APEX Flashcards
What lung volume increases with aging?
Residual Volume
What are usually the first signs of PE?
A precipitous fall in EtCO2 and tachycardia
also hypotension, bronchospasm
What are the treatment options for PE?
- Immediate treatment is 100% FiO2 and hemodynamic support with IV fluids and inotropes
- The pulmonary embolectomy or thrombolysis if needed
What is an indication for retrograde Intubation?
Cervical Spine Injury
What is the most reliable method to reduce postoperative pulmonary complications?
Smoking Cessation
Anesthetic management of patient undergoing surgery for Bullae removal?
- Spont. Ventilation till the chest is open
- Small TV with high RR
- Avoid N2O
- DLT preferred
What are the 4 nerves involved in the airway?
Glossopharyngeal
RLN
Internal SLN
External SLN
What happens to the airway if the vagus nerve is damaged?
Unilateral: hoarseness
B/L: Aphonia
What happens to the airway if the external branch of the SLN is damaged?
Unilateral: Minimal effects
B/L: Hoarsness/easily fatigued voice
What happens to the airway if the Internal branch of the SLN is damaged?
Sensory only NO effect on vocal cords
What happens to the airway if the RLN is damaged?
Unilateral: Hoarsness
B/L: Stridor, Dyspnea (acute injury), aphonia (Chronic injury)
What are the sizes of LMA based on weight?
LMA 1 = <5kg LMA 1.5 = 5-10 kg LMA 2.0 = 10-20 kg LMA 2.5 = 20-30 kg LMA 3.0 = 30-50 kg LMA 4.0 = 50-70 kg LMA 5.0 = 70-100 kg
What are the respiratory changes that occur with inadequate pain management?
- Decreased VC, TV, TLC, & FRC
- Decreased ability to clear secretions
Where is the inspiratory pacemaker?
The DRG
What is primarily responsible for causing active exhalation?
The VRG
What area triggers inhalation?
The Apneustic center (stimulations the DRC)
What area triggers the end of inhalation?
The pneumotaxic center
Inhibits the DRC
What is the AFFERENT limb of the oculocardiac reflex?
Long and short ciliary nerves > ciliary ganglion > ophthalmic division of the trigeminal nerve > Gasserian ganglion
What is the initial dose for cardio version of A-Fib?
50-100 Joules
How long to delay elective surgery for drug eluting stent?
6 Months
bare metal stent minimum 30 days
Formula for MAP?
1/3 SBP + 2/3 DBP
What drugs do not affect SSEP’s?
Ketamine, precedex, etomidate, opioids, and droperidol
VAA most affected by right to left shunt?
Desflurane (low solubility 0.42)
What are the components of LA?
- Aromatic ring: confers lipid solubility
- Intermediate chain: determines metabolism and allergic potential
- Tertiary amine: confers water solubility
What effect does Mu receptor activation have on the nerves in the dorsal horn?
- Inhibits adenylyl Cyclase > Dec cAMP
- Presynaptic nerve: Decreased CA conductance > decreases neurotransmitter release
- Postsynaptic Nerve: Increase K-conductance hyper polarizes the cell
List the events that correlate with 50, 60, 70, and 80% blockade
- 80%: TV > 5mL/kg
- 70%: TOF 4/4
- 60%: Double burst w/o fade
- 50%: Bite tongue blade for > 5 seconds
Only narcotic that is known to prolong QT interval?
Methadone (Can cause torsades)
How to calculate width of BP cuff?
40% of the circumference
What happened if the BP cuff is too small? too big?
- Too small: false high
- Too big: false low
What does Near Infrared Spectroscopy (NIRS) measure?
Near Infrared Spectroscopy (NIRS) measure cerebral venous oxygen saturation
- limitations: only measures regional saturation (prefrontal cortex) and is not useful for global ischemia
Airway complication seen with adenosine?
Bronchospasm (especially in asthmatics)
Draw the SODA LIME reaction
1) CO2 + H2O H2CO3
2) H2CO3 + NaOH –> Na2CO3 + H2O + heat
3) Na2CO3 + Ca(OH)2 CaCO3 + NaOH
The only CCB that has been proven to reduce the risk of morbidity and mortality from cerebral vasospasm?
Nimodipine
How do changes in PaCO2 affect cerebral blood flow?
For every 1 mmHg change in PaCO2 from 40 mmHg, CBF changes in the same direction by 1-2 mL/100g/min
What factors increases the risk of ischemic optic neuropathy in patients undergoing spinal surgery?
- Low ratio of colloid to crystalloid resuscitation
- Greater estimated blood loss
- Use of a Wilson frame
- Male sex
- Obesity
- Long duration of anesthesia
What is the timeframe for decompression of spinal hematoma?
Within 8 hours
What are the signs of spinal hematoma?
Bowel or Bladder dysfunction
Lower extremity weakness
Lower Ext. sensory deficit
Back Pain
List the brachial plexus cords and the nerves they give rise to
1) Medial cord -> ulnar nerve
2) Medial + Lateral -> median nerve
3) Posteror cord -> Radial Nerve
Needles with highest risk of PDPH
Quincke and Pitkin
Analgesia from lipophilic opioids
most likely through systemic actions (aka fentanyl and sufentanil)
Sensation to the webbed space between the thumb and index finger is through what nerve?
Radial nerve
Formula to determine amount of BiCarb to administer to arrive and desired HCO3 level
(Change in HCO3 x kg x 0.3)/2
What are some common causes in intraoperative hypocalcemia?
Hyperventilation
Administration of pRBC
Rapid correction of hyponatremia may result in
Central Pontine Myelinolysis
- Demyelination of neurons
- Spastic quadrioaresis (demyelination fo motor neurons), psudobulbar pasly, mental dysfunction, and death
What are the S/S of hypercalcemia?
HTN
Hypotonia
SHORT QT interval
Polyuria
Dehydration
Cognitive dysfunction
What are indicators of liver synthetic functions?
PT
INR
Albumin
What are indicators of hepatocellular injury?
AST
ALT
GST
What are indicators of cholelithiasis?
Y-Glutamyl Transpeptidase (GGTP)
Alkaline phosphatase
What is the dose for mannitol?
0.25-1 g/kg
How does a carcinoid crisis present?
Flushing, diarrhea, HTN or Hypotension, ABD Pain, Tachycardia
What drugs can precipitate a carcinoid crisis?
Succ, Atracurium, Thiopental, Epinephrine, NE, or Iosproterenol
Medications that are useful in the management of carcinoid tumors?
Ondansetron and Ocreotide
Why do we decrease the dose of etomidate in the elderly?
Decreased Vd and clearance
What is the onset time for postoperative delirium?
1-5 days post op
Anterior wall defect that is commonly associated with other defects
Oomphalocele
Gastroschisis is most common in
Prematurity
Areas assessed during aldrete scoring
Activity Neurologic Status O2 Saturation Respiration Circulation
A non-painful stimulus that evokes a painful response
Allodynia
An exaggerated pain response
Hyperalgesia
Pain localized to a dermatome (peripheral nerve)
Neuralgia
An abnormal painful sensation
Dysesthia
What is the formula for BMI
kg/m2
Antitumor antibiotics
Bleomycin and Doxorubicin
What are the nerve roots of the celiac plexus?
T5-T12
Side effects from celiac plexus block?
Hypotension (Most common)
Diarrhea
Bowel, Kidney, Puncture
Retroperitoneal hemorrhage
Most common cause of intraoperative allergic reaction?
Muscle relaxant
latex second most common
A circumstance that won’t benefit from supplemental oxygen
Pulmonary edema (right to left shunt
List the 5 causes of arterial hypoxemia
1) Low FiO2- high Altitude
2) Hypoventilation- Opioid overdose
3) Diffusion impairment - Pulmonary fibrosis
4) V/Q Mismatch- COPD
5) Shunt- Pulmonary Edema
Examples of acute intrinsic restrictive disease
Pulmonary edema
Aspiration Pneumonia
ARDS
Examples of Chronic intrinsic restrictive disease
Idiopathic Pulmonary Fibrosis Radiation Injury Cytotoxic Drug Oxygen toxicity sarcoidosis autoimmune disease
When is it recommended to redose a citrated antacid
1 hour after 1st dose
What is the formula for PAO2? PaO2
- )PAO2 = FiO2 x (Pb x 47 mmHg) - (PaCO2/0.8)
2. ) PaO2 = PAO2 - A-a Gradient
What axis must be aligned for intubation
Oral
Pharyngeal
Laryngeal
DLT insertion depth
29 cm in males
27 males in females
MOA of A2 agonist
GPCR (Gi) inhibit adenylate cyclase and therefore cAMP
When do we see pulses biserfiens
Aortic regurgitation
Pulsus alternans is seen with
Systolic left ventricular failure
pulses parvus is seen with
aortic stenosis
What INCREASES after infrarenal cross clamp placement?
Preload,
Mixed venous O2 saturation
How to identify the VAA based on the organic molecule structure?
Sevo: 7 fluoride
Des: 6 fluoride
Iso: 5 fluoride
Halothane 3 fluoride, 1 Cl, 1 Br
Clearance is inversely proportional to
- Half-Life
- Concentration in the central compartment
Drugs to avoid in patients with porphyria
All barbs and etomidate
Consideration for patients with Acute Intermittent porphyria
Liberal hydration
Glucose supplementation
Prevention of hypothermia
CV changes of N2O
(it affects the SNS)
Increased SVR, BP and HR
N2O inhibits what pathway
Methionone synthase: B-12 metabolism and DNA synthesis
What enzyme is inhibited by etomidate?
11-beta- hydroxylase (inhibits stereos synthesis)
What drug is the most potent amnestic?
Lorazepam
Order the opioids based on context sensitive half lives
Fentanyl (Longest) > Alfentanil > Sufentanil > remifentanil (Shortest)
What muscle is monitored when evaluating twitches from the ulnar nerve?
Adductor Pollicis
Components of EMLA cream
2.5% prilocaine and 2.5% lidocaine
Time for onset with EMLA
60 minutes
Rank the speed of LA absorption after injection based on speed
Interplerual > Intercostal > Caudal > Brachial plexus
List the hydrophilic opioids
Morphine, meperidine, hydrocodone
List the Lipophilic opioids
fentanyl, sufentanil
Describe mass spectrometry
bombards the gas sample with electrons
Describe Raman Scatter Spectrometry
uses a high powered argon laser to produce photons; scattered photons are then measures
Describe the use of piezoelectric crystals
detects individual gases by their interaction with a lipid bilayer crystal
How to calculate TV for a machine that couple FGF
1) convert FGF to mL/min
2) FGF x fraction spent in inspiration [using I:E; I/(I+E)]
3) divide anger by RR
4) add value to set TV
Best ECG lead for rhythm abnormalities
Lead II
Where is CSF reabsorbed
in the arachnoid villi of the saggital sinus
CSF production rate in the choroid plexus
30 mL/hr
Classic presentation of autonomic hyperreflexia
HTN and Bradycardia
- Vasoconstriction below lvl of injury
- Vasodilation above lvl of injury
- LV failure may lead to Pulmonary edema
- Cerebral HTN may lead to seizures
Diseases that increase the risk of MH
Central core Disease
Minicore disease
King Denborough Syndrome
Sensory innervation of the median nerve is to what part of the hand?
1) Palm of hand
2) Ventral region of the thumb
3) Distal index, middle, and medial half of the ring finer
Triggers for a sickle crisis
Pain
hypothermia
acidosis
dehydration
What is non gap acidosis
Due to loss of HCO3 (or increased Cl)
- Examples diarrhea, renal tubular acidosis, excessive sodium chloride administration
The triad for metabolic syndrome
HTN, Obesity, DM
What are the hormones released from the POSTERIOR pituitary gland?
ADH and oxytocin
What are the hormones released from the ANTERIOR pituitary gland?
FLAT PiG
- Follicle stimulating hormone (FSH)
- Leuteinizing Hormone (LH)
- Adrenocorticotropic hormone (ACTH)
- Thyroid Stim. Hormone (TSH)
- Prolactin
- Growth Hormone (GH)
Hypoadrenalism is also known as?
Addisons disease
What are the anesthetic considerations for patients with hypothyroidism?
- Airway compromise (ex. goiter)
- Hypothermia
- Hypotension
- Aspiration (D/t gastric emptying)
- Faster VAA induction
- NO effect on MAC
What is the function of gastrin?
stimulates pepsinogen secretion
What is the function of secretin?
Stimulates bile flow
What is the function of Motilin?
Stimulates upper GI motility