Mod10: Orthopedic surgery - Surgery on the Lower Extremities

Question 1

_{Surgery on the Lower Extremities - Surgery to the Hip and Femur}

Hip fractures

^{Patient population/Pre-op considerations:}

Answer 1

Elderly

^{Many patients are frail and elderly}

Morbidity and mortality

^{Mortality rate following hip fx up to 10% during initial hospitalization}

^{25% within one year following fx}

Co-morbidities

^{Many have a number of co-morbidities (CAD, cerebrovascular disease, COPD, DM, OSA)}

Dehydrated

^{Many are dehydrated from inadequate oral intake}

^{Hemoconcentration can lead to a deceptively normal Hct or Hgb preoperatively}

Question 2

_{Surgery to the Hip and Femur - Anesthetic techniques}

GA versus regional (SAB or epidural):

Answer 2

Should take into consideration the type of reduction and fixation to be used

This depends on fx site, degree of displacement, preoperative functional status of patient, surgeon preference

Question 3

_{Surgery to the Hip and Femur - Anesthetic techniques}

Regional (SAB or epidural) technique:

Answer 3

15 RCTs showed decreased in postop DVT and 1-month mortality with RA…but these benefits do not persist past 3 months

You can see less postoperative delirium and postop cognitive dysfunction with RA if you use minimal sedation with the regional technique

Question 4

_{Surgery to the Hip and Femur - Anesthetic techniques}

Spinal anesthesia

^{advantage/ best LA & their benefits:}

Answer 4

A spinal or epidural, with or without GA, has the advantage of enhanced postoperative pain control

If you use a spinal, hypobaric or isobaric local anesthetics are ideal for positioning, since the patient can lie on the nonoperative hip for the placement of the SAB and the surgery​

Question 5

_{Surgery to the Hip and Femur - Hip Arthroplasty}

Longer, more invasive procedures

^include:

Answer 5

Hemi-arthroplasties & Total Hip Arthroplasties (THA)

are long and more invasive procedures

usually done in lateral decubitus position.

Question 6

_{Surgery to the Hip and Femur - Hip Arthroplasty}

Blood loss:

Answer 6

Both hemiarthroplasties and total hip arthroplasties have greater blood loss

Can result in significant hemodynamic changes, especially if cement is used

Make sure you have large bore IV and type and cross preop

Question 7

_{Surgery to the Hip and Femur - Hip Arthroplasty}

OA, RA, avascular necrosis

^{important intubation conerns:}

Answer 7

Most patients having a THR has OA, RA, or avascular necrosis

Mentioned RA before – discussed their limited cervical range of motion

Atlantoaxial subluxation can be diagnosed with x-ray and during intubation

This can lead to protrusion of the odontoid process into the foramen magnum

=> this can impede vertebral blood flow and compress the spinal cord and brain

Flexion and extension lateral radiographs of the c-spine in patients with severe RA should be obtained before surgery

=> these would be patients who have RA that is severe enough to require methotrexate, steroids, or immune therapy

If atlantoaxial instability is present –> need to intubate with inline stabilization using a Glidescope, c-mac, or fiberoptic laryngoscopy

Question 8

_{Surgery to the Hip and Femur - Hip Arthroplasty}

THA consists of several steps:

Answer 8

Femoral head is dislocated and removed

There is reaming of the femur and insertion of a femoral component into the femoral shaft

Question 9

_{Surgery to the Hip and Femur - Total Hip Arthroplasty (THA)}

Positioning

Answer 9

Lateral decubitus or supine

Question 10

_{Surgery to the Hip and Femur - Total Hip Arthroplasty (THA)}

Potential for complications:

Answer 10

Bone cement implantation syndrome

Hemorrhage

Venous thromboembolism

Question 11

_{Surgery to the Hip and Femur - Total Hip Arthroplasty (THA)}

Types of specific procedures:

Answer 11

Hip surfacing arthroplasty

Bilateral arthroplasty

Revision arthroplasty

Minimally invasive arthroplasty

Hip arthroscopy

Question 12

_{Surgery to the Hip and Femur - Total Hip Arthroplasty (THA) - Types}

Bilateral arthroplasty

^{how does procedure on 1st hip influence second procedure?}

Answer 12

Second procedure can be done safely as long as there is no occurrence of significant PE after the first femoral component is inserted

Be sure to be in good communication with the surgeon

If there are significant hemodynamic changes or instability during first hip, then the second hip should be postponed

Question 13

_{Surgery to the Hip and Femur - Total Hip Arthroplasty (THA) - Types}

Revision arthroplasty

^{blood loss compared to original procedure:}

Answer 13

Can have much larger blood loss than original surgery

Can also take longer than routine arthroplasty

Depends on a number of factors, including surgeon skill

Consider preop autologous donation; and intraop salvage techniques

Some studies indicate decreased blood loss during hip surgery if regional rather than general technique used

Exact mechanism is not clear

Question 14

_{Surgery to the Hip and Femur​- Total Hip Arthroplasty (THA) - Types}

Closed reduction of hip dislocation

^{can be accomplished with which type of anesthetic?}

Answer 14

Usually can be accomplished with very brief anesthetic

Often induce with Propofol and mask patient with gas

May need to use Sux to facilitate reduction if hip musculature severely contractured

Question 15

_{Surgery to the Hip and Femur}

Total Knee Arthroplasty

^{Position/How is blood loss minimized?}

Answer 15

Supine position

Blood loss usually minimized with use of TQ

Not all surgeons use a TQ

Question 16

_{Surgery to the Hip and Femur}

Total Knee Arthroplasty

^{Anesthesia Techniques:}

Answer 16

GA

Neuraxial

Question 17

_{Surgery to the Hip and Femur - Total Knee Arthroplasty - Anesthesia Techniques}

GA with LMA or ETT

^{choice based on:}

Answer 17

As always, make sure your patient is a candidate for LMA

Evaluate risk for aspiration

Question 18

_{Surgery to the Hip and Femur - Total Knee Arthroplasty - Techniques}

Neuraxial:

Answer 18

If cooperative, patients can tolerate neuraxial technique plus sedation

Question 19

_{Surgery to the Hip and Femur - Total Knee Arthroplasty}

Postop pain

^{Facilitated by preop placement of:}

Answer 19

Lumbar epidural or Perineural catheter

Post-op pain is typically more severe than pain following hip arthroplasty

Effective postop analgesia facilitates early physical rehabilitation to maximize postoperative ROM and prevent joint adhesions following knee replacement

Need to balance pain control and patient comfort with the need for patient who is alert and cooperative enough to start their postoperative rehab program

Epidural analgesia is useful for those patient having bilateral knee replacements

Question 20

_{Surgery to the Hip and Femur - Total Knee Arthroplasty - Postop pain}

Lumbar epidurals vs Femoral perineural

^{for unilateral knee replacement, what’s the difference?}

Answer 20

Lumbar epidurals and femoral perineural catheters provide equivalent analgesia!!!

Femoral perineural catheters produce fewer SEs (itching, N/V, urinary retention, orthostatic light-headedness)

Question 21

_{Surgery to the Hip and Femur - Total Knee Arthroplasty - Postop pain}

PNB catheters

^{benefits/consideration/complications:}

Answer 21

In RCTs with continuous PNB catheters that are used postoperatively to deliver a continuous perineural infusion of LA have been shown to decrease the time it takes to meet d/c criteria following a TKR

However, remember that the use of these continuous PNB catheters takes a team approach – all members of HCT need to be involves (PT, nursing, surgery)

Complications can occur, including the major complication of falling!

Need a plan in place for preventing falls in the postop period for patients with these catheters

Important education piece anytime any type of regional anesthetic technique is used

Question 22

_{Surgery to the Hip and Femur}

Knee Arthroscopy

^{intensity/population:}

Answer 22

Relatively minor procedure

Usually performed on outpatient basis

Often thought of as being young and healthy

Many of these patients are elderly and have multiple co-morbidities

Question 23

_{Surgery to the Hip and Femur}

Knee Arthroscopy

^Position:

Answer 23

Supine

Question 24

_{Surgery to the Hip and Femur - Knee Arthroscopy}

Choice of anesthesia techniques:

Answer 24

GA or neuraxial

PNBs using LAs with or without adjuvants + IV sedation

Question 25

_{Surgery to the Hip and Femur - Knee Arthroscopy}

PNBs types of injections:

Answer 25

Periarticular injections

^{=> infiltration of local anesthetics around the join}

Intraarticular injections

^{=> instillation of LA into the joint}

^{Intraarticular LAs (bupivacaine or ropivacaine) usually allow for effective postop pain control for several hours​}

^{Adjuvants to LAs include clonidine, opioids, ketorolac, epinephrine, and neostigmine for intraarticular injections are used to increase the duration of the analgesia​}

Question 26

_{Surgery to the Hip and Femur - Knee Arthroscopy}

Neuraxial vs GA

^{which is better?}

Answer 26

SABs and epidurals seem to have same amount of success and patient satisfaction

But in ambulatory setting, GA is likely preferred as the others can delay d/c home

Question 27

_{Surgery to the Hip and Femur}

ACL Repair

^{procedure intensity compared to knee arthroscopy/population basis:}

Answer 27

More extensive than knee arthroscopy

Outpatient procedure

Question 28

_{Surgery to the Hip and Femur - ACL Repair}

Anesthetic techniques:

Answer 28

GA

Neuraxial

PNB

Lumbar plexus block

^{(psoas compartment block)}

Question 29

_{Surgery to the Hip and Femur - ACL Repair - Anesthetic techniques}

Lumbar plexus block

^{(psoas compartment block)}

^{benefits/risks:}

Answer 29

Combined with spinal or sciatic block dramatically decreases postop opioid requirements

Lumbar plexus block: also known as psoas compartment block; this is an advanced block technique

Because placement of needle is deep in muscles, there is greater risk for systemic toxicity than there is with more superficial techniques

Proximity of lumbar nerve roots to the epidural space also carries risk of epidural spread of the LA

Question 30

_{Surgery on the Lower Extremities}

Anatomy of the Lumbar Plexus

^{How many nerves? where do they originate? what do they innervate?}

Answer 30

Lumbar plexus consists of 5-6 peripheral nerves that have origins in spinal roots L1-L4

The roots divide into the anterior and posterior branches

Small posterior branches supply innervation to skin of lower back and paravertebral muscles

Anterior branches form the lumbar plexus within the substance of the psoas muscle and emerge from the muscle as individual nerves in the pelvis

Question 31

_{Surgery on the Lower Extremities}

Indications for Lumbar plexus block

^{benefits/potential complications:}

Answer 31

Surgery on hip - Anterior thigh - Knee

Provides anesthesia or analgesia to entire distribution of the lumbar plexus, including the anterolateral and medial thigh, the knee, and the saphenous nerve below the knee

When combined with sciatic nerve block, anesthesia of the entire leg can be achieved

Very complex technique involved

Potential for complication and existence of simpler alternatives, weigh risk vs. benefits of lumbar plexus block

Question 32

_{Surgery on the Lower Extremities}

Continuous peripheral nerve block system that slowly infuses local anesthetic near a nerve for effective pain relief:

Answer 32

ON-Q Outpatient Pain Pump

Portable system that delivers LA to surgical site

Pump connects to a catheter that delivers LA to relevant peripheral nerves

Can be used for multiple days

Ideally can reduce use of narcotics

Question 33

_{Surgery on the Lower Extremities - Surgery to the<strong> Ankle</strong> and<strong> Foot</strong>}

Anesthetic techniques:

Answer 33

MAC and local from surgeon

GA

Innervation of foot provided by

^{<strong>(1)<em> femoral nerve</em></strong> (via <u>saphenous</u> nerve) and}

^{(2) <strong><em>sciatic nerve</em></strong> (via <em>posterior tibial</em>, <em>sural</em>, and d<em>eep peroneal</em> nerves)}

Can use PNB at the upper leg, knee or ankle

Can us neuraxial technique for foot surgery

Question 34

_{Surgery on the Lower Extremities - Surgery to the <strong>Ankle </strong>and <strong>Foot</strong>}

Considerations for technique selection

^{based on:}

Answer 34

Selection of regional technique based on surgical site, use of calf or thigh TQ, degree of wt bearing or ambulation, and need for postoperative analgesia

For example, TQ inflation > 15 to 20 minutes requires GA or neuraxial technique

Long-acting local anesthetics and the addition of epinephrine or clonidine allow prolongation of postop analgesia

Additional onset time required for bupivacaine and ropivacaine, so may take longer for block to set up

Question 35

_{Surgery on the Lower Extremities - Postoperative Analgesia}

Systemic analgesics:

Answer 35

Simple

Safe

Non-opioid analgesics

PCA

Question 36

_{Surgery on the Lower Extremities - Postoperative Analgesia}

PCA (patient-controlled analgesia)

^{benefits/concerns:}

Answer 36

Improved analgesia

Decrease in total opioid consumption

Increased patient/nurse satisfaction

Patient education is key

^{(not okay for family member to use device for patient)}

Question 37

_{Surgery on the Lower Extremities - Postoperative Analgesia}

Non-opioid analgesics:

Answer 37

IV acetaminophen, ketorolac, ibuprofen

Gabapentin, clonidine, ketamine, esmolol (delays metabolism of opioids), dexmedetomidine

Improves analgesia, as multimodal approaches are more effective

Avoids side effects of opioids (resp depression, n/v, pruritis)

Question 38

_{Orthopedic surgery - Microvascular Surgery}

Microvascular surgeries

^{Two types:}

Answer 38

Replantation

^{(reattachment of a completely severed body part)}

Revascularization

^{(restoring blood flow thru the severed body part)}

Most replantation surgery involves the upper extremity

Question 39

_{Orthopedic surgery - Microvascular Surgery}

Improving blood flow

^How?

Answer 39

Perfusion pressure

^{Blood flow may be improved by increasing the perfusion pressure, preventing hypothermia, and using vasodilators and sympathetic blockade}

^{Microvascular perfusion pressure depends on both adequate intravascular volume and oncotic pressure; may consider colloid}

Blood loss

^{Blood loss is often continual and insidious}

^{Unrecognized bleeding and third-spacing both reduce perfusion pressure but don’t overcorrect with crystalloid}

^{=> can cause generalized edema (including the replanted body part) AND excess administration of blood products can increase blood viscosity and decrease BF)}

Phenylephrine (+/-)

^{Evidence suggests that using phenylephrine to support BP doesn’t jeopardize blood flow to the tissue being re-implanted}

^{BUT <u>ALWAYS ask surgeon</u> their preference!!!}

Body temp

^{Body temperature impacts blood flow}

^{Avoid hypothermia, as it causes peripheral vasoconstriction, sympathetic activation, shivering, increased O2 demand, altered coagulation, leftward shift of oxygen-hemoglobin dissociation curve (so Hgb less likely to release O2 into the tissues)}

Vasospasm

^{Antithrombotics, fibrinolytics, and smooth muscle relaxants used to preserve blood flow in microvascular anastomoses thus helping to prevent vasospasm}

Question 40

_{Orthopedic surgery - Microvascular Surgery - Improving blood flow}

Perfusion pressure:

Answer 40

Blood flow may be improved by increasing the perfusion pressure, preventing hypothermia, and using vasodilators and sympathetic blockade

Microvascular perfusion pressure depends on both adequate intravascular volume and oncotic pressure; may consider colloid

Question 41

_{Orthopedic surgery - Microvascular Surgery - Improving blood flow}

Blood loss:

Answer 41

Blood loss is often continual and insidious

Unrecognized bleeding and third-spacing both reduce perfusion pressure but don’t overcorrect with crystalloid

=> can cause generalized edema (including the replanted body part) AND excess administration of blood products can increase blood viscosity and decrease BF)

Question 42

_{Orthopedic surgery - Microvascular Surgery - Improving blood flow}

Phenylephrine (+/-)

Answer 42

Evidence suggests that using phenylephrine to support BP doesn’t jeopardize blood flow to the tissue being re-implanted

BUT ALWAYS ask surgeon their preference!!!

Question 43

_{Orthopedic surgery - Microvascular Surgery - Improving blood flow}

Body temperature:

Answer 43

Body temperature impacts blood flow

Avoid hypothermia, as it causes peripheral vasoconstriction, sympathetic activation, shivering, increased O2 demand, altered coagulation, leftward shift of oxygen-hemoglobin dissociation curve (so Hgb less likely to release O2 into the tissues)

Question 44

_{Orthopedic surgery - Microvascular Surgery - Improving blood flow}

Vasospasm:

Answer 44

Antithrombotics, fibrinolytics, and smooth muscle relaxants used to preserve blood flow in microvascular anastomoses thus helping to prevent vasospasm

Question 45

_{Orthopedic surgery - Microvascular Surgery - Anesthetic type}

RA techniques:

Answer 45

RA techniques have several advantages

They provide sympathectomy => vasodilation to the proximal and increased BF

Question 46

_{Orthopedic surgery - Microvascular Surgery - Anesthetic type}

GA

^benefits:

Answer 46

GA ensures airway is secure AND more likely to keep patient from moving

Question 47

_{Orthopedic surgery - Microvascular Surgery - Anesthetic type}

Combination of GA and RA

^{Benefits/concerns:}

Answer 47

Prolong intraoperative anesthesia and postoperative analgesia

Reduces the amount of INH agent needed

Increases patient’s tolerance of long procedure

Regardless of technique, avoid anything that stimulates vasospasm or vasoconstriction (pain, hypotension, hypovolemia)

Question 48

_{Orthopedic surgeries}

Positioning considerations associated with long surgical procedure

Answer 48

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