Critical care lecture one (ALF and ARDS) Flashcards
what are the 3 determinants of pulmonary function
- ventilation
- perfusion
- respiration
ventilation
mechanical movement of airflow to and from the atmosphere and the alveoli
work of breathing
amount of work required to overcome elastic and resistive properties of the lungs
anatomic dead space
the conduting airways (upper airways) that do not partcipate in gas exchange
alveolar dead space
non-perfused alveoli that do not partcipate in gas exchange
physiologic dead space
anatomic and alevolar dead space together
why does respiratory failure occur
- ventilation-perfusion mismatch
what are the four ways that a V/Q mismatch can occur
- Absolute shutn by no ventilation from accumulation of fluid
- V.Q mismacth from mucus secretion
- V/q mismacth from decreased perfusion from emboli
- dead space from no perfusion from obstruction of pulmonary capillary
acute lung failure `
AKA acute respiratory failure that happens suddenly from failure of oxygention versus ventilation
Type 1 ALF
- hypoxemic (low oxygen)
- normocapnic (normal carbonx dioxide)
- pa o2 is less than 60mmhg
- oxygen saturation are less than 80%
Type II ALF
- hypoxemic
- hypercapnic
- usually with patient who have a history of copd and a dignosis of pneumonia
- pa co2 above 45mmhg
- ph is less than 7.35 (acidodic state)
signs and symptoms of ALF I
- dyspnea
- tachypnea
- cyanosis
- acessory muscle use
- decrease spo2
- agitation
what are signs and symptoms of ALF II
- dyspnea
- drowsiness
- bradypnea
- shallow breathing
- decrease minute ventilation
- decrease inhaled volume
what is the nursing interventions/assessments to be done for ALF
- resp assessment
- hemoglobin, blood hases
- chest X-ray
- bronchoscopy, CT scan, sputum cultures
what are non-invasive ways to monitor gas exchange
- pulse oximetry
- capnography - graphic display of carbon dioxide concentration that is exhaled by the patient during breathing
what are the six steps for interpreting an ABG
- are the pa02 and sa02 normal
- is the ph normal
- is the carbon dioxide normal
- is the bicarb. normal
- does the co2 or the bicarb. match the ph
- does the carbon or the bicarb. go to the opposite direction of the ph
mild hypoxemia
pa02 60-75
moderate hypoxemia
pao2 45-59
severe hypoxemia
less than 45
what are contraindications for high flow nasal cannulas
- facial trauma
- airway compromise
- svere shock
- altered mental status
- anythign requiring intubation
non-invasive positive pressure ventilation
- provides ventilatory support without the use of an artifical airway
who is NPPV usually used for
- patient who have type II ALF who do not wish to have invsaive procedures
- people who only need intermittent or support at night
- cardiogenic pulmonary edema with heart failure patients
- oncology patients
what is the criteria for NIPPV to be used
- moderate to severe dyspnea
- tachypnea
- acessory muscle use
- ph less than 7.35 and co2 greater than 45
what are contraindication for NIPPV
- respiratory arrest
- medically unstable such as hypotension or bleeds
- unable to pprtect their own airwat
- excessive scretion
- agitation and uncrooperative
- facial trauma
what is continous positive airway pressure
- NIPPV that delivers one level of pressure
what is bilevle positive airway pressure
- delivers two levels of pressure `
what are various complication of NIPPV
- mask discomfort
- eye irritation
- nasal-related complications
- gastric distentions
- aspiration
- mucous plus
- hypotension
- claustrophobia
what are the physiologic objective of invasive mechanical ventilation
- supporting cardiopulmonary gas exchange
- increasing lung volume
- reducing the work of breathing
what are the clinical objectuves of invasive mechanical ventilation
- reversing hypoxemia and acute respiratory acidosis
- relieving respiratory msucle fatigue
- preventing or reversing alveolar collapse
- permitting sedation and neuromuscular blockade
- decreasing oxygen consumption
- reducing intracranial pressure
- stabilizing the chest wall
what is the nurses role when intubation is being initiated
- prepare of any medications such as sedation, analgesic or paralytcs
- position the patient properly
- connect the patient to ventilator or manually ventilate after placement
what is rapid sequence intubation
- often used in critical care to secure an airway in a patient that is high risk of aspiration
- promotes indcution of unconciousness and skeletal paralysis for intubation in a rapid sequence
what are the 7 P’s of RSI
- preparation - positioning
- pre-oxygenation
- pre-treatment
- paralysis with induction
- protection and positioning
- placement of the tube
- post-care
what should be done with patients who have a difficult to intubate airway
- must have indentity brace;et that identifies they are hard to intubate
- the team should be reminded that this can complicate the procedure
- if their is accidental dislodgement, anesthesiology will need to be present
what are the four principles of mechanical ventilation
- Change from exhalation to inspiration
- inspiration
- change from inspiration to exhalation
- experiation
what are the four variables of mechanical ventilation
- volume
- pressure
- flow
- time
what is PEEP
- positive end expiratory pressure
- normal 3-5cm of water
- it is the amount of volume in the alveoli left after exhalation
- if there is 0 PEEP, leads to alveolar collapse
what is volume limited ventilation
- same volume of air at each breath
- inspiration ends when the set volume is reached
- pressure in the lung will vary
what is pressure limited ventilation
- same inspiratory pressure limit set at each breath
- inspiration ends when set upper pressure limit is reached
- volumes in the lung will vary
mandatory breath
patient is fully sedated and there is breathe delivered every 6 seconds
assisted breaths
if the patient is able to take their own breaths it is a mix of both them and the ventilator
spontaneous breath
the patient is bretahing on their own but they are supported during inspiration
what are the four important ventilator parameter settings
- respiratory rate
- tidal volume
- minute ventilation
- fraction of inspired oxygen
respiratory rate
- number of breaths ventilator delivers per minute
- 6-20 breaths/min
- need to consider the patients condition, ABG and comfort
tidal volume
- volume of gas delivered to the patient with each ventilator breath
- normaly its 6-10ml per kg of body weight
- need to consider patient conditions, abg results, comfort and risk of volutrauma
minute ventilation
- volume of gas inhaled or exhaled from the lungs in one minute
- can be adjusted by increasing or decreasing the tidal volume and resp rate
- normally is between 5-10ml/min
- control of partial pressure of carbon will rely on changes in minute ventilation
fraction of inspired oxygen
- dose of inspired oxygen
- ranges between 21% and 100% for the goals of pao2 being over 60 or the spo2 being over 92%
what is the patient assessment for a ventilated patient
- head to toe with a focus on resp system
- vital signs
- looking at placement of ETT and size
- stabilization of ETT
- cuff inflation
- assessing for vent alarms, comfort of the patient, coughing and agitation
what is the environment check that should be done for ventilated patients
- BVM at bedside with ozygen attached
- PEEP valve
- extra tracheostomy at bedside
- verify suctioning in the room is working
what is the appropriate way to communicate with ventilated patients
- use of close ended questions
- communication boards or white boards
- eye contact and therapeutic touch
what is the nursing management to prevent complications
- management of secretions
- oral hygiene care (q4hrs, collecting secretions above the cuff)
- skin assessment and PI prevention
- mobilization
what are complications when it comes to ventilated patients
- PADIS
- decreased pre-load
- ventilator induced lung injury
- distention, vomiting, hypomotility
- pressure injuries, MARSI, MDRPI
what is the most common cause of death from hospital acquired infection
Ventilator assopciated pneumonia
what are the five componenets of the VAP bundle
- elevate the head of the bed to 45 degree when possible (30 degress if not)
- evaluate if the patient is ready for extubation daily
- use endotrachela tubes with subglottic secretio drainage
- conduct oral acre and decontamination with chlorhexadine
- initiate safe eneteral feeding with 24-48 hours of ICU admission (supports the gut microbiome)
what is the ventilator assessment that should be done qshift
- documentation of vent setting, patient values and alarms
- ventilator cirucit is intact and there is ari inside the tubing
- the tubing are patent and connected
- cuff is inflated
- airway os sexured and tube is in situ
- ABG/VBG monitored as per orders
- CXR reviewed as ordered
what is the patient safety assessment to be done for patients on a ventilator
- maintain a functional manual resuscitation bag connected to oxygen at the bedside
- if ventilator malfunctions, ventilate manually with BVM
- assess for risk of disconnecting from ventilator
what is the criteria for a patient who is ready to be weaned off of the ventilator
- patient is able to initiate inspiratory effort and maintain the effort
- hemodynamically stable (HGB)
- adequate oxygenation
- minimal secretions and they are able to clear their own secretions
what is ARDS
- type of acute diffuse, inflammatory lung injury leading to increased pulmonary vascular permeability, increased lung wieght and loss of aerated lung tissue
clinical hallmarks of ARDS
- hypoxemia
- bilateral radiographic opacities (white-out)
- increased venous admixture
- increased physiological dead space
- decreased lung compliance
what are the three phases of ARDS
- exduative phase - within the first 72 hours of the intial injury
- fibroproliferative phase - begins as disordered healing starts
- resolution phase - occurs over several weeeks
what are direct injury causes that can lead to ARDS
- pneumonia
- gastric aspiration
- near-drowning
- irect sever chest contusion
- inhalation injury
what are treatment adjuvants for ARDS
- steroids
- fluids and diuretics
- pulmonary vasodilators
- hemoglobin tranfusions
- neuromuscualr agents
- PRONE POSITION
- ECMO
what are the early onset clinical manifestations of ARDS
- CXR shows mil alveolar infiltrates
- tachypnea, and dyspnea
- ABG show respiratory alkalosis due to hyperventilation and pao2 shows mild hypoxemia
what type of mechanical ventilation is done for ARDS treatment
- low tidal volumes
- pressure control ventilation
- positive end expiratory pressure
- platuea pressure less than 30cm water
- permissive hypercapnia
- ph 7.30-7.45
- recrutiment maneuvres
- inhaled nitric oxide - vasodilator
what are progressive manifestations of ARDS
- cyanosis
- productive cough
- diffuse crackles and tachycardia
- increasing use of acessory muscle
- ABG that show a pattenr of increasing hypoxemia
- increase pulmonary restriction
what is indirect injury that can leads to ARDS
- sepsis
- severe traumatic injury with shock
- acute prancreatitis
- drug overdose
what types of ARDS has the ighest mortality rate
ARDS due to sepsis
what is the types of ARDS with the lowest mortality rate
ARDS due to trauma and patient who show improvement within the first week of treatment
