Osmotic demyelination as a complication of hyponatremia correction: a systematic review

ABSTRACT Background: Rapid correction of hyponatremia, especially when severe and chronic, can result in osmotic demyelination. The latest guideline for diagnosis and treatment of hyponatremia (2014) recommends a correction limit of 10 mEq/L/day. Our aim was to summarize published cases of osmotic demyelination to assess the adequacy of this recommendation. Method: Systematic review of case reports of osmotic demyelination. We included cases confirmed by imaging or pathology exam, in people over 18 years of age, published between 1997 and 2019, in English or Portuguese. Results: We evaluated 96 cases of osmotic demyelination, 58.3% female, with a mean age of 48.2 ± 12.9 years. Median admission serum sodium was 105 mEq/L and > 90% of patients had severe hyponatremia (<120 mEq/L). Reports of gastrointestinal tract disorders (38.5%), alcoholism (31.3%) and use of diuretics (27%) were common. Correction of hyponatremia was performed mainly with isotonic (46.9%) or hypertonic (33.7%) saline solution. Correction of associated hypokalemia occurred in 18.8%. In 66.6% of cases there was correction of natremia above 10 mEq/L on the first day of hospitalization; the rate was not reported in 22.9% and in only 10.4% was it less than 10 mEq/L/day. Conclusion: The development of osmotic demyelination was predominant in women under 50 years of age, with severe hyponatremia and rapid correction. In 10.4% of cases, there was demyelination even with correction <10 mEq/L/day. These data reinforce the need for conservative targets for high-risk patients, such as 4–6 mEq/L/day, not exceeding the limit of 8 mEq/L/day

Relationship between vitamin D status, glycemic control and cardiovascular risk factors in Brazilians with type 2 diabetes mellitus

Abstract Objectives Determine the prevalence and identify predictors of hypovitaminosis D in patients with type 2 diabetes mellitus (T2DM); 2) correlate vitamin D levels with variables indicative of glycemic control and cardiovascular risk. Research design and methods We conducted a cross-sectional study with consecutive patients treated at a University Hospital’s Endocrinology outpatient clinic located at 12°58′S latitude, between October 2012 and November 2013. Hypovitaminosis D was defined as 25-hydroxyvitamin D < 30 ng/mL (chemiluminescence). Results We evaluated 108 patients with mean duration of T2DM of 14.34 ± 8.05 years and HbA1c of 9.2 ± 2.1%. Mean age was 58.29 ± 10.34 years. Most were women (72.2%), non-white (89.8%) and had hypertension (75.9%) and dyslipidemia (76.8%). Mean BMI was 28.01 ± 4.64 kg/m2; 75.9% were overweight. The prevalence of hypovitaminosis D was 62%. In multiple logistic regression, independent predictors of hypovitaminosis D were female gender (OR 3.10, p = 0.02), dyslipidemia (OR 6.50, p < 0.01) and obesity (OR 2.55, p = 0.07). In multiple linear regression, only total cholesterol (β = −0.36, p < 0.01) and BMI (β = −0.21, p = 0.04) remained associated with levels of 25-hydroxyvitamin D. Conclusions Using currently recommended cutoffs, the prevalence of hypovitaminosis D in Brazilians with T2DM was as high as that of non-tropical regions. Female gender, dyslipidemia and obesity were predictors of hypovitaminosis D. Low levels of 25-hydroxyvitamin D were correlated with high cholesterol and BMI values. Future studies are needed to evaluate whether vitamin D replacement would improve these parameters and reduce hard cardiovascular outcomes

Avaliação hemodinâmica em paciente criticamente enfermo Hemodynamic assessment in the critically ill patient

Uma fração crescente das atividades clínicas dos nefrologistas é exercida nas unidades de terapia intensiva (UTIs). Ao avaliar pacientes com insuficiência renal aguda no contexto de choque circulatório, que também apresentam anasarca e/ou trocas gasosas ruins, o nefrologista precisa decidir entre duas condutas antagônicas: 1) remover volume através de diálise ou diureticoterapia para melhorar o quadro edematoso; 2) administrar volume para melhorar a hemodinâmica. Para minimizar a chance de decisões incorretas, é imperativo que o nefrologista conheça as ferramentas disponíveis para avaliação hemodinâmica invasiva e de estimativa de adequação da volemia no paciente com doença crítica. Neste artigo, fazemos uma breve revisão da fisiologia da regulação do volume do líquido extracelular e, em seguida, abordamos o diagnóstico de volemia, com base em critérios clínicos e hemodinâmicos.<br>A growing fraction of the clinical duties of Nephrologists is undertaken inside intensive care units. While assessing patients with acute renal failure in the context of circulatory collapse, which are also edematous and/or with impaired gas exchanges, the Nephrologist must decide between two opposing therapies: 1) remove volume with the aid of dialysis or diuretics to improve the edematous state; 2) volume expand to improve hemodynamics. To minimize the odds of making incorrect choices, the Nephrologist must be familiar with the tools available for determining the adequacy of volume status and for invasive hemodynamic monitoring in the critically ill patient. In this manuscript, we will briefly review the physiology of extra cellular fluid volume regulation and then tackle the issue of volume status assessment, based on clinical and hemodynamic criteria

Motivo de "escolha" de diálise peritoneal: exaustão de acesso vascular para hemodiálise? Reason for "choosing" peritoneal dialysis: exhaustion of vascular access for hemodialysis?

INTRODUÇÃO: Pouco se conhece sobre a evolução de pacientes que iniciam DP como única alternativa. OBJETIVOS: Descrever o perfil clínico-demográfico e a ocorrência de peritonite em uma amostra de pacientes convertidos de HD para DP por exaustão de acesso vascular. MÉTODOS: Revisão dos prontuários de todos os pacientes do programa de DP do HGRS. RESULTADOS: Foram estudados 22 pacientes com idade mediana de 47,9 anos, 54,5% de homens, 84,2% de negros ou mulatos, 68,2% procedentes do interior da Bahia. DP foi a modalidade inicial de TRS em apenas quatro pacientes. Os 18 pacientes restantes iniciaram TRS através de HD; neste grupo, predominou o início de HD de forma emergencial e através de cateter duplo-lúmen (CDL). Em uma mediana de 7,7 meses em HD, a maioria dos pacientes (64,7%) usou mais de quatro CDL. Em apenas 7/18 (39%) pacientes, a conversão de HD para DP foi feita por escolha do paciente; na maioria dos casos, 11/18 (61%), o motivo de conversão foi exaustão de acesso vascular para HD. Peritonite foi mais frequente nos pacientes que entraram em HD por exaustão de acesso vascular que no restante do grupo. CONCLUSÕES: O início de TRS de forma emergencial através de HD utilizando CDL pode levar a uma rápida exaustão de acesso vascular, deixando a DP como única alternativa viável. Este modo inadequado de "seleção" de pacientes para DP está associado a maiores chances de ocorrência de peritonite.<br>INTRODUCTION: Little is known about the prognosis of patients beginnig peritoneal dialysis (PD) as their last alternative. OBJECTIVES: To describe the clinical-demographic profile of patients switching from hemodialysis (HD) to PD, due to exhaustion of the HD vascular access, and the occurrence of peritonitis among them. METHODS: Review of the medical records of all patients in the PD program of the Hospital Roberto Santos in the city of Salvador, state of Bahia, Brazil. RESULTS: The study comprised 22 patients (median age, 47.9 years), 54.5% of whom were men, 84.2%, black or mulattoes, and 68.2% originated from the inner Bahia state. Peritoneal dialysis was the initial modality of renal substitutive therapy (RST) in only four of those patients. The remaining 18 patients began RST through HD, mainly on an emergency basis and by using double-lumen catheter (DLC). In a median of 7.7 months on HD, most patients (64.7%) used four or more DLCs. In only 7/18 (39%) patients, the switch from HD to PD was based on the patient';s choice; in most cases, 11/18 (61%), the reason for switching to PD was exhaustion of HD vascular access. Peritonitis was more frequent in patients switching to PD due to exhaustion of HD vascular access than in the rest of the group. CONCLUSIONS: Initiating RST on an emergency basis through HD and using DLC may lead to a fast exhaustion of vascular access, leaving PD as the only viable option. This inadequate mode of patient "selection" for PD is associated with a higher risk for peritonitis