Microcirculation improvement after short-term infusion of vasopressin in septic shock is dependent on noradrenaline

OBJECTIVES: To assess the impact of vasopressin on the microcirculation and to develop a predictive model to estimate the probability of microcirculatory recruitment in patients with septic shock. METHODS: This prospective interventional study included patients with septic shock receiving noradrenaline for less than 48 hours. We infused vasopressin at 0.04 U/min for one hour. Hemodynamic measurements, including sidestream dark-field imaging, were obtained immediately before vasopressin infusion, 1 hour after vasopressin infusion and 1 hour after vasopressin withdrawal. We defined patients with more than a 10% increase in total vascular density and perfused vascular density as responders. ClinicalTrials.gov: NCT02053675. RESULTS: Eighteen patients were included, and nine (50%) showed improved microcirculation after infusion of vasopressin. The noradrenaline dose was significantly reduced after vasopressin (p=0.001) and was higher both at baseline and during vasopressin infusion in the responders than in the non-responders. The strongest predictor for a favorable microcirculatory response was the dose of noradrenaline at baseline (OR=4.5; 95% CI: 1.2-17.0; p=0.027). For patients using a noradrenaline dose higher than 0.38 mcg/kg/min, the probability that microcirculatory perfusion would be improved with vasopressin was 53% (sensitivity 78%, specificity 77%). CONCLUSIONS: In patients with septic shock for no longer than 48 h, administration of vasopressin is likely to result in an improvement in microcirculation when the baseline noradrenaline dose is higher than 0.38 mcg/kg/min.

Diabetes mellitus e intolerância à glicose são subdiagnosticados nas unidades de terapia intensiva / Diabetes mellitus and impaired glucose tolerance are underdiagnosed in intensive care units

OBJETIVO: Avaliar a presença de diabetes mellitus e a intolerância à glicose em pacientes internados em unidades de terapia intensiva. MÉTODOS: Foram incluídos pacientes clínicos, em pós-operatório de cirurgias eletivas e de urgência, e excluídos aqueles com história de diabetes mellitus. Para o diagnóstico de alterações prévias da glicemia, utilizou-se a dosagem da hemoglobina glicada (HbA1c) na admissão do paciente, sendo classificado em normal (<5,7%), intolerante à glicose (5,7-6,4%) ou diabético (>6,4%). Durante os 3 primeiros dias da internação, foram avaliados o controle glicêmico e as complicações clínicas. A evolução para óbito foi acompanhada por 28 dias. Para as análises estatísticas, utilizaram-se testes do qui-quadrado, ANOVA, teste t de Student, Kruskall-Wallis ou Mann Whitney. RESULTADOS: Foram incluídos 30 pacientes, 53% do gênero feminino, idade de 53,4±19,7 anos e APACHE II de 13,6±6,6. A maioria dos pacientes foi admitida por sepse grave ou choque séptico, seguido por pós-operatório de cirurgias eletivas, oncológicas, politraumatismo e cirurgia de urgência. Ao classificar esses pacientes segundo a HbA1c, apesar da ausência prévia de história de diabetes mellitus, apenas 13,3% tinham HbA1c normal, 23,3% tinham níveis compatíveis com o diagnóstico de diabetes mellitus e 63,3% eram compatíveis com intolerância à glicose. Houve associação significativa entre o diagnóstico de diabetes mellitus ou intolerância a glicose e o uso de droga vasoativa (p=0,04). CONCLUSÃO: Foi encontrada alta prevalência de diabetes mellitus e intolerância à glicose, sem diagnóstico prévio, em pacientes internados em uma unidade de terapia intensiva geral.

OBJECTIVE: To evaluate the presence of diabetes mellitus and impaired glucose tolerance in intensive care unit inpatients. METHODS: The study included patients in post-surgical care for elective and emergency surgery and excluded those patients with known diabetes mellitus. To diagnose prior serum glucose level disorders, we considered the value of glycated hemoglobin (HbA1c) at the time of admission, classifying the patients as normal (<5.7%), glucose intolerant (5.7-6.4%) or diabetic (>6.4%). During the first 3 days of the patient's hospital stay, glycemic control and clinical complications were assessed. Mortality was monitored for 28 days. For the statistical analyses, chi-square, ANOVA, student's t, Kruskal-Wallis or Mann Whitney tests were used. RESULTS: Thirty patients were included in the present study, 53% of whom were women; the patients had a mean age of 53.4±19.7 years and an APACHE II score of 13.6±6.6. The majority of patients were admitted for severe sepsis or septic shock followed by post-operative care for elective surgery, oncological surgery, multiple traumas and emergency surgery. When classifying these patients according to HbA1c, despite the absence of a prior history of diabetes mellitus, only 13.3% had a normal HbA1c level, 23.3% had levels compatible with the diagnosis of diabetes mellitus and 63.3% had levels compatible with impaired glucose tolerance. We found a significant association between the diagnosis of diabetes mellitus or impaired glucose tolerance and the use of vasoactive drugs (p=0.04). CONCLUSION: A high prevalence of undiagnosed diabetes mellitus and impaired glucose tolerance was observed in inpatients at a general intensive care unit.

Comparison of lactate values obtained from different sites and their clinical significance in patients with severe sepsis / Comparação de valores de lactato obtidos em diferentes sítios e sua importância clínica em pacientes com sepse grave

CONTEXT AND OBJECTIVE: The ideal site for lactate collection has not been clearly established. This study aimed to evaluate associations between lactate levels in arterial blood (Lart), peripheral venous blood (Lper) and central venous blood (Lcen) in patients with severe sepsis or septic shock. DESIGN AND SETTING: Cross-sectional analytical study in an tertiary university hospital. METHOD: Samples from patients with a central venous catheter and from healthy volunteers (control group) were collected. Blood was drawn simultaneously for measurements of Lart, Lper and Lcen, and the first sample was collected less than 24 hours after the onset of organ dysfunction. The results were analyzed using Pearson correlation, Bland-Altman and McNemar tests. RESULTS: A total of 238 samples were collected from 32 patients. The correlation results were r = 0.79 (P < 0.0001) for Lart/Lper and r = 0.84 (P < 0.0001) for Lart/Lcen. Bland-Altman showed large limits of agreement: -3.2 ± 4.9 (-12.8 to 6.4) and -0.8 ± 5.9 (-12.5 to 10.8), for Lper and Lcen respectively. In the control group, there was greater correlation (r = 0.9009, P = 0.0004) and agreement: -0.7 ± 1.2 (-3.1 to 1.7). Regarding clinical intervention, there was good agreement between Lart/Lcen (96.3 percent; three disagreements), with worst results for Lart/Lper (87.0 percent) with 10 cases of disagreement (P = 0.04). In eight patients (80.0 percent) Lper was higher than Lart. CONCLUSION: Lcen, and not Lper, can replace Lart with good correlation and clinical agreement. Lper tends to overestimate Lart, thus leading to unnecessary therapeutic interventions.

CONTEXTO E OBJETIVO: O sítio ideal de coleta do lactato não está claramente estabelecido. Este estudo objetivou avaliar a associação dos valores de lactato do sangue arterial (Lart), venoso periférico (Lper) e venoso central (Lcen) em pacientes com sepse grave ou choque séptico. TIPO DE ESTUDO E LOCAL: Estudo transversal analítico em hospital universitário terciário. MÉTODOS: Amostras de pacientes com cateter venoso central e voluntários sadios (grupo controle) foram coletadas. O sangue foi obtido de forma simultânea para medida do Lart, Lper and Lcen, sendo a primeira amostra coletada no máximo 24 horas após o início da disfunção orgânica. Resultados foram analisados usando a correlação de Pearson, os testes de Bland-Altman e McNemar. RESULTADOS: Um total de 238 amostras foi coletado em 32 pacientes. Resultados da correlação: r = 0.79 (P < 0,0001) para Lart/Lper e r = 0.84 (P < 0,0001) para Lart/Lcen. Bland-Altman mostrou largos limites de concordância, -3.2 ± 4.9 (-12.8 to 6.4) and -0.8 ± 5.9 (-12.5 to 10.8), para Lper e Lcen, respectivamente. No grupo controle, houve uma maior correlação (r = 0.9009, P = 0,0004) e concordância: -0.7 ± 1.2 (-3.1 to 1.7). No que se refere à intervenção clínica, houve boa concordância Lart/Lcen (96.3 por cento, três não concordantes), com resultados piores encontrados para Lart/Lper (87.0 por cento) com 10 casos não concordantes (P = 0,04). Em oito pacientes (80.0 por cento) Lper foi mais elevado que Lart. CONCLUSÃO: Lcen, e não Lper, pode substituir Lart com boa correlação e concordância clínica. Lper tende a superestimar Lart, assim levando a intervenç ões terapêuticas desnecessárias.