-
Supine - cardiovascular
minimal
-
Supine - pulmonary
minimal unless large belly - then it will decrease FRC
-
Supine - injury
- ulnar nerve
- pressure alopecia
- back ache
-
How should the arms be positioned while supine?
- less than 90 degrees abduction
- hand/forearm supinated/neutral
-
What are two variations of supine?
frog leg, lawn chair
-
Trendelenburg - cardiovascular
increases venous return
-
Trendelenburg - pulmonary
decreases FRC and lung compliance
-
Trendelenburg - injury
brachial plexus if shoulder braces are used, increased ICP/IOP, facial and airway swelling, aspiration
-
Reverse Trendelenburg - cardiovascular
decreased venous return = decreased BP
-
Reverse Trendelenburg - injury
decreased cerebral perfusion
-
Lithotomy - cardiovascular
increased preload (d/t leg elevation)
-
Lithotomy - pulmonary
decreased lung compliance, decreased Vt
-
Lithotomy - injury
- Common Peroneal nerve,
- increased ICP,
- potential torsion of lower spine,
- lower extremity compartment syndrome (increased with long surgery time)
-
Lateral Decubitus - cardiovascular
increased pulmonary blood flow to dependent (under ventilated lung) = VQ mismatch
-
Lateral Decub - Pulmonary
- VQ mismatch - worsened with one lung ventilation for lung surgery
- Decreased compliance and FRC of dependent lung
-
Lateral Decub - injury
brachial and ulnar nerve injuries from pressure points
-
Prone - cardiovascular
maintained if abdomen hanging freely
-
Prone - pulmonary
ok if abd hanging freely
-
Sitting - cardiovascular
- risk of air embolism (dural venous sinuses)
- significant hypotension when being placed in position
-
Sitting - pulmonary
benefits: improved ventilation, access to airway
-
Ways peripheral nerves are damaged:
- compression
- stretch
- ischemia
- metabolic derangement
- direct trauma/laceration
-
Where does the ulnar nerve originate?
C8-T1 root
-
Ulnar nerve damage symptoms:
- inability to abduct or oppose 5th finger
- decreased sensation of 5th and 1/2 of 4th finger
- atrophy --> claw hand
-
How to prevent ulnar nerve damage?
maintain arm supinated/neutral
-
Brachial Plexus cause:
- > 90 degrees abduction of arm
- lateral rotation of head
- asymmetric retraction of the sternum
- direct trauma
-
Radial Nerve Injury symptoms:
- wrist drop
- inability to abduct the thumb or extend the metacarpophalangeal joints
-
Median Nerve Injury caused by:
AC fossa IV insertion
-
Median nerve injury symptoms:
Inability to oppose 1st and 5th finger, decreased sensation over the palmar area
-
Sciatic and Common Peroneal Nerve symptoms
- foot drop
- inability to extend toes in dorsal direction
- inability to evert the foot
-
Femoral neuropathy symptoms:
- decreased flexion of the hip
- decreased extension of the knees
- loss of sensation over superior thigh
- loss of sensation over medial/anteromedial leg
-
Obturator neuropathy symptoms:
- inability to adduct the leg
- decreased sensation over medial thigh
-
What increases your risk for ION and CRAO?
- prolonged hypotension
- long duration in prone position
- large blood loss
- large crystalloid use
- anemia/hemodilution
- increased IOP/ICP
|
|
