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Background: The esCCO monitor (ECG- estimated Continuous Cardiac Output, Nihon Kohden(®)) is a new non-invasive tool for estimating cardiac output (CO). It derives CO from the pulse wave transit time (PWTT) estimated by the ECG and the plethysmographic wave. An initial calibration is needed to refine the relation linking pulse pressure (measured by arterial pressure cuff) to PWTT. To assess the accuracy and reliability of the esCCO system, we performed an analysis of agreement of CO values obtained by transthoracic echocardiography (TTE)., Methods: Thirty-eight intensive care unit patients were prospectively included. CO was determined simultaneously using esCCO (CO(esCCO)) and TTE (CO(TTE)) as our reference method., Results: A total of 103 paired readings from 38 patients were collected. The correlation coefficient between CO(esCCO) and CO(TTE) was 0.61 (P<0.001). The Bland and Altman analysis corrected for repeated measures showed a bias of -1.6 litre min(-1) and limits of agreement from -4.7 to +1.5 litre min(-1), with a percentage error (2 sd/mean CO) of 49%. The correlation for CO changes was significant (R=0.63, P<0.001), but the concordance rate was poor (73%). Polar plot analysis showed an angular bias of -9° with radial limits of agreement from -54° to +36°. The bias appeared to correlate with systemic vascular resistance (R=-0.45, P<0.001)., Conclusions: In critically ill patients, the performance of the esCCO monitor was not clinically acceptable, and this monitor cannot be recommended in this setting. Moreover, the esCCO failed to trend CO data reliably.

Introduction: Remifentanil is a powerful morphinic agonist often ordered for anaesthesia. The use of peroperative large doses of this opioid increases the risk to develop postoperative hyperalgesia and acute tolerance. But how early these effects can occur? Despite the fact that these effects could be masked during the preoperative time because of general anaesthesia, it seems they could occur precociously. In order to try to describe this time, this study evaluated the acute tolerance under general anaesthesia requiring large doses of remifentanil by using an effective peroperative monitoring of nociception: the continuous pupillary diameter monitoring., Materials and Methods: In this prospective observational clinical study, a continuous infusion of remifentanil was started at a range of 0.3 microg/kg/min after induction of anaesthesia by using propofol (TIVA), remifentanil bolus and cisatracurium. The pupil monitoring started 10 min later (T+10 min) and lasted until the surgical incision (T+65 min). So, there was no surgical stimulus during this time., Results: Thirty patients undergoing major cardiac or vascular surgery were included in this study. The continuous pupil diameter evaluation showed a significant increase of the pupil diameter from T+45 min. No significant variation of heart rate, blood pressure, bispectral index (BIS) values were observed., Discussion: The development of acute remifentanil tolerance could possibly explain these results. If evaluations with continuous pupillary diameter monitoring are still limited, these results suggest that the use of powerful opioids such as remifentanil should be associated with a N-methyl-D-aspartate (NMDA) receptor antagonist agent, including short time administrations.

Objective: To review the current data on the duration of an antibiotic treatment., Methods: Analysis of recent and older articles on criteria of discontinuation of an antibiotic treatment in intensive care patients., Synthesis: In intensive care patients the initiation of an antibiotic therapy is more or less codified, in spite of numerous existing problems. The duration of its maintenance, although based on scientific data depends mainly on a multitude of variables. The first step is to assess the therapeutic efficiency in considering the regression of clinical manifestations, the normalization of the acute phase reactants, the sterility of bacteriological samples and the absence of relapse at therapy discontinuation. An assessment after 48 hours is essential, in order to decide the maintenance or the modification of therapy. Finally the indication of bitherapy is considered. The theoretical duration of antibiotic therapy is determined in taking into account the involved microbial agent(s), the centre of infection, the bacterial inoculum, the patient, the presence of foreign material, and the administered antibiotic.

The bactericidal activity of beta-lactams is time-dependent, and the time spent above the MIC (T > MIC) is the best predictor of efficacy. A prospective, randomized, open-label study was conducted in intensive care unit (ICU) patients with gram-negative rod infections to compare the efficacy of cefepime given as a continuous versus an intermittent infusion. Of the 18 patients included to date, 14 had severe pneumonia and four bacteremia. All patients received amikacin, 15 mg/kg/d, and cefepime, 4 g/d. Patients were randomized to cefepime administration as a continuous infusion (Group 1, n = 9) or as an intermittent infusion (Group 2, n = 9, 2 g every 12 h). No significant differences were found between the two groups for age, sex, initial infection, IGS II score (46 vs 48, NS) or the MIC of the gram-negative organism. Mechanical ventilation and hospital stay durations, recovery rates, and pharmacokinetic parameters (24-h AUIC, 12-h AUIC, T > MIC, and T > 5 x MIC) were compared in the two groups using the chi-square and Mann-Whitney tests. P values < 0.05 were considered statistically significant. There were no significant differences for mechanical ventilation duration, recovery rate, hospital stay duration (34 vs 36 days, NS), 24-h AUIC (624 vs 473, NS), or the 12-h AUIC (235 vs 238, NS). There were two interesting findings: T > MIC was significantly (P < 0.05) higher in Group 1 (23.84 +/- 0.2) than in Group 2 (20.7 +/- 3), and T > 5 x MIC was also significantly (P < 0.01) higher in Group 1 (23.61 +/- 0.6) than in Group 2 (16.6 +/- 6). Although clinical outcomes were similar in the two groups, it is reasonable to assume that the longer time spent with a cefepime level above the MIC in the continuous infusion group was associated with a more stable bactericidal effect.