ADVANCED MED SURG
LEWIS CP 65
CRITICAL CARE
Tidal volume- the amount of air that moves in/out of the lung with ea. Respiratory cycle
SV- stroke volume, the volume of blood pumped out by the left ventricle of the heart during
systolic contraction- this is when the aortic pressure is pumping the blood back to the
peripheral extremities, when the mitral valve closes. SV= EV-PV
SVV- a predictor of fluid responder
Barotrauma- the physical damage to the tissue caused by the difference in gas pressure inside
the body and the outside environment
Volutrauma- a lung injury due to overdistention during ventilation
Pneumothorax- a collapsed lung caused by gas pressure b/w the lungs and the chest wall
Negative pressure ventilation- Low pressure, Air sucked in. The diaphragm contracts and move
down, intercostal muscles move up and out
Positive pressure ventilation- High pressure, Air sucked out, greater pressure then the
surrounding environment
Arterial pressure-based cardiac output- circulating BP against the walls of the vessels (APOC)
 Minimally invasive technique to determine continuous CO/CCO/CCI
 Sensors attaches to arterial pressure lines and a monitor
 Sensors measures arterial pulse pressure
 This can assess a PTs ability to respond to fluids by increasing SV-stroke volume/preload
responsiveness
 SVV= Stroke volume variability, fluid responsiveness
 SV= stroke volume, volume of blood pumped out of the left ventricle of the heart during
each systolic cardiac contraction
 Only used with adult PTs
 Arterial pressure is the force generated by the ejection of blood from the left ventricle
into the arterial circulation
 CO is calculated by multiplying HR and SV
 Age gender height and weight is also considered in the calculations of SV
ASSIST- CONTROL VENTILATION (ACV)
 A ventilator that delivers a present VT at a present frequency
ADVANCED MED SURG
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When a PT breathes the machine delivers the present VT, it doesn’t allow the PT to
breath slower than the set rate
Potential for hyperventilation and hypoventilation if rate is set too low
Vigilant assessment and monitoring of ventilatory status is necessary
Possible causes of high-pressure alarms are secretions, coughing gagging condensation
and kinks, biting tube, resistance, ARDS, tube too far right
Possible low-pressure alarms, total/partial disconnection, loss of airway tube leakage
SYNCHRONIZED INTERMITTENT MANDATORY VENTILATION
 Works in synthetization with the PTs breathing
 Receiving present FiO2 but self-regulating the rate
 Used for continuous ventilation and weaning a PT off ventilation
 Demands for close monitoring cause ventilations rate may be too late
Pressure support ventilation (PSV)
 The use of positive pressure during inspiration
 Only in assistance to a PT that can initiate respirations
 Also used during weaning