UNIT 1 Respiratory Flashcards

Question

State the equation and normal value for oxygen carrying capacity

Answer 1

CaO2 = SaO2*Hgb*1.34 + PaO2*0.003 normal = 20mL O2/dL

Answer 2

DO2 = CaO2*CO*10 normal = 1000mL O2/min

Answer 3

Left shift (love, increased affinity, decreased offloading to the tissues) - decreased temperature - decreased 2,3-DPG - decreased CO2 - alkalosis/decreased [H+} - abnormal Hgb (HgbF, HgbCO, HgbMet) Right shift (release, decreased affinity, increased offloading to the tissues) - increased temperature - increased 2,3-DPG - increased CO2 - acidosis/increased [H+]

Answer 4

bicarbonate 70% bound to Hgb 23% dissolved in plasma 7% CO2--> HCO3- requires carbonic anhydrase & release of HCO3- from RBC to plasma causes Cl- shift (aka Hamburger shift) --> RBC increases in size

Answer 5

describes O2 carriage | states that increased CO2 & decreased pH causes RBC to release O2

Answer 6

describes CO2 carriage | states that increased O2 causes RBC to release CO2 (occurs in the lungs)

Answer 7

1. increased CO2 production (sepsis, overfeeding, malignant hyperthermia, shivering, seizures, thyroid storm, burns) 2. decreased CO2 elimination (a/w obstruction, increased Vd, increased Vd/Vt, ARDS, COPD, respiratory depression, drug OD, inadequate NMB reversal) 3. rebreathing (incompetent one-way valve, exhausted soda lime)

Answer 8

Medullary Respiratory Centers: 1. Dorsal respiratory center: active during inspiration (respiratory pacemaker) 2. Ventral respiratory center (active during expiration) Pontine Respiratory Centers: 1. Pneumotaxic center (upper pons): inhibits the DRC 2. Apneuristic center (lower pons): stimulates DRC

Answer 9

Central: - located in the medulla - responds to the [H+] in the CSF ([H+] is a function of the PaCO2 of the blood) Peripheral: - located in the carotid bodies: nerves of Hering --> CN IX (glossopharyngeal) - located in the aortic arch (vagus CN X) - respond to decreased O2, increased CO2, and increased H+

Answer 10

Hering-Breuer inflation reflex

Answer 11

minimizes shunt by reducing blood flow through poorly ventilated alveoli a low PAO2 (NOT arterial) is the trigger that activates HPV. - effect begins immediately & takes 15mins for full effect.

Answer 12

Anything that inhibits HPV increases shunt (perfusion w/out ventilation) - halogenated anesthetics >1-1.5MAC - PDE inhibitors - dobutamine - vasodilators IV anesthetics DO NOT inhibit HPV

Answer 13

DLCO is used to assess how well the lung can exchange gas. Normal = 17-25mL/CO/min/mmHg Using Fick's law of diffusion, the DLCO tells us 2 key characteristics about the alveolar-capillary interface: - surface area (decreased w/ emphysema) - thickness (increased by pulmonary fibrosis & edema)

Answer 14

increases SNS tone, sputum production, carboxyhemoglobin concentration, and the risk of infection

Answer 15

Short term (doesn't reduce risk of postop pulmonary complications) - SNS stimulation dissipates after 20-30mins - P50 returns to near normal in 12hrs Intermediate term effects (return of normal pulmonary function requires at least 6 weeks) - improved airway function, mucociliary clearance, sputum production, & pulmonary immune function - CYP450 induction subsides after 6 weeks.

Answer 16

Restrictive = decrease in all lung volumes & FEV1; normal FEV1/FVC ratio, normal FEF25-75 Obstructive = decreased FEV1/FVC & FEF25-75, may have normal other values

Answer 17

normal = upside down ice cream cone obstructive = normal inspiration w/ expiratory obstruction (negative exponential slope) restrictive = shape similar to normal loop but smaller & shifted to the R fixed obstructive = inspiration & expiration are affected.

Answer 18

obstructive = COPD restrictive = pulmonary fibrosis fixed obstruction = tracheal stenosis

Answer 19

``` 100% FiO2 deepen anesthetic (IA, propofol, lidocaine, ketamine) inhaled B2 agonist (albuterol) inhaled anticholinergic (ipratropium) epi 1mcg/kg IV hydrocortisone 2-4mg/kg (takes several hours) aminophylline heliox to reduce airway resistnace ```

Answer 20

alveolar elastase is a naturally occurring enzyme that breaks down pulmonary connective tissue; it's kept in check by alpha-1 antitrypsin (produced in the liver) alpha-1 antitrypsin deficiency --> increased alveolar elastase actions --> panlobular emphysema. Liver transplant is the definitive treatment

Answer 21

prevent barotrauma & reduce air trapping: - low Tv 6-8mL/kg - increased expiratory time - slow inspiratory flow rate to optimize V/Q matching - low PEEP is ok as long as air trapping doesn't occur

Answer 22

characterized by: - impaired lung expansion - decreased lung volumes - normal pulmonary flow rates

Answer 23

Acute: aspiration, negative pressure pulmonary edema Chronic: pulmonary fibrosis, sarcoidosis

Answer 24

Chest wall/mediastinum: kyphoscoliosis, flail chest, NM disorders, mediastinal mass Increased intraabdominal pressure: pregnancy, obesity, ascites

Answer 25

``` trauma emergency surgery pregnancy GI obstruction GERD peptic ulcer disease hiatal hernia ascites difficult airway management cricoid pressure impaired airway reflexes head injury seizures residual NM blockade ```

Answer 26

antacids: sodium citrate, sodium bicarbonate, magnesium trisilicate H2 antagonists: ranitidine, cimetidine, famotidine GI stimulants: metoclopramide PPI: omeprazole, lansoprazole, pantoprazole antiemetics: droperidol, ondansetron routine use of these agents for prophylaxis isn't recommended

Answer 27

chemical aspiration pneumonitis risk factors - gastric pH <2.5 - gastric volume >25mL (0.4mL/kg)

Answer 28

tilt head downward or to the side (first action) - upper airway suction - lower airway suction is only useful for removing particulate matter (not helpful for acidic burn) - secure airway - PEEP to reduce shunt - bronchodilators to reduce wheezing - lidocaine to reduce neutrophil response - steroids probably don't help - Abx only if WBC or fever >48hrs

Answer 29

Consequence of blunt chest trauma w/ multiple rib fractures. The key characteristic is paradoxical movement of the chest wall at the site of the fractures Inspiration: injured ribs move inward & collapse affected region Expiration: injured ribs move outward & affected region doesn't empty TX: epidural catheter or intercostal nerve blocks

Answer 30

mean PAP>25mmHg causes: COPD, L heart disease, connective tissue disorders goals: optimize PVR - increase PaO2 - hypocarbia - alkalosis - decreased intrathoracic pressure (prevent coughing, normal lung volumes, spontaneous ventilation) - drugs: inhaled NO, NTG, phosphodiesterase inhibitors, PGs, CCB, ACEI

Answer 31

reduces O2 carrying capacity of the blood (L shift) CO binds O2 binding site of HgB w/ 200x affinity of O2 --> oxidative phosphorylation & metabolic acidosis

Answer 32

100% FiO2 x6hrs | hyperbaric oxygen if COHgb >25% or if the patient is symptomatic

Answer 33

Absolute: 1. Isolation of one lung to avoid contamination 2. Control of Distribution of ventilation 3. Unilateral bronchopulmonary lavage Relative: 1. surgical exposure 2. pulmonary edema s/p CABG 3. severe hypoxemia r/t lung disease

Answer 34

nondependent lung - moves from flatter region (less compliant) to an area of better compliance (slope) - ventilation is optimal in this lung dependent lung - moves from the slope to the lower, flatter area of the curve (less compliant) - perfusion is best in this lung (gravity) - reduction of alveolar volume contributes to atelectasis net effect: ventilation is better in nondependent lung & perfusion is better in dependent lung. This creates VQ mismatch & increases the risk of hypoxemia during OLV

Answer 35

``` 100% FiO2 confirm DLT position w/ bronchoscope CPAP 10cmH2O to nonventilated lung PEEP 5-10 to ventilated lung alveolar recruitment maneuver clamp pulmonary artery to non-ventilated lung resume two-lung ventilation ```

Answer 36

performed to obtain biopsy of the paratracheal lymph nodes at the level of the carina. Helps to stage the tumor prior to lung resection

Answer 37

hemorrhage & pneumothorax are most common others: - impaired cerebral perfusion - dysrhythmias - air embolism - chylothorax - hoarseness and/or VC paralysis

Answer 38

assesses teh oropharyngeal space, helps quantify the size of the tongue relative to the volume in the mouth I: pillars, uvula, soft palate, hard palate II: uvula, soft palate, hard palate III: soft palate, hard palate IV: hard palate

Answer 39

ability to open the mouth directly affects ability to align the oral, pharyngeal, and laryngeal axes. A small interincisor gap creates a more acute angle b/n the oral & glottic openings, increasing the difficulty of intubation normal = 2-3FB or 4cm

Answer 40

helps estimate the size of the submandibular space w/ neck extended & mouth closed, you can measure the distance from the tip of the thyroid cartilage to the tip of the mentum. DL may be more difficult if the TMD is <6cm (3FB) or greater than 9cm

Answer 41

assesses the function of the TMJ. Pt is asked to sublux the jaw, and the position of the lower incisors is compared to the position of the upper incisors Class I: LI past UI & bite the vermilion of the lip Class II: LI in line w/ UI Class III: LI cannot move past UI (increased risk of difficult intubation)

Answer 42

``` DJD RA ankylosing spondylitis trauma surgical fixation Klippel-Feil Down syndrome ```

Answer 43

helps measure the view we obtain during DVL Grade I: full view Grade II: partial cords, arytenoids Grade III: epiglottis Grade IV: soft tissue

Answer 44

``` BONES beard obese (usually BMI>26) no teeth elderly (age >55) snoring ```

Answer 45

``` small mouth opening narrow palate w/ high arch long upper incisors interincisor distance <3cm MP class 3 or 4 mandibular protrusion class 3 poor compliance of submandibular spce TM distance <6cm or >9cm neck is thick & short poor AO joint mobility ```

Answer 46

``` limited mouth opening upper airway obstruction altered pharyngeal anatomy poor airway compliance increased airway resistance lower airway obstruction ```

Answer 47

``` abnormal neck anatomy obesity short neck limited access to CT membrane laryngeal trauma ```

Answer 48

result of increased vascular permeability that can lead to swelling of the face, tongue and airway: airway obstruction is an extreme concern

Answer 49

ACEI; tx = epi, antihistamines, steroids (just like anaphylaxis) hereditary angioedema (C1 esterase deficiency); tx = C1 esterase concentrate or FFP (i.e. not epi, antihistamines, or steroids)

Answer 50

bacterial infection characterized by a rapidly progressing cellulitis in the floor of the mouth. Inflammation & edema compress the submandibular, submaxillary, and sublingual spaces. the most significant concern is posterior displacement of the tongue resulting in complete, supraglottic airway obstruction

Answer 51

awake nasal intubation or awake trach

Answer 52

``` 2hrs = clear liquids 4hrs = breast milk 6hrs = nonhuman milk, formula, solid food 8hrs = fried or fatty foods ``` ingestion of clear liquids 2hrs before surgery reduces gastric volume & increases gastric pH

Answer 53

Guedel Berman Williams** Ovassapian** **best for fiberoptic intubation

Answer 54

best time to use is when grade 3 view is obtained during DL (grade 2 is the next best time). Likelihood of successful intubation is unacceptably low when a grade 4 view is obtained.

Answer 55

``` cribiform plate injury (LeFort II or III, basilar skull fx, CSF rhinorrhea, raccoon eyes, periorbital edema) coagulopathy previous transsphenoidal hypophysectomy previous Caldwell-Luc procedure nasal fracture ```

Answer 56

ETT <25cmH2O | LMA <60cmH2O

Answer 57

LMA-unique <20cmH2O LMA-proseal <30cmH2O LMA-supreme <30cmH2O

Answer 58

``` 1 = 3.5 1.5 = 4 2 = 4.5 2.5 = 5 3 = 6 4 = 6 5 = 7 ```

Answer 59

``` small mouth opening (minimum 7mm) impaired C-spine mobility short, thick neck Treacher Collins Pierre Robins ```

Answer 60

when the patient is supine, the trachea is anterior to the esophagus. therefore we can look at the quality of the light shining through the neck to determine if the tip is in the trachea or the esophagus - looking for a well-defined circumscribed glow below the thyroid prominence - if it's diffuse, then it's in the esophagus

Answer 61

indicated for lung separation in the following patients - age <8 - requires nasotracheal intubation - have a trach - have a single lumen ETT in place - require intubation after surgery & you want to avoid changing the DLT out

Answer 62

insufflate O2 into the nonventilated lung & suction air from the nonventilated lung to improve surgical exposure cannot: - ventilate - suction blood, pus, or secretions

Answer 63

unstable C-spine | upper airway bleeding (cannot visualize glottis)

Answer 64

awake: - airway reflexes intact - ability to maintain a/w patency - decreased risk of aspiration deep - decreased CV & SNS stimulation - decreased coughing

Answer 65

maintains direct access to the airway following tracheal extubation, thus is helpful during extubation of the difficult airway what else can you do with it? EtCO2 measurement Jet ventilation O2 insufflation

UNIT 1 Respiratory Flashcards

(89 cards)