NOREPINEPHRINE (Levophed)

• stimulates alpha adrenergic receptors, producing vasoconstriction and decreased heart rate
• at low doses (< 2 mcg/min), stimulates beta adrenergic receptors to enhance myocardial contractility

First line pharmacological agent for the treatment of hypotension.

• beta/alpha:
  • 2.5 - 5 mcg/min by infusion, targeted to effect
• alpha: 
  • > 5 mcg/min by infusion
  • dose is titrated to effect

• Colour change from clear to brown indicates a loss of potency
• Hypovolemia, hypoxemia and acidosis should be corrected concurrently with initiation of therapy
• Should be weaned off

•  Hypersensitivity to dopamine or components (contains a sulfite preservative) - a relative contraindication and would not usually apply to emergency situations

• Inadvertent boluses may precipitate profound hypertension which may result in myocardial infarction or cerebral ischemia/bleeding
• Norepinephrine alone, without inotropic therapy may worsen stroke volume in left ventricular dysfunction in patients with poor ejection fraction 
• Bradycardia (tachycardia may occur if hypovolemic or if afterload has been increased)
• Cardiac arrhythmias, palpitations
• Chest pain
• Hypertension
• Renal ischemia resulting in decreased urine output
• Mesenteric ischemia
• Hyperglycemia
• Hypokalemia
• Headache, anxiety
• Uterine contractions
• Vomiting
• Photophobia
• Norepinephrine is a vesicant which can cause progressive and severe destruction. Extravasation of drug may cause tissue necrosis  (Rx with 5-15mg phentolamine in NS - see phentolamine monograph)

Special Risk for Torsades de Pointes (TdP):

Norepinephrine does not prolong the QT interval, BUT has a special risk of TdP because of its other actions; which includes epinephrine-like effects. It should be avoided in patients with Congenital Prolonged QT Syndrome (CLQTS). Physicians with expertise in the treatment of these arrhythmias may prescribe norepinephrine to carefully selected patients with CLQTS.

• norepinephrine + anaesthetics = increased risk of cardiac arrhythmias

• IV site
• Blood pressure
• Continuous heart rate and rhythm
• Hourly urine output
• Urea, creatinine
• Central or mixed venous oxygen saturation
• Lactate
• Blood gases
• Electrolytes
• Glucose
• Cardiac index if available
• SVRI if monitored
• Changes in skin colour or temperature

• May be administered by IV infusion by a nurse in Adult Critical Care.
• May be titrated by a nurse in Adult Critical Care.
• Must be administered via central venous access device if protocol for peripheral vasopressor administration cannot be met; in emergency situations may be temporarily infused through a peripheral vascular access device until a central venous line can be established.
• Monitor peripheral site closely and document Infiltration and Phlebitis scale Q1H. Knowledge of the treatment for infiltration of vasoconstricting drugs is required. 
• Single agent dopamine or norepinephrine may be administered for up to 24 hours when short term use is anticipated; follow the Administration of Peripheral Vasopressors Policy for required orders, timelines, assessment and documentation.
• Patient requires placement of an arterial line to monitor BP and titrate drug.  Single agent dopamine or norepinephrine infusions anticipated to be required for less than 24 hours may be managed with non-invasive blood pressure monitoring.  Follow the Deferral of Arterial Line Placement Policy for required orders, timelines, assessment and documentation. 
• Continuous infusions must be administered by infusion device and the pump library must be enabled.
• Should not be infused via the proximal injectate port (blue) of a pulmonary artery catheter. If this is the only available central venous line, it may be administered through the proximal injectate port but thermodilution cardiac output measurements must not be measured during infusion).