Individualized ventilation in influenza A (H1N1) infection: The experience of a single intensive care unit
More details
Hide details
Pneumonologist, Intensive Care Physician, Intensive Care Unit, Heraklion University General Hospital
Pneumonologist, Intensive Care Physician, ICU Registrar A, ICU, Heraklion University General Hospital
Pneumonologist, Intensive Care Physician, ICU Registrar A, ICU, Heraklion University General Hospital
Pneumonologist, Intensive Care Physician, Assistant Professor of Intensive Care Medicine, ICU, Heraklion University General Hospital, Medical School, University of Crete, Heraklion
Physician-Intensive Care Physician, ICU Registrar Β, ICU, Heraklion University General Hospital
ICU Director, Professor of Intensive Care Medicine, ICU, Heraklion University General Hospital, Medical School, University of Crete, Heraklion, Crete
Corresponding author
Dimitris Georgopoulos   

ICU, University General Hospital of Heraklion, University of Crete P.O. Box 1352, 71110 Heraklion Greece
Pneumon 2012;25(2):228-236

• Although ALI/ARDS associated with H1N1 infection usually affects young, previously healthy individuals, it is often severe leading to prolonged ICU stay • Reported mortality rates in ICU patients differ substantially between centres • Efforts to avoid the development of VILI appear to play an important role in the course of the disease • Even in the most severe forms of ARDS, the application of non conventional strategies (oesophageal pressure measurement, HFOV, ECCO2-R) to individualize treatment might lead to a favourable outcome

Severe influenza A infection (H1N1) is associated with acute respiratory failure the management of which challenges intensive care unit (ICU) physicians. The clinical features and outcome of all patients with laboratory-confirmed H1N1 admitted to the Heraklion University Hospital adult ICU during the last two years are reported.

A retrospective observational single centre study was conducted at a tertiary ICU. The medical records of all patients admitted to the ICU with H1N1 infection 10th July 2009 - 1st May 2011 were reviewed. The data collected included demographic characteristics of the patients, the clinical manifestations and illness severity assessed by the Acute Physiology and Chronic Health Evaluation (APACHE) II, and interventions and complications during the ICU stay. The duration of mechanical ventilation, the length of ICU stay and the 60 day mortality were used as outcome indices.

During the study period 23 patients with H1N1 were admitted to the ICU. They were relatively young (median age 39 yrs) with a median APACHE II on admission of 12 (range 5-22). In 7 patients (30.4%) there were no comorbidities on admission. In all cases the reason for admission was acute respiratory failure, with a median PaO2/FiO2 128 mmHg (range 83-376). Acute lung injury/ acute respiratory distress syndrome (ALI/ARDS) was the cause of respiratory failure in 21 patients (91.3%), while 2 presented with acute exacerbation of chronic obstructive pulmonary disease (COPD). Twenty patients (87%) required mechanical ventilation; 10 invasive, 5 non invasive and 5 both. Non conventional ventilator management, including oesophageal balloon insertion, high frequency oscillatory ventilation (HFOV), extracorporeal CO2 removal (ECCO2-R) and prone positioning were applied in 8 patients (34.8%). The median duration of mechanical ventilation and median length of ICU stay were 11.6 and 18.6 days, respectively. One patient died (4.3 % mortality).

The necessity for non conventional ventilator strategies and the prolonged need for life support characterize the severity of ARDS associated with H1N1 infection. An individualized ventilator approach, based on the principles of lung protective ventilation may have a significant influence on the course of the disease.

APACHE, acute physiology and chronic health evaluation; ALI, acute lung injury; ARDS, acute respiratory distress syndrome; COPD, chronic obstructive pulmonary disease; HFOV, high frequency oscillatory ventilation; ECCO2-R, extracorporeal CO2 removal; rRT-PCR, real-time reverse transcriptase polymerase chain reaction; AKI, acute kidney injury; CDC, Centers for Disease Control and Prevention; BMI, body mass index; NIMV, non invasive mechanical ventilation; Pplat, static end-inspiratory plateau pressure; PEEP, positive end expiratory pressure; FiO2, inspired fraction of oxygen; Plend, transpulmonary pressures at end-expiration; Plins, transpulmonary pressure at end-inspiration; RRT, renal replacement therapy; PL, transpulmonary pressure; VT, volume tidal; ΔP, delta pressure; BAL, bronchoalveolar lavage; ALL, acute lymphocyte leukemia; AF, atrial fibrillation; HC, hypertrophic cardiomyopathy; CAD, coronary artery disease; MM, multiple myeloma; AECOPD, acute exacerbation of chronic obstructive pulmonary disease; VILI, ventilator induced lung injury; MV, mechanical ventilation.
The authors would like to thank all members of the adult Intensive Care Unit staff at the University Hospital of Heraklion who, through their tireless and skillful efforts substantially contributed to the favourable outcome of this complex disease in these patients.
The authors have no competing interest to disclose.
EA developed the study design and carried out the data collection, data analysis, manuscript draft and revision. NX contributed with critical manuscript revisions. GP contributed with critical manuscript revisions. EK carried out data collection and manuscript revision. EA contributed with manuscript revision. DG brought up the study idea and carried out critical manuscript revision. All authors have read and approved the manuscript for publication.
Perez-Padilla R, de la Rosa-Zamboni D, Ponce de Leon S, et al; INER Working Group on Influenza. Pneumonia and respiratory failure from swine-origin influenza A (H1N1) in Mexico. N Engl J Med 2009, 361:680-689.
Department of Epidemiological Surveillance and Intervention, Hellenic Centre for Disease Control and Prevention, Athens, Greece. www.keelpno.gr.
Knaus WA, Draper EA, Wagner DP, Zimmerman JE. APACHE II: a severity of disease classification system. Crit Care Med 1985, 13:818-829.
Bernard GR, Artigas A, Brigham KL, et al. The American-European Consensus Conference on ARDS: Definitions, mechanisms, relevant outcomes and clinical trial coordination. Am J Respir Crit Care Med 1994, 149:818-824.
Horan TC, Andrus M, Dudeck MA: CDC/NHSN Surveillance definition of health care-associated infection and criteria for specific types of infections in the acute care setting. Am J Infect Control 2008, 36:309-332.
Mehta RL, Kellum JA, Shah SV, et al. Acute Kidney Injury Network: report of an initiative to improve outcomes in acute kidney injury. Crit Care 2007, 11:R31.
Antonelli M, Levy M, Andrews PJ, et al: Hemodynamic monitoring in shock and implications for management. Intensive Care Med 2007, 33: 575-590.
Mandell LA, Wunderink RG, Anzueto A, et al. Infectious Diseases Society of America/American Thoracic Society consensus guidelines on the management of community-acquired pneumonia in adults. Clinical Infectious Diseases 2007, 44:S27–72.
ATS. Guidelines for the management of adults with hospitalacquired, ventilator associated and health care associated pneumonia. Am J Respir Crit Care Med 2005, 171:388-416.
Meduri GU, Annane D, Chrousos GP, Marik P, Sinclair SE. Activation and Regulation of Systemic Inflammation in ARDS: Rationale for Prolonged Glucocorticoid Therapy. Chest 2009, 136:1631-143.
ANZIC Influenza Investigators, Webb SA, Pettilä V, Seppelt I, et al: Critical Care Services and 2009 H1N1 influenza in Australia and New Zealand. N Engl J Med 2009, 361:1925-1934.
Rello J, Rodríguez A, Ibañez P, et al; H1N1 SEMICYUC Working Group. Intensive care adult patients with severe respiratory failure caused by influenza A (H1N1) in Spain. Crit Care 2009, 13:R148.
Jain S, Kamimoto L, Bramley AM, et al; 2009 Pandemic Influenza A (H1N1) Virus Hospitalizations Investigation Team. Hospitalized patients with 2009 H1N1 influenza in the United States, April-June 2009. N Engl J Med. 2009, 361:1935-1944.
Louie JK, Acosta M, Winter K, et al; California Pandemic (H1N1) Working Group. Factors associated with death or hospitalization due to pandemic 2009 influenza A (H1N1) infection in California. JAMA 2009, 302:1896-1902.
Domínguez-Cherit G, Lapinsky SE, Macias AE, et al. Critically ill patients with 2009 influenza A (H1N1) in Mexico. JAMA 2009, 302:1880-1887.
Kumar A, Zarychanski R, Pinto R, et al; Canadian Critical Care Trials Group H1N1 Collaborative: Critically ill patients with 2009 influenza A (H1N1) infection in Canada. JAMA 2009, 302:1872-1879.
Estenssoro E, Ríos FG, Apezteguía C, et al; Registry of the Argentinian Society of Intensive Care SATI. Pandemic 2009 influenza A in Argentina: a study of 337 patients on mechanical ventilation. Am J Respir Crit Care 2010, 182:41-48.
Grasselli G, Bombino M, Patroniti N, et al. Management of acute respiratory complications from influenza A (H1N1) infection: experience of a tertiary-level Intensive Care Unit. Minerva Anestesiol 2011, 77:1-8.
Martin-Loeches I, Papiol E, Rodríguez A, et al; the H1N1 SEMICYUC Working Group. Acute kidney injury in critical ill patients affected by influenza A (H1N1) virus infection. Crit Care 2011, 15:R66.
Brandsaeter BJ, Pillgram M, Berild D, Kjekshus H, Kran AM, Bergersen BM. Hospitalised patients with suspected 2009 H1N1 Influenza A in a hospital in Norway, July - December 2009. BMC Infect Dis 2011, 11:75.
Nin N, Lorente JA, Soto L, et al. Acute kidney injury in critically ill patients with 2009 influenza A (H1N1) viral pneumonia: an observational study. Intensive Care Med 2011, 37:768–774.
Sood MM, Rigatto C, Zarychanski R, et al. Acute kidney injury in critically ill patients with 2009 pandemic influenza A (H1N1): report from a Canadian Province. Am J Kidney Dis 2010, 55:848-55.
Nin N, Soto L, Hurtado J, et al. Clinical characteristics and outcomes of patients with 2009 influenza A(H1N1) virus infection with respiratory failure requiring mechanical ventilation. J Crit Care 2011, 26:186-192.
Teke T, Coskun R, Sungur M, et al. 2009 H1N1 influenza and experience in three critical care Int J Med Sci 2011, 8:270-277.
Fuhrman C, Bonmarin I, Bitar D, et al. Adult intensive-care patients with 2009 pandemic influenza A(H1N1) infection. Epidemiol Infect 2010, 26:1-8.
Rana S, Jenad H, Gay PC, Buck CF, Hubmayr RD, Gajic O. Failure of non-invasive ventilation in patients with acute lung injury: observational cohort study. Crit Care 2006, 10:R79.
Pneumatikos I. Acute respiratory failure: To intubate or not to intubate? Think about Noninvasive Ventilation! Pneumon 2011, 24:136-141.
Antonelli M, Conti G, Esquinas A, et al. A multiple-center survey on the use in clinical practice of noninvasive ventilation as a first-line intervention for acute respiratory distress syndrome. Crit Care Med 2007, 35:18-25.
Hager DN, Krishnan JA, Hayden DL, Brower RG; ARDS Clinical Trials Network. Tidal volume reduction in patients with acute lung injury when plateau pressures are not high. Am J Respir Crit Care Med 2005, 172:1241-1245.
Terragni PP, Rosboch G, Tealdi A, et al. Tidal hyperinflation during low tidal volume ventilation in acute respiratory distress syndrome. Am J Respir Crit Care Med 2007, 175:160-166.
Bellani G, Guerra L, Musch G, et al. Lung regional metabolic activity and gas volume changes induced by tidal ventilation in patients with acute lung injury. Am J Respir Crit Care Med 2011, 183:1193-1199.
Talmor D, Sarge T, Malhotra A, et al. Mechanical ventilation guided by esophageal pressure in acute lung injury. N Engl J Med 2008, 359:2095-2104.
Fessler HE, Derdak S, Ferguson ND, et al. A protocol for highfrequency oscillatory ventilation in adults: results from a roundtable discussion. Crit Care Med 2007, 35:1649-1654.
Sedeek KA, Takeuchi M, Suchodolski K, Kacmarek RM. Determinants of tidal volume during high-frequency oscillation. Crit Care Med 2003, 31:227-231.
Fessler HE, Hager DN, Brower RG. Feasibility of very high frequency ventilation in adults with acute respiratory distress syndrome. Crit Care Med 2008, 36:1043-1048.
Hager DN, Fessler HE, Kaczka DW, et al. Tidal volume delivery during high frequency oscillatory ventilation in adults with acute respiratory distress syndrome. Crit Care Med 2007, 35:1522-1529.
Terragni PP, Del Sorbo L, Mascia L, et al: Tidal volume lower than 6 ml/kg enhances lung protection: role of extracorporeal carbon dioxide removal. Anesthesiology 2009, 111:826-835.
Journals System - logo
Scroll to top