Lecture 3: Abnormal Physiology Flashcards
HR values that would be concerning for CVP pt
<50 or >120 at rest
uncontrolled/new arrhythmia
BP values that would be concerning for CVP pt
> 180/90
<90/60
MAP <60
SPO2 values that would be concerning for CVP pt
<90% at rest
acute change in O2 demand/device
what could cause bradycardia in a pt
heart block
adverse drug reaction
metabolic dysfunction
post sx
meds
myocarditis
lab abnormalities
abnormal breathing patterns
what could cause tachycardia in a pt
meds
anemia
hypotension
infection
anxiety/fear
ETOH use
pain
substance abuse
overall mechanism of abnormal HR
ischemia to SA node
decrease in myocardial contractility
Things to watch out for with HR changes that are NOT normal
HR drops with increase work
severely exaggerated rise in HR with increased work
minimal rise with increased work
irregular rhythm that is not present at rest
worsening rhythm that is present at rest
CONTEXT IS IMPORTANT
What is chronotropic incompetence
small % of pts with CAD
to have this pt cannot be on any meds that limit HR (chronotropic meds)
max symptom = limiting HR with exertion that is well below age predicted max
defense mechanism to maintain coronary aa blood flow in presence of CAD
signifies advanced CAD with poor prognosis, high morbidity and mortality
what could cause a pt to be hypotensive
meds
acute blood loss
diastolic dysfunction
bradycardia
shock
position change
dehydration
arrhythmias
what could cause a pt to be hypertensive
lifestyle
high BMI
smoking
comorbidities
pain
anxiety
substance abuse
2 overall mechanisms for abnormal BP
ischemic/damaged ventricle will rapidly reach max stroke volume (lower than it should be for correlated increase in work)
OR
abnormal/rapid rise in HR and stroke volume = higher cardiac output (higher than expected for work load); altered CO will alter SVR which leads to abnormal BP response
different abnormal responses for SBP
rising response >20-30 mmHg
flat response = SBP doesn’t rise linearly with work (context important)
falling response = SBP drop with increased work (context important); associated S&S make response more concerning
if pt is not on any anti HTN meds and has a SBP drop + SBP <140 during max exercise = higher rate of sudden cardiac death
falling response with SBP can be associated with…
pronounced ST segment depression
angina
cardiomyopathy
large MI
low EF
abnormal diastolic response to exercise
> 10 mmHg rise or drop with increased work
any massive shift in DBP is concerning; will likely accompany abnormal SBP changes
abnormal MAP response to exercise
<60 is concerning for end organ perfusion
context is important
what could cause a pt to have hypoxemia
blood loss
hypoventilation
heart or lung disease
infection/sepsis
anemia
PE
sleep apnea
what response to exercise may indicate autonomic dysfunction
exaggerated HR/BP responses that do not correspond to workload
ineffective redistribution of blood flow to working mm could be caused by
sympathetic nervous system dysfunction
inability to adequately vasodilator/constrict
what is an arrhythmia
disturbance ein cardiac rhythm
abnormality in site of origin impulse, rate, regularity, or conduction
tachyarrhythmia = HR >100bpm
bradyarrhythmia = HR <60
causes of arrhythmias
other areas of heart contain ectopic foci (cells with automaticity) that are suppressed by dominant SA node
meds
infection
electrolytes
age
comorbidities
substance abuse
what is atrial flutter
regular atrial quivering
atrial contracting out of sync with ventricles
high amplitude P wave
what is atrial fibrillation
lower amplitude, irregular atrial quivering
elimination of atrial kick
absent P wave (no P wave = no PR interval)
what is a univocal Pre-Ventricular Contraction (PVC)
premature ventricular depolarization
ectopic foci in ventricles fires with an impulse generated in Purkinje fibers instead of SA node
2 simultaneous PVCs = couplet
how many simultaneous PVCs = VTACH
6 times
what is a multifocal PVC
PVCs that originate in different ectopic foci with different electrical configurations
suggestive of more severe electrical conductivity problems
higher cardiac irritability
what is a bigeminy
PVC every other normal beat
more concerning than trigeminy; 50% ventricular contraction is abnormal
what is a trigeminy
PVC every 3rd normal beat
what is an AFib with rapid ventricular response (RVR)
abnormal ventricular response to irregular atrial contractions (Afib alone the ventricles still work normal and HR is normal)
HR >120 bpm
what is supra ventricular tachycardia (SVT)
HR > 150 being set by SA node and not slowed by AV node
absent T wave
not getting full ventricular filling with fast HR = not getting full ejection
what is ventricular tachycardia (VTach)
wide QRS complex tachycardia
absent P waves
what is tornadoes de pointes
specific type of VTach with rotation around an axis of electrical activity
caused by hypo magnesia
rogue clusters of cells that rotate back and forth for control of electrical activity
what is ventricular fibrillation (VFib)
ventricles quiver inconsistently, no true contraction
very disorganized electrical activity
rapid loss of CO
only arrhythmia that an AED is successful with
what is asystole
no heart beat
what is atrioventricular heart block
abnormality in electrical conduction between atria and ventricles
PR interval = time between atrial and ventricular contractions
first degree AV heart block
impulse conducted from atria to ventricles is delayed
consistent PR intervals >0.20 seconds
very common cause of resting bradycardia
what is type I 2nd degree heart block = Mobitz I = Wenckebach
PR interval gets progressively longer then QRS drops
atrial impulse gets predictably blocked
what is type II 2nd degree heart block = Mobitz II
PR interval is consistent then QRS drops
atrial impulse to ventricle gets unpredictably dropped
still have a skipped beat but not as predictable
what is 3rd degree heart block = complete/total HB
all atrial indexes are blocked at AV node and none get transmitted to ventricles
SA and AV node are conducting electrical impulses in complete disconnection from one another
P intervals are consistent with each other, R intervals are consistent with each other, but these are not in coordination with one another
absolute contraindication to activity
what is Troponin and its importance as well as normal/abnormal values
most important biomarker correlated to cardiac ischemia
cTnT <0.1 = normal
cTnI <0.3 = normal
Troponin T is more sensitive than Troponin I
drawn serially until peaked
no exertion until down trending and stable
what is BNP (B type Natriuretic Peptide) and normal values
important biomarker correlated to myocardial tissue damage from overstretch
BNP <100 = normal
BNP > 400 indicative of heart failure
fluid overloaded, dyspnea, severe exercise intolerance
no direct contraindication, all symptom limited
normal Hemoglobin values
M = 14-18
F = 12-16
most transfusion parameters is Hgb <7
strong correlation with symptoms needed to make clinical decisions
normal hematocrit values
M = 42-52%
F = 37-47%
abnormalities indicate other problems/pathologies
symptom limited
WBC normal values/indications
5000-10000
indicative of multi-system infection/pathology
symptom limited
platelet normal values and meaning
150-400
low values = pt at higher risk for bleeding
high values = pt at higher risk for clot formation
<50 = no resistance exercise
<20 = consult with provider
what is pancytopenia
decrease in RBC, WBC, and platelets
what is thrombocytopenia
decrease in platelets
what is throbscytosis
increase in platelets
what is neutropenia
decrease in all WBCs
what is anemia
decrease in RBCs
what is polycythemia
increase in RBCs
normal sodium levels and function in CP system
135-145
“sodium swells” to maintain BP, volume, and pH
normal potassium levels and function in CP system
3.5-5.0
“P pumps” heart and mm
normal magnesium levels and function in CP system
1.3-2.1
M mellows the mm
normal calcium levels and function in CP system
9-10.5
Keeps the “3 Bs” strong (bones, blood, beats)
what is normal prothrombin time (PT) and what do high values indicate
11-12.5 sec
higher = increased bleeding/bruising
> 20 = high risk for bleeding into tissues
what is normal partial thromboplastin time and what do high values indicate
21-35 sec
higher = increased bleeding/bruising
> 70 = high risk for spontaneous bleeding
common with inherited bleeding disorders
what is normal INR and what do high/low values indicate
0.8-1.2
variability in normal range based on pathology
high values = increased bleeding/bruising
low values = increased clotting/VTE
> 5.5 = high risk for spontaneous bleeding
normal Creatine Kinase levels and contraindications if any
30-170
no direct contraindication; all symptom and medical stability limits
normal blood urea nitrogen levels and contraindications if any
10-20
no direct contraindication; all symptom and medical stability limits
normal creatine levels and contraindications if any
0.5-1.2
no direct contraindication; all symptom and medical stability limits
absolute contraindications to activity
new onset AFib
sustained VTach
complete heart block
increased PVCs (especially multifocal)
increased ventricular arrhythmias
new onset chest pain
uncontrolled arrhythmias causing hemodynamic instability or S&S
unstable angina
temporary pace maker
VTach storming
relative contraindications to activity
pending pacemaker interrogation
cardiac S&S
drop in HR with activity
drop in BP with activity
arrhythmias with rate control
Thrombocytopenia (platelets <50)
Anemia (Hgb <7)
Abnormal INR
pH is sensitive to what compounds that can alter blood gas levels
CO2 = controlled by lungs (respiratory); can be altered quick
HCO3 = controlled by kidneys (metabolic); cannot be altered quick
compensation = body is responding to abnormality
what happens with respiratory acidosis
hypoventilation
increase in CO2, decrease in pH
what happens with respiratory alkalosis
hyperventilation
decrease in CO2, increase in pH
what happens with metabolic acidosis
GI, endocrine, and renal dysfunction
decrease in both HCO3 and pH
what happens with metabolic alkalosis
renal/hepatic dysfunction, hypovolemia
increase in both pH and HCO3
