Obstructive Lung Disease (Exam IV) Stephen's Cards Flashcards
What is obstructive sleep apnea?
- Recurrent upper airway collapse during sleep
- causes ↓ or complete cessation of airflow
What 3 things will polysomnography recordings show?
- Apnea
- Hypopnea
- Respiratory effort-related arousals
What is the definition of apnea?
- 90% ↓ in amplitude of airflow signal
What are 3 classifications of apnea?
How long do the episodes have to last?
- Obstructive
- Central
- Mixed
- Duration of 10 seconds or more
What is the definition of hypopnea?
- ↓ of 30% or 50% or more in amplitude of nasal presure that last for 90% or more of the breath
- ↓ 4% or more in SpO2
What is the Apnea-hypopnea index (AHI)
Number of apnea and hypopnea events per hour of sleep
What are respiratory effort-related arousals?
- A limitation in the airflow followed by an arousal on the EEG channel. (Flattening of the airflow in a way that does not meet the criteria for apnea or hypopnea)
- Duration of 10 seconds or more
How is sleep apnea or hypopnea diagnosed?
- If AHI ≥ 15
- If AHI ≥ 5 plus S/Sx or associated medical or psychiatric disorder such as HTN CAD CHF insomnia snoring etc
How is Obstructive sleep apnea syndrome (OSAS) diagnosed?
- AHI ≥ 5
- Daytime somnolence ≥ 2 days/week
What are the 3 severity levels of OSA?
- Mild → AHI 5-15
- Moderate → AHI 15-30
- Severe → AHI ≥ 30
What are the 3 direct physiologic mechanisms for Apnea/obstruction?
- Anatomic and functional upper airway obstruction
- ↓ respiratory-related EEG arousal response
- Unstable ventilatory response to chemical stimuli
How are apnea episodes resolved by the body?
- ↑ muscular activity at upper airway and thoracoabdominal respiratory muscles
- EEG arousal
What are some of the neurocognitive consequence of OSA?
- Slower EEG
- Sleep deprivation
- Sleepy in daytime
- ↓ cognition performance
- ↓ quality of life
- ↑ car accidents
What are some of the metabolic consequences of OSA?
- Hypoxic injury
- inflammation
- ↑ SNS activity
- Hormonal changes
- Insulin resistance / DM2
- central obesity
- Metabolic syndrome
What are the most common sites of upper airway obstruction?
Retropalatal and retroglossal regions of the oropharynx
What are some signs that a patient may have an issue with airway obstruction?
- Bony craniofacial abnormalities
- Excess soft tissue
- Acromegaly thyroid enlargement and hypothyroidism
When will the airway collapse?
- When the forces that can collapse airway > than forces the dilate the airway
What are the collapsing forces of the airway?
- intraluminal negative inspiratory pressure
- extraluminal positive pressure
What are the dilating forces on the airway?
- Pharyngeal dilating muscle tone
- Longitudinal traction on upper airway d/t ↑ lung volume
When the patient is ________ airway obstruction is enhanced?
- Supine → supine enhances airway obstruction
Which patient position increases the effect of extraluminal positive pressure against the pharynx?
Supine
Altered neuromuscular control of the airway is related to what 2 things?
- Inflammation
- Denervation
Respiratory related arousal response is related to what 4 things?
- Hypercapnia
- Hypoxia
- Upper airway obstruction
- Work of breathing
What are some clinical symptoms of OSA/apnea?
- Day → dry mouth headache sleepy cognitive impairment
- Night → wake up often snoring choking sensation breathing pauses
What are some comorbidities associated with OSA?
- HTN
- CAD
- MI
- HF
- ESRD
- Graves disease
- DM2
What are some risk factors for OSA?
- elderly
- Obesity
- non-caucasian
- male
- pregnant
- craniofacial abnormalities
- smoking
- narrow airway
What are some treatments for OSA?
- CPAP
- oral appliances
- Eletrical stim → stiimulates hypoglossal nerve (CN12) with every breath
- Weight reduction
- Surg
What are 4 surgeries that might help OSA?
- tonsillectomy
- maxillomandibular advancement
- ubulopalatopharyngoplasty
- adenotonsillectomy
Risk for OSA increases by ___% for every 1 pt increase in ___________ score.
2.5% : Mallampati
During induction what are 4 things we can do to help reduce issues with OSA?
- elevate HOB
- Pre oxygenate
- Know they might be difficult to mask ventilate or intubate
- Minimize or don’t use opioids
What anesthetic type might be preferred for OSA patients?
Regional > GA
What are two mnemonics to help assess OSA?
Snore
Tired
Observed
Pressure
BMI
Age
Neck size
Gender
What is the most common cause for acute URI?
- viral or bacterial nasopharyngitis (95% of cases)
What are 2 possible noninfectious causes of nasopharyngitis?
- Allergic
- Vasomotor
What are some S/Sx of URI?
- nonproductive cough
- sneezing
- rhinorrhea
If a patient has had a URI that is not getting better how does that affect their surgery?
What if it’s getting better?
- Unstable → delay 6 weeks
- Stable → proceed with surg
If the patient has had a recent URI what airway device might be preferred?
- LMA > ETT
What are some adverse respiratory events for a patient that had URI?
- bronchospasm
- airway obstruction
- postintubation croup
- desat
- atelectasis
What can we do to help ↓ risk r/t recent URIs when anesthetizing a patient?
- Hydrate
- ↓ secretions
- limit airway manipulation → URI causes hyperreactive airway
- Nebulized or topical anesthetic to the vocal cords → URI causes hyperreactive airway
- LMA > ETT
What is asthma?
- reversible airway obstruction
- bronchial hyperreactivity
- bronchoconstriction
- chronic airway inflammation
What are some things that ↑ risk for asthma?
- Heriditary
- Family Hx
- mom smoked while pregnant
- Limited childhood exposure to infectious environments
What is status asthmaticus?
Life threatening bronchospasm that persists despite treatment
What are some things that can provoke an asthma attack?
- allergens
- aspirin / β antagonists / NSAIDS
- respiratory viruses
- excercise → typ following exertion than during it
- emotional stress
What is the pathogenesis of asthma?
- chronic inflammation in lower airways activates inflammatory cascade
- Leads to bronchi and airway edema and thickened airways
- Simultaneous areas of inlammation and repair in airways
In a patient with asthma, which inflammatory mediators infiltrate the airway mucosa?
- Eosinophils / neutrophils
- mast cells
- T-cells / B-cells
- Leukotrienes
What are some S/Sx of asthma?
- wheezing
- cough
- dyspnea
- chest tightness
How long can an asthma attack last?
- minutes to hrs
How can we determine if someone has severe asthma?
- prior intubation / ICU admission
- ≥ 2 hospitalizations in a year
- presence of coexisting disease
How is asthma diagnosed?
- S/S
- Airflow obstruction on PFT that is partially reversible with bronchodilators
How is severity of Asthma diagnosed?
- clinical symptoms
- PFTs
- Med usage
What are some PFT changes we would see in an asthmatic?
- FEV1 < 35% of normal
- Possible FRC increase
What are some ABG changes we might see with an asthmatic?
- hypocarbia
- respiratory alkalosis
For mild asthma how will PaO2 and PaCO2 be affected on ABG?
- will be normal
For severe asthma how will PaO2 and PaCO2 be affected on ABG?
- PaO2 < 60 mmHg on RA
- PaCO2 ↑ when the FEV1 < 25%
What changes on CXR will we see with an asthma patient?
- Mild/moderate → normal
- Severe → hyperinflation and vascular congestion of hilum d/t mucous plugging and PHTN
What changes on ECG will be seen in an asthmatic?
- RV strain / irritability
What are 2 goals of treating asthma?
- Prevent / control bronchial inflammation
- Treat bronchospasm
What are 2 SABA meds we talked about?
- Albuterol (Proventil)
- levalbuterol (xopenex)
What are the 7 long term treatments for asthma we discussed in class?
- Inhaled corticosteroids → budesonide fluticasone
- LABA → arformeterol (brovana)
- Combo steriods + LABA → symbicort or advair
- LT modifier → montelukast (singulair)
- Anti- IgE MAB → omalizumab
- Methylxanthines → theophyline aminophylline
- Mast cell stabilizer → Cromolyn
What are some ways to treat status asthmaticus?
- O2
- β2 agonist
- Steroids → hydrocortisone or methylprednisolone
- IV fluid and IV mag sulfate
- broad spectrum ABX
- Ipratropium
- Intubate when PaCO2 > 50 mmHg
When pre-oping an asthma patient what are some things to consider?
- onset age
- triggers
- accessory muscle use wheezing
- stress dose steroids ABX bronchodilators
For an asthmatic what type of anesthesia is preferred?
- regional > GA
What anesthetic meds can be used to suppress hyper-reactive airway?
- fentanyl
- remifentanil
- lidocaine
- prop
- ketamine
What NMBDs should we avoid in an asthma patient?
Atracurium
Any histamine releasing NMBDs.
What is COPD?
- progressive loss of alveolar tissue that is not reversible
What deficiency do COPD patients have?
- α1 - Antitrypsin
What is emphysema?
- destruction of lung parenchyma
What is chronic bronchitis?
- cough and sputum production
What are some risk factors for COPD?
(this is not exhaustive list)
- smoking
- occupational exposure to bad things
- recurrent resp infections
- low birth weight
- asthma
- age
- female
What are some S/Sx of COPD?
- Dyspnea on exertion or at rest
- chronic cough and sputum production
What is a COPD exacerbation?
Acute worsening of airflow obstruction
How is COPD diagnosed?
- FEV1/FVC < 70% normal
- ↑ RV FRC and TLC
- CXR → hyperinflation hyperlucency
What is Bullae associated with?
- emphysema
How do we treat COPD medically?
- Stop smoking
- O2→ if PaO2 < 55mmHg Hct > 55% or if cor pulmonale
- LABA corticosteroids anticholinergics
- Flu / pneumonia vaccines
- Diuretics
What is the goal of O2 therapy for COPD?
- PaO2 > 60 mmHg
How can we treat COPD surgically? How does it help?
- Lung volume reduction surgery
- Help ↑ elastic recoil ↓ hyperinflation ↓ V/Q mismatch
What are some things to consider for COPD patient preop eval?
- smoking Hx
- current meds
- comorbidities
- do they have RV failure
- prior hospitalizations
- optimize before surg
- PFTs/ABGs
- Ventilation
What are some preop risk reductions we can do for COPD patients?
- stop smoking for 6 weeks (8 weeks is even better)
- treat respiratory infections
- treat expiratory airflow obstructions
- lung volume expansion maneuvers