Critical care - Care of patients on MV and HFNC, ABCDEF CC Bundle Flashcards
Purpose of mechanical ventilator (MV)
- To allow oxygen to be delivered and carbon dioxide to be removed (pts on ETT/trachy/ larygneal edema, compromised conscious level)
- To reduce work of breathing for patients who have impaired lung function (e.g. pneumonia, COPD, stroke)
- To provide respiratory support for patients who have apnoea or respiratory failure (e.g. ARDS)
- To provide ventilation for patient who are under GA
- To protect airway and perform suctioning for patients who are unable to expectorate out their own secretions
(Important) Indications for MV
OVERALL: fully or partially replace work of breathing & gas exchange
- Inadequate ventilation to maintain pH (uncontrolled pH)
- Inadequate oxygenation (PaO2 too low)
- Excessive breathing workload
- Congestive cardiac failure
- Circulatory shock
- Severe neurological dysfunction (e.g. brainstem injury/stroke pt with low GCS)
- Post-operatively (when under GA)
(Important) Goals of MV
- Reduce work of breathing
- Minimise the work of the myocardium
- Restore normal acid/base volume
- Promote gas exchange
- Increase lung volumes
- Reduce atelectasis (collapse of lung)
- Increased level of oxygen delivered
Note: MV does not correct the underlying disorder; it only supports respiratory system
Important components of the MV
- Inhalation tubing: delivers air to pt
- air will be filtered
- humidified via heat moisture exchanger - Exhalation tubing: carries exhaled air away from pt
*note: MV needs to pass the short self test (SST) then can be used, setting of MV is done by RT/ICU intensivist (upper and lower alarm limits have to be set too)
Factors influencing choice of modes
Indication for MV
Level of support
Presence of airflow limitations e.g. COPD/asthma
Presence of air leak e.g. Pneumothorax
Concern for high ICP
Use of paralysis
Doctor’s comfort/familiarity level
Pt’s condition
What is the Continuous Positive Airway Pressure (CPAP) mode?
Usage: For patients who are fully breathing on their own but need help keeping their airways open (e.g., sleep apnea or mild respiratory failure).
How It Works: Provides continuous pressure throughout the breathing cycle to keep the airways open and improve oxygenation, RR, inspiratory flow and tidal volume controlled by pt
Potential complications from MV
- Barotrauma: Damage to lung tissue due to high pressures
- Volutrauma: Overstretching of alveoli due to excessive tidal volumes.
- Atelectrauma: Shearing due to excessive opening and closing of alveoli (due to inadequate PEEP settings).
These above can lead to pneumothorax or subcutaneous emphysema.
- Impaired venous return/cerebral venous return due to increase in intra-thoracic pressure from MV
- For pts with compromised auto-regulation (e.g. TBI, stroke, severe brain edema), MV can cause increased ICP due to increase in intra-thoracic pressure
Nursing care of pts requiring MV (Assessment & Planning)
- Ensure measurement of external length of ETT, lip marking and cuff pressure
- Ensure ETT is taped properly and ventilated on 100% O2 using air viva while awaiting to be connected to MV
- Auscultation of both lungs indicate patent airway and ensure symmetrical expansion of lungs
- Ensure ETT suctioning apparatus is ready at all times
- Ensure NGT placement confirmed (to decompress stomach, prevent gastric aspiration, administer nutrients) with ETT placement with CXR
- Ensure patient is adequately sedated (e.g. IV propofol) to avoid patient-ventilator dyssynchrony
Nursing care of pts requiring MV (Implementation) Pt.1
- Continuous monitoring of patient’s haemodynamic status:
- MAP (via IA line, should be 70-90 mmHg)
- BP, HR, cardiac rhythm
- SpO2, Temperature
- LOC – Sedation Score [e.g. Richmond Agitation-Sedation Scale (RASS)], assess if pt is adequately sedated (prevent over/under sedation) - Monitor series ABG results closely (used to adjust MV setting)
- Troubleshoot alarm triggers
- high pressure alarm (caused by accumulation of secretions, nurse to start NS, do suctioning)
- low pressure alarm (caused by loose connection of MV tubing, ensure all connections are tight)
Nursing care of pts requiring MV (Implementation) Pt.2
- Change Heat Moisture Exchanger (HME) (as per hospital protocol) to prevent bacterial growth and infections
- Refer to PT for chest percussion, suctioning and
follow-up care (ensure pt does not have stasis or accumulation of secretion, help pt regain respiratory function, early weaning) - ETT suctioning every 4 to 8hr
- Prevent decubitus ulcer: 2 hrly turning and use air mattress
- Provide explanation and assurance to patient and family to allay anxiety
- Establish communication channel between nurse and patient –paper and pen, writing board, hand gestures etc
5 Elements of the Ventilator Associated Pneumonia (VAP) bundle
Purpose: Prevention of VAP
- HOB elevation 30deg
- Oral care with chlorhexidine
- Stress ulcer prophylaxis (e.g. Administer PPI)
- Daily sedation assessment and spontaneous breathing trials (in order to wean off MV asap)
- DVT prophylaxis via administration of anticoagulants
Nursing care of pts requiring MV (Evaluation & Documentation)
Evaluate:
- Respiratory status & ABG results
- LOC from sedation vacation to determine readiness for weaning off MV
- Haemodynamic readings
- Oral hygiene and mucosa
Documentation (note any pressure ulcer caused by ETT) - MV settings & observations documentation
Expected patient outcomes from MV
1) able to maintain airway patency and adequate gases exchange and
2) free from complications from the MV (VAP, ventilator induced injury)
What is high flow nasal cannula (HFNC) oxygen therapy?
involves delivering oxygen at high flow (up to 60L/min), heated and humidified controlled concentration via the nasal route to patient who can breathe spontaneously
Which type of patients would require High Flow Nasal Cannula (HFNC)?
- Hypoxemic Respiratory Failure
- Strongly recommended
- (e.g. CAP, viral pneumonia, acute asthma, chronic pul edema) - Following Extubation
- Postoperative HFN for high-risk or obese patients after cardiac or thoracic surgery
