Predictors of prolonged hospital stay in a Comprehensive Stroke Unit.

OBJECTIVE: to analyze the in-hospital complications of prolonged hospital stay in patients with ischemic stroke or transient ischemic attack, admitted to the stroke unit of a tertiary hospital.
METHOD: this is an evaluative correlational study. All first-ever ischemic stroke or transient ischemic attack patients admitted were retrospectively analyzed. During hospital stay, the predictors of long-term hospitalization considered were: 1) clinical complications (pneumonia, urinary tract infection, pressure damage and deep vein thrombosis), and 2) neurological complications (malignant ischemic stroke and symptomatic hemorrhagic transformation).
RESULTS: 353 patients were discharged in the study period. Mean age was 64.1±13.7 years old and 186 (52.6%) were men. The mean time of hospital stay was 13.7±14.3 days. Pneumonia (25.3±28.8 days, p<0.001), urinary tract infection (32.9±45.2 days, p<0.001) and malignant stroke (29.1±21.4 days, p<0.001) increased significantly the length of hospital stay compared to patients without any complications (11.2±7.1 days).
CONCLUSION: this study showed that three complications delayed hospital discharge in patients admitted in a stroke unit, two preventable ones: pneumonia and urinary tract infection. More intense measures to avoid them should be included in the performance indicators to reduce the length of hospital stay in stroke units.

Introduction

Stroke is one of the most common causes of mortality and disability with a high impact in the health of world population[1]. In Brazil, although the mortality rate has decreased in the last years, the incidence is still very high[2-3].

In patients with acute stroke, adequate evaluation and care support during hospitalization are mandatory. The reperfusion therapy, the investigation of the etiological mechanism, the secondary prevention therapy and early rehabilitation could significantly improve the outcome[4-5]. Otherwise, the occurrence of clinical and neurological complications during hospital stay could influence negatively the patient outcome, delaying discharge[6] and increasing hospital costs[7] and intra-hospital mortality rates[8].

In a recent study, 76.9% of patients in a rehabilitation center presented at least one complication related to stroke and 20% had three or more complications[9]. The most common are related to infection, cardiovascular and venous thromboembolism, increasing disability and mortality. The identification of these complication could be considered as triggers of opportunity to improve the procedures and the interventions related to stroke care[10].

One of the most significant measures introduced in the clinical practice to improve the outcome and to reduce costs and hospital stay was the stroke unit[11-12]: a specific ward where the quality measures can be monitored continually[13]. A previous study demonstrated the impact of those findings in two distinct comprehensive stroke units[14], showing the value of an organized specialized center, with the nurse team predominantly looking for a better care.

This study aimed to analyze the in-hospital complications that delay hospital discharge in patients with ischemic stroke or transient ischemic attacks (TIA) admitted to the stroke unit of a tertiary hospital, becoming a benchmark to future studies.

Method

This is an evaluative correlational study. Data from all first-ever ischemic stroke or TIA patients admitted to the Stroke Unit of Hospital de Clínicas (Federal University of Paraná), between October 2012 and September 2015 were retrospectively analyzed.

Inclusion criteria were: patients older than 17 years, with a diagnosis of the first ischemic stroke or TIA. Patients admitted to the stroke unit transferred to an intensive care for supportive management were included. Patients with hemorrhagic stroke or other diagnoses were excluded (seizure, hypoglycemia). The following variables were analyzed: gender, age, arterial hypertension, diabetes mellitus, dyslipidemia, tobacco use, atrial fibrillation, alcoholism, congestive heart failure and coronary arterial disease. During admission, the predictors of long-term stay considered were: 1) clinical complications (pneumonia, urinary tract infection, pressure damage and deep vein thrombosis), and 2) neurological complications (malignant ischemic stroke and symptomatic hemorrhagic transformation).

Analyses were performed using Statistical Package for the Social Sciences 20.0 software. Quantitative variables were described by mean and standard deviations, or median with minimum and maximum values. Categorical variables were presented as frequencies and percentages. For comparison of the quantitative variables, Student’s t test, Mann-Whitney or Kruskal-Wallis non-parametric tests were used. Categorical variables were analyzed using a chi-square test or Fisher’s exact test. Normality of data was determined by using the Kolmogorov-Smirnov test. The Spearman’s correlation coefficient was considered to analyze the correlation between two quantitative variables. Statistical significance was accepted for p-values<0.05.

The study was approved by the Institutional Ethics Committee, under Opinion number, 1.891.218.

Results

A total of 353 patients were discharged in the studied period: 324 (91.8%) with ischemic stroke and 29 (8.2%) patients with TIA. The mean time of hospital stay was 13.7±14.3 days, the mean age was 64.1±13.7 years old, and 186 (52.6%) were men. The median National Institute Health Stroke Scale (NIHSS) on admission was 7 (0 e 29). Table 1 presents the demographic and risk factors of the population. From all the study patients, 130 (36.8%) were submitted to thrombolysis and 15 (78.9%) to decompressive craniectomy secondary to malignant stroke.

Table 1

– Demographic and risk factors of patients hospitalized in stroke unit. Curitiba, PR, Brazil, 2017

Variable (n=353)*	n	%
Arterial hypertension	290	82.4
Diabetes mellitus	108	30.6
Hypercholesterolemia	203	57.5
Current smoking	94	26.6
Alcohol intake	35	9.9
Atrial fibrillation	57	16.1
Coronary artery disease	31	8.8
Cardiac heart failure	48	13.6

*It could be more than one risk factor per patient

In-hospital complications occurred in 95 (26.9%) patients. Table 2 demonstrates the length of hospital stay comparing patients with and without complications.

Table 2

– Length of hospital stay in patients with and without complications hospitalized in stroke unit. Curitiba, PR, Brazil, 2017

Complications (n=353)*	n	%	Length of hospital stay (mean±sd†)	p-value
None	258	73.1	11.2±7.1
Pneumonia	49	13.9	25.3±28.8	<0.001
Urinary tract infection	17	4.8	32.9±45.2	<0.001
Pressure damage	03	0.8	37.7±20.6	NA‡
Malignant ischemic stroke	19	5.8	29.1±21.4	<0.001
Symptomatic hemorrhagic transformation	13	4.0	14.1±9.7	0.638

*It could be more than one complication per patient; †sd = standard deviation; ‡NA = not available

Discussion

The analysis of the length of stay and the study of the performance indicators are important predictors to the management and to improve the hospital care. Length of stay in patients with stroke could be related to many variables, including severity of the stroke, age and comorbidities. In this study, the length of stay had more days if compared to previous studies[1,15-18], probably because it was done in a comprehensive stroke center, with acute care and rehabilitation process. In relation to age, older patients have higher risk to stroke complications[19]; this study presented similar data compared to previous studies[20].

This research project showed that two preventable complications—pneumonia and urinary tract infection—and one neurological complication significantly increase the length of hospital stay in a stroke unit after the first-ever ischemic stroke or TIA. Previous studies demonstrated that pneumonia and urinary tract infection were the most common clinical complications after an ischemic stroke, increasing morbidity and mortality[21-23]. The frequency of these complications in the study population was very similar to previous published studies; pneumonia between 10.6% and 21.2%[6,24-25], and urinary tract infection between 3.2% and 5.0%[6,24]. There is a reciprocal interaction between complications and hospital stay; the infection retards the discharge, and the length of stay increases the risk of infection[26]. In this study, both infections increased in more than two weeks the length of hospital stay.

There are some predictors to pneumonia in patients with stroke, the most common are the severity of the stroke, altered level of consciousness, bronchoaspiration and disability[27]. These will increase the length of stay and hospital costs[28-29]. The early dysphagia diagnosis and management, checking the level of consciousness, and prevention from pulmonary aspiration could reduce the frequency of this critical and preventable event.

Regarding urinary tract infection, recent studies suggest that the absence of urinary catheter had lower risk of infection[30], this could be related to the technical procedure and the long-term catheter[31]. Monitoring for urinary function, avoiding urinary retention, and prolonged bladder drainage could reduce urinary tract infection[32]. The management of care and preventable procedures could be considered such as aseptic technique and drainage position.

In addition to the clinical complications observed, malignant stroke also increased the length of hospital stay in the current population. Usually, malignant stroke patients need a more intensive supportive care, and specific cases could be submitted to decompressive craniectomy[33]. These patients usually need intensive care support, increasing the length of stay[34] and requiring more intense rehabilitation program for recovery[35]. Even though most of these reperfusion hemorrhage are asymptomatic, they can sometimes provoke neurologic decline and, when severe, can be fatal[33]. Based on this, the introduction of specific guidelines for the early diagnosis of malignant stroke and the measures to define the outcome in this group of patients should be included in stroke centers[34], reducing mortality and disability.

Some important limitations of this study are as follows: the data are from a single public teaching hospital in Southern Brazil. As a retrospective study, it is not possible to evaluate if preventive measures were implemented to the prevalent complications, but all patients were admitted to the stroke unit with a standardized management protocol[11]. The results of this research did not include all types of stroke, since patients with hemorrhagic stroke or cerebral venous thrombosis were excluded, not supporting data of those diseases. A last significant point is that patients could extend their stay in hospital to improve the rehabilitation process and to start the secondary prevention therapy.

Conclusion

This study evidenced that three complications delayed hospital discharge of patients with first-ever ischemic stroke or TIA admitted in a stroke unit, two preventable ones—pneumonia and urinary tract infection. More intense measures to avoid them should be included in the performance indicators to reduce the length of hospital stay in stroke units. These results could be considered as benchmark to future studies.