Ventilation & ICU Assessment

• The presentation is about ventilation and ICU (Intensive Care Unit) assessment.
• Eilis Fitzgerald is the Acute Care Practice Tutor at MMUH.

What will be Covered

• Mechanical Ventilation
• Modes of ventilation
• Indications for mechanical ventilation
• Effects of positive pressure on VQ matching
• ICU Assessment
• Comprehensive A-E assessment
• Addressing the Airway
• Evaluating Breathing
• Assessing Cardiovascular System (CVS)
• Evaluating Disability and Neurology
• Exposure and Everything else
• Invasive monitoring

Mechanical Ventilation

• Mechanical ventilation moves gas to and from the lungs using an external device.

Indications for Mechanical Ventilation

• When demand exceeds supply
• Inadequate gas exchange
• Trend of failing ventilation
• Hypoxemia, hypercapnia/Acute Respiratory Failure/Acute on Chronic Respiratory Failure
• Supplemental O2 is not adequate for the patient's needs
• CNS depression causing decreased LOC / drive to breathe
• Decreased neuromuscular function
• Disorders of the musculoskeletal system or pleura
• Disorders of the conducting airways
• Disorders of the exchanging alveoli and pulmonary capillaries

Ways to Deliver Mechanical Ventilation

• Endotracheal tube (ETT)
• Tracheostomy

Mechanical Ventilation Variables

• Volume Control
• Set: Volume
• Volume Delivery: Constant
• Inspiratory Pressure: Variable
• Inspiratory Time: Determined by flow and VT (tidal volume)
• Pressure Control
• Set: Pressure
• Volume Delivery: Variable
• Inspiratory Pressure: Constant
• Inspiratory Time: Set by clinician

Ventilator Modes

• Mandatory ventilation: Most support from the ventilator.
• Synchronized Intermittent Mandatory Ventilation(SIMV): Some support from the patient, some from the ventilator.
• Pressure Support(PS/CPAP): Least support, patient triggers all breaths.

Mandatory Modes - CMV

• The patient has no control over their breathing.
• Rate and volume are set regardless of patient effort.
• Requires total paralysis and sedation to be tolerated.
• Can be pressure control or volume control.
• Respiratory (Resp) rate is set.

Understanding Ventilator Settings

• Mode indicates the type of ventilation being used.
• Pressures, volumes, rate, and oxygen levels are important settings.
• PEEP (Positive End-Expiratory Pressure) is constant pressure and volume delivered on top of PEEP.

SIMV (Synchronized Intermittent Mandatory Ventilation)

• Allows the patient to breathe with support to a set pressure, then cycles into expiration.
• If, however, the patient does not breathe, the ventilator will trigger a breath.
• Settings include SIMV Rate (for mandatory breaths) and Volume control / pressure control (for mandatory settings)
• Settings also include Pressure Support(spontaneous breaths) and PEEP.

Pressure Support

• In Pressure Support the patient must trigger each breath
• The ventilator generates and maintains a pre-selected pressure.
• Settings are Pressure support and PEEP
• It is the last stage of weaning before taking the patient off the ventilator.

Effect of Postive Pressure on V/Q Ratio

• Positive pressure can influence the balance between ventilation (V) and perfusion (Q) in the lungs.
• V/Q ratio describes the relationship between the amount of air reaching the alveoli and the amount of blood flow in the pulmonary capillaries.

ICU assessment

• A total of 220 items were included, 120 of which were deemed essential for a minimum standards of independent clinical practice in Irish critical care units. Fifty six items were considered not essential while consensus was not reached on 44 items.

Database

• First step in assessment
• PC (Presenting Complaint): Why are they here, elective or emergency admission
• HxPC (History of Presenting Complaint): The lead up to the admission
• PMHx (Past Medical History): surgical or medical
• SHx (Social History): living situation, smoking, supports
• Resuscitation status has to be determined
• Baseline: assists with treatment planning and goal setting

Medical Chart

• Medical patient: what is the admission diagnosis?
• Surgical patient: What was the surgical procedure? Elective or emergency?
• Reason for ICU admission should be confirmed
• Check for any post-op instructions
• Were there any eventful peri/post op courses?
• Was there a stable closure of the op site? E.g. sternal closure/abdomen closure

Sequential Organ Failure Assessment (SOFA) Score & Acute Physiology and Chronic Health Evaluation (APACHE) II

• Patients are admitted to determine the level of acuity and mortality risk
• Information from the worst scores from the last 24 hours are taken
• Information used provides the family with a prognosis for clinical trials, or quality assessment
• Identify patients who need ICU admission
• The higher the score the more severe the illness is

Speak to the Nurses

• Asking nurses what they are seeing for the patient is a vital part of your assessment
• How is the patient; are there any updates overnight
• Important events over the past 24 hours
• Is the patient requiring suctioning; coughing/productive?
• Amount, colour viscosity
• Is the patient in Pain?

Observing the Environment

• Look for position in bed
• The mode and method of ventilation
• Drains, lines, wires and attachments
• Evidence of spinal cord management
• Head up positioning in head injuries (30 degree head position)
• Level of consciousness

Patient Overall Impression

• General appearance - distress, anxiety, pain, calm
• Conscious level - awake, alert, attentive, sleeping, drowsy
• Movement quality - speed, co-ordination, required effort

A to E Assessment

• Airway
• Breathing
• Circulation
• Disability
• Exposure/Everything else
• System assessments include the following evaluations
• CNS
• CVS
• Resp
• Renal
• Haem
• MSK

A to E Assessment: Airway

• Is the patient maintaining their own airway?
• Do they require an artificial airway e.g. ETT / tracheostomy?
• What ventilation does the patient require?
• If so, how?

A to E Assessment: Breathing - Respiratory Objective Assessment

• Mode of ventilation
• Settings. Also, what it is set to.
• SpO2/FiO2
• ABG's
• CXR
• Auscultation
• Palpation - crepitus & chest expansion
• Chest drains - are they bubbling, have continuous suction?
• Cough
• Sputum
• Meds - saline nebs, analgesia

Non-Invasive Ventilation

• BIPAP of CPAP
• Interface
• Pressure
• Volumes
• FiO2
• Escalation plan

Mechanical Ventilation

• Airway (ETT or Trachy)
• Level of support (triggering or not); what its is set to
• Pressure
• Volumes
• FiO2
• Rate
• Nitric Oxide

Arterial Blood Gases

• pH should be 7.35 – 7.45
• PaCO2 should be 4.5 – 6kPa
• PaO2 should be 11 - 14kPa
• BE should be -2 - 2
• Bicarb should be 22 – 26
• Respiratory problems - when there are CO2 disturbances
• metabolic problems - when there are HCO3 disturbances
• If PH is < 7.35 = Acidosis (metabolic / respiratory)
• If PH > 7.45 = Alkalosis (metabolic / respiratory)
• Under normal conditions, PaCO2 and HCO3 maintain a stable relationship to allow for normal cellular function

Chest X-Ray:

• Airways should be viewed
• Bones should be reviewed
• Cardiac shadow
• Diaphragms should be evaluated
• Look at the exposure, expansion, equality
• Lung fields should be clear
• Gastric bubble
• Look for collapse, consolidation, pulmonary oedema, pleural effusion, pneumothorax, bullae
• Hyperinflation

Auscultation

• BS may be more harsh in the ventilated patient
• Careful of mistaking sound of air leak at cuff of ETT (Endotracheal tube), bubbling of condensed water in humidifier tubing for wheeze
• Take care with drains leads and wires
• May not always be possible to auscultate all aspects

Chest Drains

• Indications for patients with Air or fluid in the pleural space e.g. pneumothorax, haemothorax, post-op e.g. cardiac surgery
• This provide a method of removing air and fluid substances from the pleural space
• It creates a one-way mechanisms, this will prevent outside air/fluid from entering into the pleural space, accomplished by the sue of an underwater seal
• Should be seeing Swing/Oscillation that is normal - reflects the changes in pleural pressure on breathing (if not on suction)
• it will Gradually lessen and stop as lung re-expands
• If there is bubbling an air-leak should be checked
• Is continuous suction used
• Can they be disconnected for treatment and transfer
• Check if they are leaking
• Will they limit positioning

A to E assessment: Circulation

• HR: Rate, Rhythm - live ECG
• BP: Non-invasive or arterial, supported or unsupported, Mean arterial pressure
• What is/should be the temperature of peripheral temp. Is is < 1 degree of the core temp
• Urine Output
• Fluid balance -(for Kidney Function), Requiring dialysis
• Blood pressure support, Noradrenaline - vasopressor, increases blood pressure, takes blood from peripheries and redirects blood to central systems, as well as Vasopressin, Dobutamine, GTN
• Heart rhythm and rate control, Amiodorone, Digoxin, Beta-Blockers
• Swan Ganz or Pulmonary Artery Catheter used to measure/track changes -Catheter into PA diagnostic purpose, detects heart failure/sepsis Monitor therapy
• Evaluate effect of drugs: useful measure of overall heart function in people who are critically ill
• less blood flow @ peripheries puts patient at of developing necrosis in fingers and toes
• temperature gauge on fingers is standard to monitor the temp @ extremities

Circulation – CVP

Pressure within the right atrium

• Provides info on body volume status/function and right ventricular function Normal: 0-8 mmHg or 3-8 cm H20 < 0 = HYPOvolemia-haemorrhage/dehydrati
• on 8 = HYPERvolemia/right heart failure/PA

A to E Assessment: Disability

• What is the patient Position are they able to reposition themselves?
• Glasgow Coma Scale
• Patients level on the Richmond agitation and sedation scale
• The presence or absence of Delirium
• Medication relating to Sedation and Paralysis why, what and how is how the pt is managed
• Assess pt neurological, can the pt participate (able to show power, display motor function)
• Transfers: supine to side lying, rolling, supine to sit, sit to stand, mobilise and bed to chair

Chelsea Critical Care Physical Assessment Tool

Is: Well validated in ICU setting

• Includes cough and respiratory Function -Used for Daily assessment in MMUH ICU/HDU
• And has Low floor and high ceiling effect

Post intensive care Syndrome (PICS) overview

• Pt experiences cognitive disfunction, decline in physical ability, develop psychological condition like (ex:delirium, anxiety) Socioeconomic and familial distrss
• Can experience Chronic organ dysfunction
• Mechanical ventilation impacts pt through direct effects and side effects
• Sedative drugs
• Neuro muscular Blockade (NMB)
• Enforced bed Rest
• Avoidable deaths post ICU Dc (discharge) prior to Hospital DC (discharge)
• Sub optimal nutrition (41%)