Delta neutrophil index versus lactate clearance: Early markers for outcome prediction in septic shock patients

Available online 29 June 2012

Peer review under responsibility of Alexandria University Faculty of Medicine.

Figures & data

Table 1 Baseline clinical characteristics of patients by survival.

Variables	Survivors (n = 36)	Non-survivors (n = 17)	P
Age (yr)	58.6 ± 14.5	64.4 ± 12.4	0.106
Male	25 (69.4%)	13 (76.5%)
Female	11 (30.6%)	4 (23.5%)	0.225
Weight (kg)	79.6 ± 7.25	76.5 ± 6.98	0.336
Primary site of infection:
Lung	19 (52.8%)	11 (64.7%)	0.098
Intra-abdomen	8 (22.2%)	4 (23.5%)	0.699
Genitourinary	7 (19.4%)	2 (11.8%)	0.72
Others	2 (5.6%)	0 (0%)	0.366
Positive blood culture	17 (47.2%)	12 (70.6%)	0.034∗
Gram positive	6(16.7%)	4 (23.5%)	0.045∗
Gram negative	9 (25.0%)	6 (35.3%)	0.041∗
Fungus	2 (5.6%)	2 (11.8%)	0.075
None detected	19 (52.8%)	5 (29.4%)	0.011∗
APACHE II	19.9 ± 6.8	21.6 ± 6.8	0.285
GCS	9.28 ± 2.11	10.9 ± 3.25	0.22

Table 2 Comparisons between survivors and non-survivors as regards; SOFA scores and vital signs.

Variables	Survivors	Non-survivors	P
	(n 36)	(n17)
Temperature °C	36.8 ± 2.6	37.6 ± 1.8	0.822
Respiratory rate (breath/min)	28.4 ± 3.1	27.6 ± 2.9	0.789
Heart rate (beats/min)	114.5 ± 24.6	116.5 ± 20.5	0.698
MAP(mm Hg)	74.1 ± 22.1	79.6 ± 23.4	0.541
SOFA score	7.9 ± 4.2	11.7 ± 4.8	0.039^∗

Table 3 Hematologic and laboratory variables in relation to DNI and lactate-6h-clearance in patients with severe sepsis/septic shock.

Variable	Survivors	Non-survivors	P
	(n = 36)	(n = 17)
DNI%	5.2 ± 1.2	19.0 ± 3.22	0.0001^∗
WBC, per mm^3	17.9 ± 11.6	18.7 ± 7.5	0.452
Hematocrit, %	39.0 ± 6.8	36.1 ± 7.4	0.1558
Platelet, per mm^3	274,000 ± 109,000	190,000 ± 77,000	0.017^∗
Prothrombin time (s)	16.7 ± 3.6	20.1 ± 8.3	0.047^∗
Base deficit (mmol/L)	7.4 ± 8.1	8.6 ± 5.8	0.107
Ph	7.32 ± 0.19	7.30 ± 0.21	0.65
DIC	11(30.5%)	10(58.8%)	0.005^∗
D-dimer (ng/mL)	2657 ± 1049	4163 ± 2311	0.0025^∗
Lactate clearance %	36.49 ± 12.11	14.72 ± 7.11	0.001^∗
Initial lactate, mmol/L	6.28 ± 2.18	6.01 ± 1.66	0.127
6 h Lactate, mmol/L	3.36 ± 1.15	4.97 ± 2.01	0.018∗

Table 4 Correlation between DNI and DIC parameters.

DNI #	R	P
Platelet count	−0.4582	0.013^∗
D-dimer	0.339	0.028^∗
Prothrombin time (secs)	0.487	0.011^∗
DIC	0.399	0.0212^∗

R: Correlation coefficient.

Figure 1 Roc curve to determine the sensitivity and specificity of DNI, lactate and lactate-6h-clearance.

Table 5 Sensitivity and specificity of DNI, lactate and lactate-6h-clearance.

	Sensitivity	Specificity	PPV	NPV
DNI	95.0	90.0	92.0	95.0
Lactate-6h-clearance	92.5	85.0	90.0	88.0
Lactate	88.6	78.0	82.6	75.0

NPV: negative predictive value.

PPV: positive predictive value.