Critical Care II

  1. Mechanical Vents Setting
    Total Volume V1
    Volume of gas delivered to the pt during each ventilator breath.
  2. Oxygen concentration (FIO2)
    • Fraction of inspired oxygen to be delivered to the patient.
    • Room air is 21% or .21
    • FIO2 is set between 21% and 100% (.21-1.0)
    • Adjust to maintain PaO2 greater than 60mmHg and SpO2 greater than 90%.
  3. Positive end-expiratory pressure
    • Positive pressure appplied at the end of expiraton of ventilator breath.
    • Usual setting is 5cm of water.
    • Assists in the prevention of alveolar collapse.
  4. Controlled Mandatory Ventilation
    • Ventilator delivers a preset number of breaths/min of a preset volume.
    • Additional breath CANNOT be triggered by the patient.
    • Used in patients who are paralyzed either by chemical means or by spinal cords injury or neromuscular disease.
    • The are unable to initiated spontaneous breaths.
  5. Assist/Control or Assist/Mandatory Ventilation
    • Ventilator delivers a preset volume at a preset rate andd when patient initiates a breath.
    • Pt can breathe faster than the rate, but not slower.
    • Every breath is supported by the ventilator.
    • Risk for Hyperventilation, if pt breathis spontneously.
    • *Pay close attention to pts breaths
  6. Synchronized intermittent mandatroy ventilation.
    • Delivers a preset volume at a preset rate.
    • Permits spontaneous beathing.
    • The ventilator will synchronize the madatory breaths with the pt's own breath.
    • In between "mandatory breaths" (breaths delivered by the ventilator due to the preset rate), the pt can breathe aat their own rate and volume.
    • *Good for weaning
  7. Pressure support ventilation
    • Fixed amount of pressure augments each breath.
    • When pt initates a breath, a high flow of gas is delivered at the preselected pressure level and this pressure is maintained throughout the inspiration.
    • Pt controls rate, inspiratory time and flow rate.
    • Often used when weaning from the ventilator.
  8. Positive End-Expiratoroy Pressure
    • Positive pressure is applied at the end of exhalagtion in the mechanically vented pt.
    • Restoresfunctional residual capacity by keeping alveoli open at end of expiration and between breaths.
    • Goal: Maintain/improve oxygentation while decreasing risk of oxygen toxicity.
    • If PEEP is used, FiO2 can usually be decreased.
  9. Continuous Positive Airway Pressure
    • Continuous postive airway pressure to prevent upper airway collapse.
    • Pressure is continuous during spontaneous breathing.
    • Frequently used for sleep apnea.
    • Its is usually administered through a tight fitting mask as humidified oxygen or aas a ventilator setting.
    • The presure of flow is constant during both exhaling and inhaling and he level of pressure is determined based on each individual .
  10. Mechanical Venitlation
    • Mechanicl ventilation increases intrathoracic pressure
    • Thoracic vessels are compressed
    • Decreased venous return to the the heart
    • Decreased CO
    • Hypotension.
  11. Mechanical Ventilaiton
    • Berotrauma and Volutrauma
    • Pneumothorax/Tension Pneumothorax
    • Fluids and protens can move inot the alveolar space.
    • Ventilator Associated Pneumonia VAP
    • Pneumonia that occurs 48h or more after ET intubation.
    • ET bypasses upper airway defenses.
    • Aspiration of bacteria from oropharynx is leading cause.
  12. Mechanical Ventilation
    Alveolar Hypoventilation
    • Occurs with inappropriate ventilator setting; leakage of air from ventilator tubing, around ET tube or cuff; lung secreation/obstruction; or low ventilation-perfusion ratio.
    • Respiratory acidosis, cardiac dysrythmias, atelectasis.
  13. Mechanical Ventilation
    Alveolar Hyperventilation
    • Mechanical overventilation or pt hyperventilating.
    • Spontaneous corrects the problem
    • Mechanical vent pt baseline should be the therapeutic goal.
    • Ventilator Dependence
    • Can be difficult to wean pts who require long term ventilation (COPD, neuromuscular disease.
  14. Mechanical Ventilation
    • PPV and PEEP can increase intracranial pressure by impeding venous drainage.
    • Elevate HOB and keep head in alignment.
  15. Mechanical Ventilation
    • Proper positioning to prevent contractures, pressure ulcers, foot drops, and external rotation of hips and legs.
    • Prevent problems associated with immobility(PE, DVT).
  16. Mechanical Ventilation
    • Stress Ulcer and GI bleeding
    • r/t serioius illness, immobility, discomfort of ventilator, decreased CO to gastric mucosa, steroids, pre-existging ucler.
    • Peptic uler prophylaxis.
    • Tube feedings.
    • Constipation
    • Paralytic Ileus
    • Change in thoracic and abd cavity pressure
    • Affects absorption of nutrients.
  17. Mechanical Ventilation
    Psychosocial needs
    • Physical and emotional stress
    • Pt is unable to eat, speak, move, or breathe normally.
    • Pain, fear, anxiety
    • Ordinarry ADLs are extremely difficult.
    • The overwhelming need of ICU pt is to feel safe.
    • Pt will feel safe if communication, reassurance, decision-making (control), Build a truisting relationship.
    • Machine disconnection or malfunction
    • Ensure alarms or ON
    • Have a plan for manual ventilation
  18. Cardiac Output vs. Cardical Index
    • Cardiac Output (CO) = HR X SV
    • Volume of blood pumped b the heart in 1 min
    • 4-8l/min
    • Cardiac Index (CI)
    • Measurement of CO adjusted for body size.
    • More precise measurement
    • Increased: Hyperdynamic states (fever, sepsis)
    • Decreased: Hypovolemia, cardiogenic shock, heart failure.
  19. Preload
    • Amount of muscle fiber stretch at the end of diastole
    • Volume in the ventridcle at the end of diastole
    • PAWP reflexts L ventricle and diastolic pressure = left ventricular preload.
  20. Afterload
    • Pressure or resistance of blood flow out of the ventricle
    • Aterial blood pressure is a major factor affecting afterload
  21. Sytemic Vascular Resistance (SVR)
    • Opposition encountered by left ventricle.
    • Preload, afterload, & contractility determine SVR
    • SVR and aterial BP = comoponents of left bentricular afterload.
  22. Pulmonray Vascular Resistance
    • Opposition encountered by right ventricle
    • PVR and pulmonary artery pressure = components of rt ventricular afterload.
  23. Contractility
    • Force of heart contractiosn
    • Increased contractility means increased SV and increased myocardial O2 requirements.
    • Decreased contractility occurs in a failing heart.
  24. Contractility
    Positive Inotropes
    • Increase or improve contractility
    • Epinephrine and Norepinephrine (Levophed)
    • Isoproterenol (Intropin/Dopamine)
    • Dobutamine
    • Digitalis-like drugs
    • Calcium
    • Milrinone(Primacor)
  25. Contractility
    Negative Inotropes
    • Decrease or diminish contractility
    • Barbiturates
    • Alcohol
    • Calium Channel Blockers
    • B-adrenergic blockers
    • Acidosis
  26. Continuous Atrerial Pressure Monitoring
    • Acute hyper or hypotensioin
    • Acute respiratory failure
    • Shock
    • Neurological Inj
    • Coronary interventional procedures
    • Continuous infusion of vasoactive medication
    • Frequent ABGs
  27. Arterial Line
    Technical Aspects
    • Cannulate a peripheral artery (radial or femoral)
    • Suture cath in place
    • Insertion site MUST be immobilized (prevents dislodging of cath line, Line are not kinked)
    • Types Of Measurements:
    • Systolic, diastolic and mean BP
    • ABGs
  28. Arterial Line
    • Hemorrhage
    • Catheter dislodges or line becomes disconnnected.
    • Prevention (use Leur-Lock connections, Check arterial Waveform, Ensure alarms are on.
    • Infection
    • Inspect for local signs of systemic infection
    • Pressures tubing, flush bag, and transducer should be changed every 96 hour.
  29. Arterial Line
    • circulatory impairment can occure from ( clot, spasm, occulusions of circulation from cath)
    • Neurovascular Impairment
    • If limb is compromised, it will appear pale, cool, and cap refill less 3 sec; pt may feel tingling, pain, or paresthesia.
    • Loss of Limb
    • If neurovascular circulation is not restored to the affected limb, pt may loose limb.
    • Compromised neurovascular status is an emergency.
  30. Art line Interventions
    • Allen Test
    • Assess continous flush bag every 1-4 hrs
    • maintain line patency andlimit thrombus formations
    • ensure bag is inflated to 300mmHg
    • ensure bas has fluid in it
    • ensure system is delivering 3-6ml/hr of fluid 1-2gts/min
    • Nuero checks
    • evaluate neurovascular status distal to the arterial insertion site hourly
  31. Pulmonary Artery Flow Directed Cath
    • Management of acute, complicated cardiac, pulmonary, and intravascular volume problems.
    • Used to measure pulm artery (PAP) pressure and pul ater wedge pressure (PAWP)
    • Increased: heart failure, fluid volume overload, embolism, pulmonary edema, pulmonary HTN
    • Decreased: fluid volume depletion and pulmonary valve stenosis.
  32. Cental Venous Pressure Measurement
    • CVP = measurment of rt ventricular preload
    • Norm = 2-8 mmHg
    • Measured witha PA cath or a central venous cat (CVC)
    • CVP reflects fluid volume problems
    • Increased CVP: Rt ventricular failure, volume overload.
    • Decrease CVP: hypovolemia
  33. Mixed Venous Oxygen Saturation (SvO2)
    • % of Hgb bound to O2 in venous blood
    • Norm = 60-80
    • Procedure = take specimen form distal prot of PA cath, or can be done continuously
    • Reflects pt's ability to balance O2 supply and demand at tissue level.
    • Increased SvO2: Over 80% adequate supply, but decreased consumption
    • Decreased SvO2: Less 60% decreased O2 supply, increased O2 consumption.
    • Decreased CO can be a cause
  34. Measurement of PWAP
    • Measures left ventrical end diastolic presssure or left ventricular pre load
    • NORMAL RANGE 6-12mmHg.
    • Increased: LV failure, cardiac temponade, pulmonary edema, mitral valve regurgitation of stenosis, hypervolemia.
    • Decreased: hypovolemia, vasodilators
  35. Complications of PA Cath
    • Infection & Sepsis
    • Air embolism
    • Pneumothorax
    • Ventricular dysrhythmias
    • PA cath cannot be wedged
    • Pulmonary infarction or PA rupture.
  36. PA Cath
    • Never inflate balloon more than 8-15 sec.
    • Monitor PA pressrue waveforms for evidence of cath occlusions, dislocation, or spontaneous wedging.
    • Cont flush with heparinized saline to reduce risk of thrombus formation.
  37. PA Cath
    • Maintain proper functioning of the monitoring system
    • collect, document and interpret data accurately
    • recognized early clues of complications
    • Baseline data obtained
    • General appearance, LOC, sking color/temp, VS, peripheral pulses, urine output.
Card Set
Critical Care II
CC Lecture