Pathophys - Test Iii - Aspiration Pneumonitis

Front 1

define pneumonitis

Back 1

inflammation of the lung tissue

Front 2

a type of pneumonitis caused by infection

Back 2

pneumonia

Front 3

both pneumonitis and pneumonia can be caused by

Back 3

aspiration

Front 4

difference in mechanism between aspiration pneumonitis and aspiration pneumonia

Back 4

pneumonitis is when sterile gastric contents are aspirated
pneumonia occurs when colonized oropharyngeal material is aspirated

Front 5

difference in pathophysiology between aspiration pneumonitis and aspiration pneumonia

Back 5

pneumonitis - acute lung injury from acidic and particulate gastric material
pneumonia - acute pulmonary inflammatory response to bacteria and bacterial products

Front 6

difference in bacterial findings between aspiration pneumonitis and aspiration pneumonia

Back 6

pneumonitis - initially sterile with subsequent infection
pneumonia - gram + cocci, gram - rods, and rarely anaerobic bacteria

Front 7

difference in main predisposing factors between aspiration pneumonitis and aspiration pneumonia

Back 7

pneumonitis - depressed level of consciousness
pneumonia - dysphagia and gastric dysmotility

Front 8

difference in age groups affected between aspiration pneumonitis and aspiration pneumonia

Back 8

pneumonitis - any age, but usually young persons
pneumonia - usually elderly persons

Front 9

difference in the aspiration event between aspiration pneumonitis and aspiration pneumonia

Back 9

pneumonitis - usually witnessed
pneumonia - usually not witnessed

Front 10

difference in typical presentation between aspiration pneumonitis and aspiration pneumonia

Back 10

pneumonitis - pt with depressed LOC in whom pulmonary infiltrate and respiratory symptoms develop
pneumonia - institutionalized patient with dysphagia in whom symptoms of pneumonia in a dependent bronchopulmonary segment develop

Front 11

difference in clinical features between aspiration pneumonitis and aspiration pneumonia

Back 11

pneumonitis - range from no symptoms, through non productive cough, tachypnea, bronchospasm, bloody sputum, respiratory distress 2 - 5 hours after aspiration
pneumonia - tachypnea, cough, ,and signs of pneumonia

Front 12

three aspiration syndromes are

Back 12

aspiration of acidic secretions
aspiration of solids
bacterial infection

Front 13

aspiration of acidic secretions results in

Back 13

injury to the lung and an asthma-like syndrome

Front 14

examples of acidic secretion aspiration pneumonitis

Back 14

chemical pneumonitis
mendelson's syndrome

Front 15

aspiration of solids can result in

Back 15

laryngeal or bronchial obstruction

Front 16

definition of Mendelson's syndrome

Back 16

form of acidic aspiration
pH < 2.5
gastric contents of 0.4 ml/kg or more is aspirated

Front 17

two components of pulmonary aspiration are

Back 17

1. gastric contents escape the stomach into the pharynx
2. gastric contents enter the lungs

Front 18

ingestion of aspirate that is highly acidic

Back 18

may result in severe lung injury without an infectious component

Front 19

aspiration usually only occurs when

Back 19

normal protective reflexes (such as coughing, gagging, swallowing) fail

Front 20

why does anesthesia put patients at risk of aspiration

Back 20

normal airway reflexes are depressed

Front 21

three causes of failure of protective airway reflexes are

Back 21

1. depression of the reflexes (anesthesia)
2. alteration in anatomic structures
3. r/t the medical exam or treatment

Front 22

depression of the airway reflexes can occur any time with general anesthesia, but is most likely

Back 22

during induction and emergence

Front 23

why do anesthesia people give bicitra instead of milk of magnesia?

Back 23

non-particulate antacid - so if aspirate less dangerous

Front 24

aspiration of acid solutions cause

Back 24

atelectasis
alveolar damage
loss of surfactant

Front 25

aspiration of particulate results in

Back 25

small airway obstruction
alveolar necrosis
granulomas may form around particulate

Front 26

does pH or volume matter most with aspiration?

Back 26

pH matters more - low volume aspirate with pH less than 1.8 results in severe pneumonitis whereas volumes of 2 ml/kg with a pH greater than 2.5 produces minimal pulmonary damage

Front 27

what drug do we give before surgery to help reduce volume and increase pH

Back 27

pepcid and reglan

Front 28

how long does it take acidic aspirate to cause pulmonary injury

Back 28

12 - 18 seconds

Front 29

how long does it take acidic aspirate to cause extensive atelectasis

Back 29

3 minutes

Front 30

pulmonary aspiration of acids causes

Back 30

loss of mucosal barrier of trachea and major bronchi causing edema and desquamation of epithelium

Front 31

by 1 hour after pulmonary aspiration of acids, pulmonary injury has progressed to

Back 31

bronchial epithelial degeneration
pulmonary edema
hemorrhage

Front 32

as damage from acidic aspiration continues, (pathophysiology)

Back 32

increased pulmonary capillary lead with neutrophil response
fluids and proteins move into alveoli interstitium and reduce surfactant activity
increased airway resistance, decreased pulmonary compliance lead to severe hypoxia
severe hypotension may occur b/c decrease IV volume and impaired venous return b/c high airway pressures

Front 33

compared to aspiration of acidic substances, aspiration of particulates shows

Back 33

earlier and more severe hypoxemia
less severe fluid shifts
greater increase in arterial CO2 tension
greater decrease in arterial pH

Front 34

signs and symptoms of aspiration pneumonitis vary greatly but may include

Back 34

no clinical symptoms
non-productive cough
tachypnea
bronchospasm
laryngospasm
wheezing
hypoxemia
bloody or frothy sputum
respiratory distress
malaise
fever
radiographic changes
pulmonary edema

Front 35

for suspected aspiration cases there is a mandated

Back 35

24-48 hours of post op follow-up to monitor for development of pneumonitis
if no symptoms 6 hours after surgery, pt may go home and follow up on an outpatient basis with specific patient instructions

Front 36

aspiration chest xray will look like

Back 36

white out portion - usually RUL

Front 37

associated comorbidities of aspiration

Back 37

none - can occur in patients with no other disease processes or obvious risk factors at any point of anesthesia care

Front 38

after effects of aspiration

Back 38

range from no obvious adverse effects to death

Front 39

risk factors for aspiration

Back 39

emergency surgery, trauma,full stomach, obstetrics
GI obstruction, hiatal hernia, peptic ulcer disease
difficult airway management, impaired reflexes
seizures, obesity, scleroderma, nausea and vomiting, opiods, cricoid pressure,
cardiac arrest, severe hypotension

Front 40

why does a difficult airway make aspiration more likely

Back 40

more likely to have air in the stomach

Front 41

2/3rds of obvious aspirations

Back 41

produce no signs or symptoms within 2 hours

Front 42

pts with signs or symptoms of aspiration within 2 hours

Back 42

more than half required mechanical ventilation for at least several hours

Front 43

pts that require ventilation for more than 24 hours after aspiration

Back 43

half did not recover

Front 44

overall mortality associated with aspiration

Back 44

5%

Front 45

treatment for aspiration depends on

Back 45

patients signs and symptoms
agent of aspiration
patient airway safety (O2 or intubation?)

Front 46

the most important treatment for aspiration is to

Back 46

maintain pulmonary gas exchange

Front 47

for obvious aspiration

Back 47

clear upper airway with suction
tracheal intubate if no ETT
suction lower airways (see if true aspirate)
supportive treatment

Front 48

key anesthetic implication for aspiration

Back 48

PREVENTION

Front 49

prevention of aspiration relies on drugs that

Back 49

are nonparticulate antacids
promote gastric emptying
increase pH
reduce volume
prokinetic agents (increase lower esophageal sphincter tone)

Front 50

why is bicitra a prophylactic treatment for aspiration?

Back 50

increases gastric pH

Front 51

why are H2 blockers (famotidine and cimetidine) a prophylactic treatment for aspiration?

Back 51

decreases gastric volume
increases gastric pH

Front 52

why is metoclopramide (reglan) a prophylactic treatment for aspiration?

Back 52

increases lower esophageal sphincter tone
decreases gastric volume

Front 53

why are proton pump inhibitors prophylactic treatment for aspiration?

Back 53

decreases gastric volume
increases gastric pH

Front 54

key behavior to prevent aspiration

Back 54

adherence to fasting guidelines

Front 55

minimum fasting time after clear liquids

Back 55

2 hours

Front 56

minimum fasting time after breast milk

Back 56

4 hours

Front 57

minimum fasting time after infant formula

Back 57

6 hours

Front 58

minimum fasting time after non human milk

Back 58

6 hours

Front 59

minimum fasting time after light meal

Back 59

6 hours

Front 60

minimum fasting time after fatty or large meal

Back 60

8 hours

Front 61

why do we have fasting guidelines

Back 61

to reduce risk of aspiration

Front 62

if patient has full stomach,

Back 62

(ideally delay surgery)
or put in an NG or OG and empty stomach and decompress it (Gayle says this is not efficient)

Front 63

proper performance of cricoid pressure

Back 63

2 kg pressure applied when pt awake
4 kg pressure after pt unconscious
do not release pressure until tube is confirmed

Front 64

pts at risk for aspiration - anesthetic considerations

Back 64

cricoid pressure
ensure complete muscle relaxation before laryngoscopy (no cough or gag reflex)
awake extubation

Front 65

Gayles summary of at risk aspiration patient

Back 65

get tube in quick
wait to extubate until awake

Front 66

rapid sequence inductions should be used

Back 66

for patients at risk of or suspected to have a full stomach

Front 67

why does rapid sequence reduce risk of aspiration

Back 67

helps minimize the vulnerable period between LOC and securing of airway

Front 68

cricoid pressure is an integral part of

Back 68

rapid sequence induction

Front 69

another name for cricoid pressure

Back 69

sellicks maneuver

Front 70

check notes for rapid sequence induction example out of Jaffee

Back 70

check notes for rapid sequence induction example out of Jaffee

Front 71

management of patient who has aspirated is difficult because

Back 71

atelectasis, decreased surfactant,
increased airway resistance
decreased pulmonary compliance
hypotension

Front 72

hypotension occurs in patient recently aspirated because

Back 72

impaired venous return due to the high airway pressures

Front 73

treatment of aspiration pneumonitis is

Back 73

supportive -
O2
severe cases may need vent
supportive blood pressure measures if hypotensive

Front 74

do you give steroids to a patient who has aspirated

Back 74

No - no shown benefit but predisposes patient to gram neg. pneumonia

Front 75

do you give antibiotics to a patient with pneumonitis

Back 75

no - just a pneumonia