Positioning: Nerve Injury

Question 1

How is the brachial plexus injured?

Answer 1

2nd most common injury

• any position
• when arm abducted >90 degrees or head turned away

Question 2

What happens when brachial plexus injured?

Answer 2

Thoracic outlet syndrome—> shoulder, neck, arm pain/numbness, impaired circulation

Question 3

How do you prevent a brachial plexus injury?

Answer 3

• axillary roll DISTAL to axilla
• pre anesthetic screen- ask pt if they can clasp hand behind head or can comfortably sleep with arms elevated overhead
• SpO2 on dependent arm in lateral position

Question 4

How is the ulnar nerve (brachial plexus) injured?

Answer 4

• • most commonly injured **
• compression between medial epicondyle of humorous and sharp edge of bed
• increased risk to men > 50 yrs, preexisting ulnar neuropathy,extremes of body habitus, prolonged hospital stay

Question 5

What does an ulnar injury present as?

Answer 5

Sensory loss to 4th and 5th digit

- claw hand- inability to abduct or oppose pinky

Question 6

How do you prevent injury to ulnar nerve?

Answer 6

In supine position: palm up in abducted, neutral at side, NEVER PALMS DOWN

Question 7

How is the radial nerve (brachial plexus) injured?

Answer 7

External compression of humoral head

• arms slip off table
• excessive cycling of BP cuff
• upper arm tourniquet
• sheets too tight around side tucked arms

Question 8

What is the consequence of a radial nerve injury?

Answer 8

Wrist drop

Question 9

What causes injury to the median nerve (brachial plexus)?

Answer 9

• IV in antecubital space
• carpal tunnel
• hyper extension of elbow

Question 10

How does a median nerve injury present?

Answer 10

• reduced sensation of palm, index, middle, lateral ring finger
• “ape hand”: inability to oppose thumb

Question 11

How is the femoral nerve (lumbar plexus) injured?

How can it be prevented?

Answer 11

Excessive traction during lower abdominal surgery

• avoid excess traction

Question 12

How does a femoral nerve injury present?

Answer 12

• impaired knee extension/hip flex ion

- reduced sensation over anterior thigh and anteromedial leg

Question 13

How is the saphenous nerve (lumbar plexus) injured?

How can this be prevented?

Answer 13

Compression of MEDIAL aspect of leg in lithotomy

-proper padding between TIBIA and stirrup

Question 14

What are the symptoms of a saphenous nerve injury?

Answer 14

Reduced sensation over anteromedial side of calf

Question 15

How is the obturator (lumbar plexus) nerve injured?

Answer 15

• excessive flexion of thigh toward groin

- excessive traction during abdominal surgery

Question 16

How does an injury to the obturator nerve present?

Answer 16

• impaired leg ADDuction

- reduced sensation over medial thigh

Question 17

How can an obturator nerve injury be prevented?

Answer 17

Minimize hip flexion

Question 18

What causes injury to the sciatic nerve (sacral plexus)?

Answer 18

• sitting position- sitting with straight legs

- lithotomy: extreme hip flexion and/or external rotation

Question 19

How does a sciatic nerve injury present?

Answer 19

• foot drop
• pain/numbness of leg, foot
• weakness of all skeletal muscle below knee
• diminished sensation over lateral half of leg and foot

Question 20

How can a sciatic nerve injury be prevented?

Answer 20

• ample padding under buttocks
• avoid excessive external rotation of hips
• flex table at knees

Question 21

What is the most frequently damaged nerve of the lower extremity?

Answer 21

• common peroneal nerve * (sacral plexus)

—> caused by compression of LATERAL aspect of leg in lithotomy

Question 22

How does injury to the common peroneal nerve present?

How can this be prevented?

Answer 22

Foot drop

• proper padding under FIBULAR head
• knees flexed with minimum rotation

Question 23

Crossing legs for extended periods increases risk of injury to which nerves?

Answer 23

• Sural nerve to top leg

- Superficial peroneal nerve to bottom leg

Question 24

What are the different stages of the brachial plexus and how many nerves are in each?

Answer 24

Roots (5–> C5-T1
Trunks (3)
Divisions (3)
Cords (3)
Branches (5)