Equipment, Resp, Procedures, Misc Flashcards
1
Q
Peak pressure goal
A
<40
2
Q
inspiratory flow
A
flow that must overcome pulmonary recoil and resistance in airway
3
Q
Minute ventilation is RR x TV and encompasses….
A
alveolar ventilation and dead
space ventilation
4
Q
A rise in MV due to hypercarbia first occurs by increasing Vt and RR, but this happens after….
A
respiratory drive has become significantly elevated above resting ventilation
5
Q
Dead space & what increases it
A
unperfused or poorly perfused alveoli
Pulmonary emboli of air, thrombus, or cellular debris
6
Q
Types of dead space
The volume of lung involved in dead space ventilation includes three components…
A
- anatomic: nose, pharynx, and conducting airways
- alveolar: where alveolar blood flow is minimal (e.g., low CO, VAE)
- instrumental: masks, ventilator components distal to the Y-piece (ETT, connectors, heat & moisture exchange)
7
Q
Recruitment maneuvers
A
opens atelectatic areas
35-40 sustained pressure for 30- 40 ses
or
increase PEEP in increments of 5 x 5 breaths until PEEP reaches 20 plateauing at a pressure of 40
8
Q
one lung ventilation (OLV)
-dependent lung
A
- Vt that gives airway pressure <25
- rate to maintain a PaCO2 of 32-38
9
Q
Functional Airway Divisions
A
10
Q
Breathing
vs
Ventilation
vs
Respiration
A
- Breathing- inspiring & exhaling requiring energy (limited by energy reserves)
- Ventilation- moving gas in & out of the lungs
- Respiration- energy released from organic molecules, energy dependent on the movement of gas molecules of co2 and o2
11
Q
Vital Capacity (VC)
NR
A
60 ml/kg varies about 20%
12
Q
deep breathing and effective coughing is a reflection of
A
vital capacity
13
Q
The capacities
A
- Inspiratory Capacity (IC)- the largest volume of gas that can be inspired at rest
- Functional Residual Capacity (FRC) – remaining volume after normal exhalation
- Residual Volume (RV)- air cannot be expelled after forced expiration
- Forced Vital Capacity (FVC)- volume exhaled as forcefully as possible
14
Q
Forced Vital Capacity (FVC)
importance
A
volume exhaled as forcefully as possible
<15ml/kg a/w Pulmonary complications
15
Q
Normal Values of lung parameters
A
16
Q
O2 analyzer is the….
A
only monitor that detects problems downstream from the flow control valves
17
Q
Paramagnetic
A
self-calibrating, more costly with fast response time
can detect insp & exp O2
18
Q
All analyzers must have …
A
low-level alarms, which are active while the machine is on
19
Q
Galvanic Cell (fuel cell) is used on the ___ limb
A
insp
20
Q
Qualities of O2 as a gas
A
nonpolar gas
paramagnetic
When placed in a magnetic field, O2 will expand contracting when the magnet is turned off.
By switching the field on and off and comparing the change in volume (or pressure or flow) the amount of oxygen can be measured
21
Q
Spirometry and pressure measurements
The most common problems detected
&
their cause
A
low peak inspiratory pressure: ventilator or circuit disconnect
high peak inspiratory pressure: airway obstruction
22
Q
Treatment of laryngospasm
A
- Remove offending stimulus (secretions)
- 100% O2 + CPAP
- Deepen
- Larson
- rapid-acting NMB (succinylcholine)
23
Q
Larson’s maneuver
A
apply painful inward and anterior pressure at the “Larsons point” bilaterally while performing a jaw thrust
24
Q
Laryngeal notch
A
- located behind the lobule of the pinna of each ear
- bounded anteriorly by the ascending ramus of the mandible adajacent to the condyle
- posteriorly by the mastoid process of the temporal bone
- cephalad by the base of the skull
25
noncardiogenic (negative pressure) pulmonary edema
spontaneous ventilation against closed vocal cords
26
in a healthy patient desaturation may take ___ if properly pre-oxygenated
8 minutes
27
Preoxygenation
Time-sparing method
4 vital capacity breaths of 100% O2 over 30 seconds
or
8 deep breaths in 60 second period
28
Normal FRC in 70kg adult
2,400 ml
29
importance of FRC
* key role in determining oxygen reserves
* propensity to atelectasis
* effects on MV
30
Reduced FRC (due to decreased ERV) can result in
lung volumes below closing capacity in the
course of normal tidal ventilation
1. small airway closure
2. VQ mismatch
3. right-to-left shunting
4. arterial hypoxemia
31
peripheral
vs
central
chemoreceptors
peripheral: carotid & aortic bodies
Respond to changes in PaO2, PaCo2, pH, and arterial perfusion pressure
central: anterolateral surface of the medulla
respond primarily to changes in CSF [H+]
32
Hypoxic drive
-is mediated by...
-is depressed by...
-is abolished by...
mediated by peripheral chemoreceptors in the carotid bodies
markedly depressed by nitrous
abolished by Antidopaminergic drugs—phenothiazines-, most general anesthetics, and bilateral carotid surgery (periph response to hypoOx)
33
Peripheral chemoreceptors interact with central respiratory centers via ___ and respond by....
Glossopharyngeal nerves
producing reflex increases in alveolar ventilation in response to **reductions in PaO2**
34
Peripheral chemoreceptors are stimulated by
cyanide, doxapram and large doses of nicotine.
35
Chemoreceptor activity does not appreciably increase until
PaO2 decreases below 50
36
How do Central chemoreceptors detect and respond?
Increases in PaCO2 elevate CSF [H+]
activate the chemoreceptors
(so decreases in CSF [H+] d/t reduced PaCO2 *reduce alveolar ventilation and elevate PaCO2*)
37
Only ___ chemoreceptor activity is depressed by hypoxia
CENTRAL
38
Bain circuit
- modified mapleson D
- FGF must be 2.5x the mV to prevent rebreathing
- con: unrecognized disconnect/kink of inner FG hose = hypercapnia or increase respiratory resistance
39
Components of the circle breathing system (7)
1. FG inflow
2. unidirectional valves
3. corrug. tube
4. Y piece
5. APL
6. Resevior bag
7. CO2 absorbent
40
Circle system
3 classifications
* Semi-open: no rebreathing and requires very high FGF
* Semi-closed: some rebreathing of exhaled gases
* Closed: FGF = uptake/consumption; rebreathe gases after CO2 absorption; overflow (APL) valve or ventilator pressure relief valve remains closed
41
Oxygen sensor location
&
rationale for its location
located distal to the CGO, as proximal to the patient as possible
to be able to determine the concentration of oxygen moving toward the patient
## Footnote
only thing to detect a hypoxic mixture!
42
Capnography
Continuous assessment of (3)
metabolism, circulation, and ventilation
43
etco2-PaCO2 gradient in the healthy supine patient
~5 mmHg
44
where CO2 is measured
Point D
35-40 mmHg
45
A & B angle NR
and interpretation
Alpha: 100-110 degrees
increased alpha → expiratory airflow obstruction, COPD, bronchospasm or kinked ETT
Beta: 90 degrees
increased beta → rebreathing, exhausted co2 abs.
46
Whats going on?
Wyd?
asthma, COPD
reduce rate, increase Vt, no PEEP
47
whats happening
leak in sampling line
48
DISS vs PISS
fxn
DISS = hose
PISS = cylinder
"Deez hoes!"
49
DISS colors
* Green: Oxygen
* Yellow: Air
* White: Vacuum
* Blue: Nitrous
50
PISS values
51
Tank PSI & volumes
Oxygen tank: PSI 1900 660 L
Nitrous Oxide: PSI 745 1590 L
52
Low pressure circuit (LPC) leak test
checks from flow control valves to common gas outlet
(Portion of the machine that is downstream from all safety devices **except the O2 analyzer**)
53
Components in this area are most susceptible to breaking & leaks
low pressure system
54
Why do we care about leaks in the low pressure system? Where are they common?
can cause hypoxia & awareness
* interface between glass flow tubes and its manifold
* O-ring junctions between vaporizer and its manifold
* Loose filler caps on vaporizers
55
Methods of checking for leaks
in Low pressure system
* O2 flush test
* Common gas outlet occlusion test
* Positive pressure leak test
* Negative pressure leak test
56
How to do the LPC leak test depending on if there's an outlet check valve
* no outlet check valve: positive-pressure leak test (squeeze bulb)
* with outlet check valve: negative pressure leak test (suction bulb)
57
Superior Laryngeal Nerve
damage will cause...
* External (M) = hoarse
* Internal (S) = difficulty phonating
58
Recurrent Laryngeal Nerve
damage will cause...
unilateral - hoarseness
Bilateral - stridor/resp distress (acute) or aphonia (chronic)
59
Blood supply to larynx is from
superior/inferior thyroid artery
60
Thyroidectomy
how to prepare the pt
Primary goal: euthyroid before surgery (min 10-14 days of meds, ideally 8 weeks before surgery)
61
Meds related to thyroidectomy
* Propylthiouracil (PTU): inhibits conversion of T4 to T3
* Methimazole: inhibit organification of iodide & block T3/T4 synthesis
* Beta-blockers: decrease SNS activity
* Steroids: continued (may need stress dose day of)
62
T/F:
For a Thyroidectomy, anticipate a difficult airway and the need for an airway block.
False
yes difficult airway but avoid airway blocks
63
Thyroidectomy
Intraop Considerations
- deep anesthesia to avoid SNS stim
- NEO instead of ephedrine (avoid inc. HR)
- esmolol for tachycardia
- NIMS ETT
- bed 180
- shoulder roll for neck extension
- No NMB, TIVA, or TIVA + 1/2 MAC gas
64
Bilateral injury to RLN
reintubate
65
thyroidectomy
Complications/Risks
66
Thyroid Storm
S/S
acute exacerbation hyperthyroid)
* Hyperthermia
* Tachycardia, HTN
* Myocardial ischemia / CHF
* Agitation, Confusion
67
Thyroid Storm Tx
Goal: stop hypermetab. & manage symptoms
* CV/vent support
* Cooling
* HR < 100
* high FiO2
* BB (esmolol gtt, propranolol),
* **hydrocortisone (50-100 mg q6)**
* **antithyroid meds (PTU 200-400)**
* **sodium iodide (250 mg IV q6)**
68
Thyroidectomy can lead to...
hypoparathyroidism
from accidental removal of all 4 parathyroid glands during surgery
69
First sign of hypocalcemia tetany
laryngeal stridor & laryngospasm
70
In thyroid storm, avoid these meds
aspirin & lasix
increase thyroid hormone levels
71
Anti-psychotic drugs:
Phenothiazines
Aliphatic: major tranquilizers
Chlorpromazine (prototype) D2 blockade
Piperidine: relatively less potent (Thioridazine)
Piperazine: relatively more potent, more SEs (Fluphenazine)
72
Anti-psychotic drugs:
Thioxanthenes
Thiothixene (navane)
73
Anti-psychotics:
Butyrophenones
some of the most potent antipsychotics
Droperidol (inapsine) & Haloperidol (haldol)
74
Anti-psychotic drugs
endocrine effects
(dopamine antagonists) → increased estrogen
○ Females: amenorrhea, false + preg test, incr libido ○ Males: decr libido, gynecomastia
75
# Antipsychotics
High dose phenothiazines
* Ortho hypoTN, Tachycardia, Reduced MAP, PVR, SV
* Mostly d/t ANS SEs
* ECG: Q-T prolongation, ST segment & T changes
76
Early vs late signs
antipsychotics
early: Parkinsons & akasthisia
late: TD
77
choreoathetoid movements
TD
78
Parkinson's & akasthisia are both treated with __ agents
antimuscarinics
## Footnote
Parkinsons = dopamine blockage
79
Most significant adverse side effect of antipsychotic drug treatment
TD
80
Tardive dyskinesia
Tx
* stop/reduce antipsychotics
* stop central anticholinergics (Parkinson drugs/TCAs)
## Footnote
If no therapeutic response: high-dose diazepam (30-40 mg per day)
81
Neuroleptic anesthesia
droperidol (butyrophenone) + fentanyl
82
Neuroleptic Malignant Syndrome
Seen in pts ...
sensitive to antipsychotic extrapyramidal effects
83
NMS causes muscle damage which is seen as in increase in...
CK isozymes
84
T/F:
NMS can be treated with antipsychotics.
False!
Anti-Parkinsonian drugs
85
compensation in this acid/base disorder is not as effective
resp. acidosis
(kidneys need time to conserve bicarb & eliminate H)
86
Which fluids should be given based on each acid/balance disorder
* resp acid = lactate
* resp. alk. = chloride
* metab acid = bicarb & lactate
* metab alk = NaCl, K, Cl
## Footnote
lactate converts to bicarb in liver
Cl replaces bicarb
87
Respiratory Acidosis vs Alkalosis
S/S
acidosis: Headache, restless, blurred vision, apprehension, lethargy, muscle twitching,
tremors, convulsions, coma
alkalosis: Dizziness, confusion, paresthesias, convulsions, coma w/ signs of **hypocalcemia**
88
Early salicylate intoxication can lead to which acid/base imbalance?
resp alkalosis
89
High altitudes & Hypermetabolic states (fever, anemia, thyrotoxicosis) can lead to which acid/base imbalance?
resp alk.
90
Metabolic Acidosis
causes
* Lactic acidosis
* Renal failure
* DKA
* Diarrhea
* Starvation
91
Metab acidosis
S/S
Headache, lethargy, kussmal respirations
92
kussmal respirations can be seen in which acid/base imbalance?
metab. acidosis
93
Anion gap
* distinguish different types of **metabolic acidosis**
* Normal: 10-12 mEq/L
94
Metabolic Alkalosis
values
HCO3 > 26
pH > 7.45
95
Metabolic Alkalosis
causes
* Prolonged vomiting
* Gastric suctioning
* **Hyperaldosteronism with hypokalemia**
* **Diuretics**
* Excessive bicarbonate intake
95
96
SEP monitors...
ascending tracts (posterior spinal cord) alert to impending damage to posterior spinal cord
97
SEP
Which agents are okay?
Which aren't?
* ALL gases, nitrous, prop, high dose BZD (↑ late & ↓ amp)
* Ketamine & etomidate increase amplitude
* little effect from opioids, low dose BZD
* no effect from NMB
98
Ketamine
* NMDA antagonist (non competitive) blocks glutamate
* Stimulates SNS
* inhibits NE reuptake
* Analgesia via opioid receptors
99
Ketamine
dosing
* 0.5-2 mg/kg IV
* 4-5 mg/kg IM
* “Bad” epidural/spinal: 10-20 mg
100
Ketamine
Contraindications
* severely ill or shock → catecholamine depletion → profound CV depression
* increase ICP
* R heart dysfunction
101
Ketamine for spines and brains
good for spines, bad for brains
102
Ketamine and seizure activity
Does NOT lower seizure threshold & has anticonvulsant activity
103
Etomidate is a .... derivative
Carboxylated imidazole
## Footnote
GABAa agonist
104
Etomidate
pain on injection
ethylene glycol
105
Etomidate
Neuro effects
* myoclonus
* decreases CMRO2, CBF & ICP
* Direct vasoconstrictor (decreases CBF before suppressing metabolism)
* good for ECT
106
Etomidate's
adrenocortical suppression
inhibits 11β-hydroxylase
❌ cholesterol → cortisol
107
Can etomidate be used for ECT?
Yes
* EEG: initially increases α amplitude → progressive decreased activity
* lengthens seizures
108
T/F:
Etomidate should not be given to pts with seizure disorders.
True
109
Morphine
&
Fentanyl
receptor activity
Morphine: Mu-1, mu-2, K
Fentanyl: Mu-1, mu-2, K
110
Fentanyl strength vs morphine
100x stronger than morphine
111
Morphine and Fentanyl share these effects...
* decr CO2 sensitivity
* euphoria
* sphincter of Oddi spasm
* resp depression
* sedation
* constipation, N/V
* miosis
* bradyHR
112
this opioid has more occurrence of itching bc....
morphine
histamine release
113
lipophilicity of moprhine vs fentanyl
morphine: low lipophilicity (slow to cross BBB)
fentanyl: high lipophilicity (high Vd)
114
morphine & fentanyl dosing
morphine: 0.1 mg/kg
fentanyl: 0.5 -1 mcg/kg
- Maintenance: 25 – 50 mcg
- Post-op: 50 – 100 mcg
- Infusion: 0.01 – 0.05 mcg/kg/min
115
morphine
vs
fentanyl
doA
morphine 2-7 H
fentanyl 10-20 min
116
T/F:
Morphine and fentanyl will markedly decrease CBF and CMRO2.
False
minor reduction if any effect
117
MAO’s
A primary class of antidepressants
118
Monoamine oxidase inhibitors (MAO-I's)
inhibiting MAO = ↑ norepi **released** from terminal
## Footnote
no longer common bc SEs
119
The MAOIs
* methylene blue
* phenelzine (Nardil)
* tranylcypromine (Parnate)
* isocarboxazid (Marplan)
* clorgyline
120
MAOIs should not be combined with
which agents & why
* tyramine (HTN crisis)
* SNS mimetics (HTN crisis)
* TCAs (HTN crisis, tachy♡, seizures)
* SSRI (Serotonin synd)
* meperidine (HTN crisis, CV collapse)
121
Serotonin syndrome
S/S
Fever, agitation, NM irritability, hypotension, coma, death
122
Dont combine MAOIs with sympathomimetics such as...
* Reserpine
* Ephedra (Ma-huang)
* Amphetamines
* Phenylephrine
123
Flumazenil
moA
Competitively inhibits benzo binding to GABA
(benzo overdose)
124
Flumazenil
-dose
-overdose
* 0.2 mg
* Repeat in 45 sec then every min **UP TO 1mg**
* Risk for **seizures** with large doses
125
Neostigmine
moA
* AChE inhibitor (anticholinesterase)
* Prevents the breakdown of Ach by acetylcholinesterase
126
Neostigmine is a _____ ammonium
QUAT
does not cross BBB
127
Neostigmine Dosing
* 0.04-0.08 mg/kg
* Max dose: 5 mg or 70 mcg/kg, whichever comes first
* 0.2 mg glyco per 1 mg of neostigmine
128
Neostigmine
considerations
* can cause vagal response
* must have twitches before giving or can prolong block
* NV, prolonged QT
## Footnote
muscarinic stimulation → bradyHR, bronchoconstriction, secretions, incr bowel motility
129
Neostigmine
-onset
-doA
Onset: 15 min
Duration: 1-2 hr
130
APFEL
PONV
## Footnote
not to be confused with PDNV
131
PDNV
