High-flow oxygen not better than standard O2 in COVID respiratory failure
High-flow oxygen didn't significantly lower death rates beyond those of standard oxygen therapy in COVID-19 patients with respiratory failure, according to a multicenter randomized clinical trial published yesterday in JAMA.
As part of an ongoing trial, researchers enrolled 711 patients who had COVID-19 respiratory failure in 1 of 34 intensive care units (ICUs) in France from January to December 2021, with final follow-up on Mar 5, 2022.
Patients were randomly assigned to receive either high-flow oxygen through a nasal cannula (357 patients) or standard oxygen therapy through a non-rebreathing mask (354) for a median of 4 days. Average patient age was 61 years, and 30% were women.
Death rates at 28 days were 10% in the high-flow oxygen group and 11% in standard oxygen recipients, a non-statistically significant difference. But the intubation rate was significantly lower in high-flow oxygen recipients than in those receiving standard oxygen (45% vs 53%).
The most common adverse event was ventilator-associated pneumonia (58% of the high-flow group vs 53% in standard oxygen recipients).
The authors said that although high-flow oxygen didn't significantly lower the death rate, the reduced risk of intubation and need for invasive mechanical ventilation may be an important outcome. "It may also help avoid the use of ICU ventilators in resource-constrained settings during a pandemic," they wrote.
In a related commentary, Alistair Nichol, PhD, of University College Dublin, and Cecilia O'Kane, PhD, and Daniel McAuley, MD, both of Queen's University Belfast, said that future trials should incorporate different types of COVID-19 patients to determine which subgroups are most likely to benefit or be harmed by the different oxygen therapies.
In the meantime, the results of this study "will provide some reassurance for clinicians in times of reduced availability of certain noninvasive respiratory support strategies during surges in COVID-19 hospitalizations," they wrote. "Particular attention should be given to the potential for complications with each approach, as well as patient preference and tolerance of the selected therapy."
Sep 27 JAMA study and commentary
New blood test aims to predict who will get long COVID
In a small study today in eBioMedicine, researchers from University College London show that a blood sample taken at the time of COVID-19 infection could predict who would develop persistent symptoms up to 1 year later by using precise measurements of proteins.
To conduct the study, the researchers looked at blood plasma samples from 54 British healthcare workers who had a confirmed COVID-19 infection, taken every week for 6 weeks in the spring of 2020. Those samples were compared to samples from 102 healthcare workers who were not infected during the same period.
Using targeted mass spectrometry, the researchers found abnormally elevated levels of 12 proteins out of the 91 studied among those infected by SARS-CoV-2. The degree of protein level elevation correlated to increased symptoms. They found that abnormal levels of 20 proteins, most related to anti-clotting and anti-inflammatory processes, were predictive of persistent symptoms 1 year after infection.
"Our study shows that even mild or asymptomatic Covid-19 disrupts the profile of proteins in our blood plasma," said first author Gabriella Captur, MD, PhD, in a university press release. "This means that even mild Covid-19 affects normal biological processes in a dramatic way, up to at least six weeks after infection."
The authors said a larger, independent study is needed to corroborate these findings. Senior author Wendy Heywood, PhD, said, "If we can identify people who are likely to develop long Covid, this opens the door to trialling treatments such as antivirals at this earlier, initial infection stage, to see if it can reduce the risk of later long Covid."
Sep 28 eBioMedicine study
Sep 28 University College London press release
Texas confirms CWD in Limestone County for first time
Texas officials have confirmed chronic wasting disease (CWD) in Limestone County for the first time, on a farm that breeds captive deer, according to a news release late last week from the Texas Animal Health Commission (TAHC).
Four deer at the facility tested positive for CWD on Sep 5 in tests conducted by the Texas A&M Veterinary Medical Diagnostic Laboratory in College Station. The National Veterinary Services Laboratory in Ames, Iowa, confirmed CWD in two of these samples on Sep 13 and will complete testing of the other two samples soon. Texas Parks and Wildlife Department (TPWD) and TAHC officials have taken steps to secure the facility and notify other breeding operations that received deer or shipped deer to this facility in the past 5 years, the TAHC said.
"TPWD and TAHC are taking this situation very seriously," said John Silovsky, TPWD wildlife director. "Fortunately, these positive cases were detected early, and we have a good sample distribution across the facility.
"At this time, CWD appears to be contained to one pen within the facility. Animal health and wildlife officials will continue to investigate to determine the extent of the disease within the facility and mitigate risks to Texas' CWD susceptible species."
TPWD officials are developing surveillance zone boundaries that may include portions of Limestone, Hill, Freestone, and Navarro counties.
CWD is a fatal prion disease spread between cervids such as deer, moose, and elk through contaminated environments, antler velvet, and body fluids and tissues. Though the disease isn't known to infect humans, some experts fear it one day could cause a disease similar to bovine spongiform encephalopathy ("mad cow disease"). Health officials warn against eating meat from infected animals. The disease has been detected in 30 US states.
Sep 23 TAHC news release