Effect of half-molar sodium lactate infusion on biochemical parameters in critically ill patients.

OBJECTIVE: To evaluate the impact of the infusion of sodium lactate 500ml upon different biochemical variables and intracranial pressure in patients admitted to the intensive care unit. DESIGN: A prospective experimental single cohort study was carried out. SCOPE: Polyvalent intensive care unit of a university hospital. PATIENTS: Critical patients with shock and intracranial hypertension. PROCEDURE: A 500ml sodium lactate bolus was infused in 15min. Plasma levels of sodium, potassium, magnesium, calcium, chloride, lactate, bicarbonate, PaCO2, pH, phosphate and albumin were recorded at 3 timepoints: T0 pre-infusion; T1 at 30min, and T2 at 60min post-infusion. Mean arterial pressure and intracranial pressure were measured at T0 and T2. RESULTS: Forty-one patients received sodium lactate: 19 as an osmotically active agent and 22 as a volume expander. Metabolic alkalosis was observed: T0 vs. T1 (p=0.007); T1 vs. T2 (p=0.003). Sodium increased at the 3 timepoints (T0 vs. T1, p<0.0001; T1 vs. T2, p=0.0001). In addition, sodium lactate decreased intracranial pressure (T0: 24.83±5.4 vs. T2: 15.06±5.8; p<0.001). Likewise, plasma lactate showed a biphasic effect, with a rapid decrease at T2 (p<0.0001), including in those with previous hyperlactatemia (p=0.002). CONCLUSIONS: The infusion of sodium lactate is associated to metabolic alkalosis, hypernatremia, reduced chloremia, and a biphasic change in plasma lactate levels. Moreover, a decrease in intracranial pressure was observed in patients with acute brain injury.

Update on metabolism and nutrition therapy in critically ill burn patients. / Metabolismo y terapia nutricional en el paciente quemado crítico: una revisión actualizada.

Major burn injury triggers severe oxidative stress, a systemic inflammatory response, and a persistent hypermetabolic and hypercatabolic state with secondary sarcopenia, multiorgan dysfunction, sepsis and an increased mortality risk. Calorie deficit, negative protein balance and antioxidant micronutrient deficiency after thermal injury have been associated to poor clinical outcomes. In this context, personalized nutrition therapy with early enteral feeding from the start of resuscitation are indicated. Over the last four decades, different nutritional and pharmacological interventions aimed at modulating the immune and metabolic responses have been evaluated. These strategies have been shown to be able to minimize acute malnutrition, as well as modulate the immunoinflammatory response, and improve relevant clinical outcomes in this patient population. The purpose of this updating review is to summarize the most current evidence on metabolic response and nutrition therapy in critically ill burn patients.

[Half-molar sodium-lactate: The osmotic agent we are looking for?]. / Lactato de sodio 0,5 molar: ¿el agente osmótico que buscamos?

Intracranial hypertension (ICH) is the most important modifiable factor with predictive negative value in brain injury patients. Osmotherapy is the most important first level specific measure in the treatment of ICH. Mannitol 20%, and 3, 7.5, 10, and 23% hypertonic sodium chloride are the most commonly used osmotic agents in the neurocritical care setting. Currently, controversy about the best osmotic agent remains elusive. Therefore, over the past few years, half-molar sodium lactate has been introduced as a new osmotic agent to be administered in the critically ill. Lactate is able to prevent hyperchloremia, as well as its adverse effects such as hyperchloremic acidosis, systemic inflammation, and acute kidney injury. Furthermore, lactate may also be used by glia as energy substrate in brain injury patients. Half-molar sodium lactate would also have a more potent and long-lasting effect decreasing intracellular osmolarity and by inhibiting neuronal volume control mechanisms. Pioneering researches in patients with traumatic brain injury have shown a more significant effect than mannitol on the control of ICH. In addition, in this group of patients this solution appears to be beneficial in preventing episodes of ICH. However, future research is necessary to corroborate or not these promising results.

[Fish oil containing lipid emulsions in critically ill patients: Critical analysis and future perspectives]. / Emulsiones lipídicas con aceite de pescado en el paciente crítico: análisis crítico y perspectivas futuras.

Third-generation lipid emulsions (LE) are soybean oil sparing strategies with immunomodulatory and antiinflammatory effects. Current evidence supporting the use of intravenous (i.v) fish oil (FO) LE in critically ill patients requiring parenteral nutrition or receiving enteral nutrition (pharmaconutrient strategy) mainly derives from small phase ii clinical trials in heterogenous intensive care unit patient's population. Over the last three years, there have been published different systematic reviews and meta-analyses evaluating the effects of FO containing LE in the critically ill. Recently, it has been demonstrated that i.v FO based LE may be able to significantly reduce the incidence of infections as well as mechanical ventilation days and hospital length of stay. Nonetheless, more robust evidence is required before giving a definitive recommendation. Finally, we strongly believe that a dosing study is required before new phase iii clinical trials comparing i.v FO containing emulsions versus other soybean oil strategies can be conducted.

Hyponatremia in the neurocritical care patient: An approach based on current evidence.

In the neurocritical care setting, hyponatremia is the commonest electrolyte disorder, which is associated with significant morbimortality. Cerebral salt wasting and syndrome of inappropriate antidiuretic hormone have been classically described as the 2 most frequent entities responsible of hyponatremia in neurocritical care patients. Nevertheless, to distinguish between both syndromes is usually difficult and useless as volume status is difficult to be determined, underlying pathophysiological mechanisms are still not fully understood, fluid restriction is usually contraindicated in these patients, and the first option in the therapeutic strategy is always the same: 3% hypertonic saline solution. Therefore, we definitively agree with the current concept of "cerebral salt wasting", which means that whatever is the etiology of hyponatremia, initially in neurocritical care patients the treatment will be the same: hypertonic saline solution.

[Pharmaconutrition with parenteral selenium in sepsis]. / Farmaconutrición parenteral con selenio en la sepsis.

Critical illness is characterized by oxidative stress which leads to multiple organ failure, and sepsis-related organ dysfunction remains the most common cause of death in the intensive care unit. Over the last 2 decades, different antioxidant therapies have been developed to improve outcomes in septic patients. According to recent evidence, selenium therapy should be considered the cornerstone of the antioxidant strategies. Selenium given as selenious acid or sodium selenite should be considered as a drug or pharmaconutrient with prooxidant and cytotoxic effects when a loading dose in intravenous bolus form is administered, particularly in the early stage of severe sepsis/septic shock. To date, several phase ii trials have demonstrated that selenium therapy may be able to decrease mortality, improve organ dysfunction and reduce infections in critically ill septic patients. The effect of selenium therapy in sepsis syndrome must be confirmed by large, well designed phase iii clinical trials. The purpose of this review is to discuss current evidence on selenium pharmaconutrition in sepsis syndrome.

[Tumor lysis syndrome in intensive therapy: diagnostic and therapeutic encare]. / Síndrome de lisis tumoral en terapia intensiva: encare diagnóstico y terapéutico.

The tumor lysis syndrome (TLS) is a life-threatening complication caused by the massive release of nucleic acids, potassium and phosphate into the blood. This complication is the result of tumor cell lysis, which may occur due to treatment of drug sensitive and is characterized by rapid capacity of proliferation, that is often hematological origin. Moreover, the TLS can be observed before starting the treatment due to spontaneous tumor cell death, and frequently worsens when chemotherapy is initiated. TLS has high mortality, so that its prevention continues to be the most important therapeutic measure. In the intensive care unit (ICU), physicians should be aware of the clinical characteristics of TLS, which results in severe electrolyte metabolism disorders, especially hyperkalemia, hyperphosphatemia and hypocalcemia, and acute kidney injury which is a major cause of ICU mortality. An adequate strategy for the management of the TLS, combining hydration, urate oxidase, and an early admission to ICU can control this complication in most patients. The aim of this review is to provide diagnostic tools that allow to the ICU physician to recognize the population at high risk for developing the TLS, and outline a proper strategy for treating and preventing this serious complication.

[Stress hyperglycemia and its control with insulin in critically ill patients: current evidence]. / Hiperglucemia de estrés y su control con insulina en el paciente crítico: evidencia actual.

OBJECTIVE: To analyze the current evidence on glycemic control with insulin therapy in the critically ill. RECENT FINDINGS: Stress hyperglycemia in critically ill patients has been associated with increased morbidity and mortality. Furthermore, current evidence suggests that glucose variability has a predictive value for hospital mortality. Initially, the Leuven studies showed that intensive insulin therapy was capable of reducing the mortality among surgical and medical ICU patients. Nevertheless, this strategy significantly increases the incidence of severe hypoglycemia. Three important trials on glucose control have been published recently: the VISEP, the Glucontrol study and the NICE-SUGAR. They have shown that strict control of glycemia is associated with a higher incidence of mortality and severe hypoglycemia. Furthermore, according to a recent meta-analysis, intensive insulin therapy may be beneficial for patients admitted to a surgical ICU. Further studies should be able to address some queries about these results on glycemic control in the critically ill.

[Selenium supplementation in critically ill patients: pharmacological issues and current evidence]. / Suplementación con selenio en el paciente crítico: aspectos farmacológicos y evidencia actual.

High dose intravenous selenium may be associated with a significant reduction in mortality among critically ill patients with systemic inflammation. Currently, parenteral selenium as sodium selenite seems to be a cornerstone of the antioxidant defence in the critically ill. So far, several clinical trials have evaluated the effects of selenium in monotherapy or as part of a multi-micronutrient approach, on relevant clinical end points for critically ill patients. Nonetheless, the results from these studies have sometimes been contradictory. We now have a better understanding of the pharmacokinetics of the initial and transient pro-oxidant effect of an intravenous bolus followed by the antioxidant effect of continuous infusion, which seems efficacious and safe among critically ill patients. Clinical confirmation of the potentially advantageous synergism between selenium and glutamine may soon be forthcoming but the most appropriate and the optimum time of supplementation remains undetermined. Short-term intravenous selenite (bolus injection plus continuous infusion) has shown to be safe and capable of optimizing serum selenium and antioxidant selenoenzymes activities. However, additional dose-ranging trials are necessary to elucidate an optimal and safe posology with confirmed pharmacokinetic profiles before more definitive phase III trials can be conducted.