Critical Care/Respiratory Flashcards
Absolute contraindications for percutaneous tracheostomy placement?
- operator inexperience
- infants
- insertion site infection
- severe/uncontrolled coagulopathy
- unstable cervical spine injury
Hallmark finding in patients with catheter-induced pulmonary artery rupture?
Hemoptysis
Critical first step in management is adequate oxygenation/ventilation with lung isolation of unaffected lung.
Ratio of total dead space (physiologic) to tidal volume?
1/3
Dead space = 2 mL/kg
Relationship of speed of inhalational induction to FRC?
inversely proportional (think of FRC as lung volume diluting volatile anesthetic)
Relationship of speed of inhalational induction to blood:gas coefficient?
inversely proportional
Relationship of speed of inhalational induction to cardiac output?
inversely proportional; affects SOLUBLE volatiles MORE
Relationship of speed of inhalational induction to FA/FI?
proportional
Relationship of speed of inhalational induction to minute ventilation?
proportional
Calculating V/Q ratio?
Ventilation = (tidal volume - dead space) * RR
Q = CO = HR x SV
V/Q
Most common anesthetic complication of an anterior mediastinal mass?
compression of the tracheobronchial tree
Difference between high frequency oscillatory ventilation and high frequency jet ventilation?
HFOV: active inspiration and expiration; mostly used in neonates; very small volumes at 600-1200 per minute
HFJV: active inspiration but passive expiration; tidal volumes smaller than dead space and >100 per minute
How does obesity and pregnancy effect closing capacity?
no effect
Mnemonic for decreased FRC?
PANGOS:
pregnancy
ascites
neonates
GA
obesity
supine position
How does critical illness myopathy present? How to differentiate from critical illness polyneuropathy?
Flaccid quadriparesis and failure to wean from mechanical ventilation in the setting of IV glucocoricoids and ICU.
Deep tendon reflexes and sensation remain NORMAL in CIM vs depressed DTRs in CIP
How does ascites affect lung dynamics?
Mimics restrictive lung disease: all lung volumes are decreased including vital capacity, tidal volumes, FRC, and forced vital capacity. FEV1/FVC is generally UNCHANGED because both values decrease proportionally.
Most important electrolyte to monitor as a donor management goal?
Sodium: goal is < 155
Diagnosis of PHTN requires 3 elements?
- resting PAP > 25
- PCWP < 15
- PVR > 3 Woods units
Flow
Asthma
COPD
Restrictive lung dz
DYNAMIC variable intrathoracic obstruction: positive pressures during expiratory phase pushes obstruction inward while negative pressure pulls obstruction outward with pleura
ex: tracheobroncheal pathology like tracheomalacia, distal tracheal tumors, bronchial tumors, mediastinal mass
DYNAMIC variable extrathoracic obstruction: inspiratory neg pressure drops airway pressure and causes collapse
Ex: VC paralysis, VC constriction, laryngeal tumor, AW burns, glottis strictures, epiglottitis, proximal tracheal tumor
FIXED intrathoracic OR extrathoracic obstru
ex: tracheal stenosis, goiter, foreign body, large AW tumor
Increased PIP by itself usually indicates?
Airway issue: compression, bronchospasm, foreign body, kinked ETT, mucus plug, secretions
Increased PIP plus increased plateau pressure indicates?
extra thoracic or pulmonary problem not related to actual airway:
abdominal insufflation
ascites
intrinsic lung dz
obesity
pulmonary edema
tension PTX
trendelenberg position
The hallmark of restrictive lung disease?
A decrease in total lung capacity less than 80%
FEV1/FVC ratio unchanged
Incompetent inspiratory valve
Exhausted CO2 absorber
partial endotracheal tube obstruction
Phase 2 testing that predicts POOR perioperative outcome post pneumonectomy?
- Inability to ascend at least 2 flights of stairs
- FEV1 < 30% of normal predicted value
- Combined predicted postop FEV1 < 35% and DLCO < 35% of normal predicted value
- Right heart catheter data: mean PAP > 35, mean PCO2 > 45, PO2 < 60,
- and the following right heart catheter data with exercise:
PVR > 190 dynes/sec/cm^5
Maximum VO2 < 15 mL/kg/min
A decrease in arterial oxygen saturation > 2-4%
Phase 1 pneumonectomy testing includes?
ABG analysis and spirometry
CAM ICU is used for?
Assessing delirium not dementia
Components:
Is there a change in mental status or fluctuating course of mental status?
-AND-
Is the patient inattentive or easily disracted?
-PLUS
Is there an altered level of consciousness?
-OR-
Is there disorganized thinking?
Alveolar gas equation formula?
PAO2 = [FiO2 x (Patm - Ph2o)] - (PaCO2/RQ)
RQ = 0.8
Ph2o = 47 mmHg (unless otherwise specified)
qSOFA scoring and criteria?
scoring from 0-3
criteria:
altered mental status GCS < 15
RR > 22
systolic bp < 100
score > 3 indicates a worse prognosis
Risk factors for multi-drug resistant ventilator associated pneumonia:
five or more days of hospitalization
prior IV antibiotic use within 90 days
septic shock at the time of occurrence
acute respiratory distress syndrome or acute renal replacement therapy PRIOR to the occurrence
ABX treatment for multi-drug resistant ventilator associated pneumonia when MRSA prevalence is GREATER than 10% or UNKNOWN
MRSA Coverage:
vanco -OR- linezolid
-PLUS- antipseudomonal beta-lactam based agents:
piper/tazo -OR- cephalosporins (cefepime/ceftazidime) -OR- carbapenems (imipenem/meropenem) -OR- aztreonam
-PLUS- antispeudomonal NON-beta-lactam based agents:
fluroquinolones (floxacins) -OR- aminoglycosides (amikacin/gentamycin/tobramycin) -OR- polymixins (colistin)
Changes in respiratory parameters in elderly patients?
increased:
CC>FRC
RV
Decreased:
IC
TLC
VC
Common derangements in hyperalimentationother than hypophosphatemia?
hypo- or hyperglycemia
acute liver injury with elevated PTT
**patients often require vit K supplementation
Severe causes of decreased phosphate?
Refeeding syndrome Diabetic ketoacidosis (via incr insulin) Large decr in PCO2 (hyperventilation) Diuretics (acetazolamide)
