Initiation and Modification of Initiation and Modification of Therapeutic ProceduresTherapeutic Procedures
Achieve Adequate Respiratory Support
Instruct Patients in Deep Breathing / Muscle Training
Used in Acute Care:Aid secretion clearancePrevent or treat post-op atelectasisImprove aerosol drug deliveryUsed in rehabilitation to improve:Efficiency of ventilationExercise tolerance
Instruct Patients in Deep Breathing / Muscle TrainingDeep Breathing Exercises:Inspiratory Breathing Exercises
Diaphragmatic (abdominal) breathing Lateral costal breathing
Promote effective use of diaphragm Improve efficiency of ventilation by increasing VT and
decreasing respiratory rate
Expiratory Breathing Exercises Pursed-lip breathing
Increases back pressure in the airways during exhalation
Can help lessen air-trapping
Instruct Patients in Deep Breathing / Muscle TrainingIncentive SpirometryUsed primarily in the acute care setting for patients at risk for or diagnosed with atelectasis, (typically following thoracic or abdominal surgery)If the patient cannot cooperate or cannot generate an inspiratory capacity at least 33% of predicted, recommend IPPB as an alternativeRecommend discontinuation when clinical signs indicate resolution of atelectasis
Resolution of fever Improvement of breath sounds Normal chest X-ray Improved arterial oxygenation
Inspiratory Muscle Training Techniques (IMT)have largely replaced manual breathing exercises as the method of choice for COPD patients.Flow and threshold resistors
Initiate and Adjust Mechanical VentilationIPPB Therapy
Indicated to:Improve lung expansion in patients with atelectasis who cannot use other methods, such as incentive spirometry.Aid in delivery of aerosolized drugs (usually when other methods have failed)Provide short-term ventilatory support for patients with acute hypercapnic respiratory failure or chronic muscle weakness
Only absolute contraindication:Untreated pneumothorax
IPPB initial settings:Sensitivity of about -2 cm H2OCycle pressure between 10 and 20 cm H2O with a moderate flowApproximate the O2% during the IPPB to the patient’s O2 therapy prescription
Attach to O2 blender with machine set to deliver pure source gas to deliver precise FiO2
Goal
To achieve quick and near-effortless on-triggering, followed by a relatively rapid pressure rise and ending in a short plateau.
Initiate and Adjust Mechanical VentilationContinuous Mechanical Ventilation SettingsCandidates who cannot properly select appropriate modes and set and adjust ventilator parameters will not be able to pass the CRT examThe NBRC hospital expects you to be familiar with:All common modes, including control mode, assist/control mode, SIMV, pressure support ventilation, CPAP, and bi-level positive airway pressure (BiPAP)Dual breath modes such as pressure-regulated volume control (PRVC) and airway pressure release ventilation (APRV)
MODES Mechanical ventilation should be tailored to each patient’s
needs In the early stages of acute respiratory failure, you should
select or recommend a mode that provides full ventilatory support (A/C or normal-rate SIMV)
As patient improves and is able to carry more of the ventilatory load, you should begin using modes that allow or encourage spontaneous breathing (partial ventilatory support)
NBRC hospital Expect the NBRC to emphasize selection of either volume-
or pressure-oriented assist/control or SIMV (with or without pressure support) for most patients needing ventilatory support
Also apply PEEP to patients if they require more than 50% O2 to maintain adequate arterial oxygenation
CPAP (with backup ventilation) is the mode of choice for critically ill patients who have adequate ventilation but who due to shunting need extra support for oxygenation
Select volume-targeted ventilation if CO2 elimination is the primary goal and the patient comfort and lung distention are secondary issues.Select pressure-targeted ventilation if patient-ventilator synchrony is important and CO2 elimination is of lesser concern.Primary goals for adjusting ventilator settings:Achieve acceptable arterial blood gasesMinimize dyspnea, accessory muscle use, and paradoxical breathing.Review AARC Clinical Practice Guidelines for initial adult ventilator settings and adjustments.
Initiate and Adjust Mechanical VentilationNoninvasive Ventilation
The delivery of assisted mechanical ventilation without the need for an artificial tracheal airway.
Negative Pressure: iron lung or tank ventilator, chest curiass, pneumosuitPositive Pressure: bi-level positive pressure support
Application of NPPV requires that the patient have control over upper airway function, be able to manage secretions, and be cooperative and motivated.
Initiate and Adjust Mechanical VentilationElevated Baseline Pressure (CPAP, PEEP)CPAP
Mode of ventilation Involves spontaneous breathing at an elevated baseline
pressuure Indicated to treat sleep apnea, acute cardiogenic pulmonary
edema, manage refractory hypoxemia in patients with adequate ventilation
PEEP Add-on that can be applied to any mode Used in patients for whom additional “machine” breaths are
needed to assure adequate ventilation Helps lower FiO2 needs Helps improve patient-ventilator synchrony (by decreasing
auto-PEEP)
NBRC Hospital standard of care is the application of low levels of PEEP (typically 5 cm H2O) to all adult patients receiving ventilatory support.Helps maintain FRC and prevent airway closure/auto-PEEPMaximize benefits and minimize risks to patient by determining “optimum” PEEPFour methods to determine optimum PEEP
Maximize O2 delivery to the tissues Highest static total compliance Maximum volume change for a given change in pressure Lowest pressure needed to exceed lower inflection point
(LIP or Pflex) on the pressure-volume curve
Select Ventilator GraphicsSelect Ventilator Graphics
Scalar Graphics (time-based)Flow vs. Time
Identify presence of auto-PEEP (expiratory) Identify flow starvation (VCV) Assess / adjust rise time (PCV, PSV) Identify asynchrony
Pressure vs. Time Confirm PIP and PEEP level Visually assess mechanics using PIP-Pplat (~ Raw) and Pplat-PEEP
(~Cstat) Assess sensitivity/trigger response Identify asynchrony
Volume vs. Time Identify leaks Identify asynchrony
X-Y Loop Graphics (loops)Pressure (X-axis) vs. volume (Y-axis)
Assess overall work of breathing Identify overdistension Assess trigger work Adjust PSV levels
Volume (X-axis) vs. flow (Y-axis) Assess bronchodilator response Identify presence of auto-PEEP Identify leaks
Apply Disease-Specific Ventilator Protocols
National Heart, Lung, and Blood Institute (NHLBI) ARDS protocolConsider implementing this protocol for any patient who exhibits an acute onset of respiratory distress not associated with heart failure and has:
A PaO2/FiO2 less than 300 (signifying acute lung injury) Bilateral diffuse infiltrates on X-ray consistent with
pulmonary edema
Initiate and Select Appropriate Settings for High-Frequency Ventilation
You need to be familiar with both infant/child and adult applicationsIndicated for hypoxemic respiratory failure for infants/children/adults who have not responded to more conventional methods of improving oxygenation.Decreasing HFOV frequency tends to lower the PaCO2, while increasing the HFOV frequency tends to raise the PaCO2
Initiate and Modify Weaning ParametersCarefully monitoring the SBT provides the most valid information for deciding whether or not a patient can stay off the ventilator.
NBRC will assess your ability to independently implement a SBT protocol:Straight T-tube breathingCPAPPressure supportPressure support + CPAP
Administer Medications
Aerosolized Drugs:If the patient is receiving several inhaled medications, the recommended order is bronchodilator first, followed by mucolytic, then bronchial hygiene therapy, then steroids, and then the aerosolized antibiotic.Endotracheal InstillationLidocaine, epinephrine, atropine, or naloxone (LEAN)MucolyticsSurfactant
Treating and Preventing HypoxemiaAdminister OxygenIn otherwise normal patients, adjust the flow/FiO2 to the lowest level needed to maintain normal oxygenation (PaO2 of 80 – 100 torr with a saturation ≥ 95%)If you cannot maintain normal oxygenation on less than 50% oxygen, accept a PaO2 ≥ 55-60 torr with a SaO2 (SpO2) ≥ 88%When treating patients with carbon monoxide poisoning, cyanide poisoning, acute pulmonary edema, shock, trauma, or acute myocardial infarction in emergency settings, provide the highest possible FiO2For patients with chronic hypoxemia, aim to keep the PaO2 in the 55-60 torr range to prevent depression of ventilationIn low birth weight or preterm infants at risk for ROP, your goal should be a PaO2 in the 50-70 torr range.
Position Patient to Minimize HypoxemiaSemi-Fowler’s position (head of bed elevated 30 degrees)
To minimize ventilator-associated pneumonia in patients receiving mechanical ventilation
Lateral rotation therapy To prevent or minimize respiratory complications associated
with immobility in bedridden patients“Keeping the good lung down”
To improve the oxygenation in patients with unilateral lung disease
Prone positioning To improve oxygenation in patients with ARDS and refractory
hypoxemia
Prevent Procedure-Associated HypoxemiaAlways monitor the patient’s SpO2 with a pulse oximeter prior to, during, and after any procedure that can cause hypoxemia.
Common Errors to Avoid on the Common Errors to Avoid on the ExamExam
Never use or recommend incentive spirometry for patients who cannot cooperate
Never administer IPPB to a patient with an untreated tension pneumothorax
Never use or recommend noninvasive positive pressure ventilation (NPPV) for patients who do not have control over upper airway function or cannot manage their secretions
Whenever possible, avoid plateau pressures above 30 cmH2O during mechanical ventilation
Do not use or recommend high-frequency oscillation ventilation for patients with obstructive lung disease
More Common Errors to Avoid on More Common Errors to Avoid on the Examthe Exam
Never administer a mucokinetic agent without also providing appropriate bronchial hygiene measures to facilitate secretion removal
Do not use or recommend mast cell stabilizers (cromolyn sodium, nedrocromil) for acute bronchospasm
Never mix Tobramycin (Tobi) with other drugs for inhalation Avoid suctioning (if possible) for 6 hours following
surfactant instillation Never withhold supplemental oxygen from a patient who
needs it
Exam Sure Bets Exam Sure Bets To confirm patient understanding of muscle training,
incentive spirometry, or IPPB, always require a “return demonstration” of the procedure by the patient
To prevent hyperventilation during IPPB, always instruct the patient to avoid forceful exhalation and to breathe slowly.
When initiating mechanical ventilation, always use a high FiO2 (0.60 - 0.90) until an ABG can be obtained.
Except with ARDS patients, when initiating mechanical ventilation, set the initial VT to 8 – 10 ml/kg IBW when targeting volume or set the pressure limit to 20 - 30 cm H2O when targeting pressure
More Exam Sure Bets More Exam Sure Bets To adjust a patient’s PaCO2 / pH during
mechanical ventilation, always change the rate first; change the VT / pressure limit only if rate changes exceed the recommended adult limits (8 – 24 breaths/min) or if you do not achieve the desired results.
Unless contraindicated, always use an oronasal / “full” face mask when initiating NPPV on patients with acute respiratory failure
To avoid esophageal opening / gastric distention, always keep IPAP levels during NPPV below 20 – 25 cm H2O
Whenever a patient’s cardiac output or blood pressure falls when raising the PEEP level, decrease PEEP back to its prior setting
More Exam Sure Bets More Exam Sure Bets Always give the bronchodilator first when ordered
in combination with a mucokinetic or anti-infective agent
To prevent pharyngitis and oral candidiasis with inhaled steroids, always have patients rinse their mouth out after administration
When treating patients with carbon monoxide poisoning, cyanide poisoning, acute pulmonary edema, shock, trauma, or acute myocardial infraction in emergency settings, always provide the highest possible FiO2
Reference:Reference:
Certified Respiratory Therapist Exam Review Guide, Craig Scanlon, Albert Heuer, and Louis SinopoliJones and Bartlett Publishers