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
Alfentanil
- pKa of 6.5 meaning that it is primarily non-ionized at physiologic pH (approximately 90%) which allows it to move across membranes very rapidly providing a very fast onset and offset with a bolus dose
- Compared to fentanyl: alfentanil has 4x faster onset, is 1/4th as potent, and lasts about 1/4th the duration. (smaller volume of distribution)
Foods related to latex allergy
avocados, bananas, chestnuts, kiwi fruit, papayas, potatoes, and tomatoes.
LMA intubation size
Unique or classic: 3) 6, 4)6, 5) 7
Ambu Aura 3)7.5, 4) 7.5, 5)8
Proseal 3) 5, 4)5, 6)6
I get 3) 6, 4)7, 5)8
sympathetic cardiac adernergic innervation
originates from T1-T4 and is associated with α1, β1, and β2 adrenergic receptors
- The right stellate ganglion tends to exert more effect on heart rate. The left stellate ganglion has a stronger effect on mean arterial pressure and contractility.
- A left stellate ganglion block can be performed to reduce the risk of arrhythmias associated with long QT syndrome.
Neuromuscular monitoring sites
After laryngeal muscles and diaphragm, the corrugator supercilii (eyebrow movement) is the most resistant to neuromuscular blockade and most closely resembles the abdominal and laryngeal muscles. The adductor pollicis is more sensitive to neuromuscular blockade and is the best choice to monitor for extubating conditions. The flexor hallucis (big toe flexion) and orbicularis oculi (eyelid movement) correlate more closely with the adductor pollicis.
emergence reaction with ketamine risk factors
Age: Adult patients are more likely to report a high incidence compared to pediatrics.
Gender: Females are more likely than males.
Dosage: Larger doses with rapid administration increase the risk.
Psychological Susceptibility: Certain personalities types are at an increased risk; those who tend to dream at home and those who score high on the Eysenck Personality Questionnaire (extrovert, neurotic) tend to have a higher risk.
Concurrent Medications: Multiple medications increase the incidence although administering a benzodiazepine prior to administration of ketamine helps decrease the risk.
Strong ion difference
The concept of SID proposes that plasma pH is determined by three independent factors: PCO2, SID, and Atot. The latter (Atot) represents the total plasma concentration of nonvolatile buffers (e.g., albumin, globulins, and inorganic phosphate). Strong ion difference represents the difference between the charge of plasma strong cations (sodium, potassium, calcium, magnesium) and anions (chloride and other strong anions (A-) such as lactate, sulfate, ketoacids, and nonesterified fatty acids).
SID = ( [Na+] + [K+] + [Ca2+] + [Mg2+] ) - ( [Cl-] + [A-] ) ≈ 40-44 mEq/L
IM meds
Cardiovascular medications that can be given intramuscularly include, but are not limited to atropine, glycopyrrolate, ephedrine, epinephrine, phenylephrine, and hydralazine.
Longest antithrombic drug
Ticlodipine 10-14 days
ASA 7 days
Transdermal fentanyl patch
onset in 6-8 hours
peak at 30 hours
Respiratory calculations
- acute respiratory acidosis: pH decrease of 0.05 and a HCO3- increase of 1 mEq/L per acute 10 mm Hg increase in PaCO2
- chronic respiratory acidosis: pH nearly normalizes and HCO3- concentrations increase 4 to 5 mEq/L per 10 mm Hg sustained increase in PaCO2
- acute respiratory alkalosis; pH increase of 0.10 and a HCO3- decrease of 2 mEq/L per acute 10 mm Hg decrease in PaCO2.
- chronic alkalosis, pH nearly normalizes and HCO3- decreases 5 to 6 mEq/L per 10 mm Hg sustained decrease in PaCO2
Physiologic changes with PEEP
PEEP application raises intrathoracic pressure, right ventricular afterload, decreases preload and can cause hypotension in the normovolemic or hypovolemic patient without heart failure. In patients with systolic heart failure, preload is excessive, thus PEEP preload effects are minimized but afterload is decreased with resultant improvement in cardiac output and a decrease in LVEDP
Ankylosis spondylitis
- difficult mask, intubation,
- increase risk of epidural hematoma
Methadone and QT
- prolongation
- same as ciprofloxacin
P2Y1 blockers
- block the activation of GIIb/IIIa
- ticlopidine
- clopidogrel, prasugrel,
- cangrelor, ticagrelor
Dipyridamole
increases levels of cAMP in platelets
- reduces intracellular levels of calcium
- inhibits platelet activation and aggregation
GIIa/IIIb blockers
-abciximab, eptifibatide, tirofiban
Amiodarone side effects
bradycardia, hypotension, hypothyroidism, life-threatening hyperthyroid storm, pulmonary toxicity (with a pulmonary fibrosis appearance), prolonged QT interval, and elevated liver function markers
Volume of distribution factors
The volume of distribution is the total drug within the body divided by the drug plasma concentration. It is directly proportional to the unbound drug in the plasma and inversely proportional to the unbound drug in the tissue. As such, drugs that are lipophilic have a higher Vd than drugs that are hydrophilic. Also, having greater tissue binding will decrease the unbound proportion in the tissue, thus increasing the volume of distribution.
-Volume of Distribution (Vd) = Drug dose / Plasma concentration
variable INTRAthoracic airway obstruction
, distal tracheal tumor or mediastinal mass
EXTRAthoracic airway obstruction
vocal cord paralysis or dysfunction, proximal tracheal tumor, glottic strictures
fixed upper airway obstruction or fixed large airway obstruction
foreign body, tracheal stenosis, large airway tumor
ACEi contraindications
RAS, pregnancy, and patients with history of angioedema (whether related to ACE-I or not)
workup for chronic dantrolene use
LFTs
Tramadol
weak mu receptor agonist
Opioid receptors
Delta receptor: analgesia, antidepressant, physical dependence
Kappa receptor: analgesia, dysphoria, miosis, sedation
Mu receptor: analgesia, physical dependence, respiratory depression, miosis, euphoria, decreased gastrointestinal motility
Cardioselective B blockers
BEAM” (Bisoprolol, Esmolol, Atenolol, and Metoprolol)
Propranolol
non selective Beta blocker
Labetalol
Think “laβetαlol.” The ratio of relative α:β potency of IV labetalol is approximately 1:7 whereas PO labetalol is 1:3.
Beta blocker that undergoes renal metabolism
Atenolol (think ATNolol)
Vassopressin
Vasopressin stimulates water retention and peripheral vasoconstriction while improving MAP and cerebral and coronary perfusion. Vasopressin dramatically increases SVR and afterload which potentially reduces CO.
- mild decrease in platelet concentration and an increase in platelet aggregation
Ischemic Optic neuropathy
sudden onset, painless vision loss most typically following lengthy spine surgeries in the prone position
Volatile that decreased BP by decreasing CO
Halothane
Side effects of corticosteroids
leukocytosis, increased hemoglobin, hyperglycemia, hypokalemia, mild hypernatremia, alkalosis, increased urinary uric acid, and increased urinary calcium
Transtracheal injection of LA
blocks RLN
Liver disease derangements
reduces factors II, VII, IX, X, as well as V, XI, and thrombin. Protein C is also reduced. Factor VIII and vWF are increased in patients with liver disease as they are produced extra-hepatically.
Coagulation management in liver disease
1) Maintain platelet count at 50-60; in high-risk surgery maintain >100
2) Keep fibrinogen >100
3) Transfuse to maintain Hgb > 7
4) Do not give FFP prophylactically or chase INR levels
- Increased INR in these patients does not necessarily reflect risk of bleeding
- If FFP is to be given, dose is 20-40 mL/kg
IO site
sternum (manubrium), proximal humerus, proximal tibia, and distal tibia.
Sodium in 5% albumin
145 +/- 15
Decreased BP with reduction in afterload with no decrease in preload
Nicardipine is primarily an ARTERIOLAR vasodilator and decreases left ventricular afterload and systemic vascular resistance with minimal effect upon preload. It is a short acting (t1/2 = 3-14 minutes) dihydropyridine calcium channel blocker that does not significantly decrease cardiac inotropy and may actually cause reflex tachycardia
Drug resembles brain natriuretic peptide and causes vasodilation, diuresis, and natriuresis?
Nesiritide
Overlap of IJ and CCA
Excessive rotation to the contralateral side of the head
NMB in cirrhosis
Intubating doses of neuromuscular blocking drugs are increased in cirrhosis because of the increase in volume of distribution. Maintenance doses of hepatically metabolized and/or cleared drugs should be reduced and neuromuscular function carefully monitored as duration of action is prolonged.
Lorazepam degradation
glucuronidation metabolism in the liver without any phase I metabolism
p50 by age
P50 is lowest in newborns (18 mm Hg) and is highest in children over 12 months of age (30 mm Hg). After 10 years of age, P50 decreases to adult level (27 mm Hg).
Least amount of reflection on US
High water content: blood effusions, cysts
smallest increase in dosage of NDNMBs in setting of burn
Mivacurium: This is degraded by pseudocholinesterase. Therefor the lack of psuedocholisterase helps offset the increase in non junctional receptors
- still a small increase but not as much required as others
Postoperative hepatic dysfunction
- uncommon without preexisting liver damage
- mild type ( nausea, lethargy, fever
- immune type ( rare, widespread hepatic necrosis)
- Halothane no longer used
- Des: has degradation product TFA (trifloroacetic acid) which can cause liver damage
- Sevo: hexafluoroisopropanol (HFIP), which does not accumulate and rapidly undergoes phase II biotransformation
Haldane effect
oxygenation of hemoglobin lowers the affinity of hemoglobin for carbon dioxide
Activation of nociception
Peripheral: prostaglandins, neuropeptides (e.g. substance P, calcitonin gene-related peptide), glutamate, bradykinin, H+, ATP, and proinflammatory cytokines (e.g., TNF-α, Interleukin-1β)
Spinal cord inhibition: opioids, GABA or glycine
Prevention of bronchospasm
albuterol, 3 day course of steroids, topical lidocaine
Changes in CO affect which volatile the most with speed of induction
- biggest increase/decrease with the more soluble drugs
Heparin and epidural
check platelets (>100), hold heparin for 4-6 hours
R wave
1) Right ventricular hypertrophy
2) Posterior wall MI
3) Wolff-Parkinson-White syndrome
4) Muscular dystrophy
5) Right atrial enlargement
6) Right ventricular strain with ST-T wave abnormalities
Quick correction of elevated INR for emergent surgery
Prothrombin complex concentrate
Incompentant inspiratory valve
allows exhaled gas (containing CO2) to enter the inspiratory limb of the breathing circuit during expiration. Therefore, the CO2-containing gas is inspired by the patient during the following inspiration. This extends the expiratory alveolar plateau (phase 3-4 in Figure 1). A decrease in CO2 occurs after the extended plateau and represents sampling of CO2-free gas that arrived from further proximal in the inspiratory limb. Thus the inspiratory downstroke (phase 4-1 in Figure 1) is significantly blunted and the inspiratory phase is shortened.
ED95 meaning for NDNMB
the effective dose required to achieve 95% block of a single twitch in 50% of individuals
LMWH for epidural
- therapeutic: 24 hours, PPX: 12 hours (same restart if catheter)
- if catheter then only ppx and once daily after 12 hours
- remove catheter 12 hours after
- restart 4 hours after catheter removal
Hydroxylethyl starches
Hetastarches are traditionally associated with a higher risk of coagulopathies (platelet adhesion interference, reduced factor VIII:C and vWF levels, and PTT prolongation) than the newer, lower molecular weight tetrastarches.
-maximum daily doses of hetastarches (~20 mL/kg) are generally less than tetrastarches (~50 mL/kg).
Mortality rate for drug abusers post treatment in residency
7-13%
lithotomy position
stretch injury to the sciatic nerve and compression injuries to nerves that pass beneath and through the inguinal ligament, including the obturator, femoral and lateral femoral cutaneous nerves. Also sciatic can get stretched
- does not affect proximal posterior thigh
Cyanide toxicity
- sodium nitroprusside (SNP)
- elevated mixed venous oxygen, SNP tachyphylaxis, metabolic acidosis, flushing
GABA receptors
Baclofen for GABAB and Anesthetics for GABAA.
onset of gastric pH meds
- antacids 5-20 mintutes
- H2 blockers 1 hour for oral, quicker for IV
- PPI 2-3 hours
Type and screen
determining the recipient’s ABO status (mixing recipient red cells with anti-A, anti-B, and anti-AB antibodies), Rh status (mixing recipient red cells with anti-D antibodies), and screening for unexpected antibody status (mixing recipient serum with known surface antigens on commercially supplied type O RBCs)
Type and match
involves mixing recipient serum with donor red blood cells to examine for any incompatibilities that were not screened out as well as setting aside the desired number of blood products for potential transfusion.
transfusion-related immunomodulation (TRIM)
- Homologous (allogeneic) blood transfusion exerts a nonspecific immune effect on the recipient
- both pro-inflammatory and immunosuppressive effects
- The only established clinical effect of TRIM is the enhanced survival of renal allografts.
Myoclonus with induction
Etomidate, ketamine, and methohexital are associated with myoclonus. Propofol, although less common, is also associated with myoclonic movements. Midazolam has not been associated with myoclonus.
Hetastarch
inhibits agonist-induced expression of glycoprotein IIb-IIIa complex availability on platelets
- A coagulation effect of hetastarch administration is direct movement into fibrin clots.
- A coagulation effect of hetastarch administration is a reduction in factor VIII and von Willebrand factor.
- A coagulation effect of hetastarch administration is a dilutional effect
preop liver eval
- Plasma albumin has a half-life of nearly 3 weeks.
- Normal AST and ALT can occur in liver failure when there are no more hepatacytes to release enzymes
- 5′-nucleotidase is a marker of cholestasis, along with γ-Glutamyl transpeptidase and alkaline phosphatase. However, alkaline phosphatase lacks specificity for hepatobiliary disease and may be derived from bone or other sources
most common complication of jet ventaliation
- Hypercarbia
- Other important complications include impaired respiratory ciliary function, hypoxia, and loss of the airway. Rarely, subcutaneous emphysema, pneumothorax, and pneumomediastinum can result from barotrauma while necrotizing tracheobronchitis can occur from prolonged use.
Mapleson
All Dogs Can Bite (spontaneously): A > D > C > B
Dead Bodies Can’t Argue (controlled): D > B > C > A
discharge from Phase 1 (or skip completely)
- modified aldrete score
- BP, O2, movement, responsiveness, breathing
Meds causing hyperkalemia
digitalis, heparin, mannitol, pentamide, sux, traimterene, trimethoprim, ACEi, ARBs, Beta blockers, NSAIDS, K sparing diuretics
Haldane vrs Bohr
he Bohr and Haldane effects are complementary principles that help explain the efficient delivery of O2 to the tissue and CO2 to the lungs. The Bohr effect states that in areas of high CO2, the hemoglobin has less affinity for O2 which is more readily released for consumption by the tissues. The Haldane effect states that deoxygenated hemoglobin has a higher affinity for CO2. Once the deoxygenated hemoglobin reaches the lungs, the high O2 concentration decreases this affinity and the CO2 is released.
Infants have a increased volatile anesthetic take up
Increased MV to FRC ratio
Epidural and ileus
The autonomic nervous system plays a large role in regulating gastrointestinal motility. Tonic inhibitory sympathetic control (T6-L2) predominates, but parasympathetic activation increases contractility. Therefore, sympathectomy induced by epidural or spinal analgesia results in increased gut motility (B), especially those involving epidural catheter placement at T12 or higher
Nerve stimulation in paralyzed nerves
The proliferation of extrajunctional acetylcholine receptors in muscle in paralyzed limbs can lead to an increased response (T4:T1) to peripheral nerve stimulation following non depolarizing neuromuscular blockade compared to a normal non paralyzed limb in the same patient
Strong predictors of difficult intubation in obesity
- Neck thickness, Mallpati 3,4 and presence of OSA
MAP =
MAP = CO X SVR
SVR=
SVR = [80 * (MAP – RAP)] ÷ CO
PVR=
PVR = [80 * (MPAP – PAOP)] ÷ CO
ACE and bradykinin
- Angiotensin converting enzyme catalyzes the degradation of bradykinin. Under normal conditions, bradykinin promotes vasodilation by increasing production of arachidonic acid metabolites and nitric oxide. ACE inhibition will increase levels of bradykinin, promoting its effect in reducing blood pressure.
- Bradykinin also affects vascular endothelium by increasing production of arachidonic acid metabolites and nitric oxide promoting vasodilation.
Respiratory alkalosis causes
Central : stroke, aspirin overdose, anxiety, pain, and progesterone
pulmonary causes: pulmonary embolism, pneumonia, or asthma
Temp correction
Blood pH and the solubilities of gases in blood are inversely related to temperature while the partial pressures of gases are directly related to temperature. Accordingly, when arterial blood gas values are corrected to a colder temperature, PaO2 and PaCO2 decrease while pH increases.
RAAS onset
20 minutes
Brachial artery A line
Brachial artery catheterization is low risk and can be used for long-term monitoring. Potential complications include thrombosis (highest), infection (way less than femoral), and median nerve injury.
Respiratory quotient
RQ is the ratio of column of carbon dioxide eliminated to oxygen consumed in steady state
carbs = 1
Fats = 0.7
Proteins =0.82
R->L shunt vs changes in CO for volatiles
- Shunts most affect those with low blood gas coefficients
- CO affects those with high
Pre renal
BUN:Cr ratio >20
FENa <1%
Urine sodium < 10 mEq
Urine Osms > 500
MI prior to surgery
old > 30 days
acute < 7
recent 7-30
* old is not a risk factor; can proceed to surgery without workup
respiratory factor that increases with epidural in pregnancy
- vital capacity
decreases: RR, atalectasis - MV stays the same
associations with spinal anesthesia
- decreased hearing
- increase GI secretions
- hypothermia
- increased ventilatory response to hypercapnia
- postdural puncture headache
Opioid metabolites
Drug Analgesic Neuroexcitatory
Hydromorphone-3-glucuronide Inactive Present
Morphine-6-glucuronide Active Present
Normeperidine Inactive Present
Oxymorphone Active Absent
hold ASA for:
intracranial neurosurgical procedures, middle ear surgery, posterior eye surgery, intramedullary spine surgery, and possibly prostate surgery
Filling vaporizers wrong
When a vaporizer calibrated for a higher vapor pressure (e.g., isoflurane at 240 mm Hg) is filled with a volatile agent of a lower vapor pressure (e.g., sevoflurane at 160 mm Hg) less output or a lower concentration is delivered. The converse is true when isoflurane is placed in a sevoflurane vaporizer.
Rapid and reliable confirmation of proper intubation during CPR
Esophageal detector device
SSRI affecting hydrocodone
Selective serotonin reuptake inhibitors (SSRIs), specifically fluoxetine and paroxetine, significantly inhibit CYP2D6 and slow the conversion of hydrocodone to hydromorphone within the liver.
Citrate intoxication
- low calcium and magnesium
- myocardial depression
- coagulopathy
Roc for precurization
10% ED95 dose (.03 mg/kg)
IE PPx
Prosthetic cardiac valves
Previous infective endocarditis
Valvular heart disease following cardiac transplantation
Unrepaired cyanotic congenital heart disease (CHD), including palliative shunts and conduits
Repaired CHD with prosthetic materials/device(s) placed in first 6 months following the procedure
Repaired CHD with residual defects
When:
Dental procedures with manipulation of gingival tissue or perforation of oral mucosa
Respiratory tract procedures involving incision or biopsy of mucosa (e.g., bronchoscopy with biopsy, lung resection)
Patients with infected skin, skin sutures, or musculoskeletal tissue
Side effect of bicarb administration
Sodium bicarbonate administration is associated with transient increases in PaCO2, EtCO2, and intracranial pressure. Administration causes transient decreases in serum calcium and potassium. Sodium bicarbonate can also cause hypotension due to hypocalcemia, ventricular depressant effects, and redistribution of blood to the pulmonary vasculature.
-increased hemoglobin affinity for oxygen. Sodium bicarbonate administration is also associated with intracranial hemorrhage, especially with rapid administration in infants, and increased lactate production.
Contraindications to ketamine
- Increased ICP with spontaneous ventilation
- Intracranial mass lesion with spontaneous ventilation
- Open eye injury or other ophthalmologic disorder (increased IOP)
- Ischemic heart disease (as sole anesthetic agent)
- Vascular aneurysms (as sole anesthetic agent)
- Psychiatric disease such as schizophrenia
Sudden drop in ETCO2
cardiovascular collapse, massive VAE, large PE, esophageal intubation, circuit or sampling line disconnection, or a dislodged/kinked endotracheal tube.
PCA age
> 6
opioid PCA for pain control and decreased adverse outcomes
IV PCA with no basal rate
LMWH
The effect of small fragments in LMWH are widespread: reduced binding with thrombin, proteins, macrophages, and platelets. This leads to an increased anti-Xa:IIa ratio, more predictable anticoagulant response, renal clearance, and decreased heparin-dependent antibodies
Complications of autologous blood donation
Infection from improper storage and clerical error are two important causes of reactions to autologous blood transfusions. Hemolytic and nonhemolytic transfusion reactions are extremely rare as autologous blood should not contain non-self antigens
Increase in PaCO2 and ET CO2 gradient
-decrease in CO
FENa
FENa = [(PCr x UNa ) / (PNa x UCr)] x 100
hypoalbuminemia affects which drugs
Hypoalbuminemia will increase the free fraction of benzodiazepines, thus lower doses are required (B) to achieve the same effect relative to healthy patients.
Releive opioid induced biliary colic
-naloxone, papaverine, atropine
Benefit of epinephrine during cardiac arrest
Alpha 1
Arteriol O2 content
Arterial oxygen content (CaO2) = (Hgb * 1.36 * SaO2) + (0.003 * PaO2)
nitroprusside toxicity mechanism
1) Cyanmethoglobin
2) Cytochrome oxidase impairment
3) Thiocyanate production
Started on Beta Blocker
patients with 3 or more coronary artery disease risk factors with high risk surgery
Class recommendations
Class 1 – benefit is greater than risk and recommendation should be followed
Class 2a – benefit greater than risk and it is reasonable to perform therapy
Class 2b - benefit is slightly better or equal to risk and treatment should be considered
Class 3 – no benefit and may be harmful
largest proportion of closed claims for death or brain damage
non-respiratory events
inhibitors of HPV
-Direct: hypocarbia, vasodilating drugs, infection, metabolic alkalemia, and volatile anesthetics >1 MAC. —Indirect inhibitors of HPV include: hypervolemia, vasoconstricting drugs, hypothermia, thromboembolism, and a large hypoxic lung segment.
post HD effects
The semipermeable membrane used in HD permits only small molecules including water, electrolytes, minerals, and salts to cross according to their concentration gradients. The composition of the dialysate determines which substances move from blood to the dialysate and vice versa
-serum protein concentrations usually increase following HD due to a concentrating effect.
nerve sensitivity to LA
Differential blockade with local anesthetics results in sympathetic blockade first, followed by pain/sensory blockade, then motor blockade last. This is (at least in part) explained by differential susceptibility of nerve fibers to local anesthetics being A-delta, A-gamma > lA-alpha, A-beta > C
FRC and closing capacity nmonics
Causes of low FRC are PANGOS: Pregnancy, Ascites, Neonates, General anesthesia, Obesity, Supine position.
Factors that increase closing capacity are ACLS-SO: Age, Chronic bronchitis, LV failure, Smoking, Surgery, Obesity.
Fresh Gas flow with Mapelson
MV for A, 2-3 MV for DEF
