Critical Care Flashcards
Review the mnemonic for RSI.
SOAPME
- S: suction
- O: oxygen
- A: airway (ETT in expected size and one smaller, stylet, syringe, laryngoscope) and alternative airways (mask and bag)
- P: position patient (end of bed, sniff position, towel roll)
- M: medications (sedative like ketamine, paralytic like rocuronium, and post-sedation like propofol) and monitors (telemetry, pulse-ox)
- E: EtCO2 sensor
- Make sure RT is present and ventilator is ready
What ABG findings are suggestive of impending respiratory failure in an asthma attack?
Hypoxemia and hypercarbia
What are the three reasons intubation worsens hypotension?
- Positive-pressure ventilation decreases RV filling
- Vagal response
- RSI meds
How does pulse oximetry work?
Pulse-ox devices shine a red light and an infrared light through a part of tissue. Oxygenated blood absorbs a lot of red light but not much IR light. Deoxygenated blood does not absorb much of either IR or red light. By comparing these you can get a sense of what part of hemoglobin is oxygenated.
It also uses Beer’s law and Lambert’s law.
Beer’s law states that absorption of light is proportional to the concentration of a substance.
Lambert’s law states that the absorption is proportional to the distance traveled through a substance. Because the distance traveled through tissue changes ever so slightly with pulsations, you can calculate the arterial component of blood.
This is calibrated on healthy volunteers breathing diluted oxygen mixtures.
What does the PI next to the plethysmography graph stand for?
Perfusion index
This is a measure of the signal strength.
___________________ is a more accurate spot to obtain SpO2 in vasoconstricted states.
The ear or forehead
Pulse oximeters are not reliable in which patients?
Those with non-pulsatile flow: ECMO and LVAD patients.
Pulse oximeters have what lag time?
5-15 seconds
How can you identify a vasodilated state on plethysmography?
A steep upslope, a tall peak, a steep downslope, a long PTT, and a high PI indicate a vasodilated state.
What is the pulse transit time?
It’s the time from R-wave peak (systole) to the next plethysmography peak, which physiologically is the time it takes blood to get from the heart to the tissues.
A long PTT indicates a vasodilated state.
What is hypoxia and hypoxemia?
- Hypoxia: insufficient oxygen delivered to tissues
- Hypoxemia: insufficient oxygen in blood
What are the five causes of hypoxemia?
- Low partial pressure of inspired oxygen (such as from going up in altitude)
- Low alveolar ventilation (drug overdoses, CNS injury, neuromuscular problems, and chest wall stiffness)
- Diffusion limitations (pulmonary edema, pulmonary fibrosis)
- V/Q mismatch (obstructive lung diseases, pulmonary emboli)
- Shunt (cardiac defects, AVMs, severe pulmonary disease where blood is not oxygenated)
Increased A-a gradient that does not normalize with supplemental O2 is _______________.
shunt
Diffusion limitations and V/Q mismatch will normalize. Decreased partial pressure of O2 and decreased ventilation will have normal A-a gradients.
Volume control mode is also called ______________.
assist control volume (AC-VG)
Pressure control mode is also called ______________.
assist control pressure (AC-PC)
If you’re setting volume (say, in volume control AC-VG mode), what are typical tidal volumes?
400-500 mL
What are rise time and inspiratory time?
Inspiratory time is the time that a breath is delivered over. Rise time is the time it takes the ventilator to achieve the peak pressure. Because of this, rise time is only on PC modes.
What is PRVC?
Pressure-regulated volume control
This is a mode in which you set a tidal volume and a maximum pressure. It tries to achieve the TV but has a pop off pressure to avoid barotrauma.
Explain the settings in SIMV-PS.
- RR: this is the rate of breaths that are fully ventilated (i.e., not PS breaths). The patient will get all of these breaths directed by your settings (PC or VG), and then they can get any additional breaths on top of this rate guided by the PS settings.
- PC/VG: you can have either mode in SIMV. This will be the settings for the RR breaths – not the PS breaths.
- PS: this is the pressure support that the patient will get for the breaths they initiate on top of their RR. It is written as the additional pressure they get on top of PEEP. So if the PIP of their RR breaths is 22 and they have a PEEP of 8, then they would need a PS of 14 in order to get the same inspiratory pressure during PS breaths.
- PEEP: same as always
- FiO2: ditto
Review the flow rates of these access types:
- Triple lumen catheter (with 16 gauge x1 and 18 gauge x2)
- 18 gauge IV
- Cordis (8.5 Fr)
- 16 gauge IV
- Triple lumen catheter (with 16 gauge x1 and 18 gauge x2): ~7 L/hr
- 18 gauge IV: 6.0 L/hr
- Cordis (8.5 Fr): 7.6 L/hr
- 16 gauge IV: 13.2 L/hr
In which patients is therapeutic hypothermia least helpful?
- PEA arrests
- Brain bleeds
- Significant trauma
- Hypotensive despite pressors
- Pediatric patients
Sepsis resuscitation fluids are _______ mL/kg.
30
Review the 1-hour sepsis bundle items.
Orderset: ED Adult Sepsis
- Lactate
- Blood cultures
- Broad-spectrum antibiotics
- Fluids for hypotension or lactate > 4
- Vasopressors if hypotensive or elevated lactate after 30 mL/kg fluids
You must remeasure lactate in sepsis if it is greater than ________.
2
Review the new diagnosis fo sepsis (from the 2016 Surviving Sepsis Campaign).
A life-threatening organ dysfunction caused by a dysregulated host response to infection
Organ dysfunction can be identified as an acute change in total SOFA score ≥2 points consequent to the infection.
The baseline SOFA score can be assumed to be zero in patients not known to have preexisting organ dysfunction.
A SOFA score ≥2 reflects an overall mortality risk of approximately 10% in a general hospital population with suspected infection. Even patients presenting with modest dysfunction can deteriorate further, emphasizing the seriousness of this condition and the need for prompt and appropriate intervention, if not already being instituted.
What level of hypotension triggers the fluid indication in the sepsis bundle?
Two reliable* BPs w/ MAP < 65
- This means values that you trust and that are new for the patient. If a patient is always low then document it.
Why is the sepsis bundle important to complete?
Studies have shown that patients who complete the sepsis bundle have a significant improvement in mortality.
If you reach ___ mcg/min of norepinephrine, consider starting a second pressor (typically vasopressin).
5
If a patient is having clinically important tachyarrhythmias on norepinephrine or epinephrine, consider switching to _______________.
phenylephrine
For CMS compliance with sepsis, you only need to document _______________.
that you examined the patient, what weight you used for IV fluids, and the post-fluids exam
Also, document why you deviated from protocol in your MDM (such as why antibiotics were given after before cultures or why fluids were not per protocol)
What should you document for sepsis patients?
Go to the sepsis tab (in the bar with Study Review, Care Everywhere, etc.) and then type .sepsisexamtotal to pull the flowsheets into your MDMD.
If you don’t want to use the navigator, you can also use the .uncmcsepsisexam dot phrase in your note.
If you are struggling to ventilate a patient, then consider _______________.
paralysis
Review the mnemonic for hypoxia in intubated patients.
If your intubated patient becomes hypoxic, don’t be a DOPE:
- Dislodgement of the tube (check for a change in depth, bilateral breath sounds, capnography, and consider a CXR)
- Obstruction (suction for secretions)
- Pneumothorax (listen for bilateral breath sounds, check a CXR)
- Equipment failure (check the pulse ox, circuit tubing, and ventilator)
__________ is first-line for cardiogenic shock, septic shock, and neurogenic shock.
Norepinephrine
Epinephrine is first-line for which type of shock?
Anaphylactic
What is the dose of norepinephrine?
1-30 mcg/min
Some places do weight-based dosing.
Neosynephrine is which pressor?
Phenylephrine
Which pressor has no extravasation risk?
Phenylephrine
It can actually be given subcutaneously.
________________ can vbe given if other pressors are causing significant arrhythmias.
Phenylephrine (Neosynephrine)
What are pressor doses of dopamine?
5-10 mcg/kg/min for beta targeting
10-20 mcg/kg/min for alpha targeting
Which pressor is not titratable?
Vasopressin
It is standard to be 0.03 units/minute. UNC used to be 0.04 units/minute but recently switched.
Which receptor does vasopressin act on to increase BP?
V1
Remember the “V2 is tubules”.
The highest extravasation risk pressor is ___________.
vasopressin
You need a central line to give this.
Dopamine’s brand name is __________.
Intropin
What is the shock index?
Shock index is HR/SBP. This value in healthy people is < 0.9. If it is greater than this it can indicate shock.
What are the two types of heat stroke?
Exertional and non-exertional
Exertional heat stroke is the classic young athlete or military cadet who overexert themselves in extreme heat.
Non-exertional heat stroke is typically seen in people with comorbitidies that prevent them from escaping heat (think old demented lady in non air conditioned place or young child in a car).
How should you assess treatment of heat stroke?
The patient’s GCS should improve rapidly with cooling. If they don’t then think of something else.
True or false: you should correct heat stroke to normal temperature.
False, just get it to lower fever levels, like 101
How can you treat heat stroke if it fails cold rags, ice packs, misting?
Body bag full of ice
A key clinical finding of heat stroke is ________________.
AMS