Pharm Response To Bypass Flashcards
Drugs affected by altered hepatic flow on CPB
Fentanyl
Propofol
Type of drug that sticks to coated surface of tubing
Lipopholic drugs
4 things to ensure before administering drugs
Have surgeons permission or written protocol
Patient is not allergic to drug
Have correct drug and dosage
Check for expiration date, precipitates, and sterility
8 drugs always in drug box
Heparin Neo-Synephrine NaHCO3 Lidocaine MgSO4 Calcium Potassium Mannitol
Concentration of heparin in mg
100units=1mg
Drugs affected by lungs being remove from circulation on CPB
Valium
Propofol
Opioids
Action of heparin
Inhibits coagulation by Potentiation ATIII and inhibiting factors 9&11
Half life of heparin at CPB doses
2 or more hours
4 side effects of heparin
Activate tPA and platelets
Bolus decreases SVR by 10-20%
Anaphylaxis rarely
HIT and HITT
Heparin dosing
Loading dose: 300-450 units/kg (distributes in plasma so rarely exceeds 35000-40,000units)
Priming soln: same conc. as patients blood
Most vials will be 1000units/mL
Action of Neo-Synephrine
Alpha-1 agonist causing vasoconstriction in arterioles
Duration: less than 5 min
Dosing of Neo-Synephrine
IV bolus: 100, 200, or 400ug/mL
IV infusion: 10 or 15mg in 250mL vial (40-60ug/mL)
Action of NaHCO3
IV injection as electrolyte replenisher and alkalizer
Treats Hyperkalemia
Dosing of NaHCO3
1 amp= 50mEq
Dose (mEq)= 0.3weightBE
Hyperkalemia: adults 50mEq, Peds 1-2mEq/kg
Action and duration of lidocaine
Reduces cell membrane permeability to Na and K, increasing stimulation threshold in ventricles
Duration: 15-30min post bolus
Lidocaine dosing
IV bolus: 1-2mg/kg
XC removal: 100-200mg
Don’t exceed 300mg/hr
Action of MgSO4
Controls transmembrane electrolytes and energy metabolism
Causes for hypomagnesia on CPB
Poor preop health
Albumin administration
Citrate blood product administration
Hypomagnesia can cause arrhythmias
MgSO4 dosing
2-2.5g bolus
XC removal: 2-4g with Lidocaine
Concentration: 0.5g/mL
Action of calcium chloride
Myocardial contractility, blood clotting, neurotransmission, and muscle contraction
Levels drop on CPB: must replenish if give citrate blood products
CaCl2 dosing
Concentration: 100mg/mL
Given post XC
Hyperkalemia: adults 0.5-1g CaCl2, Peds 20mg/kg Ca Gluconate
Potassium chloride action
Normal cardiac contractions
KCl dosing
CPG: 15-30mmol/L
Hypokalemia dose= weight0.3K deficit
Concentration: 2mEq/mL
GIVE SLOWLY
Action of mannitol
Osmotic diuretic prevents reabsorption in proximal tubule
Free radical scavenger
Mannitol dosing
On CPB: 0.5-1g/kg
12.5g vials
10 drugs that may be in drug box
THAM Amicar Trasylol Thrombate III Benadryl Solumedrol Dextrose Albumin Insulin Forane
Action of THAM (Tromethamine)
Combines with H ions to form Bicarb, causing alkaline environment (buffer)
THAM dosing
Concentration: 3.6g/100mL (30mEq)
Dose (mL)= weightBE1.1
Action of Amicar
Inhibits plasminogen activators to prevent conversion to plasmin
Reduces bleeding caused by fibrinolysis
Dosing of Amicar
Loading dose: 5g IV
Action of Trasylol
Inhibits fibrinolysis and turnover of coagulation factors (serine protease inhibitor)
Trasylol dosing
Test dose: 1mL 10min before loading
Loading dose: 200mL (280mg) over 20-30min
Prime dose: 200mL
May artificially prolong ACT results
Action of Thrombate III
Inactivated thrombin and factors 9,10,11,&12 which results in inhibited coagulation
Enhances heparin if have ATIII deficiency
Thrombate III dosing
Dose= (desired-actual ATIII)*kg/1.4
Each vial has 500 IU
Use within 3 hours of reconstitution
Action of Benadryl
Antihistamine, sedative, antiemetic, anticholinergic
Benadryl dose
10-50mg
Action of Solumedrol
Intermediate acting glucocorticoid used to combat inflammation, often during circ arrest
Can cause hyperglycemia
Dose of Solumedrol
125mg-1g
Sterile powder mixed with diluent, must be used within 48 hours of mixing
3 inhalation anesthetics
Forane
Isoflurane
Sevoflurane
Action of inhalation anesthetics
Ethers that modulate GABA-a receptor used for induction and maintenance of anesthesia
Potent vasodilators
Short term effects of Forane
Liver and kidney disease Headache Irritability Fatigue Nausea Drowsiness Compromised performance
Long term affects of Forane
Miscarriage (in exposed worker AND spouses)
Genetic damage
Cancer
Action of Albumin
Concentration of proteins derived from human blood
Increases plasma volume or serum albumin levels
Don’t use on Jehovah’s Witness!
Albumin dosing
Concentrations: 5, 20, or 25% (25% contains 250mg/1000mL)
Increases circulating volume 3.5x volume injected
Prime: 12.5-25g
Give when serum albumin
Action of insulin
Stimulate glucose utilization by muscle and fat and acts on liver to inhibit glycogenolysis and gluconeogenesis
Insulin dosing
Target glucose range: 110-180mg/dL 100units/mL 10-20 units IV *Never shale vial!! Roll in hands to mix* Use 1mL syringe
Insulin dosing for Hyperkalemia
Adults: 25g Dextrose+ 10units insulin
Peds: 1-2g/kg Dextrose + 0.3units insulin per gram Dextrose
Action of Dextrose D-50
Concentrated carbohydrate to fix hypoglycemia
Dose of Dextrose D-50
10-25g
