Tuberc Respir Dis.  2012 Oct;73(4):224-230.

Prognostic Factors of Patients Requiring Prolonged Mechanical Ventilation in a Medical Intensive Care Unit of Korea

• Kim MH
• Cho WH
• Lee K
• Kim KU
• Jeon DS
• Park HK
• Kim YS
• Lee MK
• Park SK

Abstract

BACKGROUND
We evaluated the clinical outcomes and prognostic factors of patients requiring prolonged mechanical ventilation (PMV), defined as ventilator care for > or =21 days, who were admitted to the medical intensive care unit (ICU) of a university hospital in Korea.
METHODS
During the study period, a total of 2,644 patients were admitted to the medical ICU, and 136 patients (5.1%) were enrolled between 2005 and 2010.
RESULTS
The mean age of the patients was 61.3+/-14.5 years, and 94 (69.1%) were male. The ICU and six-month cumulative mortality rates were 45.6 and 58.8%, respectively. There were 96 patients with tracheostomy placement after admission and their mean period from admission to the day of tracheostomy was 21.3+/-8.4 days. Sixty-three patients (46.3%) were successfully weaned from ventilator care. Of the ICU survivors (n=74), 34 patients (45.9%) were transferred to other hospitals (not university hospitals). Two variables (thrombocytopenia [hazard ratio (HR), 1.964; 95% confidence interval (CI), 1.225~3.148; p=0.005] and the requirement for vasopressors [HR, 1.822; 95% CI, 1.111~2.986; p=0.017] on day 21) were found to be independent factors of survival on based on the Cox proportional hazard model.
CONCLUSION
We found that patients requiring PMV had high six-month cumulative mortality rates, and that two clinical variables (measured on day 21), thrombocytopenia and requirement for vasopressors, may be associated with prognostic indicators.

Keyword

Ventilators, Mechanical; Intensive Care Units; Korea

MeSH Terms

Humans
Critical Care
Intensive Care Units
Korea
Male
Respiration, Artificial
Survivors
Thrombocytopenia
Tracheostomy
Ventilators, Mechanical

Figure

• 

  Figure 1 Flow chart of the clinical outcome of total enrolled patients. ICU: intensive care unit.

• 

  Figure 2 Survival curves according to the requirement for vasopressor and thrombocytopenia on day 21 for patients requiring prolonged mechanical ventilation. (A) Requirement for vasopressor or not (log rank, 7.26; p=0.007). (B) Thrombocytopenia or not (log rank, 11.27; p=0.008).

Reference

1. Nelson JE, Cox CE, Hope AA, Carson SS. Chronic critical illness. Am J Respir Crit Care Med. 2010. 182:446–454.

2. Cox CE, Carson SS, Lindquist JH, Olsen MK, Govert JA, Chelluri L, et al. Differences in one-year health outcomes and resource utilization by definition of prolonged mechanical ventilation: a prospective cohort study. Crit Care. 2007. 11:R9.

3. Carson SS, Garrett J, Hanson LC, Lanier J, Govert J, Brake MC, et al. A prognostic model for one-year mortality in patients requiring prolonged mechanical ventilation. Crit Care Med. 2008. 36:2061–2069.

4. Lone NI, Walsh TS. Prolonged mechanical ventilation in critically ill patients: epidemiology, outcomes and modelling the potential cost consequences of establishing a regional weaning unit. Crit Care. 2011. 15:R102.

5. Hung MC, Lu HM, Chen L, Hu FC, Chan SY, Yan YH, et al. Life expectancies and incidence rates of patients under prolonged mechanical ventilation: a population-based study during 1998 to 2007 in Taiwan. Crit Care. 2011. 15:R107.

6. Unroe M, Kahn JM, Carson SS, Govert JA, Martinu T, Sathy SJ, et al. One-year trajectories of care and resource utilization for recipients of prolonged mechanical ventilation: a cohort study. Ann Intern Med. 2010. 153:167–175.

7. Wu YK, Tsai YH, Lan CC, Huang CY, Lee CH, Kao KC, et al. Prolonged mechanical ventilation in a respiratory-care setting: a comparison of outcome between tracheostomized and translaryngeal intubated patients. Crit Care. 2010. 14:R26.

8. Robson V, Poynter J, Lawler PG, Baudouin SV. The need for a regional weaning centre, a one-year survey of intensive care weaning delay in the Northern Region of England. Anaesthesia. 2003. 58:161–165.

9. 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.

10. Cox CE, Carson SS, Govert JA, Chelluri L, Sanders GD. An economic evaluation of prolonged mechanical ventilation. Crit Care Med. 2007. 35:1918–1927.

11. Dematte D'Amico JE, Donnelly HK, Mutlu GM, Feinglass J, Jovanovic BD, Ndukwu IM. Risk assessment for inpatient survival in the long-term acute care setting after prolonged critical illness. Chest. 2003. 124:1039–1045.

12. Carson SS, Bach PB, Brzozowski L, Leff A. Outcomes after long-term acute care. An analysis of 133 mechanically ventilated patients. Am J Respir Crit Care Med. 1999. 159(5 Pt 1):1568–1573.

13. Lee K, Hong SB, Lim CM, Koh Y. Sequential organ failure assessment score and comorbidity: valuable prognostic indicators in chronically critically ill patients. Anaesth Intensive Care. 2008. 36:528–534.

14. MacIntyre NR, Epstein SK, Carson S, Scheinhorn D, Christopher K, Muldoon S, et al. Management of patients requiring prolonged mechanical ventilation: report of a NAMDRC consensus conference. Chest. 2005. 128:3937–3954.

15. Knaus WA, Draper EA, Wagner DP, Zimmerman JE. APACHE II: a severity of disease classification system. Crit Care Med. 1985. 13:818–829.

16. Vincent JL, Moreno R, Takala J, Willatts S, De Mendonça A, Bruining H, et al. The SOFA (Sepsis-related Organ Failure Assessment) score to describe organ dysfunction/failure. On behalf of the Working Group on Sepsis-Related Problems of the European Society of Intensive Care Medicine. Intensive Care Med. 1996. 22:707–710.

17. Miranda DR, de Rijk A, Schaufeli W. Simplified Therapeutic Intervention Scoring System: the TISS-28 items: results from a multicenter study. Crit Care Med. 1996. 24:64–73.

18. 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.

19. Nelson JE, Mercado AF, Camhi SL, Tandon N, Wallenstein S, August GI, et al. Communication about chronic critical illness. Arch Intern Med. 2007. 167:2509–2515.

20. Cox CE, Martinu T, Sathy SJ, Clay AS, Chia J, Gray AL, et al. Expectations and outcomes of prolonged mechanical ventilation. Crit Care Med. 2009. 37:2888–2894.

21. Song T, Kim K, Koh Y. Factors determining the establishment of DNR orders in oncologic patients at a university hospital in Korea. Korean J Med. 2008. 74:403–410.