Misunderstood/Diff Topic Flashcards
True/False
Neuronal pathway for reflex withdrawal of a limb in response to a painful stimulus is mediated by the cerebral cortex.
False
_____ toxicity can develop in patients with renal failure who receive nitroprusside infusion.
Thiocyanate
Risk factors for development of persistent postoperative pain include
_______
psychosocial issues,
preoperative pain severity and postoperative pain severity.
During non-depolarizing neuromuscular blockade, fade with train-of-four stimulation is the result of ______
ion channel blockade at the neuromuscular junction.
Hepatopulmonary syndrome triad
- Liver dysfunction
- Hypoxia
- Intrapulmonary vascular dilation
*Unique positional change: worsening hypoxemia when standing, improved when supine
Portopulmonary HTN
Pulmonary HTN that exists in pt that has Portal HTN
- mean PAOP >25 mmHg at rest
How does magnesium prolong NMB?
Prejunction effects
- Inhibits Calcium channels at presynaptic junction -> prevent release of ACh
Post junctional effects
- decreases muscle fiber membrane excitability
Insulin exerts an (anabolic/catabolic) effect on the body
anabolic
- Increases glucose uptake
- Increases aa uptake
- Increases fatty acid storage/synthesis
*insulin inibits catabolic processes (glycogenolysis, lypolysis, proteolysis), opposes glucagon and cortisol
Ideal time period to quit smoking is ___ weeks. Why?
4-8 weeks
- decrease airway reactivity
- increase bronchial ciliary motility -> enhance mucous clearance
- decrease carbon monoxide lvls -> increase oxygen carrying capacity of hgb
Broken down Henderson-hasselbalach equation
pH = HCO3-/PaCO2 (kidneys/lungs)
*describes interrelated PaCO2, pH, and HCO3-
When does “anion gap” occur?
What is normal?
When metabolic acidosis occurs and the body has an excess of anions.
- The acid dissociates into H+ and an unmeasured anion. H+ is buffered by bicarb, and the unmeasured anion accumulates in the serum
Normal is 10 +/- 2
What is PaO2?
measurement of the oxygen tension in plasma
aka
Dissolved oxygen in plasma
Which analyzer is affected by water vapor, paramagnetic or galvanic?
Paramagnetic analyzers (ie: desflurane)
- bc water vaper is diamagnetic, and will oppose the paramagnetic effect of O2
- Paramagnetic devices are incorporated with a water trap from the sampled gas
Response to succinylcholine
- GBS
- MS
Upregulation of extrajunctional ACh receptors
and
increased hyperkalemic response to succs
*do not give
Response to succinylcholine
- Myasthenia gravis
Increased resistance to succinylcholine
*can be given
Response to succinylcholine
- Lambert-Eaton Myasthenic syndrome
Extremely sensitive to succs
*can be given
Guillan barre syndrome
- Autonomic dysfunction seen
- Labile BP
- Orthostatic Hypotension
- Arrhythmias
- Circulatory collapse
Every pt that receives anesthesia must have (4)
- Pre anesthesia eval
- w/in 48 hr to procedure, some elements no more than 30 d prior
- Review medical/surgical hx, meds, allergies, devel plan
- Post anesthesia eval w/in 48 h post surg
The _____ is the only organ that receives a dual blood supply. What happens if there is a reduction in blood flow?
liver
- hepatic a (25%) and portal v (75%)
Increase in adenosine in liver -> local arteriole dilation and increase in blood flow from hepatic a.
Desflurane has an extremely (High/Low) vapor pressure and is significantly vaporized at RT. How is this adjusted for?
High - 669 mmHg
Desflurane requires a heated vaporizer to maintain constant vaporizer output [ ], to account for evaporative cooling of des
3 major mechanisms for nitroprusside toxicity
- Cyanide ions bind to cytochrome C oxidase and inhibit cellular aerobic respiration
- Formation of cyanmethemoglobin (unable to carry O2)
- Thiocynate production (CNS related fx)
Local anesthetic systemic toxicity (LAST) usually occurs __ hours after the procedure
10-16h when plasma [ ] of local anes typically peaks
Prior to an awake intubation, percutaneous nerve blocks can be used to anesthetize the airway
- Transtracheal injection of local anesthetic will block ________, which provides _________
Recurrent laryngeal n., branch of vagus n.
- Sensory innervation to vocal folds and trachea
Most common risk of NSAID use in elderly
dyspepsia (20%)
*more than renal toxicity
Dexmedetomidine (alpha 2 agonist) is metabolized ________.
in the liver, Cyt P450
- minimal changes noted with renal disease
______ is the main mechanism for pt heat loss in the OR following initial redistribution of heat to the periphery
Radiation - 67%
Bronchopulmonary dysplasia in preterm infants
- What is it
- Characterized by (4)
chronic disease of lung parenchyma, a sequelae of respiratory distress syndrome
Characterized by:
- peribronchiolar fibrosis
- disorganized pulmonary vasculature
- airway smooth muscle hyperplasia
- enlarged alveoli
During electroconvulsive therapy, there is a brief initial ______ surge followed by a ______ response. How is this manifested in their monitor?
Parasympathetic
followed by sympathetic
Brief bradycardia
followed by significant tachycardia and HTN
- manage w/ esmolol, labetalol, nicardipine, clevidipine, nitroprusside
With the hepatic arterial buffer response, hepatic arterial tone is modulated by ________ via _____ in order to maintain hepatic perfusion
portal venous flow via adenosine
Effects on Hepatic arterial flow
- Glucagon
- Angiotensin II
- Vasopressin
- Glucagon: vasodilation
- Angiotensin II: vasoconstriction
Treatment of tracheoesophageal fistula (can’t pass OG tube, excessive oral secretions) is ________
Kasai procesure - jejunal roux-en-y plus portoenterostomy
VACTERL
Vertebral abnl imperforate Anus Congenital heart disease TracheoEsophageal fistula Renal abnl Limb abl
How to prevent ECG burns in the MRI scanner
- Which law does this follow?
prevent any coiling or loops
- Faraday’s law: current in wire is directly proportional to the number of turns (coils) present
Autonomic dysreflexia
- Signs under GA
- Signs awake/light anesthesia
- Signs under GA: HTN, bradycardia
- Signs awake/light anesthesia: profuse sweating, facial erythema, piloerection, feeling of doom
GCS mneumonic
Eyes (4)
Vocal (5)
Motors (6)
*# of letters in each category
Partial compression of the aorta/IVC will cause _____ BP in the upper extremities and _____ in the lower extremities
increased
decreased
*ie: aortocaval compression > 20 weeks pregnancy
____________ should be first line tx of bronchospasm during ETGA
increasing O2 [ ] to 100% (FIO2)
What is unique in transplanted lungs?
Denervated and cough reflex and mucociliary function impaired
Lymphatic drainage absent
Scopolamine, antimuscarinic can cause paradoxical ______ when given in low doses (0.1 mg)
paradoxical bradycardia
PT/INR is typically increased in cirrhosis d/t ______
decreased production of coagulation factors in the liver
Crawford classification of aortic aneurysms
- I
- II
- III
- IV
- I: descending thoracic and upper abdominal
- II: all or most of the descending thoracic and abd
- III: inferior portion of the descending thoracic and most of the abd
- IV: all or most of the abdominal aorta
Crawford type __ aortic aneurysm has the greatest risk of spinal and renal ischemia
Type II
- mortality of 20%
Spinal cord perfusion pressure =
MAP - CSFP
*cerebral spinal fluid pressure
Spinal cord and kidneys are at risk for ischemic injury during open thoracoabdominal aneurysm repair. Protective techniques for spinal cord include __ (4)
- Shunts
- Bypass
- Hypothermia
- Spinal drain placement
Why do obese pts rapidly desaturate with periods of apnea?
They have markedly reduced FRC, which narrows the gap btwn closing capacity and TV
*closing capacity: volume at which the respiratory bronchioles begin to collapse. residual volume + closing volume
Treatment for postherpetic neuralgia
- TCA
- Opioids (tramadol - opioid + SNRI)
- Gabapentin/pregab
*NSAIDS are useless
Glucagon (raises/lowers) blood glucose levels. How?
Glucagon (stimulates/impairs) lypolysis and (stimulates/impairs) glycolysis
raises by stimulating glycogenolysis and gluconeogenesis
Stimulates lipolysis
Impairs glycolysis
__________ blocks provide fast, reliable, surgical anesthesia of the upper extremity, and are ideal for surgical procedures performed at or below the elbow
Supraclavicular block
_______ blocks are best for shoulder and upper arm surgeries
Interscalene block
- proximal portion of the brachial plexus
______ is a second messenger that causes smooth muscle relaxation, bronchodilation, vasodilation, and tocolytic effects.
cAMP
*also increases cardiac contractility
Malignant hyperthermia is inherited in which fashion?
Autosomal dominant with incomplete penetrance
What should you avoid in pts with sickle cell in the OR?
Prolonged tourniquet time Hypoxia Dehydration Cold Acidosis
Vasopressin’s structure is similar to _____ oxytocin. Differ by 2 amino acids
oxytocin
Exhibit cross reactivity at high plasma [ ].
Is: vaso can cause uterine contractions
Oxytocin can inhibit diuresis
___ stimulates vasopressin secretion, while ___ inhibits secretion
AT2 (angiotensin II from RAAS)
ANP
What type of info is seen on the National Practitioner Data Bank (NPDB)
- Medical malpractice payments
- Certain adverse licensure actions by state boards
- Certain adverse clinical privileges actions
- Certain adverse professional society membership actions
- DEA controlled-substance registration actions
- Exclusions from medicare, medicaid, and other federal healthcare programs
On pressure support, a breath is triggered when a pt produces a _____ above a preset _____
flow rate
flow trigger
What is the Time Constant?
The volume or capacity of the circuit (Vc) divided by the fresh gas flow (FGF)
Vc / FGF
What accounts for the the most heat loss during GA?
Radiation - heat loss from infrared heat
Dyspnea shortly after tumescent liposuction is most commonly caused by _______
Fluid overload and pulmonary edema
- injection of very large volumes of saline
