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Abstract Patients with acute liver failure develop massive liver damage, which is progressive in nature and carries high mortality rate. These patients can only be saved by intensive therapies, including liver transplantation. Diagnosis of liver failure in children depends on the presence of the first hepatic insult within 8 weeks with prothrombin time (PT) ≥15-19.9 seconds (s) or international normalized ratio (INR) ≥1.5-1.9 not corrected by vitamin K in the presence of clinical hepatic encephalopathy, or PT ≥20 s or INR ≥2.0; regardless of the presence or absence of clinical hepatic encephalopathy. Acute liver failure is usually associated with hemodynamic derangements which contribute to multiorgan failure. ALF is characterized by hyperdynamic circulation with high CO, low MAP, and low SVR through increased nitric oxide production. Hypovolemia is also aggravated by poor oral intake of these patients and transudation of fluid into extracellular space. SIRS – an essential component of ALF – also plays an important role in the pathogenesis of systemic vasodilation. Hemodynamic monitoring is an essential part of the management of the ICU patient. It helps to detect hemodynamic alterations, diagnose their underlying causes and optimize oxygen delivery to the tissues. Furthermore, hemodynamic monitoring is necessary to evaluate the adequacy of therapeutic interventions such as volume expansion or vasoactive medications. At the bedside, hemodynamic stability and tissue perfusion are monitored by a combination of clinical examination, monitoring devices and laboratory results. Clinical examination should always be an initial step in the assessment of a critically ill patient ; however it may frequently result in inaccurate assessment of the hemodynamic status. Physical examination and vital signs alone are unreliable indicators of CO in critical illness that normalization of vital signs cannot serve as an end-point of resuscitation. Recent developments include the move from static to dynamic variables to assess conditions such as cardiac preload and fluid responsiveness and the transition to less-invasive or even noninvasive monitoring techniques, at least in the perioperative setting, one of those recent developed modalities is EC. Electrical cardiometry has been proposed as a safe, accurate and reproducible technique for hemodynamic measurement in adults, children and infants. It is an impedance-based monitoring device that provides real-time cardiovascular assessment. The changes in electrical bio impedance is related to aortic flow pattern, and more specifically, influenced by the alignment of red blood cells in the aorta. The pulsatile impedance waveform corresponds to the cardiac cycle. Moreover, the rate of impedance change is used in the calculation of hemodynamic measures, such as blood velocity, contractility, SV and CO. Electrical cardiometry is FDA approved. The accuracy and the clinical utility of EC have been validated against other measures of CO like direct Fick’s method, thermodilution, and transthoracic and transesophageal echocardiography in a wide spectrum of patient conditions and populations across all ages. In spite EC has been used to monitor hemodynamics in sepsis and structural heart diseases, it wasn‘t used in pediatrics with ALF. The aim of this study is to assess the hemodynamics of pediatric patients with acute liver failure and its relation to the outcome. According to the exclusion and inclusion criteria, 20 cases were finally included in the study and subdevided into two groups, alive group (n=13) and deceased group (n=7). Inclusion criteria: Patient age below 18 years. Biochemical and/or clinical evidence of severe liver dysfunction: hepatic-based coagulopathy, with a prothrombin time (PT) ≥20s or international normalized ratio (INR) ≥2., that is not corrected by parenteral vitamin K and/or hepatic encephalopathy (must be present if the PT is 15.0–19.9s or INR 1.5–1.9). Inserting venous central line. Exclusion criteria: Patients of acute liver failure and previously known to have any cardiac, renal or pulmonary disease (could affect hemodynamic status of the patient). Data were collected and entered into the computer using Statistical Package for Social Science (SPSS) program for statistical analysis (ver 25). Data were entered as numerical or categorical, as appropriate. o Data were described using minimum, maximum, mean, median and 25th - 75th percentile. Our results showed that: 1. Most of studied patients were males (65%). 2. The median age of the deceased group was higher than the survived group (d) There was no statistically significant difference of CVP and capillary refill time between survived and deceased groups. (e) Indexed cardiac output measured by EC was compared between survived and deceased group on admission, at mid duration of hospital stay, before discharge for survived patients and before death for the deceased group. A significant increase in ICO among deceased group was found before death (p=0.019). (f) Indexed systemic vascular resistance was found to be significantly lower in the deceased group before death than the survived group before discharge. In conclusion, we believe that EC is a useful objective modality that can accurately assess the hemodynamics in children with ALF and can at least be used hand in hand with the clinical assessment and laboratory investigations to assess hemodynamic status and tissue perfusion. Finally, we recommend that serial EC measurements can be used to predict the outcome of children with ALF. |