Factors influencing outcomes after cardiopulmonary resuscitation in emergency department

doi:10.5847/wjem.j.issn.1920-8642.2013.03.005

Abstract

Abstract:

BACKGROUND: The outcome of cardiopulmonary resuscitation (CPR) may depend on a variety of factors related to patient status or resuscitation management. To evaluate the factors influencing the outcome of CPR after cardiac arrest (CA) will be conducive to improve the effectiveness of resuscitation. Therefore, a study was designed to assess these factors in the emergency department (ED) of a city hospital.
METHODS: A CPR registry conforming to the Utstein-style template was conducted in the ED of the First Affiliated Hospital of Wenzhou Medical College from January 2005 to December 2011. The outcomes of CPR were compared in various factors groups. The primary outcomes were rated to return of spontaneous circulation (ROSC), 24-hour survival, survival to discharge and discharge with favorable neurological outcomes. Univariate analysis and multivariable logistic regression analysis were performed to evaluate factors associated with survival.
RESULTS: A total of 725 patients were analyzed in the study. Of these patients, 187 (25.8%) had ROSC, 100 (13.8%) survived for 24 hours, 48 (6.6%) survived to discharge, and 23 (3.2%) survived to discharge with favorable neurologic outcomes. A logistic regression analysis demonstrated that the independent predictors of ROSC included traumatic etiology, first monitored rhythms, CPR duration, and total adrenaline dose. The independent predictors of 24-hour survival included traumatic etiology, cardiac etiology, first monitored rhythm and CPR duration. Previous status, cardiac etiology, first monitored rhythms and CPR duration were included in independent predictors of survival to discharge and neurologically favorable survival to discharge.
CONCLUSIONS: Shockable rhythms, CPR duration ≤15 minutes and total adrenaline dose ≤5 mg were favorable predictors of ROSC, whereas traumatic etiology was unfavorable. Cardiac etiology, shockable rhythms and CPR duration ≤15 minutes were favorable predictors of 24-hour survival, whereas traumatic etiology was unfavorable. Cardiac etiology, shockable rhythms, CPR duration ≤15 minutes were favorable predictors of survival to discharge and neurologically favorable survival to discharge, but previous terminal illness or multiple organ failure (MOF) was unfavorable.

Key words: Cardiac arrest, Cardiopulmonary resuscitation, Utstein-style, Logistical regression analysis, Outcome

Ji-ke Xue, Qiao-yun Leng, Yu-zhi Gao, Shou-quan Chen, Zhang-ping Li, Hui-ping Li, Wei-jia Huang, Jun-yan Cheng, Jie Zhang, Ai-wen He. Factors influencing outcomes after cardiopulmonary resuscitation in emergency department[J]. World Journal of Emergency Medicine, 2013, 4(3): 183-189.

Figures/Tables 3

Table 1

Outcomes of the patients in different factor groups after CPR

Variables		n (%)	ROSC			24-hour survival			Survival to discharge			Neurologically favorable survival to discharge
Variables		n (%)	n (%)	χ²	P	n (%)	χ²	P	n (%)	χ²	P	n (%)	χ²	P
Sex	Male	519 (71.6)	126 (24.3)	2.192	0.139	70 (13.5)	0.143	0.705	38 (7.3)	1.452	0.228	21 (4.0)	3.595	0.058
	Female	206 (28.4)	61 (29.6)			30 (14.6)			10 (4.9)			2 (1.0)
Age	<60y	526 (72.6)	106 (20.2)	31.859	0.000	49 (9.3)	32.310	0.000	27 (5.1)	6.860	0.009	13 (2.5)	3.065	0.080
	≥60y	199 (27.4)	81 (40.7)			51 (25.6)			21 (10.6)			10 (5.0)
Location of CA	OHCA	292 (40.3)	61 (20.9)	6.140	0.013	38 (13.0)	0.250	0.617	16 (5.5)	1.030	0.310	4 (1.4)	4.236	0.040
	IHCA	433 (59.7)	126 (29.1)			62 (14.3)			32 (7.4)			19 (4.4)
Time of collapse	6 am-12 pm	579 (79.9)	165 (28.5)	10.986	0.001	87 (15.0)	3.675	0.055	44 (7.6)	4.454	0.035	20 (3.5)	0.358	0.055
	0 am-6 am	146 (20.1)	22 (15.1)			13 (8.9)			4 (2.7)			3 (2.1)
Witnessed	By medical staff	440 (62.5)	129 (29.3)	8.655	0.013	65 (14.8)	1.085	0.581	33 (7.5)	4.079	0.130	20 (4.5)	8.445	0.015
	By bystander	264 (37.5)	56 (21.2)			33 (12.5)			15 (5.7)			3 (1.1)
	Not witnessed	21 (2.9)	2 (9.5)			2 (9.5)			0 (0.0)			0 (0.0)
Previous status	Terminal illness/MOF	278 (38.3)	38 (13.7)	34.628	0.000	22 (7.9)	13.108	0.000	2 (0.7)	25.399	0.000	1 (0.4)	10.175	0.001
	Non-terminal illness/MOF	447 (61.7)	149 (33.3)			78 (17.4)			46 (10.3)			22 (4.9)
Cause of CA	Traumatic etiology	283 (39.0)	29 (10.2)	58.611	0.000	6 (2.1)	53.194	0.000	0 (0.0)	32.912	0.000	0 (0.0)	11.211	0.000
	Non-traumatic etiology	442 (61.0)	158 (35.7)			94 (21.3)			48 (10.9)			23 (5.2)
Cause of CA	Cardiac etiology	126 (17.4)	58 (46.0)	32.636	0.000	45 (35.7)	61.632	0.000	27 (21.4)	54.090	0.000	18 (4.3)	61.317	0.000
	Non-cardiac etiology	599 (82.6)	129 (21.5)			55 (9.2)			21 (3.5)			5 (0.8)
First monitored rhythm	Shockable	106 (14.6)	52 (49.1)	35.10	0.000	43 (40.6)	74.84	0.000	31 (29.2)	102.8	0.000	18 (17.0)	77.067	0.000
	Non-shockable	619 (85.4)	135 (21.8)			57 (9.2)			17 (2.7)			5 (0.8)
Response time	≤5 min	460 (63.4)	140 (30.4)	14.166	0.000	75 (16.3)	6.670	0.010	42 (9.1)	12.822	0.000	21 (4.6)	6.756	0.009
	>5 min	265 (36.6)	47 (17.7)			25 (9.4)			6 (2.3)			2 (0.8)
CPR duration	≤15 min	89 (12.3)	87 (97.8)	274.47	0.000	59 (66.3)	235.16	0.000	32 (36.0)	141.21	0.000	18 (20.2)	96.039	0.000
	>15 min	636 (87.7)	100 (15.7)			41 (6.4)			16 (2.5)			5 (0.8)
Total adrenaline dose	≤5 mg	259 (35.7)	105 (40.5)	45.786	0.000	63 (24.3)	37.584	0.000	32 (12.4)	21.433	0.000	18 (6.9)	18.717	0.000
	>5 mg	466 (64.3)	82 (17.6)			37 (7.9)			16 (3.4)			5 (1.1)

Table 1

Table 2

Univariate logistic regression analysis on factors related to outcomes after CPR

Factors	CPR outcomes	β	S.E.	Wald	P	OR	95.0% CI forOR
Age	ROSC	1.001	0.181	30.677	0.000	2.720	1.909-3.875
	24-hour survival	1.210	0.221	29.975	0.000	3.355	2.175-5.174
	Survival to discharge	0.780	0.304	6.585	0.010	2.180	1.202-3.955
	Neurologically favourableoutcome	0.736	0.429	2.943	0.086	2.088	0.900-4.842
Location of CA	ROSC	0.441	0.179	6.093	0.014	1.554	1.095-2.206
	24-hour survival	0.111	0.222	0.250	0.617	1.117	0.724-1.724
	Survival to discharge	0.320	0.316	1.023	0.312	1.377	0.741-2.557
	Neurologically favourable outcome	1.195	0.555	4.630	0.031	3.304	1.112-9.815
Time of collapse	ROSC	-0.809	0.249	10.565	0.001	0.445	0.273-0.725
	24-hour survival	-0.593	0.313	3.587	0.058	0.553	0.299-1.021
	Survival to discharge	-1.096	0.530	4.271	0.039	0.334	0.118-0.945
	Nerurologically favourable outcome	-0.534	0.626	0.727	0.394	0.586	0.172-2.001
Witnessed	ROSC	-0.485	0.181	7.198	0.007	0.616	0.432-0.878
	24-hour survival	-0.214	0.225	0.901	0.342	0.808	0.520-1.255
	Survival to discharge	-0.410	0.320	1.647	0.199	0.663	0.354-1.242
	Neurologically favourable outcome	-1.499	0.624	5.771	0.016	0.223	0.066-0.759
Previous status	ROSC	-1.150	0.201	32.209	0.000	0.317	0.213-0.470
	24-hour survival	-0.900	0.255	12.484	0.000	0.407	0.247-0.670
	Survival to discharge	-2.762	0.727	14.451	0.000	0.063	0.015-0.262
	Neurologically favourable outcome	-2.663	1.025	6.745	0.009	0.070	0.009-0.520
Traumatic etiology	ROSC	-1.584	0.220	51.957	0.000	0.205	0.133-0.316
	24-hour survival	-2.523	0.429	34.645	0.000	0.080	0.035-0.186
	Survival to discharge	-3.537	1.013	12.181	0.000	0.029	0.004-0.212
	Neurologically favourable outcome	-2.740	1.024	7.152	0.007	0.065	0.009-0.481
Cardiac etiology	ROSC	1.134	0.205	30.737	0.000	3.108	2.081-4.640
	24-hour survival	1.704	0.234	53.181	0.000	5.495	3.476-8.686
	Survival to discharge	2.016	0.311	42.113	0.000	7.506	4.084-13.799
	Neurologically favourable outcome	2.986	0.516	33.450	0.000	19.800	7.199-54.461
First monitored rhythms	ROSC	1.239	0.217	32.512	0.000	3.452	2.255-5.286
	24-hour survival	1.907	0.242	62.184	0.000	6.730	4.190-10.809
	Survival to discharge	2.684	0.326	67.889	0.000	14.637	7.731-27.713
	Neurologically favourable outcome	3.224	0.518	38.695	0.000	25.118	9.097-69.358
Response time	ROSC	0.708	0.190	13.860	0.000	2.029	1.399-2.945
	24-hour survival	0.626	0.245	6.521	0.011	1.870	1.157-3.024
	Survival to discharge	1.467	0.444	10.943	0.001	4.337	1.818-10.346
	Neurologically favourable outcome	1.839	0.744	6.108	0.013	6.290	1.463-27.044
CPR duration	ROSC	5.452	0.723	58.789	0.000	233.160	56.476-962.596
	24-hour survival	3.351	0.276	147.098	0.000	28.541	16.606-49.053
	Survival to discharge	3.080	0.336	84.010	0.000	21.754	11.260-42.030
	Neurologically favourable outcome	3.466	0.521	44.281	0.000	31.994	11.529-88.792
Total adrenaline dose	ROSC	1.161	0.176	43.735	0.000	3.193	2.263-4.504
	24-hour survival	1.316	0.224	34.385	0.000	3.727	2.401-5.785
	Survival to discharge	1.377	0.317	18.902	0.000	3.965	2.131-7.377
	Neurologically favourable outcome	1.930	0.512	14.217	0.000	6.886	2.526-18.775

Table 2

Table 3

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CPR outcome	Factors	β	S.E.	Wald	P	OR	95.0% CIfor OR
ROSC	Traumatic	-1.278	0.269	22.568	0.000	0.279	0.164-0.472
	First monitored rhythm	0.754	0.287	6.903	0.009	2.125	1.211-3.729
	CPR duration	5.126	0.734	48.819	0.000	168.293	39.960-708.771
	Total adrenaline dose	0.486	0.231	4.45	0.035	1.626	1.035-2.556
24-hour survival	Traumatic	-1.702	0.467	13.253	0.000	0.182	0.073-0.456
	Cardiac	0.666	0.319	4.373	0.037	1.947	1.043-3.635
	First monitored thythms	1.380	0.326	17.983	0.000	3.977	2.101-7.527
	CPR duration	3.074	0.309	99.108	0.000	21.635	11.811-39.630
Survival to discharge	Terminal illness/MOF	-3.318	0.744	19.887	0.000	0.036	0.008-0.156
	Cardiac	1865	0.446	17.503	0.000	6.459	2.695-15.477
	First monitored rhythms	2.109	0.417	25.544	0.000	8.237	3.636-18.659
	CPR duration	2.587	0.404	41.030	0.000	13.291	6.022-29.333
Neurologically favorable survival to discharge	Terminal illness/MOF	-3.585	1.130	10.072	0.002	0.028	0.003-0.254
	Cardiac	2.638	0.625	17.799	0.000	13.987	4.106-47.642
	First monitored rhythm	2.209	0.626	12.467	0.000	9.104	2.672-31.022
	CPR duration	2.723	0.616	19.516	0.000	15.226	4.549-50.961

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