What is the single most important indicator in critical illness?
tachypnea
Beck's Triad
hypotension, JVD, muffled heart sounds
- a/w cardiac
... [Show More] tamponade
What is the thyromental distance?
It is the distance in finger breadths between the anterior prominence of the thyroid cartilage (adam's apple) and the tip of the mandible (chin). It is an estimate of the length of the mandible and the available space anterior to the larynx
What does it mean when the thyromental space is < 3 fingerbreadths?
- approx 6 cm
- indicates the larynx might be more anterior and therefore difficult to visualize during laryngoscopy
** a more acute angulation of the stylet at the distal end of the endotracheal tube may be helpful.
Patient is apneic w/ a pulse. What do you do?
Bag them.
- One handed bag compressions should be delivered 10-20 times per min. Each compression should take place over 1 second.
** If patient starts spontaneously breathing, try to be synchronous with their respiratory efforts.
** If/once the patient is breathing easily and adequate Vt are being inhaled, enough to produce minute ventilation, stop bagging.
What is the goal of manual mask ventilation?
to provide adequate minute ventilation: the product of the tidal volume delivered during each resuscitation bag compression and the number of compressions per min.
** The total gas volume within most adult resus bags is 1 to 1.5 LITERS
Bag mask should be connected to ________% oxygen and flow at a rate of _______
100% oxygen at a rate of 15L/min
HFNC
- Uses up to 100% oxygen source
- Provides higher amounts of FIO2 (0.32-1.0) in patients with high minute ventilation requirements by matching patient's inspiratory demands and minimizing air dilution
- These devices also can generate PEEP (that is difficult to measure; can cause barotrauma in theory)
- Flow rates up to 60L/min
- heated and humidified oxygen
NRB
- AKA Reservoir Face Mask
- Bag is filled with 100% oxygen from a supply source (tank)
- The flow rate must be adjusted so that the bag remains completely or partially distended throughout the respiratory cycle
- When the mask is properly applied, oxygen delivery can be maximized but rarely exceeds a FIO2 of 0.6 to 0.9
- One way flap valves minimize entrapment of room air which dilutes FiO2
- NRB is a high oxygen high, flow device.
- non humidified oxygen
** commonly used to improve oxygenation in patients with severe hypoxemia until further eval and treatments are accomplished.
Aerosol Face Mask
- This mask has large side holes, the mask itself is attached to large bore tubing to a nebulize that blends 100% oxygen and room air to deliver a PRESET FIO2 level (done by dial on oxygen adapter)
- If the entire aerosol mist disappears from the mask during. inhalation, the patient's inspiratory flow demands are probably exceeding the capacity of the nebulizer and room air is being entrained.
- minimum flow rate = 8L/min
- Max FIO2 = 40-60%
- This is a variable oxygen, moderate-flow device.
Simple Face Mask
- minimum flow rate: 6L/min (to clear CO2 from mask)
- humidified O2
- Approx. concentrations L to FIO2 ratios:
6L = 40%
7L = 50%
8L = 60%
Venturi Face Mask
- aka air entrainment face mask
- delivers O2 through a jet mixing device that increases the velocity of oxygen and causes a controlled entrainment
- the FiO2 can be more precisely controlled from .24 to .5 (24% to 50%) at high flow rates simply my selecting the interchangeable nozzle and adjusting the O2 flow rate
- this is a high flow, controlled oxygen device.
Nasal Cannula flow rate to FIO2 estimates if RR and tidal volumes are normal
1L = 24%
2L = 28%
3L = 32%
4L = 36%
5L = 40%
6L = 44%
NPPV uses two levels of positive airway pressure, combining modalities of pressure support ventilation and what?
CPAP
What is CPAP?
continuous positive airway pressure
- Allows spontaneous breathing from a gas source at an elevated baseline system pressure (higher than atmospheric pressure)
- Functionally equivalent to PEEP.
By convention, PSV mode is referred to as _______ and CPAP is referred to as _______ when talking about NPPV/BIPAP
PSV = IPAP
CPAP = EPAP
The difference between these two numbers determines the tidal volume generated.
Initiation of NPPV guidelines
- Do not delay intubation if needed and keep in mind the patient’s resuscitation status.
- Consider ABG analysis prior to initiation.
- Explain the procedure.
- Keep head of bed at ≥45°.
- Ensure appropriate mask or helmet size.
- Assess the patient’s tolerance of the mask by applying it by hand before securing the harness.
- Adjust the difference between EPAP and IPAP to achieve and effective VT and CO2 clearance. Adjust EPAP for alveolar recruitment in increments of 2 cm H2O per step to improve oxygenation. Depending on the ventilator, a similar increase in IPAP may be required to maintain the same VT.
- If assist-control volume ventilation is used, begin with a VT of 6 to 8 mL/kg (depending on the underlying pulmonary condition).
- Titrate pressures, volume, and FIO2 to achieve appropriate pH, PaO2, and PaCO2 levels. Ventilator changes can be made every 15 to 30 minutes.
- Follow vital signs, pulse oximetry, mental status, clinical appearance, and ABG (if indicated).
- Remember that goals of NPPV may include a respiratory rate <30 breaths/min, VT >7 mL/kg of predicted body weight, improved gas exchange, and patient comfort.
- It is also important to be cognizant that IPAP > 20 cm H2O may lead to gastric distension.
What are the goals of NPPV?
The goals of NPPV may include a
- respiratory rate <30 breaths/min
- VT >7 mL/kg of predicted body weight
- improved gas exchange
- patient comfort.
Initial NPPV settings
Use the following initial ventilator settings:
- Mode: Spontaneous
- Trigger: Maximum sensitivity
- FIO2: 1.00
- (PEEP) EPAP: 4-5 cm H2O
** (higher levels are poorly tolerated initially)
- (PSV) IPAP: 10-15 cm H2O
- Backup rate: Start at 6/min
CPAP indications, pros, cons
- CPAP alone can also be delivered noninvasively but does not provide support of ventilation.
- CPAP allows spontaneous breathing from a gas source at an elevated baseline system pressure (higher than atmospheric pressure) and is functionally equivalent to positive end-expiratory pressure (PEEP).
- uncomfy
- primarily used to treat OSA [Show Less]