Board Review Flashcards
Pass Boards
Phospholamban
- Inhibits the affinity of SR Ca ATPase for Ca
- phosphorylation relieves inhibition
SERCA
sacroplasmic reticulum Ca ATPas
Gs
- GDP –> GTP
- adenylate cyclase converts ATP –> cAMP
- PKA –> Ca release
- receptors: beta 1, 2, D1, V2
Gi
- reduce cAMP formation
- receptors = alpha 2
Flow =
change in pressure / resistance
Pm =
mean circulatory pressure (flow = 0)
Cerebral vasodilators
- CO2
- NO
- prostacyclin
- ET-1
- increased metabolism
CVP waveform - a wave
atrial contraction, = RVEDP
CVP waveform - c wave
early systole - TV elevates into the RA
CVP waveform - x descent
atrial relaxation
CVP waveform - v wave
filling of RA in late systole
CVP waveform - y descent
TV opens and RV passively fills
CVP waveform - cannon a-waves
AV discordance
CVP waveform - fused C-V waves
TR
Normal CI
3.3-6 L/min/m2
Fick Equation
CO = VO2/(CaO2 - CvO2)
Thermodilution - AUC
inversely proportional to CO
Shunt fraction
Qs/Qt = (CpvO2 - CaO2)/(CpvO2 - CvO2)
Normal shunt fraction
3-7%
O2 extraction ratio (ERO2)
avDO2/CaO2 (normal = 25%)
SVR =
(MAP - CVP)/CO
PVR =
(MPAP - PCWP)/CO
Qp/Qs =
(SaO2 - SvO2) / (PpvO2 - SpaO2)
alpha-1 receptor
Gq –> increased IP3, 1,2-DG and Ca
alpha-2 receptor
Gi –> decrease cAMP
beta-1 receptor
Gs –> increase cAMP
beta-2 receptor
Gs –> increased cAMP
D1 receptor
Gs –> increased cAMP
Gq
- phospholipase C (PLC) –> IP3 and DAG
- PKA –> increase Ca
- receptors: alpha 1, V1
V1 receptor
Gq; vascular bed and CNS
V2 receptor
Gs; renal collecting ducts
Vasopressin stimulation
- osmolality changes
- change in BP of blood volume
Milrinone MOA
PDE3 inhibitor (prevents hydrolysis of cAMP)
Nesiritide
recombinant BNP –> direct vasodilation
Digoxin MOA
Inhibits Na/K ATPase –> increased intracellular Ca
Digoxin toxicity potentiated by
- hypoK
- alkalosis
- hypoxemia
- catecholamines
Mobitz type 1
progressively prolonged conduction; AV node
Mobitz type 2
abrupt failure to conduct; His conduction system
Pacing Terminology
Paced; Sensed; Response
Adenosine side effects
sinus arrest, bronchospasm, vasodilation
Action Potential - Phase 0 drugs
Quinidine, Procainamide, Lidocaine, Phenytoin, Flecainide
Action Potential - Phase 2 drugs
Verapamil, Diltiazem
Action Potenial - Phase 3 drugs
Amiodarone
CaO2 =
(1.34 x Hgb x SaO2) + (0.003 x PaO2)
CaO2 units
mL O2/dL
Hemoglobin Saturation Curve - Left Shift
- increased affinity for O2
- decrease in CO2, temp, DPG
Hemoglobin Saturation Curve - Right Shift
- decreased affinity for O2
- increase in CO2, temp or DPG
Cardiac Transplant - Hyperacute Rejection
HLA comparability; Tx = PLEX
Basiliximab
IL_2 receptor Ab
ATG MOA
T cell lysis
Calcinuerin inhibitors
T cell inhibition; ex = cyclosporine, tacrolimus
LaPlace’s Law
P = 2T/r
Time constant =
R x C; time it takes for volume of respiratory system to decrease by 63%; normal 0.3 sec (children)
Dead Space Fraction =
PaCO2 - PetCO2 / PaCO2
Hypoxic Regulation of Breathing
Ventilation increases steeply if PaO2 < 50 (not O2 content)
Hypercarbic Regulation of Breathing
- H+ - carotid body
- PaCO2 - brainstem/medulla
- hypoxia –> augmented reponse
PAO2 =
- FiO2 x (Patm - PH2O) - PaCO2/R
- Patm = 760
- PH20 = 47
- R = 0.8
Normal A-a gradient
5-10 (increases with age)
Diaphragm Muscle Fiber
- type I = fast twitch
- type II A = good endurance
- type II B = more susceptible to fatigue
Intercostal Muscles
- external –> inspiration
- internal –> expiration
Treatment of Invasive Aspergillosis
Voriconazole
Tidal Volume - Normal
7 mL/kg
Vital Capacity - Norma
65 mL/kg
Residual Volume - Normal
15 mL/kg
FRC - Normal
30 mL/kg
FRC =
Expiratory Reserve Volume + Residual Volume
Myclonic spasm
Spinal cord mediated
DKA - risk factors for cerebral edema
- Demographic: new onset, male, < 5 yo
- Labs: hypocarbia, increased BUN
- Treatment: bicarbonate
Osmolality =
2 x NA + glucose/18 + BUN/2.8
Toxic metabolite of APAP metabolism
- NAPQI
- combines with glutathione –> non-toxic conjugates
Octreotide
synthetic long-acting form of somatostatin
Liver failure - cerebral edema
NH3 –> astrocyte –> glutamine
Methemoglobinemia
- heme in ferric state unable to bind O2
- Dx = co-oximetry (> 30% –> symptoms)
- Tx = methylene blue
Organophosphate symptoms
SLUDGE or DUMBELS
Organophosphate mechanism
Binds acetylcholinesterase (AchE) –> increase Ach
Organophosphate treatment
- Pralidoxime = reactivates AchE
- Atropine = muscarinic receptor antagonist
RMSF rash
- wrists/ankles –> trunk
- erythematous/macular –> petechial
RMSF lab findings
thrombocytopenia, anemia, hypoNa
Neurologic complications of hypernatremia
- SDH - tearing of bridging veins
- CVST - hyperosmolality
Arterial line - dampening
- decreased SBP
- increased DBP
- capacitance increased by air bubbles, compliant tubing
Arterial line - ring
- increased SBP
- decreased DBP
- high spike
- resonance in system
GABA
- main inhibitory NT in CNS
- Cl channel complex = binding site for BZD and barbituates
Metolazone
- thiazide like diuretic
- inhibits Na reabsorption in the proximal convoluted tubule
- produces diuresis even in GFR is low
Myasthenia gravis pathophysiology
- autoimmune reduction in number of Ach receptors on skeletal muscle
- symptoms appear when < 30%
Long QT syndrome
- associated with congenital deafness
- avoid volatile anesthetics, ketamine, succinylcholine
Most common FA oxidation defect
MCAD
EKG findings in hyperkalemia
narrow peaked T-waves –> prolonged PR and widened QRS –> sine wave
Timing of DAH after BMT
Peri-engraftment period
Pneumococci gram stain
lancet shaped gram postive diplococci
VOD risk factors
- female
- abdominal radiation
- elevated AST
- HLA disparity
Pharmacokinetics in infants
- elevated gastric pH
- slower gastric emptying and intestinal motility
- increased % body water
- lower capacity for protein binding
Renal failure in rhabdomyolysis
- rerrihemate
- tubular obstruction by myoglobin casts
- alteration in GFR
Uncal herniation
- lateral mass lesion
- temporal lobe herniates medially into tectorial notch
- stretching of 3rd CN
Transtentorial
downward displacement of thalamus and hypothalamus
Myocyte resting state
actin inhibited from binding to myosin by troponin-tropomyosin complex
CSF passageways
- foramen of Monro = lateral ventricle to 3rd ventricle
- aqueduct of Sylvius = 3rd to 4th
- foramen of Magendie and Luschka = outlets of 4th ventricle