MISC-positioning & nerve injury Flashcards
how does the T-burg position affect a pt position on the Frank-Starling curve
They shift right
If a pt has myocardial dysfunction, it can shift the too far right and affect CO
How does the sitting position affect cerebral perfusion pressure
If the head is higher than the heart, the CPP is lower
For every 20 cm above the heart MAP drops 15 mmHg
How much does MAP decrease in the brain with sitting position
It decreases by 0.75 mmHg for each cm change in height between the heart and reference point (head)
0.75 mmHg per 1 cm
What 4 body positions are associated with a higher incidence of hemodynamic instability under GA
- reverse T-burg
- sitting
- flexed lateral
- prone
How does anesthesia affect the following lung volumes or capacities
Tidal volume=
FRC=
Closing volume=
Tidal volume= DECREASED
FRC= DECREASED
Closing volume= INCREASED
How is the diaphragm affected with T-burg vs reverse t-burg positioning
t-burg = moves cephalad reverse = moves caudad
How are the following physiologic measures affected by t-burg positioning: pulm compliance= PIP = total lung vol = FRC =
pulm compliance= decreased
PIP = increased
total lung vol = decreased
FRC = decreased
How are the following physiologic measures affected by reverse t-burg positioning: pulm compliance= PIP = total lung vol = FRC =
pulm compliance= increased
PIP = decreased
total lung vol = increased
FRC = increased
How are the following ventilatory parameters altered in the dependent lung region: alveolar ventilation= alveolar compliance= PACO2 = PAO2 = V/Q=
alveolar ventilation= increased alveolar compliance= increased PACO2 = increased PAO2 = decreased V/Q= decreased (shunt)
How are the following ventilatory parameters altered in the NON-dependent lung region: alveolar ventilation= alveolar compliance= PACO2 = PAO2 = V/Q =
alveolar ventilation= decreased alveolar compliance= decreased PACO2 = decreased PAO2 = increased V/Q = increased (dead space)
How are the following pulmonary perfusion parameters altered in the dependent lung region: Blood flow= Vascular pressure= vascular resistance= V/Q=
Blood flow= increased
Vascular pressure= increased
vascular resistance= decreased
V/Q= decreased (shunt, zone 3)
How are the following pulmonary perfusion parameters altered in the NON-dependent lung region: Blood flow= Vascular pressure= vascular resistance= V/Q=
Blood flow= decreased
Vascular pressure= decreased
vascular resistance= increased
V/Q= increased (deadspace, zone 1)
How does positioning of the neck affect ETT tip position
flex = ETT tip towards carina (risk of endobronchial intubation)
extension = ETT tip towards VC (risk of extubation)
How does positioning of the carina affect ETT tip position
T-burg position can shift carina cephalad
-increases risk of endobronchial intubation
What 2 positioning measures of the head and body can increase the risk of endobronchial intubation
- flexion of the neck
2. t-burg positioning
3 positioning factors that can increase airway edema
- prone/t-burg increase hydrostatic pressure
- neck flexion impairs venous drainage
- excess airway equipment impairs lymphatic drainage
When concerned about airway patency following extubation, what can be done to assess for readiness
perform leak test to assess air movement around the ETT
DL to visually inspect larynx
When positioning UE, what decreases risk of stretch injury of the brachial plexus
- ABduction of arms <90*
2. NOT rotating the head away from either side
What 2 positioning measure increase risk for brachial plexus compression injury
- shoulder compression
2. axillary roll in the axilla (not under chest)
How does arm abduction >90* increase risk of brachial plexus injury
It increases stretching of the brachial plexus around the head of the numerus
How does head rotation increase the risk of brachial plexus injury
Rotation of head can cause stretching injury on the contralateral side
How should shoulder braces be positioned to decrease risk of brachial plexus injury
placed at DISTAL end of each clavicle over the acromion
How should legs be positioned in the lateral decubitus position to prevent nerve injury
- down leg is flexed and padded (prevent common perineal n. injury)
- up leg is extended and pillows placed between legs
Where are safety straps placed in the lateral decubitus position
- between iliac crest and femur head (NOT over the femur head)
- over the thorax or shoulders
