Dysfunction of alveolar macrophages after cardiac surgery and postoperative pneumonia? - an observational study

Table 1 Baseline characteristics of the analyzed patient groups

Characteristics	Group 1 without pneumonia (n = 30)	Group 2 with pneumonia (n = 3)	P
Age, years	67 (59, 72)	79 (78, 84)	0.006^a
Gender, m/f	22 (73%)/8 (27%)	2 (66%)/1 (33%)	0.88
Smoker, %	3 (10%)	0 (0%)	0.49
BMI, kg m^-2	27.5 (25.5, 29.7)	26.9 (22.5, 28.03)	0.45
LVEF, %	55 (50, 60)	55 (50, 66)	0.75
Arterial hypertension, n/y	2/31	0/3	0.88
COPD, n/y	31/2	3/0	0.88
Renal insufficiency, %	2 (6.7%)	1 (33%)	0.49
Diabetes mellitus, %	6 (20%)	1 (33%)	0.75
Duration of anesthesia, minutes	270 (234, 318)	360 (330, 360)	0.019^a
Duration of surgery, minutes	213 (173, 244)	275 (275, 320)	0.025^a
CPB-time, minutes	73 (54, 99)	125 (101, 142)	0.030 ^a
Cross clamp time, minutes	41 (32, 61)	58 (40, 97)	0.235
Total ventilation time, hours	13 (11.0, 15)	24 (22, 25)	0.015^a
Intraoperative blood transfusion, n/y	7 (23%)	3 (100%)	0.025^a
Postoperativewound infection, %	4 (13.3%)	0 (0%)	0.75
Onset of pneumonia, postoperative day	n/a	5 (4, 5)	0.10
Sepsis, %	0 (0%)	2 (67%)	0.06

Data in brackets are presented as median and IQR or absolute values. ^aStatistically significant (P <0.05) (Mann–Whitney U-test for independent patient groups). Patients were divided retrospectively into two groups: group 1 without postoperative pneumonia and group 2 comprising three patients who developed postoperative pneumonia. m/f, male/female; n/y, no/yes; COPD, chronic obstructive pulmonary disease; CPB, cardiopulmonary bypass; n/a, not applicable.