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Jean-Jacques Eledjam

Publications and source records attributed to Jean-Jacques Eledjam.

24 records · Page 2Linked to original sources
PubMed2002

Comparison of the effects of heat and moisture exchangers and heated humidifiers on ventilation and gas exchange during non-invasive ventilation.

OBJECTIVE: To compare the short-term effects of a heat and moisture exchanger (HME) and a heated humidifier (HH) during non-invasive ventilation (NIV). DESIGN: Prospective, clinical investigation. SETTING: Intensive care unit of a university hospital. PATIENTS: Twenty-four patients with acute respiratory failure (ARF). INTERVENTION: Each patient was studied with a HME and a HH in a random order during two consecutive 20min periods of NIV. MEASUREMENTS AND RESULTS: Respiratory rate (RR), expiratory tidal volume (VTe) and expiratory minute ventilation (VE) were measured during the last 5 min of each period and blood gases were measured. Mean pressure support and positive end-expiratory pressure levels were, respectively, 15+/-4 and 6+/-2 cmH(2)O. VE was significantly greater with HME than with HH (14.8+/-4.8 vs 13.2+/-4.3 l/min; p<0.001). This increase in VE was the result of a greater RR for HME than for HH (26.5+/-10.6 vs 24.1+/-9.8 breaths/min; p=0.002), whereas the VT for HME was similar to that for HH (674+/-156 vs 643+/-148 ml; p=0.09). Arterial partial pressure of carbon dioxide (PaCO(2)) was significantly higher with a HME than with a HH (43.4+/-8.9 vs 40.8+/-8.2 mmHg; p<0.005), without significantly changing oxygenation. CONCLUSION: During NIV the increased dead space of a HME can negatively affect ventilatory function and gas exchange. The effect of HME dead space may decrease efficiency of NIV in patients with ARF.

Acute Disease↗
PubMed2002

Regional blood flows are affected differently by PEEP when the abdomen is open or closed: an experimental rabbit model.

OBJECTIVE: The study of induced circulatory changes requires simultaneous assessment of multiple regional circulations because of interactions and compensatory mechanisms. Positive end expiratory pressure mechanical ventilation (PEEP) is known to cause marked, and potentially deleterious, cardiovascular changes. Our aim was to use a comprehensive approach to assess PEEP-induced circulatory changes in open vs closed abdomen animals. MATERIAL AND METHODS: In the anesthetized rabbit, we used implantable Doppler micro-probes to measure blood flow simultaneously in the ascending aorta, inferior vena cava, portal vein, hepatic artery, common carotid artery, and renal artery. We studied spontaneously breathing animals (Group A), and open (Group B) and closed abdomen (Group C) animals mechanically ventilated at 0 (ZEEP) and 12 cm H(2)O PEEP. RESULTS: In Group A, all biological and hemodynamic variables remained unchanged for three hours at the end of the surgical procedure. In Groups B and C, ZEEP produced no significant hemodynamic change. PEEP induced a decrease in carotid, hepatic, and renal artery blood flow in Groups B and C, a decrease in heart rate and mean arterial blood pressure in Group B, and a decrease in aorta blood flow in Group C. CONCLUSIONS: These experimental results demonstrate the usefulness of the comprehensive approach of circulatory changes, and confirm that PEEP may have deleterious effects on regional blood flow, even without significant change in cardiac output, especially when the abdomen is open.

Abdomen↗
PubMed2002

Comparison of the effects of racemic bupivacaine, levobupivacaine, and ropivacaine on ventricular conduction, refractoriness, and wavelength: an epicardial mapping study.

BACKGROUND: The study was designed to compare the effects of equimolar concentrations of racemic bupivacaine, levobupivacaine, and ropivacaine on ventricular conduction, anisotropy, duration and homogeneity of refractoriness, and wavelengths, and to provide a potency ratio for effects on conduction velocity. METHODS: Isolated frozen rabbit hearts (which leave a thin layer of surviving epicardial muscle) were treated with 0.1, 1, and 10 mum racemic bupivacaine, levobupivacaine, or ropivacaine. Left ventricular longitudinal and transverse conduction velocities, anisotropic ratio, minimum pacing cycle length, use dependency, duration and dispersion of ventricular effective refractory period, and wavelengths were studied. A high-resolution mapping system was used for data acquisition. In addition to two-way analysis of variance for repeated measures, data for conduction velocities were fitted simultaneously using a nonlinear mixed-effect modeling program to allow intergroup comparison. RESULTS: Each agent induced a concentration- and use-dependent slowing of conduction velocities, with no change of the anisotropic ratio. The use-dependent effect of levobupivacaine is similar to that of racemic bupivacaine concerning longitudinal conduction velocity. Fitting of conduction velocities provided a racemic bupivacaine to levobupivacaine and to ropivacaine ratio of 1:1.38 for concentration effect at 1,000-ms pacing cycle length, and 1:0.74 for use-dependent effect at 600-ms pacing cycle length. Racemic bupivacaine and levobupivacaine prolonged the ventricular effective refractory period, whereas ropivacaine did not. No dispersion in ventricular effective refractory period values occurred. All three agents induced significant decreases in wavelengths. This effect was not different among groups. CONCLUSIONS: Differences among racemic bupivacaine, levobupivacaine, and ropivacaine at equimolar concentrations are mainly caused by the use-dependent effects on conduction velocities and the concentration-dependent effects on ventricular effective refractory period. Therefore, one must take into account the corresponding pacing rates when comparing the potency ratios of local anesthetics.

Amides↗
PubMedDate not supplied

Parasacral approach to block the sciatic nerve: a 400-case survey.

BACKGROUND AND OBJECTIVES: Parasacral sciatic nerve block has been shown to be easy to perform, but studies reported to date involve a total of only 155 patients. The aim of this study was to assess the efficacy of parasacral sciatic nerve block in a larger group of patients. METHODS: Four hundred consecutive parasacral blocks were evaluated prospectively. The level of expertise of the practitioner, the time to perform the block, the lowest current intensity of nerve stimulation, the injected volume, the onset time, the success or failure of the block, and complications were recorded. RESULTS: The time required to perform the block was 7 +/- 5 minutes. The lowest stimulation-current intensity was 0.4 +/- 0.1 mA, and the injected volume was 27 +/- 4 mL. The onset time was 13 +/- 7 minutes for both motor and sensory block in all nerve distributions. The success rate was 94% (376 of 400 cases). Nine supplemental injections were performed successfully, thus increasing the success rate to 96%. General anesthesia or heavy sedation was performed in 15 cases (3.8%). There was no difference in failure rate between more experienced and less experienced anesthesiologists. CONCLUSIONS: In this prospective 400-case study, we confirmed previous findings that the parasacral approach is effective, easy to perform, and easy to teach, even when performed by relatively inexperienced physicians. The parasacral approach is, therefore, an effective alternative to other approaches of sciatic nerve blockade.

Adult↗
PubMedDate not supplied

Posterior perineal block with ropivacaine 0.75% for pain control during and after hemorrhoidectomy.

BACKGROUND AND OBJECTIVES: As perioperative pain management is a difficult challenge during hemorrhoidectomy, we tested the hypothesis that posterior perineal block (PPB) with local anesthetics alone is able to provide adequate pain control during and after surgery. METHODS: In a prospective, blinded, randomized study, we studied analgesic conditions and side effects of PPB in American Society of Anesthesiologists (ASA) I-II patients undergoing hemorrhoidectomy. Patients received general anesthesia (GA) either with PPB (0.75% ropivacaine, 40 mL (PPB group) or without PPB (control group). All patients received intravenous morphine patient-controlled analgesia (PCA) for postoperative pain control (morphine, 1.5 mg-boluses, 8-minute lockout interval). Intra- and postoperative opioids consumption was recorded, and pain assessments were performed at 1, 2, 4, 8, 12, and 24 hours using a visual analog scale (VAS). RESULTS: VAS scores were significantly lower during the first 8 postoperative hours in the PPB group as compared with the control group (P <.001). The PPB group required significantly less opioids during anesthesia (P <.001) and during the first postoperative day (P <.001) as compared with the control group. Time to first defecation and duration of hospitalization were identical in both groups. CONCLUSIONS: The present study shows that PPB with 40 mL 0.75% ropivacaine (300 mg) was a simple, effective, and safe method to provide better postoperative analgesia than PCA alone following surgical hemorrhoidectomy. In addition, PPB was shown to significantly reduce opioid consumption intraoperatively and during the first postoperative day.

Adult↗