RRT Can Play a Critical Role in Treating Ebola Patients

Recent Ebola cases have shown that dialysis can play a key role in the survival of critically ill patients. Given the potential importance of renal replacement therapy (RRT) for these patients—and the need for biocontainment procedures to protect caregivers—nephrologists should take active roles in creating treatment plans at their facilities, experts said.

The recovery of a patient at Emory University Hospital shows that even patients at the point of organ failure can recover from Ebola virus disease if given aggressive supportive therapy, according to Harold A. Franch, MD, a nephrologist who helped treat this first Ebola patient known to have received RRT. Franch presented this case study at a special session at Kidney Week as well as in a recent article in the Journal of the American Society of Nephrology.

“Now we know that you can recover kidney function, so the damage is not irreversible,” Franch said. Supportive therapy—especially fluid replacement—can buy the time needed for a patient’s body to mount an immune response to overcome the viral attack, at least in some cases.

Ebola has several effects that can lead to acute kidney injury (AKI) and the need for RRT. These effects include massive fluid loss from vomiting and diarrhea leading to hypovolemia, a systemic inflammatory response syndrome, hemorrhagic fever and clotting abnormalities that increase susceptibility to bleeding, and more, said Sarah Faubel, MD, professor of medicine at the University of Colorado, Denver, and head of ASN’s AKI Advisory Group. Faubel also spoke at the Kidney Week special session. “The medical indications for renal replacement therapy in Ebola virus are similar to those in other patients with acute kidney injury, and involve considerations such as volume control, electrolyte balance, and the severity of kidney dysfunction,” Faubel said. “In critically ill patients, nephrologists have great experience in considering the risks and benefits of RRT, and the medical decision to start it should follow the usual course.”

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The decision may follow standard considerations, but the implementation is different because of the need to isolate the patient. A unique aspect of Ebola treatment is that staff protection is as important as the patient outcome. “You will not succeed unless you have an isolation environment that protects your staff safety and the safety of the community,” Franch said.

“The biggest lesson in terms of treatment of Ebola patients is that you have to play by the rules of the isolation unit,” Franch told Kidney News. “When you are in an operating room, you have to do everything according to operating room standards to protect the patient. When you are in an isolation room, you have to do everything according to isolation procedures to protect the staff from infection.”

A hospital should develop its plan for dealing with an Ebola patient well before any patient arrives. These plans should follow Centers for Disease Control and Prevention (CDC) guidelines and local community health department recommendations, Faubel said. “Given the potential need for dialysis and the complexity of performing dialysis in patients with Ebola virus disease (EVD), nephrologist involvement is essential in the planning phases of hospitals intending to care for patients with EVD,” a guidance document developed by ASN recommends. The plan should address questions such as the use of anticoagulation, an approach for laboratory testing, and how to handle dialysis effluent and the other medical wastes. (Many of these treatment resources can be found online—see sidebar.)

For effective planning, nephrologists need a realistic idea of the infectivity of the virus. Ebola virus is spread through direct contact with blood from infected patients, but can also spread via contact with other fluids such as urine, sweat, vomit, and diarrhea.

Franch said that Ebola is more like hepatitis B than HIV: “It can survive on surfaces about as long as hepatitis B, which isn’t that long, but is long enough. It is not like HIV, which dies pretty much as soon as it gets on a surface. Ebola is a lipid-coated virus, so once you really dry it out, it dies. In a dialysis unit, you have to isolate hepatitis B patients, but you don’t have to isolate HIV patients.”

One factor that makes Ebola so infectious is its very high levels—in the billions of viruses per milliliter of blood—and it can also be present on the patient’s skin. It is not transmitted through the respiratory route like influenza, but aerosolized bodily fluids are infectious. These characteristics call for extra caution in dialysis set-up, and argue for the use of continuous RRT to minimize blood spill possibilities.

The case of Thomas Eric Duncan in Dallas, in which two nurses treating him became infected, led the CDC to tighten its guidelines to recommend that personal protective equipment have full body coverage for all workers caring for Ebola patients.

The Emory team adopted procedures designed to minimize the possibility of healthcare worker exposure. “We dedicated a pressure-controlled room, used point-of-care laboratory testing, [and used] dedicated ultrasound and x-ray machines that never left the room. Blood cultures were performed in the room and consulting physicians did not enter the room unless absolutely required,” Franch said.

Much of the care relied on ICU nurses with specialized training in isolation protocols and in continuous RRT who volunteered for the duty, but some on-the-spot training was unavoidable. They followed isolation procedures such as checking the integrity of the protective gear of those entering and exiting the isolation unit.

The team used a single dialysis machine “with a small footprint that could stay in the room and had the flexibility to perform both continuous and intermittent modes of dialysis,” Franch said, and anything that went into the isolation unit stayed there.

In keeping with Kidney Disease Improving Global Outcomes AKI guidelines, the team put the cannula in the right internal jugular, which is their local practice. Line placement is considered a center-specific consideration, and hospitals should stick with practices they have experience with. This is no time to experiment with new procedures, Faubel said.

Franch said that to minimize filter changes in the dialysis unit, the patient received anticoagulation therapy, which has its own problems because Ebola is a hemorrhagic disease. “For this reason, we used regional citrate anticoagulation with peripheral calcium replacement and regular ionized calcium measurements. While this approach worked extremely well, alkalosis from metabolism of the citrate does become a problem,” Franch said.

Emory University Hospital successfully treated a pair of other patients whose kidney function remained normal despite arriving from Africa on day 10 and day 14 of their illnesses. The RRT patient was admitted much earlier, on day 4 of his disease, and developed AKI despite the aggressive supportive therapy. Some observers have doubted whether continued treatment could work when the disease has progressed this far. But with RRT and other support, the patient’s immune system responded. “The biggest lesson is that someone can recover from this,” Franch concluded.

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