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;
151 Cards in this Set
- Front
- Back
|
What plane divides the body into left and right halves
|
Midsaggital, saggital, or medial
|
|
|
What plane divides the body into front/back or anterior/posterior
|
Coronal or frontal
|
|
|
What plane divides the body into upper/lower or cranial/caudal
|
Transverse
|
|
|
What is the most common eye injury during surgery
|
Corneal abrasions
|
|
|
What are the 5 forces which cause position related injuries
|
Pressure, obstruction, compression, stretching, and shearing
|
|
|
What are some sources of pressure
|
Pt's body weight against a surface, equipment resting on body, edge of a positioning fram or bed, positioning devices or leg holders, and surgeon leaning on pt
|
|
|
What are some examples of obstruction
|
Flexing of an extremity to such a degree that it occludes vessels, tourniquets, and retractors causing obstructed flow
|
|
|
What is shearing
|
Tissue damage caused as the patient is pulled across surfaces or when sliding the pt without using drawsheets
|
|
|
What areas are at greater risk for injury due to pressure
|
Skin and soft tissues overlying bony prominences
|
|
|
What is a typical capillary perfusion pressure and why is this significant
|
32 mmHg, any pressure over this disrupts bloodflow and can lead to ischemia
|
|
|
What tissues are position related injuries most common
|
Nerves, vessels, tissue/skin, and the skeletal system
|
|
|
What accounts for most injuries to nerves
|
Pressure, obstruction, and stretching
|
|
|
What types of nerves are most prone to injury
|
Nerves with long anatomical courses and those that occupy superficial positions in the body
|
|
|
What accounts for most vessel injuries
|
Pressure and obstruction
|
|
|
What accounts for most tissue/skin injuries
|
Pressure and shearing
|
|
|
What is a common skeletal injury related to positioning
|
Post-op backache
|
|
|
What causes post-op backache
|
Relaxation of the paraspinal muscles leading to flattening of the normal lumbar convexity with resulting tension in the interlumbar and lumbrosaccral ligaments
|
|
|
What can prevent post-op backache
|
Pillows under the knees
|
|
|
What is a vulnerable patient
|
Those whose protective mechanisms are not functioning at peak levels.
|
|
|
What makes a patient vulnerable
|
Anything that decreases blood flow, hypovolemia, anything that alters oxygenation, cancer, neurologic disorders, diabetes, bone fractures, edema, advanced age, and hypothermia
|
|
|
What are 3 vulnerable situations
|
Long surgical procedures, excessive constant pressure to particular areas of the body, and vascular surgery
|
|
|
Why must we prevent shivering
|
Shivering increases tissue O2 requirements 200-500% making a pt more vulnerable to injury
|
|
|
Procedures lasting more than 2 hrs increase the risk of tissue damage by how much
|
35-50%
|
|
|
Procedures lasting more than 3 hrs increase the risk of tissue damage by how much
|
Triple
|
|
|
What are some things that can cause excessive constant pressure to an area of the body
|
ETT tape over lip, ECG leads on back, NG resting on nare, IFV tubing and connections between pt and bed
|
|
|
What perioperative positions put the eyes at risk
|
All of them
|
|
|
What should be done to the eyes to protect them from chem or physical injury
|
Tape them shut, use goggles, and avoid pressure on the globe of the eye
|
|
|
What are sources of eye pressure
|
Poorly fitted mask and prone or lateral positions
|
|
|
What special considerations should be taken for the ears
|
Make sure the pinna and helix are not folded or pinched
|
|
|
What types of surgeries should goggles be utilized in
|
Thyroidectomy, ear surgeries, and spinal fusions
|
|
|
Where are the peripheral baroreceptors located
|
Bifurcation of the common carotid, and in the aortic arch
|
|
|
What is the bainbridge reflex
|
As CVP goes up and more blood enters the heart stretch recpetors in the RA send signals to inhibit the PNS and increase heart rate
|
|
|
What effect do sympatholytics have on baroreceptors
|
They depress their normal function, thus small changes in position can drop blood pressure drastically
|
|
|
The depressant effects of sympatholytics are what, and what can be done to prevent resulting drops in BP
|
Dose dependent, Have anesthesia light while repositioning. Reposition incrementally over a period of 15 minutes
|
|
|
What are the 4 effects of posture on respiration
|
Changes of pulmonary blood flow, changes in lung compliance, changes in intrapulmonary dist of inspired air, and mechanical interference
|
|
|
In an awake pt what is the primary force of inspiration
|
The downward movement of the diaphragm accounting for 75% of the change in chest volume
|
|
|
What happens to lung volumes in the awake pt when they are placed supine
|
The diaphragm contributes only 60 of the ventilatory force due to abdominal contents shifting up and stretching the diaphragm up
|
|
|
What are the changes that occur in the diaphragm in the anesthetized, mechanically ventilated pt
|
The diaphragm shifts more cephalad and reduction in lung volumes occur. Loss of EE tone lets abdominal contents shift further up. PPV does not return diaphragm to original position
|
|
|
What is a normal vital capacity
|
60-70 mL/Kg
|
|
|
What position yields the greatest VC and what yields the worst
|
Reverse trendelenberg is best, Lithotomy is the worst
|
|
|
What are the good and bad of the reverse trendelenburg position
|
It lowers intragastric pressure, lowering risk for regurgitation, but if there is regurg the contents stay in the oropharynx increasing the risk of aspiration
|
|
|
What are the good and bad of the trendelenberg position
|
Exact opposite of reverse trend
|
|
|
What position is the most used, but has the greatest number of complications
|
Supine
|
|
|
What is a cocern regarding maxillofacial surgery
|
Flexion of the head can cause the ETT to migrate to the right mainstem, extension can extubate the pt
|
|
|
Where should the safety strap be placed on a supine pt
|
Over the midthigh on top of a smooth sheet, not on the pt's skin
|
|
|
How tight should the safety strap be
|
Tight enough so you can get one hand underneath
|
|
|
What areas are the most vulnerable to pressure between the bones and the surface of the bed
|
Heels, elbows, and saccrum
|
|
|
What nerve roots is the brachial plexus derived from
|
C5-T1
|
|
|
What does the brachial plexus supply
|
Motor innervation and almost all sensory function to the upper limb
|
|
|
Why is the brachial plexus prone to injury
|
It comes in close proximity to a number of bony and relatively immobile soft tissue structures as it travels down the neck.
|
|
|
What forces lead to brachial plexus injury
|
Stretch and direct nerve compression
|
|
|
How should the pt be positioned (while in the supine position) to prevent brachial plexus injury
|
One or both arms on padded armboards at less than 90 deg angle to the torso, supinated, and gently secured
|
|
|
Stretching of the brachial plexus across the humeral-clavicular joint may occur when
|
Hyperabduction of the arm, the hand is forcibly pronated, the arm is extended and the head is rotated in the opposite direction, or shoulder rests are placed in the root of the neck
|
|
|
How can shoulder braces cause injury
|
By compressing the plexus against the numerous bony structures in the shoulder
|
|
|
If shoulder braces must still be used where should they be placed
|
So they lie over the acromium
|
|
|
What is an example of a brachial plexus injury not as a result of positioning and what can be done to prevent liability
|
It can happen as a resutl of a median sternotomy. Documentation of proper arm positioning
|
|
|
What vertebrae give rise to the ulnar nerve
|
C8 and T1
|
|
|
Describe the ulnar nerve anatomy
|
It travels medial to the axillary artery down through the muscles of the upper arm to the condylar groove, passes posteriorly under the medial epicondyle down to the ulnar side of the hand
|
|
|
How should the supine pt be positioned to prevent ulnar nerve injury
|
Arms on padded armboards, less than 90 deg, palms up, arm may be tucked at side with sheets, but must fit on mattress.
|
|
|
Where should the sheet used for positioning the arms at the sides be
|
Under the pt not the mattress, extending above the elbow to the midupper arm for support
|
|
|
If the pt is mummied how must the elbows be positioned
|
Flexed less than 90 deg and always padded
|
|
|
Where and why does ulnar nerve injury usually occur
|
Usually occurs at the elbow, because it is a long superficial unprotected nerve
|
|
|
What results from ulnar nerve injury
|
Claw hand
|
|
|
What causes ulnar nerve injury
|
Compression of the nerve aginst the medial epicondyle when: the hand is pronated, the elbow is unpadded, the elbow is allowed to hang over the bed, or the elbow is flexed more than 90 deg
|
|
|
Who is 5 times more likely to suffer an ulnar nerve injury
|
Males as compared to females
|
|
|
Other than males who may be more predisposed to ulnar nerve injury
|
Thin pts, pts with subclinical underlying neuropathies, pts with cubital tunnel syndrome, and postoperatvie injury such as long hospital stays
|
|
|
Where does the radial nerve originate from
|
C6, C7, and C8 roots of the brachial plexus
|
|
|
At what level does the radial nerve divide
|
At the level of the lateral epicondyle of the humerus
|
|
|
After division, what does each of the radial nerves do
|
The deep radial nerve is the motor nerve, the superficial radial nerve is the sensory nerve
|
|
|
Where does the superficial radial nerve pass to
|
The back of the hand
|
|
|
If using an ether screen how can it cause damage to the radial nerve
|
If the ether screen is tight up against the area just above the elbow
|
|
|
Other than an ether screen, what else can cause damage to the radial nerve
|
Surgeon leaning on the arm, tourniquet being used, and NIBP cycling frequently
|
|
|
What can result from radial nerve damage
|
Wrist drop
|
|
|
Where does the median nerve arise from
|
C6-T1
|
|
|
Where is the median nerve most superficial/vulnerable
|
As it passes through the antecubital space
|
|
|
What can cause median nerve damage
|
If the pt's arm is allowed to fall over edge of bed, indiscriminate poking of the IVs and extravasation
|
|
|
What results from damage to the median nerve
|
Sensory loss to the thumb, 1st, and 2nd fingers. Inability to pronate the forearm, weak wrist flexion, unapposed thumb (ape hand)
|
|
|
Overall, what nerves are at risk for injury if the arm is allowed to hang over the edge of the bed
|
Ulnar, radial, and median
|
|
|
What makes up the subclavian neurovascular bundle
|
The subclavian artery, subclavian vein, and the brachial plexus
|
|
|
What can cause injury to the subclavian vessels
|
Any malposition that would cause injury to the brachial plexus, hyperabduction of the arm
|
|
|
In positioning a pt prone what position should be avoided
|
The classic sleeping position, arms at side, flat on stomach and chest, head turned to side
|
|
|
What are indications for the prone position
|
Spinal procedures, posterior cranial surgery, ano-rectal surgery, ortho procedures (achilles repair), skin grafting
|
|
|
Regardless of positioning devices used what is the goal of positioning the prone pt
|
Relieving pressure from the abdomen. Thus preventing resistance to respiration, preventing compression of the vena cava, preventing compression of the lymph system
|
|
|
What is a concern of the prone pt undergoing spinal surgery
|
If the pt is lying on their abdomen, the intra-abdominal pressure increases leading to venous engorgement, which can cause rapid massive blood loss
|
|
|
Aside from the arms, what precautions must be taken in positioning the prone pt
|
Protect the breasts. Medial and cephalad is best. A roll is placed under the pelvis to protect male genitalia. A pad or pillow flexing the knees and providing plantar flexion of the feet as well as keeping pressure off the toes. Also, the head is padded keeping the neck in alignment with the spinal column and pressure off the eyes.
|
|
|
How should the arms be positioned on a pt in the prone position with the arms at the side
|
They must be elevated to remain in alignment with the body, palms should face toward the thighs, hands and wrists must bealigned in a functional position
|
|
|
How should the arms be positioned on a pt in the prone position with the arms on armboards
|
Armboards parallel to the table, padded, no muscles under tension, arms must not be brought over the head. The arms should be somewhat ventral to the transverse plane of the torso
|
|
|
What should be done after positioning a pt's arms
|
Check pulses and document
|
|
|
Where should the pieces of the Relton frame be positioned
|
Upper should be just below the shoulder or on both sides just below the acromium clavicular joint. Lowers should be in contact with the iliac crests
|
|
|
How many people are necessary to position a prone patient
|
At least 4
|
|
|
What is anesthesia's responsibility in repositioning the prone pt
|
The head and neck and keeping the airway
|
|
|
What should be done prior to postioning a pt prone
|
Intubation/induction, protect eyes, position equipment, 100% FiO2 on, detach monitors and disconnect circuit
|
|
|
What should be done immediately after positioning pt prone
|
Check everywhere for pressure and proper alignment, reconnect monitors, patent airway and IV, recheck breath sounds and document
|
|
|
What is one case where the patient is positioned prone prior to being put out
|
Unstable C-spine. Pt awake intubated and proned to monitor neuro function. Then out
|
|
|
What are the injuries that can result fro the prone position
|
Stretching of the brachial plexus, ulnar nerve injury, injury to the nerves and vessels of the dorsum of the foot, eye injuries due to pressure, and vessel injuries due to hyperabduction of the arms or compression of the brachial plexus
|
|
|
If arms are on armboards, how often shoudl the radial pulses be checked and documented as such
|
Q15 minutes
|
|
|
What are indications for the lateral position
|
Thoracic procedures, kidney procedures (rt lateral), ortho, and anterior spinal fusions
|
|
|
What are the proper ways to position a pt lateral
|
Intubate first, make sure head properly supported to align head and spine, torso supported to prevent movement (usually wide tape over torso and hips but not tightly), pillows placed between legs, bottom leg flexed, axillary role under upper chest, lower supinated on armboard less than 90 deg, and upper arm resting on top of pillows on top of lower arm
|
|
|
Why are pillows placed between the legs and the lower leg flexed of the lateral postioned pt
|
To eliminate the weight of the upper leg, facilitate venous drainage, and prevent rubbing or pressure to the lateral knee
|
|
|
Where does the axillary role go
|
Under the upper chest, NOT in the armpit
|
|
|
What are the areas of potential injury to the pt in the lateral position
|
Brachial plexus, the UE nerves, UE vessels, eyes, ears, LE nerves
|
|
|
How can the brachial plexus be injured in the lateral pt
|
The axillary role misplaced, the dependent arm positioned under the body, the upper arm is stretched above the head or hung on the ether screen, the arm is stretched to be positioned on a mayo stand
|
|
|
How may the ulnar nerve be injured in the lateral pt
|
The arm is improperly positioned on a mayo stand or the arm is allowed to hang over the edge of the bed
|
|
|
How may the radial and median nerves be injured in the lateral pt
|
The arm is improperly positioned on a mayo stand
|
|
|
How may the radial and brachial arteries be injured in the lateral pt
|
The arm is improperly positioned on a mayo stand
|
|
|
What is the largest nerve in the body
|
Sciatic
|
|
|
Where does the sciatic nerve arise from
|
L4, L5, S1, S2, and S3
|
|
|
What and where does the sciatic nerve split
|
It splits midway down the thigh to form the tibial nerve and the common peroneal nerve
|
|
|
Where is the peroneal nerve prone to injury
|
Where it winds around the fibular neck
|
|
|
What does the sural nerve arise from and how can it be injured
|
It arises from the tibial nerve and enters the foot behind the heel. It can be injured by lying lateral and the side of the heel is not padded
|
|
|
What are the indications for trendelenberg positioning
|
Surgical exposure for lower abdominal surgery, Increased short term venous return for low BPs and central line placement, and to minimize aspiration after regurg
|
|
|
What are areas of concern with the trendelenberg position
|
The use of shoulder braces could cause injury, PIP will increase due to pressure on diaphragm, and ICP and IOP will increase
|
|
|
Who should not be placed in trendelenberg position
|
Pts with CHF, CAD, high ICP, high IOP
|
|
|
What is the indication for reverse trendelenberg
|
Surgical exposure such as GIB
|
|
|
Describe the sitting position
|
Head supported by a skull pin holder, LE positioned at the level of the heart, hips flexed and knees are flexed, arms in the pt's lap or on pillows on the pt's lap to prevent stretching of the br. plexus
|
|
|
What are some areas of concern of the sitting position
|
Place a pad under knees and buttocks, don't let the arms rest on the edge of the table, blood pools in the extremities, thus TEDS should be used
|
|
|
What are the indications of the sitting position
|
Posterior fossa craniotomies, and posterior cervical spine procedures
|
|
|
What are the risks (other than those related to postioning) of the sitting position during surgery
|
VAE, Quadriplegia d/t excessive neck flexion or decreased spinal perfusion, postural hypotension
|
|
|
What position is taking the place of the sitting position
|
Prone
|
|
|
What can be done to prevent exaggerated drops in BP due to postural hypotension
|
Raise the head of the bead slowly
|
|
|
Why is the incidence of VAE highest among sitting cranis
|
Because there are low pressure veins and largge venous sinuses in the area of the suregery that can be cut
|
|
|
Other than the obvious, what problem can occur from a VAE and why is this of concern
|
It can become a paradoxical air embolism thorugh a patent foramen ovale. Up to 25% of the population have the defect and don't know it
|
|
|
What are used to detect a VAE
|
TEE and precordial US
|
|
|
Describe the lithotomy position
|
Pt's buttocks placed at edge of table, legs lifted at same time and placed in stirrups
|
|
|
What are some considerations of the lithotomy position
|
Blood pools in the lumbar area, legs should be raised and lowered at same time to prevent spine and joint injuries, compartment syndroma of the hand may occur if compressed between butt and OR table, and fingers can fall over foot of the bed and get crushed
|
|
|
What nerves are at risk for injury in the lithotomy position
|
Common peroneal, femoral, obtruator, saphenous
|
|
|
What nerve can be damaged if the legs are placed inside the rods of the lithotomy stirrups and the leg is allowed to rest against them
|
Peroneal
|
|
|
What are the 2 major nerve plexuses of the LE
|
Lumbar plexus and lumbrosaccral plexus
|
|
|
What makes up the lumbar plexus
|
The obtruator, femoral, and lateral femoral cutaneous nerve
|
|
|
What makes up the lumbrosacral plexus
|
The sciatic nerve and it's branches
|
|
|
Where does the femoral nerve originate
|
L2-L4
|
|
|
What does the femoral nerve supply
|
Motor function to the iliac muscles and mutliple muscles of the leg. Sensation to anterior and lower portion of the thigh
|
|
|
How can the femoral nerve be injured
|
Angulation of the thigh can stretch the inguinal ligament and compress the nerve
|
|
|
Where does the obtruator nerve arise from
|
L2-L4
|
|
|
What does the obtruator nerve supply
|
Motor to many thigh muscles and sensory to the medial portion of the thigh
|
|
|
How can the obtruator nerve be injured
|
Stretching of the nerve as it exits the obtruator foramen
|
|
|
What does the saphenous nerve supply
|
Sensory to the medial side of the leg and to the ankle and foot
|
|
|
How can the saphenous nerve be injured
|
When the legs are positioned outside of the lithotomy poles and the legs are allowed to rest against the pole. Pressure over the medial tibial condyle can result in injury
|
|
|
What is the indication of the exaggerated lithotomy position
|
Procedures that require transperineal access to the retropubic areas...perineal prostatectomy
|
|
|
What are some areas of concern for the exaggerated lithotomy position
|
Increased Iabd pressure limits diaphragm movement, high leg elevation stresses the lumbar spine, lumbrosaccral muscles, and ligaments, LE perfusion is reduced and long surgeries have a high incidence of LE compartment syndrome
|
|
|
What is the indication of the jack-knife position
|
Procedures that need exposure to the saccral, rectal, and peri areas
|
|
|
What are the areas of concern of the jack-knife position
|
The hips must be at the break in the table, expect hemodynamic changes due to dependant position of the head and LE, expect vent changes d/t pressure on diaphragm
|
|
|
What two apparatuses are use for the knee-chest position
|
Tarlov seat on an OR bed, or the Andrews frame
|
|
|
Why is the Tarlov seat not used much anymore
|
Risk for compression of the peroneal nerve and potential for crushing injuries to the toes when raising the foot of the bed
|
|
|
What are the indications for the Andrews frame
|
Lumbar laminectomies and discectomies
|
|
|
What's good about the andrews frame
|
Weight of the torso supported by knees and chest, obese pt's belly can hang free
|
|
|
What are areas of concern with the Andrews frame
|
Peroneal nerve in the lateral aspect of the knee needs padding, venous pooling in the legs and low BPs, Pt needs to be stabilized on table with wide tape or safety straps
|
|
|
What are the indications to the flexed lateral position
|
Thoracic procedures and procedures needing an approach to the kidney
|
|
|
Where should the iliac crest be when positioning a pt in the flexed lateral position
|
At the break in the table
|
|
|
Where should a kidney rest be placed
|
Between the 12th rib and the iliac crest, best if underneath the bony iliac crest
|
|
|
If the kidney rest is placed or the break in bed is elevated at a fleshy part of the body what can happen
|
Soft tissues and vessels can be compressed and impair circulation. The inferior vena cava is at risk of being compressed in the rt lateral position
|
