Negative impact of hypocaloric feeding and energy balance on clinical outcome in ICU patients

Résumé Introduction : Les patients nécessitant une prise en charge prolongée en milieu de soins intensifs et présentant une évolution compliquée, développent une réponse métabolique intense caractérisée généralement par un hypermétabolisme et un catabolisme protéique. La sévérité de leur atteinte pathologique expose ces patients à la malnutrition, due principalement à un apport nutritionnel insuffisant, et entraînant une balance énergétique déficitaire. Dans un nombre important d'unités de soins intensifs la nutrition des patients n'apparaît pas comme un objectif prioritaire de la prise en charge. En menant une étude prospective d'observation afin d'analyser la relation entre la balance énergétique et le pronostic clinique des patients avec séjours prolongés en soins intensifs, nous souhaitions changer cette attitude et démonter l'effet délétère de la malnutrition chez ce type de patient. Méthodes : Sur une période de 2 ans, tous les patients, dont le séjour en soins intensifs fut de 5 jours ou plus, ont été enrôlés. Les besoins en énergie pour chaque patient ont été déterminés soit par calorimétrie indirecte, soit au moyen d'une formule prenant en compte le poids du patient (30 kcal/kg/jour). Les patients ayant bénéficié d'une calorimétrie indirecte ont par ailleurs vérifié la justesse de la formule appliquée. L'âge, le sexe le poids préopératoire, la taille, et le « Body mass index » index de masse corporelle reconnu en milieu clinique ont été relevés. L'énergie délivrée l'était soit sous forme nutritionnelle (administration de nutrition entérale, parentérale ou mixte) soit sous forme non-nutritionnelle (perfusions : soluté glucosé, apport lipidique non nutritionnel). Les données de nutrition (cible théorique, cible prescrite, énergie nutritionnelle, énergie non-nutritionnelle, énergie totale, balance énergétique nutritionnelle, balance énergétique totale), et d'évolution clinique (nombre des jours de ventilation mécanique, nombre d'infections, utilisation des antibiotiques, durée du séjour, complications neurologiques, respiratoires gastro-intestinales, cardiovasculaires, rénales et hépatiques, scores de gravité pour patients en soins intensifs, valeurs hématologiques, sériques, microbiologiques) ont été analysées pour chacun des 669 jours de soins intensifs vécus par un total de 48 patients. Résultats : 48 patients de 57±16 ans dont le séjour a varié entre 5 et 49 jours (motif d'admission : polytraumatisés 10; chirurgie cardiaque 13; insuffisance respiratoire 7; pathologie gastro-intestinale 3; sepsis 3; transplantation 4; autre 8) ont été retenus. Si nous n'avons pu démontrer une relation entre la balance énergétique et plus particulièrement, le déficit énergétique, et la mortalité, il existe une relation hautement significative entre le déficit énergétique et la morbidité, à savoir les complications et les infections, qui prolongent naturellement la durée du séjour. De plus, bien que l'étude ne comporte aucune intervention et que nous ne puissions avancer qu'il existe une relation de cause à effet, l'analyse par régression multiple montre que le facteur pronostic le plus fiable est justement la balance énergétique, au détriment des scores habituellement utilisés en soins intensifs. L'évolution est indépendante tant de l'âge et du sexe, que du status nutritionnel préopératoire. L'étude ne prévoyait pas de récolter des données économiques : nous ne pouvons pas, dès lors, affirmer que l'augmentation des coûts engendrée par un séjour prolongé en unité de soins intensifs est induite par un déficit énergétique, même si le bon sens nous laisse penser qu'un séjour plus court engendre un coût moindre. Cette étude attire aussi l'attention sur l'origine du déficit énergétique : il se creuse au cours de la première semaine en soins intensifs, et pourrait donc être prévenu par une intervention nutritionnelle précoce, alors que les recommandations actuelles préconisent un apport énergétique, sous forme de nutrition artificielle, qu'à partir de 48 heures de séjour aux soins intensifs. Conclusions : L'étude montre que pour les patients de soins intensifs les plus graves, la balance énergétique devrait être considérée comme un objectif important de la prise en charge, nécessitant l'application d'un protocole de nutrition précoce. Enfin comme l'évolution à l'admission des patients est souvent imprévisible, et que le déficit s'installe dès la première semaine, il est légitime de s'interroger sur la nécessité d'appliquer ce protocole à tous les patients de soins intensifs et ceci dès leur admission. Summary Background and aims: Critically ill patients with complicated evolution are frequently hypermetabolic, catabolic, and at risk of underfeeding. The study aimed at assessing the relationship between energy balance and outcome in critically ill patients. Methods: Prospective observational study conducted in consecutive patients staying 5 days in the surgical ICU of a University hospital. Demographic data, time to feeding, route, energy delivery, and outcome were recorded. Energy balance was calculated as energy delivery minus target. Data in means+ SD, linear regressions between energy balance and outcome variables. Results: Forty eight patients aged 57±16 years were investigated; complete data are available in 669 days. Mechanical ventilation lasted 11±8 days, ICU stay 15+9 was days, and 30-days mortality was 38%. Time to feeding was 3.1 ±2.2 days. Enteral nutrition was the most frequent route with 433 days. Mean daily energy delivery was 1090±930 kcal. Combining enteral and parenteral nutrition achieved highest energy delivery. Cumulated energy balance was between -12,600+ 10,520 kcal, and correlated with complications (P<0.001), already after 1 week. Conclusion: Negative energy balances were correlated with increasing number of complications, particularly infections. Energy debt appears as a promising tool for nutritional follow-up, which should be further tested. Delaying initiation of nutritional support exposes the patients to energy deficits that cannot be compensated later on.

Pre-hospital tracheal intubation in patients with traumatic brain injury: systematic review of current evidence.

BACKGROUND: We reviewed the current evidence on the benefit and harm of pre-hospital tracheal intubation and mechanical ventilation after traumatic brain injury (TBI). METHODS: We conducted a systematic literature search up to December 2007 without language restriction to identify interventional and observational studies comparing pre-hospital intubation with other airway management (e.g. bag-valve-mask or oxygen administration) in patients with TBI. Information on study design, population, interventions, and outcomes was abstracted by two investigators and cross-checked by two others. Seventeen studies were included with data for 15,335 patients collected from 1985 to 2004. There were 12 retrospective analyses of trauma registries or hospital databases, three cohort studies, one case-control study, and one controlled trial. Using Brain Trauma Foundation classification of evidence, there were 14 class 3 studies, three class 2 studies, and no class 1 study. Six studies were of adults, five of children, and three of both; age groups were unclear in three studies. Maximum follow-up was up to 6 months or hospital discharge. RESULTS: In 13 studies, the unadjusted odds ratios (ORs) for an effect of pre-hospital intubation on in-hospital mortality ranged from 0.17 (favouring control interventions) to 2.43 (favouring pre-hospital intubation); adjusted ORs ranged from 0.24 to 1.42. Estimates for functional outcomes after TBI were equivocal. Three studies indicated higher risk of pneumonia associated with pre-hospital (when compared with in-hospital) intubation. CONCLUSIONS: Overall, the available evidence did not support any benefit from pre-hospital intubation and mechanical ventilation after TBI. Additional arguments need to be taken into account, including medical and procedural aspects.

Successful bilateral lung transplantation after previous pneumonectomy.

We report successful bilateral lung transplantation for end-stage suppurative lung disease after a previous right-sided pneumonectomy performed for a destroyed lung. Our results demonstrate the feasibility of the procedure even in the context of mechanical ventilation and extracorporeal artificial oxygenation. Posttransplantation follow-up revealed excellent gas exchanges, no airway complications, and well-functioning grafts with right-sided ventilation and perfusion of 37% and 22%, respectively.

Devenir à long terme des patients intubés pour état de mal asthmatique [Late outcome after life-threatening asthma]

Pour connaître le devenir à long terme des patients intubés pour état de mal asthmatique, nous avons recontacté en 1990 les 34 patients qui avaient présenté, entre 1978 et 1988, quarante épisodes de détresse respiratoire aiguë. Deux patients sont vivants mais ont été perdus de vue, 3 sont morts dont un seul d'état de mal asthmatique 6 mois après l'épisode initial. Des 29 patients restants (7 hommes et 22 femmes, âge moyen de 48,5 ans) représentant un suivi moyen de 9,6 ans, quinze n'ont jamais été réhospitalisés; des 14 autres, seuls 5 ont requis une intubation et une ventilation mécanique lors d'un épiode ultérieur. La majorité des hospitalisations ultérieures (81%) sont survenues dans les 6 ans suivant l'épiode initial

Evaluation of the user-friendliness of seven new generation intensive care ventilators.

OBJECTIVE: To explore the user-friendliness and ergonomics of seven new generation intensive care ventilators. DESIGN: Prospective task-performing study. SETTING: Intensive care research laboratory, university hospital. METHODS: Ten physicians experienced in mechanical ventilation, but without prior knowledge of the ventilators, were asked to perform eight specific tasks [turning the ventilator on; recognizing mode and parameters; recognizing and setting alarms; mode change; finding and activating the pre-oxygenation function; pressure support setting; stand-by; finding and activating non-invasive ventilation (NIV) mode]. The time needed for each task was compared to a reference time (by trained physiotherapist familiar with the devices). A time >180 s was considered a task failure. RESULTS: For each of the tests on the ventilators, all physicians' times were significantly higher than the reference time (P < 0.001). A mean of 13 +/- 8 task failures (16%) was observed by the ventilator. The most frequently failed tasks were mode and parameter recognition, starting pressure support and finding the NIV mode. Least often failed tasks were turning on the pre-oxygenation function and alarm recognition and management. Overall, there was substantial heterogeneity between machines, some exhibiting better user-friendliness than others for certain tasks, but no ventilator was clearly better that the others on all points tested. CONCLUSIONS: The present study adds to the available literature outlining the ergonomic shortcomings of mechanical ventilators. These results suggest that closer ties between end-users and manufacturers should be promoted, at an early development phase of these machines, based on the scientific evaluation of the cognitive processes involved by users in the clinical setting.

Standardizing the diagnosis of inhalation injury using a descriptive score based on mucosal injury criteria.

INTRODUCTION: Inhalation injury is an important determinant of outcome in patients with major burns. However the diagnostic criteria remain imprecise, preventing objective comparisons of published data. The aims were to evaluate the utility of an inhalation score based on mucosal injury, while assessing separately the oro-pharyngeal sphere (ENT) and tracheobronchial tree (TB) in patients admitted to the ICU with a suspicion of inhalation injury. METHODS: Prospective observational study in 100 patients admitted with suspicion of inhalation injury among 168 consecutive burn admissions to the ICU of a university hospital. Inclusion criteria, endoscopic airway assessment during the first hours. ENT/TB lesion grading was 1: oedema, hyperemia, hypersecretion, 2: bullous mucosal detachment, erosion, exudates, 3: profound ulcers, necrosis. RESULTS: Of the 100 patients (age 42±17 years, burns 23±19%BSA), 79 presented an ENT inhalation injury ≥ENT1 (soot present in 24%): 36 had a tracheobronchial extension, 33 having a grade ≥TB1. Burned vibrissae: 10 patients "without" suffered ENT injury, while 6 patients "with" had no further lesions. Length of mechanical ventilation was strongly associated with the first 24 hrs' fluid resuscitation volume (p<0.0001) and the presence of inhalation injury (p=0.03), while the ICU length of stay was correlated with the %BSA. Soot was associated with prolonged mechanical ventilation (p=0.0115). There was no extubation failure. CONCLUSIONS: The developed inhalation score was simple to use, providing a unified language, and drawing attention to upper airway involvement. Burned vibrissae and suspected history proved to be insufficient diagnostic criteria. Further studies are required to validate the score in a larger population.

Überinfusion von Verbrennungsopfern: häufig und schädlich [Over infusion in burn victims: frequent and injurious]

Major burns are characterized by an initial capillary leak, which requires fluid resuscitation for hemodynamic stabilization. While under resuscitation was the major cause of death until the 1980s, over resuscitation has become an important source of complications, including abdominal compartment syndrome, escharosis, impaired gas exchange with prolonged mechanical ventilation and hospital stay. Fluid over infusion started in the 1990s with an increasing proportion of the fluid delivered within the first 24 h being well above the 4 ml/kg/% burn surface area (BSA) according to the Parkland formula. The first alerts were published in the form of case reports of increased mortality due to abdominal compartment syndrome and respiratory failure. This paper analyses the causes of this fluid over infusion and the ways to prevent it, which include rationing prehospital fluid delivery, avoiding early administration of colloids and prevention by permissive hypovolemia.

Abdominal infections in the intensive care unit: characteristics, treatment and determinants of outcome.

BACKGROUND: Abdominal infections are frequent causes of sepsis and septic shock in the intensive care unit (ICU) and are associated with adverse outcomes. We analyzed the characteristics, treatments and outcome of ICU patients with abdominal infections using data extracted from a one-day point prevalence study, the Extended Prevalence of Infection in the ICU (EPIC) II. METHODS: EPIC II included 13,796 adult patients from 1,265 ICUs in 75 countries. Infection was defined using the International Sepsis Forum criteria. Microbiological analyses were performed locally. Participating ICUs provided patient follow-up until hospital discharge or for 60 days. RESULTS: Of the 7,087 infected patients, 1,392 (19.6%) had an abdominal infection on the study day (60% male, mean age 62 ± 16 years, SAPS II score 39 ± 16, SOFA score 7.6 ± 4.6). Microbiological cultures were positive in 931 (67%) patients, most commonly Gram-negative bacteria (48.0%). Antibiotics were administered to 1366 (98.1%) patients. Patients who had been in the ICU for ≤ 2 days prior to the study day had more Escherichia coli, methicillin-sensitive Staphylococcus aureus and anaerobic isolates, and fewer enterococci than patients who had been in the ICU longer. ICU and hospital mortality rates were 29.4% and 36.3%, respectively. ICU mortality was higher in patients with abdominal infections than in those with other infections (29.4% vs. 24.4%, p < 0.001). In multivariable analysis, hematological malignancy, mechanical ventilation, cirrhosis, need for renal replacement therapy and SAPS II score were independently associated with increased mortality. CONCLUSIONS: The characteristics, microbiology and antibiotic treatment of abdominal infections in critically ill patients are diverse. Mortality in patients with isolated abdominal infections was higher than in those who had other infections.

Pneumocystis jirovecii genotype associated with increased death rate of HIV-infected patients with pneumonia.

Pneumocystis jirovecii dihydropteroate synthase (DHPS) mutations have been associated with failure of sulfa prophylaxis; their effect on the outcome of patients with P. jirovecii pneumonia (PCP) remains controversial. P. jirovecii DHPS polymorphisms and genotypes were identified in 112 cases of PCP in 110 HIV-infected patients by using PCR single-strand conformation polymorphism. Of the 110 patients observed, 21 died; 18 of those deaths were attributed to PCP. Thirty-three percent of the PCP cases involved a P. jirovecii strain that had 1 or both DHPS mutations. The presence or absence of DHPS mutations had no effect on the PCP mortality rate within 1 month, whereas P.jirovecii type 7 and mechanical ventilation at PCP diagnosis were associated with an increased risk of death caused by PCP. Mechanical ventilation at PCP diagnosis was also associated with an increased risk of sulfa treatment failure at 5 days.

Interhospital aeromedical transfers: need for a specific training

Introduction: The interhospital aeromedical transfers concern mainly unstable patients presenting with multiple organ failure and among whom the intensity, as well as the difficulty of care are often underestimated. Material and method: Retrospective analysis of 2094 interhospital transfers made by the Rega helicopter of Lausanne between 2003 and 2008, with description of the pathologies, the demographic characteristics, as well as the medical and technical difficulties. Results: Male patient are overrepresented (65 vs 35%), their age being 40-80 years old. On the other hand, we note an important number (10%) of patients less than 10 years. The average time of flight is 13 minutes, with a high rate of night transfers (34%). In 73% of the cases, the transfers concern medical, especially cardiovascular and neurological situations. Trauma and surgical situations account for less than 20%. The transferred patients often require mechanical ventilation (27%), as well as invasive measure of blood pressure (11%), particularly in cases of neurological, pulmonary or cardiac diseases. In 6% of the cases, we note a haemodynamic instability, requiring the use of catecholamines. In 1% a cardiopulmonary resuscitation was initiated during the flight. The overall mortality at 48 hours is about 5%. Conclusions: In spite of relatively brief flights, the complexity and the variety of the pathologies require a specific training for the medical teams involved in the transfers, concerning the aspects of resuscitation, mechanical ventilation, and the knowledge of advanced life support in paediatrics, traumatology and cardiopulmonary intensive care.

Surréanimation liquidienne pré et intrahospitatière des patients brûlés: fréquente et néfaste [Pre- and intra-hospital over-resuscitation in burns: frequent and deleterious].

Major burns are characterized by an initial capillary leak which requires fluid resuscitation for hemodynamic stabilisation. While under-resuscitation was the major cause of death until the 80ies, over-resuscitation has become an important source of complications: abdominal compartment syndrome, escharotomies, impaired gas exchange and prolonged mechanical ventilation and hospital stay. The fluid creep started in the 90ies with an increasing proportion of the first 24 hours' fluid delivery above the 4 ml/kg/% BSA Parkland prediction. The first alerts were published under the form of case reports of increased mortality due to abdominal compartment syndrome and respiratory failure. The paper analyses the causes of this fluid creep, and the ways to prevent it, which includes rationing prehospital fluid delivery, avoiding early colloids and permissive hypovolemia.

A randomized trial of glutamine and antioxidants in critically ill patients.

BACKGROUND: Critically ill patients have considerable oxidative stress. Glutamine and antioxidant supplementation may offer therapeutic benefit, although current data are conflicting. METHODS: In this blinded 2-by-2 factorial trial, we randomly assigned 1223 critically ill adults in 40 intensive care units (ICUs) in Canada, the United States, and Europe who had multiorgan failure and were receiving mechanical ventilation to receive supplements of glutamine, antioxidants, both, or placebo. Supplements were started within 24 hours after admission to the ICU and were provided both intravenously and enterally. The primary outcome was 28-day mortality. Because of the interim-analysis plan, a P value of less than 0.044 at the final analysis was considered to indicate statistical significance. RESULTS: There was a trend toward increased mortality at 28 days among patients who received glutamine as compared with those who did not receive glutamine (32.4% vs. 27.2%; adjusted odds ratio, 1.28; 95% confidence interval [CI], 1.00 to 1.64; P=0.05). In-hospital mortality and mortality at 6 months were significantly higher among those who received glutamine than among those who did not. Glutamine had no effect on rates of organ failure or infectious complications. Antioxidants had no effect on 28-day mortality (30.8%, vs. 28.8% with no antioxidants; adjusted odds ratio, 1.09; 95% CI, 0.86 to 1.40; P=0.48) or any other secondary end point. There were no differences among the groups with respect to serious adverse events (P=0.83). CONCLUSIONS: Early provision of glutamine or antioxidants did not improve clinical outcomes, and glutamine was associated with an increase in mortality among critically ill patients with multiorgan failure. (Funded by the Canadian Institutes of Health Research; ClinicalTrials.gov number, NCT00133978.).

Overall Burden of Healthcare-Associated Infections Among Surgical Patients: Results of a National Study.

OBJECTIVE:: To assess the overall burden of healthcare-associated infections (HAIs) in patients exposed and nonexposed to surgery. BACKGROUND:: Targeted HAI surveillance is common in healthcare institutions, but may underestimate the overall burden of disease. METHODS:: Prevalence study among patients hospitalized in 50 acute care hospitals participating in the Swiss Nosocomial Infection Prevalence surveillance program. RESULTS:: Of 8273 patients, 3377 (40.8%) had recent surgery. Overall, HAI was present in 358 (10.6%) patients exposed to surgery, but only in 206 (4.2%) of 4896 nonexposed (P < 0.001). Prevalence of surgical site infection (SSI) was 5.4%. Healthcare-associated infections prevalence excluding SSI was 6.5% in patients with surgery and 4.7% in those without (P < 0.0001). Patients exposed to surgery carried less intrinsic risk factors for infection (age >60 years, 55.6% vs 63.0%; American Society of Anesthesiologists score >3, 5.9% vs 9.3%; McCabe for rapidly fatal disease, 3.9% vs 6.6%; Charlson comorbidity index >2, 12.3% vs 20.9%, respectively; all P < 0.001) than those nonexposed, but more extrinsic risk factors (urinary catheters, 39.6% vs 14.1%; central venous catheters, 17.8% vs 7.1%; mechanical ventilation, 4.7% vs 1.3%; intensive care stay, 18.3% vs 8.8%, respectively; all P < 0.001). Exposure to surgery independently predicted an increased risk of HAI (odds ratio 2.43; 95% CI 2.0-3.0). CONCLUSIONS:: Despite a lower intrinsic risk, patients exposed to surgery carried more than twice the overall HAI burden than those nonexposed; almost half was accountable to SSI. Extending infection control efforts beyond SSI prevention in these patients might be rewarding, especially because of the extrinsic nature of risk factors.

Pneumocystis-carinii-Pneumonie bei Säuglingen mit vertikaler HIV-Infektion in der Schweiz [Pneumocystis carinii pneumonia in infants with vertically acquired HIV infection in Switzerland]

OBJECTIVE: Review of incidence, clinical picture, therapy, and outcome of Pneumocystis carinii pneumonia (PCP) in infants with vertically-acquired HIV infection in Switzerland. METHODS: Inquiry among members of the Swiss Pediatrics AIDS Group, review of the data base of the Swiss Neonatal HIV Study and retrospective analysis of the charts from infants with PCP. RESULTS: Since 1986 PCP has been diagnosed in 10 out of 107 infants with vertically-acquired HIV infection. PCP occurred in 7 infants at the age of 3-6 months and in 3 at the age of 9-11 months. 4 infants showed symptoms related to HIV infection before developing PCP. Before the development of PCP, infection with HIV had been ascertained in 6 infants. In 2 the diagnosis was still unclear and in the 2 remaining the risk of HIV infection was not known. None of the infants was on primary prophylaxis against PCP. Signs and symptoms of PCP included cough and tachypnea (100%) as well as high fever up to 40 degrees C (90%). Transcutaneous oxygen saturation was 70-95%. Chest X-rays revealed interstitial infiltrates in 6 infants, localized infiltrates in 2 and interstitial as well as localized infiltrates in 2. The CD4+ cell count was, with one exception, < 1500/microliters, i.e. below the normal value for age. Side effects of high dose cotrimoxazole were noted in 6 patients. 5 infants required intubation and mechanical ventilation. 4 infants died due to PCP, including 3 of those who required intubation and mechanical ventilation. CONCLUSIONS: PCP in infants with vertically-acquired HIV infection preferentially occurs at the age of 3 to 6 months and is often lethal, especially in patients requiring intubation. Evaluation for HIV infection should be done as early as possible in order to introduce primary PCP prophylaxis in infants at risk for this opportunistic infection.

Successful bilateral lung transplantation after previous pneumonectomy

Objective: To present the feasibility of bilateral lung transplantation after previously performed pneumonectomy.Methods: A 32 years old women underwent right pneumonectomy for bronchiectasis-related destroyed lung. Eight months later, she developed a vascular post-pneumonectomy syndrome and underwent realigning of the mediastinum by an intrathoracic expander that was complicated by an adult respiratory distress syndrome of the left lung requiring mechanical ventilation, arterio-venous CO2 removal (Novalung) and finally bilateral lung transplantation. Via clamshell incision, the post-pneumonectomy cavity was dissected and the superior vena cava (SVC) and carina were exposed. The pulmonary vessel stumps were dissected intrapericardically after realization of a right-sided hemi-pericardectomy. Extracorporeal circulation was started after central cannulation of the aorta and the inferior vena cava. A right upper lobe sleeve resection of the donor lung was performed. The intermediate bronchus was then implanted in the dissected recipient carina after realization of a hilar release maneuver. The right pulmonary artery was clamped between SVC andthe ascending aorta followed by end -to-end anastomosis of the donor and recipient artery and left atrial cuffs, respectively. Satisfactory graft function allowed decanulation and standard transplantation of the left lung without extracorporeal circulation.Results: Bronchoscopy and trans-esophageal echocardiography demonstrated a patent airway and vascular anastomoses without stenosis. Follow-up revealed excellent gas exchanges, no airway complications and well-functioning grafts on both sides with right-sided ventilation and perfusion two months after transplantation of 37% and 22%, respectively.Conclusion: This is to our knowledge the first report of successful bilateral lung transplantation after previous pneumonectomy unrelated to transplantation.