Table of Contents  
ORIGINAL ARTICLE
Year : 2016  |  Volume : 10  |  Issue : 1  |  Page : 12-16

Addition of dexamethasone to magnesium decreases atrial fibrillation following coronary artery bypass grafting surgery


1 Department of Anesthesiology, Ain Shams University, Cairo, Egypt
2 Department of Cardiothoracic Surgery, Ain Shams University, Cairo, Egypt

Date of Submission11-Jun-2015
Date of Acceptance31-May-2016
Date of Web Publication1-Jun-2016

Correspondence Address:
Hoda Shokri
PhD, MD, Department of Anesthesiology, Ain Shams University, Abbassya Square, 11772 Cairo
Egypt
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/1687-9090.183173

Rights and Permissions
  Abstract 

Objective
Atrial fibrillation (AF) is a frequent complication that occurs within the first 5 days after cardiac surgery with a reported incidence of 20-40%. It might lead to significant morbidity, such as stroke and myocardial infarction. This prospective study aims to assess the potential benefit of adding a standard dose of dexamethasone to intravenous magnesium (Mg) in the case of AF after coronary artery bypass grafting (CABG).
Patients and methods
This was a prospective, randomized, parallel group study conducted in Ain Shams University Hospital.
One hundred patients scheduled for elective primary isolated CABG were included. All patients had a preoperative sinus rhythm.
Patients in the dexamethasone plus magnesium (DMg) group (50 patients) received two doses of intravenous dexamethasone (6 mg each) along with two doses of Mg supplementation (2 g each) within the first postoperative day.
Patients in the Mg-only group (50 patients) received two doses of Mg supplementation (2 g each) at the similar time as patients in the DMg group.
Continuous ECG recording was carried out for the first 72 h for all patients. Incidence of postoperative complications caused by dexamethasone was recorded.
Measurements and main results
All patients (50 in each group) completed the study. There was no significant difference between the two study groups with regard to demographic data, preoperative comorbidities, and surgical factors. The incidence of postoperative AF was significantly lower in the DMg group (P < 0.05) compared with the Mg-only group. There was no significant difference between the study groups regarding duration of postoperative ICU stay and extubation time. There was no significant difference between the study groups regarding incidence of chest infection (P = 0.7), sternal wound infection (P = 0.5), and urinary tract infection (P = 0.6).
Conclusion
Addition of dexamethasone (12 mg) to MgSO 4 (2 g) seems to decrease the incidence of new-onset AF in primary isolated elective CABG surgery without an increased incidence of complications.

Keywords: Atrial fibrillation, coronary artery bypass grafting, cardiac surgery, dexamethasone, magnesium


How to cite this article:
Shokri H, Ali I, Hassouna A. Addition of dexamethasone to magnesium decreases atrial fibrillation following coronary artery bypass grafting surgery. Egypt J Cardiothorac Anesth 2016;10:12-6

How to cite this URL:
Shokri H, Ali I, Hassouna A. Addition of dexamethasone to magnesium decreases atrial fibrillation following coronary artery bypass grafting surgery. Egypt J Cardiothorac Anesth [serial online] 2016 [cited 2019 Nov 20];10:12-6. Available from: http://www.ejca.eg.net/text.asp?2016/10/1/12/183173


  Introduction Top


New-onset postoperative atrial fibrillation (AF) is the most common postoperative complication after coronary artery bypass grafting (CABG) surgery, with a reported incidence of 20-40% [1]. It is associated with postoperative morbidities such as cerebrovascular complications and infections (e.g. septicemia, pneumonia, and mediastinitis), which are associated with prolonged hospital stay and increased costs [2],[3]. Obesity, male sex, chronic obstructive pulmonary disease, advanced age, hypertension, prior history of AF, preoperative use of digoxin or milrinone, or increased incidence of electrolyte imbalance such as hypomagnesemia or hypokalemia following cardiac surgery increase the risk of developing postoperative AF [4]. Cardiac surgery with extracorporeal circulation is known to be associated with systemic inflammatory response [5], which may be in part responsible for postoperative AF. Complement and C-reactive protein complex levels and the number of white blood cell markers of inflammatory reactions are elevated in patients who develop AF [6]. Thus, corticosteroid prophylaxis in cardiac surgery has been used for about 30 years. The aim of our study was to compare the effectiveness of dexamethasone (12 mg) when combined with magnesium (Mg) (2 g) intravenous infusion on prophylaxis of AF following cardiac surgery.


  Patients and methods Top


After obtaining the approval of medical ethical committee of Ain Shams University, 100 patients scheduled for primary isolated elective on-pump CABG surgery at Ain Shams University Hospital (Cairo, Egypt) were enrolled in this study. All patients were of physical status ASA II-III, with normal sinus rhythm. This prospective randomized parallel group study was conducted in 2014. Exclusion criteria included the need for emergency surgery, previous episodes of AF, history of myocardial infarction or renal failure, uncontrolled diabetes mellitus, active tuberculosis (TB), or known allergy, and contraindication to steroids. Patients taking calcium channel blockers, previous magnesium sulfate (MgSO 4 ), steroids, or inotropes were also excluded.

After obtaining written informed consent from all patients, they were randomized by means of closed envelopes into two equal groups: the Mg-only group and the dexamethasone plus magnesium (DMg) group. Patients in the Mg-only group received intravenous infusion of MgSO 4 (2 g) dissolved in 100 ml saline over 5 min in the postsurgical cardiac ICU for 2 days. Patients in the DMg group received intravenous dexamethasone (12 mg) in addition to the same dose of MgSO 4 .

In the preparation room the anesthesiologist secured an 18-G cannula and administered intravenous midazolam 0.05 mg/kg and started an infusion of Ringer's acetate. Standard monitoring was initiated in the form of a five-lead ECG with ST-segment monitoring, pulse oximetry, end tidal CO 2 and invasive arterial blood pressure monitoring, and assessment of nasopharyngeal and skin temperature and urine output. Before induction of anesthesia, a baseline laboratory evaluation was carried out, including prothrombin time, hemoglobin, hematocrit, and fibrinogen level. Anesthesia was induced using thiopental (5-7 mg/kg) and fentanyl (5 mg/kg). Pancuronium (0.08 mg/kg) was used to facilitate endotracheal intubation. Patients were mechanically ventilated in volume-controlled mode to maintain the end expiratory CO 2 at 34-36 mmHg. Anesthesia was maintained with isoflurane 1.2%. Fentanyl (3-5 mg/kg) and pancuronium bromide 0.01 mg/kg were given.

Surgeries were performed on all patients by the same surgical team. Systemic heparinization was carried out before institution of cardiopulmonary bypass (CPB) using unfractionated heparin at an initial dose of 300 IU/kg. A celite activated clotting time above 400 was targeted before institution of CPB. CPB was instituted using Sarns Machine (Harrison, Michigan, USA) primed with 1500 ml of lactated Ringer's solution at a flow rate of 2.6 l/min/m 2 and a Trillium Affinity NT Oxygenator (Medtronic, Minneapolis, USA). Mild hypothermia (32°C) was maintained during CPB. Myocardial protection was achieved with cold cardioplegic solution (20°C). During CPB, homologous packed red blood cells were transfused if hemoglobin concentration was below 6 g/dl. The effect of heparin was reversed at the end of CPB with protamine 1 mg for every 100 U of heparin administered.

Following transfer to the ICU, all patients had their ECG continuously monitored for 72 h. The incidence of AF was documented. Episodes of atrial flutter and supraventricular tachycardia were not included in the study. Four hours after admission into the ICU, all patients (in both groups) received an intravenous infusion of MgSO 4 (2 g), dissolved in 100 ml saline, over 5 min. On the morning of day 1, patients received a second dose of intravenous infusion of MgSO 4 (2 g) dissolved in 100 ml saline over 5 min. Patients in the DMg group also received intravenous dexamethasone (6 mg) in addition to MgSO 4 following the same regimen. On the morning of day 1, all patients (in both groups) received a second dose of intravenous infusion of MgSO 4 (2 g), dissolved in 100 ml saline, over 5 min. Patients in the DMg group received a second dose of intravenous dexamethasone (6 mg). The following dose regimen was followed for amiodarone. Amiodarone was started at 150 mg loading dose and maintained at 60 mg/h for the first 6 h and at 30 mg/h for the remaining 72 h and continued at 200 mg/day orally for 15 days after discharge for patients who still had AF.

The primary outcome was the incidence of AF in the first 72 h following surgery. AF was defined as an episode lasting longer than 5 min irrespective of the need for active treatment. The numbers of patients who recovered spontaneously or required treatment (amiodarone+electrical cardioversion) were recorded. Secondary outcomes included extubation time, length of stay, and the incidence of steroid-related complications such as infection of sternal wound, chest infection, and urinary tract infection.

Statistical analysis

Statistical software programs Statistical Package for the Social Sciences, version 17 (SPSS Inc., Chicago, Illinois, USA), at 95% confidence interval and power of 80% with an a error of 5%, were used for the analysis of data. Sample size calculation was based on the protocol followed in another study by Abbaszadeh et al. [7]. Results of continuous measurements were presented as mean ± SD and results of categorical measurements were presented as number and percentage. A P-value less than 0.05 was considered to be significant.

The Student t-test was used to determine the significance of the study parameters between the two groups of metric parameters. The χ2 test/Fisher's exact test was used to determine the significance of the study parameters on a categorical scale between two or more groups.


  Results Top


All patients (50 in each group) completed the study. There was no significant difference in patients' demographic data, preoperative comorbidities, or surgical factors between the two groups [Table 1].
Table 1: Demographic data, risk factors, and surgical factors

Click here to view


Four and 11 patients developed AF in the DMg and Mg groups, respectively [Table 2]. Patients in the DMg group had a significantly lower incidence of AF than did patients in the Mg-only group during the first 72 h after CABG. Management of AF is detailed in [Table 2]. There was no significant difference between the study groups regarding duration of postoperative ICU stay and extubation time.
Table 2: Comparison of the incidence of atrial fibrillation, duration of postoperative intensive care unit, and extubation time between the study groups

Click here to view


Regarding the incidence of chest infection, sternal wound infection, and urinary tract infection, there was no significant difference between the patients in both groups [Table 3]. All studied patients were discharged from the ICU on the first postoperative day and from the hospital on the sixth or seventh postoperative day.
Table 3: Descriptive table showing the incidence of postoperative complications from steroids

Click here to view



  Discussion Top


AF is the most common arrhythmia after cardiac surgery. Its incidence varies depending on the type of surgery. Postoperative AF may cause hemodynamic deterioration predisposing to stroke and increased mortality. Effective prophylaxis of postoperative AF might reduce hospitalization and overall morbidities [8].

This study was conducted to find out a better way to decrease the incidence of new-onset AF during the first 3 days after CABG. The doses of dexamethasone and Mg were based on the current literature. In this prospective randomized clinical trial, patients who received intravenous DMg had significantly less incidence of postoperative AF compared with patients who received Mg only.

Previous studies have found several confounding factors of AF after cardiac surgery [9]. Thus, we adjusted other independent factors such as age, sex, and number of grafts. Kohno et al. [10] compared the incidence of AF in 100 patients who received a daily infusion of 10 mmol of MgSO 4 for 3 days after surgery with the incidence in another 100 patients who did not receive MgSO 4 . The incidence of postoperative AF was significantly lower in the Mg group compared with the untreated group (P = 0.001) [10]. Toraman et al. [11] performed a randomized controlled study in 200 patients by giving them 6 mmol of Mg both preoperatively and postoperatively. Only 2% of patients receiving Mg developed AF compared with 21% in the control group [11]. This was different from our study, as we administered MgSO 4 with or without dexamethasone only postoperatively. Halonen et al. [12] showed that there was a significant decrease in the incidence of AF after the administration of 100 mg hydrocortisone compared with placebo. Corticosteroid treatment remained a significant independent predictor of the absence of postoperative AF.

Increased risk for complications such as wound infections and stress ulcer could be a concern with corticosteroid therapy [13]. We found that administration of dexamethasone (12 mg) was feasible and well tolerated and noted no serious complications associated with intravenous administration of corticosteroids. Prasongsukarn et al. [14] showed that there was significant decrease in the incidence of AF after administration of intravenous methylprednisolone (100 mg) before surgery and 4 mg of dexamethasone intravenous every 6 h for 1 day after surgery compared with placebo (P = 0.003) without development of remarkable complications.

In another study, Ho and Tan [15] showed that corticosteroid prophylaxis significantly reduced the risk of AF (P < 0.01) and length of stay in the ICU (P < 0.01) and hospital stay (P = 0.03), compared with placebo. The use of corticosteroids was not associated with an increased risk for infection (P = 0.73), but hyperglycemia requiring insulin infusion after corticosteroid prophylaxis was common (P < 0.01) [15].

A meta-analysis showed that intravenous Mg significantly reduced the incidence of postoperative AFs after CABG. This finding encourages the use of intravenous Mg to prevent postoperative AFs after CABG [16].

Van Osch et al. [17] showed that there was no statistically significant difference in the incidence of postoperative AFs between the dexamethasone group and the placebo group (P = 0.14).

This disagreed with our findings.

The major limitation of our study was related to the lack of blinding as it leaves the trial open to observer bias. We suggest further prospective double-blind trials on other cardiac procedures adopting the same treatment medications.


  Conclusion Top


Addition of dexamethasone (12 mg) to MgSO 4 (2 g) seems to decrease the incidence of new-onset AF in primary isolated elective CABG surgery but with few potential side effects.

Acknowledgements

This work was supported by the department of Cardiothoracic Surgery and the department of Anesthesiology at Ain Shams University, Cairo, Egypt.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

 
  References Top

1.
Abbaszadeh M, Khan ZH, Mehrani F, Jahanmehr H. Perioperative intravenous corticosteroids reduce incidence of atrial fibrillation following cardiac surgery: a randomized study. Rev Bras Cir Cardiovasc 2012; 27:18-23.  Back to cited text no. 1
    
2.
Almassi GH, Schowalter T, Nicolosi AC, Aggarwal A, Moritz TE, Henderson WG, et al. Atrial fibrillation after cardiac surgery: a major morbid event? Ann Surg 1997; 226:501-511; discussion 511-513.  Back to cited text no. 2
    
3.
Hogue CW, Creswell LL, Glutterman DD, Fleisher LA American College of Chest Physicians. Epidemiology, mechanics and risks: American College of Chest Physicians guidelines for the prevention and management of postoperative atrial fibrillation after cardiac surgery. Chest 2005; 128:9S-16S.  Back to cited text no. 3
    
4.
Hayashida N, Shojima T, Yokokura Y, Hori H, Yoshikawa K, Tomoeda H, Aoyagi S. P-wave signal-averaged electrocardiogram for predicting atrial arrhythmia after cardiac surgery. Ann Thorac Surg 2005; 79:859-864.  Back to cited text no. 4
    
5.
Ishii Y, Schuessler RB, Gaynor SL, Yamada K, Fu AS, Boineau JP, Damiano RJ Jr. Inflammation of atrium after cardiac surgery is associated with inhomogeneity of atrial conduction and atrial fibrillation. Circulation 2005; 111:2881-2888.  Back to cited text no. 5
    
6.
Morariu AM, Loef BG, Aarts LP, Rietman GW, Rakhorst G, van Oeveren W, Epema AH. Dexamethasone: benefit and prejudice for patients undergoing on-pump coronary artery bypass grafting: a study on myocardial, pulmonary, renal, intestinal, and hepatic injury. Chest 2005; 128:2677-2687.  Back to cited text no. 6
    
7.
Abbaszadeh M, Khan ZH, Mehrani F, Jahanmehr H. Perioperative intravenous corticosteroids reduce incidence of atrial fibrillation following cardiac surgery: a randomized study. Rev Bras Cir Cardiovasc 2012; 27:18-23.  Back to cited text no. 7
    
8.
Nair G. Atrial fibrillation after cardiac surgery. Ann Card Anaesth 2010; 13:196-205.  Back to cited text no. 8
[PUBMED]  Medknow Journal  
9.
Aranki SF, Shaw DP, Adams DH, Rizzo RJ, Couper GS, VanderVliet M, et al. Predictors of atrial fibrillation after coronary artery surgery. Current trends and impact on hospital resources. Circulation 1996; 94:390-397.  Back to cited text no. 9
    
10.
Kohno H, Koyanagi T, Kasegawa H, Miyazaki M. Three day Mg administration prevent AF after CABG. Ann Thorac Surg 2005; 79:117-126.  Back to cited text no. 10
    
11.
Toraman F, Karabulut EH, Alhan HC, Dagdelen S, Tarcan S. Magnesium infusion dramatically decreases the incidence of atrial fibrillation after coronary artery bypass grafting. Ann Thorac Surg 2001; 72:1256-1261; discussion 1261-1262.  Back to cited text no. 11
    
12.
Halonen J, Halonen P, Järvinen O, Taskinen P, Auvinen T, Tarkka M, et al. Corticosteroids for the prevention of atrial fibrillation after cardiac surgery: a randomized controlled trial. JAMA 2007; 297:1562-1567.  Back to cited text no. 12
    
13.
Bruton LL, Lazo JS, Parker KL. The pharmacological basis of therapeutics. 11th ed. New York: McGraw-Hill Medical Publishing Division, 2006.  Back to cited text no. 13
    
14.
Prasongsukarn K, Abel JG, Jomieso WR, Cheng A. The effects of steroids on the occurrence of postoperative atrial fibrillation after coronary artery bypass grafting surgery: a prospective randomized trial. J Thorac Cardiovasc Surg 2005; 130:93-98.  Back to cited text no. 14
    
15.
Ho KM, Tan JA. Benefits and risks of corticosteroid prophylaxis in adult cardiac surgery: a dose-response meta-analysis. Circulation 2009; 119:1853-1866.  Back to cited text no. 15
    
16.
Gu WJ, Wu ZJ, Wang PF, Aung LH, Yin RX. Intravenous magnesium prevents atrial fibrillation after coronary artery bypass grafting: a meta-analysis of 7 double-blind, placebo-controlled, randomized clinical trials. Trials 2012; 13:41.  Back to cited text no. 16
    
17.
17 van Osch D, Dieleman JM, van Dijk D, Jacob KA, Kluin J, Doevendans PA, Nathoe HM, DExamethasone for Cardiac Surgery (DECS) study group; Dexamethasone for Cardiac Surgery DECS study group. Dexamethasone for the prevention of postoperative atrial fibrillation. Int J Cardiol 2015; 182:431-437.  Back to cited text no. 17
    



 
 
    Tables

  [Table 1], [Table 2], [Table 3]



 

Top
 
 
  Search
 
Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
Access Statistics
Email Alert *
Add to My List *
* Registration required (free)

 
  In this article
Abstract
Introduction
Patients and methods
Results
Discussion
Conclusion
References
Article Tables

 Article Access Statistics
    Viewed1006    
    Printed53    
    Emailed1    
    PDF Downloaded145    
    Comments [Add]    

Recommend this journal


[TAG2]
[TAG3]
[TAG4]