While many hospitals had to get creative while dealing with supply-chain issues during the pandemic, the consequences were especially concerning for neonatal intensivists.
A venovenous cannula shortage that began in 2018 affected newborns who required extracorporeal membrane oxygenation (ECMO), the consequences of which were described in a new study in Pediatric Critical Care Medicine. The study shows how the cannula shortage virtually eliminated the venovenous ECMO option for struggling neonates in the United States.
“Our study highlights the particular vulnerability of critically ill neonates to medical device shortages.”
Leon Dupree Hatch, M.D., medical director of the NICU at Monroe Carell Jr. Children’s Hospital at Vanderbilt who led the study, said the results raise an alarm about future supply-chain conditions.
“Our study highlights the particular vulnerability of critically ill neonates to medical device shortages,” Hatch said.
There are two main neonatal ECMO approaches. Venovenous ECMO provides lung support but relies on native heart function, while venoarterial ECMO supports both organs.
As such, venovenous ECMO is less invasive and some data suggest it is associated with lower rates of complications compared with venoarterial ECMO. A large portion of infants who need ECMO only need lung support, Hatch says.
Both venovenous and venoarterial ECMO can be performed using two cannulas, but in venovenous ECMO, surgeons also have the option to use just one: a dual-lumen cannula. The dual-lumen cannula is typically placed in the internal jugular vein. This avoids a second cannula placement in the carotid artery which is required with venoarterial ECMO and can put infants experiencing isolated respiratory failure at undue risk.
No Other Options
In 2018, the FDA announced OriGen Biomedical was recalling its popular dual-lumen cannula, which spurred a nationwide shortage. Surveys show the OriGen cannula was used in 80 percent of venovenous ECMO procedures. At the end of 2019, the company released a statement that the cannula and all of the company’s ECMO products would not be returning to market.
“Few alternatives existed,” Hatch said, noting the main substitute, a bicaval cannula, required advanced imaging for placement.
Neonatal venovenous ECMO cannulas have distinct technical requirements, including a longer length and a larger internal diameter than others commonly used in critical care.
Venovenous ECMO Plummets
To understand how the cannula withdrawal affected patient care in the NICU, Hatch and colleagues analyzed registry data collected by the Extracorporeal Life Support Organization. They evaluated trends in ECMO procedures conducted in neonates less than 29 days old before and after the cannula shortage.
Prior to 2018, 34 percent of registered neonatal ECMO cases were venovenous. After the 2018 withdrawal, this rate fell to 13 percent. By 2021, only five neonatal venovenous ECMO cases were registered in the United States. Venovenous ECMO use fell across all diagnoses evaluated.
“Once centers ran out of their supply of venovenous ECMO cannulas, our data suggests they started switching to venoarterial ECMO for patients who would have normally received the less invasive, venovenous ECMO,” Hatch said.
The venovenous ECMO decline was not seen in adult or pediatric populations, even though these groups also lost access to the venovenous cannula. The researchers attribute this to availability of alternative approaches for larger patients.
“Critically ill infants were particularly vulnerable to changes in their care models due to device availability,” Hatch said.
Survival and Solutions
Despite the reduction in venovenous ECMO use during the shortage, the researchers did not observe significant changes in patient outcomes.
“Thankfully, our data suggest that despite the shortage, survival and short-term neurologic outcomes were unchanged, and families can be reassured by that,” Hatch said.
Still, Hatch says the findings “should spur discussions about policies to incentivize device manufacturers to focus on developing products for critically ill neonates,” which could have global benefit. He noted United Kingdom NICUs were similarly hamstrung by the shortage, with the majority of centers unable to provide venovenous ECMO at all in 2020.
“Despite the shortage, survival and short-term neurologic outcomes were unchanged, and families can be reassured by that.”
Findings from the new study are laying the groundwork.
“Although the impacts of drug shortages are well described in neonates,” the authors wrote, “this study is the first to quantify the potential impact of interruptions in medical device availability.”
In the meantime, the Extracorporeal Life Support Organization, which maintains the data registry used in the study, facilitates a supplies exchange platform to help resources reach those in need.