Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
45 Cards in this Set
- Front
- Back
|
When a person moves from the standing to the supine position does venous return to the heart initially increase or decrease?
|
Initially increases as pooled blood from the lower extremities redistributes toward the heart.
|
|
|
The most common surgical position producing the least hemodynamic and ventilatory changes:
a) prone b) lithotomy c) supine d) trendelenburg |
C) supine
|
|
|
Which of the following is NOT a complication of the supine position?
a) pressure alopecia b) backache c) headache d) pressure ischemia on bony prominences |
c) headache
|
|
|
Describe how pressure alopecia occurs.
|
prolonged immobilization of the head with its full weight falling on a limited area rendering the hair follicles ischemic.
|
|
|
Normal curvature of the lumbar back is:
a) kyphotic b) scoliotic c) lordotic d) none of the above |
c) lordotic
Backache may occur during surgery d/t losing tone during general anesthesia with muscle relaxation and/or neuraxial block and the normal lumbar lordotic curvature is lost in conjunction iwth loss of tone of the paraspinal musculature. |
|
|
Which peripheral nerve injury of the upper extremities is most common?
|
Ulner nerve injury
|
|
|
How does one position the upper extremities while in the supine position?
|
Abducted to the side <90 degree angle with hand and forearm either supinated or kept in a neutral position to reduce external pressure from the supporting surface (padded armboard) on the spiral groove of the humerus and the ulnar nerve.
Adducted (tucked) along side the body |
|
|
Trendelenburg position is:
a)supine patient bed tilted head up b)supine patient bed tilted head down c) supine patient bed not tilted and remains head neutral |
b)supine patient bed tilted head down
|
|
|
Which is a benefit of trendelenburg position?
a) decrease venous return b) improve exposure during thoracic surgery c) prevent emboli during central venous line placement |
c) prevent emboli during central line placement.
Other benefits are to improve exposure during lower abdominal surgery and to increase venous return during hypotension. |
|
|
What is the possible injury when using shoulder braces during trendelenburg position?
|
compressive injury to the brachial plexus.
|
|
|
Trendelenburg position does all of the following EXCEPT:
a) increases central venous pressure b) swelling of the face, conjunctiva, larynx, and tongue (increasing potential for upper airway obstruction) c) increases intracranial pressure d) no change to intraocular pressure |
d) no change to intraocular pressure.
Trendelenburg position actually increases IOP |
|
|
What position is frequently used during gynecologic and urologic surgery?
|
Lithotomy
|
|
|
In the lithotomy position the hips are flexed ___-____ degrees from the trunk and the legs are abducted ___-____ degrees from the midline.
|
hips flexed 80-100 degrees from the trunk
legs abducted 30-45 degrees from the midline. |
|
|
In lithotomy position the legs are raised and lowered together (flexing both hips and kenes simultaneously) to prevent what complication?
|
torsion of the lumbar spine
|
|
|
What nerve injury is most common during the lithotomy position and how does it occur?
|
Injury to common perineal nerve
compression of the nerve between the lateral head of the fibula and the bar holding the legs |
|
|
What physiologic complication is associated with the lateral decubitus position?
|
pulmonary compromise
|
|
|
Where is the axillary roll (aka chest roll) placed and why is it placed during the lateral decubitus positioning?
|
placed just caudad to the dependent axilla while the dependent arm is placed perpendicular to the torso on a padded armboard.
Placed to avoid compression injuries to the brachial plexus and allow diaphragmatic excursion so the weight of the thorax is borne by the chest wall caudad to the axilla rather than by the axilla itself. |
|
|
When in the lateral position how does one position the dependent leg?
a) flexed b) straight c) parallel with the upper leg d) hyperextended |
a) flexed
minimizes excessive pressure on bony prominences and stretch of the lower extremity nerves |
|
|
During the sitting position patients are prone to what hemodynamic changes?
a) hypertension b) cardiac arrythmias c) hypotension |
c) hypotension
pooling of the blood i the lower part of the body |
|
|
Excessive flexion of the neck can:
a)increase drainage of blood from the brain b) impede both arterial and venous blood flow c) hyperperfusion d) relieve pressure on the tongue |
b) excessive flexion can impede both arterial and venous blood flow and cause hypoperfusion and inadequate drainage of the brain, obstruct (kink) the ETT andplace significant pressure on the tongue leading to macroglossia.
|
|
|
How many fingerbreadths distance is required between the chin and the sternum for a safe degree of neck flexion in the sitting position?
|
at least two fingerbreadths
|
|
|
ulnar nerve neuropathy manifests as all of the following except:
a) claw-like hand b) inability to abduct/oppose the 5th finger c) diminished sensation in the 4th and 5th fingers d) inability to extend the forearm |
d) inability to extend the forearm (this is a function of the radial nerve not the ulnar nerve)
|
|
|
Where is it thought that ulnar nerve damage occurs (pathology)?
|
ulnar nerve is superficial at the elbow
Hyperflexion of the elbow and compresson of the nerve at the condylar groove and the cubital tunnel against the posterior aspect of the medial epicondyle of the humerus. |
|
|
Where is it thought that radial nerve damage occurs (pathology)?
|
Direct pressure as it traverses the spiral groove of the humerus in the lower third of the arm.
Manifested as wrist drop with inability to abduct the thumb or extend the metacarpophalangeal joints. |
|
|
Where is it thought that median nerve damage occurs (pathology)?
|
Insertion of IV into antecubital fossa at the point where the nerve is adjacent to the medial cubital and basilic veins.
Unable to oppose the 1st and 5th fingers, decreased sensation over palmar surface of the lateral 3.5 fingers |
|
|
Which nerve can be stretched with external rotation of the leg?
|
Sciatic nerve
Because it is fixated between the sciatic notch and the neck of the fibula |
|
|
Which nerve has been damaged when the patient complains of foot drop, inability to extend the toes in a dorsal direction or evert the foot?
|
The common peroneal nerve (which is a branch of the sciatic nerve)
|
|
|
Which nerve was injured when the patient in not able to adduct the leg and has decreased sensation over the medial side of the thigh?
|
Obturator nerve
|
|
|
When the patient has decreased flexion of the hip, decreased extension of the knee, loss of sensation over the superior aspect of the thigh and medial/anterolateral side of the leg which nerve injury most likely occurred?
|
Femoral nerve
|
|
|
What is the most common type of perioperative eye injury?
|
corneal abrasion
|
|
|
What are the perioperative risk factors for ION (ischemic optic neuropathy)?
|
prolonged hypotension
long duration of surgery prone position excessive blood loss excessive crystalloid use anemia or hemodilution increased intraocular or venous pressure from prone position |
|
|
What are patient risk factors for ION (ischemic optic neuropathy)?
|
systemic HTN
DM atherosclerosis morbid obesity tobacco use |
|
|
A patient with which of the following eye diseases would be at greatest risk for retinal damage from hypotension during surgery?
a) strabismus b) cataract c) glaucoma d) severe myopia e) open eye injury |
c) glaucoma
blood flow to the retina can be decreased by either a dec. in MAP or an increase in IOP. Decreased blood flow and stasis are more likely in patients with glaucoma d/t the latter have high IOP. During periods of prolonged hypotension, the incidence of retinal artery thrombosis increases in these patients. |
|
|
Damage to which nerve may lead to wrist drop?
a) Radial b) Axillary c) Median d) Ulnar |
a) radial
Weakness in abduction of the thumb inability to extend the metacarpophalangeal joints wrist drop numbness in the webbed space b/w the thumb and index fingers Radial nerve passes around the humerus b/w the middle and lower portions of the spinal groove posteriorly. As it wraps around the bone, the radial nerve can become compressed between it and the OR table, resulting in nerve injury. |
|
|
After an 8 hour ex-lap the patient is unable to oppose the left thumb and left little finger. Damage to which nerve accounts for this?
a) radial b) ulnar c) musculocutaneous d) median |
d) median nerve
median nerve provides sensory to palmar surface of the lateral 3.5 fingers and adjacent palm Motor--abductor pollicis brevis, flexor pollicis brevis, and opponens pollicis muscles. |
|
|
Weakness of all muscles below the knee related to which nerve injury?
a) sciatic nerve b) common peroneal nerve c) femoral nerve d) obturator nerve |
a) sciatic nerve
|
|
|
Which nerve was damaged indicative of foot drop; loss of dorsal extension of the toes?
a) sciatic nerve b) common peroneal nerve c) femoral nerve d) obturator nerve |
b) common peroneal nerve
|
|
|
Which nerve was damaged indicative of weakness of the muscles that extend the knee?
a) sciatic nerve b) common peroneal nerve c) femoral nerve d) obturator nerve |
c) femoral nerve
|
|
|
Which nerve was damaged indicative of inability to adduct the leg; diminished sensation over the medial side of the thigh?
a) sciatic nerve b) common peroneal nerve c) femoral nerve d) obturator nerve |
d) obturator nerve
|
|
|
Which nerve is most commonly damaged caused by placement of patient into the lithotomy position?
a) sciatic nerve b) common peroneal nerve c) femoral nerve d) obturator nerve |
b) common peroneal nerve injury
close second is the sciatic nerve injury...remember that the common peroneal nerve is a branch off of the sciatic nerve |
|
|
Which nerve was damaged indicative of numbness over the medial/anterior medial portion of the leg and the superior aspect of the thigh?
a) sciatic nerve b) common peroneal nerve c) femoral nerve d) obturator nerve |
c) femoral nerve
|
|
|
The most frequently damaged nerve in the lower extremity in anesthetized patients is the
a) obturator b) femoral c) saphenous d) common peroneal |
d) common peroneal nerve
|
|
|
Each of the following is a relative contraindication to the sitting position EXCEPT:
a) ventriculoatrial shunt b) patent foramen ovale c) platypenea-orthodeoxia d) ventriculoperitoneal shunt |
d) ventriculoperitoneal shunt (air can not become entrained via the VP shunt directly into the circulation so it's not a relative contraindication)
platypenea-orthodeoxia is present when patients who are well oxygenated in the supine position but become hypoxic when they assume the upright position; these patients have a hemodynamic dependent right to left intracardiac shunt and tend to develop cerebral ischemia when the patient assumes the upright position. |
|
|
A patient in the sitting position suddenly develops hypotension. Air is heard onthe precordial Doppler ultrasound. Each of the following maneuvers to treat VAE are appropriate EXCEPT:
a) discontinue N2O b) implement positive end-expiratory pressure (PEEP) c) apply jugular venous pressure d) flood surgical wound with saline e) administer epinephrine to treat hypotension |
b) implement PEEP
Initiation of PEEP may increase the risk of paradoxical embolism or decrease venous effluent from the calvarium, resulting in increased CBV and ICP |
|
|
What is the approach to treating venous air embolism?
|
1) stop further air entrapment (notify surgeon: flood surgical field with saline)
2) aspirate entrained air 3) prevent expansion of existing air 4) support CV function 5) compress neck veins to increase jugular venous pressur mitigating/prevents further air entry helps to localize source of air |
