Anesthesia for
Orthopedic surgery
อรุ ณชัย นรเศรษฐกมล
Content

General consideration




Age-specific orthopedic conditions
Medical comorbidities
Coexisting medication
Specific consideration





Positioning
Bone cement
Pneumatic tourniquet
Fat embolism
Deep vein thrombosis &
Thromboembolism
Age-specific orthopedic
condition

Young adult


ACL reconstruction, Rotator cuff
Elderly
Hip, Knee arthroplasty
 Hip Fracture


Children

Congenital orthopedic surgery
Medical comorbidities

Elderly patients




Multiple organ dysfunction
Rheumatoid arthritis
Osteoarthritis
Ankylosing spondylitis
Rheumatoid arthritis
problem should be aware






Cervical spine instability
IV access
Systemic involvement
Airway management
Spinal or epidural may be
difficult
Positioning
Osteoarthritis
Joint usually involved in
Osteoarthritis
Osteoarthritis ( OA)
problem should be aware






Reduced joint movement
Airway management
IV access
Spinal or epidural may be
difficult
Positioning
Concurrent analgesic therapy
Ankylosing spondylitis (AS)
problem should be aware



Fix flexion deformity
Regional anesthesia may be
difficult
Abnormal spread of local
anesthetics
Coexisting medication






Antihypertensive drugs
Steroids
Aspirin
NSAIDs
Opioid analgesics
Immunosuppressive drugs
Specific consideration
Positioning





Supine
Lateral
Prone
Beach chair
Fracture table
Why is positioning important?




Enable IV and catheter to remain
patent
Enable monitors to function properly
Facilitates the surgeon’s approach
Patient safety
Supine


Patient on back
Arms on arm boards
Arm < 90 degrees
 Arm is supinated ( palm up)
 Place padding under elbow if able


Arm tucked
Check fingers
 Check IV lines and SaO2 probe

Lateral

Body alignment
Keep neck in neutral position
 Always place axillary roll
 Place padding between knees
 Place padding below lateral
aspect of dependent leg

Lateral

Position arms to parallel to one
another

Place padding between arms or
place non-dependent arm on
padded surface
Prone


Face down
Head placement

Head straight forward



ET tube placement and patency
Check bilateral eyes/ears for pressure points
Head turned


Check dependent eye/ear, ETT placement
Be aware of potential vascular occlusion
Prone

Arm placement
Tucked – similar to supine
 Abducted

Check neck rotation and arm extension
to avoid brachial plexus injury
 Elbow are padded



Chest rolls
Iliac support

Padding in placed under iliac crests
Injury occuring from prolonged
positioning


Eye compression in prone
position
Skin breakdown due to
prolonged positioning
Bone cement
Polymethylmethacrylate: MMA
Bone cement implantation
syndrome ( BCIS)




Release of vasoactive and
myocardial depressant substances
Intravascular thrombin generation in
the lungs
Direct vasoactive effects of
absorbed MMA
Acute pulmonary microembolization
Clinical presentation









Fever
Hypoxia
Hypotension
Tachycardia
Dysrhythmia
Mental status change
Dyspnea
End tidal CO2 decrease
Right ventricular failure and cardiac
arrest
Management

Supportive care
Monitoring vital signs
 O2 supplement
 IV fluid
 Vasopressor

Pneumatic tourniquet


No more than 2 hours
100 mmHg above systolic blood
pressure
250 mmHg for arm
 350 mmHg for leg

Pneumatic tourniquet

Advantage


Eliminate intraoperative bleeding
Disadvantages
Neurologic effect
 Muscle change
 Systemic effects of the tourniquet
inflation
 Syeyemic effects of the tourniquet
release

Neurologic effects



Tourniquet pain and
hypertension If > 45-60 mins
Neurapraxia if > 2 hours
Nerve injury at the skin level the
edge of the tourniquet
Muscle changes




Cellular hypoxia
Cellular acidosis
Endothelial capillary leak
Limb becomes colder
Systemic effect of tourniquet
inflation

Arterial pressure elevated
Systemic effect of tourniquet
release

Transient fall in core temperature

Transient metabolic acidosis
Release of acid metabolites into
central circulation
Transient fall in arterial pressure
Transient increase in EtCO2



Prevention

Select patients
Wide, low-pressure cuff
Apply the lowest pressure to prevent
bleeding
Limit time to 2 hours

Set maximum pressure






Arm 50-75 mmHg above systolic
Leg 75-100 mmHg above systolic
Adequate padding underneath
Fat embolism


The mechanical theory
The biochemical theory
Clinical finding

Cardiovascular


Respiratory


Retinal hemorrhage
Cutaneous


Delirium stupor seizure coma
Ophthalmic


Dyspnea hypoxia hemoptysis
Cerebral


Persistent tachycardia, hypotension
petechiae
Other

Jaundice fever
Treatment

Prophylactic


Early stabilization of the fracture
Supportive

Respiratory care


Maximize O2, ventilation
Invasive monitor

Volume status
Inotrope
 High dose corticosteroid

Deep vein thrombosis &
Thromboembolism
lower extremities, pelvis

Major pathophysiological
mechanism
Venous stasis
 Hypercoagulable state
 Endothelial damage

Risk Factor






Obesity
Age > 60 years
Procedure > 30 mins
Use of tourniquet
Lower extremities fracture
Immobilization > 4 days
Prevention

Prophylactic anticoagulant
Low dose heparin
 Warfarin
 LMWH



Intermittent pneumatic
compression
Neuraxial anesthesia reduce
thromboembolic complication
Major orthopedic procedure




Total hip replacement
Fracture of the hip
Total knee replacement
Spinal surgery
Hip surgery

Patient
Limit ability to exercise
 Cardiovascular function can be
difficult to assess
 Elderly with systemic disease,
OA,RA


Blood loss

Use of hypotensive technique or
reginal anesthesia reduces blood
loss

Positioning
Mostly lateral decubitus position
 Ventilation perfusion mismatch
 Neurovascular problem

Potentially life-threatening
complication



Bone cement implantation
syndrome
Intra and postoperative
hemorrhage
Venous thromboembolism
Important factor of mortality







Very old age
Female>male
Hip fracture
Obesity
Smoking
Malnutrition
Baseline cardiopulmonary function
Anesthetic concerns





Invasive monitoring
Blood loss
Positioning
Cement fixation
Deliberate hypotension
GA or RA





GA
Decrease lung
function
Depress cough
Increase
secretion
Depress cardiac
function





RA
Reduce lung
complication
Reduce
thromboemboli
Reduce delirium
Reduce blood
loss
Revision hip arthroplasty



Blood loss
Longer duration
Deliberate hypotension or
regional should be used
Total knee arthroplasty

Preoperative consideration
Same as THR
 Severe rheumatoid arthritis
 Osteoarthritis
 Obesity
 comorbidity

Anesthetic management





Thromboembolism
Fat embolism
Cement
Postoperative blood loss
Postoperative pain; more than
THR