Test 2 Flashcards
Lesson 1 and 3, modes
Cardiovascular Complication of mech vent
Reduced venous return, reduced cardiac output, hypotension
Airway Complication of mech vent
Contamination of lower resp tract
Gastrointestinal Complication of mech vent
nutritional deficiency
Renal complication of mech vent
decreased atrial natriuretic peptide, reduced urine output, increased antidiuretic hormone
Neuromuscular of mech vent
Sleep deprivation, Increased intracranial pressure, critical illness weekness
VILI
- Overdistention of alveoli causing damage and release of excessive inflammatory cytokines
- Barotrauma
VAP
- Often the result of aspiration of oral secretions and bacteria
- Increase head of bed, limit circuit changes to as needed
CMV Mode
- Acutely Ill patients
- Full Support
- All breaths mandatory
IMV
- Post Op Patients
- Partial support
- Combination of mandatory and spontaneous breaths
Ventilator monitors and adjusts airway pressure needed to deliver target volume
PRVC
PC modification of SIMV allows patient to breathe spontaneously throughout the set pressure
APRV
Uses artificial intelligence to titrate the level of respiratory support based on patient parameters
ASV
Control mode provides support in proportion to the neural output of the respiratory center of brain
PAV
Triggered, limited, and cycle by the electrical activity of the diaphragm
Neurally adjusted ventilatory assist
Dual Control
- Dual control is a more sophisticated version of setpoint control.
- Dual control allows the mechanical ventilator to switch between volume and pressure control during inspiration in accordance with clinician-established priorities.
- What may initially begin as a volume control breath may switch to pressure control.
Setpoint Control
Output is manipulated to match a constant preset input, allowing for VC or PC breaths
Intelligent Control
Uses automatic control and artificial intelligence to measure patient variables such as RR and PETCO
-These measurements are then used by the machine to adapt variables such as pressure to maintain patients in a designated “comfort zone.”
Servo Control
Dynamic and fluctuates on demand
-The machine output follows and amplifies the patient’s own flow pattern, allowing support to overcome abnormal respiratory workloads due to disease or artificial airways.
Adaptive Control
Allows automatic adjustment of one target variable over several breaths
PSV
- Pressure support used to help overcome work of breathing
- Little of no ventilatory support
CPAP
- Prevent alveolar collapse
- improve oxygenation
Respiratory Failure
is a general term used to describe any clinical situation in which inadequate gas exchange occurs in the lungs.
Respiratory failure is divided into two major categories, each of which includes many different diseases and conditions that can lead to respiratory failure.
- Type 1 Respiratory failure: Hypoxemic Resp Failure
- Type II Respiratory failure: Hypercapnic Resp Failure
Hypoxemic Resp Failure
involves inadequate blood oxygenation and low to normal levels of carbon dioxide. (oxygenation failure)
Hypercapnic Resp Failure
involves inadequate blood oxygenation with high levels of carbon dioxide. This condition is also referred to as ventilatory failure.
Patients with neuromuscular disease often present with an inability to
Achieve ideal tidal volumes
-Typically these patients breathe very shallowly and with higher respiratory rates than normal in order to try to maintain adequate ventilation.
Guarded Breathing
Less extensive trauma such as broken ribs may cause a patient to breathe shallowly to prevent exacerbation of pain
-can result in hypoventilation, which then progressives to resp failure
Patients with chronic lung disease may progress to respiratory failure as a result of a
comorbid infection, prolonged increased WOB that leads to fatigue, or damaged alveoli that impair normal gas exchange. Chronic lung disease does not usually result in pain during deep breathing.
What may contribute to respiratory failure in a patient who was in a very serious motor vehicle accident that resulted in critical injuries to the head and chest?
- Pain associated with deep breathing due to broken ribs and injured thoracic muscles
- Reduced ventilatory drive
refers to the various methods of therapeutic life support that involve the use of machines
Mechanical Ventilation: the machines help control a patient’s breathing with the goal of improving gas exchange and alleviating stress on the respiratory muscles.
These four broad conditions are considered the primary indicators for mechanical ventilation:
- Apnea
- Acute ventilatory failure
- Impending ventilatory failure
- Severe oxygenation defect
defined as rising Paco2 with a corresponding decrease in pH, causing an acidic condition in the blood known as respiratory acidosis.
Ventilatory Failure
A severe oxygenation defect is when blood oxygen levels are unresponsive or refractory to supplemental oxygen
Refractory Hypoxemia
The primary goal of mechanical ventilation
is to provide adequate oxygenation and alveolar ventilation to maintain normal blood oxygen and carbon dioxide levels.
Inspiratory limb
elivers medical gas to the patient through an artificial airway such as an endotracheal tube or tracheostomy tube.
expiratory limb
which delivers exhaled gases from the patient back to the ventilator to be measured.
VILI stands for
Ventilator-induced Lung Injury
Various VAP prevention strategies include:
- Elevating the head of the bed
- Frequent oral care
- Careful management of the airway cuff pressure
- Limiting circuit changes to an as-needed basis
- Use of specially designed antimicrobial endotracheal tubes
A mode of ventilation can be described by
specific combination of control variables, breathing sequence, and targeting scheme used to achieve these goals.
Control Variable
which is pressure or volume
- is the designated independent variable between pressure, volume, and flow as they relate to the equation of motion.
- If volume is the designated control variable, the shape of the pressure waveform is dependent on the volume setting and the resistance and compliance of the respiratory system. Volume is constant and pressure varies.
Breath Sequence
which is a pattern of mandatory or spontaneous breaths
Targeting Scheme
Which is the feedback control scheme used to shape the breath and determine the breathing sequence
___ is constant and ___ varies
Volume is constant and pressure varies.
Breath sequence can be subdivided into three categories:
- Continuous mandatory ventilation (CMV), where all breaths are mandatory
- Intermittent mandatory ventilation (IMV), where breaths can be mandatory or spontaneous
- Continuous spontaneous ventilation (CSV), where all breaths are spontaneous
CMV
Continuous Mandatory Ventilation; Where all breaths are mandatory
- is operated as volume control (VC-CMV) or pressure control (PC-CMV). Although every breath is mandatory, patients are capable of triggering a mandatory breath above the set rate.
- Because CMV is considered a full support method of mechanical ventilation, it is rare that the rate is set so low that a patient would hypoventilate in the event of apnea.
IMV
Intermittent Mandatory Ventilation; where all breaths can be mandatory or spontaneous
- Like CMV, IMV can be volume controlled (VC-IMV) or pressure controlled (PC-IMV)
- SIMV
CSV
Continuous Spontaneous Ventilation; where all breaths are spontaneous
- used for patients who require little to no ventilatory support and is often used to evaluate a patient’s ability to breathe spontaneously when considerating discontinuation of ventilatory support.
- pressure support (PS) can be applied to help overcome some of the work of breathing created by the artificial airway and the patient circuit.
- Continuous positive airway pressure (CPAP) or positive end-expiratory pressure (PEEP) can be set at minimal levels to prevent alveolar collapse and to improve oxygenation.
The control variable can be identified by looking at the ventilator’s
output waveforms (or by vents labels)
If volume is the control variable,
reductions in compliance or increases in resistance will result in maintenance of the set volume at the expense of higher airway pressures and potential lung injury.