Pulmonary Reduced Flashcards Preview

GOAL= minimize risk of post op respiritory failure

1. Caution with pre-medication
   • _{They don’t tolerate respiratory depressant effects of drugs (medulla is “reset” d/t chronic hypercarbia, so these pts are less sensitive to ↑ levels of CO2)}
   • _{Hold opioids until the pt is hooked to monitors and with oxygen on}
2. Ketamine is good for pts who tolerate the CV effects, otherwise propofol
3. Regional is a good choice: Avoid levels > T6
4. Depress airway reflexes/reactivity
   • Lidocaine 1-1.5 mg/kg IV (consider LTA)
   • Opioids -judiciously (fentanyl and analogues)
   • Consiter comorbitities for other agents (Heart failure??)
   • Sevo may be best for bronchodilation (least irritating)​
   • AVOID desfluane/isoflurane - airway irritant​
   • albuterol
5. AVOID histamine realeasers
   • ​Sux, atricurium, mivicurium, D-tubo, morphine, demerol, thopental
6. Use Short acting NMB-
   1. monitor with TOF so you know you are able to reverse
7. ​Neostigmine is ok for reversal, but MUST be given with anticholinergic - glycopyrolate

1. Cautious with N₂O;
   1. Given in high concentration→limits the amount of oxygen delivery 
   2. can cause rupture of bullae from emphysema→ pneumothorax
2. VAs bronchodilate ​but also attentuate Hypoxic Pulmonary Vasoconstriction reflex
3. Increased gradient between PaCO₂ and ETCO₂
   • ​ this is r/t air-trapping & ↑deadspace ventilation

4. Opioids - less useful than VA’s for maintenance phase b/c can be associated w/prolonged depression of ventilation & delayed emergence

5. ​​Humidification

1. No PEEP
2. Large TVs (10-15ml/kg) 

   • _{Large TV’s = ↓ likelihood of turbulent airflow and help maintain optimal VQ matching}

3. low RR (6-10 bpm)
   • _{sufficient time for venous return;} 
4. Humidifier in circuit
5. Consider patient's baseline CO2 and tolerate hypercarbia based on it
   • _{are they a blue bloater or pink puffer?}
6. Monitor for air trapping
   • ​_{monitor for intrinsic PEEP or dynamic hyperinflation r/t air-trapping (expiratory volume never reaches baseline again, so next breath starts out at a higher baseline volume)}

Postoperative ventalitory status is the Priority issue

1. May need to stay intubated/ventilated for prolonged period (they are susceptible to acute respiratory failure during post-op pd (d/t atelectasis, hypercapnia, hypoxemia, retention of secretions, bronchospasm​)
   • _{esp. after abdominal/thoracic surgeries →but the goal is to get them extubated as soon as possible, they wil do better!}
   • _{Education →Post op ventilation is NOT a complication, but rather an expected result}
2. Adjust vent based on blood gasses
3. Adequate pain control 
   • _{allows for pain free breathing and improved coughing & to avoid splinting → reduced atelectasis risk} 

Normal compliance = 100-200ml/cmH_​2O

1. Increased fibrous tissue

   • long-standing COPD, sarcoidosis, bleomycin toxicity

2. Alveolar edema
   • sepsis, re-expansion pulm edema, negative pressure pulm edema
3. Low lung volumes
   • atalectasis
4. Increased pulm venous pressure
   • pulm HTN secondary to chronic Hypoxic Pulmonary Vasoconstriction

1. Acute intrinsic (pulm edema, ARDS, aspiration pneumonitis)
2. Chronic intrinsic (pulm fibrosis, sarcoidosis)
3. Chronic extrinsic (chest wall/ab/neuromusc diseases, obesity, kyphosis)
4. Disorders of pleura/mediastinum (tumors, pneumothorax, pleural effusions)

Acute Intrinsic restrictive disorder

Occurs after rapid evacuation of > 1L from pneumothorax/effusion that's > 24 hours old, due to enhanced capillary membrane permeability 

1. Treament:
   1. O₂
   2. PEEP
   3. no diuretics unless volume overload is primary issue

Acute Intrinsic restrictive disorder 

Occurs minutes to 2-3 hours after acute upper airway obstruction (in a spontaneously breating patient)

1. Highly negative intrapleural pressure causes: 
   • decreased interstitial hydrostatic pressure
   • increased venous return
   • increased LV afterload
   • incerased SNS outflow→HTN and displacement of blood volume
   • Acute pulmonary edema
2. Most often caused by:
   • post-extubation laryngospasm
   • attempting to breath against closed airway- muscle guys
   • Obstructve sleep apnea, hiccups, epiglotitis, tumors
3. self-limiting to 12-24 hour duration
4. Treatment:  
   • O2
   • airway monitoring/maintinence (C-Pap if needed)
   • mechanical ventilation + PEEP if needed

Acute Intrinsic restrictive disorder

Gastric Acid aspirate is rapidly distributed through the lungs it destroys surfactant producing cells and injures lung epithelium

1. Results in capilary permability/atelectesis
2. s/s:
   • arterial hypoxemia (decreased sats)
   • Tachypnea
   • Bronchospasm
   • Pulmonary vascular constriction can causel pulmonary HTN
   • X-ray shows changes 6-12 hours later 
3. Treatment: 
   • Increase FiO2
   • PEEP
   • B2 agonists (albuterol) bronchodilation
   • Bronchoscopy if suspect solid material
   • generally abx and steroid use is not used

Chronic Intrinsic restrictive disorder

Systemic granulomas disorder that leads to pulmonary fibrosis leading to cor pulmonale and pulmonary hypertension

• Laryngeal sarcoid = Decrease diameter of airway (smaller tube and difficult  airway/intubation)
• Myocardial sarcoid = heartblocks, dysrhythmias, restrictive cardiomyopathy → cardiac involvement
• Liver, spleen, unilateral optic and facial nerves palsey

1. Often present w/ dyspnea, cough & rapid shallow breathing
2. Cor pulmonale and pulm HTN are likely
3. Decreased alveolar diffusion capacity
4. Often haveng a mediasinoscopy →lymph node biopsy
5. Often times on corticosteroids→STRESS DOSE!
6. Check electrolytes; check for hyperclacemia r/t metabolism of granulomas

1. Chest wall disorders
   • decreased lung voume corespond with increased airway resistence
2. Neuromuscular disorders -
   • Inefective cough/clearance of secretions
   • prone to infection/pneumonia  
   • high risk for aspiration d/t ineffective swallowing.
3. Mediastinal tumors
   • ​​can compress the pumonary artery, myocardium or SVC
   • can occulde airway if given a muscle relaxant

1. Acute dyspnea
2. Ipsilateral chest pain
3. Decreased PaO2
4. increased PaCO2
5. Hypotension
6. Tachycardia
7. Uneven/decreased chest wall movement
8. Hyperresonant percussion
9. Decreased or absent breath sounds

1. AVOID > T10 level =  loss of accessory muscles
   • vital esp in spont breathing patients
2. Good to note they don't tolerate sedation well so regional may be benificial for post op pain control 

1. Pre-meds: Titrate pre-meds carefully to avoid respiratory depression (lose accessory muscle function easily)
   • they need high minute vent to compensate for low volumes
2. Pre-oxygenation critical d/t reduced FRC & decreased safe apnea time
3. Will have a shorter apnea time - work efficiently
4. Use nitrous with caution - risk for barotrauma!!
5. May need etomidate if CV comorbidities
6. Use short actinng NMB

1. AVOID nirtrous due to risk of barotrauma!!
2. Volitile agents have accelerted uptake 
   • decreased FRC and increased RR
3. Mechanical ventilation:
   1.  USE: ETT (LMA not a good choice→loss of accessory mucsle and inability to maintain oxygenation) 
   2. Decreased Tidal Volume (4-8 mL/kg)
   3. Increased RR (14-18 breaths per minute)
   4. Expecct higher peak airway pressures but the goal is to keep 2O 
   5. Consider the risk for barotrauma → high risk!!!
   6. Avoid excessive FiO₂

Assessment:

1. What is their exercise tolerance & baseline dyspnea
2. Can use PFTs, flow volume loops & ABGs to grade the severity of the restrictive disease
3. Increased risk: 
   • Decreased Vital Capacity (70 ml/kg is normal)
   • Resting Hypercarbia

Optimization (5 things)

1. Treat any active pulmonary infection
2. Improve sputum clearence
3. Treat cardiac dysfunction
4. IS- to improve respiratory muscle strength & stamina
5. Smoking cessation

Respiratory Criteria for extubation

1. PaO₂ > 60 mmHg
2. SaO₂ > 90%
3. PaCO₂   mmHg
4. Respiratory Rate breaths/minute
5. Tidal Volume > 300 mL (6 ml/kg)
6. Vital capacity > 10-15 mL/kg (or SV of 2-3 ml/kg)
7. Full reversal of NMB
8. Return of laryngeal reflexes
9. Adequate LOC & muscle strenght (head lift >5 sec)

Have a lower threshold for: 

1. Post -op mechanical ventilation
2. Monitoring in a postoperative bed & maybe a slow wean in ICU

High Risk of Post-op respiratory failure!!  _{d/t ↓ lung volumes & impaired cough}

1. Transport to PACU with supplimental O₂
2. treat pain adequately, but avoid respiratory depression
   • ​​regional comes in handy
   • consiter the surgical site - thoracis surgery - you don't want splinting but try to avoid atelectasis

​remember, pts present with:

1. ​decreasde lung volumes and impaired cough 
2. rapid shallow breathing pattern
3. abdominal impingement of diaphram

1. If the surgery is elective →CANCEL IT!
2. If emergency surgery indicated
   1. Use diuretics for fluid overload
   2. vasodilators and inotropes for cardiac failure
   3. Consider drainage of pleural effusions/ascites pre-op
   4. May need an ICU vent -(for the propper settings)
   5. AGGRESSIVE hemodynamic monitoring
      • art line, CVP, +/- PA catheter

BOTH Asthma and COPD

• Inhaled ß-agonists (albuterol) - bronchodilation
• Inhaled and systemic corticosteroids - decrease inflammation
• Mast cell Stabilizers (Cromolyn) - decrease histamine release
• Phosphodiesterase inhibitors - bronchodilation via increased cAMP (Thophyline/methyxanthines)

COPD - parasympatholytics - (atropine inhalers)

ASTHMA - leukotriene inhibitors (singulair)