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Coronavirus | February 2, 2022 | FREE
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Research on CPAP, HFNO, IVIG, and lung transplants for COVID-19

One study found that continuous positive airway pressure (CPAP) outperformed conventional oxygen, but high-flow nasal oxygen (HFNO) did not. Another found no benefit from hyperimmune IV immunoglobulin (IVIG) in hospitalized patients. Two analyses showed good outcomes from lung transplants in COVID-19 patients.


Continuous positive airway pressure (CPAP) reduced the need for intubation in patients with COVID-19 in a trial, published by JAMA on Jan. 24, which offered less certainty about the effectiveness of high-flow nasal oxygen (HFNO). It included 1,273 patients hospitalized in the U.K. They were randomized to CPAP (n=380), HFNO (n=418), or conventional oxygen therapy (n=475). The trial was stopped prematurely. The percentage of patients who died and/or required intubation within 30 days was significantly lower with CPAP than conventional oxygen (36.3% vs. 44.4%; P=0.03). HFNO was not associated with a significant reduction in the composite outcome (44.3% vs. 45.1%; P=0.83). The authors noted that the benefit from CPAP was driven by a reduction in intubation, not mortality, and cautioned that the study may have been underpowered “and early study termination and crossover among the groups should be considered when interpreting the findings.” An accompanying editorial summarized the mixed overall data on these interventions. “Based on the available evidence, it is reasonable to assume that noninvasive ventilation is probably beneficial to reduce the need for invasive mechanical ventilation in patients with COVID-19 who have acute respiratory failure, whereas the precise role of HFNO in patients with COVID-19 is far less clear. For the immediate future, CPAP may be recommended as a first-line therapy with combination HFNO and other hybrid approaches being considered tailored to the patient's condition and tolerance,” the editorial said.

Passive immunotherapy using hyperimmune IV immunoglobulin (hIVIG) from convalescent plasma did not improve outcomes in hospitalized COVID-19 patients, according to an international trial published by The Lancet on Jan. 27. Patients without acute end-organ failure were randomized to either hIVIG (n=301) or saline as placebo (n=292), in addition to remdesivir. At day 7, patients who received hIVIG showed no difference in the primary outcome of clinical improvement compared to the placebo group. Infusion reactions were more common in the hIVIG group (18.6% vs 9.5%), and although the groups were similar on a safety outcome of deaths or adverse events overall, these risks appeared to be increased in patients who received hIVIG and were antibody positive. The authors concluded that SARS-CoV-2 hIVIG did not demonstrate efficacy in the studied patients. “The safety of hIVIG might vary by the presence of endogenous neutralising antibodies at entry,” they added. An accompanying editorial expressed concern about the safety outcome and noted that it will be interesting to see the results from the same study group trying the treatment in outpatients.

Two studies looked at patients who received lung transplants due to COVID-19. A single-center analysis, published by JAMA on Jan. 27, included 30 such patients, all of whom were alive at follow-up about a year later. Compared to 72 patients who received lung transplants for other reasons, they required more transfusions, had longer ICU and hospital stays, and were more likely to require permanent hemodialysis. “Because both the pre- and posttransplant care of patients with COVID-19-associated ARDS is highly complex, expensive, and resource intensive, these patients should preferably undergo lung transplant at high-volume centers with experienced multidisciplinary teams to provide optimal care,” the authors wrote. A research letter in the New England Journal of Medicine, published Jan. 26, looked at 183 transplants due to COVID-19 conducted at centers across the U.S. (out of 3,039 transplants performed). The study had a median follow-up of 1.9 months, during which there were nine postoperative deaths. “Because the 3-month survival among these patients approached that among patients who underwent lung transplantation for reasons other than Covid-19, we believe that lung transplantation may be an acceptable treatment for selected patients with irreversible respiratory failure due to Covid-19,” the authors said.

The omicron variant period has seen unprecedented numbers of COVID-19 cases and hospitalizations but lower severity of illness than in winter 2020 to 2021 or during the delta variant period, according to a study published by MMWR on Jan. 25. It found that with omicron, a maximum of 20.6% of staffed inpatient beds were in use for COVID-19 patients, more than in either comparison period. However, the percentage of hospitalized COVID-19 patients admitted to an ICU during omicron was 13.0%, compared to 18.2% during the winter of 2020-2021 and 17.5% during delta. The use of invasive mechanical ventilation in COVID-19 patients was lowest during omicron (3.5% vs. 7.5% for winter 2020 to 2021 vs. 6.6% for delta), as were in-hospital mortality (7.1% vs. 12.9% vs. 12.3%, respectively) and length of hospital stay (5.5 days vs. 8.0 days vs. 7.6 days, respectively). “COVID-19 disease severity appears to be lower during the Omicron period than during previous periods of high transmission, likely related to higher vaccination coverage, which reduces disease severity, lower virulence of the Omicron variant, and infection-acquired immunity,” the authors wrote. They also noted that by the week ending Jan. 15, ED visits appeared to be decreasing, and the rapid increase in cases and hospital admissions was slowing.

Finally, the American Heart Association and collaborating organizations updated interim guidance on providing cardiac life support to patients with COVID-19. Changes include that the guidance now calls on clinicians to don personal protective equipment before beginning resuscitation, whereas before it recommended initiation of resuscitation be the first priority. An editorial published along with the guidance in Circulation: Cardiovascular and Outcomes on Jan. 24 observed that some frontline clinicians will still make their own decisions in this situation and that the interim guidance will likely change again based on emerging evidence.