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VasopressorsJennifer & Joshua Chalk Talk
1/17/2014
Go Hawks!
Vasopressors
What?
When?
Why?
Wprecautions?
Vasopressors
Definitions
Pressor: Increases blood pressure by stimulating constriction of blood vessels Increases vascular tone
Definitions
Inotrope: Alters force or energy of muscular contractions Positive: Increases myocardial contractility
Definitions
Shock: Inability of oxygen delivery to meet tissue oxygen requirements Hypovolemia (decreased circulating volume) Cardiac function impairment (decreased
myocardial contractility) Inappropriate distribution of cardiac output
secondary to abnormal vasodilatation
Pathophysiology
Cardiac output Heart Rate
Sympathetic and Parasympathetic toneCirculating chatecolamines
Preload Changes in venous returnChanges in plasma volume
ContractilitySympathetic toneCirculating catecholamines
Progression to Late Shock
Septic Shock
Hypotension despite adequate fluid resuscitation
Presence of hypoperfusion or organ dysfunction
Acidosis / alteration in mental status Sepsis: temp >38°C or <36°C; HR> 90 bpm*
respiratory rate>20 breaths/min, need for mechanical ventilation; WBC 12,000*
Hemorrhagic Shock
Rapid reduction in blood volume
Heart rate and blood pressure responses can be variable
Vasopressors may be harmful if pt is hypovolemic; Despite improvement in blood pressure, renal blood flow decreases and renal vascular resistance rises
Cardiogenic Shock
Pump failure
Results when more than 40% of myocardium damaged
Similar circulatory and metabolic changes to hemorrhagic shock
Treatment
1. Fluids / Procedures
2. DRUGS! Vasopressors Inotropes
Fluid Requirements
“There is no evidence-based support for one fluid-type over another”(surviving sepsis)
Early fluid administration more important than fluid type HES/Albumin/Gelatin/LR; Rivers et al
Pharmacology
Pharmacology
Adrenergic System Alpha adrenergic
Increases vascular toneMay decrease cardiac outputMay decrease regional blood flow (renal, spleen, cutaneous)
Beta adrenergicMaintains blood flowMay increase cellular metabolismMay decrease immune system
Pharmacology
Dopaminergic Increases splanchnic and renal perfusion Facilitates resolution of lung edema Associated with harmful immunological effects May decrease prolactin, human growth
hormone
Vasopressors
Norepinephrine
Dopamine
Epinephrine
Vasopressin
Phenylephrine
Vasopressors
Phenylephrine
Vasopressors
Vasopressors
Vasopressin
Receptors
Receptors
Norepinephrine
Historically considered a poor choice in shock due to excessive vasoconstriction and end-organ hypoperfusion
This opinion began to change recently
Benefits: raise arterial pressure and systemic vascular resistance
Maintain cardiac function / improve renal function
Dopamine
More potential for arrhythmias/increased heart rate
May increase both blood pressures and flow; may be best used in patient with low heart rate and inadequate fluid resuscitation
Epinephrine
Epi often used as 3rd line after NE and DA failed
Epi always first line in Anaphylactic Shock
Vasopressin
Vasopressin works on V1,V2,V3 receptors
Increases bp / may improve mortality
May decrease NE requirements
May improve renal function
Avoid in MI; in cardiac ischemia may decrease contractility/lower CO/increase mortality
At doses > 0.04 units/hr may decrease GI blood flow
Studies
VASST Vasopressin (0.03 un/hr) v. NE in septic shock No significant difference in mortality at 28
days Decreased mortality in patients with less
severe septic shock (lowest quartile of arterial lactate)
Vaso + corticosteroids decreased mortality v. NE + corticosteroids
Conclusion: May be effective in patients with less severe septic shock already receiving NE
Studies
Martin: Norepi in Septic Shock 97 patients in septic shock Dopamine started at 5mcg/kg/min, titrated to
15mcg/kg/min If hypotension persisted:
DA increased to 25mcg/kg/min OR
NE added at 0.5mcg/kg/min
Martin et al
Patients receiving NE had best survival rate on all days of hospital stay (p<0.001)
Mortality strongly associated with high lactate and low urine output“NE was associated with a highly significant decrease in hospital mortality. The data contradict the notion that norepinephrine potentiates end organ hypoperfusion through excessive vasoconstriction
Studies
De Backer: Norepi v Dopamine in Shock.
Multicenter study, 1679 patients DA with 52.5% mortality NE with 48.5% mortality (p=0.10) More arrhythmic events with DA (207v102)
DeBacker et al
Included Septic (62.2%), Cardiogenic (16.7%), and Hypovolemic (15.7%) shock.
More patients in DA group required 2nd pressor
Subgroup: DA in cardiogenic shock increased mortality significantly (p=0.03)
Conclusion: “This study raised serious concern about the safety of Dopamine”
Practical Considerations
• Vascular Access• Access to drug• Compatibilities• Titration• Adverse effects
Central vs. Peripheral line
Central always preferred Peripheral
LineMust flush wellAs big as possiblePreferred infusion site = forearm (basilic, cephalic, and median antebrachial)
Caution with dorsum of hand, wrist, feet Decision: life vs. limb
MD must be aware Guardrails alert: pressor must go through central line
Override with MD approval documented Slower titration with obese patients
Central vs. Peripheral line
Jean-Damien, R et al. Central or peripheral catheters for initial venous access of ICU patients
Patients randomized: peripheral (N=128) or central access (N=135)
Included epinephrine/norepinephrine doses up ~0.4 mcg/kg/min (for 75 kg patient); Dopamine/dobutamine doses up to 10 mcg/kg/min
Less major complications with central rather than peripheral access (0.64 vs. 1.04, p<0.02)
Majority of complications in PIV group were inability to insert PIV Subcutaneous diffusion (aka extravasation)
More with peripheral rather than central access 19/128 (~15%) vs. 2/135 (~1.5%) Average length of stay ~12 days
All patients managed with “observation and conservative management”
http://emcrit.org/podcasts/peripheral-vasopressors-extravasation/Ricard JD, et al. Central or peripheral catheters for initial venous access of ICU patients: a randomized controlled trial. Crit Care Med. 2013 Sep;41(9):2108-15
Extravasation
Drug Effect Mechanism(s) of tissue injury
Dobutamine Irritant; Rare reports of vesicant effects
Cytotoxicity, acidic pH
Dopamine, Epinephrine, Phenylephrine Norepinephrine, Vasopressin
Vesicants Vasoconstriction
Extravasation
Phentolamine Short-term alpha-
adrenergic blocking activity
Administration →vasodilatation of vascular smooth muscle
Administer ASAP Infiltrate area of
extravasation with phentolamine: 5 mg diluted in 9 mL NS
Should see near immediate effects; otherwise consider additional dose (Max = 10 mg)
Getting a Drip Up and On
Sequence of events Hypotensive patient Recognize pressor needed Physician orders Order recognized in ORCA Pharmacy technician makes drip Pharmacist checks drip Pharmacy technician tubes drip Nurse collects from tube station Nurse starts drip
Getting a Drip Up and On
Dopamine, Dobutamine
Premixed and in PYXIS!
Epinephrine, Phenylephrine, Norepinephrine, Vasopressin
Mixed by technician after order received in inpatient pharmacy
Getting a Drip Up and On
Persistent hypotension → Ask MD if drip should be sent to bedside
Cost to hospital per bag: $1.56 – 7.23 Call pharmacy
Ask for pharmacist STAT (state you are calling from ED)
State patient scenario briefly Request pharmacy to start making drip
ONLY Physician may give verbal order with U#, drug and doseOtherwise MD must place order in ORCA before drip is sent
Request pharmacy to notify PSS when drip sent
Compatibilities
Variable – Call pharmacyMost likely to be compatible: Epinephrine, dobutamine, dopamine, vasopressin
Maybe: Phenylephrine
Generally not tested: Norepinephrine
Titration
Starting a drip MD must order Generally best to start low and increase
Adverse effects frequently dose related
Switching a patient from OSH Check patient weight and dosing UNITS
If the same, transition to UW pump and drugIf different:
Call pharmacy to convert Start in the low to mid range of dosing and titrate
Adverse Reactions
Epinephrine Norepinephrine Dopamine Dobutamine VasopressinPhenylephrine
Tachycardia x High doses xArrhythmias x High doses x x (ventricular)Increased myocardial O2 demand x x xDecreased perfusion to vital organs x x x (less) xNausea/vomiting x xMetabolic acidosis x x
Hypersensitivity
x (contains sulfites)
Extravasation x x x x x x
References
De Backer D et al. Comparison of dopamine and norepinephrine in the treatment of shock. N Engl J Med 2010;362:779-89.
Martin C et al. Effect of norepinephrine on the outcome of shock. Crit Care Med 2000; 28:2758 –2765
Perel A. The initial hemodynamic resuscitation of the septic patient according to Surviving Sepsis Campaign guidelines – does one size fit all? Critical Care 2008, 12:223
Russel J. Vasopressin in the management of septic shock. Critical Care 2011, 15:226
Russell JA, et al. Vasopressin versus norepinephrine infusion in patients with septic shock. N Engl J Med 2008, 358:877-887.
Ricard JD, et al. Central or peripheral catheters for initial venous access of ICU patients: a randomized controlled trial. Crit Care Med. 2013 Sep;41(9):2108-15