@2025 Afarand., IRAN

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ISSN: 2252-0805    The Horizon of Medical Sciences 2014;20(2):87-92

Background
Coronary artery bypass grafting is an effective treatment method in elimination of coronary artery stenosis, and it has better treatment effects [1, 4-8]. … [2, 3]. Suctioning by an incorrect method leads to complications such as cardiac arrhythmias and blood oxygen loss [9, 10]. Selection of correct method for suctioning is helpful in reduction of complications [11]. … [12-14]. Open and closed suctioning are two methods of trachea airway suctioning. Open suctioning, in case of separation of patient from mechanical ventilation, might lead to considerable oxygen loss [15], while in closed suctioning there is continuous oxygen flow, which leads to fewer respiratory complications [16].
Previous Studies
According to some researchers, there is less reduction in arterial oxygen pressure in closed suctioning, while this method has been questioned by some other researchers [9, 17].
Aim(s)
The study aimed at comparison between the effects of open and closed endotracheal suctioning on hemodynamic factors of patients after coronary artery bypass grafting under mechanical ventilation.
Research type
This is a single-blind clinical trial study.
Research society, place and time
Hospitalized in the open-heart surgery ICU of Imam Reza Hospital of Mashhad, Iran, in 2013, the patients, meeting the criteria of the study and needing for endotracheal airway suctioning after coronary artery bypass grafting, were studied.
Sampling method and number
Based on inclusion and exclusion criteria, at the first stage, 130 patients were selected, using convenience nonprobability sampling method; and at the second stage, they were divided into two groups, using random allocation. The inclusion criteria were as the followings: No primary pulmonary pathology – age more than 18 years – no cardiac dysrhythmia – hemodynamic stability – no intracranial hypertension – PEEP less than 10cm water– FiO_2 less than 60% – appropriate sedation (RASS=0 and -1) The exclusion criteria were as the followings: New brain complications – dysrhythmia – dangerous heart complications– oximetry decline during suctioning The sample size for each group was considered 48 persons, regarding test-power 80, confidence coefficient 95% (0.05 Alpha), and maximum one unit clinical accuracy. Finally, in order to enhance the test-power, the sample sizes for ‘control’ and ‘case’ groups were considered 75 and 55 persons, respectively.
Used devices&materials
To collect data, a personal information form was used, of which the validity was determined with content validity method and completed by the researcher. Equivalent reliability was used to determine the reliability. Mechanical ventilation was done for all patients, through SIMV (volume mode), 8ml per kg current volume, 10-12 per min breathing, 1.5sec inhalation, 40-60% FiO_2, 5 to 10cm water PEEP, and 10cm PVS. The patients’ heartbeat and mean arterial pressure were measured and recorded, using invasive method. After giving 100% oxygen for 60 seconds, 15 seconds airway suctioning was done, using appropriate size suction (according to trachea pipe number), through open or closed methods (using the random number table randomly). Heartbeat and mean arterial pressure were measured during suctioning and immediately after suctioning; and then, it was done each minute of five minutes. Data were collected, using observation, recoding, and intervening method. Data were analyzed, by SPSS 16 software. One-way ANOVA test was used to compare mean arterial pressure with heartbeat in open and closed methods. Before and after intervention, mean heartbeat and mean arterial pressure in open suctioning group were compared with closed suctioning group, using Paired-T test. Based on the suctioning type, at different times and in each group, mean arterial pressure was compared with heartbeat, using One-way ANOVA test with repeated measures. In addition, to evaluate demographic information and physical characteristics, Independent-T test was used.
Findings by Text
79 (60.8%) and 51 (39.2%) persons were male and female, respectively. Mean age was 60.86±13.32years, with 55 to 64 years age range. There was no significant difference in age, sex, weight, height, and body mass index (BMI) between two groups, and groups were homogeneous statistically (Table 1). In addition, there was no significant correlation between personal variables and mean difference between mean arterial pressure and heartbeat, in open and closed suctioning methods. There was no significant difference between mean values of mean arterial pressure and heartbeat before, during, and after suctioning, and each minute of five minutes after it, in open and closed suctioning groups. Mean arterial pressure change was significant before suctioning and during every stage after suctioning in open and closed suctioning groups. In addition, heartbeat before suctioning and during every stage after suctioning with open and closed systems was significant. Despite the fact that the ends (before intervention and at the end of the study) were approximately equal, but changes were formed as horseshoes in two groups (Table 2).
Main comparison to the similar studies
It has been shown that heartbeat after open suctioning reaches its base state 3 minutes earlier than closed suctioning, and mean arterial pressure returns to the base state at the fifth minute in both suctioning systems equally, with similar changes after open and closed suctioning [11]. These are consistent with the results of the present study. It has been stated that there is only significant difference in arterial mean pressure after open suctioning in patients with severe pulmonary injuries, while measurements of hemodynamic indices before and immediately after suctioning and each minute of 5 minutes shows no significant difference between mean arterial pressure and heartbeat [18]. These are different from the results of the present study. The results are consistent with reported results showing no significant difference between two suctioning systems in the items before, during, and 5 minutes after suctioning [19]. The results, also, inconsistent with stated results showing enhancement in the items in open suctioning than closed suctioning [20, 21]. More arrhythmia due to open suctioning has been reported [20, 22], which is inconsistent with the present study. According to another study, there is no arrhythmia, except sinus tachycardia [23].
Suggestions
It is suggested that the impacts of open and closed suctioning on hemodynamic indices of patients with no hemodynamic stability receiving isotope or vasopressor to be evaluated.
Limitations
Hemodynamic stability of the patients was one of the limitations of the present study.
Conclusions
In patients with coronary artery bypass grafting, open and closed suctioning of trachea and bronchioles under standard and true conditions affects hemodynamic indices equally and has no dangerous and severe arrhythmia. Therefore, one system could not be preferred over the other.
Acknowledgments
The researchers feel grateful to personnel of ICU of Imam Reza Hospital.
Conflict of interest
Non-declared
Ethical Permissions
Ethical confirmation was registered by Ethic Committee of Gonabad University of Medical Sciences. It was registered by code no. IRCT2013042713134N1 in Iran Registration of Clinical Trials.
Funding Sources
The paper is derived from MSc thesis, confirmed by Higher Education and Research Council of Gonabad University of Medical Sciences in 2013.

TABLES and CHARTS

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