How valuable is P-wave dispersion in the determination of carboxyhemoglobin levels?

Abstract

<jats:sec><jats:title>Objective:</jats:title><jats:p> To determine whether or not wave/interval dispersions in electrocardiography (ECG) are increased, and to define whether wave and interval dispersions are correlated with carboxyhemoglobin (COHb) levels. </jats:p></jats:sec><jats:sec><jats:title>Methods:</jats:title><jats:p> ECG, complete blood count, and biochemical parameters were taken from 87 patients with carbon monoxide (CO) poisoning as well as 90 control patients with similar age, gender, and body mass index distribution. COHb levels were recorded in CO-poisoning patients. The COHb levels and the relationships with ECG parameters were studied. </jats:p></jats:sec><jats:sec><jats:title>Results:</jats:title><jats:p> P<jats:sub>max</jats:sub>, P<jats:sub>min</jats:sub>, P<jats:sub>d</jats:sub>, PR<jats:sub>max</jats:sub>, PR<jats:sub>min</jats:sub>, PR<jats:sub>d</jats:sub>, QT<jats:sub>max</jats:sub>, QT<jats:sub>min</jats:sub>, QT<jats:sub>d</jats:sub>, cQT<jats:sub>max</jats:sub>, cQT<jats:sub>min</jats:sub>, cQT<jats:sub>d</jats:sub>, T<jats:sub>max</jats:sub>, T<jats:sub>min</jats:sub>, and T<jats:sub>d</jats:sub> in ECG were higher in intoxicated patients than the control group ( p &lt; 0.05 for all). Pearson’s correlation analyses showed moderately significant positive correlations between COHb level and P<jats:sub>max</jats:sub> ( r = 0.224; p = 0.037) and P<jats:sub>d</jats:sub> ( r = 0.222; p = 0.039). The receiver–operator characteristic (ROC) curve showed that a P<jats:sub>d</jats:sub> value of 38 ms determined by ECG separates patients with a COHb ≥ 20% with area under the ROC curve of 0.78 (95%CI = 0.71–0.83), a sensitivity of 67.9% (95%CI = 59.4–75.6), a specificity of 95% (95%CI = 83.0–99.2], a positive predictive value of 97.9% (95%CI = 92.5–99.7), and a negative predictive value of 46.3% (95%CI = 35.3–57.7.) </jats:p></jats:sec><jats:sec><jats:title>Conclusion:</jats:title><jats:p> A significant increase in wave/interval dispersions in the ECG of CO-poisoning patients compared with controls may show that not only a part is affected but both atrium and the ventricles as a whole are affected by hypoxic ischemia. When COHb levels of the patients are unavailable, P dispersion on ECG may show CO poisoning level of the patient. </jats:p></jats:sec>

Evaluation of the Citalopram levels on QTc Interval in Rats using with Radio-telemetry

“…Bazett's equation is used for correction of prolongation of QT (23)(24)(25). Corrected QT interval (QTc) was to compare QT values according to heart rates and evaluate the risk of arrhythmia (26,27). Plasma citalopram levels were measured at the end of the first week of treatment in the omeprazole-added groups and end of the second week of treatment in the all treatment groups.…”