What is a sample doctor's order for norepinephrine in a patient with hypotension?

Sample Norepinephrine Order for Hypotension

Start norepinephrine at 0.5 mg/hour (approximately 8-12 mcg/min or 0.1-0.5 mcg/kg/min) via continuous IV infusion through central venous access, while simultaneously administering at least 30 mL/kg crystalloid bolus, targeting a mean arterial pressure (MAP) of 65 mmHg. 1, 2

Preparation and Dilution

• Standard concentration: Add 4 mg of norepinephrine to 1,000 mL of 5% dextrose injection (or 5% dextrose and sodium chloride) to yield 4 mcg/mL 2
• Alternative concentration: Add 4 mg of norepinephrine to 250 mL of D5W to yield 16 mcg/mL 1
• Critical: Use only dextrose-containing solutions, as these protect against potency loss from oxidation; administration in saline alone is not recommended 2
• Do not mix with sodium bicarbonate or other alkaline solutions in the IV line, as norepinephrine is inactivated in alkaline solutions 1

Administration Route and Access

• Strongly preferred: Central venous catheter to minimize extravasation risk and tissue necrosis 1, 3, 2
• If central access unavailable or delayed: Peripheral IV can be used temporarily with strict monitoring, but transition to central access as soon as practical 1
• Insert plastic IV catheter through suitable bore needle well advanced centrally into vein and securely fixed with adhesive tape 2
• Use IV drip chamber or suitable metering device to permit accurate flow rate estimation 2

Initial Dosing

• Starting dose: 0.5 mg/hour (8-12 mcg/min or 0.1-0.5 mcg/kg/min for 70 kg adult) 1, 3, 2
• After observing response to initial 2-3 mL/min (8-12 mcg base/min), adjust flow rate to establish and maintain target blood pressure 2

Target Blood Pressure

• Primary target: MAP ≥65 mmHg 1, 3, 4
• Alternative systolic target: 80-100 mmHg systolic sufficient to maintain circulation to vital organs 2
• In previously hypertensive patients: Raise blood pressure no higher than 40 mmHg below pre-existing systolic pressure 2

Titration Protocol

• Maintenance dose range: 0.5-1 mL/min (2-4 mcg base/min) 2
• Increase dose by 0.5 mg/hour every 4 hours as needed, up to maximum of 3 mg/hour 1, 4
• Titrate according to individual patient response; great variation occurs in required dose 2
• Occasionally much larger doses (as high as 68 mg base daily) may be necessary if patient remains hypotensive 2

Critical Pre-Administration Requirements

• Mandatory fluid resuscitation: Administer minimum 30 mL/kg crystalloid bolus before or concurrent with norepinephrine initiation 1, 4
• Exception for severe hypotension: In life-threatening hypotension (systolic <70 mmHg), start norepinephrine as emergency measure while fluid resuscitation continues rather than waiting for complete volume repletion 4, 5
• Always suspect and correct occult blood volume depletion if patient remains hypotensive despite high doses 2
• Central venous pressure monitoring is usually helpful in detecting and treating volume depletion 2

Monitoring Requirements

• Arterial catheter: Place as soon as practical for continuous blood pressure monitoring 1, 4
• Monitor blood pressure and heart rate every 5-15 minutes during initial titration 1, 4
• Tissue perfusion markers: Assess urine output (target >0.5 mL/kg/h), lactate levels, mental status, skin perfusion (temperature, capillary refill) 4, 6
• Monitor for signs of extravasation continuously 3

Escalation Strategy for Refractory Hypotension

• When norepinephrine reaches 0.25 mcg/kg/min: Add vasopressin 0.03-0.04 units/min as second-line therapy rather than continuing to escalate norepinephrine alone 4
• For persistent hypoperfusion despite adequate vasopressors: Add dobutamine up to 20 mcg/kg/min 1
• Consider hydrocortisone 50 mg IV every 6 hours (or 200 mg continuous infusion) for refractory shock requiring high-dose vasopressors 4
• Avoid: Dopamine as first-line agent (associated with higher mortality and arrhythmias); use only in highly selected patients with absolute bradycardia and low arrhythmia risk 3, 4

Extravasation Management

• If extravasation occurs: Immediately infiltrate 5-10 mg of phentolamine diluted in 10-15 mL of saline into the site to prevent tissue necrosis and sloughing 1, 3, 2
• Pediatric phentolamine dose: 0.1-0.2 mg/kg up to 10 mg diluted in 10 mL of 0.9% sodium chloride 1

Duration and Weaning

• Continue infusion until adequate blood pressure and tissue perfusion are maintained without therapy 2
• Reduce gradually, avoiding abrupt withdrawal 2
• Decrease by 25% of current dose every 30 minutes as tolerated 3
• Treatment may be required for up to 6 days in cases of vascular collapse from acute myocardial infarction 2

Special Considerations and Precautions

• Use cautiously in patients with ischemic heart disease, as norepinephrine may increase myocardial oxygen demand 3
• Higher doses (>10 mcg/min) are associated with increased mortality and should be avoided if possible 3
• In septic shock, norepinephrine may actually improve renal blood flow and urine output despite causing renal vasoconstriction in other contexts 3
• Early administration (within first hour) in severely hypotensive patients (diastolic BP ≤40 mmHg or diastolic shock index ≥3) may reduce mortality and fluid accumulation 5, 6

Common Pitfalls to Avoid

• Never use hydroxyethyl starch (HES) for fluid resuscitation with norepinephrine due to increased mortality (51% vs 43%) 1
• Do not rely solely on fluids to restore blood pressure in profound hypotension, as response is inconstant, delayed, and transitory 5
• Do not use phenylephrine as first-line agent; reserve only for specific circumstances such as norepinephrine causing serious arrhythmias 1
• Do not use low-dose dopamine for renal protection—it has no benefit 1
• Inspect solution visually before use; do not use if color is pinkish or darker than slightly yellow, or if it contains precipitate 2