Lactate and venoarterial carbon dioxide difference/arterial-venous oxygen difference ratio, but not central venous oxygen saturation, predict increase in oxygen consumption in fluid responders.

OBJECTIVES: During circulatory failure, the ultimate goal of treatments that increase cardiac output is to reduce tissue hypoxia. This can only occur if oxygen consumption depends on oxygen delivery. We compared the ability of central venous oxygen saturation and markers of anaerobic metabolism to predict whether a fluid-induced increase in oxygen delivery results in an increase in oxygen consumption. DESIGN: Prospective study. SETTING: ICU. PATIENTS: Fifty-one patients with an acute circulatory failure (78% of septic origin). MEASUREMENTS: Before and after a volume expansion (500 mL of saline), we measured cardiac index, o2- and Co2-derived variables and lactate. MAIN RESULTS: Volume expansion increased cardiac index ≥ 15% in 49% of patients ("volume-responders"). Oxygen delivery significantly increased in these 25 patients (+32% ± 16%, p < 0.0001). An increase in oxygen consumption ≥ 15% concomitantly occurred in 56% of these 25 volume-responders (+38% ± 28%). Compared with the volume-responders in whom oxygen consumption did not increase, the volume-responders in whom oxygen consumption increased ≥ 15% were characterized by a higher lactate (2.3 ± 1.1 mmol/L vs. 5.5 ± 4.0 mmol/L, respectively) and a higher ratio of the veno-arterial carbon dioxide tension difference (P(v - a)Co2) over the arteriovenous oxygen content difference (C(a - v)o2). A fluid-induced increase in oxygen consumption greater than or equal to 15% was not predicted by baseline central venous oxygen saturation but by high baseline lactate and (P(v - a)Co2/C(a - v)o2 ratio (areas under the receiving operating characteristics curves: 0.68 ± 0.11, 0.94 ± 0.05, and 0.91 ± 0.06). In volume-nonresponders, volume expansion did not significantly change cardiac index, but the oxygen delivery decreased due to a hemodilution-induced decrease in hematocrit. CONCLUSIONS: In volume-responders, unlike markers of anaerobic metabolism, central venous oxygen saturation did not allow the prediction of whether a fluid-induced increase in oxygen delivery would result in an increase in oxygen consumption. This suggests that along with indicators of volume-responsiveness, the indicators of anaerobic metabolism should be considered instead of central venous oxygen saturation for starting hemodynamic resuscitation.

Plethysmographic variability index (PVI) accuracy in predicting fluid responsiveness in anesthetized children.

INTRODUCTION: Plethysmographic Variability Index (PVI) has been shown to accurately predict responsiveness to fluid loads in adults. The goal of this study was to evaluate PVI accuracy when predicting fluid responsiveness during noncardiac surgery in children. MATERIAL AND METHODS: Children aged 2-10 years scheduled for noncardiac surgery under general anesthesia were included. PVI was assessed concomitantly with stroke volume index (SVI). A response to fluid load was defined by an SVI increase of more than 15%. A 10 ml·kg(-1) normal saline intravenous fluid challenge was administered before surgical incision and after anesthetic induction. After incision, fluid challenges were administered when SVI values decreased by more than 15% or where judged necessary by the anesthesiologist. Statistical analyses include receiving operator characteristics (ROC) analysis and the determination of gray zone method with an error tolerance of 10%. RESULTS: Fifty-four patients were included, 97 fluid challenges administered and 45 responses recorded. Area under the curve of ROC curves was 0.85 [0.77-0.93] and 0.8 [0.7-0.89] for baseline PVI and SVI values, respectively. Corresponding gray zone limits were [10-17%] and [22-31 ml·m(-2)], respectively. PVI values exhibited different gray zone limits for pre-incision and postincision fluid challenges, whereas SVI values were comparable. PVI value percentages in the gray zone were 34% overall and 44% for challenges performed after surgical incision. DISCUSSION: This study found both PVI and prechallenge SVI to be accurate when used to predict fluid load response during anesthetized noncardiac surgery in children. However, a third of recorded PVI values were inconclusive.

Predictive factors of PACU stay after herniorraphy in infant: a classification and regression tree analysis.

INTRODUCTION: Herniorraphy is a common surgical intervention in infants, particularly in those born prematurely. Prematurity and perioperative sedation have been shown to be risk factors for postoperative apnea. However, their influence upon PACU stay duration has not been evaluated. The goal of this study was to investigate predictive factors for PACU stay in infants undergoing herniorraphy. MATERIAL AND METHODS: This study is a retrospective analysis of perioperative data in infants <6 months of age undergoing herniorraphy during the period November 2007-November 2009. Collected data included age, gestational age at birth, post-conceptional age, weight, weight at birth, type of anesthesia (spinal vs general), perioperative administration of opioids and paracetamol, duration of surgery, duration of PACU stay, and apnea in PACU. Data analysis used classification and regression trees (CART) with a 10-fold cross-validation. RESULTS: Two hundred and ninety-six patients were included in the analysis. Five parameters were found to predict the duration of PACU stay: a post-conceptional age below 45 weeks, prematurity, general anesthesia, postoperative opioid administration, and the use of intraoperative regional analgesia. CRT method allows constructing a decision tree with eight terminal nodes. The percentage of explained variability of the model and the cross-validation were 79.7% and 76.6%, respectively. DISCUSSION: Our study allows construction of an accurate predictive tree for PACU stay during herniorraphy in infants <6 months. Parameters found to influence the duration of PACU stay were related to anesthesia techniques and perinatal outcomes.

[Vancomycin-resistant Enterococcus in an epidemic situation: screening at admission for patients at risk of carriage]. / Entérocoques résistant aux glycopeptides dans un contexte endémo-épidémique. Stratégie d'isolement àl'admission des patients à risque.

OBJECTIVES: To evaluate a strategy based on screening and isolation at admission to a department of infectious diseases during an epidemic of vancomycin-resistant Enterococcus (VRE) at the University Hospital of Clermont-Ferrand. METHODS: Systematic screening for VRE by anal swabs began on November 15, 2004. Patients were isolated on admission if (a) they had been hospitalized more than 24 h in an at-risk department of our hospital or (b) they had received a course of wide-spectrum antimicrobial therapy for longer than 48 h in the three months preceding admission. Patients hospitalized in our department were screened weekly if they were treated with wide-spectrum antibiotics, had a urinary catheter left in place for one week, or were neutropenic. RESULTS: Through May 15, 2005, 12 (3.5%) of 341 swabs were found to be positive for VRE: eight were detected on admission and four during hospitalization. In all, 81 patients were isolated on admission. A case-control study confirmed that the criteria for patient isolation were indeed risk factors for VRE. Isolation was well accepted when it was clearly explained. No new case has been detected since March 2005. CONCLUSION: An isolation strategy based on known risk factors for VRE with systematic screening on admission appears to be an effective way to control an outbreak of VRE, perhaps in part because it helps to keep the medical staff alert to this problem. Isolation is well tolerated as long as it is explained clearly.

[The law number 2005-370 of April 22, 2005 concerning the patients' rights at the end-of-life: improvement of the withholding and withdrawing treatment decision-making process by an educational program. A monocenter prospective and retrospective pilot study]. / Loi n° 2005-370 du 22 avril 2005 relative aux droits des malades et à la fin de vie : amélioration du processus de décision de limitation et d'arrêt des traitements au moyen d'un programme pédagogique. Étude monocentrique prospective et rétrospective pilote.

OBJECTIVE: To assess the impact of an educational program on the quality of the end-of-life decision (EOLD). METHODS: Prospective study for 3 months in a surgical Intensive Care Unit (ICU) involving: staff training conferences and guidelines for documenting level-of-care staff conference; audit before and at 3 months; analysis of records for deceased patients. The main outcome measures the proportion of treatment-limitation in dying ICU patients; and the secondary outcomes the decision-making process and nurses' satisfaction. RESULTS: Eighty-three patients were included; among them, 14 with EOLD. Pre-death palliative strategy increased from 51 % to 85 % with a persisting improvement of practices after 2 years. All steps of EOLD decision-making processes were traced in all such cases, 85 % being based on the proposed guidelines. Nursing team's satisfaction rate almost doubled to 70 %. DISCUSSION: The study demonstrate staff members' capacity to quickly improve their procedures for palliative care when provided with appropriate tools to think about the process and come to a decision. Our data suggest the potential benefice to extend this program to the other specialties involved in the end-of-life process.