Aurélie Bourgoin

Safety of sedation with ketamine in severe head injury patients: Comparison with sufentanil

ObjectiveThe aim of the study was to compare the safety concerning cerebral hemodynamics of ketamine and sufentanil used for sedation of severe head injury patients, both drugs being used in combination with midazolam. DesignProspective, randomized, double-blind study. SettingIntensive care unit in a trauma center. PatientsTwenty-five patients with severe head injury. InterventionsTwelve patients received sedation with a continuous infusion of ketamine-midazolam and 13 with a continuous infusion of sufentanil-midazolam. All patients were mechanically ventilated with moderate hyperventilation. Measurements and Main ResultsPrognostic indicators (age, Glasgow Coma Scale scores, computed tomography diagnosis, and Injury Severity Scale score) were similar in the two groups at study entry. Measurements were carried out during the first 4 days of sedation. The average infusion rates during this time were 82 ± 25 &mgr;g·kg−1·min−1 ketamine and 1.64 ± 0.5 &mgr;g·kg−1·min−1 midazolam in the ketamine group and 0.008 ± 0.002 &mgr;g·kg−1·min−1 sufentanil and 1.63 ± 0.37 &mgr;g·kg−1·min−1 midazolam in the sufentanil group. No significant differences were observed between the two groups in the mean daily values of intracranial pressure and cerebral perfusion pressure. The numbers of intracranial pressure elevations were similar in both groups. The requirements of neuromuscular blocking agents, propofol, and thiopental were similar. Heart rate values were significantly higher in the ketamine group on therapy days 3 and 4 (p < .05). With regard to arterial pressure control, more fluids were given on the first therapy day and there was a trend toward greater use of vasopressors in the sufentanil group. Sedative costs were similar in the two groups. ConclusionThe results of this study suggest that ketamine in combination with midazolam is comparable with a combination of midazolam-sufentanil in maintaining intracranial pressure and cerebral perfusion pressure of severe head injury patients placed under controlled mechanical ventilation.

Empirical antimicrobial therapy of septic shock patients: adequacy and impact on the outcome.

ObjectiveTo assess the adequacy of empirical antimicrobial therapy prescribed in septic shock patients and to evaluate the relationship between inadequate antimicrobial therapy and 30-day mortality. DesignProspective observational study. SettingMedical-surgical (16-bed) intensive care unit in an urban teaching hospital. PatientsA total of 107 patients requiring intensive care admission were prospectively evaluated during the 3-yr period of the study. InterventionsProspective patient surveillance and data collection and assessment of antimicrobial therapy according to microbiological documentation. Measurements and Main ResultsA source of infection associated with a microbiological documentation was identified in 78 of the 107 patients (72%). Empirical antimicrobial therapy consisted of a pivotal antibiotic (&bgr;-lactam) associated with an aminoglycoside (59 patients) or a fluoroquinolone (21 patients). Vancomycin was added in 14 patients. Sixty-nine of the 78 patients (89%) received an adequate antimicrobial therapy. The mortality rate of patients receiving an adequate antimicrobial therapy was 56%, and seven of the nine patients (78%) receiving an inadequate antimicrobial therapy died (p = .2). Among the 81 patients who were alive on day 3, antimicrobial therapy was modified in agreement to clinical status and microbiological documentation in 80% of cases, with de-escalation in 64% of cases. De-escalation consisted of withdrawing the nonpivotal antibiotic in 42% of patients or switching to a narrow-spectrum &bgr;-lactam antibiotic (22% of cases). ConclusionThe prescription of empirical antimicrobial therapy by a senior physician in agreement with practice guidelines made it possible to achieve a crude rate of 89% of adequate antimicrobial therapy in study patients. Inadequate antimicrobial therapy was associated with a 39% excess of mortality. A de-escalation of the empirical therapy was possible in 64% of patients.

Influence on outcome of ventilator-associated pneumonia in multiple trauma patients with head trauma treated with selected digestive decontamination*

ObjectiveVentilator-associated pneumonia is said to be associated with an increased mortality or a prolonged intensive care unit stay. In multiple trauma, the use of selective digestive decontamination has been reported to decrease morbidity and mortality associated with pneumonia. We performed a study to evaluate the attributable morbidity and mortality of ventilator-associated pneumonia in multiple trauma patients with head trauma treated with selective digestive decontamination. DesignProspective, matched-paired, case-control study. SettingIntensive care unit at a tertiary university hospital. PatientsDuring a 6-yr period, 324 consecutive multiple trauma patients with head trauma requiring mechanical ventilation for >48 hrs were prospectively followed for the development of VAP. Case-control matching criteria were as follows: 1) age difference within 5 yrs, 2) Glasgow coma scale within five categories, 3) injury severity score within 5 points, 4) APACHE II score within 5 points, 5) ventilation of control patients for at least as long as the cases. The selective digestive decontamination regimen was used in all patients (cases and controls): polymixin E, gentamicin, and amphotericin B. Systemic cefazolin (1 g three times a day) was given for the first 3 days of intensive care unit stay. Measurements and Main ResultsAnalysis was performed on 58 pairs that were matched with 100% of success The most common isolates recovered were Staphylococcus aureus (39%) and Haemophilus influenzae (22%). High-risk pathogens were rarely isolated:Pseudomonas aeruginosa (5.1%), Acinetobacter species (8.6%), and methicillin-resistant S. aureus (6.7%). The duration of mechanical ventilation and intensive care unit stay were increased in case patients (11.6 ± 1.7 and 22.7 ± 2.9 days, respectively) compared with control patients (9.4 ± 1.3 and 16.8 ± 2.9 days, respectively;p < .0006). Mortality was similar in both case (17%) and control (24%) patients. ConclusionVentilator-associated pneumonia did not seem to increase mortality of multiple trauma patients with head trauma who received selective digestive decontamination. Whether or not this conclusion applied to trauma patients not receiving selective digestive decontamination should be evaluated in further studies.

The Effects of Remifentanil on Endotracheal Suctioning-induced Increases in Intracranial Pressure in Head-injured Patients

In patients with severe traumatic brain injury, bronchotracheal toilet may be accompanied by deleterious variations in intracranial pressure (ICP). To avoid these effects, IV opioids have been proposed. Twenty mechanically-ventilated patients received 3 ascending IV doses of remifentanil: dose 1 (1 &mgr;g/kg bolus, 0.25 &mgr;g/kg/min infusion); dose 2 (2 &mgr;g/kg bolus, 0.5 &mgr;g/kg/min infusion); and dose 3: (4 &mgr;g/kg bolus, 1 &mgr;g/kg/min infusion). Endotracheal suction was performed 20 min after the beginning of infusion to assess coughing. Heart rate, ICP, mean arterial blood pressure (MAP), cerebral perfusion pressure (CPP), middle cerebral artery mean flow velocity (VMCA), and bispectral index were monitored throughout the 30-min study period. Twelve, 15, and 19 patients receiving dose 1, 2, and 3, respectively, required vasopressors to maintain CPP >60 mm Hg. Suctioning resulted in coughing in 16, 15, and 5 patients receiving dose 1, 2, and 3, respectively. An increase in ICP, without change in VMCA, corresponded to the reduction in MAP consistent with the preservation of autoregulation. Remifentanil used as a continuous infusion in head-injured patients is not an effective drug to block responses to suctioning.

Risk factors for late-onset ventilator-associated pneumonia in trauma patients receiving selective digestive decontamination

Objective To determine the independent risk factors for late-onset ventilator-associated pneumonia (VAP) in trauma patients receiving selective digestive decontamination (SDD).Design A 4-year, prospective cohort study of trauma patients meeting the following criteria: injury severity score >15, and duration of mechanical ventilation >5 days. Predictors of late-onset VAP occurrence were assessed by logistic regression analysis.Population All patients received SDD consisting of polymixin E, gentamicin, and amphotericin B applied in nostrils, mouth, and gut with a 3-day course of parenteral cefazolin. VAP was suspected on clinical and radiological signs, and confirmed by the presence of at least one microorganism at a concentration of at least 104 CFU/ml on the broncho-alveolar lavage.Measurement Independent risk factors for late-onset VAP.Results A late-onset VAP was diagnosed in 90 (56%) out of 159 patients. Predicting factors for late-onset VAP were: use of non-depolarizing muscle relaxant agents for intubation [3.4 (CI 1.08–10.73)], duration of intubation [1.06 (CI 1.01–1.17)], length of intensive care unit (ICU) stay [1.05 (CI 1.02–1.09)], and prior tracheal colonization [1.03 (CI 1.02–1.21)]. Exposure to prior antimicrobial treatment, except SDD, conferred protection [0.3 (0.12–0.74)].Conclusion This study confirms the role of duration of intubation, length of ICU stay, and prior tracheal colonization in the development of late-onset VAP. The results also highlight the importance of the initial management on the development of late-onset VAP. The type of neuromuscular blocking agents to intubate trauma patients should be evaluated in future studies.

Postoperative analgesia after caesarean section with transversus abdominis plane block or continuous infiltration wound catheter: A randomized clinical trial. TAP vs. infiltration after caesarean section

OBJECTIVE Single shot transversus abdominis plane (TAP) block and continuous local anesthetic infiltration wound catheter (CLAIWC) decreased the morphine consumption after caesarean section. The aim of this study was to compare the analgesic efficacy of CLAIWC and ultrasound-guided TAP block. METHOD Sixty patients undergoing caesarean section were prospectively randomized. After the caesarean section, the postoperative analgesia was randomized to either a CLAIWC localized below the fascia with an elastomeric pump for 48hours or a bilateral ultrasound-guided TAP block with injection of ropivacaine. Every patient had a morphine pump patient-controlled analgesia. The primary outcome was the morphine consumption during the first 48hours. Secondary outcomes were pain score levels, adverse effects of opioids, and patient satisfaction. Variables were collected during 48hours after the caesarean section. RESULTS Median cumulative 48-hour morphine consumption was 17 [8-51] mg in the TAP group versus 21 [7-34] mg in the CLAIWC group (P=0.3). We did not find a difference between the groups regarding pain, side effects and satisfaction scores. CONCLUSION As part of a multimodal analgesic regimen, there is no significant difference between the TAP block and CLAIWC for postoperative analgesia after a caesarean section.

Target-Controlled Infusion in Children

Target-controlled infusion (TCI) is a new technique for the administration of intravenous agents based on real-time pharmacokinetic calculations. Its aim is to control and maintain steady therapeutic levels of drugs with a narrow margin of safety. TCI systems are intended to be similar to the vaporizers for halogenated agents. This technique is increasingly used in adults thanks to the recent availability of a marketed system designed to deliver propofol (Diprifusor®). Its utilization is much more limited in children due to theoretical and practical limits (Table 1). This presentation will focus mainly on the applicability of the technique in children and on the available literature. The reader may find a more detailed discussion about TCI administration in two recent reviews.1,2 Tabele 1 Theoretical and practical constraints associated with TCI in children. Theoretical Practical • Pharmacokinetics: -dedicated parameter set • I.V. line management -blood-effect transfer parameter ke0 • Pharmacodynamics: -adequate concentrations • Lack of marketed device -hypnotic-opioid interaction

Clearsight™ use for haemodynamic monitoring during the third trimester of pregnancy – a validation study

BACKGROUND We assessed the validity of Clearsight™ as a non-invasive cardiac output and stroke volume monitoring device, comparing it with transthoracic echocardiography measurements during the third trimester of pregnancy. METHODS Measurements obtained from Clearsight™ were compared with those from echocardiography as the gold standard. The precision and accuracy of the Clearsight™ was measured using the Bland and Altman method. Clinical agreement with echocardiography was assessed using the agreement tolerability index. RESULTS Measurements were recorded from 44 pregnant women with a median [IQR range] gestational age of 33 [30-37] weeks. We found that Clearsight™ measurements presented a systematic overestimation of cardiac output, with mean bias [CI 95%] of 2.7 [2.3-3.0] L/min, with limits of agreement of  -0.1 to 5.4 L/min. It overestimated stroke volume, with a bias of 29.5 [25.0-33.4] mL and a limit of agreement of -1.6 to 60.1 mL. In addition, the analysis of cardiac output showed a percentage of error of 41% and intra-class correlation [CI 95%] of 0.37 [0.17 to 0.53, P <0.001]. For stroke volume, the percentage of error was 40% and intra-class correlation 0.16 [-0.1 to 0.34; P=0.27]. We found that agreement tolerability index scores were unacceptable. We evaluated the ability of the device to track changes in cardiac output by inducing a left lateral decubitus position, but the analysis was inconclusive. CONCLUSION The agreement between Clearsight™ and the echocardiography measurements of cardiac output and stroke volume were not within an acceptable range in the third trimester of pregnancy.