results are important for obvious reasons, and inspections -- however annoying or redundant -- are needed.
Here are some of the things inspectors look for:

• Only qualified and selected individuals handle and draw samples and run machine, etc.
• One person in charge of device responsible for making sure things are done in accordance to policies.
• ABGs are labeled properly. The inspectors are known to look in waste dispensers to make sure syringes are labeled.
• Proper documentation
• Critical values are noted and highlighted on ABG results
• A note on ABG stating that doctor or nurse was notified of critical values
• All staff rotate doing controls
• Problems immediately reported to lab director or medical director

Refusal or failure of procedure or evaluation will or MAY result in closing of the lab, which would mean we RTs would be unable to use the ABG machine. ABGs would have to be run to other hospitals and run through their ABG machine.
According to Campbell, "CMS gives 5 days notice to offending labs that its CLIA certificate is being revoked. This notice will hold that the proficiency referral was intentional even if, in fact, it was not. This notice can come by mail or even face, and the 5 day period also includes weekends."
Campbell notes there is an appeals process, yet CMS usually wins. Likewise, lab closings are reported to local newspapers, which can provide a bad image to the hospital. He notes monetary costs can be staggering, from $500,000 to a million in legal fees, decreased credibility and image, decrease confidence in your facility, and inability to run labs at your hospital.
So, however annoying, follow the ABG policy set at your hospital.

Cord blood gases: Here's all you need to know

Every respiratory therapist dreads having to draw cord blood gases, and all OB nurses dread the circumstances that require them to be drawn. So, that said, what are the indications for drawing cord blood gases, what is the significance of drawing them, and why do we draw them in the first place?

Basically, the reason we draw cord blood gases is in case their is a lawsuit that might take place years down the road accusing the delivering doctor of causing an anoxic brain injury that resulted in diseases such as cerebral palsy.

The cord blood can prove that neurological deficits that develop in infants were caused by an anoxic brain injury that occurred after delivery or before delivery and was not the result of an anoxic episode at birth. The cord blood gas has been shown to be proof positive in about 80% of the cases (According to PubMed.com), and has in many cases cleared physicians from litigation.

A cord blood gas does not need to be drawn unless a baby is born has a low APGAR score within 5 minutes of delivery, such as a 3 or less. When the APGAR score is low a cord blood gas should automatically be drawn.

When we refer to cord blood we are referring to blood drawn from the placenta after delivery. If you look at a placental cord (see picture) you will see one large vein surrounded by two arteries that wrap around the vein.

According to PubMed.com, the Umbilical Vein delivers freshly oxygenated blood from the mom to the baby. Since an anoxic brain injury in baby in not likely to change the pH of the Umbilical Vein, this is not where you will want to draw a cord gas from.

The Umbilical Artery is where the baby's venous circulation dumps unoxygenated blood. This is blood that was on its way back to the mom's heart and lungs to pick up oxygen. Thus, when you draw a cord gas for litigation purposes you will want to draw from one of the two Umbilical Arteries.

Blood from the Umbilical Artery is called a Cord Arterial Blood Gas (CABG), and basically shows how the baby was doing prior to birth.

From this blood we want to watch for acidosis. Since anaerobic metabolism occurs during the absence of oxygen, the acid base balance (pH) of the baby's body increases due to increase in the amount of lactic acid produced. Therefore pH is the most important indicator in the CABG.

If the pH of the CABGis above 7.10, then we know that the baby was not hypoxic during the delivery, and if there was a hypoxic episode it occurred prior to the delivery process. It may have occurred weeks or months prior to birth, or it may have occured hours before birth. Either way, this proves the episode did not occur as a result of the delivery and should clear the physician of litigation.

If the pH is less than 7.10 the episode was more likely acute and the episode may have occurred during the delivery. If the pH is greater than 7.10, the episode typically occurred before the delivery.

According to obgyn.org, Some experts believe a pH of 7.0 with a significant metabolic component is a more significant sign of asphyxia at birth, and may lead to significant neurological dysfunction during life, or possibly even death.

Also according to obgy.org, "Even when this low pH threshold is used to define significant acidemia, most newborns in this category will be neurologically normal, with no apparent morbidity."

The baby's at greatest risk of anoxic brain injury are premature infants, according to obgyn.org. They are at higher risk of "intracranial hemorrhage and subsequent neurological dysfunction, such as cerebral palsy. Without umbilical cord blood gas analysis, these neurological complications could be incorrectly attributed to intrapartum or birth asphyxia, especially if the latter is solely based on APGAR scores. Normal umbilical cord blood values in the premature infant virtually eliminate the diagnosis of significant intrapartum hypoxia or birth asphyxia."

So, ideally, you will want the pH to be normal. If it is normal and there is an anoxic brain injury the doctor can prove by the CABG results that since the pH had time to return to normal the injury occurred prior to delivery and the injury did not occur as a result of delivery. If the pH less than 7.1 chances are the injury occurred during delivery.

Once a CABG has been drawn it can be set aside. Most studies now show that a CABG does not need to be placed on ice, and is good for up to an hour.

• pH: 7.28 (+/-.5)
• pCO2: 49 (+/-8)
• pO2: 18 (+/- 6.2)
• HCO3: 2.5-3.5
• BE: 10

Critical values that might show anoxic brain injury during birth (acidosis):

• pH less than 7.0
• CO2 greater than 50
• PO2 variable (remember this is the baby's venous blood, so the PO2 is relatively low)
• BE is normal or low (10 or less)

Critical values that might show injury due to metabolic cause:

• pH less low (less than 7.25, critical is 7.10 as mentioned above)
• PO2 less than 20
• CO2 is normal or high
• BE greater than 10 (Best indicator of metabolic cause

The following are conditions that would warrant a CABG:

• Any abnormality during delivery process
• Low 5 minutes APGAR score (less than 3)
• Any abnormality in patient condition that occurs within 1st 5 minutes after birth
• Premature birth
• Post term birth
• Meconium in amniotic fluid
• Intubation
• Positive pressure ventilation (Neo-puff or bag mask ventilation)
• Suctioning
• Cesarean-section
• Severe growth retardation
• abnormal fetal heart rate tracing
• maternal thyroid disease
• intrapartum fever
• multifetal gestation

The following are sources used for this post:

• OBGYN.org: Cord Blood Gases to Determine Umbilical Artery Acid Base Balance
• Umbilical Cord Blood Gas Analysis
• Cord blood analysis
• FamilyPracticeNotebook.com
• Tips for how to draw CABGs
• Umbilical cord blood gases: routine measurement may exonerate ob.gyns

Are capillary blood gases coming back?

When I started working as an RRT I was instructed on the correct method of doing a capillary blood gas (cbg) on a neonate. When I was told I had to cut the foot with a blade and drip blood into a tube I cringed, "I don't' want to do that."

For a couple years thereafter I gulped every time my pager went off that I had to go to OB for a bad baby. Just the thought that I might have to do one of those CBG things made my cringe.

After I had been here five years it occur ed to me the pediatricians who work here had never ordered a CBG. Yippy! I never had to do one of those dreaded things. Then one day I noticed that the CBG kids were gone too. It was clear I would never have to do one.

A few days ago, however, I was talking with a pediatrician from Spectrum Health in Grand Rapids, Michigan, and he said to me, "Do you guys to capillary blood gases where you work?"

"No!" I said, "and thankfully so."

"Do you even have kits anymore?"

"No. The pediatricians must have realized those things are pretty much useless."

"Well," he said, "the reason I asked is because we do CBGs now at Butts. Too many studies show that umbilical lines cause to many infections, so we try to stay away from them wherever possible."

Oh, I thought. So you're not on my side. "Oh! So you're recommending that we do ABGs?"

"Yes. I know most hospitals got rid of them, but now we've pretty much decided that a venous pH, along with a sat monitor, can give you a pretty decent estimate of what is going on with the baby."

Actually that does make sense to me. I've debated with doctors in our ER for years that a venous pH is not much different from an arterial. And we all try to convince doctors that a sat is all that is needed to confirm hypoxia.

"Do you guys have the capacity to do them," he asked, "I mean on your ABG machine?"

"Yes. I think we do."

He said, "The procedure is much better than it used to be. All we do now is prick them they same way you prick someone when you are going to check their sugar. It's not as bad as it used to be."

"Well that shouldn't be so bad then," I said. "And since we send all our bad babies to you guys, all our protocols are based on your protocols anyway. So, if you recommend we do CBGs, I bet we'll probably do CBGs"

"Good deal," he said.

So, will CBG kits find their way back to hospitals? Do you guys do CBGs where you work? Does anyone have any research on the value of CBGS, or studies that show UV lines cause too many infections to make CBGs worthwhile?