Effect of Changing Selected body Positions on Oxygen Saturation among Patients with Acute Stroke

Introduction

A stroke is a clinical syndrome characterized by rapidly developing clinical symptoms and/ or signs of focal, and at times global (applied to patients in a deep coma and those with subarachnoid hemorrhage), loss of cerebral function, with symptoms lasting more than 24 h or leading to death, with no apparent cause other than that of vascular origin’. (Benjamin et al., 2019). A stroke, also called a brain attack, is a brain injury caused by a sudden interruption in the blood supply of the brain. It occurs either when part of the brain does not receive the needed blood flow the blood supply to part of the brain is suddenly interrupted, or because a blood vessel in the brain ruptures and blood invades the surrounding areas. (Perrin et al., 2018)

The epidemiology of stroke is changing rapidly and the global stroke burden continues to increase worldwide, stroke incidence is astonishing, with about 17 million people having a stroke each year. (Richard, 2017). World Health Organization is rating about 85% of stroke deaths in low and middle-income countries. The major health problem in the Egyptian population is a stroke; furthermore, Stroke Deaths in Egypt reached 56,710 or 11.04% of total deaths and thus ranks 3^rd after heart disease &gastrointestinal with a crude prevalence rate of 963/ 100,000 inhabitants. The clinical characteristics of Egyptian stroke patients are generally similar to those in other world populations. (Abotaleb et al., 2018)

Post-stroke brain damage, which affects the central control of respiration, leads to various respiratory disorders. Stroke patients may experience a reduction of up to 50% in respiratory function when compared to age- and gender-matched norms. The reduction in respiratory function can lead to decreased endurance, dyspnea, and increased sedentary behavior, as well as an elevated risk of stroke. The reduction in respiratory function may also cause aspiration, leading to pneumonia due to an inability to protect the airways and clear the airway by coughing, and acute pulmonary embolism due to prolonged mobilization. (Ptaszkowska et al., 2019)

Hypoxemiais observed in many patients with injury to the central nervous system. Physiologic and scientific literature to date supports the clinical efficacy of two noninvasive interventions, namely positioning and mobilization, which have both direct and profound effects on multiple steps of the oxygen transport pathway, which is reflected by the oxygen saturation (SpO2) level in blood. The literature supports the benefits of frequent body position changes, particularly for a patient who is relatively immobile, unalert, severely debilitated, obtunded, breathing at low lung volumes, obese, aged or very young, or has lost the sigh mechanism. Appropriate positioning of critically ill patients can significantly improve gas exchange. (Mehta et al., 2017)

Patient positioning is an independent nursing intervention and, although it is important in patients with cardiovascular, cardiopulmonary dysfunction, and oxygenation problems, there is insufficient evidence to suggest a particular position. The correct positioning of patients can affect the blood oxygen saturation level by increasing lung volume, reducing the heart rate, helping mucociliary clearance, and improving ventilation/perfusion (V/Q) matching. Optimal oxygenation depends on the V/Q matching. (Alan et al., 2019)

The stroke care nurse has a very important role in the care and guidance of the stroke patient. A particular body position, the time a body remains in a particular position, or changes in body position. The nurse caring for stroke patients involves multitasking such as mobilization, positioning, feeding, and early multidisciplinary rehabilitation. During the acute phase, nurses monitor the occurrence of i.e. lung inflammation, bedsores, urinary tract infections, thrombosis, delirium, depression, the degree of consciousness of the patient, injury of the affected side caused by neglect, inadequate posture, inadequate food or fluid intake. The SCN applies preventive interventions on the stroke care unit according to the hospital protocols to decrease the risk of those complications. (Buijck et al., 2018)

Significance of the Study:

Stroke is a common cause of morbidity and mortality worldwide. According to the World Health Organization, around 15 million people, worldwide, suffer from stroke each year. Four out of five strokes occur in low- and middle-income countries. Egypt is a developing country with a large population, the total lifetime prevalence of stroke in population aged 20 years and more in Upper Egypt (desert area) was 8.5/1,000. It lies within the range that is recorded in developing countries^. (Abd-Allah et al., 2018)

Mild hypoxia is common in stroke patients and may have significant adverse effects on the ischemic brain after stroke. Hypoxemia in the first few hours after hospital admission is associated with an increased risk of death (Roffe et al., 2014) Positioning in the early stages of acute stroke is carried out as a part of respiratory care for optimal oxygen saturation (Williams et al., 2020) So, from previously mentioned our study will be carried out to investigate the effect of changing selected body positions on oxygen saturation among patients with acute stroke.

Aimed of the study:

The aim of the study is to evaluate the effect of changing selected body positions on oxygen saturation among patients with acute stroke.

Subjects and methods:

Research design:

Quasi-experimental research design utilized in this study.

Subjects (Sample):

A Purposive sample of (60) adult patients were admitted to ICU with a diagnosis of acute stroke.

For the sample size n, this calculator employs the following formula:

 n = N*X / (X + N – 1),

Where,

X = Z_α/2² ­*p*(1-p) / MOE²,

and Z/2 is the critical value of the Normal distribution at /2 (for example, for a 95percent confidence level, is 0.05 and the critical value is 1.96), MOE is the margin of error, p is the sample proportion, and N is the participant scale. The sample size formula (n=60) has been subjected to a Finite Population Correction.

Inclusion Criteria:

Aged over 18 -64years, patients with the acute phase of stroke (24-48 hours), and attached with a pulse oximeter to monitor oxygen saturation

Exclusion criteria:

Patients with carbon monoxide poisoning, pyrexia, patients with chronic lung disease, patients with unstable cardiovascular disease, a poor peripheral perfusion especially in the hands, anemia and acute respiratory infection.

Setting:

The study conducted in intensive care unit (ICU) at Aswan University Hospital.

Study duration:

The total data collection collected for seven months from October 2018 to Abril 2019.

Study tools:

Four tools designed and used for collecting data for this study, these tools prepared and tested by the researcher, and content of the tools established after extensive literature review.

First Tool: Structured Interview questionnaire sheet, it includes (two parts): 1^st part: Sociodemographic characteristics of the patients: It is including socio demographic data such as, age, gender, marital status, level of education, date of admission etc……)2 ^nd part: (A) Medical history:It constructed and developed by the researcher based reviewing of literature to assess past and present medical history of the patient and family of the same disease, side of hemiparesis, smoking habits etc…) (B): Current health status: It constructed and developed by the researcher based reviewing of literature to assessrespiratory pattern, stroke classification, oxygen treatment, pulse etc….). (Anderson et al.,2019) (Lam et al.,2019) (Tan et al., 2020)

Second Tool: Glasgow Coma Scale (GCS): Second Tool: Glasgow Coma Scale (GCS): This scale was developed by (Teasdale et al., 1974). A neurological scale aims to give a reliable and objective way of recording the conscious state of a person for initial as well as subsequent assessment. It is composed of three parameters: Best Eye Response, Best Verbal Response, and Best Motor Response. The GCS is scored between 3 to 15 and 3 being the worst, and 15 the best. Coma Score of 13 or higher correlates with a mild brain injury; 9 to 12 is a moderate brain injury and 8 or less a severe brain injury.

Third Tool: Scandinavian Stroke Scale (SSS): This scale was developed by (Scandinavian Stroke Study Group. 1985). The SSS is currently utilized to predict the severity of the neurological impairment (stroke severity). SSS has nine items include Consciousness, Eye movement, Arm/hand/leg motor power (each assessed only on the affected side), Orientation, Speech, Facial palsy, and Gait.

Scoring system: The SSS scale’s minimum score is ‘0’ and the maximum ‘58’. The whole score was categorized into 4 levels of stroke severity: 1) from 0-18 described as (Very severe stroke). 2) From (19 to 32) is considered Severe stroke, from (33–44) refers to moderate stroke, and the score of 45–58 refers to mild stroke

Fourth Tool: Oxygen saturation monitoring record: It was developed by the researcher to monitor the patient's oxygen saturation. Oxygen saturation was monitored by using a pulse oximeter for all patients. Monitoring was done before; during and immediately after changing positions, changing position every one hour for all stroke patients in selected position, and oxygen saturation monitoring will be done every 15 minutes for each test position  (supine, right side, left side, Simi sitting)  positions. 

Tools Validity and reliability:

• The study tools were developed after reviewing the related literature. To determine face validity, these tools were tested by a Jury committee that consists of five medical surgical-nursing experts. Recommendations were followed; the questions that were not appropriate were taken out and some questions needed clarification and modifications were done.
• Tools reliability was done to identify the extent of tools items were measurable with study concept and correlation with each other using Cronbach’s Alpha test. 
• Cronbach’s Alpha reliability of GCS was (0.875) andreliability for SSS was (0.817).

Pilot study:

A pilot study was carried out on six patients (10.0%) who were admitted to ICU at Aswan University Hospital, who fulfilled the inclusion criteria to test the feasibility, objectivity, applicability of the study tools, and to estimate the needed time to fill the data collection. Based on the results of the pilot study, no refinement/ modifications were done for data collection instruments; patients who shared in the pilot study were included in the actual study sample.

Ethical consideration:

Ethical Approval was taken from the scientific ethical committee in the faculty of nursing at Minia University. Official permission was obtained from the head of ICU to conduct the study at Aswan University Hospital. Oral consent was obtained prior to enrollment. In the event that patients were unable to give oral consent due to aphasia or mental status changes, consent was obtained from a legally authorized representative. The purpose and nature of the study explained to all patients and they could withdraw at any time of the study. Only patient records meeting the inclusion criteria of the study were included in the study. Data assured confidentiality and anonymity of information protected. Ethics, values, culture, and beliefs respected.

Study Procedure:

• All patients included in the study were informed about the aim of the study & all of them gave oral or written informed consent before engaging in the study if possible and they could withdraw at any time of the study.
• The researcher fulfilled socio-demographic data and medical history sheet, then vital signs were measured and recorded before putting the patient in any position, then the GCS Scale was measured to assess the patient’s consciousness level then the SSS Scale were measured to assess patient’s severity of stroke.
• The patient was put in four positions (semi-sitting, supine, right side & left side position), patients still in each position were included in the study for one hour, during this hour SaO2was measured & recorded every 15 minutes for all patients before, during and immediately after changing positions in that hour by using a pulse oximeter.
• Positions sequence determined by a modified randomization procedure to avoid ordering effects, if the patient was already in the test position or one closely approximating to it, this position was excluded from the randomization process at this stage and this position was included in the process when the next position was selected.

Limitation of the study:

Research findings can’t be generalized because of the small sample size among patients with acute stroke, lack of previous research studies on the topic, and time for data collection is a problem for some patients to still in the same position for a long time.

Statistical analysis:

The collected data organized categorized, tabulated, and analyzed using SPSS ver. 24. Data presented in tables and charts using numbers and percentages, statistics and associations have done using mean, standard deviation SD, t-test and P-value Significant of the result: no Significant if p->0.05, Significant if p-<0.05 and Highly Significant if p-<0.001

Results:

Table (1): Frequency distribution of the studied sample regarding their sociodemographic characteristics (n = 60).

Table (1) shows that 60.0% of the studied sample aged between 50- 60 years, 53.3% of them were male, 71.7% of them were married, 43.3% of them had read and write, and 51.7% of them were housewives.

Table (2): Mean and standard deviation for vital signs of the studied sample (n = 60).

Table (2) presents that the mean score of systolic and diastolic blood pressure, patient heart rate, their body temperature, and their respiration was more stable in the 4th 15 minutes of first hours after position change with highly statistically significant differences.

Figure (1): illustrated the total grades of Glasgow Coma Scale, more than two third of studied sample was moderate brain injury.

Figure (2): illustrates the Total Grades of Scandinavian Stroke Scale , 46.7% of the studied sample can be had a severe stroke, 38.3% of them had a very severe stroke, and 15.0% of them had a moderate stroke. 

Table (3): Mean and standard deviation of SaO2 during total one hour spending in each position of studied sample (n= 60).

*= Statistically significance differences **= Highly statistically significance differences

Table (3) : illustrated Oxygen saturation monitoring, the present study results founded that the highest mean score of O2 saturation in semi sitting position was higher than anther (Supine, Right, and Left) positions.

Figure (3): present that, the mean score of SaO2 at 2nd 15 min, 3rd 15 min, 4th min, and mean SaO2 of one hour at the semi-sitting position was higher than different positions (Supine position, Right side position, and Left side position) with statistically significant differences with p-value .008, .05, .002, and .019 respectively, the semi-sitting position was the best position of all position.

Table (4): Correlation between oxygen saturation and (Semi setting position, Supine position, Right, Left side) positions.

Table (4): Shows that there was a significant positive correlation between oxygen saturation and Semi setting position.