1. Classifications of Respiratory Failure
-
Hypoxemic Resp. Failure:
PaO2 < or equal to 50mmHg on an FIO2 > or equal to 60%
-
Hypercapnic Resp. Failure:
PaCO2 > or equal to 50mmHg with a pH < or equal to 7.25
-
Mixed Resp. Failure:
Combined Hypoxemic and Hypercapnic Resp. Failure (Respiratory aci
2. Goals and clinical conditions of mechanical ventilation as well as possible forego (futile) mechanical ventilation
- Increasing FRC
- Increase in compliance
- Decrease in total airway resistance
- Decrease RR and/or WOB
- Decrease PaCO2 (Hypercapnic Resp. Failure)
- Decrease O2 given
-
Withholding Mechanical Ventilation:
-
Birth Weight < 800g
- Severe ICH
- Hypoxic-is
3. Physical and Clinical signs of Hypoxemic Respiratory Failure
-
PaO2 < or equal to 50mmHg on an FIO2 > or equal to 60%
- SpO2 below 92% with supplemental oxygen and/or nasal CPAP
- Respiratory pattern (Ventilatory Status):
- PaCO2 < or equal to 30mmHg and pH > or equal to 7.50
-
Presentation:
- Agitated
- Cyanotic
-
3. Physical and Clinical signs of Hypercapnic Respiratory Failure
-
PaCO2 > or equal to 50mmHg with a pH < or equal to 7.25
-
Presentation:
- Appear to be Apneic
-
Listless (Lifeless; No movement)
- Cyanotic
- Tachycardic or Bradycardic
3. Physical and Clinical signs of Mixed Respiratory Failure
- Combined Hypoxemic and Hypercapnic Respiratory Failure
Side Note
: Respiratory Acidosis with Hypoxemia
- Patient will be Acidotic
(Listless; No movement)
4. CPAP: Initial settings, indications. In addition, what CPAP setting should you NOT exceed?
Initial:
-
4-5cmH2O
-
Increase in increments of 2cmH2O
SIDE NOTE
: NO higher than
10-12cmH2O
Indication:
-
Decreased FRC
- Infectious Process, Loss of lung volume, Inability for gas to reach alveoli, RDS, TTN (Transient Tachypnea of the Newborn)
-
Airway
4. CPAP: Contraindications
-
Upper Airway abnormalities
-
Choanal Atresia
: Bone obstruction in nasal cavity (Intubate)
-
Cleft Palate
: Split in the mouth (Intubate)
-
Tracheoesophageal Fistula (TEF)
DANGEROUS!!!
: A hole that connects the esophagus and trachea (Intubate)
-
Untrea
4. CPAP: Hazards
BE AWARE
- High pressures
- Decreased cardiac output
- Renal side effects
- Elevates ICP
- May cause pneumothorax
- Nasal obstruction
- Gastric distention
- Necrosis or erosion of the nasal septum
PSV (Pressure Support Ventilation)
Rarely used
- May be added to CPAP or SIMV
- Maintain spontaneous tidal volumes 5-8ml/kg
*Side Note: PSV + CPAP= BIPAP
Weaning
-
Down to 5cmH2O. Assess for possible extubation
Adjust PSV
- Adequate chest rise
- Adequate PaCO2
- Reduce grunting, nasal flar
SIMV
-
Set rate must be <30bpm
to be considered
partial ventilator support
-
Spontaneous breath may be considered CPAP
Side note:
- PC + SIMV for neonate
+ PIP 15cmH2O
Indication
- CPAP not tolerated
Hazards
- Increased Mean Airway Pressure (MAP)
Full ventilatory Support Modes
1. IMV and SIMV with
RR >30bpm
2. CMV
(Not preferable)
3. PCV - Plat > or equal to 35cmH2O or
PIP > or equal to 40cmH2O
-
May require to be sedated and paralyzed
-
Most of the time focused on PIP
Prefered Mode
4.
IRV - > or equal to 1:1
. Patient
must
be
Pressure Control Ventilation IRV
Goals
-
Increased RR
-
May add an inspiratory pause/hold
APRV (Airway Pressure Release Ventilation)
Goals
-
Restores FRC (Recruit Alveoli)
-
High level of CPAP
.
Side Note
: Bilevel = APRV+PEEP
MMV or AMV (Augmented Minute Ventilation)
Goals
-
Assist patient's minute ventilation to reach target during spontaneous breaths
-
Guillian-Barre
-
Myasthenia-Gravis
In the "Neonate World" Applying
8lpm
via Nasal prongs will deliver...
4-5cmH2O of PEEP
If a patient is in
Hypoxemic Respiratory Failure
...
CPAP
is the usually the mode of choice
EFF
-
E
xpiratory Pressure
(CPAP pressure)
-
F
IO2
-
F
low
CMV, IMV, SIMV
1. Sensitivity
2. Flow
3. Mandatory Rate Tidal Volume or I-Time
(I-Time X Flow = Vt)
4. FIO2
5. PEEP
PIP Initial setting...
15-20cmH2O
and adjust until good chest rise, auscultation and PaCO2
What affects the change of PaCO2?
- RR and PIP are the
main reason for the change of PaCO2
-
Side Note:
If Vt is not present on questions...
Look for Flow and I-Time
changing these setting
Directly Affects
Vt
(Tidal Volume)
EX)
Increasing Flow -> Increases Vt
Increasing I-Time -> Increase
RR - Neonates
30-40bpm.
May go up to
150bpm
RR - Pediatrics
Maintain PaCO2
of
40-48mmHg
Sensitivity - 3 Triggers
- Pressure
- Flow
- Volume
Pressure Trigger
-1 - -2cmH2O
Flow Trigger
0.15 - 1L/m
Volume Trigger
3.0 ml
PEEP
3-5cmH2O
FIO2
- Maintain
Pink Color
-
PaO2 > 60mmHg or SpO2 > 92%
Flow - Neonates
6-8L/m
- Excessive flow creates turbulent flow [Bronchospasms]
- Low flow will not inflate the lungs
[Vt = I-Time X Flow (sec)]
Flow - Pediatric
- Adjust to maintain
I:E of 1:2 - 1:4
-
Initial - 25-30lpm
*
Adjust flow
as needed - For
Good chest rise
and for a
sufficient amount of exhalation time.
I-Time - Pediatric
Adjust to maintain
1.0-1.5 sec
to maintain I:E of
1:2 - 1:4
Side Note:
Most of the time
1.0 sec
is generally used.
I-Time - Neonates
- Low Birth Weight
0.25 - 0.5 seconds
- Term
0.5 - 0.6 seconds
May need longer I-Times for RDS
Side Note:
Initial I-Time for Term Neonate
0.5 sec.
Inspiratory Hold used to detect...
Plateau Pressure
Expiratory Hold used to detect...
Auto-PEEP
Normal I:E Ratio for Neonates
*
1:1.5 - 1:2
Normal I:E Ratio for Pediatrics
**
1:2 - 1:4
Determining I:E Ratio
1.
Find TCT (Total Cycle TIme)
60/RR
2.
Finding E-Time
TCT - I-Time
3.
Finding Te/Ti
E-Time/I-Time
4.
Finding I:E Ratio
1:(Te/Ti)
Side Note:
1 : {[(60/RR) - I-Time] / Ti}
Flow Formula
Flow (L) = Minute Volume (Ve) X Sum of I:E
Side Note I:
If Vt and RR are
only
visible ->
Flow = (Vt X RR) X Sum of I:E
Side Note II:
If given Vt in ml and RR ->
Flow = [(Vt / 1000) X RR] X Sum of I:E
Finding Vt
Vt = I-Time X Flow (sec)
Normal Vt Ranges - Neonates
1. Term: 8-10ml/kg
(>2.5kg = >2500g = >5.5lbs)
2. Low Birth Weight: 6-8ml/kg
(<2.5kg = <2500g = <5.5lbs)
Very Low Birth Weight: 4-6ml/kg
(<1.5kg = <1500g = <3.3lbs)
Normal Vt Range - Pediatrics
8-10ml/kg
PC (Pressure Control)
Initial PIP = 15-20cmH2O
Initial RR = 30-40bpm
Corrected Vt
Set Vt - (PIP X 2)
Hazards of mechanincal ventilation
- Barotrauma
- BPD (Bronchopulmonary Dysplasia)
- Pneumothorax
- Hemodynamic Depression
- ROP (Retinopathy of Prematurity)
- ICH (Intracranial Hemorrhage)
- Hypoxic-Ischemic Injuries
Direct relationship:
a decrease of compliance
you will expect...
A decrease in chest wall excursion
Diminished
Compliance changed/decreased
Side note:
EX) Atelectasis, restrictive process (ARDS)
Rales/Crackles
1. Coarse
Rales/Crackles
-
Large Airway Secretions -> Suction
2. Medium
Rales/Crackles
-
Middle Airway Secretions -> CPT, PD&P
3. Fine
Rales/Crackles
(Moist Crepitant Rales)
Recommend Lasix + CPAP
- Fluid in the
Alveoli
-
CHF, Pulmonary Edema
Wheezing
-
Airway Narrowing
-
Increased in Airway Resistance (Raw)
-
Bronchospasm
Unilateral Wheezing
- Possible
Foreign Body Aspiration
Vesicular
-
"Bilateral Vesicular" = Normal Breath Sounds
Adventitious
Abnormal Breath Sounds
Side Note:
Adventitious isn't out of the ordinary but need more information on the patient. Nothing given read more thoroughly before considering "Normal
Percussion
1. Resonance - Normal air sound
2. Flatness - Atelectasis
3. Dullness - Pleural Effusion, Pneumonia
4. Hyperresonance - Increased air (Pneumothorax, Emphysema, Air-trapping)
Uncomplicated Hypoxemia
Easily corrected by delivering Oxygen to the patient.
Complicated Hypoxemia
Oxygen and Mechanical Ventilation is needed due to restrictive factors/perfusion/ respiratory abnormalities.
Tubing Factor
2ml/cmH2O
Optimal PEEP (AKA Cstat)
(Vt - (PIP X 2)) / (PLAT - PEEP)