Positioning Flashcards
AANA Standard 8
Positioning
Most Common Nerve Injuries
Ulnar nerve
Brachial plexus
Nerve Injury Mechanisms
Compression, transection, stretch, traction
Direct or indirect nerve sheath ischemia
Integumentary RISK
Elderly Diabetes PVD Surgical time Chronic hypertension Obesity ↑temperature
Supine Pressure Points
Occiput (head) Scapula (shoulders) Vertebrae (spine) Olecranon (elbow) Sacrum Coccyx Calves Calcaneum (heels)
Supine
Arms lateral or abducted <90° - Avoid brachial plexus stretch - Palms facing towards thighs/trunk Supinated forearm - Pronation → ulnar nerve compression Legs flat & uncrossed Consider lumbar support Pad heels & elbows (ulnar nerve)
Supine Respiratory
↓TLC & FRC
Diaphragm shifts cephalad
Prone
Ventral decubitus
Often intubated
Arms <90°
Spine, buttocks, rectum or peri-rectal, ankle, intracranial surgeries
Prone CV
Blood pooling in abdomen & LE
Inferior vena cava compression
Epidural engorgement
Prone Respiratory
↓compliance (chest not freely hanging)
↑FRC d/t improved posterior lung ventilation
POVL
Postop vision loss Prolonged surgical time spine surgeries (prone) CRAO - central retinal artery occlusion CRVO - central retinal vein occlusion ION - ischemic optic neuropathy Cortical blindness
Most Common POVL
Ischemic optic neuropathy ION
- Extended surgical time
- Blood loss
- Obesity
- Male
- Wilson frame
- Ocular perfusion pressure OPP = MAP - IOP
POVL Prevention
Surgical duration <6hr
10-15° HOB elevation to reduce orbital edema
Maintain BP w/in 20% baseline
Hct >25
CRAO
Eye stroke
Sudden, profound vision loss
Painless blindness
Cherry red macula
CRVO
Eye DVT
Variable blurred vision to sudden vision loss
Optic disk edema
Diffuse retinal hemorrhages
- Hyper coagulable states
- Glaucoma
- Thyroid vein compression or orbital tumors
Lithotomy
Legs abducted & elevated
- Raise & lower legs together to prevent hip injury
Ensure fingers free from footboard
Peroneal nerve injury risk
Hip flexion → sciatic stretch or femoral nerve palsy
Perineal, gynecological, & urology surgeries
Lithotomy CV
↑blood volume d/t shift
Autotransfusion 250-300mL/leg
Lithotomy Respiratory
↓FRC 20%
↓VC
Hypoventilation when breathing spontaneously
Lateral
Head neutral & supported
Shoulders, head, hips, & legs aligned
Ensure eyes, ears, & face are pressure free
Dependent arm on padded board or perpendicular to torso <90°
Axillary roll under dependent side
Shoulder, orthopedic (hip), thorax, & kidney surgeries
Lateral CV
Minimal changes
Kidney rest - vessels compressed ↓VR
Lateral Respiratory
V/Q mismatch
↑FRC non-dependent lung
↓FRC dependent lung
Dependent lung prone to atelectasis & fluid accumulation
Sitting
HOB 30-90°
Ensure at least 2 fingerbreadths b/w neck & mandible
Pad heels & flex legs to prevent sciatic stretch
Arms secured to padded arm boards or lay across patient lap w/ draw sheet
Cervical spine, shoulder, posterior fossa, & breast reconstruction surgeries
Sitting CV
↓SV/CO up to 20%
↓MAP/CVP
Lower extremity venous pooling
↓cerebral perfusion CPP = MAP - ICP
Sitting Respiratory
↑FRC
↑compliance
Sitting Complications
VAE - venous air embolus d/t negative pressure gradient
Pneumocephalus often benign
- Air enters open dura, CSF drainage, surgical decompression
Quadriplegia d/t spinal cord stretch when head flex & loss autoregulation w/ general anesthesia
- Ensure 2 fingerbreadths to prevent strain at C5
Trendelenburg
Dependent edema
↑ICP/IOP
↑CVP
Shoulder braces → brachial plexus stretch or compression
Reverse Trendelenburg
Bed flat w/ head up ↓ICP/IOP ↓CPP/BP ↑pulmonary compliance ↑FRC
Brachial Plexus
Most common nerve injury Supine when arms abducted >90° Humeral head rotation Lateral decubitus - stretch, traction, tension Chest dependent compression
