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N Fàbregas

Publications and source records attributed to N Fàbregas.

14 recordsLinked to original sources
PubMed2004

[Preoperative adverse events during stereotactic microelectrode-guided deep brain surgery in Parkinson's disease].

OBJECTIVES: To evaluate the prevalence of adverse events and complications during surgery using deep brain electrodes, mainly in the treatment of Parkinsonism. To describe the adjustment of propofol to meet the needs of neurophysiological monitoring. PATIENTS AND METHODS: A prospective study of patients undergoing stereotactic microelectrode-guided deep brain surgery (stereotactic pallidotomy, implantation of electrodes in the thalamic or subthalamic neurons of the globus pallidus). After placement of a stereotactic frame and completion of a computed tomography scan of the head, the patients were transferred to the operating room. Monitoring included electrocardiography, pulse oximetry, arterial pressure (invasive), endtidal carbon dioxide pressure, and diuresis. Anesthesia was maintained by intermittent infusion of propofol. Variables recorded were age, sex, disease and time elapsed since diagnosis, surgical complications and their treatment, total dose of propofol, duration of surgery, and place of transfer for recovery. RESULTS: One hundred twenty-eight patients (50 women, 78 men) with a mean (+/- SD) age of 59.6 +/- 10.2 years underwent the procedure from 1996 through 2003. The mean time elapsed since diagnosis of the disease was 14 +/- 6.2 years. The propofol dose was 890.6 +/- 571.4 mg and duration of surgery was 8.3 +/- 2.4 hours. Adverse events were observed for 101 patients (78.9%). The most common complications involved hemodynamics: arterial hypertension (59.4%), bradycardia (18.0%), arterial hypotension (7.9%), and tachycardia (6.2%). Other more serious complications were pneumocephalus with clinical repercussions (3 cases), globus pallidus hematoma (2), air embolism (2), epileptic seizure (3), anisocoria (1), and dyspnea and/or airway obstruction (7). CONCLUSIONS: Deep brain stimulation requires surgery of long duration. Because of frequent episodes of arterial hypertension, which increases the risk of brain hemorrhage, and other less common but potentially dangerous complications, careful clinical monitoring is necessary during the procedure. The intermittent use of propofol does not interfere with neurophysiological monitoring.

Aged↗
PubMed2002

Pulmonary infection in the brain injured patient.

Incidence of ventilator associated pneumonia (VAP) in brain injury patient ranges from 28 to 40 %. Brain injury may induce immunosuppression explaining why neurotraumapatients are at higher risk of developing early onset pneumonia. However, occurrence of pneumonia in brain injury patient has not been associated to higher mortality. Many methods such as selective digestive decontamination, early administration of antibiotics, continuous subglottic aspiration, improved initial choice and dosage of antibiotic, may be useful to prevent and treat VAP in brain injury.

Brain Injuries↗
PubMed2001

Monitoring in neuroanaesthesia: update of clinical usefulness.

The aim of specific monitoring in neuroanaesthesia is to detect, as quickly as possible, intraoperative ischaemic insults so that the brain and the spinal cord may be protected from harmful and frequently inevitable events due to the type of surgery, patient positioning, haemodynamic changes or any intercurrent event. New monitors are being introduced into the operating theatre, but only a few are considered to be an absolute standard of care in neurosurgery, e.g. facial nerve monitoring for surgery of acoustic neuromas and recording of evoked potentials during repair of scoliosis. In the past decade, new monitoring devices have moved from the experimental stage to the operating theatre and although most are still in a phase of technological development and/or definition of their field of applicability they are being used as guides for clinical practice in those instances where cerebral well-being might be impaired. The metabolic consequences of hyperventilation, pharmacological electroencephalogram burst suppression, hypothermia, etc. can now be assessed in the operating theatre. Non-invasive monitoring is being rapidly integrated into our daily work because of its lack of secondary effects. Nevertheless, each new development is regarded as an addition rather than as a substitute for existing equipment. The perfect combination of monitors to provide essential information during an individual surgical procedure to influence a better patient outcome, is still uncertain and needs extensive clinical research.

Anesthesia↗
PubMed2001

Episodic high irrigation pressure during surgical neuroendoscopy may cause intermittent intracranial circulatory insufficiency.

Intermittent high peak pressure values inside the endoscope during neuroendoscopic surgical procedures are associated with postoperative morbidity. Unexpected delay in awakening is the complication most frequently observed by the anesthesiologist as a result of high peak pressure values inside the endoscope. During eight neuroendoscopic procedures the authors continuously monitored cerebral hemodynamic function, using a transcranial doppler (TCD) probe fixed on patients' temporal window. We observed that episodes of high peak pressure values inside the endoscope during neuroendoscopic navigation rinsing periods resulted in changes in the TCD wave profile consistent with "near intracranial circulatory arrestlike" wave. No systemic hemodynamic warning signs accompanied these intermittent episodes of severe decrease in cerebral perfusion pressure. When the rinsing liquid was allowed to escape, the pressure inside the endoscope decreased and the TCD wave immediately returned to its previous value. Neuroendoscopic procedures, although classified as minimally invasive surgery, warrant special monitoring that could alert us to a decrease in cerebral perfusion pressure. Middle cerebral artery TCD recording is a reliable and accurate tool for this purpose.

Adult↗
PubMed2000

Sampling methods for ventilator-associated pneumonia: validation using different histologic and microbiological references.

OBJECTIVE: To validate sampling techniques (tracheobronchial aspirates, protected specimen brush, and bronchoalveolar lavage, both conventional and protected) for the detection of ventilator-associated pneumonia (VAP) and causative microorganisms according to different histologic and microbiological references. DESIGN: Immediate, multiple bilateral lung biopsy, postmortem study. SETTING: Respiratory intensive care unit of a 1,000-bed teaching hospital. PATIENTS: Twenty-five mechanically ventilated patients (>72 hrs) who died in our intensive care unit. MEASUREMENTS: Lung tissue histologic examination and quantitative cultures (16 specimens/patient). The following four references for the diagnostic techniques were used: histology of guided lung biopsy, histology of blind lung biopsy, combined guided and blind lung biopsy histology and microbiology of lung tissue, and microbiology of lung tissue. RESULTS: Sensitivities when histologic reference tests were used ranged from 16% to almost 40%, whereas specificity rates were always <80%. When we combined both lung histology of guided or blind specimens and microbiology of lung tissue, all diagnostic techniques achieved considerably higher but still limited diagnostic yields (sensitivity range 43% to 83%; specificity range 67% to 91%). Causative organisms were missed in a significant number of cases by all techniques (17% to 83%). CONCLUSIONS: The diagnostic performances of different diagnostic techniques strongly depend on the reference used. All techniques for detecting VAP are of limited value. Finding a balance between clinical judgment and microbiological results is crucial to appropriately manage patients with VAP.

Biopsy↗
PubMed2000

Anesthetic management of surgical neuroendoscopies: usefulness of monitoring the pressure inside the neuroendoscope.

Neuroendoscopic procedures are increasing in frequency in neurosurgical practice. We describe the anesthetic technique and the perioperative complications found in 100 neuroendoscopic interventions performed at our institution. Cranial tumor biopsy or retrieval (62%) and cisternostomy for hydrocephalus (33%) were the most frequent indications for neuroendoscopy. The mortality rate was low (1%). Intraoperative complications occurred in 36 patients, with arterial hypertension being the most frequent (53%). Postoperative complications occurred in 52 patients; anisocoria (31%) and delayed arousal (29%) were the most frequent. The pressure inside the endoscope was monitored intraoperatively in the last 47 patients. A saline-filled catheter from a pressure transducer connected to the neuroendoscopy system was used for pressure monitoring. We recorded the highest peak of pressure values measured during each procedure. Twenty-three patients (49%) had peak pressure values >30 mm Hg, 12 patients (25%) >50 mm Hg, and 3 patients >100 mm Hg. Only one patient had hemodynamic changes occurring simultaneously with the pressure changes. We found an association between pressure inside the endoscope >30 mm Hg and postoperative (P = .003) but not intraoperative complications. A relationship was found between surgical duration and postoperative complications (P = .002). Neither the pressure inside the endoscope or the intraoperative morbidity were related to surgical duration. We conclude that there may be a high rate of postoperative complications after neuroendoscopies, namely, new neurologic deficits. High pressure levels inside the endoscope during neuroendoscopic procedures can occur without hemodynamic warning signs. Pressure values >30 mm Hg are associated with postoperative morbidity, especially unexpected delayed recovery. Measuring the pressure inside the endoscope is technically easy and might be beneficial if performed in all neuroendoscopic procedures. Reducing the incidence of episodes of high peak pressure values might decrease the rate of postoperative complications.

Adult↗
PubMed1999

Clinical diagnosis of ventilator associated pneumonia revisited: comparative validation using immediate post-mortem lung biopsies.

BACKGROUND: A study was undertaken to assess the diagnostic value of different clinical criteria and the impact of microbiological testing on the accuracy of clinical diagnosis of suspected ventilator associated pneumonia (VAP). METHODS: Twenty five deceased mechanically ventilated patients were studied prospectively. Immediately after death, multiple bilateral lung biopsy specimens (16 specimens/patient) were obtained for histological examination and quantitative lung cultures. The presence of both histological pneumonia and positive lung cultures was used as a reference test. RESULTS: The presence of infiltrates on the chest radiograph and two of three clinical criteria (leucocytosis, purulent secretions, fever) had a sensitivity of 69% and a specificity of 75%; the corresponding numbers for the clinical pulmonary infection score (CPIS) were 77% and 42%. Non-invasive as well as invasive sampling techniques had comparable values. The combination of all techniques achieved a sensitivity of 85% and a specificity of 50%, and these values remained virtually unchanged despite the presence of previous treatment with antibiotics. When microbiological results were added to clinical criteria, adequate diagnoses originating from microbiological results which might have corrected false positive and false negative clinical judgements (n = 5) were countered by a similar proportion of inadequate diagnoses (n = 6). CONCLUSIONS: Clinical criteria had reasonable diagnostic values. CPIS was not superior to conventional clinical criteria. Non-invasive and invasive sampling techniques had diagnostic values comparable to clinical criteria. An algorithm guiding antibiotic treatment exclusively by microbiological results does not increase the overall diagnostic accuracy and carries the risk of undertreatment.

Anti-Bacterial Agents↗
PubMed1997

Significance of the isolation of Candida species from respiratory samples in critically ill, non-neutropenic patients. An immediate postmortem histologic study.

The diagnosis of pulmonary candidiasis is still controversial. We undertook a prospective study on 25 non-neutropenic, mechanically ventilated (> 72 h) patients who died in our ICU with the aim of assessing the incidence and significance of the isolation of Candida species from quantitative cultures of immediate postmortem lung biopsies and different respiratory sampling techniques. Immediate postmortem respiratory samples (endotracheal aspirate, protected specimen brush [PSB], bronchoalveolar lavage [BAL], blind biopsies [average 14/patient], and bilateral bronchoscopically guided biopsies [two per patient]) were taken from all patients. Lung tissue specimens were histologically examined. Respiratory samples were classified as having Candida or otherwise. Ten (40%) patients had at least one pulmonary biopsy yielding Candida spp. Among these 10 patients with Candida isolates, only two had definite pulmonary candidiasis. A total of 470 microorganisms were isolated from 280 of 375 (77%) lung biopsy samples in all 25 patients. Candida species represented 9% (n = 40) of the isolates, corresponding to 10 patients (40%). In the 10 patients in whom Candida species was isolated from pulmonary biopsies, this was always associated with the isolation of the same microorganism from one of the sampling methods. Quantitative cultures of Candida species from different sampling methods correlated well among each other but could not discriminate the presence from absence of Candida pneumonia. A logistic regression model adjusted for the presence of antibiotics, days of antibiotic treatment, mechanical ventilation period, age, ARDS, parenteral nutrition, and gender did not show any independent risk factor for developing positive pulmonary samples for Candida species. The incidence of Candida isolation from pulmonary biopsies in critically ill mechanically ventilated, non-neutropenic patients who die is high (40%). However, the incidence of definite Candida pneumonia was 8%. We also found that Candida colonization is uniform throughout the different lung regions, and that the presence of Candida in respiratory samples, independently of quantitative cultures, is not a good marker of Candida pneumonia in critically ill, non-neutropenic, non-AIDS patients.

Adult↗
PubMed1996

Histopathologic and microbiologic aspects of ventilator-associated pneumonia.

BACKGROUND: The relationship between microbiology and histology in patients with ventilator-associated pneumonia has been sparsely described. METHODS: Twenty-five patients who died in the intensive care unit after their lungs had been mechanically ventilated for 72 h were studied. Twenty of the 25 died with clinical suspicion of pulmonary infection. A total of 375 immediate postmortem pulmonary biopsies were obtained after death and processed for quantitative microbiology and histology. Four evolutionary stages of pneumonia were defined: early, intermediate, advanced, and resolution. RESULTS: At least one specimen with histologic evidence of pneumonia was found in all but two patients (92%). Histologic pneumonia was a widespread and frequent process (46%) of biopsies examined) involving predominantly the lower lobes (55% of all biopsies with pneumonia) and showing different histopathologic stages of progression coexisting in the same lung lobes. Lung cultures were frequently polymicrobial (149 of 375, 40% of the pulmonary biopsy cultures, and 20 of 25, 80% of the cases) and not always yielding the same pathogen (19 microorganisms) when comparing one lung to the other. Histopathology and microbiologic biopsy cultures showed a weak relationship (28% and 49% of species had counts > or = 10(3) cfu/g in samples without pneumonia from patients with and without prior antibiotic treatment, respectively). Histopathologic evolutionary stages were not associated with any differences in quantitative culture results of pulmonary biopsies, independently of prior administration of antibiotics. Higher bacterial concentrations of biopsy cultures were associated with the absence of prior antibiotic treatment. CONCLUSIONS: Ventilator-associated pneumonia is a frequent diffuse and polymicrobial process showing different coexisting degrees of evolution and involving preferentially the lower lobes. Microbiology and histology can be dissociated even in the absence of prior antibiotic treatment. Lung histology appears more reliable than bacteriology as a diagnostic reference test.

Adult↗
PubMed1996

Stomach as a source of colonization of the respiratory tract during mechanical ventilation: association with ventilator-associated pneumonia.

The aetiopathogenesis of ventilator-associated pneumonia (VAP) requires abnormal oropharyngeal and gastric colonization and the further aspiration of their contents to the lower airways. VAP develops easily if aspiration or inoculation of microorganisms occur in patients with artificial airways, in whom mechanical, cellular and/or humoral defences are altered. Well-known risk factors for gastric colonization include: alterations in gastric juice secretion; alkalinization of gastric contents; administration of enteral nutrition; and the presence of bilirubin. However, the role of the colonized gastric reservoir in the development of VAP remains debatable. Evidence in favour of the role of the stomach in the development of VAP comes mainly from randomized, controlled trials of selective gut decontamination and stress ulcer prophylaxis in the intensive care unit (ICU), in which reducing the bacterial burden of the stomach decreases the incidence of nosocomial respiratory infections. However, at least three studies of flora have found an absence of stomach origin of pneumonia occurring during mechanical ventilation. Prophylactic measures suggested to prevent VAP in relation to the gastric reservoir include: treatment for stress ulcers with sucralfate; prevention of duodenal reflux with metoclopramide; reduction of gastric burden and bacterial translocation by selective digestive decontamination; acidification of enteral feeding; and jejunal feeding. Gastro-oesophageal reflux can be prevented by using small bore nasogastric tubes and jejunal feeding. The aspiration of gastric contents can be reduced by positioning patients in a semirecumbent position, checking the patency of the tube cuff, and aspiration of subglottic secretions. The role of the stomach as a reservoir for microorganisms causing ventilator-associated pneumonia is still controversial but despite the debate, there is major evidence in the literature in favour of the gastric origin of part of these pulmonary infections.

Colony Count, Microbial↗
PubMedDate not supplied

[Use of the electroencephalographic spectral edge frequency 90 to monitor sedation of chronically ill patients].

INTRODUCTION: The depth of sedation required for patients in critical care units varies over time and should be subject to control. The clinical assessment scales used at present are inadequate, and several electroencephalographic variables have been investigated in recent years with the aim of quantifying depth of sedation. One such variable is the spectral edge frequency 90 (SEF90). OBJECTIVES: To establish the correlation between SEF90 and the Ramsay score as indicators of depth of sedation. To estimate the ability of SEF90 to predict sedation and a patient's hemodynamic response during aspiration of secretions through the orotracheal tube. PATIENTS AND METHODS: Patients in a surgical intensive care unit. The ability of SEF90 to predict a certain Ramsay score was assessed by logistic regression. We also calculated the predictive probability (Pk) of SEF90 for the appearance of hemodynamic change and of movement in the event of endotracheal aspiration. RESULTS: When SEF90 was < 16 Hz, the probability of a Ramsay score >= 4 was >= 90% (Pk = 0.91). Neither SEF90 nor the Ramsay score predicted hemodynamic response to orotracheal aspiration. CONCLUSIONS: SEF90 distinguishes superficial from deep sedation but does not differentiate further degrees of depth or the likelihood of hemodynamic instability or movement in response to aspiration.

Anesthesia↗
PubMedDate not supplied

[Complications during epilepsy surgery. Experience after 102 interventions between 1997 and 2001].

OBJECTIVES: To describe perioperative complications in different approaches to surgery for epilepsy. PATIENTS AND METHODS: All patients undergoing surgery related to epilepsy between January 1997 and December 2001 were studied. We gathered information on patient characteristics, diagnosis, anticonvulsant treatment, surgical procedure, type of anesthesia and perioperative complications. RESULTS: Ninety-eighty patients underwent 90 procedures under general anesthesia and 12 procedures with local anesthesia and sedation. Surgery was for anteromedial temporal resection in 74 patients, electrode implantation through the foramen ovale in 10 patients, extratemporal excisions in 7 patients, callosotomy in 3 patients, functional hemispherectomy in 3 patients, implantation of electrode grids in 2 patients, and craniotomy with an awake patient in 3 cases. Complications related to the surgical procedure were intraoperative bradycardia (5 cases), dural tension at the start of surgery (3), bleeding (2) and seizure (1). Complications related to anesthesia were bronchospasm (2 cases), histamine-releasing reaction upon administration of the muscle relaxant (1), and difficult intubation (1). During recovery we saw 1 case of postoperative aphasia, 1 of polyuria, 1 of pulmonary condensation, and 1 of factor VII deficit requiring plasma transfusion. CONCLUSIONS: The rate of perioperative complications in surgery for drug-resistant epilepsy is low, the most common complication being self-limiting bradycardia related to surgical maneuvers.

Adult↗