Euroscore). Presence of cardiovascular risk factors,chronic or paroxysmal atrial fibrillation, ischemic cardiopathology, depressed ejection fraction, previous renal insufficiency. Statistics used: mean, typical deviation. Analysis of qualitative variables by chi square, quantitative variables analysed according to the Student T test. Multivariable analysis by logistical regression Results:243 patients were studied. Mean age 67.5 ± 12 years. Mean Charlson Index 4.5 ± 2, APACHE II 15.3 ± 6.5, Euroscore 9.05. Hospital Mortality 14.4%. The sample studied is divided into two groups according to the presence of previous atrial fibrillation, 30.5%. In the single variable analysis the following factors were linked significantly, P< 0,05, to the presence of pre-operative atrial fibrillation: advanced age > 65 years old, 36%, female, 42%, and those having had double prosthetic valve surgery, 64%. In multi-variable analysis the following factors were linked independently to the higher prevalence of atrial fibrillation, female gender, OR 10.7 (CI 95%, 2.29-48), and the need for a double valve replacement OR 7.3 (CI 95%, 1-12,7). There was no link found between mortality and previous atrial fibrillation, but greater postoperative morbidity with an increase in the rate of postoperative atrial fibrillation, 66.2%, which was linked significantly, P < 0.005, pleural effusion, 52%, and prolonged stay 51% (significant difference P< 0,05). Conclusions: previous atrial fibrillation does not seem to reduce survival rates, but it does cause as greater postoperative morbidity Learning Objectives: Histamine plays an important role in the development of anaphylaxis. However, elevated plasma levels of histamine have not been observed in the majority of anaphylaxis.The aim of our study was to investigate the correlation between the levels of intracellular histamine and clinical symptoms in anaphylaxis. Methods: We collected blood samples of patients with anaphylaxis who were admitted to our ICU. In addition to clinical characteristics, routine blood analysis including C-reactive protein (CRP), treatments, outcomes, and levels of intracellular histamine were evaluated. The levels of intracellular histamine were defined as the difference between the levels of histamine in whole blood and in plasma. We used high-performance liquid chromatography (HPLC) to analyze histamine levels. Results:Consecutive 16 patients (12 males and 4 females) with anaphylaxis admitted to our ICU were enrolled. Mean age was 54.7 ± 18.3 years. Clinical characteristics included hypoxemia (n=8), shock (n=15), decrease levels of CNS (n=10) and severe abdominal impairment (n=5). No patient has died. The levels of intracellular histamine were inversely correlated with the severity of shock (p=0.044), decrease levels of CNS (p=0.0056) and abdominal impairment (p=0.0038), whereas histamine levels in plasma varied widely. Higher CRP levels were also correlated significantly with abdominal impairment (p=0.046). Conclusions: The decrease of intracellular histamine is correlated...
