J. J. De Waele

Development and validation of a model for prediction of mortality in patients with acute burn injury

The objective was to develop a user‐friendly model to predict the probability of death from acute burns soon after injury, based on burned surface area, age and presence of inhalation injury.

Determinants of prescription and choice of empirical therapy for hospital-acquired and ventilator-associated pneumonia

The objectives of this study were to assess the determinants of empirical antibiotic choice, prescription patterns and outcomes in patients with hospital-acquired pneumonia (HAP)/ventilator-associated pneumonia (VAP) in Europe. We performed a prospective, observational cohort study in 27 intensive care units (ICUs) from nine European countries. 100 consecutive patients on mechanical ventilation for HAP, on mechanical ventilation >48 h or with VAP were enrolled per ICU. Admission category, sickness severity and Acinetobacter spp. prevalence >10% in pneumonia episodes determined antibiotic empirical choice. Trauma patients were more often prescribed non-anti-Pseudomonas cephalosporins (OR 2.68, 95% CI 1.50–4.78). Surgical patients received less aminoglycosides (OR 0.26, 95% CI 0.14–0.49). A significant correlation (p<0.01) was found between Simplified Acute Physiology Score II score and carbapenem prescription. Basal Acinetobacter spp. prevalence >10% dramatically increased the prescription of carbapenems (OR 3.5, 95% CI 2.0–6.1) and colistin (OR 115.7, 95% CI 6.9–1,930.9). Appropriate empirical antibiotics decreased ICU length of stay by 6 days (26.3±19.8 days versus 32.8±29.4 days; p = 0.04). The antibiotics that were prescribed most were carbapenems, piperacillin/tazobactam and quinolones. Median (interquartile range) duration of antibiotic therapy was 9 (6–12) days. Anti-methicillin-resistant Staphylococcus aureus agents were prescribed in 38.4% of VAP episodes. Admission category, sickness severity and basal Acinetobacter prevalence >10% in pneumonia episodes were the major determinants of antibiotic choice at the bedside. Across Europe, carbapenems were the antibiotic most prescribed for HAP/VAP.

Rational intraabdominal pressure monitoring: how to do it?

Abstract Introduction: Intraabdominal hypertension (IAH) is increasingly appreciated by intensivists as an important cause of organ dysfunction, even at pressure levels which were previously thought to be harmless. Therefore, the goal of this review is to describe the different methods commonly used in clinical practice for intraabdominal pressure (IAP) measurement, the advised methodology for each measurement method, and finally to give a rational approach for IAP monitoring in daily clinical practice. Methods: A Medline search of the English literature was performed using the term “intra abdominal pressure” and “measurement”. This resulted in 194 studies, which were then analysed based on the title and abstract. Only clinical studies in human subjects with IAP measurement or related issues as the subject of the study, were considered for inclusion in the study. Reviews, animal experiments and case reports were excluded, while one specific review on IAP measurement and 3 large animal studies (domestic swine > 40 kg) were included in the analysis. This left us with 19 studies, published between 1984 and 2006: 1 specific review, 2 studies in children, 13 in adults and 3 in domestic swine. The references from these studies were searched for relevant articles that may have been missed in the primary search. These articles served as the basis for the recommendations below. Results: Clinical data regarding the validation of new IAP measurement methods or the reliability of established measurement techniques are scarce. The transvesical route, which has been studied most extensively, can be used as reliable route for intermittent IAP measurement, as long as instillation volumes below 25mL are used. Continuous IAP and APP monitoring can be done via a balloon-tipped catheter placed in the stomach or directly intraperitoneal. Conclusions: Rational IAP monitoring should be based on a site specific protocol, based on known risk factors, the monitoring equipment available and nursing staff experience, and should be linked directly to a local treatment protocol.

CONTINUOUS INTRA-ABDOMINAL PRESSURE MONITORING

Abstract Background: Intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) can develop within 12 hours of ICU admission in high-risk patients. Until recently the intermittent intra-abdominal pressure (IAP) measurement via the urinary catheter was the clinical standard. This is a relatively labour intensive technique and its intermittent nature could prevent timely recognition of significant changes in IAP. The historical continuous IAP (CIAP) measurements were poorly reproducible (gastric route) or invasive/impractical (direct measurement). The aim of this paper is to review the current evidence on CIAP monitoring. Methods: A broad Medline search of the English literature was performed using the terms of “intra abdominal pressure” and “continuous”. This result was analysed based on the title and abstract. Only original clinical studies with continuous IAP measurement were considered in this review. New techniques of CIAP monitoring evaluated in large animal models are discussed as potential future directions. Results: There is a growing evidence of measuring (monitoring) CIAP using several techniques (gastric, direct abdominal, inferior vena cava, and urinary bladder. The strongest evidence supports the direct abdominal, the gastric and the bladder route. From these three techniques the CIAP monitoring via the bladder has excellent agreement with the current standard of intermittent bladder pressure measurement. While the direct measurement could be very accurate it is an invasive method and feasible in patient who underwent laparotomy or laparoscopy. Conclusions: Until a better technique is available the CIAP monitoring via the bladder or stomach should be considered as the standard for continuous monitoring of the IAP. It is a less labour intensive, safe, less invasive and reliable method.

Temporal scanner thermometry: a new method of core temperature estimation in ICU patients.

Background and Aims: Temperature measurement is a routine task of patient care, with considerable clinical impact, especially in the ICU. This study was conducted to evaluate the accuracy and variability of the Temporal Artery Thermometer (TAT) in ICU-patients. Therefore, a convenience sample of 57 adult patients, with indwelling pulmonary artery catheters (PAC) in a 40-bed intensive care unit in a university teaching hospital was used. Methods: The study design was a prospective, descriptive comparative analysis. Body temperature was thereby measured simultaneously with the TAT and the Axillary Thermometer (AT), and was compared with the temperature recording of the PAC. The use of vasoactive medication was recorded. Results and conclusions: Mean temperature of all measurements was: PAC: 37.1°C (SD: 0.87), TAT: 37.0°C (SD: 0.68) and axillary thermometer: 36.6°C (SD: 0.94). The measurements of the TAT and the PAC were not significantly different (mean difference: 0.14°C; SD: 0.51; p= 0.33); whereas the measurements of the PAC and the AT differed significantly (mean difference: 0.46°C; SD: 0.39; p< 0.001). Mean difference in PAC versus TAT analyses, between patients with vasopressor therapy (0.12°C; SD: 0.55), and without vasopressor therapy (0.19°C; SD: 0.48) was not statistically significant (p= 0.47). Conclusion: We can conclude that the temporal scanner has a relatively good reliability with an acceptable accuracy and variability in patients with normothermia. The results are comparable to those of the AT, but they do not seem to be sufficient to prove any substantial benefit compared to rectal, oral or bladder thermometry.

RECOMMENDATIONS FOR RESEARCH FROM THE INTERNATIONAL CONFERENCE OF EXPERTS ON INTRA-ABDOMINAL HYPERTENSION AND ABDOMINAL COMPARTMENT SYNDROME

Abstract Objective. Intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) have been increasingly recognized in the critically ill over the past decade, and the number of published studies has exploded in recent years. Interpretation of the results and comparison of these studies is difficult, because of incomplete and inconsistent reporting of data and statistics. Design. An international consensus group of multidisciplinary specialists convened at the third World Congress on Abdominal Compartment Syndrome to develop recommendations for research related to the diagnosis and management of IAH and ACS. Methods. Prior to the conference the authors developed a blueprint for consensus definitions and treatment guidelines which were refined both during and after the conference. Results. Three major types of studies were identified (measurement techniques, epidemiology, and interventions), each with different needs regarding methodology, reporting of data and statistical analysis. Conclusions These recommendations are proposed to guide clinical research in the field of IAH and ACS

THE SECONDARY AND RECURRENT ABDOMINAL COMPARTMENT SYNDROME

Abstract Introduction: The Secondary Abdominal Compartment Syndrome (SACS) refers to cases of the ACS that do not originate from the abdominopelvic region. With greater awareness of the physiologic consequences of raised intra-abdominal hypertension (IAH), cases of the SACS are being increasingly described. The prior treatment or the presence of a partially open abdomen does not preclude the ACS if the abdomen and viscera continue to swell or the clinician is not vigilant in monitoring intra-abdominal pressure (IAP). Such recurrent cases (RACS) have been defined as those which redevelop following the previous medical or surgical treatment of primary or SACS. Although there has been a diverse range of etiologies implicated, these cases seem to be linked by the common occurrence of severe shock requiring aggressive fluid resuscitation. The aim of this paper is to thus to review the historical background, awareness, definitions, pathophysiological implications and treatment options for SACS and RACS. Methods: This review will focus on the available literature regarding SACS and RACS. A Medline and Pubmed search was performed using the keywords; secondary abdominal compartment syndrome AND secondary AND tertiary AND recurrent AND abdominal compartment syndrome AND intra-abdominal pressure AND intra-abdominal hypertension. Bibliographies of recovered papers were hand-searched for other appropriate references. The resulting references were included in the current review on the basis of relevance and scientific merit Results: There has been remarkably little specific study of these entities outside of specific groups such as those injured by thermal or traumatic injury. The epidemiology, risk factors for, treatment of and most importantly, strategies for prevention all remain scientifically unknown and therefore based on opinion. Notable, although small, studies suggest that specific resuscitation practices may avert these conditions. Conclusions: ACS can occur in any patient who is critically ill and subject to visceral and somatic swelling, regardless of whether the inciting pathology is extra-abdominal. The ACS may also reoccur with recurrent shock and swelling even if previous therapies had partially addressed IAH. Therefore IAP measurements should be considered a routine monitoring for the critically ill, especially those subjected to shock and requiring a subsequent resuscitation. Much further study is required to understand the differences in etiology, diagnosis, pathophysiology, and treatment for all cases of the ACS.

Coagulopathy, Hypothermia and Acidosis in Trauma Patients: the Rationale for Damage Control Surgery

Abstract Severe trauma to the torso or extremities often results in significant hemorraghe, which contributes to morbidity and mortality. The pathophysiological mechanisms contributing to this traumatic blood loss are complex. We review its major components: coagulopathy, acidosis and hypothermia, which have led to the concept of damage control surgery.

Factors associated with inadequate early vancomycin levels in critically ill patients treated with continuous infusion

Vancomycin administration using a loading dose and continuous infusion (CI) results in more rapid attainment of adequate concentrations. The aim of this retrospective study of ICU patients receiving vancomycin was to determine the efficacy of a vancomycin dosing protocol using a weight-based loading dose and to identify factors associated with inadequate concentrations. Patients received a loading dose (<65 kg, 1000 mg; ≥65 kg, 1500 mg), and 2000 mg/24 h CI with subsequent dose adaptation. Adequate levels were defined as concentrations ≥15 mg/L. In total, 227 patients (154 males) were included in the study (mean age 56.5 ± 16.1 years; mean APACHE II score 19.30 ± 7.7). The mean loading dose was 1129 ± 369 mg (15.07 ± 4.99 mg/kg). The dosing protocol was applied in 126 patients (55.5%). Mean vancomycin levels were 19.32 mg/L and 21.08 mg/L on Days 2 and 3, respectively. Vancomycin levels on Day 2 were adequate in 70.5% of patients, increasing to 84.1% on Day 3. Patients who received an appropriate loading dose more often had adequate vancomycin levels on Day 2. Older age, female sex, higher creatinine concentration, lower body temperature and use of a loading dose according to the vancomycin dosing protocol were independently associated with adequate vancomycin levels. A weight-based loading dose plus CI of vancomycin resulted in adequate concentrations in most patients and was superior compared with a non-standardised loading dose. Some patients may require higher doses, and factors other than weight, such as kidney function, age and sex, play a role.

Abdominal compartment syndrome and acute pancreatitis.

Abstract Significant visceral edema associated with massive fluid resuscitation, paralytic ileus and formation of pancreatic ascites in patients with severe acute pancreatitis (SAP) can lead to abdominal compartment syndrome (ACS) that can contribute to the early development of multiple organ dysfunction syndrome (MODS), especially in the early stages of the disease. The prevalence of intra-abdominal hypertension (IAH) in SAP is about 40% and a manifest ACS occurs in about 10% of the patients warranting close monitoring of intra-abdominal pressure (IAP) in all patients with the severe form of the disease. Although nonsurgical management utilizing percutaneous drainage of ascites or continuous hemodiafiltration may decrease IAP, most patients require decompressive laparostomy and temporary abdominal closure. The primary aim in managing the ensuing open abdomen is delayed fascial closure during initial hospitalization. On many occasions a planned hernia approach, either with early skin grafting over the exposed bowel or managing the ASC primarily with a subcutaneous linea alba fasciotomy, is the only available option. The development of ACS in patients with SAP seems to be associated with increased mortality.