To investigate the predictive value of acute physiological and chronic health Ⅱ (APACHE Ⅱ) score combined with serum procalcitonin (PCT), D-dimer (D-D) and lactate clearance rate (LCR) for poor prognosis in patients with severe sepsis.

The clinical data of 92 patients with severe sepsis treated in Santai Hospital, Affiliated Hospital of North Sichuan Medical College, Mianyang City, Sichuan Province from May 2018 to March 2020 were analyzed, retrospectively, and were recorded as observation group, while 80 healthy volunteers in hospital were selected as control group. APACHE Ⅱ score, levels of serum PCT, D-D and 6 h LCR were compared between the two groups. Patients in observation group were followed up for 28 days, and were divided into good prognosis group (recovered or improved) and poor prognosis group (without improvement, aggravation or even death) according to the prognosis; APACHE Ⅱ score, levels of serum PCT, D-D and LCR were compared between the two groups. The correlation between APACHE Ⅱ score, levels of serum PCT, D-D, LCR and poor prognosis were analyzed by Cox regression analysis. The correlation between serum PCT, D-D and LCR and APACHE Ⅱ score were analyzed by Pearson correlation analysis method. The predictive value of APACHE Ⅱ score combined with serum PCT, D-D and LCR for poor prognosis in patients with severe sepsis were evaluated by receiver operating characteristic curve (ROC), and area under curve (AUC) were compared by Medcalc software.

APACHE Ⅱ score [(18.78 ± 1.03) vs. (3.38 ± 0.57)], levels of serum PCT [(7.01 ± 1.35) μg/L vs. (0.24 ± 0.04) μg/L)], D-D [(1.73 ± 0.09) mg/L vs. (0.26 ± 0.05) mg/L)] of patients in observation group were significantly higher than those of control group (t = 118.814, 44.820, 129.689; all P < 0.001) , while serum LCR level of observation group was significantly lower than that of control group [(40.62 ± 6.92)% vs. (65.92 ± 7.80)%] (t = 22.541, P < 0.001), with significant difference. The incidence rate of poor prognosis was 52.17% (48/92). APACHE Ⅱ score [24.99 (21.26, 27.15) vs. 18.14 (15.59, 19.26)], levels of serum PCT [15.59 (8.20, 17.99) μg/L vs. 7.84 (7.00, 9.14) μg/L], D-D [5.38 (4.03, 5.77) mg/L vs. 1.76 (1.66, 1.90) mg/L] of patients with poor prognosis were significantly higher than those with good prognosis (U = 11.019, 17.751, 54.995; all P < 0.001), while LCR level was lower than that of patients with good prognosis [29.70 (26.58, 38.49)% vs. 40.70 (36.07, 45.08)%] (U = 9.750, P < 0.001), with significant difference. APACHE Ⅱ score was positively correlated with serum PCT (r = 0.804, P < 0.001) and D-D (r = 0.743, P < 0.001), while negatively correlated with serum LCR (r =-0.758, P = 0.007). Urea nitrogen, creatinine, APACHE Ⅱ score, PCT, D-D were all independent risk factors for poor prognosis of severe sepsis (HR = 1.044, 1.027, 1.256, 1.036, 1.024, 0.60; P = 0.005, 0.002, 0.026, 0.003, 0.004). Serum calcium concentration and LCR were independent protective factors for poor prognosis of severe sepsis (HR = 0.430, 0.609; P < 0.001). The sensitivity and area under curve (AUC) of APACHE Ⅱscore combined with serum PCT, D-D and LCR in predicting the poor prognosis of severe sepsis were significantly higher than those of single index (sensitivity: χ² = 15.036, 17.778, 13.714, 16.390, all P < 0.001; AUC: Z = 2.909, 4.640, 4.242, 3.983; all P < 0.001), but the specificity were without significant differences between four indexes combined and single index (χ² = 1.908, 0.155, 0.000, 0.715; P = 0.167, 0.694, 1.000, 0.938).

APACHE Ⅱ score, levels of serum PCT, D-D are higher, and the level of serum LCR is lower in patients with severe sepsis, which are related to poor prognosis, and combination of those indexes could predict the poor prognosis of patients with severe sepsis.