Quiz 3 Basics Of Anesthesia

Front 1

WHAT DO YOU NEED TO MAKE SURE OF WHEN POSITIONING A PATIENT?

Back 1

you must have adequate access to the airway, medication, and iv access and be able to monitor the patient

Front 2

WHAT SHOULD YOU DO IF THE PATIENT IS MOVED?

Back 2

you must listen and document breath sounds, check bp

Front 3

WHAT IS THE BIGGEST PHYSIOLOGIC CONSEQUENCE OF POSITION CHANGES?

Back 3

Hypotension, b/c anesthesia blunts the compensatory SNS relexes that would normally minimize the changes associated with postion changes.

Front 4

PRE OP CONSIDERATIONS?

Back 4

extremes of any: age, body habitus, pre-existing neuro issues, DM, PVD, arthritis, smoking/alcohol, and pre-existing lesions/ injuries.

Front 5

TIDAL VOLUME

Back 5

amount of gas inspired, or expired with each normal breath

Front 6

INSPIRATORY RESERVE VOLUME

Back 6

maximum amount of additional air that can be inspired from the end of normal inspiration

Front 7

EXPIRATORY RESERVE VOLUME

Back 7

maximum volume of additional air that can be expired from the end of normal expiration

Front 8

RESIDUAL VOLUME

Back 8

volume of air remaining in the lung after maximal expiration.
***this is the only lung volume which cannot be measured with a spirometer

Front 9

LUNG CAPACITIES

Back 9

subdivisions of total volume that include two or more of the 4 basic lung volumes

Front 10

FRC

Back 10

functional residual capacity
amount of air remaining in lungs after quiet expiration

Front 11

FRC

Back 11

volume that we can replace with 100% O2

Front 12

TLC

Back 12

total lung capacity
volume of air in lungs at the end of maximal inspiration
Called a capacity b/c it is the sum of all 4 basic lung volumes (TLC = RV + IRV + TV + ERV)

Front 13

VITAL CAPACITY

Back 13

maximum volume of air that can be forcefully expelled from the lungs following a maximal inspiration (VC = IRV + TV + ERV) or (VC = TLC - RV)

Front 14

FRC

Back 14

volume of air remaining in the lung at the end of normal expiration. called a capacity because it equals residual volume plus expiratory reserve volume (FRC = RV + ERV)

Front 15

INSPIRATORY CAPACITY

Back 15

Maximum volume of air that can be inspired from end expiratory position (of less importance than the other capacities)
(IC = TV + IRV)

Front 16

SUPINE POSTION

Back 16

-FRC decreased by 20% (abdominal contents limit mvmt of diaphragm, decreased muscle tone from GA) - small airways close sooner --> hypoxia - VQ changes cause shunting --> hypoxia - gravity increases blood flow (perfusion) to lung zone III (dorsal) - decreased pulmonary compliance - minimal CV changes - obese people (compression of IVC supine hypotension syndrome) - pressure on occiput (alopecia * pad the head)

Front 17

SUPINE POSITION

Back 17

keep hips and knees slightly flexed, blanket pillow under knees, legs uncrossed, heels padded, correct anatomical spinal placement, arms (if on side must be padded and tucked) (if on arm boards * padded palms up supinated less than 90 degrees)

Front 18

ULNAR NERVE INJURY

Back 18

#1 in anesthesia related nerve injuries
*manifested by inability to abduct the 5th finger * weakness / atrophy of hand muscles "claw hand" *
prevented by supination, and avoid hypotension and hypoperfusion, pad arms properly
MOST SUPERFICIAL NERVE

Front 19

BRACHIAL PLEXUS INJURY

Back 19

excessive external rotation or abduction of the arm
*avoid > 90 degree abduction
* avoid arm falling off the table
* watch lateral head rotation
* if prone watch flexion and abduction of arms overhead
* lateral position requires an axillary roll which avoids the compression of humerus into the axilla
***manifestation of general weakness of the upper arm

Front 20

TRENDELENBURG

Back 20

*causes further pressure upwards on the diaphragm, from abdominal contents and further decreases lung expansion
* Increases ICP by decreasing venous drainage
* IOP increased with glaucoma
* increased risk of aspiration
head down feet up

Front 21

ACTIVATION OF BARORECEPTORS INCREASE IN BP ?

Back 21

increase in baroreceptor discharge
**inhibits SNS (vasoconstriction) and enhances vagal tone (bradycardia)

Front 22

MENDELSON SYNDROME?

Back 22

aspiration of > 25cc of gastric contents with a pH of < 2.5

Front 23

SHOULDER BRACES?

Back 23

can inhibit venous and carotid

Front 24

LITHOTOMY

Back 24

**can autotransfuse 500cc blood to core
can impair ventilation due to upward pressure
Most common nerve injury **common peroneal
but also- sciatic, femoral, saphenous, and obturator
**hypotension when the legs are put down
**must put legs up and down simultaneously this avoids stretching of one side of the nerve
> than 4 hours increases risk of injury ischemia, edema

Front 25

COMMON PERONEAL NERVE INJURY IN LITHOTOMY POSITION?

Back 25

occurs from compression of lateral aspect of fibula head (improper padding at stirrups)
Manifested by foot drop

Front 26

FEMORAL NERVE INJURY OF LITHOTOMY POSITION?

Back 26

excessive angulation of the thigh on the abdomen
MANIFESTED BY - decreased sensation on anterior thigh and inability to flex your hip

Front 27

FOPSS

Back 27

Femoral nerve - stressed by excessive angulation of the thigh
Obturator - stretched by excessive flexion of the thigh to the groin
Peroneal - compression of the lateral aspect of the legs at the head of the fibula against the stirrup supports
Saphenous - compression of the medial aspect of the legs against the stirrups
Sciatic nerve - stretched by excessive external rotation of the leg when placing the patient in the lithotomy position

Front 28

PRONE

Back 28

-need multiple people to help
- pt is log rolled
- place chest rolls from below clavicles to iliac crest (provide adequate lung expansion and help alleviate pressure on the abdomen)
**protect the genitalia and breasts
-pillows under lower legs and ankles to help flex knees and prevent pressure on the toes
-head positioned to side may impair drainage from the head
-cardiac - compression of abdominal viscera, pooling of blood in extremities, decreased preload, CO, BP, SV

Front 29

SYSTEMIC ISSUES WITH PRONE

Back 29

-cardiac - decreased preload, CO, BP, SV, and increased SVR and PVR
-pulm - decreased total lung compliance, increased work of breathing, ET placement
-OTHER- check and document face and eyes are free of pressure Q 15 min
**can cause ION Ischemic optic neuropathy (blindness), corneal abrasions

Front 30

REVERSE TRENDELENBURG

Back 30

decrease in CO, preload, and ABP
increased FRC, decreased work of breathing

Front 31

BARORECEPTOR RESPONSE IN REVERSE TRENDELENBURG

Back 31

b/c of the decrease in CO, preload, and bp--> baroreceptors sense the decreae in bp and increase SNS tone HR AND SVR

Front 32

LATERAL DECUBITUS

Back 32

keep bottom leg flexed
axillary roll placed just below axilla to avoid compression of the neurovascular bundle
**make sure you check the pulse in the dependent arm (put the pulse ox here)

Front 33

PHYSIOLOGIC CHANGES ASSOCIATED WITH THE LATERAL DECUBITUS

Back 33

Perfusion is gravity dependent, mechanical ventilation favors the nondependent lung, V/Q mismatch = decreased PaO2
***most important check for hypotension

Front 34

V/Q MISMATCHING

Back 34

ventilation without perfusion or the other way around
-ratio normal is 0.8
- normal ventilation is 4L and normal perfusion is 5L and 4/5 is 0.8

Front 35

V/Q MISMATCHING UNDER ANESTHESIA IN THE LATERAL POSITION

Back 35

ventilation decreases in dependent lung due to decreased compliance (compression by weight from abdominal contents)
*perfusion increases in the dependent lung due to gravity
clinical sig V/Q mismatching develops

Front 36

V/Q MISMATCHING CAUSES

Back 36

can be from 0 to infinity
**infinity (no perfusion) alveolar dead space
** 0 no ventilation intrapulmonary shunt (R-->L)
-dependent lung underventilated and more perfused
-nondependent lung - overventilated and less perfusion
increases in this mismatching will cause hypoxia

Front 37

SITTING POSITION

Back 37

used most often for posterior fossa, cervical spine, shoulder or neck surgery
-causes pooling of blood in the lower extremities ***decreased venous return by about 20%
*increased lung volumes and decreased work of breathing
beach chair more common than sitting way upright

Front 38

SYSTEMIC ISSUES WITH THE SITTING POSITION

Back 38

CARDIAC - VAE (venous air embolism) caused by open venous system above the level of the heart **atm pressure is greater than venous pressure and air is then sucked in
**If air is greater than pulm clearance, increase pulm pressures, decreased CO r/t increased right ventricular afterload

Front 39

S/S OF VENOUS AIR EMBOLISM

Back 39

listen to heart sounds at R second intercostal space by doppler or steth and listen for a milwheel murmur
** sudden decrease in ETCO2, decreased sats, arrythmias, and decrease in bp
Millwheel murmur is usually the first sign

Front 40

VAE TX

Back 40

-notify surgeon, flood field with saline or bone wax,
- aspirate air through CVP
- turn off nitrous 100% O2
- give volume to increase CVP
- vasopressors
- ?peep?
- turn on their left side to try to keep the air in the right atrium
increase the CVP so they suck in less air
-

Front 41

CONTINUED COMPLICATIONS OF THE SITTING POSITIONS

Back 41

hypotension, pneumocephalus, paraplegia/quadraplegia, ocular compression, edema of the face, tongue, and neck
- sciatic nerve damage

Front 42

WHAT FACE MASKS CAN DO

Back 42

can cause pressure damage over the nose, facial nerve damage from fingers, face straps can cause injury or even necrosis to face, ears, and eyes

Front 43

RISKS RELATED TO NERVE INJURY

Back 43

-nutritional status
- body habitus outside of normal
- history of previous nerve injury
- relative significance of the nerve injury
- Res Ipsa Locuitor makes defense challenging (it speaks for itself)

Front 44

MOST IMPORTANT THING DURING POSITIONING

Back 44

maintain control of the patients airway, IV access, and monitoring

Front 45

BRACHIAL PLEXUS NERVE

Back 45

HOW INJURED: * excessive abduction (> 90degrees) of arm * in prone positon when arm is used as a lever during turning * In supine/trendelenburg when shoulder braces are placed medially against the root of the neck
HOW MANIFESTED: weak arm function

Front 46

RADIAL NERVE INJURY

Back 46

HOW INJURED: compression against underlying humerus when lateral upper arm is compressed on the OR table
MANIFESTED BY: *inability to extend the wrist * Inability to abduct the thumb * wrist drop * decreased sensation over the dorsal surface of the lateral three and one half fingers

Front 47

ULNAR NERVE INJURY

Back 47

HOW INJURED: compression between medial epicondyle of the humerus and the sharp edge of the bed or frame
MANIFESTED: Sensory loss in fifth digit * claw hand

Front 48

MEDIAN NERVE INJURY

Back 48

HOW INJURED: indiscriminate probing (fishing) in the antecubital fossa during venipuncture
MANIFESTED: loss of sensation in finger tips from thumb to mid point of ring finger * Inability to oppose the first and fifth digits * decreased sensation on palmar surface of the lateral three and one half fingers

Front 49

MUSCULOCUTANEOUS

Back 49

HOW INJURED: compression nerve injury which is rare b/c of depth of nerve
MANIFESTED; inability to flex forearm

Front 50

INTERCOSTOBRACHIAL

Back 50

HOW INJURED: surgery in the axillary region
MANIFESTED: numbness or dysthesia of the upper inner arm

Front 51

MEDIAL CUTANEOUS

Back 51

HOW INJURED: compression at the cubital fossa
MANIFESTED: loss of sensation over the medial arm

Front 52

SCIATIC

Back 52

HOW INJURED: in sitting position compression of the on the ischial tuberosities * in lithotomy position thigh and nerves are externally rotated and knees are extended * excessive hip flexion resulting in nerve stretch * intramuscular injections
MANIFESTED: weakness of all skeletal muscles below the knee and diminished sensation over lateral half of the leg and almost all of the foot * foot drop * pain or numbness of lower leg, thigh, or foot

Front 53

FEMORAL NERVE INJURY

Back 53

HOW INJURED: in lithotomy extreme abduction of the thighs with external rotation of the hip * compression at pelvic brim by retractor or excessive angulation of the thigh
MANIFESTED: decreased or absent knee jerk, and loss of flexion of hip and extension of the knee * decreased sensation over superior aspect of the thigh and medial and anteromedial side of the leg

Front 54

SAPHENOUS NERVE INJURY

Back 54

HOW INJURED: Lithotomy position damage occurs when medial aspect of lower leg is suspended outside an unpadded support
MANIFESTED: parasthesis along the medial and anteromedial side of the calf

Front 55

COMMON PERONEAL NERVE INJURY

Back 55

HOW INJURED: lithotomy position pressure of vertical support pole for the leg or inadequate padding of metal knee supports which impact the popliteal fossa * in supine prolonged pressure in popliteal fossa by pillows or leg
MANIFESTED: foot drop * loss of dorsal extension of toes * inability to evert the foot

Front 56

OBTURATOR NERVE INJURY

Back 56

HOW INJURED: damaged during difficult forceps delivery or by excessive flexion of the thigh to the groin
MANIFESTED: inability to adduct the leg * diminished sensation over the medial side of the thigh

Front 57

ANTERIOR TIBIAL NERVE INJURY

Back 57

HOW INJURED: plantar flexion of the feet for extended periods of time
MANIFESTED: foot drop

Front 58

LATERAL FEMORAL CUTANEOUS NERVE INJURY

Back 58

HOW INJURED: nerve entrapment at inguinal ligament due to expanding abdominal girth
MANIFESTED: pain and dysthesia over lateral thigh