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P Coriat

Publications and source records attributed to P Coriat.

At least 19 recordsLinked to original sources
PubMed2006

Effects of a loading dose of morphine before i.v. morphine titration for postoperative pain relief: a randomized, double-blind, placebo-control study.

BACKGROUND: I.V. morphine titration (MT) allows adjustment of the dose needed for pain relief in the post-anaesthesia care unit (PACU). However, MT has limitations such as a delay to achieve pain relief. We thus assessed the effect of a fixed intraoperative loading dose of morphine administered before titration. METHODS: One hundred patients who were undergoing major orthopaedic surgery were included in a double-blind, randomized study comparing a loading dose of morphine (0.15 mg kg(-1)) with placebo administered intraoperatively. MT was then administered in the PACU followed by patient-controlled analgesia (PCA) over 24 h. Data are expressed as mean (sd). RESULTS: The initial VAS [41 (36) vs 52 (35), NS] was not decreased in the morphine group. The VAS was lower in the morphine group in the PACU and PCA periods. The time to achieve effective pain relief was not decreased in the morphine group. The total dose of morphine administered in the PACU (including the loading dose) was significantly increased in the morphine group (+31% in mg kg(-1), P<0.05). Morphine requirements during the PCA period were not different between groups. The incidence of sedation was increased and a severe episode of ventilatory depression occurred in the morphine group. CONCLUSIONS: A loading dose of morphine administered at the end of surgery slightly decreased the VAS but did not reduce the time to pain relief or morphine consumption within the first 24 h. This slight improvement in analgesia was obtained at the expense of morphine-related adverse events.

Adolescent↗
PubMed2006

Comparison of stroke volume (SV) and stroke volume respiratory variation (SVV) measured by the axillary artery pulse-contour method and by aortic Doppler echocardiography in patients undergoing aortic surgery.

BACKGROUND: The goal of the study was to compare stroke volume (SV) and respiratory stroke volume variation (SVV) measured by pulse-contour analysis and aortic Doppler. METHODS: These were measured by pulse-contour analysis and thermodilution (PiCCO) and by aortic pulsed wave Doppler with transoesophageal echocardiography in patients undergoing abdominal aortic surgery. Simultaneous measurements were done at different times of surgery. All data were recorded on PiCCOwin software and videotape and analysed off-line by a blinded investigator. RESULTS: A total of 114 measurements were achieved in 20 patients. There was a good correlation and small bias between the PiCCO and the echo-Doppler values of the mean SV [r=0.885; bias=0.2 (8) ml], and between the minimum [r=0.842; bias=1 (9) ml] and maximum SV [r=0.840; bias=2 (10) ml] values. CONCLUSIONS: There is a fair correlation between pulse-contour analysis and aortic Doppler for beat-by-beat measurement of SV but not for calculation of SV respiratory ventilation.

Aorta, Abdominal↗
PubMed2006

Low negative predictive value of dobutamine stress echocardiography before abdominal aortic surgery.

BACKGROUND: According to previous studies, a negative dobutamine stress echocardiography (DSE) test before major vascular surgery indicates that postoperative myocardial necrosis is very unlikely. We believe that the use of new cardiac troponin assays which can detect small amounts of myocardial necrosis results in a lower DSE negative predictive value for myocardial necrosis. METHODS: A total of 418 consecutive patients were screened using the ACC/AHA Guideline for Perioperative Cardiovascular Evaluation for Noncardiac Surgery before scheduled abdominal aortic surgery. Of these 143 met ACC/AHA criteria for non-invasive testing and underwent DSE. Patients with a negative DSE were deemed to be fit for surgery. A positive DSE led to a coronary angiogram. DSE was negative in 110 (77%) and positive in 33 (23%) patients. Myocardial necrosis was monitored up to the third postoperative day by daily cardiac troponin I (cTnI) measurement and a daily 12-lead ECG. RESULTS: Coronary angiography showed artery stenosis in 27 (84%) of 32 patients with a positive DSE. The negative predictive value of DSE for cTnI elevation was 92.7% (95% CI 86.2-96.8%). This was significantly lower than the lowest value of negative predictive value for myocardial necrosis assessed in previous studies. CONCLUSION: A negative DSE prescribed before scheduled aortic surgery according to ACC/AHA guidelines does not rule out postoperative myocardial necrosis.

Adult↗
PubMed2005

Risk factors for neurosurgical site infections after craniotomy: a critical reappraisal of antibiotic prophylaxis on 4,578 patients.

The objective of this study was to evaluate incidence and risk factors of postoperative infections, with emphasis on antibiotic prophylaxis, in a series of 4578 craniotomies. A prospective database was implemented for surveillance of postcraniotomy infections. During period A, no antibiotic prophylaxis was prescribed for scheduled, clean craniotomies, lasting less than 4 h, whereas emergency, clean-contaminated or long-lasting craniotomies received cloxacillin or amoxicillin-clavulanate. During period B, prophylaxis was given to every craniotomy. The effect of prophylaxis on craniotomy infections, independently of other risk factors, was studied by multivariate analysis. The overall infection rate was 6.6%. CSF leak, male gender, surgical diagnosis, surgeon, early re-operation, surgical duration and absence of prophylaxis were independent risk factors. CSF leak had the highest odds ratio. Antibiotic prophylaxis decreased infection rate from 9.7% down to 5.8% in the entire population (p<0.0001) mainly by decreasing rates in low risk patients from 10.0% down to 4.6% (p<0.0001). Antibiotic prophylaxis in craniotomy is effective in preventing surgical site infections even in low-risk patients.

Adult↗
PubMed2004

The relationship of intracranial pressure Lundberg waves to electroencephalograph fluctuations in patients with severe head trauma.

Lundberg (or B) waves, defined as repetitive changes in intracranial pressure (ICP) occurring at frequencies of 0.5 to 2 waves/min, have been attributed to cerebral blood flow fluctuations induced by central nervous system pace-makers or cerebral pressure autoregulation. We prospectively recorded and digitalized at a frequency rate of 10 Hz (AcqKnowledge software) the following parameters in 6 brain injured patients: mean arterial pressure, heart rate, ICP, mean flow velocity of the middle cerebral artery (MFVMCA) (transcranial Doppler WAKI) and left and right spectral edge frequency (SEFl, SEFr) of continuous electroencephalogram (EEG) recordings (Philips technologies). All patients were sedated using a combination of sufentanil and midazolam and mechanically ventilated. Cerebral electrical activity (oscillations of SEF at a mean frequency of 26+/-9 mHz) and MFVMCA fluctuations were found strongly correlated with the intracranial Lundberg B waves (mean frequency 23+/-7 mHz). These result support the existence of a neuropacemaker at the origin of the Lundberg B waves. The change in cerebral electrical activity, resulting from cerebral pacemakers, could increase cerebral metabolic rate of oxygen (CMRO2) and thus lead to an increase in cerebral blood flow and secondarily of ICP through a change in cerebral blood volume.

Action Potentials↗
PubMed2004

Anaesthesia for carotid endarterectomy: comparison of hypnotic- and opioid-based techniques.

BACKGROUND: Although the synergistic interaction between hypnotics and opioids for total i.v. anaesthesia has been repeatedly demonstrated, questions about different dose combinations of hypnotics and opioids remain. The optimal combination would be based on maximal synergy, using the lowest dose of both drugs and having the lowest incidence of side-effects. METHODS: The major goal of this prospective randomized study was to compare two different dose combinations of propofol and remifentanil (both administered by target controlled infusion (TCI)) in respect of haemodynamics during surgery and recovery, and the need for cardiovascular treatment in the recovery room. A secondary goal was to compare pain scores (VAS) and morphine consumption in the recovery room. Anaesthesia was induced in both groups using TCI propofol, adjusted to obtain a bispectral index score (BIS) value between 40 and 60. TCI for remifentanil commenced at an initial effect-site concentration of 0.5 ng ml(-1), and was adjusted according to haemodynamics. Patients were divided into one of two groups during anaesthesia: (i). Group H, hypnotic anaesthesia (n=23), propofol effect-site concentration maintained at 2.4 microg x ml(-1); and (ii). Group O, opioid anaesthesia (n=23), propofol effect-site concentration maintained at 1.2 microg x ml(-1). In both groups, remifentanil effect-site concentration was adjusted according to haemodynamics and changes in BIS value. RESULTS: In Group O, more episodes of intraoperative hypotension (P<0.02) and hypertension (P<0.01), and fewer episodes of tachycardia were observed. More patients in Group O required nicardipine administration for postoperative hypertension (8 patients in Group H vs 15 patients in Group O, P<0.04). During recovery, morphine titration was necessary in approximately 50% of patients. No significant difference between groups was observed concerning pain scores or requirement for morphine titration. CONCLUSIONS: Maintenance of anaesthesia predominantly with propofol and a low dose of remifentanil, both administered using TCI, is associated with greater stability in perioperative haemodynamics than anaesthesia predominantly with remifentanil alone. Postoperative pain was identical in both groups of patients who underwent relatively short duration, and relatively painless surgery.

Aged↗
PubMed2003

[Identification of risk factors for allogenic transfusion in cardiac surgery from an observational study].

OBJECTIVE: To determine perioperative variables for predicting allogenic transfusion in adult cardiac surgery. STUDY DESIGN: Prospective study. PATIENTS: We included 335 consecutive patients undergoing cardiac surgery between February and April 2001. METHODS: Perioperative variables were prospectively collected in a database. For each patient who received transfusion, hemoglobin threshold for transfusion and total number of units of red cell concentrates were collected. Univariate and multivariate analysis were performed. RESULTS: The two strategies for blood conservation which were predominantly used were aprotinin therapy (78%) and blood salvage from the extracorporeal circuit (68%). During perioperative period, 42% of patients [95% CI: 37-47%] received allogenic transfusion. The haemoglobin threshold for transfusion was 7.4 +/- 1.1 and 8.0 +/- 0.7 g x dl(-1) in operating room and in intensive care unit, respectively. On average, 3.4 +/- 2.7 units of red cell concentrates were transfused perioperatively per patient. Using multivariate analysis, perioperative allogenic transfusion was significantly associated with the following variables: preoperative haemoglobin level < 12 g x dl(-1) (odds ratio 8.9; p = 0.001), emergency procedure (odds = 3.7, p = 0.01), reoperation (odds ratio = 3.3; p = 0.002), chronic obstructive pulmonary disease (odds ratio = 2.5; p = 0.03) and complex surgery (odds ratio = 2.4; p = 0.01). The age, the gender, and body mass index were only independent risk factors by univariate analysis. CONCLUSION: In despite of techniques to limit requirement of allogenic transfusion, a large proportion of cardiac surgical patients remains transfused. Independent risk factors of perioperative transfusion are haemoglobin level < 12 g x dl(-1), emergency procedure, reoperation, chronic obstructive pulmonary disease and complex surgery.

Adult↗
PubMed2003

[Subdural haemorrhage following lumbar spinal drainage during repair of thoraco-abdominal aneurysm].

Physicians in charge of patients undergoing thoracic or thoraco-abdominal aneurysmectomy, frequently use lumbar spinal drainage of the cerebrospinal fluid (CSF) to prevent paraplegia. Whereas the profit of this technique is a much debated question, we report 2 case reports of delayed sub-dural hemorrhage, after lumbar spinal drainage of CSF. Cross clamping of the aorta decreases the spinal cord artery pressure, increases the cerebral pressure and by alterations of distribution of the venous return, is responsible for an increase of the CSF pressure. This increase of the CSF pressure decreases the spinal cord driving pressure. Lumbar spinal drainage of CSF aims to improve the spinal cord driving pressure close to the normal (where driving pressure = aortic pressure - CSF pressure). The two case reports have to be added to the liability of a method of prevention that, as attractive that it is, did not give the proof of its efficiency to decrease the frequency and/or the severity of paraplegia after thoracic or thoraco-abdominal aneurysmectomy. At this time, this technique should be reserved to the patients with documented risk, as it is possible using preoperative spinal cord arteriography. The insertion and the withdrawal of the catheter must be done in the usual conditions of medullar puncture with regard to anticoagulant and antiplatelet agents

Aged↗
PubMed2003

What pain scales do nurses use in the postanaesthesia care unit?

BACKGROUND AND OBJECTIVE: The visual analogue scale (VAS) is considered as the gold standard method for postoperative pain assessment. Nevertheless, in some clinical situations, this method may not be reliable. We performed an observational study to assess the use of the VAS and other pain scales by nurses in the postanaesthesia care unit. METHODS: We studied the reasons for not using the VAS and asked if it may be less appropriate in certain age groups. RESULTS: Among 600 patients included in the study (16% = 70 yr), nurses used the VAS in 53%, the numerical rating scale in 30%, the verbal rating scale in 12% and the behavioural scale in 5%. In 43% of the assessments, nursed did not use the VAS; the most frequently cited reason was related to their preference for other methods. In 54% of the assessments, the reason for not using the VAS was related to the patients, mainly when they were in too much pain to use it (22%). When the patient was in too much pain, the numerical rating scale was chosen in 54% and the behavioural scale in 27%. There was no difference between young patients and elderly patients. CONCLUSIONS: Although the VAS is the standard method to assess pain, the nurses preferred using the numerical rating scale, both spontaneously or when VAS assessment was not possible.

Adolescent↗
PubMed2003

Adjunctive analgesia with intravenous propacetamol does not reduce morphine-related adverse effects.

BACKGROUND: Propacetamol is widely used in the management of postoperative pain. It decreases morphine requirements but its effect on the incidence of morphine-related adverse effects remains unknown. METHODS: Patients (550) were randomly assigned to receive propacetamol or a placebo over the first 24 h after operation in a blinded study. Intravenous morphine titration was performed, after which morphine was administered s.c. every 4 h according to their pain score. Pain was assessed using a visual analogue scale (VAS). The primary end-point was the incidence of morphine-related adverse effects. The main secondary end-points were morphine requirements and VAS score. RESULTS: After morphine titration, the VAS score and the number of patients with pain relief did not differ between groups. Morphine requirements were decreased in the propacetamol group (21 vs 14.5 mg, P<0.001) but the incidence of morphine-related adverse effects did not differ between groups (42 vs 46%, not significant). In patients with moderate pain (n=395), morphine requirements decreased by 37% (P<0.001) and the percentage of patients requiring no morphine was greater (21 vs 8%, P=0.002) in the propacetamol group. In patients with severe pain (n=155), morphine requirements decreased by 18% (P=0.04) in the propacetamol group and the number of patients who did not require morphine (3 vs 8%) did not differ significantly. CONCLUSIONS: Although propacetamol induced a small morphine-sparing effect, it did not change the incidence of morphine-related adverse effects in the postoperative period. Moreover, no benefit could be demonstrated in patients with severe postoperative pain.

Acetaminophen↗
PubMed2003

Target-controlled infusion of propofol and remifentanil in cardiac anaesthesia: influence of age on predicted effect-site concentrations.

BACKGROUND: Propofol-anaesthesia administrated via target-controlled infusion (TCI) has been proposed for cardiac surgery. Age-related changes in pharmacology explain why propofol dose requirement is reduced in elderly patients. However, the Marsh pharmacokinetic model incorporated in the Diprifusor propofol device does not take age into account as a covariable. In the absence of depth of anaesthesia monitoring, this limitation could cause adverse cardiovascular effects resulting from propofol overdose in older patients. We assessed the influence of age on effect-site propofol concentrations predicted by the Diprifusor and titrated to the bispectral index score (BIS) during cardiac anaesthesia. METHODS: Forty-five patients received propofol by Diprifusor and remifentanil by software including Minto model. Propofol and remifentanil effect-site concentrations were adapted to BIS (40-60) and haemodynamic profile, respectively. The influence of age on effect-site concentrations was assessed by dividing patients into two groups: young (<65 yr) and elderly (> or =65 yr). RESULTS: For a similar depth of anaesthesia, effect-site propofol concentrations were significantly lower in elderly patients at the different stages of cardiac surgery. The mean dose of propofol required to perform tracheal intubation was significantly lower in elderly patients. However, the overall doses of propofol were comparable in both groups. Neither effect-site remifentanil concentrations nor overall doses of remifentanil were significantly different between the two groups. CONCLUSIONS: In cardiac anaesthesia, target concentrations of propofol must be reduced in elderly patients. Although this probably contributes to improving intraoperative haemodynamic stability, the absence of decrease in overall dose requirement of propofol suggests that this adjustment is relatively moderate.

Adolescent↗
PubMed2003

Effects of halogenated anaesthetics on diaphragmatic actin-myosin cross-bridge kinetics.

BACKGROUND: The effects of halogenated anaesthetics on cross-bridge (CB) kinetics are unclear. As halogenated anaesthetics do not markedly modify the intracellular calcium transient in the diaphragm, we used an isolated rat diaphragm preparation to assess the effects of halothane and isoflurane on CB kinetics. METHODS: The effects of halothane and isoflurane (1 and 2 minimum alveolar concentration (MAC)) on rat diaphragm muscle strips were studied in vitro (Krebs-Henseleit solution, 29 degrees C, oxygen 95%/carbon dioxide 5%) in tetanus mode (50 Hz). From the force-velocity curve and using A. F. Huxley's equations, we determined the main mechanical and energetic variables and calculated CB kinetics. RESULTS: At 1 and 2 MAC, isoflurane and halothane induced no significant inotropic effects. Whatever the concentrations tested, halothane and isoflurane did not significantly modify the CB number, the elementary force per CB, the attachment and detachment constants, the duration of the CB cycle and mean CB velocity. CONCLUSION: In the rat diaphragm at therapeutic concentrations, halogenated anaesthetics do not significantly modify CB mechanical and kinetic properties.

Actins↗
PubMed2003

The phenomenology of body image distortions induced by regional anaesthesia.

Patients with peripheral nerve or spinal cord lesions frequently report perceptual distortions related to position, shape, texture or temperature of the affected areas. This study aimed to describe the phenomenology of such body image alterations during the course of upper limb, lower limb or spinal anaesthetic blocks in patients (n = 36) undergoing orthopaedic surgery. Multimodal sensory testing and assessment of motor function were performed at regular intervals, and the relationship between the reported body image distortions and the progression of sensory and motor impairment was analysed. We found that perceptual changes concerning the shape and size of the deafferented limb occurred in the great majority of patients. In all of them, illusions of swelling, elongation or shortening of the limb coincided with the impairment of warm, cold and/or pinprick sensations, suggesting that thin myelinated Adelta- and/or unmyelinated C-fibres may provide a source of tonic modulation to the limb's cortical representation. Such perceptual alterations of shape and size of body parts differed clearly from postural illusions in terms of frequency, time course and influence of vision. In addition to perceptual changes in the deafferented area, almost half of the patients felt their unanaesthetized lips and/or mouth swelling during the course of upper limb block, suggesting the unmasking of dynamic interactions between somatotopically adjacent cortical representations. Conflicting sensations could co-exist in the patient's body image, such as the illusion of swelling of a limb, which, at the same time, was felt to be missing. The sense of ownership of the deafferented limb was impaired in some cases. These observations show that the perception of body shape and the awareness of its postural variations are built from different plastic models. They also underline the contribution of peripheral afferent activity to the maintenance of a unified body image.

Adolescent↗
PubMed2002

Empirical treatment of adult postsurgical nosocomial meningitis.

BACKGROUND: The combination of cefotaxime and fosfomycin (CTX-FOS) has been proposed in France for the empirical treatment of postoperative nosocomial meningitis since the late 1980s. The purpose of this work was to evaluate this strategy today, as well as other possible treatments. METHODS: Each patient undergoing a neurosurgical procedure was prospectively included in a database designed for the surveillance of surgical site infection (SSI). For each meningitis detected, we analysed the in vitro susceptibility of the causative micro-organisms to cefotaxime alone (CTX), cefotaxime-fosfomycin (CTX-FOS), vancomycin (VAN) and cefotaxime-vancomycin (CTX-VAN) combinations. The patient population was divided into two groups according to the presence or absence of CSF shunting material. FINDINGS: 116 patients had had a postoperative meningitis/ventriculitis during the last 36 months, among 6447 patients undergoing neurosurgery in our department (1.8%). Ten patients had aseptic meningitis (8.6%). Overall sensitivity to CTX was 69.8%, as compared to 77.3% with CTX-FOS combination (NS). This result was due to a large proportion of fosfomycin resistant cocci in our population. The CTX-VAN combination increased the overall in vitro susceptibility up to 91.5%, but the benefit of this combination was only significant in CSF shunting material patients. In these latter patients, VAN was as effective as CTX-FOS combination. INTERPRETATION: CTX-FOS combination is no longer the best choice for empirical treatment of post neurosurgical meningitis. CTX alone can be safely used in patients without a CSF shunt; in those with either a ventriculostomy or a CSF shunt associated ventriculitis, a CTX-VAN combination could improve treatment efficacy, provided that high doses of vancomycin are used to ensure correct CSF diffusion.

Adult↗