High Risk Aspiration Patients Flashcards
Drawing of a foreign substance, such as gastric contents into the respiratory tract
Aspiration (doesn’t allow lungs to exchange)
Contents involved in aspiration include
secretions, blood, gastric contents, or a foreign body
Aspiration leads to
- aspiration pneumonitis (what we care about)
2. aspiration pneumonia
When material is acidic gastric contents, the patients is at risk for
aspiration pneumonitis
When when is oral secretion containing bacteria, the patient is at risk for
aspiration pneumonia
Aspiration pneumonitis is a type of
acute lung injury
1st phase of aspiration pneumonitis consist of
chemical burning of lung tissue, peaking 1-2 hours after event
2nd phase of aspiration pneumonitis consists of
massive inflammatory response (peaks 4-6 hours after event)
Severity of aspiration pneumonitis is dependent upon
VOLUME AND ACIDITY
What volume/pH is aspiration most severe
> 25 mL
pH < 2.5
Prevalence of aspiration
1/900 to 1/10,000
Aspiration results in what % of airway related deaths
50% (higher than CVCI!)
Why might aspiration be so prevalent and detrimental
lack of adequately identifying risk and modifying anesthetic technique
Aspiration can result in
- dyspnea
- hypoxia
- hypercapnia
- acidosis
- respiratory arrest (causing stress on heart causing dysrhythmias)
Who is at risk for aspiration
- technically everyone
- upper esophageal sphincter issues
- lower esophageal sphincter issues
- bad airway reflexes (trouble cough, swelling, L-spasm)
- too light anesthetic
Why is everyone technically at risk for aspiration
drugs used to produce and maintain GA greatly reduce the body’s natural defense against aspiration
What demographic has decreased airway reflexes
elderly
Why would too light an anesthetic cause aspiration
pain can cause gagging/retching and can increase gastric pressure over LES pressure
In aspiration events, regurgitation occurs how many times as often as active vomiting
3x
What can we do to help aspiration
- identify risk factors
- reduce risk
- execute modified anesthetic techniques
High risk factors for aspiration
- full stomach
- decreased gastric emptying
- esophageal sphincter impairment
What types of patients are likely to have a full stomach
- NON-NPO
- emergency/trauma
- small bowel obstruction
- pregnancy
Highest risk for aspiration
small bowel syndrome
What types of patients are likely to have decreased gastric emptying
- diabetic
- recent trauma
- opioid use
- increased ICP
- pregnancy
What types of patients are likely to have esophageal sphincter impairment
- GERD
- morbid obesity
- hiatal hernia
- pregnancy
- pyloric stenosis
Clear liquids NPO hours
2
Breast milk NPO hours
4
Nonhuman milk NPO hours
6
Light meal NPO hours
6
Regular/hearty meal NPO hours
8
Disorder which slows the movement of food from stomach through pylorus into small intestine
gastroparesis (decreased gastric emptying)
(Decreased gastric emptying) Gastroparesis most often associated with
injury to vagus nerve or idiopathic
What types of people are likely to have gastroparesis (decreased gastric emptying)
- poorly controlled diabetics
- severe pain
- Parkinson’s or MS
When part of the stomach bulges through diaphragm into chest
hiatal hernia (lower sphincter issues)
Thickened pylorus muscle preventing food from traveling from stomach to small intestine
pyloric stenosis (esophageal sphincter impairment)
Cases of esophageal sphincter impairment
hiatal hernia
pyloric stenosis
Demographic commonly associated with pyloric stenosis
pediatrics
How can we reduce risk of aspiration
- decrease gastric volume
- decrease gastric pH
- stop surgery if possible
- regional with MINIMAL sedation
Drugs used to decrease gastric volume
- reglan (metoclopramide)
- erythromycin
- NG tube
Reglan (metoclopramide) method of action and onset
- increases gastric motility/emptying to decrease gastric volume. Also increases pH
- onset 1-3 min
- dopamine antagonist
Erythromycin method of action
antibiotic that promotes gastric emptying
Drugs used to increase gastric pH (decrease acidity)
- H2 blockers
- Proton pump inhibitors (PPIs)
- Antacids
When is reglan contraindicated
Parkinson’s disease treated with L-Dopa or in presence of small bowel obstruction
Common H2 blocker used to increase gastric pH (decrease acidity)
pepcid (famotidine)
- what we usually give
Antacid used to increase gastric pH (decrease acidity)
Sodium citrate (citric acid, bictra; alkalizing salt)
Proton pump inhibitor used to increase gastric pH (decrease acidity)
omeprazole (or other prazoles)
- usually prescribed
H2 antagonists (like blockers) method of action
competitively inhibit action of histamine at H2 receptors on gastric parietal cells, inhibiting gastric acid secretion
- blockers do NOT alter pH of gastric fluid already present in stomach at time of admin
onset of H2 blockers
30 minutes
How can we execute modified anesthetic techniques
- RSI
2. modified RSI (high dose Roc over Sux)
Why do we hold posterior pressure on cricoid cartilage during an RSI
to prevent regurgitated contents from traveling up any higher
Sux dose used in RSI
1-2 mg/kg (on side of 2)
Roc dose used for RSI
0.6-1.2 mg/kg
Why do we not ventilate while waiting for drugs to take effect in RSI?
so we don’t push more air into their stomach?
The airway is never protected (but especially in RSI) until this happens
cuff is inflated
BURP versus cricoid pressure
Cricoid pressure is used to protect the airway from regurgitated contents while BURP is used attempting to gain better view of vocal cords during intubation
BURP stands for
backward
upward
right
pressure
Things you MUST do before extubating an RSI/any concern with stomach
- suction out stomach (OG or NG)
2. awake extubation with return of airway reflexes (get academic with it)
