Management of Hypotension Post Plasma Exchange
Initiate crystalloid fluid resuscitation with 0.9% sodium chloride or balanced crystalloid solution, perform passive leg raise testing to assess fluid responsiveness, and add norepinephrine as first-line vasopressor if hypotension persists despite adequate fluid therapy or if the patient is not fluid responsive. 1
Initial Hemodynamic Assessment
Before initiating treatment, perform bedside hemodynamic assessment to determine the underlying cause of hypotension 1. Use passive leg raise (PLR) testing to predict fluid responsiveness, which has a positive likelihood ratio of 11 and specificity of 92% 1. This is critical because approximately 50% of hypotensive patients post-procedure will respond to fluid administration, while the remaining 50% require vasopressor or inotropic support rather than volume expansion 1.
Non-invasive cardiac output monitors or portable ultrasound can identify whether hypotension results from inadequate preload, reduced vascular tone, or myocardial dysfunction 1. This distinction guides whether to continue fluids, initiate vasopressors, or add inotropic support.
Fluid Resuscitation Strategy
If PLR testing is positive, initiate crystalloid fluid resuscitation with 0.9% sodium chloride or balanced crystalloid solution 1. Administer fluid boluses judiciously to achieve target blood pressure while avoiding excessive volume administration 1.
Avoid colloids, including albumin, as they have adverse effects on hemostasis and lack demonstrated superiority over crystalloids 1. This recommendation is supported by research showing that 5% albumin is no more effective than normal saline for treating hypotension in similar clinical contexts 2. Additionally, partial saline replacement during plasma exchange is associated with increased hypotensive reactions compared to albumin alone, but this does not justify using albumin to treat post-procedure hypotension 3.
Target a mean arterial pressure of 65 mmHg or systolic blood pressure of 80-100 mmHg during initial resuscitation 4, 1. However, if there is any concern for brain injury or chronic hypertension, maintain a higher mean arterial pressure of at least 80 mmHg 1.
Vasopressor Therapy
If fluid resuscitation fails to achieve target blood pressure or PLR testing is negative, initiate norepinephrine as the first-line vasopressor 1, 5. Norepinephrine should be administered in addition to fluids, not as a replacement for appropriate volume resuscitation 1.
For norepinephrine administration, dilute 4 mg in 1,000 mL of 5% dextrose solution (yielding 4 mcg/mL) 5. Start with an initial infusion rate of 2-3 mL per minute (8-12 mcg per minute), then adjust to maintain adequate blood pressure 5. The average maintenance dose ranges from 0.5-1 mL per minute (2-4 mcg per minute) 5. Administer through a large central vein using a plastic intravenous catheter to avoid extravasation 5.
Avoid phenylephrine in bradycardic patients as it can cause reflex bradycardia, especially in preload-independent states 1.
Inotropic Support
If myocardial dysfunction is identified as the cause of hypotension through bedside assessment or ultrasound, administer dobutamine 1. Inotropic agents are indicated when hypotension results from reduced cardiac contractility rather than inadequate preload or vascular tone 1.
Monitoring and Escalation
Monitor for symptomatic hypotension requiring immediate treatment 1. Document hemodynamic parameters before and after interventions 1. For persistent hypotension despite initial therapy, reassess fluid status and cardiac function using available monitoring tools 1.
Transfer to a higher level of care if hypotension persists despite initial interventions or if the patient requires multiple vasoactive agents 1. Consider adding additional vasopressor support if single-agent therapy is insufficient 1.
Common Pitfalls to Avoid
- Do not delay vasopressor initiation if the patient remains hypotensive despite adequate fluid resuscitation 1
- Avoid excessive fluid administration, which can lead to hemodilution and worsening of coagulation without added hemodynamic benefit 1
- Do not use albumin routinely for hypotension management post-plasma exchange, as it is expensive and not more effective than crystalloids 1, 2, 6
- Recognize that plasma exchange itself causes plasma volume depletion (13.5-18.5% reduction) and hemodynamic changes including decreased cardiac index (25-38%) and pulmonary wedge pressure (36-41%), which explains the high incidence of post-procedure hypotension 7