oxyhemoglobin dissociation curve
shift to right
Caused by high temp, low pH, high PCO2, high DPG production
acidosis
Less affinity for O2
releases more readily
release o2, but Hemoglobin less likely to pick up o2
oxyhemoglobin dissociation curve
shift to left
Caused by high pH, low temp, low PCO2, fatal hemoglobin, low DPG production
alkalosis
Greater affinity for o2
hoLds the o2
hemoglobin picks up o2, but does not release o2
Dead Space Unit
examples
normal ventilation, no perfusion (blood clot)
Air in alveoli, no blood flow to alveoli
No gas exchange
i.e PE, cardiogenic shock
shunt unit
examples
No ventilation, normal perfusion - Potential Causes: pneumonia, tumor, fluid, not breathing, anything blocking ventilation, pulmonary edema
No air, yes blood flow
silent unit
no ventilation, no perfusion
No blood flow or air
Fix underlying problem
Dead p much
Supplemental o2 wouldn't really work
respiratory acidosis
low pH, high Paco2
A drop in blood pH due to hypoventilation (too little breathing) and a resulting accumulation of Co2.
hypoventilation, PE, CNS depression
i.e COPD
respiratory alkalosis
high pH, low Paco2
Arise in blood pH due to hyperventilation (excessive breathing) and a resulting decrease in CO2.
hyperventilation, anxiety
metabolic acidosis
low pH, low HCO3
decreased pH in blood and body tissues as a result of an upset in metabolism
renal failure, DKA, anaerobic metabolism (shock)
kussumal respiration (hyperventilaiton)
metabolic alkalosis
high pH, high HCO3
excessive bicarb administration, acid deficit (vomiting or NGT suction)
rare
Fully compensated
pH normal
PaCO2 & HCO3 abnormal
Partially compensated
A pH level that is abnormal.
all 3 values abnormal
Uncompensated
pH and one other value is abnormal
oxygenation failure (gas exchange)
Chest pressure changes are normal in air move in and out without difficulty but does not oxygenate the blood sufficiently
It occurs in the type of V/Q mismatch in which air movement in oxygen intake (ventilation) are normal but lung blood flow (perfusion)
ventilatory failure (hypercapnic)
which blood flow (perfusion) is normal but air movement (ventilation) is inadequate. It occurs when the chest pressure does not change enough to permit air movement into and out of the lungs. As a result, too little oxygen reaches the alveoli, and carbon
2 of biggest signs of respiratory failure
restlessness and agitation (mental status change)
why is low Co2 indicator of sepsis
build up of lactic acid will lead to person to hyperventilate,which takes less time for gas exchange to happen, less CO2 out
amount of oxygen being delivered�room air is 21%--this setting can range from 21%-100%
fi02
volume of gas delivered in one ventilatory cycle�normally 7 mL/kg
tidal volume
minimal number of breaths per minute
rate
rate at which tidal volume is delivered�measured in L/min
flow rate
negative pressure a patient must generate to trigger the ventilator to deliver a breath
sensitivity
ventilator will not exceed this pressure to avoid barotrauma�pop off mechanism
high pressure limit
used to decrease patient's work of breathing
pressure support
positive pressure left in lungs at the end of expiration to prevent atelectasis
Positive end-expiratory pressure (PEEP)
used for patients without any spontaneous respiratory effort (rarely used)
control ventilation
delivers gas at predetermined volume in response to patient effort�if no effort is made after a certain period of time, ventilator will deliver a breath
assist-control ventilation
most common
delivers preset volume and rate but allows for independent spontaneous breaths�synchronized with pt effort�useful for weaning
Synchronized intermittent mandatory ventilation (SIMV)
allows pt to take own breath
put on this to determine if can be taken off ventilator
when can VAP develop
w/in 48 hrs of intubation
VAP prevention bundle
Elevation of the HOB between 30 and 45 degrees
- secrete drainage
Daily "sedation vacations" to assess readiness to extubate
Peptic ulcer disease prophylaxis
DVT prophylaxis
diffuse inflammatory response from massive insult to body
A disorder of the lung tissue caused by infection, shock, burns, or other insults in which the capillaries became leaky and the air spaces fill with fluid.
ARDs
Myocardial infarction common cause
Pump is not effective
Results in ineffective tissue perfusion
Presents with hypotension, bradycardia (typically), and follows a cardiac event or injury
Treatment?
cardiogenic shock
fix MI, reestablish perfusion to cardiac muscles
Loss of circulating volume
Results in ineffective tissue perfusion
Presents with hypotension and tachycardia, typically following an event that would cause loss of volume
tx?
hypovolemic shock
replace volume, blood transfusion, infusion
Loss of sympathetic tone following acute spinal cord injury
Extensive vasodilation
Presents with hypotension and bradycardia following neuro trauma
Treatment?
neurogenic shock
start w fluid, vasopressors, other interventions to increase HR
sepsis
s/s
lab values
fever
hypotension, tachy, hypoxic, changes in mentation, tachypnea
increased WBC, lactate
fever not necessarily; no fever means their compensatory method not working
sepsis tx bundle
not in order
* give 100% oxygen via non-rebreather mask.
* obtain two separate blood cultures before antibiotic therapy is initiated.
* initiate antibiotic therapy.
* initiate fluid resuscitation.
* measure the patient's lactate. Septic shock is diagnosed
Phlebostatic axis (4th intercostal space)
Relevel if pt position is changed
Zero at the beginning of the shift and if the values do not fit the clinical picture
zeroing
Measures blood pressure with each heart beat
Most common site is the radial artery
Need to perform Allen's test
arterial pressure monitoring
Normal Central Venous Pressure (CVP)
2-6 mmHg
normal Pulmonary Artery Wedge Pressure (PAWP)
6-12 mm Hg
what do you do if you have no pulse
examples
defib
vtach w no pulse
Vfib
what do you do if you have a pulse
cardioversion
repetitive firing of irritable ventricular ectopic focus, usually at 140-180 beats/min
V tach
answer A
result of electrical chaos in ventricles
quivering
no pulse
v fib
START CPR
complete absence of any ventricular rhythm
ventricular asystole
flat line
CPR
microbial infection involving the endocardium
endocarditis
risk factors
IV drug abuse
valve replacement recipients
systemic infections
structural cardiac defects
endocarditis
inflammation of pericardium
pericarditis
acute compression of the heart due to the accumulation of fluid within the pericardial cavity
cardiac tamponade
Pericarditis S/S
Radiating chest pain
often relieved by sitting up or bending for ward and worsened by lying down or breathing in and
friction rub
Beck's triad for cardiac tamponade.
(1) HYPOTENSION
(2) MUFFLED or DISTANT HEART SOUNDS
(3) JUGULAR VENOUS DISTENSION (JVD)
***Physical Exam: Tachycardia, Hypotension+++, PULSUS PARADOXUS (? in systolic BP on inspiration >10mm Hg).
Tx: PERICARDIOCENTESIS
common symptoms of oxygenation failure
Hyperventilation, anxiety
ABGs oxygenation failure
� no change in CO2 or pH
� only change will be in oxygenation: saO2 and paO2 will decrease
common symptoms of ventilatory failure
restlessness, irritability or agitation, confusion, and tachycardia
can go into coma
ABGs ventilatory failure
� high CO2 and low pH
� saO2 and paO2 will decrease
Endotracheal tube insertion 8 steps
Preoxygenate Lay patient flat
Medicate patient with sedatives and paralytics
Continue to ventilate patient
Provide cricoid pressure
Assess placement by auscultating
Inflate balloon with air
Secure tube
Confirm w x-ray