How to Prepare Norepinephrine Infusion for Shock
For adult patients in shock, prepare norepinephrine by adding 4 mg to 250 mL of D5W to create a standard concentration of 16 μg/mL, then start the infusion at 0.5 mg/h (approximately 0.1 μg/kg/min) and titrate upward based on blood pressure response. 1
Standard Adult Preparation
- Mix 4 mg of norepinephrine in 250 mL of D5W to achieve a concentration of 16 μg/mL 1
- Start infusion at 0.5 mg/h and titrate up to a maximum of 3 mg/h based on patient response 1
- The goal is to increase mean arterial pressure (MAP) by 10 mmHg or achieve urine output >50 mL/h 1
- Target MAP of 65 mmHg for septic shock patients 1
Pediatric Preparation Using "Rule of 6"
- Calculate: 0.6 × body weight (kg) = number of milligrams to add to 100 mL of saline 1
- With this dilution, 1 mL/h delivers 0.1 mcg/kg/min 1
- Typical pediatric dosing ranges from 0.1-1.0 mcg/kg/min, starting at the lowest dose and titrating to effect 1
- Doses as high as 5 mcg/kg/min may be necessary in some children 1
Alternative Concentration for Resource-Limited Settings
- When infusion pumps are unavailable, dilute 250 mg dopamine or 5-10 mg epinephrine in 500 mL crystalloid and use a drop regulator 2
- For norepinephrine specifically in anaphylaxis: add 1 mg to 100 mL saline (1:100,000 solution) and administer at 30-100 mL/h 1
Administration Route
- Central venous access is strongly preferred to minimize extravasation risk 1
- If central access is unavailable or delayed, peripheral IV or intraosseous access can be used temporarily with strict monitoring 2, 1
- Use a large bore vein for peripheral administration 2
- Check infusion site frequently for signs of extravasation, as substantial skin necrosis can occur 2
Critical Pre-Administration Requirements
Address hypovolemia FIRST before starting norepinephrine by administering fluid boluses (minimum 30 mL/kg crystalloid) to optimize cardiac output 1. Vasoconstriction in hypovolemic patients causes severe organ hypoperfusion despite "normal" blood pressure 1. This is a strong recommendation with moderate quality evidence from the Surviving Sepsis Campaign 1.
Monitoring Protocol
- Measure blood pressure and heart rate every 5-15 minutes during initial titration 2, 1
- Use appropriately sized cuffs in children to ensure accurate readings 2
- Monitor for signs of excessive vasoconstriction: cold extremities, decreased urine output 1
- Watch for potential side effects including hypertension, arrhythmias, and tissue ischemia 1
Titration Strategy
- Increase dose by 0.5 mg/h every 4 hours as needed, up to maximum of 3 mg/h 1
- Titrate to achieve target MAP or adequate tissue perfusion 1
- For septic shock, target normalization of capillary refill and age-appropriate heart rate 1
- If shock remains refractory to high-dose norepinephrine, consider adding vasopressin rather than continuing to escalate norepinephrine alone 3
Timing Considerations
Early administration of norepinephrine is beneficial - start simultaneously with fluid resuscitation in patients with profound hypotension rather than waiting until fluid resuscitation is complete 4, 5. This is particularly important when:
- Diastolic blood pressure ≤40 mmHg 5
- Diastolic shock index (heart rate/diastolic BP) ≥3 5
- Fluid accumulation would be particularly deleterious (ARDS, intra-abdominal hypertension) 5
Early norepinephrine administration increases shock control rates, improves cardiac output and microcirculation, and avoids fluid overload 4, 5.
Critical Safety Precautions
- Never mix norepinephrine with sodium bicarbonate or alkaline solutions in the IV line, as they inactivate catecholamines 1
- If extravasation occurs, immediately infiltrate phentolamine 5-10 mg diluted in 10-15 mL saline into the site to prevent tissue necrosis 1
- Pediatric phentolamine dose: 0.1-0.2 mg/kg up to 10 mg 1