Mark Klimek Lecture Notes LECTURE 1: Acid Base Balance & Ventilator Interpreting blood gases
(remember the rules of the B’s)
If the pH and the bicarb are both in the same direction then it’s metaBolic (Bicarb Both Bolic), if they are in different directions then it is respiratory If bicarb is normal and the pH is low or high then its respiratory
You will be given 8 values for arterial blood gas, always first look at the pH and the bicarb first You get acidosis and alkalosis from the pH
LABS: ABG’s
The normal pH is 7.35-7.45 The normal bicarb is 22-26 (the bicarb years where you make all the decisions
[22-26 years old], or 2+2+2=6)
The normal CO2 is 35-45 (same as pH)
Signs and Symptoms with ABG’s
As the pH goes up so does my patient oIf the pH goes up, every system in your body gets more irritable/hyperexcitable As the pH goes down so does my patient oIf the pH goes down, systems in your body shut down
Except for potassium- When pH goes down, potassium goes up If the pH goes up (alkalosis): you will find irritability, hyperreflexia (3&4), tachypnea, tachycardia, borborygmi (increased bowel sounds), seizure (need suctioning at the bed side because they can seize and aspirate)
If pH goes down (acidosis): hyporeflexia, bradycardia, lethargy, obtunded, paralytic ileus, coma, respiratory arrest (need bag-mask ventilation bag at bedside for respiratory arrest), +1 reflexes MACkussmal- compensatory and respiratory pattern for only acid base disorder: MAC- Metabolic ACidosis Respiratory Acidosis multiple choice example: What would you see with a patient who is in respiratory acidosis?
a.+1 reflex, b.diarrhea, c.adynamic ileus (no movement) , d.spasm, e.urinary retention , f.paraxysmol atrial tachycardia, g.second degree lovitz, type 2 heart block (impulse is being slowed) ,
h.hypokalemia
LAB: REFLEXES
0&1-hyporeflexia 2-normal
3&4- hyperreflexia EXAMPLE: (In general what do pain meds do? ANSWER: They sedate you, they are CNS depressants: lethargy, lucidity, reflexes at +1, hyporeflexia, obtundent
Causes of Acid Base Imbalance
Don’t get signs and symptoms mixed up with causation!!!
What causes something is the opposite of what the signs and symptoms are
oEXAMPLE: diarrhea will cause a metabolic acidosis but once you get acidotic, it will shut your bowels down and you will get a paralytic ileus. The first question you should ask yourself if the scenario involves a lung problem.
oIs it a respiratory problem? BUT remember it can still be respiratory acidosis/alkalosis…
Next question you ask yourself…
ois the client overventilating or underventilating?
oIf the patient is overventilating pick alkalosis
oIf they are underventilating pick acidosis If the client is overventilating.. it has an attachment to the word- alkalosis (because they are both OVER)… ventilating OVER becomes respiratory ALKALOSIS If the client is undeventilating.. it has an attachment to the word- acidosis (because they are both UNDER)- ventilating UNDER becomes respiratory ACIDOSIS
Examples:
1)A woman is overzealously using her breathing techniques during labor, what acid base disorder will she exhibit? Overventilation oRespiratory Alkalosis
2)A child is near drowning, what acid base disorder would it be? Underventilating oRespiratory Acidosis 3)Your patient has emphysema, what acid base disorder would it be? Underventilating oRespiratory Acidosis Ventilating does not mean respiratory rate.. respiratory rate is irrelevant- ventilation has to do with gas exchange!!
Examples: 1)Patient has pneumonia in 4 lobes of the lung, breathing at 50/min and their SO2 is at 78 on 8 liters per max
oExplanation: Breathing really fast while still having a low O2 level means that the patient is still underventilating because respiratory rate has nothing to do with it. Everyone pays so much attention to rate when they should be paying closer attention to the SO2. oIf your SO2 is good and you are breathing slow, you are fine but if your SO2 is low and you’re breathing fast, you are actually underventilating. A lot of times the respiratory rate compensates- pay attention to SO2!!!
2)Patient is on a PCA pump, what acid base imbalance would tell you they need to come off that thing?
oA PCA pump depresses respirations. So, patients need to come off of it as soon as possible because if they were getting too much it would make their respiratory rate go really down which would make the patient underventilate so the answer would be respiratory acidosis.
oSo respiratory acidosis would tell you that you need to come off the PCA pump. What if its not lung?
It would be Metabolic. Only one scenario that you will answer metabolic alkalosis : if the patient has prolonged gastric vomiting or suctioning
pick metabolic alkalosis.. Why?
oPt is losing acid... pt will become basic Otherwise everything else that is not lung or the above, pick metabolic acidosis
Ex. 1)Patient had GI surgery and has had an NG tube to low intermittent gone post suctioning for 3 days, what acid base disorder would he most likely exhibit?
oMetabolic alkalosis 2)Patient has hyper emesis gravidarum , what acid base disorder are they going
to exhibit
oMetabolic alkalosis
3)Continuation: Pt is going to be dehydrated- what acid base disorder would they have?
oMetabolic acidosis
4)Pt has acute renal failure, what acid base disorder would this be?
oMetabolic acidosis- its not lung or vomiting or suctioning so it has to be metabolic acidosis 5)A pt with infantile diarrhea would have what acid base disorder?
oMetabolic acidosis 6)A pt with third degree burns over 60 percent of the body?
(remember the rules of the B’s)
If the pH and the bicarb are both in the same direction then it’s metaBolic (Bicarb Both Bolic), if they are in different directions then it is respiratory If bicarb is normal and the pH is low or high then its respiratory
You will be given 8 values for arterial blood gas, always first look at the pH and the bicarb first You get acidosis and alkalosis from the pH
LABS: ABG’s
The normal pH is 7.35-7.45 The normal bicarb is 22-26 (the bicarb years where you make all the decisions
[22-26 years old], or 2+2+2=6)
The normal CO2 is 35-45 (same as pH)
Signs and Symptoms with ABG’s
As the pH goes up so does my patient oIf the pH goes up, every system in your body gets more irritable/hyperexcitable As the pH goes down so does my patient oIf the pH goes down, systems in your body shut down
Except for potassium- When pH goes down, potassium goes up If the pH goes up (alkalosis): you will find irritability, hyperreflexia (3&4), tachypnea, tachycardia, borborygmi (increased bowel sounds), seizure (need suctioning at the bed side because they can seize and aspirate)
If pH goes down (acidosis): hyporeflexia, bradycardia, lethargy, obtunded, paralytic ileus, coma, respiratory arrest (need bag-mask ventilation bag at bedside for respiratory arrest), +1 reflexes MACkussmal- compensatory and respiratory pattern for only acid base disorder: MAC- Metabolic ACidosis Respiratory Acidosis multiple choice example: What would you see with a patient who is in respiratory acidosis?
a.+1 reflex, b.diarrhea, c.adynamic ileus (no movement) , d.spasm, e.urinary retention , f.paraxysmol atrial tachycardia, g.second degree lovitz, type 2 heart block (impulse is being slowed) ,
h.hypokalemia
LAB: REFLEXES
0&1-hyporeflexia 2-normal
3&4- hyperreflexia EXAMPLE: (In general what do pain meds do? ANSWER: They sedate you, they are CNS depressants: lethargy, lucidity, reflexes at +1, hyporeflexia, obtundent
Causes of Acid Base Imbalance
Don’t get signs and symptoms mixed up with causation!!!
What causes something is the opposite of what the signs and symptoms are
oEXAMPLE: diarrhea will cause a metabolic acidosis but once you get acidotic, it will shut your bowels down and you will get a paralytic ileus. The first question you should ask yourself if the scenario involves a lung problem.
oIs it a respiratory problem? BUT remember it can still be respiratory acidosis/alkalosis…
Next question you ask yourself…
ois the client overventilating or underventilating?
oIf the patient is overventilating pick alkalosis
oIf they are underventilating pick acidosis If the client is overventilating.. it has an attachment to the word- alkalosis (because they are both OVER)… ventilating OVER becomes respiratory ALKALOSIS If the client is undeventilating.. it has an attachment to the word- acidosis (because they are both UNDER)- ventilating UNDER becomes respiratory ACIDOSIS
Examples:
1)A woman is overzealously using her breathing techniques during labor, what acid base disorder will she exhibit? Overventilation oRespiratory Alkalosis
2)A child is near drowning, what acid base disorder would it be? Underventilating oRespiratory Acidosis 3)Your patient has emphysema, what acid base disorder would it be? Underventilating oRespiratory Acidosis Ventilating does not mean respiratory rate.. respiratory rate is irrelevant- ventilation has to do with gas exchange!!
Examples: 1)Patient has pneumonia in 4 lobes of the lung, breathing at 50/min and their SO2 is at 78 on 8 liters per max
oExplanation: Breathing really fast while still having a low O2 level means that the patient is still underventilating because respiratory rate has nothing to do with it. Everyone pays so much attention to rate when they should be paying closer attention to the SO2. oIf your SO2 is good and you are breathing slow, you are fine but if your SO2 is low and you’re breathing fast, you are actually underventilating. A lot of times the respiratory rate compensates- pay attention to SO2!!!
2)Patient is on a PCA pump, what acid base imbalance would tell you they need to come off that thing?
oA PCA pump depresses respirations. So, patients need to come off of it as soon as possible because if they were getting too much it would make their respiratory rate go really down which would make the patient underventilate so the answer would be respiratory acidosis.
oSo respiratory acidosis would tell you that you need to come off the PCA pump. What if its not lung?
It would be Metabolic. Only one scenario that you will answer metabolic alkalosis : if the patient has prolonged gastric vomiting or suctioning
pick metabolic alkalosis.. Why?
oPt is losing acid... pt will become basic Otherwise everything else that is not lung or the above, pick metabolic acidosis
Ex. 1)Patient had GI surgery and has had an NG tube to low intermittent gone post suctioning for 3 days, what acid base disorder would he most likely exhibit?
oMetabolic alkalosis 2)Patient has hyper emesis gravidarum , what acid base disorder are they going
to exhibit
oMetabolic alkalosis
3)Continuation: Pt is going to be dehydrated- what acid base disorder would they have?
oMetabolic acidosis
4)Pt has acute renal failure, what acid base disorder would this be?
oMetabolic acidosis- its not lung or vomiting or suctioning so it has to be metabolic acidosis 5)A pt with infantile diarrhea would have what acid base disorder?
oMetabolic acidosis 6)A pt with third degree burns over 60 percent of the body?
