How to manage hypotension (low blood pressure) post plasma exchange?

Management of Hypotension Post Plasma Exchange

Immediately assess fluid responsiveness using passive leg raise (PLR) testing, then administer crystalloid fluids (0.9% saline or balanced crystalloid) if PLR-positive; if hypotension persists despite fluid resuscitation or PLR is negative, initiate noradrenaline as the vasopressor of choice. 1

Initial Assessment and Fluid Responsiveness Testing

Perform bedside hemodynamic assessment to determine the underlying cause of hypotension before initiating treatment. 1

• Use passive leg raise (PLR) testing to predict fluid responsiveness: An increase in cardiac output after PLR strongly predicts fluid responsiveness (positive likelihood ratio = 11, specificity 92%), while no increase effectively rules out fluid responsiveness (negative likelihood ratio = 0.13, sensitivity 88%). 1

• Recognize that only approximately 50% of hypotensive patients post-procedure will respond to fluid administration, meaning the remaining patients require vasopressor or inotropic support rather than volume expansion. 1

• Consider non-invasive cardiac output monitors or portable ultrasound devices to identify whether the hypotension is due to inadequate preload, reduced vascular tone, or myocardial dysfunction. 1

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 using colloids due to adverse effects on hemostasis and lack of demonstrated superiority over crystalloids. 1

• Important caveat: Albumin administration during plasma exchange is NOT more effective than normal saline for treating hypotension and should not be routinely used for this indication. 2, 3

Vasopressor Therapy

If fluid resuscitation fails to achieve target blood pressure or PLR testing is negative, initiate noradrenaline (norepinephrine) as the first-line vasopressor. 1

• Noradrenaline is recommended to maintain target arterial pressure when restricted volume replacement does not achieve blood pressure goals (Grade 1C recommendation). 1

• Administer noradrenaline in addition to fluids, not as a replacement for appropriate volume resuscitation. 1

• Avoid phenylephrine in bradycardic patients as it can cause reflex bradycardia, especially in preload-independent states; phenylephrine is best reserved for hypotension accompanied by tachycardia. 1

• Consider the patient's hemodynamic profile when selecting vasopressors: Different agents have varying effects on heart rate, contractility, and vascular tone. 1

Inotropic Support

Administer dobutamine if myocardial dysfunction is identified as the cause of hypotension (Grade 1C recommendation). 1

• Inotropic agents are indicated when hypotension results from reduced cardiac contractility rather than inadequate preload or vascular tone. 1

Critical Pitfalls and Special Considerations

Avoid routine albumin administration for hypotension management post-plasma exchange:

• Using partial saline replacement (80% albumin/20% saline) during plasma exchange significantly increases the risk of hypotensive reactions compared to 100% albumin (OR: 0.531 for hypotension, OR: 0.140 for moderate-severe hypotension). 4

• However, albumin is NOT superior to normal saline for treating established intradialytic hypotension and does not improve ultrafiltration achievement, time to restore blood pressure, or prevent recurrent hypotension. 2

• Albumin administration may not function as effectively as a volume expander as theoretical oncotic properties would suggest, and it is considerably more expensive than crystalloid alternatives. 3

Recognize age as a risk factor: Older patients have significantly higher risk of hypotensive reactions during and after plasma exchange procedures (OR: 1.017 per year of age). 4

Monitor for symptomatic hypotension requiring immediate treatment: Hypotension should be treated immediately in symptomatic patients to prevent end-organ dysfunction. 1

Transfer to higher level of care may be required if hypotension persists despite initial interventions or if the patient requires multiple vasoactive agents. 1

Monitoring and Escalation

Document clinical neurological examination and hemodynamic parameters before and after plasma exchange procedures. 1

For persistent hypotension despite initial therapy:

• Reassess fluid status and cardiac function using available monitoring tools. 1

• Consider adding additional vasopressor support if single-agent therapy is insufficient. 1

• Evaluate for other causes of hypotension including bleeding, cardiac dysfunction, or citrate toxicity from the procedure. 4