1. Treating Hemodynamic Disturbances and Threats to Tissue Oxygenation: A Review of Commonly Used PIC/NIC Medications Julie Warren RN, MSN, CCRN Pediatric CNS 4/2013-Current

2. Intravenous Infusion Guidelines
Most hemodynamic drugs have a rapid onset and are almost all given intravenously
Understand how long it will take for new dose to clear IV tubing containing an old dose: Don’t “treat” the line, treat the patient!

3. Alteration in the Autonomic Nervous System Responses
Contractile state = inotropy
Heart rate = chronotropy
Speed of conduction = dromotropy

4. Inotropes
An increased intracellular calcium concentration is the central cellular event that enhances contractility of the myocardium
Inotropes work in one of two ways:
Stimulate receptors to increase cAMP (cyclic adenosine monophosphate) which ultimately increases intracellular calcium
Inhibit phosphodiesterase (PDE) which then increases cAMP
Digitalis glycosides also enhance contractility but don’t use the cAMP “route”

5. Increasing Cardiac Strength
Use of inotropes and preload reducers

6. Dopamine: Dose varies based on intent: Primary side effects:
0.5-2 mcg/kg/min: renal perfusion/diuresis
2-5 mcg/kg/min: increased contractility and C.O. (little HR inc)
5-6 mcg/kg/min: HR and BP increase plus increased C.O.
10-20 mcg/kg/min: increased SVR/BP and HR
Primary side effects:
tachycardia
increased myocardial oxygen consumption (MVO2)

7. Dobutamine Improves contractility followed by  CVP,  SVR,  PVR
Dose:
2-5 mcg/kg/min to start
Maximum effects at mcg/kg/min
Max dose not known
Primary side effects:
tachycardia
increased myocardial oxygen consumption (MVO2)
potential hypotension
arrhythmias

8. Epinephrine: Dose varies based on intent: Primary side effects:
mcg/kg/min: Improves contractility and C.O. through peripheral vasodilation, HR,
SVR,  PVR
0.01-1mcg/kg/min: for asystole or pulseless arrest
> 0.3 mcg/kg/min: SVR and  BP; but vasoconstricts renal arteries
Primary side effects:
tachycardia
increased myocardial oxygen consumption (MVO2)
arrhythmias
hypertension
CNS excitation: restlessness/dread/fear

9. Norepinephrine
Its hemodynamic effects limit its use in pediatrics almost exclusively to treatment of septic shock; used to improve vascular tone after numerous boluses and other inotropes fail
Dose varies based on intent:
mcg/kg/min: Sharp  in SVR; improves contractility and C.O.if the increase in afterload can be tolerated
1-2 mcg/kg/min maximum
Primary side effects:
profound hypertension
ischemic injury of the extremities
CNS excitation: restlessness/dread/fear

10. Milrinone (Primacor) CO, SV,  SVR,  PVR,  CVP
A Bipyridine that works as a Phosphodiasterase (PDE) inhibitor/ “Inodilator”
Increases cAMP content for an inotropic effect with reduced O2 demand
CO, SV,  SVR,  PVR,  CVP
Mix in NS or 5% Dextrose
Dose:
Loading dose of 50 mcg/kg over 10 minutes
mcg/kg/min infusion
Side Effects: hypotension and arrhythmias

11. Review of Receptor Sites Increases contractility;
LOCATIONS
PRIMARY ACTION
ALPHA-ADRENERGIC
Alpha 1
Vascular smooth muscle
Arterioles and venules
Increases intracellular CA++; Muscle contraction; Constriction; Inhibits insulin secretion
Alpha 2
Presynaptic nerve terminals
Decreases cAMP; Inhibits norepi release; vasodilation; Negative chronotropy (HR)
BETA ADRENERGIC
Beta 1
Heart innervation:
SA node
AV node
Increases contractility;
Increases heart rate;
Increases automaticity;
Increases cAMP;
Enhances renin secretion
Beta 2
Pulmonary smooth muscle
Dilation; Relaxation
Increases cAMP; Bronchodilation; Enhanced glucagon secretion
DOPAMINERGIC
Vascular smooth muscle:
renal, coronary, mesenteric
Dilation

12. Effects of Commonly Used Inotropes
Agent
Dose
(mcg/kg/min)
Peripheral Vascular Effects
Alpha(+) = Constricting
Beta 2 (-) = Dilating
Cardiac Effects
Beta 1 (+) = ↑contractility
Beta 2 (+) = ↑contractility
Alpha (+)
Beta 2 (-) DA
Beta 1
Beta 2
Dopamine
2-5 2+
5-10
1-2+
> 10
2-3+
Dobutamine
2-10 1+ 3+
Epinephrine
Norepinephrine

13. Diuretics Furosemide Side Effects:
Dose 1-2 mg/kg q 6-12 hrs, given at max rate of 0.5 mg/kg/min; If larger doses required (>120 mg), the infusion rate should not exceed 4 mg/min
Can dilute to 1-2 mg/ml and give over mins
Continuous IV infusion:
0.05 mg/kg/hr titrated for clinical effectiveness
Side Effects:
Hypovolemia/hypotension
Hypokalemia/hyponatremia/hypochloremia
Ototoxicity
Metabolic alkalosis

14. Other Diuretics

15. Cautions with Diuretics
Used cautiously in patients who are hypotensive
due to potential to further reduce BP
Can cause fluid and electrolyte abnormalities
altered potassium and magnesium
dehydration/hypovolemia
Urine output is not always a reliable method of estimating preload reduction

16. Afterload Reducers

17. Nitroprusside (Nipride)
Balanced vasodilator: equal effects on venous and arterial circulation
If SVR is not elevated, SV and CO/CI decline and BP is reduced; HR increases as result
When SVR is high and contractility is depressed, the reduction in preload and afterload result in increased SV and CO/CI; the increase in SV is proportional to the decrease in SVR; HR declines and BP is unchanged
Dose: Given in 5% Dextrose- bag and tubing must be opaque or covered
0.5 mcg/kg/min starting dose
1.5-2 mcg/kg/min usually reduce SVR; highest dose is 10 mcg/kg/min
very rapid onset of action; effects stop 3 mins after infusion d/c’d
Side Effects:
byproduct of breakdown is NO and cyanide (toxic)
use only for short periods (< 72 hrs)
measure cyanide levels by measuring lactate levels
hypotension

18. Afterload Reducers The other key afterload reducer is Milrinone
Nitroglycerine is rarely used in children
Calcium channel blockers rarely used:
Nifedipine has been tried in hypertensive emergencies and to treat patients with hypertrophic cardiomyopathy (BP lowering effect in kids is not predictable however)
Diltiazem-has emerged as an effective agent for SVT and atrial fib/flutter
ACE inhibitors: Captopril/Enalopril
Also reduce preload

19. Other Key Drugs
Digoxin (increases contractility and has antiarrhythmic properties)
Antiarryhthmics
Adenosine (SVT)
Procainamide (SVT/JET/atrial ectopic tachycardia)
Lidocaine (Vtach/Vfib)
Amiodorone (Vtach/Vfib)
Esmolol (tachyarrhythmias)
Sotalol (refractory SVT/VT)
Triiodothyronine (T3) -increases CO/decreases SVR
Ca++ (increases contractility)
Nesiritide /Natrecor (diuretic/natriuretic/vasodilator)

20. Other Key Drugs Pulmonary Bed Vasodilators:
Oxygen
Prostaglandins (also dilates PDA)
iNO
Prostacyclins:
Epoprostenol (Flolan)
Endothelin Receptor Antagonists:
Bosentan (Tracleer)
Phosphodiesterase Inhibitors:
Sildenafil (Viagra) - oral
Pulmonary Bed Vasoconstrictors:
Nitrogen
CO2

21. Miscellaneous Drugs Insulin Infusions for DKA: Refer to DKA Protocol
Heparin infusions: Refer to Heparin Protocol (pilot)
Propofol/Diprivan: Short term use only!!!!

22. Nursing Responsibilities in Checking Drips
At the start of each shift, you must check each pump for the correct infusion rate and medication - calculate the rate, don’t trust the pump!
For each new medication infusion order or rate change, you must manually calculate the drip rate and have it independently double-checked by a second nurse

23. Let’s Shift Gears:
Drip Calculations

24. Calculating Drips Two methods can be used:
Use / memorize formulas and plug in your numbers
Use conversion ratios: extremely useful if you forget formulas! Plus, there isn’t a formula for everything we calculate

25. Calculating Drips
Try to remember that there is more than one step. With either method, start with what you know
You will need to know the patient’s weight in kilograms (# lbs divided by 2.2)
You will need the # milligrams of medication in the solution
You will need the amount of solution in milliliters (ml’s)
You will need to know the infusion rate ordered (mcg/kg/min)

26. Calculation: Example #1
Epi drip is ordered at .05 mcg/kg/min
Pt weighs 4.1 kg
Your epi syringe comes labeled .064 mg/ml
How fast do you run the pump (ml/hr)?

27. Calculation: Example #1
Use/ memorize the formula:
cc/hr = (mcg/kg/min) x (60 mins) x (wt in kg)
syringe/drip concentration in mcg
Fill in the “knowns” and do the math:
cc/hr = (.05) x (60) x (4.1) = 12.3 = .19 cc/hr

28. Calculation: Example #2
Dopamine drip ordered at 5 mcg/kg/min
Pt weighs 11 kg
Your dopamine syringe comes labeled 80 mg/ 50ml
How fast do you run the pump (ml/hr)?

29. Calculation: Example #2A
Use/memorize the formula:
cc/hr = (mcg/kg/min) x (60 mins) x (wt in kg)
syringe/drip concentration in mcg
Fill in the “knowns” and do the math:
cc/hr= (5) x (60) x (11) = 3300 = 2.1 cc/hr

30. Calculation: Example #2B
Use the formula but place the syringe med concentration in the denominator; if it’s already in mcg you are all set; if it’s in mg, do the math and then move the decimals after you get your answer
cc/hr = (mcg/kg/min) x (60 mins) x (wt in kg)
_________________________________________________________________________________________________________________________ syringe/drip concentration in mg

31. Calculation: Example #2B The easiest way??
Med concentration: 80 mg/50 mls= 1.6 mg/ml
cc/hr= (5) x (60) x (11) = 3300 = 2062
______________________________________________________________ _____________
Now move the decimal because the denominator was in mg not mcg
Answer: or 2.1 cc/hr

32. What if you know the infusion rate but don’t know the mcg/kg/min?
This calculation is used when you need to work the other way: you’ve been titrating or weaning your drip (turning the rate up/down) or a patient comes to you from the O.R. or from outside transport
Use the following formula and plug in pump rate, pt wt, and drip concentration:
mcg/kg/min= (rate) x (*drip concentration)
(pt wt) x (60)
* in mcg/ml

33. Using Conversion Ratios When All Else Fails
Set up equivalent formulas from what you know such as:
1 lb = 2.2 kg
1 mg = 1000 mcg
1 hour= 60 mins
Set up your equation so that numerators cancel out with denominators and what you want to find out is set up correctly (cc/hr not hr/cc).

34. A Conversion Ratio Example
1 gorp = 2.2 burps
1 dweeb = 1000 mini dweebs
1 jerp = 60 flibs
10 burps = 1000 mini dweebs
6 dweebs= 5 flibs
How many jerps would you have if you had 20 gorps?

35. Start with what you have and what you want
Have 20 gorps       ? Jerps
Set up your conversion ratios so that units cancel out correctly:

36. Let’s Try An Easy One Ativan ordered to be given: 1.25 mg
It comes as 2 mg /ml
Another nurse has drawn up 0.75 ml and asks you to check his/her math
Did he/she draw up the correct amount?

37. Using Conversion Ratios

38. Let’s try using Conversion Ratios with our Epi example from earlier
Epi drip ordered at .05 mcg/kg/min
Pt weighs 4.1 kg
Epi syringe comes labeled .064 mg/ml
How fast should you set you pump?

39. Start with what you have and what you want

40. Let’s try Milrinone Ordered dose is .5 mcg/kg/min
Pharmacy sends you 50 cc of Milrinone in a 60 cc syringe labeled 20 mg/100 ml
Your patient weighs 14 kg
What rate do you set your pump???

41. Using Conversion Ratios

42. Let’s see if our Milrinone rate is correct using the “formula”
cc/hr = (mcg/kg/min) x (60 mins) x (wt in kg)
*syringe/drip concentration in mcg
Convert the syringe/drip concentration to mcg/ml:
* 20 mg/100 ml = .2 mg/ml= 200 mcg/ml
Fill in the “knowns” and do the math:
cc/hr= (.5) x (60) x (14) = 420 = 2.1 cc/hr

43. Your patient is receiving Fentanyl at 1.3 ml/hr
Now You Try!!
Your patient is receiving Fentanyl at 1.3 ml/hr
The syringe is mixed 500 mcg in 50 cc
How many mcg/hr is your patient receiving?
1.3 X 500 = 13 mcg/hr
1.3 ml/ 1hr X 500 mcg/50 ml = 13 mcg/hr

44. Another One!
You’ve just come on duty to find your patient is on a dobutamine drip at 10cc/hr. You want to check the dose/rate against the original order.
Your pt weighs 20 kg
The dobutamine syringe reads “50 mg in 50 cc D5W”
How many mcg/kg/min is the dobutamine currently infusing at?
10cc/1 hr X 50 mg/50cc X 1000 mcg/1 mg x 1 hr/60 min X 1/20 kg= 10,000/1200 = 8.3 mcg/kg/min

45. Propofol Ordered mcg/kg/min as an infusion
Ordered mg/kg as incremental doses

46. Precedex (mcg/kg/hr) Use the following formula:
cc/hr = (dose ordered in mcg/kg/hr) x (wt in kg)
syringe/drip concentration: mcg/ml

47. Precedex Dose ordered: 0.2mcg/kg/hr Pt weight: 12 kg
Syringe concentration is: 4 mcg/ml
How fast would you run the pump?
If you needed to titrate the drip- What would the rate be for 0.3mcg/kg/hr?
0.4mcg/kg/hr?
0.2 x 12 divided by 4 is 0.6 cc/hr…………………… 0.2mcg/kg/hr=0.6 cc/hr
…………………………………………………………………0.3 mcg/kg/hr=0.9 cc/hr
…………………………………………………………………0.4 mcg/kg/hr= 1.2 cc/hr

48. Almost Done!!
A new “experimental drug” has just been approved for use on your patient following approval by the IRB
Drug “x” is mixed as 20 units in a 50 cc syringe
You are to infuse this new drug at a rate of 3 units/kg/hr
Your pt weighs 5 kg
How fast do you set your pump???
3 units/1kg-hr x 5kg/1 x 50cc/20units= 3x5x50/20= 750/20= 37.5 cc/hr……..have pharmacy remix more concentrated

49. Last One!!!!!!
You’ve just received an order to begin dopamine at 10 mcg/kg/min
Your pt weighs 22 lbs
Pharmacy sends you a syringe labeled “40 mg in 50cc”
What rate do you set your pump at???
First: 22lbs=10 kg
10mcg/kg-min x 1mg/1000mcg x 50cc/40 mg x 60/1 hr x 10kg/1= 7.5cc/hr
Or to use the formula, you need to convert 40mg in 50 cc to ??? mg in 1000 cc:
40 is to 50 as x is to 1000= 40000/50= 800