Early application of continuous high-volume haemofiltration can reduce sepsis and improve the prognosis of patients with severe burns

Background

In the early stage of severe burn, patients often exhibit a high level of inflammatory mediators in blood and are likely to develop sepsis. High-volume haemofiltration (HVHF) can eliminate these inflammatory mediators. We hypothesised that early application of HVHF may be beneficial in reducing sepsis and improving the prognosis of patients with severe burns.

Methods

Adults patients with burns ≥ 50% total burn surface area (TBSA) and in whom the sum of deep partial and full-thickness burn areas was ≥ 30% were enrolled in this randomised prospective study, and they were divided into control (41 cases) and HVHF (41 cases) groups. Patients in the control group received standard management for major burns, whereas the HVHF group additionally received HVHF treatment (65 ml/kg/h for 3 consecutive days) within 3 days after burn. The incidence of sepsis and mortality, some laboratory data, levels of inflammatory cytokines in the blood, HLA-DR expression on CD14⁺ peripheral blood monocytes, the proportion of CD25⁺Foxp3⁺ in CD4⁺ T lymphocytes, and the counts of CD3⁺, CD4⁺ and CD8⁺ T lymphocytes were recorded within 28 days post-burn.

Results

The incidence of sepsis, septic shock and duration of vasopressor treatment were decreased significantly in the HVHF group. In addition, in the subgroup of patients with burns ≥ 80% TBSA, the 90-day mortality showed significant decreases in the HVHF group. The ratio of arterial oxygen partial pressure to the fraction of inspiration oxygen was improved after HVHF treatment. In the patients who received HVHF treatment, the blood levels of inflammatory cytokines, including tumour necrosis factor-α, interleukin (IL)-1β, IL-6 and IL-8, as well as the blood level of procalcitonin were found to be lower than in the control group. Moreover, higher HLA-DR expression on CD14⁺ monocytes and a lower proportion of CD25⁺Foxp3⁺ in CD4⁺ T lymphocytes were observed in the patients in the HVHF group.

Conclusions

Early application of HVHF benefits patients with severe burns, especially for those with a greater burn area (≥ 80% TBSA), decreasing the incidence of sepsis and mortality. This effect may be attributed to its early clearance of inflammatory mediators and the recovery of the patient’s immune status.

Trial registration

Chinese Clinical Trial Register, ChiCTR-TRC-12002616. Registered on 24 October 2012.

Electronic supplementary material

The online version of this article (10.1186/s13054-018-2095-9) contains supplementary material, which is available to authorized users.

Population pharmacokinetics and dose simulation of vancomycin in critically ill patients during high-volume haemofiltration

This study aimed to describe the population pharmacokinetics of vancomycin in critically ill patients with refractory septic shock undergoing continuous venovenous high-volume haemofiltration (HVHF) and to define appropriate dosing for these patients. This was a prospective pharmacokinetic study in the ICU of a university hospital. Eight blood samples were taken over one vancomycin dosing interval. Samples were analysed by a validated liquid chromatography-tandem mass spectrometry assay. Non-linear mixed-effects modelling was used to describe the population pharmacokinetics. Dosing simulations were used to define therapeutic vancomycin doses for different HVHF settings. Nine patients were included (five male). The mean weight and SOFA score were 70 kg and 11, respectively. Mean HVHF settings were: blood flow rate, 240 mL/min; and haemofiltration exchange rate, 100 mL/kg/h. A linear two-compartment model with zero-order input adequately described the data. Mean parameter estimates were: clearance, 2.9 L/h; volume of distribution of central compartment (V(1)), 11.8L; volume of distribution of peripheral compartment (V(2)), 18.0 L; and intercompartmental clearance, 9.3 L/h. HVHF intensity was strongly associated with vancomycin clearance (P < 0.05) and was a covariate in the final model. Simulations indicate that after a loading dose, vancomycin doses required for different HVHF intensities would be 750 mg every 12h (q12h) for 69 mL/kg/h, 1000 mg q12h for 100 mL/kg/h and 1500 mg q12h for 123 mL/kg/h. Continuous infusion would also be a valuable administration strategy. In conclusion, variable and much higher than standard vancomycin doses are required to achieve therapeutic concentrations during different HVHF settings.