A hat tip to Crof over at Crofsblog for finding this report in the Barcelona Reporter about a study, published on Friday in the journal Critical Care, that examines the risk factors of 32 ICU patients admitted for pandemic influenza.
First the news story, then the abstract to the paper.
About half of people admitted to ICU in hospitals for severe complications of influenza A had no risk factor or disease, according to a study conducted in 21 Spanish hospitals.
Study involving 21 Spanish hospitals states 50% of swine flu, ICU patients had no previous health problems
The study, presented on the website of the medical journal ‘Critical Care’ is the largest ever conducted in Europe on influenza cases requiring intensive care. Their findings contradict one of the messages on influenza A released by the Ministry of Health and the Department of Health, which have repeatedly reported that patients with influenza A cases had previous health problems.
The findings contain important messages for both the general population and for health authorities and medical intensivists. For the general population, an appeal to healthy people without risk factors to avoid falling prey to overconfidence in regard to influenza A. Although the vast majority of those affected will overcome the flu without complications, a small percentage will have pneumonia and should be hospitalized.
Over the summer many countries have repeated the mantra that those who are experiencing severe illness nearly all have underlying medical conditions. Apparently they feel this is a reassuring message.
Over and over, of course, we’ve seen reports to the contrary.
While underlying conditions might put you at greater risk, previously healthy individuals are seeing bad outcomes with this virus as well. Once again, this study raises questions about obesity being an underlying factor – a theory that has fallen in and out of favor several times over the past few months.
The good news is, those who are seriously impacted by this virus remain a very small percentage of the total infected.
Intensive care adult patients with severe respiratory failure caused by Influenza A (H1N1)v in Spain
Jordi Rello , Alejandro Rodriguez , Pedro Ibanez , Lorenzo Socias , Javier Cebrian , Asuncion Marques, Jose Guerrero, Sergio Ruiz-Santana , Enrique Marquez , Frutos del Nogal-Saez , Francisco Alvarez-Lerma , Sergio Martinez , Miquel Ferrer , Manuel Avellanas , Rosa Granada , Enrique Maravi-Poma , Patricia Albert , Rafael Sierra , Loreto Vidaur , Patricia Ortiz , Isidro Prieto del Portillo , Beatriz Galvan , Cristobal Leon-Gil and The H1N1 SEMICYUC working group
Critical Care 2009, 13:R148doi:10.1186/cc8044
11 September 2009
Patients with influenza A (H1N1)v infection have developed rapidly progressive lower respiratory tract disease resulting in respiratory failure. We describe the clinical and epidemiologic characteristics of the first 32 persons reported to be admitted to the intensive care unit (ICU) due to influenza A (H1N1)v infection in Spain.
Illness onset of the 32 patients occurred between June 23 and July 31, 2009. The median age was 36 years (IQR = 31 - 52).
Ten (31.2%) were obese, 2 (6.3%) pregnant and 16 (50%) had pre-existing medical complications.
Twenty-nine (90.6%) had primary viral pneumonitis, 2 (6.3%) exacerbation of structural respiratory disease and 1 (3.1%) secondary bacterial pneumonia.
Twenty-four patients (75.0%) developed multiorgan dysfunction, 7 (21.9%) received renal replacement techniques and 24 (75.0%) required mechanical ventilation. Six patients died within 28 days, with two additional late deaths. Oseltamivir administration delay ranged from 2 to 8 days after illness onset, 31.2% received high-dose (300mg/day), and treatment duration ranged from 5 to 10 days (mean 8.0 + 3.3).
Over a 5-week period, influenza A (H1N1)v infection led to ICU admission in 32 adult patients, with frequently observed severe hypoxemia and a relatively high case-fatality rate. Clinicians should be aware of pulmonary complications of influenza A (H1N1)v infection, particularly in pregnant and young obese but previously healthy persons.