Test 1: Anesthesia for Orthopedic Surgery Total Hip Arthroplasty, Knee, Ankle, and Foot Flashcards
Total Hip Arthroplasty Etiology
- Osteoarthritis (most commmon)
- Rheumatoid Arthritis (most common)
- Degenerative Synovium or Cartilage Disease
- Avascular Necrosis
- Tumors
- Congenital Deformity
- Dislocation
- Failed Reconstruction
Pre-op considerations for Total Hip Arthroplasty
- Mental status- Confusion / delirium
- Labs - Hgb & Hct, Coagulation, 2 large bore IVs
- Medications
- Typical assessment
Three potentially life-threatening
complications of THA
- Bone cement implantation syndrome (BCIS)
- Intra- and postoperative hemorrhage
- Venous thromboembolism (VTE)
Have 2 units of blood in the cooler ready to go just in case
THA positioning
- Lateral decubitus
- Operative side up
- Padding
- Axillary roll
What is required for general anesthesia for THA
Muscle relaxation
Benfits of Neuraxial Anesthesia in THA
- Decreased EBL
- Decreased DVT & PE incidence
- Decreased incidence of postop delirium
MUST know coagulation status
Name of cement used for fixation of prosthetic and complications
- PolyMethylMethAcrylate (PMMA)
- Results in intramedullary HTN > 500 mmHg when heated
- Embolization of fat, bone marrow, or cement
PolyMethylMethAcrylate (PMMA) can cause
- Releases heat (Exothermic Reaction)
- Systemic absorption causing - Vasodilation, Decreased SVR
- Platelet aggregation R/T tissue thromboplastin release
- Microthrombus in lungs
- CV instability
Bone Cement Implantation Syndrome (BCIS)
Bone Cement Implantation Syndrome (BCIS) prevention
- Minimize hypotension & hypovolemia
- Maximize FiO2 (100%) & SpO2
- Vent hole in femur
- Lavage of femoral shaft
- Avoid bone cement
S/S of Bone Cement Implantation Syndrome (BCIS)
- Hypoxia
- Hypotension
- Arrhythmias
- Pulmonary HTN
- Decreased cardiac output
Bone Cement Implantation Syndrome
(BCIS) treatment
- Increased FiO2
- Maintain euvolemia
- Manage hypotension with vasopressors
Post op considerations for THA
- Pain management
- Mental status
Most common complications in THA
- Cardiac events
- PE
- Pneumonia
- Respiratory failure
- Infection
Hip Arthroscopy indications
- Femoro-acetabular impingement
- Acetabular labral tears
- Loose bodies
- Osteoarthritis
Hip Arthroscopy positioning
- Supine
- Weighted traction
Cardiac consideration for patient in supine position
- equalization of pressures throughout the arterial system
- increased right-sided filling and cardiac output
- decreased heart rate and peripheral vascular resistance (PVR)
Respiratory consideration for patient in supine position
- Gravity increases perfusion of dependent (posterior) lung segments
- abdominal viscera displace diaphragm cephalad
- Spontaneous ventilation favors dependent lung segments, while closing volumes favors independent (anterior) segments
- FRC decreases (~800 mL) and may fall below closing volumes in older patients
- further exacerbated by an enlarged abdomen such as with obesity, pregnancy, or ascites.
The most common postoperative peripheral neuropathy?
Ulnar Nerve Neuropathy
The two major sites of injury are the elbow at the
Condylar groove and the cubital tunnel
The condylar groove is formed by
- Medial epicondyle of the humerus
- Olecranon process of the ulna.
The ulnar nerve is shallow at this point, pre-disposing to compression injury, especially in males where there is less protective adipose tissue (mines all muscle)
Why is neuraxial anesthesia not usually considered with hip arthroscopy?
- Most of the time this is an outpatient procedure
- Neuraxial anesthesia may prolong time to discharge
Hip Arthroscopy post op considerations
- Assess for nerve injury
- Pain management
- Mental status
How are Hip Dislocation done
- Require closed reduction
The most common type, can do open if there is occult bleeding
Hip Dislocation pre-op considerations
- NPO status
- Comorbidities
- IVF status
Hip Dislocation anesthesia management
- May be performed in ER
- “Conscious sedation”- Ketamine /Propofol mix
- Muscle relaxation- Succinylcholine
Hip Dislocation post-op
- May be admitted for observation
- Pain management
- Mental status
Knee Arthroscopy pre-op based on:
- Age of patient
- Healthy young athlete = Ligament tears
- Healthy elderly
- Patient with comorbidities
Knee Arthroscopy Positioning
- Supine
- Knee flexed
Knee Arthroscopy Anesthesia
Management
- General anesthesia-LMA?
- Neuraxial / regional anesthesia
- Spinal may delay discharge (not done much)
- Sedation with extraarticular & intraarticular injections
- Tourniquet applied depending on procedure
Knee Arthroscopy post op
- Outpatient surgery
- Pain management
- Peripheral nerve block
- Injections by surgeon
Total Knee Arthroplasty pre-op
- Mental status
- Confusion/delirium
- Labs-Hgb & Hct, Coagulation
- Medications
- Typical assessment
Total Knee Arthroplasty Positioning
- Supine
Total Knee Arthroplasty
Anesthesia Management
- General anesthesia
- Neuraxial anesthesia -Preferred due to Decreased 30-day mortality, Decreased infection rate
- Peripheral nerve block- Femoral, Sciatic
80% aortic stenosis contraindication for spinal
Tourniquet considerations with TKA
- Blood loss begins with deflation and continues x 24 hrs
- Risk of peroneal nerve palsy (make sure patient can dorsiflex the feet)
- Significant postop pain
Make sure patient can dorsal flex their feet
4 Artificial Components for TKA
- Tibial component
- Femoral component
- Patellar component
- Plastic spacer
TKA post op
- Significant pain
- Indwelling epidural catheter
- Continuous peripheral nerve block
- Mental status
Wound infection Prevention
- Decreased traffic in & out of the OR
- Prep & drape
- Preop antibiotics
- Use of hoods
Wound infection is Increased with
- Poor peri-operative glucose control
- Post-op hypoxia
- Post-op hypothermia
Amputations pre-op
- Comorbidities
- Diabetic
- FBS (Fast blood glucose)
- Pressure ulcers
- Full sensory assessment
- Psychosocial
- Psychological support
Amputations Positioning
- Supine
- Padding- Obese, Cachectic
Amputations Anesthesia Management
- General anesthesia
- Neuraxial anesthesia- Preferred, Decreased incidence
of delirium, and Less phantom pain? - Tourniquet applied –variable decrease Blood loss
Amputations post op
- Pain management
- Mental status- Confusion,Delirium
- Psychological support
Phantom pain
- Onset within few days of surgery
- Intermittent
- Shooting, stabbing, squeezing, burning, throbbing
Phantom pain triggers
- Weather changes
- Emotional stress
- Pressure on remaining area
Causes of phantom pain is due to
- Remapping of circuitry
- Damaged nerve endings
- Scar tissue
- Physical memory
- Pain prior to amputation
MRI/PET to help diagnosis
Phantom pain treatment
- Biofeedback
- Relaxation
- Massage
- TENS unit
Phantom pain treatment medications
- Neuroleptics
- Antidepressants,
- Sodium channel blockers
Types of Ankle/Foot procdures
- Achilles tendon
- ORIF malleolar fracture
- Hallux valgus (Bunions)
Ankle/Foot pre-op
- Based on age of patient
- Comorbidities
- Anxiety
- Pain
Ankle/Foot Positioning
- Achilles tendon-Lateral, Prone
- All others-Supine
Ankle/Foot Anesthesia Management
- General
- Neuraxial
- Regional
- Ankle block for foot surgery
- Current level of sensation
- Maybe injected by podiatrist
Posterior tibial nerve
Sensation to plantar surface
Saphenous nerve
Innervates medial malleolus
Deep peroneal nerve
Interspace b/t great & 2nd toes
Superficial peroneal nerve
Dorsum of foot & 2nd-5th toes
Sural nerve
Lateral foot & lateral 5th toe
Ankle/Foot post-op pain
- Pain management
- Immobilization
- Outpatient surgery
Ask if they are going to splint or casted
