Lincoln Hospital has been at forefront of this outbreak and has cared for several patients with suspected/ confirmed H1N1 virus in the South-Bronx Area in NY. We report on patient characteristics of critically ill patients admitted with ILI.
A prospective chart review of all adult patients with ILI with laboratory evidence of probable or confirmed H1N1 admitted between May1st and July30th 2009 was performed. Probable cases include either Influenza-A Antigen positive or Novel-H1N1 PCR positive patients while confirmed cases include patients with both tests positive.
15 among 47 hospitalized patients met above inclusion criteria and were admitted to the ICU. Average APACHE-II score was 31. Only 5 patients were older than 65 years(median-age: 49.5,Range: 22-79). 3patients did not report fevers, but all patients had respiratory complaints. 4 among the 5 patients who did not have previous co-morbidity had a BMI > 26. 9/15 patients were overweight with a median BMI of 33.5 among overweight subjects. Lymphopenia was noted in 10/15 patients and elevated CPK was noted in 7/15 with a median of 563. 7 had LDH values out of proportion to CPK elevation(median of 362 among all subjects). 4 patients had normal radiographs on admission, alveolar consolidation(07), interstitial infiltrates (02) and nodular infiltrates (02). Only 3/ 15 tested positive for influenza-A antigen on the nasopharyngeal(NP) swab while the remaining 12 tested positive for the antigen on bronchial washings or tracheal aspirates. Novel-H1N1 PCR was tested in 8/15 patients and 6 were positive.12 patients were mechanically ventilated and 9 patients had more than 1 organ failure. Average LOS was 9.6 days with an observed mortality of 26% (04).CONCLUSIONS: H1N1 can lead to significant morbidity and mortality among critically ill patients. Antigen testing on the NP-swab is insensitive and a lower respiratory-tract specimen should be obtained when feasible.
This is first series to describe the characteristics of ICU patients with H1N1 virus in the US.