Newborns who received hemofiltration had a significantly shorter duration of ECMO (P=0.02) and spent less time on mechanical ventilation after stopping ECMO (P=0.04) than those who did not receive hemofiltration, according to Dick Tibboel, M.D., Ph.D., of the Erasmus Medical Center Sophia Children's Hospital in Rotterdam, The Netherlands.
In addition, there was less need for blood transfusions (P<0.001).
Dr. Tibboel and colleagues reported their findings online in Critical Care.
In real life, the advantages they found translated into savings of about 5,000 Euros ($6,600) per ECMO run, the researchers said.
ECMO is a supportive cardiopulmonary bypass technique used in patients with acute reversible cardiovascular or respiratory failure, according to the researchers.
Previous studies have shown hemofiltration to be beneficial during cardiopulmonary bypass, so the researchers set out to see whether it could also improve outcomes from ECMO.
They compared outcomes from 15 patients who received continuous veno-venous hemofiltration during ECMO and 46 controls who received ECMO only.
All patients were younger than 28 days (median about 2 days). Those who received hemofiltration started the treatment within three hours of initiating ECMO.
The two groups were generally well matched for baseline illness severity. The most common reasons for treatment in the NICU were congenital diaphragmatic hernia, which was more frequent in the controls, and meconium aspiration syndrome.
Other reasons included respiratory distress syndrome, viral or bacterial pneumonia, congenital cystic adenomatoid malformation of the lung, persistent pulmonary hypertension, postcardiac surgery, and sepsis.
The researchers identified several outcomes that were improved by adding hemofiltration. They included:
- Shorter time on ECMO (98 versus 126 hours, P=0.02)
- Shorter time on mechanical ventilation after ECMO (2.5 versus 4.8 days, P=0.04)
- Fewer blood transfusions (0.9 versus 1.8 mL/kg/day, P<0.001)
- Lower fluid balance per day (29 versus +40 mL/kg/day, P<0.001)
- Lower maximum serum urea (4 versus 6 mmol/L, P=0.01)
Researchers speculated that hemofiltration alleviated some of the systemic inflammatory effects and complications of ECMO, including capillary leakage syndrome.
There was no significant difference in the mortality rate (16% in the controls versus 21% in the cases, P=0.61), but the researchers said the numbers of patients were too small to draw any definitive conclusions.
Because the personnel who run ECMO are also trained to run hemofiltration, there were no additional staffing costs associated with adding the treatment.
Taking into consideration the need for fewer blood transfusions and shorter duration of ECMO, a facility that has 30 patients who require ECMO per year could save about 150,000 Euros ($198,000) a year by adding hemofiltration, the researchers said.
The findings are being confirmed in an ongoing randomized controlled trial, they said.
The team acknowledged some limitations of the study, including the small sample size, inability to perfectly match the cases and controls on illness severity, the fact that the cases and controls were treated during two different two-year periods, and the lack of information on inflammatory mediators.
|The authors reported no conflicts of interest.|
Zalman S. Agus, MD Emeritus Professor
University of Pennsylvania School of Medicine