PURPOSE: The 2009 influenza A virus, H1N1 has caused unusually severe pneumonia and fulminate respiratory failure requiring extraordinary life saving methods. The objective of our study is to describe baseline characteristics, treatment measures, and outcomes of consecutive critically ill patients admitted for 2009 Influenza A H1N1 pneumonia at Upstate Medical University Medical Intensive Care Unit.
METHODS: Observational retrospective study of 9 critically ill patients with 2009 influenza A H1N1-related critical illness. The primary outcome measure was mortality. The secondary outcome was rate of conventional mechanical ventilation and employment of extraordinary life-sustaining measures such as high frequency oscillatory ventilation (HFO) and extracorporeal membrane oxygenation (ECMO).
RESULTS: There were 9 patients admitted to the Medical Intensive Care Unit between October and December 2009 for H1N1 pneumonia. Age: median 41 years (range: 21-64 years). Sex:8 females and 1 male; BMI: median 29.1 kg/m2 (range: 20.4-61 kg/m2); Apache score on admission: median 13 (range: 8-20) and a mean of 13.5. All patients had respiratory failure requiring mechanical ventilation. Four patients failed conventional ventilation and HFO was initiated. Time on conventional ventilation: median 21.5 hours (range 9-1296 hours); time on HFO: 176 hours (range 128-480 hours). Two patients had multiple organ system dysfunction, but 7 patients had only respiratory failure. Of the 4 patients on HFO one had worsening hypoxemia and was maintained on ECMO for 7 days. Only one death occurred in the HFO group. The rest of patients including the one on ECMO, survived to discharge.
CONCLUSION: Our group of patients was remarkable in that the ARDS (Acute Respiratory Distress Syndrome) from influenza H1N1 pneumonia was unusually severe, however, they had a fairly good survival and functional status at discharge despite requiring extraordinary life sustaining measures for prolonged periods of time.
CLINICAL IMPLICATIONS: The role of HFO in ARDS due to H1N1 pneumonia is still not established but our observational study and others of similar nature suggest an impact on survival in this subset of patients.
DISCLOSURE: Pranav Singh, No Financial Disclosure Information; No Product/Research Disclosure Information