Acute Respiratory failure and chronic illness Flashcards
Gluconeogenesis
Gluconeogenesis is the process of generating glucose from sources other than
carbohydrates. Gluconeogenesis occurs mainly in the liver as a way of maintaining
adequate glucose levels in the body when fasting, low carbohydrate diets or starvation
occurs
Glycogenolysis
Glycogenolysis is the breakdown of glycogen to glucose to provide energy for muscle
contraction. It commonly takes place in the cells of the muscle and liver tissues in response
to hormone signals received during the fight-or-flight response
Pneumonia
Pneumonia is categorized as being either community acquired, hospital
acquired or ventilator acquired.
Normal Respiratory Function
Normal Respiratory assessment findings
• Normal ABG’s
• Effective ventilation and gas exchange without support breathing on room air
Respiratory insufficiency
• Abnormal Respiratory assessment findings
• including dyspnea
• Normal ABG’s OR early/minimal changes
• May need supplemental oxygen
• Initially able to support own ventilation, however may need more support as
insufficiency worsens
Respiratory Failure
• Abnormal Respiratory assessment findings rapid shallow breaths, increasing fatigue, difficulty breathing, dyspnea • Abnormal ABG’s • Will need non-invasive or mechanical ventilation or invasive mechanical ventilation and supplemental oxygen
Acute Respiratory Failure
“Respiratory Failure is a condition in which the respiratory system
fails in one or both if its major function”
• Gas exchange (Oxygenation)
• Ventilation (Elimination of CO2
Type I Respiratory Failure
Hypoxemic Respiratory Failure
Gas exchange problem,
PaO2 levels
Type II: Respiratory failure
Hypercapnia
This is a ventilation problem
PaCO2 levels
Mixed both type I and II Respiratory Failure
- Patients can experience both types of respiratory failure at the same time
- Can either be called combined or both types of I and II Respiratory Failure
V/Q Matching
Ventilation and perfusion should be equally matched at the alveolar-capillary membrane level for optimal gas exchange to take place.
Diffusion
- A-C thickness
- Anatomical SA?
- Diffusion coefficient 20:1 (CO2:O2)
- Driving pressure
Hypoxemic Respiratory Failure Patient Presentation
- Initially ↑ RR & ↑ MV
- Later ↑ RR & ↓ Vt
- Decreased compliance
- Breath sounds depends on cause (e.g. crackles, wheezes)
- LOC – depends on degree of hypoxemia
- CVS – depends on degree of hypoxemia & early/late failure
Hypoxemic Respiratory ABGS
initially
Decrease Pa O2
Decreased PaCO2
Alkalosis
Later
Decreased PaO2
Increased PaCO2
Acidotic
Factors that influence ventilation
Internal Compliance. (Stretch and elasticity of the alveoli) External Compliance Airway Resistance Respiratory Muscle Function
Hypercapneic Respiratory Failure Patient Presentation
- ↓ Minute Ventilation
- Use of accessory muscles
- c/o of dyspnea
- Breath sounds depends on cause (crackles, wheeze)
- CNS – headache, changes in LOC
- CVS – flushed, tachycardia, HTN
ABGs Hypercapnic resp failure
high PaCO2
Acidotic
Diagnosis of ARF
• Clinical presentation • Consider History • ABG’s • Chest X-ray • CBC • Cultures (Sputum & Blood) • for gram stain + C&S • CT scan
Treatment of Respiratory Failure
Must treat the Primary cause
Supportive Management of Respiratory Failure (5)
- Promoting adequate gas exchange & ventilation
- Correcting acidosis
- Pharmacological intervention
- Initiating nutritional support
- Preventing further complications
Promoting gas exchange
- Supplemental oxygen
- Positive pressure ventilation
- Both non-invasive & invasive
Promoting ventilation
- Non-Invasive Ventilation
- CPAP or BiPAP
- Invasive ventilation
IPAP improves
Ventilation
EPAP improves
oxygenation
Pharmacology
- Bronchodilators- decrease airway resistance
- Steroids- decrease airway inflammation
- Sedation
- Analgesia
- Paralytics
ARF Positioning
- HOB elevated
* Good Lung down
Strategies to prevent desaturation
- Hyperoxygenation prior to suction
- Spacing out activities and care
- Ensure equipment is secured (ie vent tubing not caught in the bedrails)
PNEUMONIA
• An acute infection of the lung parenchyma that is caused by an infectious agent leading to alveolar consolidation
Typical pneumonia
- Infection from bacteria; multiply extracellularly in the alveoli
- Lobular or bronchopneumonia
- Presents as Consolidation on x-ray
Atypical pneumonia
Viral, fungal and mycoplasminc infections
• Inflammation in the alveolar septums and interstitium of lung
• Presents as Patchy infiltrates on x-ray
Management of pneumonia
Treat the cause with Antibiotics, appropriate antivirals etc.
Support the framework
• Support ventilation & gas exchange
• Maintain hemodynamic stability
• Minimize oxygen and metabolic demand
Ventilator Associated Pneumonia (VAP)
48-72 hours after vent
Common reasons for VAP
The ETT bypasses many of the lungs normal
defenses and creates a fast track for contamination.
Aspiration of gastric contents
Bacteria from the stomach wicking up gastric
tubes.
Micro-aspiration of pooled secretions above cuff.
Risky moves (VAP)
- Nasogastric tube placement
- Bolus enteral feeding
- Gastric over distension
- Stress ulcer treatment
- Supine patient position
- Nasal intubation route
- Instillation of normal saline
- Nonconformance to hand washing protocol
- Indiscriminate use of antibiotics
- Lack of training in VAP prevention
HYPERGLYCEMIA in ARF
This is caused by the body being in a hypermetabolic state
elevated levels of cortisol and other hormonal responses that lead to glycogenolysis and gluconeogenesis.
Elevated blood sugar levels can:
Impair immunologic response to infection
• GI motility
• Increase cardiovascular tone
The goal in the ICU is to maintain control of blood sugar levels in the
high normal range of
6-10
Once a patient becomes chronically critically ill; there are 4 common pathologies
that can occur as a result:
- Chronic stress
- Physiological changes
- Neuroendocrine adaptations
- Malnutrition
Chronic Stress Alters….
- Glucose metabolism and cortisol regulation
- Serum level of toxic interleukins
- Imbalance between pro and anti-inflammatory cytokines
- Homeostasis/Allostasis
Allostasis
A process by which several of the body’s set-points are adjusted or “reset” in
response to an insult/challenge to the system
• e.g. starvation leads the body to change how it breaks down and utilizes fuel
In Chronic Critical Illness:
• Allostasis has been found to occur continuously, causing the body to change
its normally regulated parameters to adjust to the chronic critical illness
• further contributes to chronic stress
Physiological changes in the chronically critically ill
Acquired Muscle dysfunction: myopathies and polyneuropathies
- Profound general weakness
- Reduced deep tendon reflexes
- Alterations in pain, temp and vibratory response
- Numbness and tingling
Preventing Physiological changes in the chronically critically ill
MOBILIZE your patients as early as possible
Work towards early extubation
Limit steroid use
Appropriate and individualized nutrition
Neuroendocrine changes changes in the chronically critically ill Affects two main things:
- Hypothalamus Pituitary Adrenal (HPA) axis
* Autonomic Nervous System (ANS)
Hypothalamus Pituitary Adrenal (HPA) axis
Cortisol
Chronic or prolonged SNS stimulation
exogenous forms (IV etc.) of these drugs can alter the body’s natural ability to produce it’s own- leaving pt unable to respond to stress and restore balance
can also lead to persistent hyperglycemia
parasympathetic nervous system in chronically ill pts
The parasympathetic nervous system tone is reduced in chronically critically ill patients, causing unobstructed activation of toxic cytokines
Four major implications to focus on for chronically critically ill pts
- Mobilization of chronically critically ill patients
- Communication with CCI pts
- Psychological implications for CCI pts
- Support for the family
Mobilization
• Mobilize early • Use caution • Mobilizing is a range of activities • Team effort