Digestive decontamination in burn patients: A systematic review of randomized clinical trials and observational studies.

OBJECTIVE: The objective of this systematic review is to assess the effect of selective digestive decontamination (SDD) or non-absorbable enteral antibiotics (EA) on mortality, the incidence of infection and its adverse effects in burn patients. MATERIAL AND METHODS: Systematic review of randomized clinical trials (RCT) or observational studies enrolling burn patients, and comparing SDD or EA prophylaxis with placebo or no treatment. The search includes Pubmed/Medline, EMBASE, WOS, Cochrane Library (1970-2015). Bibliographic references were also reviewed, as well as communications presented at conferences (2012-2015), without language restrictions. Two reviewers inspected each reference identified by the search independently; the risk of bias was assessed with the Cochrane Collaboration method for RCT and the Newcastle Ottawa Scale for observational studies. RESULTS: Five RCT and 5 observational studies were identified enrolling a total of 1680 patients. The overall methodological quality of the studies was poor. The pooled effect of RCT using EA was OR: 0.62 (95% CI: 0.20-1.94). The only RCT using SDD reported OR 0.20 (95% CI: 0.09-0.81). The incidence of Enterobacteriaceae bloodstream was lower in cases treated with SDD or EA. The incidence of pneumonia was only reduced in the studies using SDD. None of the studies reported an increase in antibiotic resistance but in one RCT SDD was associated to an increase in methicillin-resistant Staphylococcus aureus infections, that was controlled with enteral vancomycin. CONCLUSIONS: SDD and EA have shown a beneficial effect in burn patients. Both practices are safe. Higher quality RCTs should be conducted to properly assess the efficacy and safety of SDD in this population.

Selective Digestive Decontamination Attenuates Organ Dysfunction in Critically Ill Burn Patients.

OBJECTIVE: To evaluate whether selective decontamination of the digestive tract (SDD) attenuates organ dysfunction in critically ill burn patients. BACKGROUND: The effect of SDD on the development and progression of organ dysfunction, as an important determinant of mortality in burned patients, is still unknown. We asked whether organ dysfunction is mitigated by treatment with SDD. METHODS: Patients with burns >20% of total body surface or suspected inhalation injury from a randomized placebo-controlled trial were analyzed to determine the relationship between treatment received (placebo or SDD) and the severity of organ dysfunction as measured by the area under the curve of the Sequential Organ Failure Assessment (SOFA) score (and its individual components) from day 1 to day 7 of admission. RESULTS: One hundred seven patients (53 in the SDD group and 54 in the placebo group) were included. Survival was significantly higher in SDD-treated patients (48 of 53, 90.6%) than in placebo-treated patients (39 of 54, 72.2%, P = 0.013). Total (P < 0.01) and respiratory (P < 0.01), cardiovascular (P = 0.04) and hematological (not reaching statistical significance, P = 0.07) organ dysfunction was associated with mortality after adjusting for predicted mortality. In multivariate logistic regression, SDD treatment was independently associated with total (P < 0.01), respiratory (P = 0.02), and hematological (P < 0.01) dysfunction over the first week postinjury. CONCLUSIONS: The beneficial effect of SDD on mortality in critically ill burned patients is accompanied by a reduction in the degree of organ dysfunction. SDD seems to be a valuable therapeutic strategy to prevent organ dysfunction and, more specifically, respiratory and hematological dysfunction in severely ill burn patients.

Selective decontamination of the digestive tract: the mechanism of action is control of gut overgrowth.

PURPOSE: Gut overgrowth is the pathophysiological event in the critically ill requiring intensive care. In relation to the risk of developing a clinically important outcome, gut overgrowth is defined as ≥10(5) potential pathogens including 'abnormal' aerobic Gram-negative bacilli (AGNB), 'normal' bacteria and yeasts, per mL of digestive tract secretion. Surveillance samples of throat and gut are the only samples to detect overgrowth. Gut overgrowth is the crucial event which precedes both primary and secondary endogenous infection, and a risk factor for the development of de novo resistance. Selective decontamination of the digestive tract (SDD) is an antimicrobial prophylaxis designed to control overgrowth. METHODS: There have been 65 randomised controlled trials of SDD in 15,000 patients over 25 years and 11 meta-analyses, which are reviewed. RESULTS AND CONCLUSIONS: These trials demonstrate that the full SDD regimen using parenteral and enteral antimicrobials reduces lower airway infection by 72 %, blood stream infection by 37 %, and mortality by 29 %. Resistance is also controlled. Parenteral cefotaxime which reaches high salivary and biliary concentrations eradicates overgrowth of 'normal' bacteria such as Staphylococcus aureus in the throat. Enteral polyenes control 'normal' Candida species. Enteral polymyxin and tobramycin, eradicate, or prevent gut overgrowth of 'abnormal' AGNB. Enteral vancomycin controls overgrowth of 'abnormal' methicillin-resistant S. aureus. SDD controls overgrowth by achieving high antimicrobial concentrations effective against 'normal' and 'abnormal' potential pathogens rather than by selectivity.

Efficacy of corticosteroid therapy in patients with an acute exacerbation of chronic obstructive pulmonary disease receiving ventilatory support.

BACKGROUND: Randomized trials assessing the effect of systemic corticosteroids on chronic obstructive pulmonary disease (COPD) exacerbations excluded patients who were mechanically ventilated or admitted to the intensive care unit (ICU). Critically ill patients constitute a population of persons who are prone to develop complications that are potentially associated with the use of corticosteroids (eg, infections, hyperglycemia, ICU-acquired paresis) that could prolong the duration of mechanical ventilation and even increase mortality. METHODS: A double-blind placebo-controlled trial was conducted to evaluate the efficacy and safety of systemic corticosteroid treatment in patients with an exacerbation of COPD who were receiving ventilatory support (invasive or noninvasive mechanical ventilation). A total of 354 adult patients who were admitted to the ICUs of 8 hospitals in 4 countries from July 2005 through July 2009 were screened, and 83 were randomized to receive intravenous methylprednisolone (0.5 mg/kg every 6 hours for 72 hours, 0.5 mg/kg every 12 hours on days 4 through 6, and 0.5 mg/kg/d on days 7 through 10) or placebo. The main outcome measures were duration of mechanical ventilation, length of ICU stay, and need for intubation in patients treated with noninvasive mechanical ventilation. RESULTS: There were no significant differences between the groups in demographics, severity of illness, reasons for COPD exacerbation, gas exchange variables, and corticosteroid rescue treatment. Corticosteroid treatment was associated with a significant reduction in the median duration of mechanical ventilation (3 days vs 4 days; P = .04), a trend toward a shorter median length of ICU stay (6 days vs 7 days; P = .09), and significant reduction in the rate of NIV failure (0% vs 37%; P = .04). CONCLUSION: Systemic corticosteroid therapy in patients with COPD exacerbations requiring mechanical ventilation is associated with a significant increase in the success of noninvasive mechanical ventilation and a reduction in the duration of mechanical ventilation. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01281748.

Long-term use of selective decontamination of the digestive tract does not increase antibiotic resistance: a 5-year prospective cohort study.

PURPOSE: Despite the evidence, the use of selective decontamination of the digestive tract (SDD) remains controversial, largely because of concerns that it may promote the emergence of antibiotic-resistant strains. The purpose of this study was to evaluate the long-term incidence of carriage of antibiotic-resistant bacteria (ARB), its clinical impact on developing infections and to explore risk factors of acquiring resistance. METHODS: This study was conducted in one 18-bed medical-surgical intensive care unit (ICU). All consecutive patients admitted to the ICU who were expected to require tracheal intubation for longer than 48 h were given a 4-day course of intravenous cefotaxime, and enteral polymyxin E, tobramycin, amphotericin B in an oropharyngeal paste and digestive solution. Oropharyngeal and rectal swabs were obtained on admission and once a week. Diagnostic samples were obtained on clinical indication. RESULTS: During 5 years 1,588 patients were included in the study. The incidence density of ARB was stable: 18.91 carriers per 1,000 patient-days. The incidence of resistant Enterobacteriaceae was stable; the resistance of Pseudomonas aeruginosa to tobramycin, amikacin and ciprofloxacin was strongly reduced; there was an increase of P. aeruginosa resistant to ceftazidime and imipenem, associated with the increase in imipenem consumption; the incidence of other nonfermenter bacilli and oxacillin-resistant Staphylococcus aureus was close to zero. Ninety-seven patients developed 101 infections caused by ARB: 23 pneumonias, 20 bloodstream infections and 58 urinary tract infections. Abdominal surgery was the only risk factor associated with ARB acquisition [risk ratio 1.56 (1.10-2.19)]. CONCLUSIONS: Long-term use of SDD is not associated with an increase in acquisition of resistant flora.

Limb intracompartmental sepsis in burn patients associated with occult infection.

BACKGROUND: Intracompartmental sepsis (IS) is a rare complication in burn patients. IS presents in patients with inadequate perfusion of intracompartmental tissues with subsequent ischaemic necrosis and infection. Contributing factors include high-volume resuscitation, delayed escharotomies and previous bacteraemias. We describe the profile of a series of patients who developed IS in our Intensive Care Burn Unit (ICBU). METHODS: We carried out a retrospective chart review of patients admitted to an ICBU over a 5-year period. RESULTS: Seven patients of 659 admissions (1.0%) developed IS involving the extremities. Diagnosis was based on the identification of purulent drainage and local swelling associated with signs of sepsis of unknown origin. Total body surface area (TBSA) burned averaged 67.4% and full-thickness body surface area (FTBSA) burned averaged 48.4%. All patients were sedated and mechanically ventilated. The first 24-h fluid requirements averaged 6.0 ml kg(-1) per %TBSA burn (range 3.5-7.0 ml kg(-1)per %TBSA). Escharotomies were performed in five patients within the first 24h of admission. Median time of diagnosis of IS was 23 days from admission (range 11-45 days). Four patients developed bacteraemia caused by the same microorganism infecting the soft tissue. In five cases, the infecting microorganism had previously colonised the overlying burned skin. Three patients required amputation of the affected limb. CONCLUSION: IS is a devastating infectious complication which appears late after large burns. Predisposing factors include high-volume resuscitation, delayed escharotomies, colonisation of the overlying skin and previous bacteraemias. Earlier diagnosis and management are needed to attain a better outcome.

A model for predicting mortality among critically ill burn victims.

OBJECTIVE: To develop a model for predicting mortality among burn victims. METHODS: All casualties admitted to our intensive care burn unit (ICBU) with a diagnosis of thermal or inhalation injury were studied. Age, total and full-thickness body surface area (BSA) burned, presence of inhalation injury, gender, mechanism of injury, delay to ICBU admission and mechanical ventilation during the first 72 h were recorded. The 851 participants were randomly divided into derivation (671) and validation (180) sets. From univariate and multivariate logistic regression analyses a mortality predictive equation was derived. RESULTS: Mortality was 17.6%. In univariate analysis, all variables were significantly associated with mortality except mechanism of injury and delay to ICBU admission. In multivariate analysis, age, total and full-thickness BSA burned, female gender and early mechanical ventilation were independently associated with mortality. CONCLUSIONS: We propose a mortality predictive equation for burned victims. In this model, MV and not inhalation injury is a mortality risk factor.