Basic 3 Flashcards
Alcoholic derangements
hypokalemia, hypomagnesemia, hyponatremia, hyperuricemia, metabolic acidosis, and respiratory alkalosis
Sevo mask induction
- avoids salivation
- benzos improve technique
- opioids worsen technique
- spontaneous ventilation is preserved
- stage II is usually not seen
Diagnosis of OSA
requires a sleep study Snoring Tired during the day Observed apneas Pressure (high blood pressure) BMI > 35 Age >50 Neck size >40cm Gender (male)
Non compensating pneumatic bellow:
A noncompensating pneumatic bellows ventilator system does not take into account the added volume from FGF during inspiration when delivering a set tidal volume.
Angle of error with US doppler
20%
anything higher will have statistically different results
Anesthesia drug abuser facts
40% relapse
only 34% successfully reenter anesthesia
2nd messenger for insulin and glucagon
cAMP
Elevated CPK in heavy patient
most likely due to immobilization
Decreases osmolality if given several litters
LR
Plasma osmolality (Posm)
Plasma osmolality (Posm) = 2 x [Na] + [glucose]/18 + blood urea nitrogen/2.8
Middle cardiac vein runs with what?
PDA
Great cardiac vein runs with what?
LAD
anterior cardiac vein runs with what?
right coronary artery
Blood reactions
Acute hemolytic : ABO incompatability
febrile : cytokine and antibodies to leukocyte antigens
graft v host: donor lymphocytes reacting against recipient
delayed hemolytic: donor RBC antigens
metformin
- biguinide
- primary action is decreasing hepatic gluconeogenesis and increasing insulin sensitivity
- take morning of surgery unless kidney issues
Prolonged in kidney injury
- neostigmine is 50% renally secreted
- Vec is 25%
- Roc is 10%
TBI guidlines
- maintain CPP 50-70 mmHg
- hyperventilate to PaCo2 25 mmHg
- treat ICP > 20 mmHg
1 ml of liquid volatile gas
- 200 ml of vapor
Liquid volatile anesthetic (mL/hr) ≈ 3 * FGF (L/min) * % anesthetic vapor
Compliance equation of respiratory systerm
1/CRS = 1/CL + 1/CCW
Where C is compliance, RS is respiratory system, L is lungs, and CW is chest wall
Highest MAC requirement
Endotrachial intubation ( cords are very stimulated)
Hypokalemia
<3.5
- increases resting membranes and increases both the duration of the refractory period and duration of the action potential
- ST depressions
- T wave depressions
- U waves
- QT prolongation
Hyperkalemia
> 5.5
- Resting potential is less electronegative; initially depolarizes but repetition causes inactivation of fast Na channels leading to impaired cardiac conduction and contractility
- peaked t waves
- PR and QRS lengthening
- QRS can develop into sinusoidal wave
- stabilize the heart with calcium
- treat with insulin (with glucose), albuterol and sodium bicarb
Hypocalcemia
< 8.5
- impairs cardiac conduction and contractility
- hypotension, Trousseau, Chvostek, seizures
- prolongation of QT with increased ST segment and normal T wave
Hypercalcemia
> 10.5
- shortening of QT interval, abrupt upslope of T wave
- IV saline to dilute, calcitonin and bisphosphonates
Hypomagnesemia
<1.5
- associated with higher carotid intima medial thickness and risk factor fir coronary disease.
- long QT and arrythmias
- neuromuscular excitability, seizures, AMS
Hypermagnesemia
- 4-6; neuromuscular effects, HA, lethargy, decreased DTR
- > 6: hypotension and bradycardia; progresses to heart block and cardiac arrest
- prolongation of the PR interval,
- increased duration of the QRS complex
- increase QT interval
Hepatic Blood Flow
Hepatic Artery: 25% blood flow with 75% O2
Portal vein: 75% and 25 O2 (rich in nutrients absorbed through the gastrointestinal track)
- flow is controlled by arterioles in the preportal splanchinic organs and by the resistance within the liver
- surgical stimulation , when combined with the effects of anesthetics can decrease total hepatic blood flow by 30-40%
Nephron
- Proximal tubule: reabsorption of Na by active transport.; H2O and Cl usually follow passively
- Loop of Henle: some Na is reabsorbed
- Distal tubule: impermeable to H2O and Na. Ca reabsorption (PTH)
Renal blood flow
-Calculated with PAH
RBF = RPF/(1-Hct)
RPF = ([PAH urine}/[PAH plasma]) X urine flow
GFR
= [( urine creatinine X (urinary flow rate)]/plasma creatinine
Nalbuphine
mu opioid receptor antagonist and a kappa receptor agonist. It is classified as a mixed opioid agonist-antagonist.
-exhibits a plateau effect for respiratory depression
propofol extravasation
- not likely to cause local tissue injury
pretreatment of NDMB prior to RSI
- does not blunt the rise in intraocular pressure (IOP) seen with succinylcholine administration
- can prevents fasciulations, increased gastric pressure, ICP
Effect of supine position on FRC and CC
decreased FRC
- no change in CC
insulin-independent glucose transport
Hepatocytes, most immune cells, erythrocytes, and brain neurons
2- chloroprocaine onset time
6-12 minutes
St. Johns wart
- induces CYP450
- can alter drug responses with anti-rejection medications, warfarin, and intraoperative anesthetics
TRALI
1) Acute lung injury (ALI)
- Acute onset
- Hypoxemia (PaO2:FiO2 ≤ 300 mm Hg or SpO2 < 90%
on room air, or other clinical evidence of hypoxemia
- Bilateral infiltrates on frontal chest radiograph
- No evidence of left atrial hypertension as the sole
explanation for the clinical findings
2) No pre-existing ALI before transfusion
3) Onset during or within 6 hours of transfusion
4) No temporal relationship to an alternative
risk factor for ALI
TACO
New onset or exacerbation of three or more
of the following within 6 hours of transfusion:
- Acute respiratory distress (dyspnea, cough, orthopnea)
- Increased brain natriuretic peptide (BNP)
- Increased central venous pressure (CVP)
- Evidence of left heart failure
- Evidence of positive fluid balance
- Radiographic evidence of pulmonary edema
Delayed emergence
Drug Effects
- Residual anesthetic such as volatile anesthetic or propofol
- Residual neuromuscular blockade
o Assess with peripheral nerve stimulator
o Pseudocholinesterase deficiency with succinylcholine could be an explanation for prolonged paralysis after adequate time for reversal has been given.
- Opioids
o Trial of antagonism with naloxone
- Benzodiazepines
o Trial of antagonism with flumazenil may be considered
- Excess cholinergics such as scopolamine
o Trial of antagonism with physostigmine
- Alcohol or other drug intoxication
Metabolic Derangements
- Hypoglycemia
o Assess blood glucose level
- Hypoxemia and/or hypercarbia
o Assess vital signs (E) including pulse oximetry and end tidal CO2.
o Obtain arterial blood gas. Continue mechanical ventilation until corrected.
- Hypothermia/hyperthermia
o Assess vital signs including temperature
- Acidosis
o Obtain arterial blood gas and correct underlying disorder as necessary
- Hyponatremia (e.g. after urologic surgery)
o Obtain metabolic panel and correct as necessary
Neurologic Disorder
- New stroke, either ischemic or hemorrhagic
o Perform full neurologic exam if able (pupils, cranial nerves, reflexes, withdrawal to pain)
o Consider CT scan or MRI scan if adequate concern or suspicion
- Seizure or post-ictal state
- Increased intracranial pressure
Level of spinal block (things that affect)
Drug dosage, drug baricity, and patient positioning
Recall risk factors
female sex, age (younger adults, but not children), obesity, anesthetist seniority (junior trainees), previous awareness, out-of-hours operating, emergencies, type of surgery (obstetric, cardiac, thoracic), and use of neuromuscular blockade.
Aspiration with LMA
increasing FiO2 to 100%, deepening anesthesia (to facilitate further interventions), and placing the patient in a head-down position. The latter helps limit pulmonary contamination by using gravity to help prevent the aspirate from reaching further into the lungs, and may also facilitate suctioning (see below). Most of the time, suctioning should be performed and the severity of aspiration should be assessed using fiberoptic
Hyponatremia
- excess H2O relative to sodium.
- emesis, weaknessm mental status changes, seizures and coma
- replace at 0.5 mEQ/L/H to avoid centril pntine myelinolysis (2 if symptomatic)
- hypovomelmic hyponatremia: NS infusion
- SIADH: fluid restriction
- Hypervolemic: loops diuretics
Hypernatremia
treatment involves calculating free water defecit
(( [NA]- [target Na]) /[target]) X TBW
Carbonic anhydrase inhibitors
- blocl H+ + HCO3- + H2Co3 H20 + Co2.
- this causes increase of H+ in tubule which is reabsorbed in exchange for Na
- Na is reabsorbed distally so not too effecting
- used to improve excretion of acidic substances through urine alkalization
- acetazolamide (altitude sickness), methazolamide
Osmotic Diuretics
- mannitol
- enhances RBF and dilutes the tubular filtrate to prevent tubular obstructon.
- effective ppx against acute renal failure to to acute tubular necrosis.
- decrease IOP and ICP
Loop diuretics
furosemide, ethcrynic acid (use with sulfa allergy), bumetanide and tosemide
- inhibit Na and Cl reabsorption at the Na-K-2CL channel in thick ascending limb of the loop of Henle
Thiazide diuretics
HCTZ, metolazone, chlorthalidonem indaptamide and quinethazone
-Inhibit Na-CL channels in the distal convuluted tubule
Potassium sparing diuretics
- Aldosterone inhibitors: spironolactone and epleremone
- Inhibits the opening of sodium channels in collecting duct: amiloride, triamterene
FEnoldopam
Selective DA1 receptor agonitst
- systemic arteriolar vasodilation leading to afterload reduction
0. 1 mcg/kg/min
Neostigmine for Sux reversal
.02 mg/kg when a phase II block is present
clears 2 hours before surgery
Ingestion of water 2 hours prior to a procedure results in smaller gastric volumes and higher gastric pH when compared with those who ingested > 4 hours prior.
partial laryngospasm treatment
removal of offending agents (if they are present such as secretions), jaw thrust at the retromandibular notch with 15-20 cm H2O of CPAP and 100% oxygen
- can deepen if needed or paralyze
retained epidural catheter fragment
CT
Bioavalability of midaz
intravenous > intramuscular > intranasal > rectal > oral
Doxorubicin
severe cardiac toxicity but can also cause pulmonary infiltrates, myelotoxicity, and toxicity to the gastrointestinal, hepatic, and renal systems
Best test for compartment syndrome in PACU
Needle measurement of pressures
O2 in setting of COPD
increased V/Q mismatch
methemoglobinemia treatment
methylene blue
-if pt has G6PD defeciency: ascorbic acid (vitmain C)
drug that can increase digoxin effect and toxicity
Furosemide
- hypokalmeia potentiates digoxin
traumatic brain injury (TBI), increased urine output, and hypotension
Vasopressin
Benzos as muscle relaxants
Central GABA receptors
Chronic barbiturate use
increases cytochrome P450 reducing duration of action of drugs metabolized by p450
CPDA
CPDA-1 anticoagulant allows PRBC and whole blood storage for up to 35 days
- Citrate is the anticoagulant (binds calcium necessary for clot formation)
- Phosphate is incorporated for cellular function and ATP production
- Dextrose is the nutrition source for glycolysis
- Adenine is incorporated for ATP production
Unfractionated heparin
- accelrated the rate of anticoagulant activity by bining to its cofactor antithrombin III (antithrobin)
- usually affects intrinisic pathway but at higher lievel and inhibit extrinsic
- Reversed with protamine sulfate
- riks: HIT and osteoporosis
Heparin induced thrombocytopenia
- two types
- 1: mild thrombocytopenia: recovers in a few days even in the site of heperin
- 2: progressive thrombocytopenia; bleeding.
LMWH
- improved specificity for factor Xa (than heparin)
- similar but less risky side effect profile with heparin
- dont use in risk of bleeding because protamine doesnt reverse
Fondaparinux
- synthetic analog of the pentasaccharide sequence for AT binding
- Xa specific antibody
Warfarin
- inhibits vitamin K dependent coag factors ( 2,7,9,10 and protein C and S
- C and S are anticoagulant inhibitors ( initial prothrobic situation); bridge with heparin
- INR 2-3
- if protein C and S deficiency can have necrosis due to thrombus in skin initially
Direct thrombin inhibitors
lepirudin, bivalrudin, argatroban,
- argatroban; metabolized in liver
- rudins excreted by kidney
Antithrombin drugs
- plasmin (pro drug plasminogen) is the primary catalyst for fibrinolysis.
- drugs activate plasminogen or plasmin
- endogenously plasmin and alpha-2 antiplasm regulate anti thrombic or pro thrombic state
PLasminogen activators
- streptokinase, urokinase
- recombinant: alteplase, tenecteplase, reteplase
direct activing thrombolutic agents : tissue plasminogen activator (t-PA)
Closed circuit contraidications
ETOH, DKA, SEVO use, heavy smoker, malnutrition, cirrhosis
greatest decrease in FRC
60 percent to supine or Tburg > -30
Morphine enzyme
OPRM mutation renders morphine less potent
MC1R mutation cause increased potency
2C19
metabolism of PPI and some antidepressants
2C9
phenytoin, warfarin and ibuprofen
2D6
codeine, beta-blockers, some antiarrhythmics, diltiazem, and tramadol
Decreases in low lumbar/ thorasic epidurals
cough 50%
Peak expiratory pressure 40%
FEV1 10%-20%
Nausea after a high spinal
- Risk factors include high block (above T5), hypotension, opioid administration, and a history of motion sickness
- Unopposed parasympathetic (vagal) activity after sympathetic blockade causes increased peristalsis of the gastrointestinal tract, which can lead to nausea and is the primary mechanism behind nausea after spinal blockade
- treat with atropine, glycopyrrolate
Hyperthyroidism
General: weight loss, heat intolerance and warm, moist skin
Cardiovascular: tachycardia, atrial fibrillation and congestive heart failure
Neurologic: nervousness, tremor, hyperactive reflexes
Gastrointestinal: diarrhea
Musculoskeletal: muscle weakness
Hematologic: anemia, thrombocytopenia