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Background and purpose: According to the confirmed dangerous side effects of chemical preservatives such potassium sorbate in public health and food safety, accurate monitoring of the presence of preservatives in food is necessary. Since, according to Iran national standard, using potassium sorbate in dough as preservative is prohibited, so, this study aimed to investigate the presence of potassium sorbate in dough and validation method of potassium sorbate detection. Material and methods: In this study, 100 dough samples were collected from Mazandaran province factories. The samples were analyzed by high performance liquid chromatography (HPLC), UV detectors. Validation was performed according to USP and ICH guidelines. Results: The correlation coefficient of curve equation was 99.9%. The linearity rang was from 19 to 100 µg/ml and the limit of detection LOD and limit of quantification (LOQ) were 6.37 and 19.11 µg/ml, respectively. The accuracy of repeatability and intermediate precision of the range were acceptable. Potassium sorbate was detected in 32% samples. Content of Potassium sorbate in 22% of samples was greater than 100 mg/kg and in 10% of samples were lower than 100 mg/kg. Conclusion: With regard to the presence of potassium sorbate in dough samples despite of Iran national standard ban on the use of it in dough, continues monitoring of several preservatives such as potassium sorbate seems to be necessary.

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Background and purpose: In ischemic state some substrates are shifted to glucose leading to less oxygen consumption. The aim of this study was to assess the effect of glucose, insulin and potassium (GIK) infusion in patients with high risk acute coronary syndrome (ACS). Materials and methods: A double-blind, pilot clinical trial was conducted in 41 high-risk ACS-NSTEMI-patients attending Emergency Department in the first 12h of showing symptoms. They were randomly assigned to receive either GIK (n=20) or conventional treatment (n=21). We recorded the patients’ demographic information, serum troponin level and Electrocardiogram (ECG) findings in admission and 24 hours later, and 30-day mortality rate. Results: The mean age of patients was 61.46±12.13 years and there were 21 (51.2%) male. There was no significant difference between two groups in age, gender, history of underlying diseases and lab data (P>0.05). ECG changes showed improvements among 9 patients in GIK group (50%) and 7 patients in control group (33.3%) (P=0.55). The mean changes of troponin level in GIK and control groups were 1.01±2.03 and 1.87±4.40, respectively. The 30-day mortality rate was zero. Conclusion: This study showed no significant difference in efficacy of high dose GIK on ECG changes, serum troponin level and one-month mortality rate after treatment.

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Background and purpose: Nephrolithiasis in the pediatric population includes 7% of all kidney stone disorders in all age groups. Potassium citrate is one of medical agents used in treatment of these disorders. This study investigated the role of potassium citrate in treatment of patients with kidney stones without any metabolic or infectious risk factors.
Materials and methods: A clinical trial was conducted in all patients less than 16 years of age in whom ultrasonography confirmed kidney or urinary tract stones <7mm but had no metabolic or infectious risk factors. Patients were divided into two groups; group I (n=47) were treated with 1-2ml/kg potassium citrate daily and group II (n=33) who received no medication.
Results: A total of 149 patients with nephrolithiasis was assessed of whom 80 included in current study. Improvements in number of stones was seen in 29 (76%) patients in group I and 17 (57%) in group II (P=0.403). Improvements in maximum size of stones were found in 30 (79%) cases in group I and 22 (73%) patients in group II (P=0.791). Total burden of stones showed improvements in 82% of patients in group I and 73% of those in group II (P=0.887). There were no significant differences between the two groups in any of these items.
Conclusion: Potassium citrate can reduce the size and number of stones in most children with renal stones less than 7mm who have no underlying risk factor. But current study found non-pharmacological supportive treatments to yield similar results.
 

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Pregnancy at the site of cesarean section is an uncommon form of ectopic pregnancy which is associated with delayed diagnosis and late treatment may cause maternal mortality. This paper reports an ectopic pregnancy on the site of an earlier cesarean section. The patient is a 33-year-old woman with history of a normal delivery and a cesarean section and a uterine curettage in the past year who complained of unintentional uterine bleeding despite consistent use of combined contraceptive pills. Last menstrual period was 12 Sep 2017 and the patient reported abnormal uterine bleeding. In pregnancy tests, and after ultrasound for pregnancy, a uterine cavity without a pregnancy sack was observed. To make the final diagnosis, transvaginal ultrasonography was applied which proved ectopic pregnancy with fetal heartbeat at six weeks and two days. The patient was then referred to a clinic and pregnancy termination was started by injection of potassium chloride into the embryo and the mother received Methotrexate. The history of cesarean section and curettage can cause ectopic pregnancy. So, in the case of abnormal uterine bleeding, despite the use of contraceptive pills, pregnancy examinations should be done to avoid further complications. According to this study, administration of potassium chloride into the embryo and Methotrexate to the mother is an appropriate method in terminating ectopic pregnancy at the site of a previous cesarean section.
 

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Background and purpose: There are controversies on the association between electrolytes and Coronavirus disease 2019 (COVID-19) and its severity. Studies on these issues may help in resolving ambiguities. The purpose of this study was to assess the association between electrolyte indices and being infected with COVID-19 and developing severe symptoms using a meta-analysis.
Materials and methods: A thorough search was done in national and international electronic databases using Medical Subject Headings (MeSH) terms. Quality assessment was conducted by Newcastle-Ottawa scale (NOS) checklist. We estimated the standardized mean difference between electrolyte indices and the incident of COVID-19 infection and its severity.
Results: After screening the papers, 12 met the inclusion criteria. According to the meta-analysis results, the standardized mean differences for serum level of sodium and potassium between the dead and survived COVID-19 patients was estimated to be 0.22 (95% CI: -0.03, 0.46) and 0.14 (95% CI: -0.22, 0.50), respectively. The standardized mean differences for serum levels of sodium, calcium, and potassium between patients with severe and non-severe COVID-19 were estimated to be -0.28 (95% CI: -0.72, 0.17), -1.07(95% CI: -1.58, -0.55), and -0.10 (95% CI: -0.47, 0.27), respectively.
Conclusion: In this meta-analysis, the standardized mean difference for calcium was significantly lower in severe COVID-19 patients compared to that in patients with mild and moderate forms of the disease.

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Background and purpose: Patients admitted at the intensive care unit (ICU) need blood draws for chemistry analytes and arterial blood gas (ABG) analysis. Repeated blood drawing is one of the most common causes of anemia in these group of patients. Measurement of analytes only by ABG analyzer can be beneficial for preventing anemia. The aim of this study was to compare the biochemical analytes in venous and ABG samples in ICU patients.
Materials and methods: This cross-sectional study was performed in 223 patients hospitalized in the ICU. These patients undergoing ABG analysis and simultaneous venous sampling. The value of Ca, Na, K, Hct, and glucose were measured in venous samples with a laboratory auto-analyzer and in arterial samples with an ABG analyzer.
Results: The mean age of patients was 61.14±16.96 years. The mean difference between ABG and serum samples was 1.12 mEq/L for sodium, -0.29 mEq/L for potassium, -0.98 mg/dl for calcium, 0.33 mg/dl for glucose, and 4.39%% for hematocrit. In addition, 95% limit of agreement was -12.3 to 9 for sodium, -0.7 to 1.29 for potassium, -1.31 to 3.8 for calcium, -39.13 to 40.32 for glucose, and -13.5 to 8.5 for hematocrit.
Conclusion: Because of acceptable agreement for sodium, potassium, and hematocrit, ABG analyzer can be used in ICU patients and emergency situations. There is a remarkable bias between the ABG-measured and laboratory-measured calcium and glucose, so the calcium and glucose measurement by the ABG analyzer are not reliable.