NAPLEX: Special Populations - Acute & Critical Care

crystalloids

- where they remain

- $

- AE

contain Na and/or dextrose that passes between semipermeable membranes

move into extravascular or interstitial space

less costly

fewer AE

colloids

- where they remain

- $

- AE

large molecules (typically protein, starch) dispersed in solution

stay in intravascular space (blood vessels) and increase oncotic pressure

more expensive

not clear clinical benefit over crystalloids

common examples of crystalloids

- 5% dextrose (D5W)

- 0.9% NaCl (normal saline, NS)

- lactated ringer (LR)

- multiple electrolyte injection (plasma lyte A)

common examples of colloids

- albumin 5%, 25% (albutein, alburx)

- dextran

- hydroxyethyl starch (hespan, hextend)

hyponatremia

Na <135 mEq/L

symptomatic hyponatremia

Na <120 mEq/L

unless serum levels fall rapidly (acute hyponatremia)

hypervolemic hyponatremia

- cause

- treatment

cause: fluid overload (cirrhosis, HF, renal failure)

treatment:

- diuresis with fluid restriction

- AVP receptor antagonists (conivaptan, tolvaptan)

isovolemic (euvolemic) hyponatremia

- cause

- treatment

cause: inappropriate antidiuretic hormone (SIADH)

treatment:

- diuresis with fluid restriction

- stopping drugs that induce SIADH

- AVP receptor antagonists (conivaptan, tolvaptan)

- demeclocycline for SIADH

hypovolemic hyponatremia

- cause

- treatment

cause: diuretics, salt wasting syndromes, adrenal insufficiency, blood loss, vomiting / diarrhea

treatment

- correct underlying cause

- stop intake of hypotonic solutions

- if acute hyponatremia, severe sx, or Na <120: hypertonic (3%) sodium chloride IV

hyponatremia correction goal

4-8 mEq/L/24 hrs

if corrected more rapidly than 12 mEq/L/24 hrs can cause ODS

give desmopressin to reduce water diuresis + avoid overcorrection

how long can tolvaptan (PO) be used

30 days

hypernatremia

Na > 145 mEq/L

hypovolemic hypernatremia

- cause

- treatment

cause: dehydration, vomiting, diarrhea

treatment: fluids

hypervolumic hypernatremia

- cause

- treatment

cause: intake of hypertonic fluids

treatment: diuresis

isovolemic (euvolemic) hypernatremia

- cause

- treatment

cause: diabetes insipidus (DI) --> decreases ADH

treatment: desmopressin

hypokalemia

K <3.5 mEq/L

hypokalemia treatment

serum K <2.6

100 mEq KCl IV

contact MD

hypokalemia treatment

serum K 2.6-2.9

80 mEq KCl IV

contact MD

hypokalemia treatment

serum K 3.0-3.2

60 mEq KCl PO/IV

hypokalemia treatment

serum K 3.3-3.5

40 mEq KCl PO/IV

hypokalemia treatment

- line to administer through

- maximum infusion rate

- maximum concentration

line: peripheral

max infusion rate: <10 mEq/hr

max concentration: 10 mEq/100 mL

if hypokalemia is resistant to treatment what should be checked

serum magnesium

if hypokalemia and hypomagnesemia are both present which should be corrected first

magnesium

hypomagnesemia

Mg <1.3 mEq/L

hypomagnesemia treatment

Mg <1 mEq/L with life threatening sx

IV magnesium sulfate replacement

hypomagnesemia treatment

Mg <1 mEq/L wit no life threatening sx

IV or IM magnesium sulfate replacement

hypomagnesemia treatment

Mg >1 mEq and <1.5 mEq

replace with PO magnesium oxide

hypomagnesemia treatment

replacement duration

5 days

hypophosphatemia

<1 mg/dL

hypophosphatemia treatment

if serum PO4 <1 mg/dL - IV phosphorus

- 0.08-0.16 mmol/kg in 500 mL of NS or D5W over 6 hrs is common

if less severe can use PO

hypophosphatemia treatment

replacement duration

1 week

dopamine dosing

low dose

- dose

- which receptors are hit

dose: 1-4 mcg/kg/min

receptors: dopamine 1 agonist

dopamine dosing

medium dose

- dose

- which receptors are hit

dose: 5-10 mcg/kg/min

receptors: beta 1 agonist

dopamine dosing

high dose

- dose

- which receptors are hit

dose: 10-20 mcg/kg/min

receptors: alpha 1 agonist

which line should vasopressors be administered through to reduce risk of extravasation

central line

extravasation treatment

vasopressors

phentolamine (alpha 1 blocker)

alt: nitroglycerin ointment

extravasation treatment

norepinephrine, epinephrine, phenylephrine

stop infusion but do not disconnect needle/canula

do not flush line

gently aspirate drug

NTG effectiveness duration

24-48 hrs d/t tachyphylaxis

true or false

nitroprusside has a greater effect on BP than NTG

true

what can be administered w nitroprusside to reduce risk of thiocyanate toxicity or treat cyanide toxicity

hydroxocobalamin

types of shock

- Hypovolemic (hemorrhagic)

- Distributive (septic, anaphylactic)

- Cardiogenic (post MI)

- Obstructive (massive pulmonary embolism)

hypovolemic shock

treatment

1st line = fluid resuscitation w crystalloids

blood products should be administered if intravascular depletion d/t bleeding

if pt doesn't respond to initial crystalloid or blood product therapy can start vasopressors

sepsis treatment target

MAP >65

septic shock treatment

- early admin of broad spectrum abx

- fluid resuscitation with IV crystalloids

- vasopressors if adequate perfusion cannot be maintained with IV crystalloids

norepinephrine = vasopressor of choice

vasopressin often used in addition

ADHF - drugs that worsen

negative inotropes (non DHP CCB)

drugs that cause fluid retention (NSAIDs)

cardiotoxic drugs

when should beta blocker be stopped in ADHF

if hypotension or hypoperfusion is present

ADHF (cardiogenic shock) treatment

volume overload

- loop diuretics

- vasodilators (NTG, nitroprusside)

hypoperfusion

- inotropes (dobutamine, milrinone)

- if hypotensive add vasopressor (dopamine, norepinephrine, phenylephrine)

pain treatment

1st line = IV opioids

adjuvants (APAP, NSAIDs) can be added

fentanyl has a ____ (higher/lower) risk of HoTN than morphine

lower

fentanyl is ____ (more/less) potent than morphine

more

100x more potent

fentanyl has a ____ (rapid/slow) onset and ____ (short/long) duration of action

rapid onset

short duration of action

fentanyl can accumulate in _____ (renal/hepatic) impairment

hepatic

agitation treatment

BZD

- lorazepam (ativan)

- midazolam (versed); caution in renal dysfunction

non BZD

- propofol (diprivan)

- dexmedetomidine (precedex); can be used in both intubated and non intubated patients

- etomidate

- ketamine

delirium treatment

- quetiapine (preferred)

- haloperidol

sedation w non BZD vs BZD may help reduce delirium

stress ulcer treatment

- H2RA

- PPI

risk factors for development of stress ulcers

Mechanical ventilation >48 hrs

Coagulopathy

Sepsis

Traumatic brain injury

Major burns

Acute renal failure

High dose systemic steroids

commonly used local anesthetics

lidocaine (xylocaine)

benzocaine

liposomal bupivacaine (exparel)

commonly used inhaled anesthetics

desflurane (suprane)

sevolurane (ultane)

isoflurane (forane)

nitrous oxide

commonly used injectable anesthetics

bupivacaine (marcaine, sensorcaine)

lidocaine (xylocaine)

ropivacaine (naropin)

depolarizing NMBA

succinylcholine

succinylcholine is ____ (short/long) acting and has a ____ (rapid/slow) onset

short acting

fast onset (30-60 seconds)

non depolarizing NMBA

Atracurium

Cisatracurium (nimbex)

Pancuronium

Rocuronium

Vercuronicum

drugs that can enhance neuromuscular blocking activity / lead to toxicity

Aminoglycosides

Polymyxins

CCB

Cyclosporine

Inhaled anesthetics

Lithium

Quinidine

Vancoymycin

arginine vasopressin (AVP) receptor antagonist examples

- conivaptan (vaprisol) injection

- tolvaptan (samsca) tablet

AVP receptor antagonist renal cutoffs

conivaptan: CrCl <30

tolvaptan: CrCl <10

conivaptan SE

Orthostatic HoTN

Fever

Hypokalemia

Infusion site reactions (>60%)

must be started in the hospital to monitor Na

tolvaptan SE

warnings:

- osmotic demylination syndrome (ODS)

- hepatotoxicity

Thirst

Nausea

Dry mouth

Polyuria

Weakness

Hyperglycemia

Hypernatremia

must be started in the hospital to monitor Na

IVIG administration instructions

do not freeze, shake, or heat

may need slower titration and premedication

lot #'s need to be tracked

IVIG populations to use caution in

CV disease

IVIG SE

Headache

Nausea

Diarrhea

Injection site reactions

Infusion reaction (flushing, chest tightness, fever, chills, HoTN) - slow/stop infusion

Renal failure

Blood dyscrasias

vasopressor examples

- dopamine

- epinephrine

- norepinephrine

- phenyleprine

- vasopressin

vasopressor SE

Arrhythmias

Tachycardia (especially dopamine, epinephrine)

Necrosis (gangrene)

Bradycardia (phenylephrine)

Hyperglycemia (epinephrine)

Tachyphylaxis

Peripheral and gut ischemia

vasopressor CI

pt taking MAOi

vasopressors should be administered through ____ line

central line

epinephrine used for IV push is ____ mg/mL + ____ ratio strength

0.1 mg/mL

1:10000 ratio strength

epinephrine used for IM injection or compounding is ____ mg/mL + ____ ratio strength

1 mg/mL

1:1000 ratio strength

nitroglycerin administration instructions

Requires non PVC container (glass, polyolefin)

Use administration sets (tubing) intended

nitroprusside administration instructions

Not for direct injection - must be further diluted, D5W preferred

Requires light protection during administration

Use only clear solutions

propofol CI

hypersensitivity to egg, egg products, soy, or soy products

propofol administration instructions

shake well before use - do not use if separation of phases in emulsion

use strict aseptic technique d/t potential for bacterial growth

- discard vial and tubing within 12 hrs of use

- if transferred to a syringe prior to admin discard syringe within 6 hrs

do not use filter <5 microns for administration

no need to refrigerate

oil in water emultion provides 1.1 kcal/mL

short t1/2 non depolarizing NMBAs

- atracurium

- cisatracurium (nimbex)

intermediate acting non depolarizing NMBAs

- atracurium

- cisatracurium (nimbex)

- rocuronium

- vecuronium

long acting non polarizing NMBAs

pancuronium

which NMBA can accumulate in renal or hepatic dysfunction

pancuronium

vecuronium

maximum sodium correction

<12 mEq/L/day or slower

if exceeded risk of osmotic demyelination syndrome

drop of ___ mEq/L in K (below 3.5 mEq/L) represents a total body deficit of 100-400 mEq

drop of 1 mEq/L in K (below 3.5 mEq/L) represents a total body deficit of 100-400 mEq

apache score

scoring system to determine how likely a pt is to die in the ICU

ICU medications that target the SNS

- vasopressors

- vasodilators

- inotropes

nitroglycerin at low doses is a ___ (venous/arterial) vasodilator

primarily effects ___ (preload/afterload)

venous vasodilator

preload

nitroglycerin at high doses is a ___ (venous/arterial) vasodilator

primarily effects ___ (preload/afterload)

arterial vasodilator

afterload

dobutamine MOA

beta 1 agonist

milrinone MOA

PDE-3 inhibitor

H2RA SE

thrombocytopenia

CNS SE

PPI SE

c diff

osteoporotic fractures

nosocomial pneumonia

NMBAs must be given with what

ventilator

pain agents

NMBAs paralyze patients and cause respiratory depression (must be on ventilator), does not necessarily provide pain relief (need pain agents)

hemostatic agent example

- aminocaproic acid (amicar)

- tranexamic acid (cyklokapron IV, lysteda oral)

- recombinant factor VIIa (NovoSeven RT)