Hypomagnesemia in critically ill cancer patients: a prospective study of predictive factors

Hypomagnesemia is the most common electrolyte disturbance seen upon admission to the intensive care unit (ICU). Reliable predictors of its occurrence are not described. The objective of this prospective study was to determine factors predictive of hypomagnesemia upon admission to the ICU. In a single tertiary cancer center, 226 patients with different diagnoses upon entering were studied. Hypomagnesemia was defined by serum levels <1.5 mg/dl. Demographic data, type of cancer, cause of admission, previous history of arrhythmia, cardiovascular disease, renal failure, drug administration (particularly diuretics, antiarrhythmics, chemotherapy and platinum compounds), previous nutrition intake and presence of hypovolemia were recorded for each patient. Blood was collected for determination of serum magnesium, potassium, sodium, calcium, phosphorus, blood urea nitrogen and creatinine levels. Upon admission, 103 (45.6 percent) patients had hypomagnesemia and 123 (54.4 percent) had normomagnesemia. A normal dietary habit prior to ICU admission was associated with normal Mg levels (P = 0.007) and higher average levels of serum Mg (P = 0.002). Postoperative patients (N = 182) had lower levels of serum Mg (0.60 ± 0.14 mmol/l compared with 0.66 ± 0.17 mmol/l, P = 0.006). A stepwise multiple linear regression disclosed that only normal dietary habits (OR = 0.45; CI = 0.26-0.79) and the fact of being a postoperative patient (OR = 2.42; CI = 1.17-4.98) were significantly correlated with serum Mg levels (overall model probability = 0.001). These findings should be used to identify patients at risk for such disturbance, even in other critically ill populations

Derrame pleural tuberculoso: avaliacao clinica e laboratorial / Tuberculous pleural effusion: clinical and laboratory evaluation

Sao apresentados os resultados do estudo de 44 pacientes com diagnostico de derrame pleural tuberculoso. A idade media foi 35 anos. Houve predominio do sexo masculino e da raca branca. As queixas principais foram febre (41/44), dor toracica (41/44) e emagrecimento (34/44), com tempo medio de duracao de sintomas de seis semanas. Em 21 pacientes o derrame foi localizado do lado direito, em 23 no lado esquerdo e em um paciente em ambos os lados. Em 23 por cento dos pacientes foi observado acometimento do parenquima pulmonar ipsilateral. Destes, tres apresentavam cultura de escarro positiva. Foram realizadas 49 biopsias de pleura em 44 pacientes. A primeira biopsia foi diagnostica em 82,5 por cento dos pacientes. A cultura do fragmento de pleura foi positiva em 75,8 por cento e a cultura do liquido pleural em 22,5 por cento. O liquido pleural era um exsudato com uma relacao liquido pleural/sangue maior que 0,5 para proteinas e maior que 0,6 para DHL em todos os casos. O estudo citologico mostrou predominio de linfocitos e escassez de celulas mesoteliais. Os pacientes receberam esquema terapeutico adequado, apresentando boa evolucao. Houve apenas uma falha. Os pacientes apresentaram melhora significativa (p < 0,05) com relacao ao peso, hemoglobina e diminuicao de VHS. Dos 44 pacientes, 23 evoluriam...