Obtain consent if able
Obtain continuous cardiorespiratory monitoring
Arterial line is ideal if time permits
Consider sedation or local anesthesia if time permits and patient is conscious
Do not delay procedure in unstable patient
For apical approach:
Bed to 45˚ angle if patient condition allows
Brings heart closer to anterior chest wall
For subxiphoid approach:
Bed flat
NG tube to decompress stomach if time permits
Skin prep with iodine or chlorhexidine
Drape appropriately
Consider atropine to prevent vasovagal reaction
Arterial line is ideal if time permits
Do not delay procedure in unstable patient
Bed to 45˚ angle if patient condition allows
Brings heart closer to anterior chest wall
Brings heart closer to anterior chest wall
Bed flat
Pericardiocentesis
Thoracotomy 
Thoracotomy
Thoracentesis
Thoracic lavage
Vasopressors
Transvenous pacing
Needle cricothyrotomy