How to manage pulmonary complications with scrub typhus?

Question

Hello doctor,

My wife contracted a severe infection while researching coral reefs. Initially, it seemed like severe malaria, but it has now been confirmed as scrub typhus with acute respiratory distress syndrome (ARDS). She developed severe pulmonary hemorrhage and needed mechanical ventilation with prone positioning. She started Doxycycline but is now developing serotonin syndrome due to interactions with her depression medications. Her recent diving history is complicating respiratory management. Two of her research assistants have developed similar lung issues. Should we consider extracorporeal membrane oxygenation? What are the risks of barotrauma with severe lung injury? Also, there are increasing signs of right heart failure, and recent imaging suggests possible pulmonary hypertension.

Kindly help.

Answer 1

Hello,

Welcome to icliniq.com.

I understand your concern.

Your wife’s condition is very serious, and ECMO (extracorporeal membrane oxygenation) should definitely be considered. ECMO is often used for severe ARDS (acute respiratory distress syndrome) that does not respond to regular ventilation, especially when the pulmonary fibrosis ratio is less than 80, despite using low tidal volume, prone positioning, and high PEEP.

There are two types of ECMO: veno-venous (VV) and veno-arterial (VA). VV ECMO (venovenous extracorporeal membrane oxygenation) is used for respiratory failure only, while VA ECMO (venoarterial extracorporeal membrane oxygenation) may be needed if right heart failure worsens.

It is important to remember that ECMO does not cure the problem, it just supports the lungs. Managing the ongoing hemorrhage is the main priority, and you may need to use systemic anticoagulants.

You are right to be concerned about barotrauma. High PEEP and aggressive ventilation can worsen hemorrhage and cause barotrauma. To minimize this risk, consider these strategies:

Use ultra-low tidal volume ventilation.
Keep driving pressure below 15 cm H2O (centimeters of water).
Continue the prone position.
Carefully manage fluid balance to prevent pulmonary edema and reduce strain on the heart.
Use pulmonary vasodilators to help manage right heart failure and pulmonary hypertension.
Perform a bedside echo to assess cardiac function.

Doxycycline itself does not cause serotonin syndrome, but it interacts with antidepressants. Immediately stop the antidepressants, and consider using Cyproheptadine if serotonin syndrome is severe.

If Doxycycline cannot continue, you might want to switch to Azithromycin and Rifampin.

Her past hyperbaric exposure could increase the risk of barotrauma, so be sure to rule out decompression sickness before using mechanical ventilation. Optimize the ventilation settings to minimize barotrauma.

Also, it is important to investigate environmental or toxin-related exposures urgently, as her colleagues are also infected.

I hope you are satisfied with my answer. For further queries, you can consult me at iCliniq.

Thank you.