Prediction of in-hospital mortality in patients with exertional heatstroke: a 13-year retrospective study

Figures & data

Figure 1. Flowchart of all excluded and included patients.

Table 1. Baseline characteristics of patients with EHS in survivors and non-survivors group.

	Total (N = 210)	Survivors (N = 191)	Non-survivors (N = 19)	P-value
Age, years	30 (21–55)	29 (20–48)	32 (21–49)	.696
Gender				.604
Male, N (%)	200 (95.2%)	181 (94.8%)	19 (100%)
Female, N (%)	10 (4.8%)	10 (5.2%)	0 (0%)
Month distribution				.238
June, N (%)	59 (28.1%)	55 (28.8%)	4 (21.1%)
July, N (%)	59 (28.1%)	56 (29.3%)	3 (15.8%)
August, N (%)	36 (17.1%)	30 (15.7%)	6 (31.6%)
Other, N (%)	56 (26.7%)	50 (26.2%)	6 (31.6%)
Predisposing factors				.567
Upper respiratory tract infection, N (%)	9 (4.3%)	8 (4.2%)	1 (5.3%)
Acute enteritis, N (%)	4 (1.9%)	4 (2.1%)	0 (0%)
Insufficient sleep, N (%)	8 (3.8%)	7 (3.7%)	1 (5.3%)
Underlying disease, N (%)	38 (18.1%)	33 (17.3%)	5 (26.3%)	.350
T,°C	37.0 (36.6–38.0)	37.0 (36.5–37.8)	38.2 (37.0–39.8)	.001
HR, per minute	85 (74–106)	84 (73–102)	121 (103–135)	<.001
MAP, mmHg	87 ± 16	87 ± 15	83 ± 23	.466
RR, per minute	20 (20–22)	20 (20–22)	20 (20–30)	.392
MV, N (%)	38 (28.6%)	26 (21.5%)	12 (60%)	<.001
VD, N (%)	27 (17.3%)	16 (8.6%)	11 (68.8%)	<.001
WBC, ×10^9/L	11.51 (8.36–19.69)	11.50 (8.32–15.09)	10.32 (8.49–14.08)	.523
Neutrophil, ×10^9/L	9.15 (6.05–12.48)	9.21 (6.12–12.47)	8.59 (5.00–1.08)	.811
Monocytes, ×10^9/L	0.53 (0.30–0.78)	0.54 (0.33–0.79)	0.48 (0.24–0.76)	.166
Lymphocyte, ×10^9/L	1.30 (0.68–2.09)	1.40 (0.73–2.09)	0.40 (0.23–2.10)	.009
Hb, g/L	140 (126–156)	141 (126–158)	131 (85–146)	.005
PC, ×10^9/L	170 ± 90	179 ± 87	84 ± 71	<.001
APTT, s	33.5 (27.1–40.6)	33.3 (26.8–39.5)	40.1 (30.7–99.0)	.040
PT, s	14.8 (12.5–18.1)	14.6 (12.4–17.5)	20.7 (15.2–35.0)	.001
INR	1.20 (1.06–1.52)	1.16 (1.04–1.47)	1.76 (1.32–3.62)	<.001
D-dimer, μg/mL	0.98 (0.34–4.38)	0.81 (0.32–3.53)	10.02 (4.41–20.05)	<.001
Fib, g/L	2.50 (2.08–3.68)	2.52 (2.10–3.00)	1.80 (1.23–2.50)	<.001
Scr, μmol/L	131 (94–184)	129 (92–173)	184 (153–258)	.002
BG, mmol/L	6.2 (5.3–8.0)	6.2 (5.3–8.0)	6.0 (4.1–7.9)	.236
AST, U/L	62 (28–191)	51 (28–139)	260 (86–1715)	<.001
CK, U/L	631 (243–1705)	543 (237–1338)	1710 (607–6909)	.011
DIC, N (%)	37 (17.6%)	26 (13.6%)	11 (57.9%)	<.001
Rhabdomyolysis, N (%)	78 (37.1%)	66 (34.6%)	12 (63.2%)	.014
GCS score	15 (7–15)	15 (9–15)	6 (3–8)	<.001
ISTH score	2 (0–3)	2 (0–3)	5 (3–7)	<.001
SIRS score	1 (0–2)	1 (0–2)	2 (2–3)	.003
APACHE II score	9 (5–17)	8 (4–14)	20 (17–28)	<.001
SOFA score	3 (2–6)	3 (2–6)	9 (7–11)	<.001
LoICUS, days	4 (1–7)	3 (1–7)	8 (5–15)	.001
LoHS, days	8 (3–15)	7 (3–14)	11 (5–17)	.213

Data are presented as N (percentage), median (interquartile range) or mean ±standard deviation.

Abbreviations: T, temperature; HR, heart rate; MAP, mean artery pressure; RR, respiratory rate; MV, mechanical ventilation; VD, vasoactive drug. WBC, white blood cell; Hb, hemoglobin; PC, platelet count; APTT, activated partial thromboplastin time; PT, prothrombin time; INR, international normalized ratio; Fib, fibrinogen; Scr, serum creatinine; BG, blood glucose; AST, aspartate aminotransferase; CK, creatine kinase; DIC, disseminated intravascular coagulation; GCS, Glasgow coma scale; ISTH, International Society for Thrombosis and Haemostasis; SIRS, systemic inflammatory response syndrome; APACHE II, acute physiology and chronic health evaluation II; SOFA, sequential organ failure assessment. LoICUS, length of intensive care unit stay; LoHS, the length of hospital stay.

Table 2. Univariate logistic analysis of factors associated with in-hospital mortality in patients with EHS. T, temperature; HR, heart rate; Hb, hemoglobin; Scr, serum creatinine; AST, aspartate aminotransferase; GCS, Glasgow coma scale; DIC, disseminated intravascular coagulation; OR, odds ratio; CI confidence interval.

Variable	OR	95% CI	P-value
Age	1.008	0.977–1.040	0.615
T,°C	1.753	1.309–2.349	<.001
HR, per minute	1.035	1.019–1.051	<.001
Lymphocyte, ×10^9/L	0.747	0.476–1.172	.204
Hb, g/L	0.967	0.950–0.984	<.001
Scr, μmol/L	1.005	1.001–1.009	.019
AST, U/L	1.000	1.000–1.000	.072
GCS score	0.757	0.670–0.855	<.001
Rhabdomyolysis
No	1		1
Yes	3.247	1.220–8.640	.018
DIC
No	1		1
Yes	8.726	3.209–23.725	<.001

Table 3. Multivariate logistic analysis of factors associated with in-hospital mortality in patients with EHS.

Variable	β	OR	95% CI	P-value
T, °C	0.506	1.658	1.142–2.408	.008
GCS score	−0.167	0.847	0.736–0.974	.019
DIC
No		1		1
Yes	2.030	7.616	2.175–26.673	.001
Constant	−20.751	.000		.007

β is the regression coefficient, p-value < .005 means significant.

T, temperature; GCS, Glasgow coma scale; DIC, disseminated intravascular coagulation; OR, odds ratio; CI, confidence interval.

Figure 2. The ROC curve analyses of predictive model, T, DIC and GCS score. T, temperature; DIC, disseminated intravascular coagulation; GCS, Glasgow coma scale.

Table 4. The ROC curve analysis of predictive model, T, DIC, GCS, SOFA, APACHE II and SIRS score to predict in-hospital mortality.

	AUC	95% CI	P-value	Cutoff	SEN (%)	SPE (%)	YI
Predictive model	0.897	0.848–0.935	<0.0001	0.02842	100	66.49	0.6649
T	0.739	0.674–0.797	.0001	37.6	68.42	68.59	0.3701
DIC	0.721	0.656–0.781	.0002	1	57.89	86.39	0.4428
GCS	0.822	0.764–0.872	<.0001	8	84.21	75.92	0.6013
SOFA	0.924	0.880–0.956	<.0001	5	100	74.87	0.7487
APACHE II	0.838	0.781–0.885	<.0001	16	78.95	80.10	0.5905
SIRS	0.699	0.632–0.760	.0002	1	78.95	59.69	0.3863

T, temperature; DIC, disseminated intravascular coagulation; GCS, Glasgow coma scale; SOFA, sequential organ failure assessment; APACHE II, acute physiology and chronic health valuation II; SIRS, systemic inflammatory response syndrome. AUC, area under the curve; CI, confidence interval; SEN, sensitivity; SPE, specificity; YI, Youden Index.

Figure 3. The ROC curve analyses of predictive model, SOFA, APACHE II and SIRS score. SOFA, sequential organ failure assessment; APACHE II, acute physiology and chronic health evaluation II; SIRS, systemic inflammatory response syndrome.

Figure 4. The nomogram for prediction of in-hospital mortality in patients with EHS and was developed by GCS score, DIC and temperature in all cohort. GCS, Glasgow coma scale; DIC, disseminated intravascular coagulation.

Figure 5. The calibration curve of the nomogram for prediction of in-hospital mortality in patients with EHS. EHS, exertional heatstroke.