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R Chacornac

Publications and source records attributed to R Chacornac.

At least 19 recordsLinked to original sources
PubMed1997

[Decision to limit or practise maximum therapeutic support in a neurosurgical intensive care unit].

OBJECTIVE: To assess the respective rates of intensive care maximalization, limitation and withdrawal practice in a neurosurgical intensive care unit. STUDY DESIGN: Prospective clinical study. PATIENTS: All patients who died in the unit during the year 1994 were included in this study. METHODS: Demographic data and medical history of these patients were collected, and treatments during the last days and the 24 hours before death were reviewed. RESULTS: Among the 49 cases collected during the study period, 16 patients (33%) received full intensive therapy until their death. In 29 (59%), death was preceded by some limitation of treatment, and in 4 (8%) life-sustaining treatment (mechanical ventilation, vasopressor infusion) had not been undertaken. CONCLUSION: This prospective study confirmed the results of several previous surveys. The medical decision to limit or to discontinue treatments is rather frequent in intensive care units. This is an illegal practice in French legislation and code of professional ethics. Recommendations by representative French medical associations on the modalities of decision making on limitation of therapy would be welcome.

Adolescent↗
PubMed1995

[Aseptic meningitis. Demonstration of bacterial DNA in cerebrospinal fluid by gene amplification].

OBJECTIVE: To develop a diagnostic tool to recognize whether a postoperative meningitis occurring in neurosurgical patients is of bacteriological origin or not, in detecting in CSF bacterial DNA with the polymerase chain reaction (PCR) technique. STUDY DESIGN: Laboratory study. PATIENTS: Twenty-seven neurosurgical ICU patients associating, in the postoperative period, the CDC criteria of meningitis and a neutrophil polymorphonuclear count over 100 cells.mm-3 were allocated either into the MB+ group (n = 7) when their CSF culture was positive or in the MB- group (n = 20) when the culture was sterile. The CSF of 43 neurosurgical ICU patients without postoperative clinical and biological features of meningitis acted as controls. Sixteen specimens out of the 43 were inoculated with bacteria at a known concentration. METHODS: The CSF specimens of all patients were tested for the presence of eurcaryote DNA using the PCR technique. Beforehand its sensitivity had been assessed using the inoculated CSF of control group: a positive amplification at 20 cycles was equivalent to 10(5) CFU.mL-1 and a positive amplification at 25 cycles to 10(3) CFU.mL-1. RESULTS: In the 43 sterile control CSF specimens the amplification was negative in all at 20 cycles and in 42 at 25 cycles. In the 16 previously sterile control specimens supplemented with bacteria, as well as in the CSF of all 7 patients of MB+ group the amplification was positive at 20 and 25 cycles. In those of MB- group the amplification was negative in all at 20 cycles, but was positive in 19 out of 20 at 25 cycles. Southern blot with specific procaryote probes was positive with amplification products from CSF of MB+ and MB- groups and negative with control CSFs and human DNA. DISCUSSION: The presence of bacteria in CSF of patients sustaining a meningitis can be accurately detected through their DNA. Postoperative aseptic meningitides may have a bacterial origin. PCR can be used as a routine technique to provide a diagnosis of bacterial meningitis in less than 6 hours. Additionally specific oligonucleotides allow to identify the bacteria in less than 12 hours.

Adolescent↗
PubMed1995

[Cerebrovascular reactivity to CO2 during general anesthesia maintained with either isoflurane-N2O or propofol-N2O. A comparative study by transcranial Doppler velocimetry].

OBJECTIVES: To compare, using transcranial doppler velocimetry (TDV), the cerebral blood flow velocity and CO2 reactivity during general anaesthesia maintained with either isoflurane-N2O-O2(IF) or propofol-N2O-O2 (PF) in adults with a normal brain. STUDY DESIGN: Nonrandomized controlled trial. PATIENTS: Forty ASA I patients (mean age 41 +/- 13 yrs, 15 F/35 M) undergoing surgery of the lumbar spine in prone position. The first 20 were allocated into the IF group and the subsequent 20 into the PF group. METHODS: General anaesthesia was induced with midazolam (0.05 mg.kg-1), phenoperidine (0.03 mg.kg-1), thiopentone (5 mg.kg-1), vecuronium (0.1 mg.kg-1) and maintained with N2O (50 vol %) and O2 (50 vol %) and either isoflurane (0.8 < Fet < 1 vol %) in IF group or propofol (6 mg.kg-1.h-1) in PF group. The vascular reactivity was assessed with velocimetry measurements (Angiodine DMS, with a probe transmitting a 2-MHz pulsed wave) of flow in the middle cerebral artery at a given PetCO2 (obtained by adjustments of VT) during systole (SV) and diastole (DV). Three measurements were made: at T1 (PetCO2 = 30 +/- 2 mmHg), at T2 (PetCO2 = 40 +/- 2) and at T3 (PetCO2 = 30 +/- 2 mmHg). RESULTS: In the IF group, VS increased by +32% at T2 (P = 0.006) with an increase of + 3.4 %/1 mmHg of PetCO2. Similarly, in the PF group VS increased by + 31 % at T2 (P < 0.0001) with an increase of 2.9 %/1 mmHg of PetCO2. In both groups the VS returned to baseline values at T3. In the IF group, VD increased by + 66% at T2 (P < 0.0001), with an increase of + 7%/1 mmHg of PetCO2. Similarly in the PF group, VD increased by + 61% (P < 0.0001) with an increase of + 5.7%/1 mmHg of PetCO2. In both groups the VD returned to baseline values at T3. CONCLUSIONS: During anaesthesia maintained with either isoflurane-N2O-O2 or propofol-N2O-O2, a change in PetCO2 results in similar changes in VS and VD. These anaesthetic agents preserve the cerebrovascular reactivity of the normal brain. The results of this study are in accordance with those obtained with other reference techniques in healthy volunteers. Transcranial doppler velocimetry can be a useful noninvasive tool of clinical research in neuroanaesthesia.

Adult↗
PubMed1994

[Value of D(-) lactate determination for the fast diagnosis of meningitis after craniotomy. An initial study].

The early diagnosis of postoperative bacterial meningitis (BM) may be difficult. CSF cultures may remain sterile. Clinical features and routine laboratory data often fail to give an evidence. As early antibiotic therapy is essential in such patients, a rapid diagnosis is required. Different authors proposed the D(-) isomer of lactic acid as an early and effective marker of infection in the body fluids (including CSF). D(-) lactate is produced by bacteriae and fungi; L(+) lactate may be produced also by human tissues in anaerobic situations. We conducted a prospective study in a neurosurgical intensive care unit to evaluate this technique for the diagnosis of meningitis following craniotomy. Fifty-four patients were included, 40 in group A (not infected or infected out of the CNS), 4 in group B (suspected BM), 10 in group C (BM with positive CSF cultures). No patient suffered from septicemia, haemodynamic or ventilatory instability, nor metabolic disorder. Clinical data, CSF and blood samples (cytology, conventional biochemistry, D(-) and L(+) lactate, bacteriology) were collected at inclusion and, in group B and C patients, at day 2, 5 and at clinical recovery. D(-) lactate measurements were performed with an enzymatic method adaptated from a Boehringer Mannheim kit (for determination in foodstuff). Statistics were based on the comparison of group A vs C patients. D(-) and L(+) lactate concentrations in the CSF were significantly higher in group C patients, and blood concentrations were similar.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1994

[Indications of planned sedation following intracranial neurosurgery. Prospective study of decisional criteria].

General Anaesthesia (GA) is usually stopped early after intracranial surgery. An impaired neurological status or surgical difficulties may lead to sedate some patients (pts) in the intensive care unit (ICU). The aims of the study were to establish and to evaluate predictive criteria for post- operative sedation. In one group (G1), GA and mechanical ventilation (MV) were discontinued early after surgery and pts stayed at least 12 h. in the ICU. In the other group (G2), sedation and MV were prolonged 24 h., until a clinical and scannographic evaluation. Thereafter, sedation was discontinued or prolonged according to both surgical and anesthetic considerations. These criteria were established according to the literature and to local practices. Before surgery, they depended on clinical status, radiological data and etiology; during surgery, on surgical and medical semiology and difficulties or incidents during the procedure. Adult pts undergoing intracranial surgery under GA were consecutively included in a 6 months prospective study. Patients suffering acute head trauma, pre operative coma (Glasgow CS < 8) or extraneurologic disease (responsible for delayed MV weaning) were not included. Sedation was performed with midazolamR (.05-.15 mg.kg-1.h-1) + phenoperidineR without myorelaxation. The ideal level of sedation was established as defined by Boeke. One hundred and ninety five pts (80 f; 49 +/- 15y-o) were included (G1 = 130, G2 = 65). Surgical indications were: malignant tumor = 61, meningioma = 50, vascular disease = 53, other = 31. ICU stay lasted 5.6 +/- 8 d and MV 3.7 +/- 7 d.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1991

[Value of early auditory evoked potentials after neurosurgery].

Recording brainstem auditory evoked potential (BAEP) in post operative period after neurosurgery is easy. The presence of abnormal BAEP predicts unfavorable outcome in both cases with or without sedation. But in case of normal recording it is impossible to predict surely a favorable outcome.

Adult↗
PubMed1991

[Clinical and pharmacokinetic comparative study of sufentanil and fentanyl in supratentorial neurosurgery].

The pharmacokinetic and the effects of sufentanil (S) and fentanyl (F) on cardiovascular stability, brain swelling, respiratory depression and post operative status were studied in 30 neurosurgical patients (group S, n = 15; group F, n = 15). Anesthesia was induced with sufentanil and fentanyl given intravenously (bolus injection 2.5 micrograms.kg-1 vs 25 micrograms.kg-1) followed by a constant rate infusion (0.25 vs 2.5 micrograms.kg-1 x h-1) and a sleep dose of thiopental (3 mg.kg-1) and pancuronium (0.1 mg.kg-1). If necessary, patients could receive more narcotic and, for sudden arousal, a dose of thiopental. Plasma concentrations of sufentanil and fentanyl were measured during and up to 12 hours after infusion. After induction bolus, mean arterial pressure decreased significantly (-30%) with sufentanil. In the group 5, the baseline heart rate and arterial pressure were lower and more stable than in the group F. Brain relaxation always seemed satisfactory. For all but 12 patients with sever neurological status, recovery and extubation times were less than 2 hours and allowed early neurological evaluation. Respiratory depression required naloxone for 2 patients with fentanyl. The plasma clearance of sufentanil and fentanyl (902 vs 914 ml.min-1) are similar. The volumes of distribution are respectively 4.9 and 11.3 l.kg-1, and the half-life 250 and 562 min. The wider volume of distribution and the great half-life compared with previous studies are attributed to corticoïd, osmotic and diuretic preoperative treatment.

Adult↗
PubMed1990

[Preoperative treatment of arterial spasm and preparation of the patient for surgery of intracranial aneurysm].

In spite of various clinical status and timing in surgical treatment of ruptured intracranial aneurysm, some general rules can be put in practice at the preoperative period. Rebleeding prevention by sedation and bedrest seems better than antifibrinolytic therapy which can induce delayed ischemic syndrome and/or hydrocephalus. Most important of treatment regimen appears to be a good hemodynamic stability with hypervolemic hemodilution and hydroelectrolytic control for compensating hyponatremia. Calcium blockers precociously given can be discussed in case of high ICP.

Antifibrinolytic Agents↗
PubMed1990

[Value of cerebral blood flow study with nimodipine test in intracranial aneurysm].

The study of cerebral blood flow (DSC) in 29 patients with intracranial aneurysm is interesting to diagnose cerebral ischemia without clinical and radiological effect. A test with nimodipine sensitize this exam, confirm the efficacy of this drug in located ischemias. But may reveal a decrease of cerebral blood flow after nimodipine: it is probably an interesting therapeutic test.

Adolescent↗
PubMed1989

[Effects of an intravenous injection of nicardipine on cerebral blood flow in subarachnoid hemorrhage caused by intracranial aneurysm].

Fifteen patients with ruptured intracranial aneurysm have been operated before undergoing post surgery xenon inhalation for cerebral blood flow valuation: first measurement has been performed as CBF reference; 2nd measurement has been done after 0.1 mg.kg-1 I.V. bolus of nicardipine; sides effects are mainly due to BP fall 2/15 and some consequent neurological distress have been noticed (2/15); results should be carefully interpreted. Significant CBF increase have been measured after nicardipine injection, specially in brain area correlated to low CBF before injection (the lower the CBF, the higher the increase of local flow). The study prompt us to check the effect of nicardipine on patient (with CBF measurement after nicardipine test) before giving the treatment. Problems remain to be solved with further studies and not yet established: correlation between hemodynamics changes and clinical status and also which time of disease evolution is the best to be treated.

Adult↗