Orthopedics Flashcards
orthopedics - the largest post-operative problem is ________
post-operative pain
rheumatoid arthritic versus osteoarthritis
- rheumatoid: inflammation of synovial membrane, can have some bone erosion
- osteoarthritis: wearing down of cartilage membrane
where should the endotracheal tube end on a sitting X-ray?
where the clavicles join
rheumatoid arthritis
- limited neck movement: synovitis of cervical spine, TMJ, larynx, pulmonary system and inflammation of intervertebral discs and atlanto-occipital subluxation
- limited TMJ opening
- pulmonary lesions
- hoarseness and inspiratory stridor may indicate a narrowing or fixation of glottic opening due to cricoarytenoid arthritis
*awake fiberoptic intubation
ankylosing spondylitis
- chronic inflammatory process, primarily in spine
- associated with conduction delays, valve lesions, restrictive lungs disease
- concern for cervical spine positioning, airway, and respiratory system
- awake fiberoptic intubation
tourniquet positioning and application
- should cover <50% of the extremity
- padded
- off neurovascular bundles
- exsanguination prior to inflation with esmark
- 90-100 mmHg above SBP
tourniquet hazards - neurological
- abolish SSEP at 30 min
- pain at 60 min
- neuropraxia at 120 min
- nerve injury at edge of tourniquet
tourniquet hazards - muscle
- cellular hypoxia at 2 min
- creatinine value decrease
- cellular acidosis
- endothelial capillary leak at 120 min
tourniquet - systemic effects
- 300-500 cc blood added to circulation
- increased systemic and pulmonary pressures
tourniquet deflation
- fall in core temperature
- metabolic acidosis
- increase ETCO2
- decrease in pulmonary and systemic BP
- fall in MVO2
*takes 20 min for effects to resolve if 1 hour of tourniquet time
tourniquet safety
- do not exceed 2 hours
- nerve damage after 4 hours
- muscle power reduced for a week after 3 hours
bier block steps
- iv
- double tourniquet
- exsanguination with Esmark
- inflate cuff
- inject local anesthetic
- inflate distal cuff, after 20 min can reinflate distal cuff and deflate proximal cuff
- deflate cuff in stages
- remove iv and apply pressure
complications from intravenous regional anesthetic
- hematoma
- systemic toxicity of local anesthetic
- engorgement of the extremity
- ecchymosis and subcutaneous hemorrhage
positioning risks/hazards - beach chair
- cervical neck injury due to dislodgement of head from holder
- inadvertent extubation by surgical team
- brachial plexus injury on contralateral side
- CVP, MAP, PAP, CO, venous return decrease
- CPP decreases and autoregulation is hindered
- PVR, TPR increased but blunted by volatile anesthetics
positioning advantages - beach chair
- reduced rate of brachial plexus injuries
- better respiratory mechanics
- excellent access to shoulder
- weight of arm distracts shoulder joint
blood pressure change with distance
1 mm Hg = 1.25 cm
2-3 mm Hg = 1 inch
where do you measure the blood pressure in the brain?
auditory meatus
positioning risks/hazards - prone
-vision loss
recommendations to avoid post operative vision loss
- avoid direct pressure, hypotension, anemia, large infusions of crystalloid
- consider slight reverse Trendelenburg
MMA cement - risk reduction strategies
- increase FiO2
- euvolemic
- vent distal femur
- high pressure lavage
- use uncemented components
MMA cement - mechanism of action
- exothermic reaction leads to hardening and expansion of cement
- can cause intramedullary HTN and embolization of fat, bone, cement, air
MMA cement - bone cement implantation syndrome
- hypotension
- pulmonary HTN
- arrhythmias
- hypoxia
- decreased CO
scoliosis surgery
- anterior/posterior surgery, requires thoracotomy
- may have restrictive lung disease
- use SSEP
fat embolism
- s/s: dyspnea, confusion, petechiae
- thrombocytopenia
- decrease ETCO2, SaO2, increase PAP
- cardiac ischemia
TXA dosing
- 1g prior to incision and 1g at tourniquet release
- 2g single dose for causes with no tourniquet
- 2g/100ml saline wound soak for 5 min
TXA exclusion criteria
- DVT or PE within 12 months
- congenital thrombophilia
- cardiac stent or ischemic stroke with 12 months
TXA relative contraindications
- renal impairment: creatinine>1.5
- ischemic heart disease
- DIC
- seizures
- history of thromboembolic or vascular disease
TXA mechanism of action, metabolism, duration
- blocks activation of plasminogen
- half-lie 2-3 hours
- urinary excretion, not metabolized
