Anemia, transfusions and hospital outcomes among critically ill patients on prolonged acute mechanical ventilation: a retrospective cohort study

Marya D Zilberberg, Lee S Stern, Daniel P Wiederkehr, John J Doyle, Andrew F Shorr, Marya D Zilberberg, Lee S Stern, Daniel P Wiederkehr, John J Doyle, Andrew F Shorr

Abstract

Introduction: Patients requiring prolonged acute mechanical ventilation (PAMV) represent one-third of those who need mechanical ventilation, but they utilize two-thirds of hospital resources devoted to mechanical ventilation. Measures are needed to optimize the efficiency of care in this population. Both duration of intensive care unit stay and mechanical ventilation are associated with anemia and increased rates of packed red blood cell (pRBC) transfusion. We hypothesized that transfusions among patients receiving PAMV are common and associated with worsened clinical and economic outcomes.

Methods: A retrospective analysis of a large integrated claims database covering a 5-year period (January 2000 to December 2005) was conducted in adult patients receiving PAMV (mechanical ventilation for >/= 96 hours). The incidence of pRBC transfusions was examined as the main exposure variable, and hospital mortality served as the primary outome, with hospital length of stay and costs being secondary outcomes.

Results: The study cohort included 4,344 hospitalized patients receiving PAMV (55% male, mean age 61.5 +/- 16.4 years). Although hemoglobin level upon admission was above 10 g/dl in 75% of patients, 67% (n = 2,912) received at least one transfusion, with a mean of 9.1 +/- 12.0 units of pRBCs transfused per patient over the course of hospitalization. In regression models adjusting for confounders, exposure to pRBCs was associated with a 21% increase in the risk for hospital death (95% confidence interval [CI] = 1.00 to 1.48), and marginal increases in length of stay (6.3 days, 95% CI = 5.1 to 7.6) and cost ($48,972, 95% CI = $45,581 to $52,478).

Conclusion: Patients receiving PAMV are at high likelihood of being transfused with multiple units of blood at relatively high hemoglobin levels. Transfusions independently contribute to increased risk for hospital death, length of stay, and costs. Reducing exposure of PAMV patients to blood may represent an attractive target for efforts to improve quality and efficiency of health care delivery in this population.

Figures

Figure 1
Figure 1
Transfusion episodes occurring at each level of pretransfusion hemoglobin among transfused patients on PAMV. Hb, hemoglobin; PAMV, prolonged acute mechanical ventilation.

References

    1. Zilberberg MD, Luippold RS, Sulsky S, Shorr AF. Prolonged acute mechanical ventilation, hospital resource utilization, and mortality in the United States. Crit Care Med. 2008;36:724–730. doi: 10.1097/CCM.0b013e3181691a49.
    1. Zilberberg MD, de Wit M, Pirone JR, Shorr AF. Growth in prolonged acute mechanical ventilation: Implications for healthcare delivery. Crit Care Med. 2008;36:1451–1455. doi: 10.1097/CCM.0b013e3181691a49.
    1. Corwin HL, Gettinger A, Pearl RG, Fink MP, Levy MM, Abraham E, MacIntyre NR, Shabot MM, Duh MS, Shapiro MJ. The CRIT Study: Anemia and blood transfusion in the critically ill – current clinical practice in the United States. Crit Care Med. 2004;32:39–52. doi: 10.1097/01.CCM.0000104112.34142.79.
    1. Rodriguez RM, Corwin HL, Gettinger A, Corwin MJ, Gubler D, Pearl RG. Nutritional deficiencies and blunted erythropoietin response as causes of the anemia of critical illness. J Crit Care. 2001;16:36–41. doi: 10.1053/jcrc.2001.21795.
    1. Vincent JL, Baron JF, Reinhart K, Gattinoni L, Thijs L, Webb A, Meier-Hellmann A, Nollet G, Peres-Bota D. Anemia and blood transfusion in critically ill patients. Jama. 2002;288:1499–1507. doi: 10.1001/jama.288.12.1499.
    1. Levy MM, Abraham E, Zilberberg M, MacIntyre NR. A descriptive evaluation of transfusion practices in patients receiving mechanical ventilation. Chest. 2005;127:928–935. doi: 10.1378/chest.127.3.928.
    1. Gong MN, Thompson BT, Williams P, Pothier L, Boyce PD, Christiani DC. Clinical predictors of and mortality in acute respiratory distress syndrome: potential role of red cell transfusion. Crit Care Med. 2005;33:1191–1198. doi: 10.1097/01.CCM.0000165566.82925.14.
    1. Kahn JM, Caldwell EC, Deem S, Newell DW, Heckbert SR, Rubenfeld GD. Acute lung injury in patients with subarachnoid hemorrhage: incidence, risk factors, and outcome. Crit Care Med. 2006;34:196–202. doi: 10.1097/01.CCM.0000194540.44020.8E.
    1. Shorr AF, Duh MS, Kelly KM, Kollef MH. Red blood cell transfusion and ventilator-associated pneumonia: a potential link? Crit Care Med. 2004;32:666–674. doi: 10.1097/01.CCM.0000114810.30477.C3.
    1. Shorr AF, Jackson WL, Kelly KM, Fu M, Kollef MH. Transfusion practice and blood stream infections in critically ill patients. Chest. 2005;127:1722–1728. doi: 10.1378/chest.127.5.1722.
    1. Zilberberg MD, Carter C, Lefebvre P, Raut M, Vekeman F, Duh MS, Shorr AF. Red blood cell transfusions and the risk of acute respiratory distress syndrome among the critically ill: a cohort study. Crit Care. 2007;11:R63. doi: 10.1186/cc5934.
    1. Plurad D, Martin M, Green D, Salim A, Inaba K, Belzberg H, Demetriades D, Rhee P. The decreasing incidence of late posttraumatic acute respiratory distress syndrome: the potential role of lung protective ventilation and conservative transfusion practice. J Trauma. 2007;63:1–7. discussion 8.
    1. Yilmaz M, Keegan MT, Iscimen R, Afessa B, Buck CF, Hubmayr RD, Gajic O. Toward the prevention of acute lung injury: protocol-guided limitation of large tidal volume ventilation and inappropriate transfusion. Crit Care Med. 2007;35:1660–1666. doi: 10.1097/01.CCM.0000269037.66955.F0. quiz 1667.
    1. Zilberberg MD. Transfusion-attributable acute respiratory distress syndrome, hospital utilization and costs in the united states: a model simulation. Transfus Alternatives Transfus Med. 14 Feb 2008; doi: 10.1111/j.1778-428X.2007.00087.x.
    1. Zilberberg MD, Shorr AF. Effect of a restrictive transfusion strategy on transfusion-attributable severe acute complications and costs in the US ICUs: a model simulation. BMC Health Serv Res. 2007;7:138. doi: 10.1186/1472-6963-7-138.
    1. Corwin HL, Parsonnet KC, Gettinger A. RBC transfusion in the ICU. Is there a reason? Chest. 1995;108:767–771. doi: 10.1378/chest.108.3.767.
    1. Charlson ME, Pompei P, Ales KL, MacKenzie CR. A new method of classifying prognostic comorbidity in longitudinal studies: development and validation. J Chronic Dis. 1987;40:373–383. doi: 10.1016/0021-9681(87)90171-8.
    1. Duan N. Smearing estimate: a nonparametric retransformation method. J Am Stat Assoc. 1983;78:605–610. doi: 10.2307/2288126.
    1. Catlin A, Cowan C, Hartman M, Heffler S, the National Health Expenditure Accounts T National health spending in 2006: a year of change for prescription drugs. Health Aff. 2008;27:14–29. doi: 10.1377/hlthaff.27.1.14.
    1. Heffler S, Smith S, Keehan S, Borger C, Clemens MK, Truffer C. U.S. health spending projections for 2004–2014. Health Aff (Millwood) 2005. pp. W5-74–W75-85.
    1. Centers for Medicare & Medicaid Services . Medicare Provider Analysis and Review (MEDPAR) of Short-stay Hospitals. Baltimore, MD: Centers for Medicare & Medicaid; 2004.
    1. Dasta JF, McLaughlin TP, Mody SH, Piech CT. Daily cost of an intensive care unit day: the contribution of mechanical ventilation. Crit Care Med. 2005;33:1266–1271. doi: 10.1097/01.CCM.0000164543.14619.00.
    1. Hebert PC, Wells G, Blajchman MA, Marshall J, Martin C, Pagliarello G, Tweeddale M, Schweitzer I, Yetisir E. A multicenter, randomized, controlled clinical trial of transfusion requirements in critical care. Transfusion Requirements in Critical Care Investigators, Canadian Critical Care Trials Group. N Engl J Med. 1999;340:409–417. doi: 10.1056/NEJM199902113400601.
    1. Earley AS, Gracias VH, Haut E, Sicoutris CP, Wiebe DJ, Reilly PM, Schwab CW. Anemia management program reduces transfusion volumes, incidence of ventilator-associated pneumonia, and cost in trauma patients. J Trauma. 2006;61:1–5. discussion 5–7.
    1. Claridge JA, Sawyer RG, Schulman AM, McLemore EC, Young JS. Blood transfusions correlate with infections in trauma patients in a dose-dependent manner. Am Surg. 2002;68:566–572.
    1. Taylor RW, Manganaro L, O'Brien J, Trottier SJ, Parkar N, Veremakis C. Impact of allogenic packed red blood cell transfusion on nosocomial infection rates in the critically ill patient. Crit Care Med. 2002;30:2249–2254. doi: 10.1097/00003246-200210000-00012.
    1. Taylor RW, O'Brien J, Trottier SJ, Manganaro L, Cytron M, Lesko MF, Arnzen K, Cappadoro C, Fu M, Plisco MS, Sadaka FG, Veremakis C. Red blood cell transfusions and nosocomial infections in critically ill patients. Crit Care Med. 2006;34:2302–2308. doi: 10.1097/01.CCM.0000234034.51040.7F. quiz 2309.
    1. Gajic O, Rana R, Winters JL, Yilmaz M, Mendez JL, Rickman OB, O'Byrne MM, Evenson LK, Malinchoc M, DeGoey SR, Afessa B, Hubmayr RD, Moore SB. Transfusion-related acute lung injury in the critically ill: prospective nested case-control study. Am J Respir Crit Care Med. 2007;176:886–891. doi: 10.1164/rccm.200702-271OC.
    1. Nathens AB, Nester TA, Rubenfeld GD, Nirula R, Gernsheimer TB. The effects of leukoreduced blood transfusion on infection risk following injury: a randomized controlled trial. Shock. 2006;26:342–347. doi: 10.1097/01.shk.0000228171.32587.a1.
    1. Watkins TR, Rubenfeld GD, Martin TR, Caldwell E, Nathens AB. Effects of leukoreduced blood transfusion on acute lung injury in trauma patients: a randomized controlled trial [abstract] Proc Am Thoracic Soc. 2006;3:A301.

Source: PubMed

3
Tilaa