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Ventilator Overview and Troubleshooting Settings And Ventilator Overview and Troubleshooting TROUBLESHOOTING ON THE VENT Settings and Management Tip Sheet for Providers High PeaK Pressure Alarm PeaK Pressure (PeaK Inspiratory Pressure, or PIP) • Reflects how hard the ven]lator must work to deliver a breath VARIABLES TO CONSIDER FOR MECHANICAL VENTLIATION MANUEVERS FOR ASSESSING PULMONARY MECHANICS • Normal < 40 cm H2O Func=on of: Mode of Ventilation Controlled: Breath size and Minimum RR set by vent Inspiratory Pause to Assess Pplat Expiratory Pause to Assess autoPEEP o Inspiratory flow (V\), flow paiern Spontaneous: Breath size and RR set by patient o Airway resistance (including pa]ent, ETT, and circuit) Ventilation Variables Plateau pressure (Pplat): Pressure felt by the autoPEEP: Hyperinflation as a result of o Compliance of pa]ent’s respiratory system Respiratory Rate (RR) Adjust to maintain pH > 7.2 lungs, determined by Vt and lung compliance; incomplete emptying before next breath; Risk Monitor for autoPEEP if RR high (esp > 35) Goal Pplat < 30 in ARDS (See ARDS Tip Sheet) of ↓BPs /PEA; See Management of autoPEEP Ini$al approach to high peak pressure alarm… Tidal Volume (VT) Goal 6 or less cc/kg ideal body weight (IBW) for ARDS Step 1: Ask RT to temporarily increase the peak pressure Oxygenation Variables alarm seKng (to ensure paLent receives Full VT) Fraction inhaled Oxygen Ranges 30%-100% Step 2: Check inspiratory pause for Pplat (FiO2) Avoid > 60% for prolonged time, risk of toxicity Positive End Expiratory Optimize PEEP using PEEP tables or driving pressure Is Pplat elevated? Pressure (PEEP) Risk of hypotension with high PEEP Additional Variables Inspiratory Flow Rate (V\) Ven]lator default ~60 LPM NO YES ↑V\ will ↓ Inspiratory me and ↑Peak Pressure (PIP) Flow delivery pattern Ramp / Decelerating Square Wave When to Check: When to Check: ARDS Management (see ARDS Tip Sheet); Expiratory flow on ventilator not 0 at end Increased Resistance Decreased Compliance Airway secretions Abdominal distention Trigger for spontaneous Workup of Elevated Peak Inspiratory of exhalation; h/o COPD/asthma; Workup Flow (standard) or pressure triggered (less sensitive) Pressure (PIP) of ↓BPs of unclear etiology Bronchospasm Pleural effusions breath Kinks in circuit tubing Pneumothorax Patient biting on ETT Pulmonary edema / ARDS Suggested IniGal VenGlator SeHngs Post-IntubaGon Please see dedicated ventilator cards (QR Codes below) for instructions on checking an inspiratory and expiratory hold maneuver for various ventilator brands. AutoPEEP Evaluation Mode: Assist Control-Volume Control (AC-VC) Ventilator SpeciFic Pocket Cards Step 1: Check hemodynamics Tidal Volume (VT) 6 cc/kg (IBW) autoPEEP à hyperinfla]on à decreased preload à ↓BPs à PEA Respiratory Rate (RR) Match pre-intubation RR If ↓BPs due to autoPEEP, disconnect ETT From From vent to ↓hyperinflaLon (requires airborne PPE in COVID+/PUI) FiO2 100% Step 2: Check an expiratory pause and assess expiratory flow at end of expira]on PB 840 PB 980 Maquet Hamilton C1 OR Vent PEEP 10 cm H2O (5 iF hypotensive) Step 3: Improve I:E raIo (↓RR, ↓VT, ↑flow rate, square wave ) Overview of Select Modes of Mechanical Ventilation VENT ADJUSTMENTS WEANING FROM THE VENT MODE OF SET BY PROVIDER DETERMINED BY ADDITIONAL NOTES VENTILATION PATIENT FACTORS Ventilation Oxygenation Ensure you have fixed underlying respiratory problem first Assist-Control o Delivers set VT (with a minimum RR) pH and PaCO2 PaO2 and SpO2 Proceed with a Spontaneous Breathing Trial VT, Minimum RR, PEEP, FiO2, and Peak Inspiratory Pressure (PIP) Volume-Cycled* VC o Fixed VM and low VT can lead to vent - (SBT) and Spontaneous Awakening Trial (SAT) Inspiratory Flow (V\) or and Plateau Pressure (Pplat) dyssynchrony *Preferred Mode AC Inspiratory:Expiratory ra]o (I:E) Actual RR for ARDS o Must monitor for barotrauma (Pplat) PSV 7/5 with FiO2 40% with sedation discontinued Pressure Control ACVC VT, RR PEEP, FiO2 (Consider 5 / 0 for COVID +) PC o Delivers set Pinsp, PEEP (with a min RR) Ventilation - Inspiratory Pressure (Pinsp), PEEP, VT and Inspiratory Flow (V\) o Variable VM with improved comfort and Assess for Failure of SAT/SBT (Assist-Control Minimum RR, FiO2, and I:E (through rise Actual RR vent synchrony P Pressure Cycled) insp time and inspiratory time, TI) o Risk of ↑↑ VT (>6cc/kg) PCV/AC ↑WOB? ↑ HR? ↓ SpO2? ↓ V with ↑ RR? MANDATORY PCV I:E (↓TI, PEEP, FiO2 T ↑rise time), For mandatory breaths: o Delivers set VT (for controlled breaths) Spontaneous For mandatory breaths: Ensure No Other Barriers to ExtubaNon V , RR, PEEP, o Allows for additional spontaneous RR Intermittent T PIP and P breaths (providing pressure support) FiO2, Inspiratory Flow (V\) plat o Risk of ↑↑ VT (>6cc/kg) with Secre]ons < Q3H and normal mental status Mechanical SIMV For spontaneous breaths: SIMV PEEP, FiO2 For spontaneous breaths: spontaneous breaths VT, RR Ventilation VT, RR, I:E, Inspiratory Flow (V\) If AMS: Good cough, gag, withdraws to pain Pinsp, PEEP, and FiO2 o May prolong weaning o WEANING MODALITY Visit the Penn Check out Pressure Support Inspiratory Pressure (Pinsp), o Delivers set Pinsp and PEEP VT, RR, I:E, Inspiratory Flow (V\) PSV Pinsp PEEP, FiO2 COVID-19 Learning the ARDS PSV SPONTANEOUS Ventilation PEEP, and FiO2 o Variable VM and low VT per paRent effort o No minimum RR, requires resp drive Center Site Tip Sheet.
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