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Background The sepsis syndromes, frequently complicated by pulmonary and cardiac dysfunction, remain a major cause of death amongst the critically ill. Targeted therapies aimed at ameliorating the systemic inflammation that characterises the sepsis syndromes have largely yielded disappointing results in clinical trials. Whilst there are many potential reasons for lack of success of clinical trials, one possibility is that the pathways targeted, to date, are only modifiable very early in the course of the illness. More recent approaches have therefore attempted to identify pathways that could offer a wider therapeutic window, such as the receptor for advanced glycation end-products (RAGE) and its ligands.

Improved patient survival and increasingly complex surgery have expanded the requirement for specialist care for patients with adult congenital heart disease (ACHD). Despite the recent publications of management guidelines for ACHD, data concerning optimal patterns of care in the peri-operative/critical care period of this challenging population are sparse. The aims of the current study were to therefore to determine the pattern of intensive care unit (ICU) management, resource utilisation and predictors of mortality in critically ill ACHD patients. Data were collected prospectively for patients with ACHD stratified for complexity of disease admitted to the ICU of a tertiary cardiothoracic centre (1997–2002). Multivariate analysis of pre-operative indices as predictors of mortality was performed. Of 342 ACHD admissions (total mortality 4.4%, simple 0%, moderate/complex 10.6%), the requirement for specialist investigations and interventions was high, reflected in ICU admission costs per patient (simple $5391 ± 130, moderate $13218 ± 261, complex $30074 ± 689). Standard severity of illness scoring systems did not accurately predict mortality; however, abnormal pre-operative thyroid function (p = 0.0048), creatinine (p = 0.0032) and bilirubin (p = 0.0021) were highly predictive of mortality. Peri-operative mortality in patients with ACHD is low overall but varies with disease complexity. Such patients have a high requirement for specialist ICU investigation/intervention. Although standard severity of illness scoring is unhelpful, simple pre-operative parameters may predict peri-operative mortality. These findings reflect the requirement for specialist care, and have implications for planning service provision, training and operative consent in ACHD patients.

Volume resuscitation is clinically beneficial in patients with sepsis, but few data exist concerning the effects of fluid administration on early events in the inflammatory process. Vascular permeability, leukocyte rolling and leukocyte adhesion in the rodent mesenteric microcirculation were assessed in vivo using intravital microscopy, and the effect of fluid administration on lipopolysaccharide (LPS)-induced changes recorded. Prospective, repeated measures study. University hospital laboratory. Male Wistar rats in six groups. All animals underwent intravital microscopic examination of mesenteric post-capillary venules. LPS or vehicle was applied topically. Animals received either no additional fluids, 0.9% saline (16 ml/kg per h) or 5% human albumin (16 ml/kg per h) commencing 30 min prior to LPS/vehicle administration. Leukocyte rolling, firm adhesion and blood velocity were observed directly. Vascular permeability was assessed using the flux of fluorescently labelled albumin into the interstitium. LPS significantly increased the median (IQR) number of leukocytes rolling and firmly adherent relative to baseline (at 60 min rolling increased from 12.0 (10.3–13.8) to 40.3 (36.0–47.5) cells/min; adhesion increased from 1 (1–2) to 17 (12–26) cells/100 μm; n=5, p

The Round Table on Acute Lung Injury proved a stimulating forum for the interchange of ideas regarding the state of the field and afforded many opportunities for scientific interaction — both during and outside the formal program. The participants are indebted to the European Society of Intensive Care Medicine and to the American Thoracic Society for their sponsorship, as well as to the local organizing committee and secretariat for coordinating a professionally valuable and memorable educational event.

Objective: To assess plasma iron status in critically ill patients with septic shock. Design: Observational, prospective study. Setting: Adult intensive care units in teaching and tertiary referral hospitals. Patients and participants: Fifteen adult patients with established septic shock. Normal control subjects (n = 10) were also investigated. Data from patients and controls were compared with previously published iron values in critical care patients. Measurements and results: The indices investigated and correlated with clinical scores of illness severity included bleomycin-detectable iron, non-haem iron; transferrin and its percentage iron saturation, and the iron binding (anti-oxidant) activity of transferrin. Bleomycin-detectable iron was not present in the plasma of patients with septic shock whilst the plasma transferrin remained unsaturated with iron. One patient in multi-organ failure displayed bleomycin-detectable iron in plasma (1.16 μmol/l) and had 100 % iron-saturation of transferrin. The plasma non-haem iron levels (7.84 ± 1.82 μmol/l) were the lowest of all critical care patient groups studied by us. The plasma transferrin levels were also low but resulted in a near normal percentage saturation of transferrin with iron (34.6 ± 6.5 %). The scores of clinical severity correlated with changes in plasma iron chemistry. Conclusions: Patients with septic shock rarely have iron saturated transferrin in their plasma leading to the presence of bleomycin-detectable iron.

No measurement of myocardial performance currently available in the ICU can be regarded is ideal. Table 2 summarises the main features of the major monitoring techniques. As many of the indices of myocardial performance are interdependent, quantifying the contribution of each component to overall cardiac function is not possible currently, and the clinical utility of monitoring each individually is not therefore established. Bedside measurements of LV dimensions, volumes and ejection fraction, and the other indices of systolic and diastolic function can now be made, but the case for their routine use in influencing clinical practice remains unproven. Transoesophageal echocardiography has an important and established diagnostic role and has been used successfully for continuous monitoring during surgery, but practical considerations seriously limit its potential for routine use. Radionuclide techniques allow the measurement of many of the same parameters and have the potential for continuous use, but practical problems and the additional risk of radiation exposure may limit this application in the critical care environment. Doppler techniques are non-invasive, provide continuous data and are simple to operate, but the data provided has important limitations. Although the pulmonary artery catheter has been in use for over twenty years, questions regarding the information is provides concerning myocardial function remain and the extent to which it should influence therapeutic decisions is still controversial. However with the development of additional facilities, particularly the continuous measurement of cardiac output the pulmonary artery catheter seems likely to remain the mainstay of bedside monitoring of myocardial performance in the critically ill in the immediate future.

To study the impact of continuous veno-venous haemofiltration on survival in patients with acute renal failure (ARF) following cardio-pulmonary bypass (CPB) surgery. A retrospective study of all patients requiring haemofiltration after CPB over a 2 year period. A 20 bedded, adult cardothoracic intensive care unit in a postgraduate teaching hospital. 35 patients (26 male, age range 24–74 years) required haemofiltration (2.7% of the total number of patients undergoing CPB). Cardiovascular failure post CPB was the commonest causes of ARF (n=16). Indications for haemofiltration were ureamia (21), oligo-anuria (11), volume overload (2) and hyperkalaemia (1). Mean time from CPB to the initiation of haemofiltration was 8 days (range 0–15 days). Mean urea was 30 mmol/l and creatinine 362 μmol/l immediately prior to treatment. Urea was well-controlled in all patients, although 2 needed haemodiafiltration. Twenty-six patients died during their admission to the ICU (74% mortality). A further 3 patients died during their hospital admission, following discharge from ICU. Outcome was particularly poor in patients with cardiovascular failure following CPB (16 cases, 0 survivors). Survivors tended to commence filtration earlier (mean of 4 vs 7 days for non-survivors) and required treatment for a mean period of 8 days (range 1–26 days). Survival was determined by the number of failed organ systems at the start of haemofiltration. Thus, 100% of patients with single system failure survived, compared to only 10% with 3 or more system failure. Despite the theoretical advantages of haemofiltration and the effective control of uraemia the mortality associated with ARF following CPB remains high and is probably determined by the number of failed organs systems.

Systemic inflammatory response syndrome (SIRS) is the leading cause of morbidity and mortality in the critically ill. It is associated with a 50% reduction in 5-year life expectancy. SIRS is defined as two of the following criteria: heart rate >90 beats/min, respiratory rate >20 breaths/min or pCO2 38°C, white cell count 12 × 109/l. These criteria are used to stratify patients for specific therapies and in research to define interventional groups. Cardiac surgery is associated with systemic inflammation. We undertook to describe the incidence of SIRS post cardiac surgery and relate this to outcome.

International guidelines concerning the management of patients with sepsis, septic shock and multiple organ failure make no reference to the nature of the infecting organism. Indeed, most clinical signs of sepsis are nonspecific. In contrast, in vitro data suggest that there are mechanistic differences between bacterial, viral and fungal sepsis, and imply that pathogenetic differences may exist between subclasses such as Gram-negative and Gram-positive bacteria. These differences are reflected in different cytokine profiles and mortality rates associated with Gram-positive and Gram-negative sepsis in humans. They also suggest that putative anti-mediator therapies may act differently according to the nature of an infecting organism. Data from some clinical trials conducted in severe sepsis support this hypothesis. It is likely that potential new therapies targeting, for example, Toll-like receptor pathways will require knowledge of the infecting organism. The advent of new technologies that accelerate the identification of infectious agents and their antimicrobial sensitivities may allow better tailored anti-mediator therapies and administration of antibiotics with narrow spectra and known efficacy.

Increasing numbers of patients with congenital heart disease now survive to adulthood, requiring repeated surgical and cardiological interventions that necessitate ICU admission [1]. There are little data in the literature regarding the ICU morbidity and mortality in this patient population. We therefore evaluated the ICU respiratory morbidity in patients with adult congenital heart disease (ACHD).

Current estimations suggest there are around 800,000 patients in the USA with congenital cardiac lesions requiring specialist care [1]. Improved surgical and cardiological interventions mean that numbers of patients with moderate-severe congenital lesions will increase [2], resulting in increased requirement for repeat surgery in adulthood. This is reflected by an increasingly complex case mix requiring ICU admission. The potential impact of this changing patient population upon ICU resources has not been addressed.