Is hypercapnea a predictor of better survival in the patients who underwent mechanical ventilation for chronic obstructive pulmonary disease (COPD)?
BACKGROUND
There are contradictory reports concerning hypercapnia as a predictor of a better outcome in COPD. This study examined the clinical implications of hypercapnea in COPD patients (M:F = 59:19) who required mechanical ventilation.


METHODS
The clinical parameters at the time of MICU admission, the total ventilation time, the APACHE II score and the pulmonary function testing were retrospectively analyzed between the survivors and nonsurvivors.


RESULTS
Univariate analysis showed that compared with the nonsurvivors, the survivors had lower AaDO2 values (59.8 +/- 53.5 vs. 105.0 +/- 73.3 mmHg, p=0.000), higher PaCO2 values (64.9 +/- 16.0 vs. 48.9 +/- 17.8 mmHg, p=0.000), lower APACHE II scores (19.0 +/- 3.8 vs. 24.1 +/- 5.1, p=0.002), the more frequent application of initial noninvasive positive pressure ventilation (44.0 vs. 14.3%, p=0.008), and a lower combined rate of septic shock (4.0 vs. 39.3%, p=0.000). Multivariate analysis revealed that a lower PaCO2 (OR: 0.94, p=0.008), the presence of septic shock (OR: 10.16, p=0.011), a higher APACHE II score (OR: 1.22, p=0.040) and a longer ventilation time (OR: 1.002, p=0.041) were the risk factors for mortality. A lower PaCO2 was also verified as the predictor. for mortality by multivariate analysis when excluding septic shock.


CONCLUSIONS
Hypercapnia at admission is thought to be an independent predictor of better survival for the COPD patients who require mechanical ventilation.
Park
Joo Hun
JH
Department of Pulmonary and Critical Care Medicine, Ajou University School of Medicine, Suwon, Korea.
Koh
Younsuck
Y
Lim
Chae-Man
CM
Hong
Sang-Bum
SB
Oh
Yeon Mok
YM
Shim
Tae Sun
TS
Lee
Sang Do
SD
Kim
Woo Sung
WS
Kim
Dong Soon
DS
Kim
Won Dong
WD
D018806:APACHE; D000368:Aged; D015415:Biomarkers; D005260:Female; D006801:Humans; D006935:Hypercapnia; D008297:Male; D015999:Multivariate Analysis; D010343:Patient Admission; D011379:Prognosis; D029424:Pulmonary Disease, Chronic Obstructive / Q000401:mortality* / Q000628:therapy; D012121:Respiration, Artificial / Q000379:methods; D012131:Respiratory Insufficiency; D012189:Retrospective Studies; D012307:Risk Factors; D016019:Survival Analysis; D016896:Treatment Outcome
D015415:Biomarkers