Year in review in intensive care medicine, 2005. II. Infection and sepsis, ventilator-associated pneumonia, ethics, haematology and haemostasis, ICU organisation and scoring, brain injury

Genetic association between CD86 polymorphisms and the risk of sepsis in a Chinese Han population

BACKGROUND

Sepsis is a clinical syndrome that is frequently observed after injury or infection, representing a leading cause of mortality worldwide. CD86 (B7-2) is a co-stimulatory molecule on antigen-presenting cells, and plays critical roles in immune responses.

METHODS

A total of 135 sepsis patients and 151 healthy controls were recruited in the current case-control study. Hardy-Weinberg equilibrium (HWE) conformity was examined to assess the representativeness of the study population. CD86 gene polymorphisms were genotyped using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The relative expression of CD86 mRNA was estimated via quantitative real-time PCR (qRT-PCR). Chi-square test was performed to estimate the associations between CD86 gene polymorphisms and sepsis risk, and the results were presented through odds ratio (OR) and 95% confidence intervals (CI).

RESULTS

The genotype distributions of CD86 polymorphisms in the case and control groups conformed to HWE. The GA genotype of the polymorphism rs1129055 was significantly correlated with an increased risk of sepsis (OR = 2.540, 95%CI = 1.288-5.008). The TT genotype of rs1915087 was a risk factor for sepsis (OR = 2.769, 95%CI = 1.292-5.935). High linkage disequilibrium was observed between the two polymorphisms (D' = 1.0, r² = 0.955). However, no significant association was observed between CD86 polymorphisms and its gene expressions (P > 0.05 for all).

CONCLUSION

CD86 gene polymorphisms rs1129055 and rs1915087 may increase the risk of sepsis.

Astilbin alleviates sepsis-induced acute lung injury by inhibiting the expression of macrophage inhibitory factor in rats

Sepsis is a systemic inflammatory response syndrome caused by severe infections. Astilbin is a dihydroflavonol derivative found in many medicinal and food plants with multiple pharmacological functions. To investigate the effects of astilbin on sepsis-induced acute lung injury (ALI), cecal ligation and puncture was performed on rats to establish a sepsis-induced ALI model; these rats were then treated with astilbin at different concentrations. Lung injury scores, including lung wet/dry ratio, protein leakage, myeloperoxidase activity, and inflammatory cell infiltration were determined to evaluate the effects of astilbin on sepsis-induced ALI. We found that astilbin treatment significantly attenuates sepsis-induced lung injury and improves survival rate, lung injury scores, lung wet/dry ratio, protein leakage, myeloperoxidase activity, and inflammatory cell infiltration. Astilbin treatment also dramatically decreased the production of inflammatory cytokines and chemokines in bronchoalveolar lavage fluid. Further, astilbin treatment inhibited the expression and production of macrophage inhibitory factor (MIF), which inhibits the inflammatory response. Collectively, these data suggest that astilbin has a protective effect against sepsis-induced ALI by inhibiting MIF-mediated inflammatory responses. This study provides a molecular basis for astilbin as a new medical treatment for sepsis-induced ALI.

An intensive care approach to posterior reversible encephalopathy syndrome (PRES): An analysis of 7 cases

OBJECTIVE

The aim of this study was to retrospectively evaluate the intensive care unit treatments applied to obstetrics patients with a diagnosis of posterior reversible encephalopathy syndrome (PRES).

MATERIAL AND METHODS

The cases of 7 pregnant patients who had been diagnosed with PRES between July 2011 and July 2013 were retrospectively reviewed. The patients' clinical data, brain magnetic resonance imaging (MRI) images before and after treatment, and neuropsychological tests were evaluated.

RESULTS

Five out of 7 patients had eclampsia, 1 patient had severe preeclampsia, and 1 patient developed HELLP syndrome secondary to PRES. Calcium channel blockers and β-blockers were used as antihypertensive treatment. All patients were treated with parenteral magnesium sulfate. In addition, sodium thiopental was given to control sedation and convulsions in all patients except 1. The neurological and radiological findings of all cases treated in the intensive care unit improved.

CONCLUSION

Posterior reversible encephalopathy syndrome is a clinical condition with a multifactorial etiology and can result in different clinical findings. Radiological imaging techniques can be used for the diagnosis of PRES. Pregnancy and the postpartum period often lead to this syndrome. In some cases, PRES can cause irreversible neurological deficits or death. For patients with severe radiological findings, early diagnosis and thiopental infusion, in addition to treatment with antihypertensive agents and magnesium sulfate, may lead to quicker and more effective recovery from clinical manifestations. We suggest supplementation of standard treatment with early thiopental infusion.

Curcumin protects against sepsis-induced acute lung injury in rats

The present study aimed to investigate the effect of curcumin on sepsis-induced acute lung injury (ALI) in rats, and explore its possible mechanisms. Male Sprague-Dawley rats were randomly divided into the following five experimental groups (n = 20 per group): animals undergoing a sham cecal ligature puncture (CLP) (sham group); animals undergoing CLP (control group); or animals undergoing CLP and treated with vehicle (vehicle group), curcumin at 50 mg/kg (low-dose curcumin [L-Cur] group), or curcumin at 200 mg/kg (high-dose curcumin [H-Cur] group).At 6, 12, 24 h after CLP, blood, bronchoalveolar lavage fluid (BALF) and lung tissue were collected. The lung wet/dry weight (W/D) ratio, protein level, and the number of inflammatory cells in the BALF were determined. Optical microscopy was performed to examine the pathologic changes in lungs. Myeloperoxidase (MPO) activity, malondialdehyde (MDA) content, as well as superoxidase dismutase (SOD) activity were measured in lung tissues. The expression of inflammatory cytokines, tumor necrosis factor-alpha (TNF-α), interluekin-8 (IL-8), and macrophage migration inhibitory factor (MIF) were determined in the BALF. Survival rates were recorded at 72 h in the five groups in another experiment. Treatment with curcumin significantly attenuated the CLP-induced pulmonary edema and inflammation, as it significantly decreased lung W/D ratio, protein concentration, and the accumulation of the inflammatory cells in the BALF, as well as pulmonary MPO activity. This was supported by the histopathologic examination, which revealed marked attenuation of CLP-induced ALI in curcumin treated rats. In addition, curcumin significantly increased SOD activity with significant decrease in MDA content in the lung. Also, curcumin caused down-regulation of the inflammatory cytokines TNF-α, IL-8, and MIF levels in the lung. Importantly, curcumin improved the survival rate of rats by 40%-50% with CLP-induced ALI. Taken together, these results demonstrate the protective effects of curcumin against the CLP-induced ALI. This effect can be attributed to curcumin ability to counteract the inflammatory cells infiltration and, hence, ROS generation and regulate cytokine effects.

Incidence and clinical implication of nosocomial infections associated with implantable biomaterials - catheters, ventilator-associated pneumonia, urinary tract infections

Health care associated infections, the fourth leading cause of disease in industrialised countries, are a major health issue. One part of this condition is based on the increasing insertion and implantation of prosthetic medical devices, since presence of a foreign body significantly reduces the number of bacteria required to produce infection. The most significant hospital-acquired infections, based on frequency and potential severity, are those related to procedures e.g. surgical site infections and medical devices, including urinary tract infection in catheterized patients, pneumonia in patients intubated on a ventilator and bacteraemia related to intravascular catheter use. At least half of all cases of nosocomial infections are associated with medical devices.Modern medical and surgical practices have increasingly utilized implantable medical devices of various kinds. Such devices may be utilized only short-time or intermittently, for months, years or permanently. They improve the therapeutic outcome, save human lives and greatly enhance the quality of life of these patients. However, plastic devices are easily colonized with bacteria and fungi, able to be colonized by microorganisms at a rate of 0.5 cm per hour. A thick biofilm is formed within 24 hours on the entire surface of these plastic devices once inoculated even with a small initial number of bacteria.The aim of the present work is to review the current literature on causes, frequency and preventive measures against infections associated with intravascular devices, catheter-related urinary tract infection, ventilator-associated infection, and infections of other implantable medical devices. Raising awareness for infection associated with implanted medical devices, teaching and training skills of staff, and establishment of surveillance systems monitoring device-related infection seem to be the principal strategies used to achieve reduction and prevention of such infections. The intelligent use of suitable antiseptics in combination with medical devices may further support reduction and prevention of such infections. In addition to reducing the adverse clinical outcomes related with these infections, such reduction may substantially decrease the economic burden caused by device-related infection for health care systems.

Interleukin-17A plays a pivotal role in polymicrobial sepsis according to studies using IL-17A knockout mice

BACKGROUND

Interleukin (IL)-17A is a proinflammatory cytokine and plays an important role in neutrophil recruitment. We investigate the role of IL-17A in a mouse polymicrobial sepsis model.

MATERIALS AND METHODS

IL-17A knockout mice (KO) and wild-type (WT) mice were subjected the cecal ligation and puncture (CLP). Survival was assessed for the following 7 d after the CLP operation, and histopathologic findings were evaluated 12 h after CLP. Bacterial outgrowth in blood was assessed by blood culture 12 h after CLP. After CLP, expression of inflammatory mediators in serum was assessed by enzyme-linked immunosorbent assay (ELISA). Furthermore, expression of FOXP3 and IL-17A in the spleen was assessed by immunohistochemical staining and flow cytometry.

RESULTS

Mortality was increased in KO mice compared with WT mice after CLP. Furthermore, bacterial outgrowth in blood and serum high mobility group box 1 (HMGB1) levels were also significantly greater in KO mice than WT mice. The expression of FOXP3 in the spleen was significantly greater in KO mice than WT mice.

CONCLUSION

IL-17A play pivotal role in host defense during septic peritonitis.

Cost-consequence analysis of remifentanil-based analgo-sedation vs. conventional analgesia and sedation for patients on mechanical ventilation in the Netherlands

INTRODUCTION

Hospitals are increasingly forced to consider the economics of technology use. We estimated the incremental cost-consequences of remifentanil-based analgo-sedation (RS) vs. conventional analgesia and sedation (CS) in patients requiring mechanical ventilation (MV) in the intensive care unit (ICU), using a modelling approach.

METHODS

A Markov model was developed to describe patient flow in the ICU. The hourly probabilities to move from one state to another were derived from UltiSAFE, a Dutch clinical study involving ICU patients with an expected MV-time of two to three days requiring analgesia and sedation. Study medication was either: CS (morphine or fentanyl combined with propofol, midazolam or lorazepam) or: RS (remifentanil, combined with propofol when required). Study drug costs were derived from the trial, whereas all other ICU costs were estimated separately in a Dutch micro-costing study. All costs were measured from the hospital perspective (price level of 2006). Patients were followed in the model for 28 days. We also studied the sub-population where weaning had started within 72 hours.

RESULTS

The average total 28-day costs were €15,626 with RS versus €17,100 with CS, meaning a difference in costs of €1474 (95% CI -2163, 5110). The average length-of-stay (LOS) in the ICU was 7.6 days in the RS group versus 8.5 days in the CS group (difference 1.0, 95% CI -0.7, 2.6), while the average MV time was 5.0 days for RS versus 6.0 days for CS. Similar differences were found in the subgroup analysis.

CONCLUSIONS

Compared to CS, RS significantly decreases the overall costs in the ICU.

TRIAL REGISTRATION

Clinicaltrials.gov NCT00158873.

Role of macrophage colony-stimulating factor in polymicrobial sepsis according to studies using osteopetrotic (op/op) mice

BACKGROUND

The specific purpose of this study was to investigate the role of macrophage colony-stimulating factor (M-CSF)-induced macrophages in mouse polymicrobial sepsis model.

MATERIALS AND METHODS

M-CSF deficient (op/op) mice and their littermate mice w ere subjected the cecal ligation and puncture (CLP). Survival was assessed for the following 7 d after the CLP operation, and histopathologic findings were evaluated 12h after CLP. After CLP, expression of inflammatory mediators in serum was assessed by enzyme immunosorbent assay (ELISA). Furthermore, isolated peritoneal macrophages were stimulated with lipopolysaccharide (LPS) (10μg/mL) for 4h, and cytokine concentration in the supernatant was then measured by ELISA. Moreover, phagocytosis of isolated macrophages was assessed using fluorescent rates beads. In another set of experiments, effects of neutralization antibodies against high mobility group box 1 (HMGB1) were investigated in CLP model.

RESULTS

Mortality was increased in op/op mice compared with op/? mice after CLP. Furthermore, serum HMGB1 levels were also significantly greater in op/op mice than op/? mice. Production of HMGB1 by isolated peritoneal macrophages was significantly greater in op/op mice than op/? mice. Furthermore, the phagocytosis index was significantly blunted in op/op mice compared with op/? mice. Importantly, treatment with neutralization antibodies against HMGB1 markedly prevented acute lung injury and mortality in op/op mice.

CONCLUSION

Matured macrophages by M-CSF play pivotal role by scavenging endotoxin in inflammation. Furthermore, HMGB1 is involved in pathophysiology in polymicrobial sepsis, consistent with previous reports.

Pediatric intestinal and multivisceral transplantation: a new challenge for the pediatric intensivist

INTRODUCTION

With increasing survival rates, intestinal transplantation (ITx) and multivisceral transplantation have reached the mainstream of medical care. Pediatric candidates for ITx often suffer from severe multisystem impairments that pose challenges to the medical team. These patients frequently require intensive care preoperatively and have unique intensive care needs postoperatively.

METHODS

We reviewed the literature on intensive care of pediatric intestinal transplantation as well as our own experience. This review is not aimed only at pediatric intensivists from ITx centers; these patients frequently require ICU care at other institutions.

RESULTS

Preoperative management focuses on optimization of organ function, minimizing ventilator-induced lung injury, preventing excessive edema yet maintaining adequate organ perfusion, preventing and controlling sepsis and bleeding from varices at enterocutaneous interfaces, and optimizing nutritional support. The goal is to extend life in stable condition to the point of transplantation. Postoperative care focuses on optimizing perfusion of the mesenteric circulation by maintaining intravascular volume, minimizing hypercoagulability, and providing adequate oxygen delivery. Careful monitoring of the stoma and its output and correction of electrolyte imbalances that may require renal replacement therapy is critical, as are monitoring for and aggressively treating infections, which often present with only subtle clinical clues. Signs of intestinal rejection may be non-specific, and early differentiation from other causes of intestinal dysfunction is important. Understanding of the expanding armamentarium of immunosuppressive agents and their side-effects is required.

CONCLUSIONS

As outcomes of ITx improve, transplant teams accept patients with higher pre-operative morbidity and at higher risk for complications. Many ITx patients would benefit from earlier referral for transplant evaluation before severe liver disease, recurrent central venous catheter-related sepsis and venous thromboses develop.

High-dose intravenous immunoglobulin G improves systemic inflammation in a rat model of CLP-induced sepsis

OBJECTIVE

Intravenous immunoglobulin therapy has been proposed as an advanced treatment for sepsis. Yet, its benefit remains unclear and the mechanism of action is poorly understood. One key mediator in the development of sepsis is high mobility group box 1 (HMGB1). Therefore, we examined the serum and lung tissue levels of HMGB1 in a rat model of sepsis.

DESIGN AND SETTING

Prospective controlled animal study in a university laboratory.

MATERIALS

Rats received either cecal ligation and puncture-induced sepsis or had additional intravenous immunoglobulin treatment in boluses of 100, 300, or 1,000 mg/kg.

MEASUREMENTS AND RESULTS

After induction of sepsis and respective treatment conditions, histopathology, wet/dry weight ratios, and signaling molecules were examined in pulmonary tissue. Serum and pulmonary levels of cytokine and HMGB1 were measured. High dose intravenous immunoglobulin (1,000 mg/kg)-treated animals demonstrated significantly improved survival and pulmonary histopathology compared to the control rats. Serum and pulmonary HMGB1 levels were lower over time among intravenous immunoglobulin-treated animals. Furthermore, administration of intravenous immunoglobulin resulted in inhibition of NF-kappaB activity.

CONCLUSIONS

High-dose intravenous immunoglobulin decreased the mortality and pulmonary pathology in a rat model of sepsis. A significant reduction in HMGB1 levels was also observed, which may be mediated by inhibition of inflammation and NF-kappaB.

DESCRIPTOR

23. Acute respiratory distress syndrome (ARDS) and acute lung injury (ALI): experimental models.

Oral probiotic and prevention of Pseudomonas aeruginosa infections: a randomized, double-blind, placebo-controlled pilot study in intensive care unit patients

INTRODUCTION

Preventing carriage of potentially pathogenic micro-organisms from the aerodigestive tract is an infection control strategy used to reduce the occurrence of ventilator-associated pneumonia in intensive care units. However, antibiotic use in selective decontamination protocols is controversial. The purpose of this study was to investigate the effect of oral administration of a probiotic, namely Lactobacillus, on gastric and respiratory tract colonization/infection with Pseudomonas aeruginosa strains. Our hypothesis was that an indigenous flora should exhibit a protective effect against secondary colonization.

METHODS

We conducted a prospective, randomized, double-blind, placebo-controlled pilot study between March 2003 and October 2004 in a 17-bed intensive care unit of a teaching hospital in Clermont-Ferrand, France. Consecutive patients with a unit stay of longer than 48 hours were included, 106 in the placebo group and 102 in the probiotic group. Through a nasogastric feeding tube, patients received either 109 colony-forming units unity forming colony of Lactobacillus casei rhamnosus or placebo twice daily, from the third day after admission to discharge. Digestive tract carriage of P. aeruginosa was monitored by cultures of gastric aspirates at admission, once a week thereafter and on discharge. In addition, bacteriological analyses of respiratory tract specimens were conducted to determine patient infectious status.

RESULTS

The occurrence of P. aeruginosa respiratory colonization and/or infection was significantly delayed in the probiotic group, with a difference in median delay to acquisition of 11 days versus 50 days (P = 0.01), and a nonacquisition expectancy mean of 69 days versus 77 days (P = 0.01). The occurrence of ventilator-associated pneumonia due to P. aeruginosa in the patients receiving the probiotic was less frequent, although not significantly reduced, in patients in the probiotic group (2.9%) compared with those in the placebo group (7.5%). After multivariate Cox proportional hazards modelling, the absence of probiotic treatment increased the risk for P. aeruginosa colonization in respiratory tract (adjusted hazard ratio = 3.2, 95% confidence interval - 1.1 to 9.1).

CONCLUSION

In this pilot study, oral administration of a probiotic delayed respiratory tract colonization/infection by P. aeruginosa.

TRIAL REGISTRATION

The trial registration number for this study is NCT00604110.

High dose antithrombin III inhibits HMGB1 and improves endotoxin-induced acute lung injury in rats

OBJECTIVE

High mobility group box 1 (HMGB1) is an important factor in the development of sepsis. Previous work suggests that antithrombin III (ATIII) inhibits inflammation, but the mechanism of action is still poorly understood.

DESIGN AND SETTING

Prospective controlled animal study in a university laboratory.

MATERIALS

Rats were randomly divided into a lipopolysaccharide (LPS)-induced sepsis control group and an ATIII-treated experimental group. Animals in the experimental group received a bolus of 250 units/kg of ATIII injected into the tail vein.

MEASUREMENTS AND RESULTS

Animals receiving high-dose ATIII (250 units/kg) had significantly improved lung histopathology and survival compared to the control rats. We measured serum and lung levels of various cytokines and HMGB1 at regular intervals from 0 to 12 h after the induction of sepsis and demonstrated lower HMGB1 levels over time in ATIII-treated animals. In an in vitro experiment, we stimulated the mouse macrophage cell line RAW 264.7 with LPS in the presence or absence of ATIII. Subsequent measurement of HMGB1 concentrations in the supernatant and cell signaling molecules in cell lysates revealed an ATIII dose-dependent decrease in HMGB1 release. Furthermore, inhibition of IkB and p42 phosphorylation was observed with the administration of ATIII, suggestive of downstream signaling pathways.

CONCLUSIONS

High-dose ATIII decreases lung pathology and reduces mortality in a rat sepsis model. This finding may be mediated by the inhibition of HMGB1.

Genetic variants in the NOD2/CARD15 gene are associated with early mortality in sepsis patients

OBJECTIVE

Genetic variants in the NOD2/CARD15 gene resulting in a diminished capacity to activate NF-kappaB in response to bacterial cell wall products have been associated with Crohn's disease (CD). Recently, we found an association between the variant Leu1007fsinsC of the NOD2/CARD15 gene (SNP13) and a significantly increased rate of transplant related mortality (TRM) due to intestinal and pulmonary complications in stem cell transplantation (SCT). To assess a possible contribution of variants in the NOD2/CARD15 gene to sepsis related mortality (SRM) we investigated 132 prospectively characterised, consecutive patients with sepsis.

DESIGN AND PATIENTS

The three most common NOD2/CARD15 variants (Arg702Trp, Gly908Arg, and Leu1007fsinsC) were determined in 132 prospectively characterised patients with sepsis attended to three intensive care units at the University of Regensburg by Taqman PCR. NOD2/CARD15 genotype and major patients' characteristics were correlated with SRM.

RESULTS

Patient groups with and without NOD2/CARD15 variants did not differ in their clinical characteristics such as median age, gender, reason for admission or APACHE score; however, SRM (day 30) was increased in patients with NOD2/CARD15 coding variants (42 vs. 31%) and was highest (57%) in 8 patients carrying the Leu1007fsinsC variant (p < 0.05). Multivariate analysis demonstrated the Leu1007fsinsC genetic variant as an independent risk factor for SRM.

CONCLUSION

Our findings indicate a major role of NOD2/CARD15 coding variants for SRM. This may be indicative for a role of impaired barrier function and bacterial translocation in the pathophysiology of early sepsis related death.

De-escalation therapy rates are significantly higher by bronchoalveolar lavage than by tracheal aspirate

Objective

To assess outcomes with de-escalation therapy in ventilator-associated pneumonia (VAP).

Design

Prospective observational study.

Setting

Multidisciplinary intensive care unit.

Patients and participants

VAP was diagnosed by positive quantitative cultures of both tracheal aspirate and bronchoalveolar lavage (BAL) and treated appropriately for all significant isolates of tracheal aspirate and BAL in 143 patients who were assigned to de-escalation therapy by BAL or tracheal aspirate.

Interventions

None.

Measurements and results

Antibiotic therapy was de-escalated in 58 patients (40.5%), who had decreased mortality at day 15 (5.1% vs. 31.7%) and day 28 (12% vs. 43.5%) and shorter intensive care unit (17.2 ± 1.2 vs. 22.7 ± 6.3 days) and hospital (23.7 ± 2.8 vs. 29.8 ± 11.1 days) stay (p < 0.05). Of the 81 patients assigned to tracheal aspirate, the 17 (21%) who achieved de-escalation of therapy had reduced 15-day mortality (5.8% vs. 34.3%), reduced 28-day mortality (11.6% vs. 45.3%), and shorter intensive care unit (17.2 ± 1.6 vs. 22.4 ± 6.4 days) and hospital (23.1 ± 4.4 vs. 29.9 ± 11.1 days) stay (p < 0.05). Of the 62 patients assigned to BAL, the 41 (66.1%) who achieved de-escalation of therapy had decreased 15-day mortality (4.8% vs. 23.8%), decreased 28-day mortality (12.1% vs. 38%), and shorter intensive care unit (17.2 ± 1.1 vs. 23.2 ± 6 days) and hospital (23.8 ± 2.4 vs. 29.8 ± 11.4 days) stay (p < 0.05).

Conclusions

For patients with VAP who have had appropriate treatment and shown a favorable clinical response, mortality and duration of stay can be further improved by de-escalation therapy.

Ceftazidime improves hemodynamics and oxygenation in ovine smoke inhalation injury and septic shock

OBJECTIVE

To investigate ceftazidime in acute lung injury (ALI) and sepsis.

DESIGN AND SETTING

Prospective, randomized, controlled animal study in an investigational ICU at a university hospital.

INTERVENTIONS

Eighteen female Merino sheep were prepared for chronic study and subjected to smoke inhalation and septic challenge according to an established protocol.

MEASUREMENTS AND RESULTS

Whereas global hemodynamics and oxygenation remained stable in sham animals (no injury, no treatment), the injury contributed to a hypotensive-hyperdynamic circulation in the control group (smoke inhalation and sepsis, no treatment), as indicated by a significant increase in cardiac index) and heart rate and a drop in mean arterial pressure. Treatment with ceftazidime (smoke inhalation and sepsis, treatment group) stabilized cardiac index and heart rate and attenuated the decrease in mean arterial pressure. The deterioration in PaO2/FiO2 ratio and pulmonary shunt fraction (Qs/Qt) was significantly delayed and blunted by ceftazidime. At 24 h after injury a significant increase in airway obstruction scores of bronchi and bronchioles in both injured groups was observed. Ceftazidime significantly reduced airway obstruction vs. control animals. Whereas plasma nitrate/nitrite levels increased similarly in the two injured groups, lung 3-nitrotyrosine content remained at the baseline level in the ceftazidime group.

CONCLUSIONS

In ovine lung injury ceftazidime improves global hemodynamics and oxygenation not only by bacterial clearance but also via reduction in toxic nitrogen species such as 3-nitrotyrosine. Therefore ceftazidime appears as a clinically relevant adjunct in the common setting of sepsis-associated lung injury.

Posterior reversible encephalopathy syndrome in intensive care medicine

BACKGROUND

Posterior reversible encephalopathy syndrome (PRES) is a well-recognized clinico-neuroradiological transient condition. Early recognition is of paramount importance for prompt control of blood pressure or removal of precipitating factors and treatment of epileptic seizures or status epilepticus. Delay in the diagnosis and treatment may in fact results in death or in irreversible neurological sequelae.

DISCUSSION

PRES is characterized by headache, altered mental status, seizures, and visual disturbances and is associated with a number of different causes, most commonly acute hypertension, preeclampsia/eclampsia, and immunosuppressive agents. Clinical symptoms and neuroradiological findings are typically indistinguishable among the cases of PRES, regardless of underlying cause. Magnetic resonance studies typically show edema involving the white matter of cerebral posterior regions, especially parieto-occipital lobes but frontal and temporal lobes, and other encephalic structures may be involved.

CONCLUSIONS

Intensivists and other physicians involved in the evaluation of patients with presumed PRES must be aware of the clinical spectrum of the associated conditions, the diagnostic modalities, and the correct treatment.

Difference in reported pre-morbid health-related quality of life between ARDS survivors and their substitute decision makers

CONTEXT

Substitute decision makers may consider the pre-morbid health status of their critically ill loved one when making treatment decisions on her/his behalf.

OBJECTIVE

To compare estimates of pre-morbid health-related quality of life (HRQOL) obtained from survivors of the acute respiratory distress syndrome (ARDS) with those of their substitute decision makers using the Short Form 36 (SF-36).

DESIGN

Prospective cohort study.

SETTING

University-affiliated intensive care unit in Toronto, Canada.

PATIENTS

A sample of 46 ARDS survivors and their substitute decision makers drawn from a previously described cohort.

INTERVENTIONS

We measured agreement and differences between responses on the SF-36 obtained from survivors (at 3 months after ICU discharge) and their substitute decision makers (at study entry).

MEASUREMENTS AND RESULTS

Agreement was poor for all SF-36 components and differences reached significance in three domains. In multivariable analysis considering age; sex; Acute Physiology, Age, and Chronic Health Evaluation II score; and Lung Injury Score, only patient age was associated with the mean difference between estimates for the 'Mental Health' domain. On average, estimates of pre-morbid HRQOL obtained from substitute decision makers were lower than those obtained from survivors.

CONCLUSION

Agreement between estimates of pre-morbid HRQOL provided by ARDS survivors and their substitute decision makers was poor. Compared with survivors, proxies tended to provide lower estimates of pre-morbid HRQOL. Substitute decision making for incapacitated patients is an imperfect process during which family members may underestimate their loved ones' own perception of pre-morbid health status. Alternatively, survivors of critical illness may overestimate pre-morbid HRQOL.

Sedation and analgesia in German intensive care units: how is it done in reality? Results of a patient-based survey of analgesia and sedation

OBJECTIVE

This study carried out the first patient-oriented survey on the practice of analgesia and sedation in German intensive care units, examining whether the goals of early spontaneous breathing and awake, cooperative patients are achieved.

DESIGN

A postal survey was sent to 261 hospitals in Germany. Each hospital received three patient-oriented forms with questions regarding current agents and techniques for analgesia and sedation of a specific patient. Responses were obtained from 220 (84%) hospitals which returned 305 questionnaires.

RESULTS

Patients' Ramsay sedation scale was significantly higher in all phases of analgesia and sedation, indicating that the patients were more deeply sedated than currently intended by the therapist. Propofol was used for most of the patients during short-term sedation (57%) and during weaning (48%). The preferred agent for sedation longer than 72[Symbol: see text]h was midazolam (66%).

CONCLUSION

The choice of agents and techniques for analgesia and sedation in the intensive care unit thus follows the German guidelines. The fact that the patients were more deeply sedated than intended by the therapist in all phases of sedation may be due to the low use of sedation scales and clinical practice guidelines or to the lack of training in using these techniques.