2024 European Heart Rhythm Association/Heart Rhythm Society/Asia Pacific Heart Rhythm Society/Latin American Heart Rhythm Society expert consensus statement on catheter and surgical ablation of atrial fibrillation.

In the last three decades, ablation of atrial fibrillation (AF) has become an evidence-based safe and efficacious treatment for managing the most common cardiac arrhythmia. In 2007, the first joint expert consensus document was issued, guiding healthcare professionals involved in catheter or surgical AF ablation. Mounting research evidence and technological advances have resulted in a rapidly changing landscape in the field of catheter and surgical AF ablation, thus stressing the need for regularly updated versions of this partnership which were issued in 2012 and 2017. Seven years after the last consensus, an updated document was considered necessary to define a contemporary framework for selection and management of patients considered for or undergoing catheter or surgical AF ablation. This consensus is a joint effort from collaborating cardiac electrophysiology societies, namely the European Heart Rhythm Association, the Heart Rhythm Society (HRS), the Asia Pacific HRS, and the Latin American HRS.

Multiple sclerosis and the incidence of venous thromboembolism: a systematic review and meta-analysis.

A number of studies have suggested that multiple sclerosis (MS) can be associated with serious vascular complications, for which pulmonary thromboembolism (PTE) is a potentially lethal complication. The purpose of this study is to establish a current literature-based estimate of the incidence of venous thromboembolism (VTE), deep vein thrombosis (DVT), and PTE in patients with MS (pwMS) due to the lack of systematic reviews and meta-analyses on this topic. In this systematic review and meta-analysis, studies were assessed regarding the association between MS and the incidence of VTE. The studies were identified through a systematic search of major electronic databases spanning the period from 1950 to February 2022. A random-effects analysis was conducted to calculate the pooled effect size (ES) and 95% confidence intervals (CI) using STATA software. Nine out of 4605 studies were included in the meta-analysis, with an overall sample size of 158,546 individuals. Meta-analysis revealed that the pooled incidence of VTE was 1.8% (95% CI 1.4-2.3) among pwMS. Also, there was an incidence of 0.9% (95% CI 0.4-1.4) and 1.5% (95% CI 1-2.2) for PTE and DVT, respectively in pwMS. Analysis showed MS would be significantly associated with a twofold increased risk of VTE [risk ratios (RR) = 2.12 (95% CI 1.53-2.93)]. Although MS is not typically considered a major risk factor for VTE, the meta-analysis of cohort studies shows that MS has a relative association with an increased incidence of VTE. Future research should focus on the investigation of the effects of MS and its treatments on VTE risk, and also a full range of confounding adjustments will be needed.

Epidemiology and prevalence of tobacco use in Tehran; a report from the recruitment phase of Tehran cohort study.

INTRODUCTION: Tobacco use is a major health concern worldwide, especially in low/middle-income countries. We aimed to assess the prevalence of cigarette smoking, waterpipe, and pipe use in Tehran, Iran. METHODS: We used data from 8272 participants of the Tehran Cohort Study recruitment phase. Tobacco use was defined as a positive answer to using cigarettes, waterpipes, or pipes. Participants who did not report tobacco use during the interview but had a previous smoking history were categorized as former users. Age- and sex-weighted prevalence rates were calculated based on the national census data, and characteristics of current and former tobacco users were analyzed. RESULTS: Age- and sex-weighted prevalence of current tobacco users, cigarette smokers, waterpipe, and pipe users in Tehran was 19.8%, 14.9%, 6.1%, and 0.5%, respectively. Current tobacco use was higher in younger individuals (35-45 years: 23.4% vs. ≥ 75 years: 10.4%, P < 0.001) and men compared to women (32.9% vs. 7.7% P < 0.001). The prevalence of tobacco use increased with more years of education (> 12 years: 19.3% vs. illiterate: 9.7%, P < 0.001), lower body mass index (< 20 kg/m2: 31.3% vs. ≥ 35 kg/m2: 13.8%, P < 0.001), higher physical activity (high: 23.0% vs. low: 16.4%, P < 0.001), opium (user: 66.6% vs. non-user: 16.5%, P < 0.001), and alcohol use (drinker: 57.5% vs. non-drinker: 15.4%, P < 0.001). Waterpipe users were younger (46.1 vs. 53.2 years) and had a narrower gender gap in prevalence than cigarette smokers (male/female ratio in waterpipe users: 2.39 vs. cigarette smokers: 5.47). Opium (OR = 5.557, P < 0.001) and alcohol consumption (OR = 4.737, P < 0.001) were strongly associated with tobacco use. Hypertension was negatively associated with tobacco use (OR = 0.774, P = 0.005). CONCLUSION: The concerning prevalence of tobacco use in Tehran and its large gender gap for cigarette and waterpipe use warrant tailored preventive policies.

A randomized trial of non-fasting vs. fasting for cardiac implantable electronic device procedures (Fast-CIED Study).

AIMS: Data on safety and efficacy of a non-fasting strategy in minimal invasive cardiac procedures are lacking. We assessed a non-fasting strategy compared with a fasting strategy regarding patient's well-being and safety in elective cardiac implantable electronic device (CIED) procedures. METHODS AND RESULTS: In this randomized, single-blinded clinical trial, 201 patients (non-fasting = 100, fasting = 101) with a mean age of 72.0 ± 11.6 years (66.7% male) were assigned to a non-fasting strategy (solids/fluids allowed up to 1 h) or a fasting strategy (at least 6 h no solids and 2 h no fluids) before the procedure and analysed on an intention-to-treat basis. The co-primary outcomes were patients' well-being scores (based on numeric rating scale, 0-10) and incidence of intra-procedural food-related adverse events, including vomiting, perioperative pulmonary aspiration, and emergency intubation. Renal, haematological, and metabolic blood parameters and 30-day follow-up data were gathered. The summed pre-procedural patients' well-being score was significantly lower in the non-fasting group [non-fasting: 13.1 ± 9.6 vs. fasting: 16.5 ± 11.4, 95% confidence interval (CI) of mean difference (MD) -6.35 to -0.46, P = 0.029], which was mainly driven by significantly lower scores for hunger and tiredness in the non-fasting group (non-fasting vs. fasting; hunger: 0.9 ± 1.9 vs. 3.1 ± 3.2, 95% CI of MD -2.86 to -1.42, P < 0.001; tiredness: 1.6 ± 2.3 vs. 2.6 ± 2.7, 95% CI of MD -1.68 to -0.29, P = 0.023). No intra-procedural food-related adverse events were observed. Relevant blood parameters and 30-day follow-up did not show significant differences. CONCLUSION: These results showed that a non-fasting strategy is beneficial to a fasting one regarding patient's well-being and comparable in terms of safety for CIED procedures (NCT04389697).

Epicardial ablation of ventricular tachycardia in patients with structural heart disease: a single-centre experience over 12 years.

AIMS: Epicardial ablation has risen to an essential part of the treatment of ventricular tachycardias (VTs). In this study, we report the efficacy, risks, and current trends of epicardial ablation in structural heart disease as reported in a tertiary single centre over a 12-year period. METHODS AND RESULTS: Two hundred and thirty-six patients referred for VT ablation underwent a successful epicardial access and were included in the analysis (89% non-ischaemic cardiomyopathy, 90% males, mean age 60 years, mean left ventricular ejection fraction 38.4%). After performing epicardial ablation the clinical VTs were eliminated in 87% of the patients and 71% of the cohort achieved freedom from VT during 22-month follow-up. Twelve patients (5%) suffered major procedure-related complications. Until the end of follow-up 47 (20%) patients died, 9 (4%) underwent a left ventricular assist device implantation and 10 (4%) patients received a heart transplantation. Antiarrhythmic drugs at baseline and during follow-up were independent predictors of VT recurrence. Atrial fibrillation, renal dysfunction, worse New York Heart Association class, and antiarrhythmic drugs at follow-up were associated with worse survival in our cohort. CONCLUSION: In this large tertiary single-centre experience, percutaneous epicardial access was feasible in the large majority of the cohort with acceptably low complications rates. A combined endo-/epicardial approach resulted in 87% acute and 71% long-term success. Further studies are needed to clarify the role of routine combined endo-/epicardial ablation in these complex cardiomyopathies.

Role of assist device implantation and heart transplantation in the long-term outcome of patients with structural heart disease after catheter ablation of ventricular tachycardia.

INTRODUCTION: Ablation of ventricular tachycardias (VTs) in patients with structural heart disease (SHD) has been associated with advanced heart failure and poor survival. METHODS AND RESULTS: This matched case-control study sought to assess the difference in survival after left ventricular assist device (LVAD) implantation and/or heart transplantation (HTX) in SHD patients undergoing VT ablation. From the initial cohort of 309 SHD patients undergoing VT ablation (187 ischemic cardiomyopathy, mean age 64 ± 12 years, ejection fraction of 34 ± 13%), 15 patients received an LVAD and nine patients HTX after VT ablation during a follow-up period of 44 ± 33 months. Long-term survival after LVAD did not differ from the matched control group (p = 0.761), although the cause of lethal events was different. All post-HTX patients survived during follow-up. CONCLUSION: In this matched case-control study on patients with SHD undergoing VT ablation, patients that received LVAD implantation had similar survival compared to the control group after 4­year follow-up, while the patients with HTX had a significantly better outcome.

The Fasa Registry on Systolic Heart Failure (FaRSH): Feasibility Study and the First 5-year Reports.

Background: The literature on patients with heart failure (HF) from the Middle East, besides a few existing registries, is scarce. We report, for the first time in our country, a hospital-based registry for systolic HF. Materials and Methods: This was a web-based registry on HF, conducted in Vali-Asr Hospital affiliated with Fasa University of Medical Sciences, Fasa, Iran. The goal of this registry was to define overall baseline clinical characteristics and natural history of hospitalized patients with systolic HF, to evaluate current management schema and implementation of practice guidelines, and to determine the correlation between genetic predisposition environmental effects, individuals' characteristics of health, lifestyle, morbidity, and mortality in relation with the effects of medication. Results: To date, 2378 individuals with a mean of age 67.08±13.07 years have been registered. Among which, 1381 (58.07%) patients were diagnosed with denovo HF. Most of the patients (60.1%) were male, and 8.9% had admissions during the past 30 days. The most common causes of HF were ischemic heart disease (86.5%) and hypertension (5.3%). Most patients had NYHA class one (44.3%) and three (20.4%). Overall, near 30% had diabetes and more than 38% had hyperlipidemia. Most individuals have been not a history of cigarette smoking (68.7%) or water-pipe smoking (96.9%). Also, 22.2% were current opium users, and 3.2% were previous opium users. Conclusion: The findings of this registry could make a realistic view of HF as a chronic disease with a burden. Therefore, policymakers can design programs and guidelines to prevent disease and better survival and quality of life.

Predictors of long-term mortality after catheter ablation of ventricular tachycardia in a contemporary cohort of patients with structural heart disease.

AIMS: Ablation of ventricular tachycardias (VTs) in patients with structural heart disease has been established in the past decades as an effective and safe treatment. However, the prognosis and long-term outcome remains poor. METHODS AND RESULTS: We investigated 309 patients with ischaemic cardiomyopathy (ICM) and non-ischaemic cardiomyopathy (NICM) (186 ICM, 123 NICM; 271 males; mean age 64.1 ± 12 years; ejection fraction 34 ± 13%) after ≥1 VT ablations over a mean follow-up period of 34 ± 28 months. Electrical storm was the indication for 224 patients (73%), whereas 86 patients (28%) underwent epicardial as well as endocardial ablation. During follow-up, 132 patients (43%) experienced VT recurrence and 97 (31%) died. Ischaemic cardiomyopathy and NICM patients showed comparable results, regarding procedural endpoints, complications, VT recurrence and survival. The Cox-regression analysis for all-cause mortality revealed that the presence of higher left ventricular end-diastolic volume (LVEDV; P < 0.001), male gender (P = 0.018), atrial fibrillation (AF; P < 0.001), chronic obstructive pulmonary disease (COPD; P = 0.001), antiarrhythmic drugs during the follow-up (P < 0.001), polymorphic VTs (P = 0.028), and periprocedural complications (P = 0.001) were independent predictors of mortality. CONCLUSION: Ischaemic cardiomyopathy and NICM patients undergoing VT ablation had comparable results regarding procedural endpoints, complications, VT recurrence and 3-year mortality. Higher LVEDV, male gender, COPD, AF, polymorphic VTs, use of antiarrhythmics, and periprocedural complications are strong and independent predictors for increased mortality. The PAINESD score accurately predicted the long-term outcome in our cohort.

Value of Cardiogoniometry in Diagnosis of Coronary Artery Disease in Patients with Suspected Stable Ischemic Heart Disease: A Systematic Review and Meta-Analysis.

Cardiogoniometry (CGM) has been proposed as a new diagnostic tool for coronary artery disease (CAD) in recent years. Although different studies have evaluated the diagnostic value of CGM in CAD diagnosis, no pooled analysis of its diagnostic accuracy has been performed so far. This study aimed to assess the value of CGM in diagnosing CAD in patients with suspected stable ischemic heart disease (SIHD).This was a systematic review and meta-analysis conducted on available literature until May 2018. Studies considered coronary angiography as the reference standard for CAD diagnosis and reported CGM diagnostic value parameters were included. No language and time restrictions for enrolling the studies were considered. Statistical analysis was performed using Meta-DiSc software.The findings of the 10 studies published in 9 articles were enrolled in the meta-analysis. Overall pooled sensitivity was 71.7% (69.1 to 74.1; Cochrane Q = 39.5; P < 0.00001; I2 = 77.3%), and pooled specificity was 78.8% (76.3 to 81.1; Cochrane Q = 37.39; P < 0.00001; I2 = 75.9%). Regarding Egger's regression test (P = 0.32), there was no published bias in the studies.It seems that CGM, as an easy-to-use and non-invasive modality, should be considered as a part of risk stratifying strategies for CAD in patients with SIHD, mainly in patients with contraindications for stress tests. However, further studies with a high quality of methodology are still needed to assess the diagnostic value of CGM for CAD in patients with suspected SIHD.

Atrial fibrillation: A review of modifiable risk factors and preventive strategies.

Atrial fibrillation (AF), as the most common cardiac arrhythmia worldwide, is associated with increased mortality and morbidity. Successful therapeutic strategies have been introduced so far, but they are associated with significant costs. Therefore, identification of modifiable risk factors of AF and the development of appropriate preventive strategies may play a substantial role in promoting community health and reducing health care system costs. Modifiable cardiovascular risk factors including obesity, hypertension, diabetes mellitus, obstructive sleep apnea, alcohol consumption, smoking, and sedentary lifestyles have been proposed as possible contributors to the development and progression of AF. In this review, we discuss the role of modifiable risk factors in the development and management of AF and the evidence for the underlying mechanism for each of the potential risk factor.

Prevention of sudden cardiac death by the implantable cardioverter-defibrillator.

Sudden cardiac death (SCD) is a leading cause of death. The advent of the implantable cardioverter­defibrillator (ICD) has revolutionized prevention of SCD in high­risk patients with underlying cardiac diseases. However, several challenges remain. Identification of patients at risk who should receive an ICD is suboptimal, and the sole criterion applied in clinical practice is a severely reduced left ventricular ejection fraction despite the fact that SCD occurs mostly in patients with preserved or mildly reduced ejection fraction. Additionally, the majority of patients that do receive the ICD will not benefit from the device at the end. Therefore, improved risk stratification approaches to guide selection of patients for ICD implantation are definitely needed. There are several novel features and developments in the field with the subcutaneous defibrillator being probably the most important one and having the potential to substantially influence clinical practice. The role of catheter ablation of ventricular tachycardia, and particularly the potential to abolish the need for ICD implantation at least in selected patient groups, should be further defined. Internists and general practitioners play a significant role in the management of ICD patients, from identification of candidates for ICD implantation to early detection and appropriate treatment of complications.

Is echocardiographic epicardial fat thickness increased in patients with coronary artery disease? A systematic review and meta-analysis.

BACKGROUND: The relation of epicardial fat thickness (EFT) to coronary artery disease (CAD) has recently been reported in multiple studies. Echocardiography is a safe and relatively inexpensive and accessible approach to assess regional EFT, which can be performed easily in many centers. OBJECTIVE: To determine the association between echocardiographic EFT and the presence or the absence of CAD. METHODS: This was a systematic review and meta-analysis conducted on literature available in electronic databases up to March 2018. The articles measuring EFT by echocardiography in the right ventricular (RV) free wall were included in the study. The quality of the enrolled items was assessed using the Methodological Index for Non-Randomized Studies (MINORS) checklist. The analyses were performed using the Comprehensive Meta-Analysis version 2 software. Cochran's Q test and I2 index were used to evaluate heterogeneity. RESULTS: This meta-analysis was performed on 13 studies involving 2,436 patients (1,622 with CAD, and 814 without CAD). The maximum EFT reported by echocardiography was 12.9±2.7 mm in the CAD group and 8.4±2.5 mm in the non-CAD group. The minimum EFT reported by echocardiography was 2.2±1.8 mm in the CAD group and 1.8±1.4 mm in the non-CAD group. The heterogeneity was found among the researched studies (I2=91.8%, p=0.000, Q-value=146.43, df [Q] =12) using the random effect model. The patients with CAD had a significantly higher echocardiographic EFT than those without CAD (SMD=1.03, 95% CI= 0.70-1.37, p=0.000). CONCLUSION: According to the findings of this meta-analysis, the echocardiographic EFT in the subjects with CAD was significantly higher than that of those without CAD. The measurement of echocardiographic EFT seems to be an acceptable strategy for risk stratification of heart diseases considering ease of use, cost-effectiveness and non-exposure characteristics, compared to other imaging interventions.

Effectiveness of Coenzyme Q10 on echocardiographic parameters of patients with Duchenne muscular dystrophy.

BACKGROUND: Myocardial damage is a common complication in patients with Duchenne muscular dystrophy (DMD) that occurs due to myocardial replacement by fat and fibrosis. In recent years, efforts have been made toward finding new pharmacological agents with fewer complications which can be used as prophylactic before the symptoms. Coenzyme Q10 plays a central role in production of bioenergy in heart muscle and antioxidant in reperfusion condition of myocardial damaged muscle and leads to membrane stability and prevents cell death. OBJECTIVE: This study aimed at comparing the Effectiveness of coenzyme Q10 on echocardiographic parameters of pediatric patients with Duchenne muscular dystrophy. METHODS: This randomized clinical trial study (RCT) was carried out on 25 pediatric patients with pre-diagnosed DMD who attended the Children's Medical Center (CMC), Tehran, Iran from February 2013 to 2015. The patients were randomly divided into two groups. Group-1; (n=12) was treated with coenzyme Q10 for six months and group-2 ;(n=13) received placebo for the same time. The primary aim was to compare the myocardial performance index (MPI), between the two groups at the end of six months. Data were analyzed by SPSS software (ver-16) and using T-Test. RESULTS: Twenty-five patients under study were divided into two groups of (Q10=12) and (placebo=13). Mean ages were 8.9±1.7 and 8.6±1.4 in Q10 and placebo groups (P=0.66). No significant difference was detected in MPI at all three views of mitral and tricuspid and septum respectively in two groups after the end of treatment (0.41±0.13, and 0.43±0.6; P=0.59), (0.45±0.12, and 0.46±0.1; P=0.05), and (0.45±0.06, and 0.45±0.1; P=0.31). CONCLUSION: According to the results obtained from this study, coenzyme Q10 had no significant effect on improving the performance of echocardiographic parameters in patients with DMD. TRIAL REGISTRATION: The trial is registered at the Iranian Clinical Trial Registry (IRCT.ir) with the IRCT identification number IRCT2015070223018N1. FUNDING: This research has been financially supported by the Research Council of Tehran University of Medical Sciences.

Assosiation of Epicardial and Pericardial Fat Thickness with Coronary Artery Disease.

INTRODUCTION: Visceral adipose tissue is a known important risk factor for coronary artery disease (CAD). While some studies have suggested relationship between epicardial fat thickness (EFT) and CAD, there are no adequate studies for pericardial fat thickness (PFT). The aim of this study was to determine the association of EFT and PFT with CAD. METHODS: This cross-sectional study was conducted on patients who were candidates for elective coronary artery angiography, referred to Emam Reza Hospital, Mashhad, Iran during Jan 2014-2016. Demographic and laboratory data were collected. Transthoracic echocardiography was performed to determine average EFT and PFT at the standard parasternal long-axis view at end-systole for 3 cardiac cycles. SCA was performed on the same day. The patients were divided into two groups: CAD (n=59) and non-CAD (n=41) based on presence or absence of epicardial coronary artery stenosis of > 50%. Chi-square, independent T-test, and receiver operating characteristic (ROC) curve were used by SPSS Version 16 for data analysis. RESULTS: One hundred patients (44 women and 56 men) with an average age of 56.4 ± 9.9 years were studied. The two groups were not significantly different in demographic profile and cronary risk factors. While PFT was not significantly different between the two groups, EFT was significantly higher in CAD group (3.0 ± 3.69 vs. 1.2 ± 3.6, p <0.0001). Moreover, with the increase of the affected coronary arteries, EFT increased (p <0.0001). Gensini score had a strong correlation with amount of EFT (r = 0.765, p <0.0001). EFT with a cutoff value of 4.25 mm (sensitivity=79%, specificity=68%) was specified in predicting CAD. CONCLUSION: EFT measured by echocardiography can be used as an independent marker to predict CAD. More studies are needed to determine the predictive role of PFT for CAD.

Clinicopathological comparisons of open vein harvesting and endoscopic vein harvesting in coronary artery bypass grafting patients in Mashhad.

INTRODUCTION: Harvesting of the greater saphenous vein is almost an inevitable part of coronary artery bypass grafting (CABG) operations, and it is done by two main techniques, i.e., conventional or open vein harvesting (OVH) and the minimally-invasive endoscopic vein harvesting (EVH). This study aimed to compare these two techniques in off-pump CABG procedures with respect to clinical and pathological outcomes. METHODS: This cohort study was conducted on CABG candidates during a one-year period from October 2013 through September 2014 in the Department of Cardiac Surgery at Mashhad University of Medical Sciences. Eighty-seven patients voluntarily underwent EVH, and another 86 patients matched for age, gender, and other cardiovascular risk factors were selected for OVH. They were followed up for six weeks, and the main outcome measures were infections of the wound, pain, duration of hospital stay, and the costs of hospitalization. Paired sample t-test, independent t-test, or their non-parametric equivalents and the chi-squared test were used by SPSS version 17.0 for data analysis. RESULTS: The mean duration of time for vein harvesting was shorter in the EVH group (p < 0.001), and the pain score was lower (p = 0.04). No infections occurred at the site of the wound. The length of hospital stay was not significantly different for the two groups (OVH versus EVH: 8.5 ± 3.3 versus 8.4 ± 3.2 days; p-value: 0.08). Hospitalization costs were significantly higher in the EVH group (OVH versus EVH: 5.8 ± 4.7 versus 7.3 ± 2.0 million Tomman; p-value: 0.008), yet no difference was diagnosed with respect to endothelial damage in the vein grafts harvested by the EVH and OVH techniques. CONCLUSION: EVH is considered as a minimally invasive and safe vein harvesting technique in our Center, and it can reduce the harvesting time and post-operative pain. In addition, its efficiency was similar to that of OVH.

Comparison of Intravenous Morphine with Sublingual Buprenorphine in Management of Postoperative Pain after Closed Reduction Orthopedic Surgery.

BACKGROUND: Postoperative pain is a common side effect following surgery that can significantly reduce surgical quality and patient's satisfaction. Treatment options are morphine and buprenorphine. We aimed to compare the efficacy of a single dose of intravenous morphine with sublingual buprenorphine in postoperative pain control following closed reduction surgery. METHODS: This triple blind clinical trial was conducted on 90 patients referred for closed reduction orthopedic surgery. They were older than 18 years and in classes I and II of the American Society of Anesthesiologists (ASA) with an operation time of 30-90 minutes. Patients were divided into two groups of buprenorphine (4.5µg/kg sublingually) and morphine (0.2mg/kg intravenously). Baseline characteristics, vital signs, pain score, level of sedation and pharmacological side effects were recorded in the recovery room (at 0 and 30 minutes), and in the ward (at 3, 6 and 12 hours). SPSS version 19 software was used for data analysis and the significance level was set at P<0.05. RESULTS: Ninety patients were studied, 60 males and 30 females with a mean age of 37.7±16.2 years. There was no significant difference between the two groups in terms of baseline characteristics. Pain score in the morphine group was significantly higher than the buprenorphine group with an average score of 2.5 (P<0.001). Postoperative mean heart rate in the buprenorphine group was four beats lower than the morphine group (P<0.001). Also, in the buprenorphine 48.6% and in the morphine group 86.7% of cases were conscious in recovery (P=0.001) with a higher rate of pruritus in the latter group (P=0.001). CONCLUSION: Sublingual buprenorphine administration before anesthesia induction in closed reduction surgery can lead to better postoperative pain control in comparison to intravenous morphine. Due to simple usage and longer postoperative sedation, sublingual buprenorphine is recommended as a suitable drug in closed reduction surgery.

The correlation between end-tidal carbon dioxide and arterial blood gas parameters in patients evaluated for metabolic acid-base disorders.

BACKGROUND: The analysis of arterial blood gas (ABG) is an invasive procedure that is used frequently in the emergency department (ED) to evaluate the acid-base status of critically-ill patients. However, capnometry is an alternative procedure that has been used in recent years to determine the metabolic status of patients' blood. Considering the correlation between end-tidal carbon dioxide (ETCO2) and arterial partial pressure of carbon dioxide (PaCO2) identified in the previous studies and the strong correlation between PaCO2 and bicarbonate (HCO3(-) ), we assumed that ETCO2 might be a useful parameter in predicting the presence of metabolic acidosis. The aim of this study was to determine the correlation between ETCO2 and the parameters of ABG in adult patients who were likely present metabolic acid-base disturbances in the Emergency Department of Imam Reza Hospital, the largest academic hospital in Mashhad in northeast Iran. METHODS: This was a cross-sectional study conducted during six months on 62 adult patients who presented with suspected metabolic acid-base disorders to the ED. The exclusion criteria were patients with chronic obstructive pulmonary diseases, loss of consciousness, intubated patients, and those who were unable to tolerate capnography. The patients' demographic information and vital signs were recorded. Also, ABG and ETCO2 results were recorded. The Pearson product moment correlation analysis and linear regression were used to determine the correlation between ETCO2 and ABG parameters. RESULTS: Sixty-four patients were enrolled, consisting of 37 men and 27 women with a mean age of 55.4 ± 22.7 years. The most common complaints presented were nausea and vomiting (n = 24). The average value for ETCO2 was 26.2 ± 6.1. There were significant linear correlations between ETCO2 level, pH (r = 0.368), HCO3(-) (r = 0.869), PaCO2 (r = 0.795), and Base Excess (B.E.) (r = 0.346). HCO3 and PaCO2 were the significant predictor values for ETCO2 (linear regression analysis). CONCLUSION: ETCO2 can be an appropriate indicator to estimate HCO3(-) and PaCO2 in critical emergency situations, but it cannot be used as an indicator to estimate all ABG variables.