craniocerebral trauma - intensive care units - hemotherapy service - ventilator weaning
traumatismos craniocerebrais - unidades de terapia intensiva - serviço de hemoterapia
- desmame do respirador
The traumatic brain injury (TBI) is one of the main problems of world public health
because it generates strong economic impact and high mortality. In the United States,
an average of 2.5 million people suffers TBI annually, which generates estimated spending
by more than $ 76 billion/year[1]. About 10% of patients die before any medical care, other 4% die in hospital, and
another 10% evolve with permanent neurological sequelae[2].
In an attempt to reduce the mortality rates by TBI, huge efforts have been done in
order to determine treatment protocols for these patients. The identification of epidemiological
characteristics can guide intervention at primary prevention, as well as the determination
of predictor factors of death can guide the medical conduct during the treatment.
These interventions can promote cost reduction and promote reduction of secondary
lesions that generate functional disability[1],[3].
Based on this, the objective of this work is to identify the factors associated with
the intra-hospital mortality in patients with TBI admitted to intensive care unit
(ICU).
METHODS
This is an observational study, retrospective, held at the Intensive Care Unit (ICU)
of the Teresina Urgency Hospital Dr. Zenon Rocha (HUT) in Teresina, Piauí, Brazil.
It was included the medical records of patients with TBI admitted consecutively during
a period of one year in an Intensive Care Unit (ICU), in which was possible to collect
data from admission to the primary endpoint: intra-hospital death or hospital discharge.
Patients with non-traumatic lesion were excluded, as the transferred patients, who
the primary endpoint could not be known.
The following variables were collected: (A) Epidemiological variables: age, sex, causal
factor of TBI, tomographic findings during ICU admission, systemic trauma associated
with TBI. (B) Clinical variables associated with hospitalization and management in
intensive care unit: Severity of TBI, initial procedure after admission to the urgency,
use of mechanical ventilation in the ICU, use of vasoactive drugs, hemotransfusion,
hemodialysis, and nosocomial infection. These variables were considered independent
variables. The intra-hospital death was considered as the dependent variable.
The data collected were organized in Microsoft Excel 2010 Program database and, subsequently,
exported to the software IBM SPSS version 20.0 for Windows, in which were analyzed. To test the normality of the study variables, it was used
the statistical test of Kolmogorov-Smirnov. Continuous variables are presented as
mean ± standard deviation (SD), and categorical in proportions. Univariate analysis
was performed for evaluation association between the dependent variable and the other
variables, It is used the chi-square test (X2) for categorical variables and the Student
t test and Mann-Whitey test for continuous variables parametric and nonparametric,
respectively. Multivariate analyses by logistic regression were used to evaluate the
influence of the variables independently of the intra-hospital deaths. The level of
statistical significance was determined by p < 0.05.
This project was approved by the Ethics Committee in Research of the Teresina Urgency
Hospital Dr. Zenon Rocha (HUT) with protocol number 36/12.
RESULTS
It was selected 87 patients, with minimum aged of 15 years and maximum of 82 years,
and average of 28.93 ± 12.72 years. From this total, 77 (88.5%) were men and 10 (11.5%)
women. The most prevalent age group was 21-30 years, representing 39.1% of the sample.
With regard to surgery before ICU admission, 53 patients (60.9%) were operated, and
34 (39.1%) received clinical treatment. About the severity of trauma, 64 patients
(73.6%) received a diagnosis of severe TBI, with Glasgow coma scale (GCS) <= 8; 16
(18.4%) of TBI moderate; and 7 (8%) of mild TBI ([Table 1]).
Table 1
Clinical and epidemiological characteristics of the studied sample (n = 87). Values
presented in absolute frequency (n) and relative frequency (%).
|
Variables
|
n
|
%
|
|
Age
|
|
0–20 years
|
25
|
28.7
|
|
21–30 years
|
34
|
39.1
|
|
31–40 years
|
15
|
17.2
|
|
41–50 years
|
7
|
8
|
|
51–60 years
|
2
|
2.3
|
|
> 60 years
|
4
|
4.6
|
|
Gender
|
|
Male
|
77
|
88.5
|
|
Female
|
10
|
11.5
|
|
Comorbidities
|
|
Yes
|
5
|
5.7
|
|
No
|
82
|
94.3
|
|
Severity of TBI
|
|
Mild
|
7
|
8
|
|
Moderate
|
16
|
18.4
|
|
Severe
|
64
|
73.6
|
|
Treatment
|
|
Clinical
|
34
|
39.1
|
|
Surgical
|
53
|
60.9
|
|
Time of stay in ICU (days)
|
20.23 ± 18.02
|
-
|
|
Total time of hospitalization (days)
|
40.36 ± 26.86
|
-
|
TBI: Traumatic brain injury. Source: Intensive Care Unit (ICU) of the Emergency Hospital
of Teresina, Piauí, Brazil.
Seventeen patients (19.5%) reported alcohol consumption prior to the event. The others
70 (80.5%) had not consumed alcoholic beverage or did not report the use of it. During
the entire period of intensive care, 85 patients (97.7%) needed respiratory support.
The use of vasoactive drugs occurred in 53 patients (60.9%). Thirty six patients (41.4%)
received blood transfusion and 66 of the hospitalized (75.9%) acquired any nosocomial
infection. One patient (1.1%) progressed with acute renal failure, requiring hemodialysis.
Regarding to the intrahospital mortality, it was observed 22 deaths (25.3%); from
these deaths, 18 (81.8%) were patients with severe TBI ([Table 2]).
Table 2
Univariate analysis of categorical variables associated with intra-hospital death
in patients victims of TBI admitted to the ICU of the Emergency Hospital of Teresina.
|
Variables
|
Death n (%)
|
Hospital discharge n (%)
|
Total n (%)
|
p
|
|
Gender
|
|
Male
|
19 (31.1)
|
42 (68.9)
|
61(92.4)
|
0.202
|
|
Female
|
3 (60)
|
2 (40)
|
5 (7.6 )
|
|
|
Previous comorbidities
|
|
Yes
|
1 (33.3)
|
2 (66.7)
|
3 (4.5)
|
0.701
|
|
No
|
21 (33.3)
|
42 (66.7)
|
63 (95.5)
|
|
|
Alcohol use
|
|
Yes
|
(7.1)
|
13 (92.9)
|
14 (21.2)
|
0.016 *
|
|
No
|
21 (40.4)
|
31 (59.6)
|
52 (78.8)
|
|
|
Severe TBI
|
|
Yes
|
18 (38.3)
|
29 (61.7)
|
47 (71.2)
|
|
|
No
|
4 (21.1)
|
15 (78.9)
|
19 (28.8)
|
0.178
|
|
DAI at CT
|
|
Yes
|
(16.7)
|
5 (83.3)
|
6 (9.1)
|
0.655
|
|
No
|
21 (35)
|
39 (65)
|
60 (90.9)
|
|
|
Systemic trauma
|
|
Yes
|
15 (37.5)
|
25 (64.5)
|
40 (60.6)
|
0.373
|
|
No
|
7 (26.9)
|
19 (73.1)
|
26 (39.4)
|
|
|
Mechanical ventilation
|
|
Yes
|
22 (33.8)
|
43(66.2)
|
65 (98.5)
|
0.667
|
|
No
|
-
|
1 (100)
|
1 (1.5)
|
|
|
Use of vasoactive drugs
|
|
Yes
|
18 (39.1)
|
28 (60.9)
|
46 (69.7)
|
0.130
|
|
No
|
4 (20)
|
16 (80)
|
20 (30.3)
|
|
|
Hemotransfusion
|
|
Yes
|
6 (20)
|
24 (80)
|
30 (45.5)
|
0.036*
|
|
No
|
16 (44.4)
|
20 (55.6)
|
36 (54.5)
|
|
|
Nosocomial infection
|
|
Yes
|
15 (31.25)
|
33 (68.75)
|
48 (72.7)
|
0.558
|
|
No
|
7 (38.9)
|
11 (61.1)
|
18 (27.3)
|
|
|
Multidrug-resistant germ
|
|
Yes
|
6 (27.3)
|
16 (72.7)
|
22 (33.3)
|
0.915
|
|
No
|
10 (28.6)
|
25 (71.4)
|
35 (66.7)
|
|
|
ARF
|
|
Yes
|
1 (100)
|
-
|
1 (1.5)
|
0.333
|
|
No
|
21 (32.3)
|
44 (67.7)
|
65 (98.5)
|
|
|
Hemodialysis
|
|
Yes
|
1 (100)
|
-
|
1 (1.5)
|
0.333
|
|
No
|
21 (32.3)
|
44 (67.7)
|
65 (98.5)
|
|
Source: Intensive Care Unit (ICU) of the Emergency Hospital of Teresina, Piauí, Brazil.
TBI: traumatic brain injury; DAI: diffuse axonal injury; CT: computed tomography;
ARF: acute renal failure; *statistical significance.
Among the variables studied, in the univariate analysis, it was seen in association
with intra-hospital deaths the use of alcohol (p = 0.016), the blood transfusion (p
= 0.036) ([Table 2]), and the duration of mechanical ventilation (p = 0.002) ([Table 3]).
Table 3
Univariate analysis of the continuous variables associated with intra-hospital death
in patients victims of TBI admitted to the ICU of the Emergency Hospital of Teresina.
|
Independent variable
|
Death yes
|
Death no
|
p-value
|
|
Age
|
27.90 ± 14.48
|
30.72 ± 12.83
|
0.267
|
|
Time of trauma to admission to ICU
|
44.00 ± 49.79
|
43.32 ± 40.09
|
0.982
|
|
Trauma time CT
|
3.90 ± 5.52
|
2.98 ± 3.66
|
0.734
|
|
MV time
|
22.19 ± 20.04
|
13.18 ± 17.52
|
0.002*
|
|
Total hospital stay
|
32.07 ± 28.77
|
44.69 ± 28.52
|
0.065
|
Source: Intensive Care Unit of the Emergency Hospital of Teresina, Piauí, Brazil.
CT: computed tomography; ICU: intensive care unit; MV: mechanical ventilation; *statistical
significance.
In multivariate analyses by logistic regression, blood transfusion (p = 0.021) and
duration of mechanical ventilation (p = 0.01) remained as independent predictors of
mortality.
The most common cause of TBI was motorcycle accident in 66 cases (75.9%), followed
by automobile accident in eight cases (9.2%) and running over in five cases (5.7%),
([Table 4]). In relation to the tomographic findings in ICU admission, 19 cases (21.8%) of
extradural hematoma, 10 (11.5%) subdural hematoma, and nine (10.3%) diffuse axonal
injury (DAI), while 31% of patients had combination of two or more lesions ([Table 5]).
Table 4
Distribution of causes of traumatic brain injury (TBI) treated at the Emergency Hospital
of Teresina.
|
Trauma mechanism
|
n
|
%
|
|
Automobile accident
|
8
|
9.2
|
|
Motorcycle accident
|
66
|
75.9
|
|
Running over
|
5
|
5.7
|
|
Firearm projectile
|
0
|
0
|
|
Beating
|
3
|
3.4
|
|
Fall
|
1
|
1.1
|
|
Fall of own height
|
2
|
2.3
|
|
Others
|
2
|
2.3
|
Source: Intensive Care Unit of the Emergency Hospital of Teresina, Piauí, Brazil.
Table 5
Distribution of the main tomographic findings in patients victims of traumatic brain
injury (TBI) treated at the Emergency Hospital in Teresina (n = 87).
|
Changes
|
n
|
%
|
|
Brain injury
|
8
|
9.2
|
|
Extradural haemorrhage
|
19
|
21.8
|
|
Subarachnoid hemorrhage
|
4
|
4.6
|
|
Subdural hematoma
|
10
|
11.5
|
|
Intraparenchymal hemorrhage
|
4
|
4.6
|
|
Diffuse axonal injury
|
9
|
10.3
|
|
Multiple injuries
|
27
|
31
|
|
Others
|
6
|
6.9
|
Source: Intensive Care Unit of the Emergency Hospital of Teresina, Piauí, Brazil.
Regarding the presence of systemic trauma associated with TBI, 24 patients (27.6%)
had chest trauma; 11 (12.6%) musculoskeletal trauma; and 35 (40.2%) showed no associated
trauma.
DISCUSSION
The TBI is the main cause of mortality as result of trauma in all age groups[3]. In 2010, about 2.5 million people suffered some form of TBI, which represented
an estimated expenditure of 76.5 billion dollars for the US government[1]. In Brazil, every year, a half million people require hospitalization as a result
of head trauma. In the city of Teresina, capital of the state Piauí, with an estimated
population of 814,230 inhabitants, and reference to approximately 2 million people
in the middle North of Brazil, this was the first study related to the topic.
In the studied sample, there was a predominance of young adult males, which is corroborated
by other series described[4],[5],[6],[7],[8]. There was a higher prevalence of severe TBI, due to the research scenario: the
intensive care unit. Due to higher lethality observed in patients with severe TBI,
it is justified to conduct studies that seek death predictor variables in intensive
care environment.
It was observed that motorcycle accidents were the leading cause of TBI, but there
was disagreement with other researchers about the same theme. According to a series
of Spain, automobile accidents represented 55% of the causes of TBI from 2005 to 2012.
Of these, 22.5% were with cars, 17.1% with pedestrians, 12.3% with motorcycles, and
3.6% with bicycles[9]. In similar studies conducted in Brazil, the leading cause of TBI was collision
between vehicles, followed by running over[10],[11]. In another study conducted in Bahia, the highest prevalence was fall from height,
followed by running over[8].
Regarding the tomographic findings for ICU admission, it was predominated the extradural
hematoma (EDH), followed by acute subdural hematoma (SDH). A study conducted in Europe,
published in 2014 correlated tomographic findings in the initial hospital admission
to the causal factor of TBI. It was observed that victims of traffic accidents presented
more intracerebral hemorrhages, followed by traumatic subarachnoid hemorrhage, cerebral
contusions, SDH, contusion and subdural hematoma, and less commonly, EDH[9].
Gender did not constitute variable associated with mortality (p = 0.202), which is
consistent with literature data[12],[13]. This means that despite more men have been victims of TBI, the males do not progress
to death independently.
However, it should be mentioned that the ratio M / F present in the study is high
(7.7: 1). In other studies that also observed this high ratio, the indexes appear
as 3.47: 1[12], and 4.8:1[8].
In univariate analysis, there was no significant association (p = 0.178) between the
scores equal to or less than 8 on the Glasgow coma scale (GCS) and lethality. A study
of 2014 found that GCS<=8 is more associated with rapid neurological deterioration,
and that these patients progressed more rapidly to death, especially because of complications
such as hypovolemic shock and hypoxia[9].
There was no correlation between the presence of systemic lesions associated with
TBI and lethality resulting from TBI in this casuistic (p = 0.373), as also demonstrated
by other studies[14],[15],[16].
The need for mechanical ventilation during ICU stay did not correlate with intra-hospital
mortality in univariate analysis (p = 0.667). Ventilatory support in the acute phase
of TBI is critical to prevent secondary lung injury as comorbidity, and it can promote
the stabilization of parameters of cerebral perfusion and adequacy of brain hemodynamics[17]. However, it should be mentioned that the mechanical ventilation time was an independent
predictor for intra-hospital mortality after multivariate analysis (p = 0.002).
These findings are in accordance with Gumus et. al.[17], that evaluated 830 patients in the postoperative period of cardiovascular surgery.
It was observed that in the group in which there was need for mechanical ventilation
for a prolonged period (> 24 hours), there was a higher intra-hospital mortality (p
= 0.001). The rate of neurological complications in patients with prolonged mechanical
ventilation (PMV) was 34.8%, while in the group without PMV was 5.4% (p = 0.001).
The rate of nosocomial infection in patients with PMV was 34.8%, while in the remaining
was 7.5%[17].
It was found a high proportion of patients admitted to the ICU who acquired nosocomial
infection (75.9%). However, there was no correlation between this variable and mortality
(p = 0.558). These findings are discordant with the study of Lia et. al., that associated
the diagnosis of nosocomial infection with high rates of clinical complications and
high mortality rate in patients admitted to intensive care unit for neurological and
no neurological causes[18].
In univariate analysis there was a correlation between reported use of alcohol and
intra-hospital mortality (p = 0.016). However, the use of alcohol was not an independent
variable predictor of mortality after multivariate analysis. Pandit et. al.[20], pointed that intoxication with ethanol in patients victims of severe TBI is not
directly related to mortality. However, there is a higher frequency of hospital complications
in the group of patients that made use of alcohol[19]. One possible explanation would be the fact of prior exposure to ethanol intensifies
neuroinflammatory response after TBI[20].
Another variable considered as a predictor of mortality in an independent way after
multivariate analysis was the realization of hemotransfusions (p = 0.036). Blood transfusion
has undesirable effects such as aggravation of acute inflammatory response, which
contributes to the increased incidence of multiple organ failure[21],[22], [3]. Duane et al.[24], showed that, although most patients victims of TBI alone do not require blood transfusion,
those who need it have higher mortality rates, and these patients are more likely
to undergo some surgical intervention. In addition, the most seriously injured patients
require more frequently blood transfusion, which leads to maintenance of systemic
inflammatory response[25]. In this study, the criteria used for hemotransfusions were presence of inadequate
tissue oxygenation signals, such as angina, electrocardiographic changes, hemodynamic
instability, cardiac decompensation and altered state of consciousness. In the absence
of clinical symptoms, blood transfusion was performed in patients whose hemoglobin
concentration was below 7 g/dL.
In conclusion, the predictive factors of intra-hospital mortality in patients with
TBI under intensive care were: mechanical ventilation time and hemotransfusions.
