Principles Test 3- Positioning

Front 1

Blunted or obtunded _____ prevent patients from repositioning themselves for comfort (i.e. leg going numb)

Back 1

reflexes

Front 2

Anesthesia may blunt compensatory _____ reflexes that would minimize systemic BP changes w abrupt position changes (Sitting to supine).

Back 2

sympathetic nervous system

Front 3

Rendering patients unconscious and relaxed may permit placement in position they may not have normally ____ in an awake state

Back 3

tolerated

Front 4

This is not a standard or guideline, but provides an analysis of expert and practitioner opinion and is intended to assist decision-making areas of patient care where strong scientific evidence is currently lacking

Back 4

practice advisory for prevention of peri-operative peripheral neuropathies

Front 5

Preexisting pt attributes assoc w incr incidence of perioperative neuropathies

Back 5

extreme of age or body wt, preexisting neuro symptoms (cubital tunnel entrapment from occupational trauma, hip problems, shoulder injury, neck ltd ROM), DM, PVD, etoh, smoking, arthritis

Front 6

What are the common surgical positions?

Back 6

supine
prone
lateral decubitus (decub is side touching OR table)
lithotomy
trendelenberg/reverse trend
jack knife
sitting

Front 7

What are the primary mechanisms responsible for nerve injury?

Back 7

transection, compression, stretch, kinking

Front 8

Transection occurs as a result of

Back 8

surgical maneuvers or trauma

Front 9

Compression occurs as a result of

Back 9

nerve being forced against a bony prominence or a hard surface such as an arm board or OR table

Front 10

Stretch/traction injuries occur as a result of

Back 10

nerves (such as sciatic or brachial plexus) undergo conduction changes, axonal disruption, or interruption of nerve's vascular supply

Front 11

Kinking injuries occur as a result of

Back 11

a peripheral nerve getting pinched between 2 immovable structures

Front 12

____ is a common component of all peripheral nerve injuries

Back 12

ischemia

Front 13

Causes of peripheral nerve injuries

Back 13

occlusion of major vessels, emboli, tissue edema, inhibition of perfusion at the capillary level

Front 14

This is the most common surgical position

Back 14

supine

Front 15

Cervical, thoracic, lumbar vertebrae should be in a straight horizontal line in this position

Back 15

supine

Front 16

This position has minimal effects on circulation,FRC is decreased 25-30%, (Further decreased by NMBs), and adverse effects may be offset by mech ventilation

Back 16

supine

Front 17

other name for supine position

Back 17

dorsal recumbent

Front 18

In supine position, legs should not be _____, head should be in a ___ position and supported, and heels should be ___.

Back 18

crossed, neutral, padded

Front 19

What is the ideal position for the supine safety strap

Back 19

2" above knee

Front 20

You should ensure and chart that arm boards and arms are in less than a ___ degree abduction angle, optimal is ____ Degrees.

Back 20

90, 60

Front 21

If arms are abducted >90 degrees,

Back 21

stretches subclavian and axillary vessels resulting in radial pulse obliteration and arterial thrombosis

Front 22

in supine position, _____ relieves pressure on the ulnar nerve as it passes through the humeral notch at the elbow

Back 22

palms up supination

Front 23

Supination of the elbow may be a catch 22 because

Back 23

it may incr stretch on the brachial plexus (C5-T1)

Front 24

In supine position, when hands are pronated it is best to ____ the arms to decrease pressure on the ulnar nerve

Back 24

adduct

Front 25

Because abduction of the arms even less than 90 degrees can still cause pressure on ulnar groove during pronation, the provider should

Back 25

pad around the ulnar groove

Front 26

In supine position, extreme rotation of the head can cause

Back 26

occlusion and thrombosis of the vertebral artery

Front 27

Supine pressure on the occiput of the head could lead to

Back 27

focal alopecia

Front 28

Relaxation of the paraspinous muscles and flattening of the normal lumbar convexity during supination results in

Back 28

tension on the interlumbar and lumbosacral ligaments causing backache

Front 29

Pressure from the face mask or head strap could cause injuries of

Back 29

the supraorbital and facial nerves

Front 30

Pressure of face mask on buccal branch of the facial nerve results in paralysis of

Back 30

the obicularis oris muscle

Front 31

The facial nerve is at risk from the anesthetists fingers on the patients mandible during

Back 31

mask ventilation

Front 32

Face check should be completed and documented every

Back 32

15 minutes

Front 33

5 branches of the facial nerve, top to bottom

Back 33

temporal, zygomatic, buccal, mandibular, cervical

Front 34

When arms need to be adducted for certain cases, the palms should face

Back 34

outer thigh
"attention position"

Front 35

Extreme head rotation can result in

Back 35

decreased cerebral venous drainage and cerebral blood flow

Front 36

Prone/jack knife position is good for

Back 36

rectal surgery

Front 37

In the prone position, induction is completed on _____, then pt is ____ to OR table under command of ___.

Back 37

stretcher, logrolled, CRNA

Front 38

Type of table for prone cases

Back 38

jackson frame or wilson table

Front 39

During pronation, neck should be in allignment w

Back 39

spinal column

Front 40

____ and ____ must be protected in prone position to avoid compression

Back 40

eyes and ears

Front 41

In prone position, chest rolls or bolsters are placed lengthwise on thorax extending from ____ to _____ to ensure adequate lung expansion and diaphragm excursion.

Back 41

acromioclavicular joints to iliac crest

Front 42

You must ___ and ____ the eyes during general!

Back 42

tape and lube

Front 43

Increased intraocular pressure is seen in what positions?

Back 43

prone, trendelenberg, lateral decub

Front 44

Reduction in ocular perfusion pressure increases with

Back 44

length of time in a surgical position that raises IOP

Front 45

Whats the best way to prevent incr IOP resulting in decr OPP?

Back 45

return pt to supine position for 5 min q1hr to help prevent post op vision loss

Front 46

What do you do w the arms of a prone pt?

Back 46

arms at side or extended alongside head on armboards like superman

Front 47

What must you document for prone patients

Back 47

pressure points padded, free abd and chest expansion, position of arms, eye care

Front 48

Turning pts head during pronation could lead to

Back 48

obstructed jugular venous drainage, vertebral artery occlusion, post op neck pain

Front 49

most common head position for prone pt is

Back 49

face down w prone pillow -- keep OETT easily accessible and unobstructed!

Front 50

Cardiac considerations of prone patient

Back 50

pooling of blood in extrem, compression of abdominal muscles, decr preload/CO/BP, incr SVR/PVR, use teds and scds!

Front 51

Respiratory considerations of prone patient

Back 51

decr lung compliance, incr PAWP, incr WOB, thoracic outlet syndrome, ETT dislodgement and accidental extubation

Front 52

This syndrome is secondary to thoracic nerve compression, agonizing, debilitating, and unremitting pain post-op following overhead arm placement

Back 52

thoracic outlet syndrome

Front 53

In classic trendelenberg, the head is ___ and knees are ____.

Back 53

down, flexed

Front 54

Trend is used in _____ procedures

Back 54

shock, trauma, GYN/lower abdominal

Front 55

You should only start w a trend position of ____ Degrees, and only go into steep trend w frequent requests.

Back 55

10-15 degrees

Front 56

There is increased _____ force in the trend position.

Back 56

visceral

Front 57

Trend allows for lower _____ surgery, gives good access to head and arms, and displaces abdominal _____, pushing diaphragm against the heart, leading to ____ stroke volume.

Back 57

abdominal,
viscera,
decreased

Front 58

Trend accentuates the compressing of the ____ by the abdominal viscera.

Back 58

lung bases

Front 59

Cardiac effects of trendelenberg

Back 59

activation of baroreceptors, decr in CO, PVR, HR, and BP,
does not improve CO in hypotension and hypovolemia

Front 60

Respiratory effects of trendelenberg

Back 60

decr FRC, total lung capacity, and pulm compliance secondary to shift of abd viscera,
incr VQ mismatching,
atelectasis,
incr likelihood of aspiration, incr WOB

Front 61

It may be difficult to ventillate trend patients due to higher ____ pressures

Back 61

inspiratory

Front 62

Trend puts pt at risk for OETT displacemen due to

Back 62

cephalad shift of the mediastinum

Front 63

Trend promotes ____ swelling

Back 63

facial/airway

Front 64

Because venous return increases, trend may mask _____. Therefore, it may not be tolerated in patients with ____ compromise.

Back 64

blood loss, cardiac

Front 65

How does trend influence CSF and ICP?

Back 65

increases

Front 66

Reverse trend can be good to expose the ____ for surgery.

Back 66

neck

Front 67

Cardiac effects of reverse trendelenberg

Back 67

decr CO, preload, and art pressure,
baroreflexes incr sympathetic tone, HR and PVR

Front 68

Respiratory effects of reverse trend

Back 68

decr WOB, incr FRC

Front 69

Many of the disadvantages of the trend position can be offset or eliminated by

Back 69

placing pt in reverse trend

Front 70

You shouldnt put a pt in reverse trend unless surgery warrants it, such as

Back 70

laparoscopic procedures

Front 71

What position is this?
flexion of spine to separate iliac crest and rib cage, upper leg straight, lower leg flexed, lower table flexed, padding at iliac crest, may minimize volume deficit

Back 71

kidney position

Front 72

Lateral decub is helpful in ____ procedures

Back 72

thoracic, renal, ortho

Front 73

In lateral decub, the head can be supported by _____ and the armboard is _____.

Back 73

mayo stand or bean bag support,
suspended

Front 74

Whats funny about an axillary roll?

Back 74

it aint in the axilla!
gets placed under rips just caudal to axilla

Front 75

In lateral decub, the _____ determines the name of the position.

Back 75

side down

Front 76

In lateral decub, the head must be aligned to support the spinal column and prevent

Back 76

compression of the dependent arm

Front 77

The ____ leg is flexed to provide stability and facilitate venous drainage in the lateral decub position.

Back 77

bottom leg

Front 78

In lateral decub, the ____ nerve is susceptible to injury.

Back 78

peroneal

Front 79

What are the anesthetic challenges of the lateral decub position?

Back 79

- compression of vena cava w kidney rest
- dependent lung underventilated
- nondependent lung overventilated d/t incr compliance
- blood flows to undervent lung by gravity
- VQ mismatch -- hypoxemia

Front 80

The kidney rest should be placed under

Back 80

the bony iliac crest - not fleshy waist area

Front 81

Axillary rolls should be placed under

Back 81

scapula to relieve pressure on arm and foster adequate chest excursion

Front 82

Misplacement of axillary roll could cause

Back 82

compression of brachial plexus from humerus

Front 83

In lateral decubitus position _______ must be padded.

Back 83

dependent shoulder, axilla, deltoid

Front 84

In lateral decub, the lower arm is placed ____ to prevent pressure on brachial plexus

Back 84

forward

Front 85

In lateral decub during chest surgery, the upper arm should be

Back 85

flexed at elbow and raised above head to elevate scapula and widen intercostal spaces

Front 86

Cardiac effects of lateral decub

Back 86

output unchanged unless venous return obstructed w kidney rest -- might have decr art BP due to decr vasc resistance

Front 87

Respiratory effects of lateral decub

Back 87

decr volume and incr perfusion of dependent lung -- vq mismatch!

Front 88

The lung up _____ better but the lung down _____ better.

Back 88

ventillates, perfuses

Front 89

Disadvantages of lateral decub

Back 89

- decr FRC in dependent lung
- incr risk of atelectasis in dependent lung
- gravity causes incr perfusion of dependent lung -- vq mismatch!

Front 90

Disadvantages of kidney rest

Back 90

patient instability, impairment of venous return from legs causes decr CO and BP, restricted chest wall mvmt on dependent side, incr facial swelling and ICP, vq mismatch

Front 91

In the sitting position, _____ force is pushed downward.

Back 91

visceral

Front 92

The other name for the lawn chair position is _____. Describe:

Back 92

dorsal recumbent,
table flexed under lumbar area, pad under head, distal flexion under knees, leg strap above knees, arms abducted < 90 or tucked

Front 93

Cardiac consequences of sitting position

Back 93

- pooling blood in lower body decr central blood volume
- incr venous return and decr risk of DVT w SCDs
- ABP decr despite incr in HR and SVR (30%)
- CO decr 20-40%
- intrathoracic blood volume decr 500 mL

Front 94

Resp consequences of sitting position

Back 94

- lung vol incr
- FRC incr
-WOB decr

Front 95

Sitting position is used for what types of cases?

Back 95

posterior fossa craniotomies, shoulder and breast procedures

Front 96

In crani cases, The sitting position facilitates ____ from the head, and improves surgical exposure and decr _____ pressure.

Back 96

venous drainage, cerebral perfusion

Front 97

The sitting position may cause _____ hypotension

Back 97

postural

Front 98

This is a risk from being in the sitting position, where negative pressure gradient exists between right atrium and veins at operative site.

Back 98

venous air emboli

Front 99

complications of venous air emboli

Back 99

may be no effect to...
hypotensino, arrhythmias, cardiac arrest, death

Front 100

_____ is the gold standard for venous air embolism detection

Back 100

TEE

Front 101

What are the S/S of venous air embolism?

Back 101

incr dead space, drop in ETCO2, presence of ETnitrogen, mill wheel murmur, incr PAP and hypoxia

Front 102

How do you treat venous air embolism?

Back 102

entrained air emboli are removed by aspiration through a multiorifice central venous catheter

Front 103

Pneumocephalus, edema of face/head/neck due to prolonged neck flexion resulting in venous/lymphatic obstruction, and sciatic nerve injury are all possible complications of

Back 103

the sitting position

Front 104

Sciatic nerve injury is caused by bended knees without flexion of the ____. The clinical manifestation is ____.

Back 104

hips, foot drop

Front 105

Describe sitting/modified fowler

Back 105

pt positioned over break in table, footboard perpendicular, best rest up 45-75 degrees, knees flexed, arms on lap over pillow, shoulders supported w tape

Front 106

Lithotomy patients are in ____ position for induction, then moved down in bed and legs are moved _____ while foot of table is lowered.

Back 106

supine, simultaneously

Front 107

For lithotomy position, the hips and knees are ____ and thighs are ___ and externally rotated 90 degrees.

Back 107

flexed, abducted

Front 108

Lithotomy position is often used in conjunction w ____ position, for ____ cases.

Back 108

trendelenberg,
uro and gyn

Front 109

In lithotomy position, it is very important to pad

Back 109

between metal leg braces and pt legs

Front 110

In lithotomy position, both legs should be flexed at the same time to avoid

Back 110

stretching peripheral nerves

Front 111

In lithotomy, thighs should be no more than ___ Degrees flexed.

Back 111

90

Front 112

_____ may develop in the lithotomy position when perfusion pressure to an extremity is inadequate, resulting in ischemia.

Back 112

compartment syndrome

Front 113

Greater than ___ hours in lithotomy position could result in muscle ischemia and massive edema leading to tissue necrosis.

Back 113

4 hrs

Front 114

Lithotomy causes a _____ displacement of the diaphragm

Back 114

cephalad

Front 115

In lithotomy, the common peroneal nerve located on the lateral aspect of the knee may be damaged leading to

Back 115

foot drop

Front 116

A damaged femoral nerve causes decreased or absent

Back 116

knee jerk

Front 117

A damaged saphenous nerve results from

Back 117

compression against the medial tibial condyle

Front 118

A damaged obturator nerve leads to

Back 118

inability to adduct leg and diminished sensation over medial thigh

Front 119

A damaged sciatic nerve leads to

Back 119

lower extrem motor neuropathy and foot drop

Front 120

What are the advantages of the lithotomy position?

Back 120

access to head/airway, access to arms, incr circulating bloow volume and preload (autotransfusion from leg vessels depending on volume status)

Front 121

What are the disadvantages of the lithotomy position?

Back 121

- injury w excessive hip rotation, brachial plexus injury, > 4 hrs incr risk of neuropathy 45%
- decr VC and aspiration risk due to diaphragm cephalad
- lowering legs produces hypotension - venous stasis
- post op back ache

Front 122

In lithotomy position, the obturator nerve can be damaged if

Back 122

> 90 degree flexion of thigh stretches/compresses nerve at inguinal ligament

Front 123

In lithotomy position, the common peroneal nerve can be damaged if

Back 123

compressed against fibula by candy canes

Front 124

Nurse anesthetists should ___ and ____ patient positioning and protective measures at frequent intervals.

Back 124

monitor and assess

Front 125

3 most common nerve injuries

Back 125

1. ulnar 28%
2. brachial plexus 20%
3. common peroneal 13%

Front 126

Neurovascular injury is most likely to occur when a combination of

Back 126

nerve compression and stretching occurs for > 20 minutes

Front 127

In peripheral nerve injuries, ____% undergo complete recovery and ____ % are left w residual weakness/sensory loss

Back 127

90%, 10%

Front 128

General anesthesia removes many of the body's natural

Back 128

protective mechanisms

Front 129

Ulnar nerve injury is more common in ____ because there is less protective adipose tissue.

Back 129

men

Front 130

What are the 2 major sites of ulnar nerve damage at the elbow?

Back 130

1- condylar groove (post medial epicondyle of humerus)
2- cubital tunnel (cubital tunnel entrapment syndrome)

Front 131

Most common post op peripheral nerve injury

Back 131

ulnar

Front 132

How does blood pressure cuff affect ulnar nerve?

Back 132

repeated or sustained inflation may injure ulnar nerve

Front 133

Classic ulnar nerve injury presentation

Back 133

claw hand

inability to abduct/oppose 5th finger w diminished sensation in 4th and 5th fingers

Front 134

Ulnar nerve injury can be prevented by

Back 134

supinating arms

injury caused by pronation!

Front 135

____ increases risk of ulnar nerve injury.

Back 135

hypotension and hypoperfusion

Front 136

Brachial plexus injury develops from

Back 136

excessive arm abduction or external rotation

Front 137

Brachial plexus injury can be prevented by

Back 137

avoiding > 90 degree abduction (60 preferred); avoid arm falling off table; avoid opposite lateral head rotation;
when prone- maintain abduction no more than 90 degrees;
when lateral- place chest roll under lateral thorax

Front 138

A median sternotomy during open heart surgery may lead to what peripheral nerve injury

Back 138

brachial plexus

Front 139

Describe the nerve distribution between C4-T1

Back 139

Roots
Trunks
Divisions
Cords
Terminal Branches

"Reasons To Drink Cold Beer"

Front 140

This nerve injury is caused by direct pressure against the neck of the fibula on the nerve w legs in lithotomy position or in lateral decub

Back 140

peroneal nerve

Front 141

Peroneal nerve compression can be avoided with

Back 141

adequate padding of candy canes

Front 142

This nerve can be injured when the arm falls off the OR table or if pressure is applied to it as it traverses through the humerus spiral groove -- manifests w wrist drop, inability to extend metacarpophalangeal joints, and weakness of thumb abduction

Back 142

Radial nerve injury

Front 143

This nerve injury is unlikely from positioning, but rather IV drug injection, and manifests as ability to oppose digits 1 and 5

Back 143

median nerve

Front 144

This nerve is injured from compression of the nerve under the piriformis muscle or by stretching in lithotomy position. It is manifested w foot drop and lower extrem motor neuropathy

Back 144

sciatic nerve

Front 145

This is the most frequently damaged nerve in hte lower extrem, manifests w foot drop, loss of dorsal extension of toes, and inability to evert foot

Back 145

common peroneal nerve injury

Front 146

This nerve injury results from compression at pelvic brim or by excessive angulation of thigh when pt is in lithotomy. It results in decr or absent knee jerk and loss of flexion of hip and extension of knee

Back 146

femoral nerve injury

Front 147

This nerve is damaged by compression against medial tibial condyle, and can be avoided w preventing external compression against medial upper tibia

Back 147

saphenous nerve injury

Front 148

This nerve is damaged during difficult forceps delivery or excessive flexion of thigh to groin; it is manifested w inability to adduct leg and diminished sensation over medial thigh

Back 148

obturator nerve injury

Front 149

A simple post op assmt of extrem nerve function may lead to

Back 149

early recognition of peripheral neuropathies

Front 150

In order to maintain vigilance of pt positioning, provide info for continued improvement of processes, and ensure medicolegal defense, it is imperative to

Back 150

DOCUMENT!!

Front 151

Positioning checklist:

Back 151

1. scalp, head, face protected from tight mask straps
2. ears protected from traumatic pressure/objects
3. head, neck, c-spine supported in straight line
4. chest and torso kept in physiologic position for adequate full, bilat resp exchange and expansion
5.breasts and genitals protected from excessive pressure, trauma, rubbing
6. arms in physiological position and supported
7. back in physiologic position, spine in straight line, slight sacral curvature, cushions to relieve presure/stretching
8. thighs/legs in straight line of flexed position, no pressure on bony prominences or lateral knees/patellas
9. heels/toes/ankles free of pressure/rubbing
10. safety belt snug over pt w blanket or towel to prevent maceration
11. straps and positioning devices padded

Front 152

Orbital cavity and eye injuries (corneal abrasions/blindness) have major consequences and are

Back 152

AVOIDABLE

Front 153

Decreased FRC causes atelectasis and VQ problems compounded w

Back 153

extreme positions