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X Capdevila

Publications and source records attributed to X Capdevila.

31 records · Page 2Linked to original sources

[Continuous analgesia with a femoral catheter: plexus or femoral block?].

OBJECTIVE: To evaluate the spread and quality of sensitive blockade produced by continuous and prolonged use of a femoral catheter inserted for postoperative analgesia. STUDY DESIGN: Prospective non comparative evaluation. PATIENTS: The study included 20 consecutive patients undergoing major knee surgery with postoperative analgesia obtained with a femoral catheter, a technique commonly used in our department. METHODS: Regional analgesia was induced after surgery with a bolus injection of 30 mL of 2% lidocaine with 1:200,000 epinephrine 1 in 200,000, maintained by continuous infusion of 1% lidocaine + morphine 0.03 mg.mL-1 + clonidine 2 micrograms.mL-1 for 48 h. The infusion rate was 0.1 mL.kg-1.h-1. The evaluation was based on: 1) the quality of analgesia at rest, at 30 min, h1, h3, h6, h12, h24 and h48; 2) the sensitive and motor blockade at the same time intervals. RESULTS: A "3 in 1" block was only observed in 50% of patients after the initial bolus via the femoral catheter. During the maintenance of analgesia with a continuous infusion a blockade of the three main nerves of the lumbar plexus occurred in less than 20% of patients after 6 h and was limited to the territory of the femoral nerve in 45 to 50% of patients after 12 to 48 h. In all cases the median values of VAS were below 42 mm. CONCLUSION: In most patients, a local anaesthetic administered continuously via a femoral catheter produces a blockade limited to the femoral nerve. These data do not substantiate the conclusions by those who consider they are producing a continuous "3 in 1" block with this technique. However, it is obviously not essential to produce a sensitive blockade of the three main nerves of the lumbar plexus to obtain an effective analgesia after knee surgery.

Adult↗

Bilateral continuous 3-in-1 nerve blockade for postoperative pain relief after bilateral femoral shaft surgery.

We tested the effectiveness of bilateral continuous paravascular femoral nerve blocks in a patient following bilateral femoral shaft surgery in whom other analgesic regimens were considered contraindicated or of limited effectiveness. Bilateral continuous femoral paravascular nerve blocks were performed using a previously described technique. General anesthesia was subsequently used to facilitate surgery, which was a bilateral osteosynthesis using dynamic hip screws for osteolytic metastases of the proximal extremities of both femurs. A continuous infusion of lidocaine, morphine, and clonidine was established in both femoral catheters preoperatively and used postoperatively as the principle source of analgesia. Radiographic contrast was used to document the position of both catheters and to document the spread of injectate. Visual analog scale (VAS) pain scores were recorded in the recovery room and at 4, 16, 24, 48, and 72 hours postoperatively. Plasma lidocaine levels were determined by gas chromatography at 4, 16, and 48 hours postoperatively. Sensory assessment in the distribution of the femoral, lateral cutaneous, and obturator nerves was performed to confirm the presence of sensory blockade. We successfully provided analgesia with bilateral continuous femoral paravascular nerve blocks. Pain scores at rest were consistently rated good to excellent (VAS < 20 mm). Evidence of sensory conduction block was present throughout the infusion. Plasma concentrations of lidocaine were consistently below toxic levels (1.35 to 1.65 micrograms/ml). Radiographic contrast studies failed to demonstrate movement of contrast to the level of the lumbar plexus. Bilateral continuous femoral paravascular nerve blocks can be used to provide effective and safe analgesia in patients requiring aggressive analgesia in whom other techniques may be contraindicated.

Anesthetics, Local↗

Tension-time index of inspiratory muscles in COPD patients: role of airway obstruction.

Inspiratory muscle function has been shown to be related to general muscle weakness, weight loss, blood gas tensions, airway obstruction and hyperinflation. The aim of this study was to define (1) the factor that is the main determinant of the tension-time index of the inspiratory muscles (TTmus), and which this increases the risk of inspiratory muscle fatigue; and (2) whether a breathing strategy is adopted to avoid inspiratory muscle fatigue. Twenty-seven normal volunteers and 35 stable COPD outpatients (FEV1% predicted, range: 21-89%; and FRC/TLC, range: 49-77%) were studied. The TTmus was determined as follows: TTmus = PI/PImax.TI/Ttot, where Pi is the mean inspiratory pressure calculated from the mouth occlusion pressure (P0.1), PImax is the maximal inspiratory pressure, TI is the inspiratory time, and Ttot is the total time of the breathing cycle. COPD patients showed significantly lower PImax and higher P0.1, PI, PI/PImax, and TTmus than normal subjects. No patient had a TTmus value higher than the inspiratory muscle fatigue threshold of 0.33. The FEV1 was significantly correlated with TTmus and all its components in the patients. The FRC/TLC was also correlated with all components except PI. Body weight was only correlated with PImax. In a forward and backward stepwise regression analysis, FEV1 appeared to be the only significant factor explaining the variance of log (PI/PImax) and log (TTmus), whereas FRC/TLC was the principal determinant of PImax. In COPD patients, a non-linear relationship was found between TI and P0.1. A negative linear relationship was found between TI/Ttot and PI/PImax. In conclusion, although hyperinflation predominantly affected inspiratory muscle strength in a group of stable COPD patients with a wide range of severity, airway obstruction was the principal factor determining the magnitude of TTmus. In addition, in order to remain below the inspiratory muscle fatigue threshold, as the severity of airway obstruction increased, patients adopted a breathing strategy characterized by decreased TI/Ttot as inspiratory pressure demand increased.

Adaptation, Physiological↗

The effects of cervical epidural anesthesia with bupivacaine on pulmonary function in conscious patients.

UNLABELLED: Cervical epidural anesthesia (CEA) can affect diaphragmatic function. We investigated the effects of CEA on the diaphragm muscle performance, breathing pattern, and respiratory drive of 10 healthy patients undergoing hand surgery before and after the administration of 0.25% and 0.375% bupivacaine. The lung volumes and flows, respiratory rate (RR), minute ventilation, respiratory cycle time, occlusion pressure, maximal inspiratory pressure (MIP), and hand grip strength were determined. ETCO2 and SpO2 were continuously monitored. The diaphragmatic excursion was evaluated using ultrasonography. Although CEA allowed painless hand rehabilitation, both 0.25% and 0.375% bupivacaine impaired diaphragmatic excursion, with values decreasing from 5.6 to 4.4 and 3.3 cm (P < 0.05), respectively, during forced sniff maneuvers. In the 0.25% and 0.375% bupivacaine groups, the values of MIP decreased from 74 to 56 and 44 cm H2O, forced vital capacity decreased from 3.8 to 3.2 and 2.8 L, and hand grip strength decreased from 43.3 to 27.8 and 20.5 kg force, respectively (P < 0.05). The tidal volume decreased from 0.8 to 0.6 and 0.5 L in the 0.25% and 0.375% bupivacaine groups, respectively, the RR increased from 14 to 18 breaths/min in both groups, and the occlusion pressure increased from 1.5 to 2.1 and 2.9 cm H2O in the 0.25% and 0.375% bupivacaine groups, respectively (P < 0.05). ETCO2 increased from 35.2 to 38.1 and 39.3 mm Hg in the 0.25% and 0.375% bupivacaine groups, respectively, and SpO2 decreased by 2% +/- 1% in the 0.375% bupivacaine group. CEA affects diaphragmatic function and the resulting lung volumes and MIP values. The observed alterations in breathing pattern and the significant increase in ventilatory drive may be caused by changes in the diaphragmatic muscle tension and an augmented CO2 load. In conclusion, we do not recommend this technique for routine postoperative hand rehabilitation using the studied bupivacaine concentrations. IMPLICATIONS: We studied cervical epidural anesthesia in healthy patients undergoing hand surgery. The technique allowed painless rehabilitation but affected breathing pattern, diaphragmatic function, and respiratory drive. We cannot recommend this technique for routine clinical use.

Adult↗

Comparison of the three-in-one and fascia iliaca compartment blocks in adults: clinical and radiographic analysis.

UNLABELLED: The 3-in-1 (Group 1) and fascia iliaca compartment (Group 2) blocks, two single-injection, anterior approach procedures used to simultaneously block the femoral, obturator, and lateral femoral cutaneous (LFC) nerves, were compared in 100 adults after lower limb surgery. Pain control, sensory and motor blockades, and radiographically visualized spread of local anesthetic solution were studied prospectively. Both approaches provided efficient pain control using 30 mL of 2% lidocaine with 1:200,000 epinephrine and 0.5% bupivacaine and 5 mL of contrast media (iopamidol). Complete lumbar plexus blockade was achieved in 18 (38%) Group 1 and 17 (34%) Group 2 patients (n = 50 patients per group). Sensory block of the femoral, obturator, genitofemoral, and LFC nerves was obtained in 90% and 88%, 52% and 38%, 38% and 34%, and 62% and 90% of the patients in Groups 1 and 2, respectively (P < 0.05). Sensory LFC blockade was obtained more rapidly for the patients in Group 2 (P < 0.05). Concurrent internal and external spread of the local anesthetic solution under the fascia iliaca and between the iliacus and psoas muscles was noted in 62 of the 92 block procedures analyzed radiographically. Isolated external spreads under the fascia iliaca and over the iliacus muscle were noted in 10% and 36% of the patients in Groups 1 and 2, respectively (P < 0.05). The local anesthetic solution reached the lumbar plexus in only five radiographs. We conclude that the fascia iliaca compartment block is more effective than the 3-in-1 block in producing simultaneous blockade of the LFC and femoral nerves in adults. After both procedures, blockade was obtained primarily by the spread of local anesthetic under the fascia iliaca and only rarely by contact with the lumbar plexus. IMPLICATIONS: In adults, the two anterior approaches, 3-in-1 and fascia iliaca compartment blocks, provide effective postoperative analgesia. The fascia iliaca compartment technique provides faster and more consistent simultaneous blockade of the lateral femoral cutaneous and femoral nerves. Sensory block is caused by the spread of local anesthetic solution under the fascia iliaca and only rarely to the lumbar plexus.

Adult↗

Aprotinin decreases blood loss and homologous transfusions in patients undergoing major orthopedic surgery.

BACKGROUND: Major orthopedic surgery can be associated with dramatic blood loss, thereby requiring high-volume homologous transfusions in patients unable to benefit from blood salvage techniques. The effect of aprotinin on blood loss and transfusion requirements during orthopedic surgery for either the resection of malignancies of the removal of infected hardware was prospectively studied. METHODS: Twenty-three patients scheduled for orthopedic surgery of the hip, femur, or pelvis for sepsis or malignant tumors, all under general anesthesia, were randomly allocated to receive during operation, in a blinded manner, either aprotinin administered as a bolus of 1.106 kallikrein inactivation units (KIU) followed by an infusion of 5 x 10(5) KIU/h, or the equivalent volume of saline. The anesthesia and perioperative management, as well as the designated transfusion criteria, were standardized. The total blood loss of each patient was evaluated using intraoperative suction losses, sponge weights, and postoperative volumetric drainage. Homologous transfusion requirements were noted. Hemoglobin and hematocrit measures, as well as coagulation and fibrinolytic pathway explorations, were performed before and after surgery. Deep venous thrombosis prophylaxis was applied, and the incidence of this complication was assessed. RESULTS: Twelve patients received aprotinin. Aprotinin reduced the total blood loss from a median of 5,305 ml (range, 3,000-9,770 ml) to a median of 1,783 ml (range, 1,140-4,955 ml; P < 0.05). A blood loss reduction of 56% during surgery and 68% on discharge from the postanesthesia care unit was observed. Seven units (range, 4-16) of packed erythrocytes were transfused per patient in the placebo group, and 3 (range, 2-5) were transfused in the aprotinin group (P < 0.05). In the aprotinin group, platelet counts were higher, and postoperative prothrombin times and D. Dimer values were lower. The activated partial thromboplastin time values showed no significant difference between the two groups. No side effects were observed in the aprotinin group. A deep venous thrombosis developed in one patient in the placebo group. CONCLUSION: Aprotinin treatment during major orthopedic surgery significantly reduces both blood loss and consequent homologous blood transfusion requirements.

Adult↗

Causes and prediction of maldistribution during continuous spinal anesthesia with isobaric or hyperbaric bupivacaine.

BACKGROUND: Many cases of cauda equina syndrome after maldistribution of local anesthetics during continuous spinal anesthesia have been reported. In experiments, a caudad route of catheter travel and the use of hyperbaric agents have been shown to induce these limited blocks. The aim of this clinical study was to verify this hypothesis and seek a predictive factor for the maldistribution of bupivacaine. METHOD: Continuous spinal anesthesia via a 19-gauge end port spinal catheter was performed in 80 elderly patients randomly assigned to receive either isobaric or hyperbaric solutions. Successive injections of 2.5 mg bupivacaine were performed at 5-min intervals until a sensory level at or cranial to T8 was obtained. Maldistribution was defined by a sensory level caudal to T12 despite a total dose of 17.5 mg of either isobaric or hyperbaric bupivacaine. After surgery, all catheters were injected with contrast media and examined radiographically. RESULTS: The frequency of maldistribution was not significantly different in the isobaric and hyperbaric groups. A caudally oriented catheter tip was found to be a major cause of maldistribution (P < 10(-5)). A thoracic sensory level could be reached in all patients presenting a limited block by simply changing the baricity of the bupivacaine, the position of the patient, or both. The sensory level obtained 10 min after the first injection of 2.5 mg isobaric or hyperbaric bupivacaine was found to be a predictive factor of maldistribution. CONCLUSIONS: Hyperbaric solutions do not appear to be a clinical factor in the development of limited block. The principle factor causing the maldistribution of bupivacaine is the caudal orientation of the tip of the end-hole catheter rather than its level or the route of catheter travel.

Aged↗

Changes in breathing pattern and respiratory muscle performance parameters during difficult weaning.

OBJECTIVE: This study examined, using noninvasive means, the changes in breathing pattern and inspiratory muscle pressure-time indices during difficult progressive withdrawal of pressure-support ventilation. DESIGN: A prospective analysis of the temporal evolution of several respiratory variables in difficult-to-wean patients. SETTING: A university hospital intensive care unit. PATIENTS: A heterogeneous group of 17 patients receiving prolonged mechanical ventilation. INTERVENTIONS: Daily measurements of breathing pattern and respiratory muscle performance parameters in difficult-to-wean patients. MEASUREMENTS AND MAIN RESULTS: We examined breathing pattern variables, rapid shallow breathing (respiratory rate/tidal volume), tracheal occlusion pressure, maximal inspiratory pressure (P(I)max), and the tension-time index of the inspiratory muscles (TTmus = P(I)/P(I)max x Ti/Ttot) (where Ti/Ttot is inspiratory fraction of the cycle). All measurements were repeated at 24-hr intervals throughout the difficult weaning period. The patients were extubated on satisfying ten of 12 classical weaning criteria. Eleven patients were successfully weaned from mechanical ventilation while six patients were not. Weaning failure was associated with the following: a) longer periods of mechanical ventilation before weaning; b) high values of tracheal occlusion pressure, respiratory rate, minute ventilation, and effective impedance maintained throughout the difficult weaning period; and c) persistent high PaCO2 and intrinsic positive end-expiratory pressure values. As the weaning failure patients' inspiratory muscles confronted an increasing inspiratory load, values of the tension-time index of the inspiratory muscles entered or remained in the fatigue zone. In contrast, weaning success patients normalized their breathing pattern and decreased their tracheal occlusion pressure, effective impedance, and tension-time index values. CONCLUSIONS: Breathing pattern alterations and respiratory muscle performance impairments lead to ventilator dependency after prolonged mechanical ventilation. The measurement of variables such as the noninvasive tracheal occlusion pressure, inspiratory power of breathing, and tension-time index of the inspiratory muscles facilitate the management of difficult-to-wean patients.

Aged↗

Haemodynamic effects of moderate normovolaemic haemodilution in conscious and anaesthetized patients.

We have assessed the haemodynamic effects of moderate normovolaemic haemodilution in ASA I patients, either conscious or during enflurane-fentanyl anaesthesia (10 patients in each group). Cardiac index (CI), stroke index (SI) and ejection fraction (EF) were measured by transthoracic electrical bioimpedance and, in the anaesthesia group, arterial and central venous blood samples were obtained to assess oxygen delivery (DO2), oxygen consumption (VO2) and oxygen extraction ratio (O2ER). In conscious patients, heart rate (HR) remained unchanged as SI, EF and CI increased. When haemodilution was performed during anaesthesia, CI remained stable in spite of a slight increase in SI, as HR decreased. This produced a reduction in DO2 which was compensated for by an increase in O2ER, allowing maintenance of VO2 without alteration in blood lactate concentration.

Adolescent↗

Bronchoalveolar lavage for diagnosing bacterial pneumonia in mechanically ventilated patients.

To assess the usefulness of BAL in diagnosing bacterial pneumonia in mechanically ventilated patients, 80 BAL fluid samples obtained from 72 patients with lung infiltrates were studied using the following parameters: infected cell count (polymorphonuclear leukocytes or macrophages with intracellular organisms), microscopic examination of stained smears, and quantitative culture with the determination of the simplified bacterial index (SBI) and the predominant species index (PSI). Of the 80 BAL samples studied, 56 were performed under antibiotic therapy. Bacterial pneumonia was the final diagnosis in 28 cases. The SBI is the sum of the whole numbers of each bacterial concentration expressed as a common logarithm. The PSI is the whole number of the predominant microorganism's concentration expressed as a common logarithm. The discriminative value of each test was assessed using a receiver operating characteristic (ROC) curve, whereby the possibility of establishing a cutoff value used to discriminate between the presence or absence of pneumonia is evaluated. The percentage of infected cells was higher in the pneumonia group (8.8 +/- 18.1 versus 0.4 +/- 1.1%, p < 10(-3), but no cutoff value could be proposed. Under microscopic examination, the presence of bacteria was noted with a significantly greater frequency in the pneumonia group (sensitivity 67.8% and specificity 82.7%). A total of 58 BAL samples were positive when cultured. The SBI was significantly higher in the pneumonia group (6.5 +/- 2.9 versus 1.6 +/- 1.7, p < 10(-4).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Hemodynamic effects of 0.375% versus 0.25% bupivacaine during cervical epidural anesthesia for hand surgery.

BACKGROUND AND OBJECTIVES: Cervical epidural anesthesia with 0.375% or 0.25% bupivacaine plus fentanyl is a reliable technique for surgical restoration of digital motion-after tourniquet release and rehabilitation. The study was designed to assess the hemodynamic effects of this technique in 11 ASA 1 patients. METHODS: The epidural catheter was introduced at the C7-T1 interspace on the day of operation. The volume of 0.375% bupivacaine necessary to block the brachial dermatomes was determined. The day after (day 1), every patient received epidurally the determined volume of 0.375% bupivacaine plus 1 microgram/kg fentanyl (group A). On day 2 the same volume of 0.25% bupivacaine plus 1 microgram/kg fentanyl (group B) was injected. For each patient one or several pairs of injection (A + B) were performed in relation with duration of rehabilitation. Cardiac index, stroke volume index, end diastolic index, ejection fraction, and systemic vascular resistance were studied by thoracic electrical bioimpedance. These parameters, mean arterial pressure and heart rate were recorded before and after injection. Sensory level was assessed by loss of cold sensation. RESULTS: Nineteen paired injections were performed. Mean volume of bupivacaine was 7.1 +/- 2 mL. The caudad sensory level was lower in group A: T7 (T3-L1) versus T6 (T2-T11) in group B. Hemodynamic variables were not different between the 2 groups. Mean arterial pressure cardiac index, heart rate, stroke volume index, and ejection fracture decreased slightly as end diastolic index remained unchanged and systemic vascular resistance increased slightly. No correlation was found between hemodynamic changes and spread of analgesia. CONCLUSIONS: Hemodynamic effects, in ASA 1 patients, are moderate and not dependent on the studied concentration of bupivacaine, indicating that a similar degree of sympathetic block is achieved with 0.375% and 0.25% bupivacaine.

Adult↗