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P Nadal

Publications and source records attributed to P Nadal.

At least 19 recordsLinked to original sources
PubMed2006

Single cell variability of L. monocytogenes grown on liver pâté and cooked ham at 7 degrees C: comparing challenge test data to predictive simulations.

AIMS: The variability in growth between individual Listeria monocytogenes cells was investigated on liver pâté and cooked ham. These results were compared to Monte Carlo simulations based on data collected previously in broths (Francois et al., submitted for publication). METHODS AND RESULTS: Single cells were isolated by a dilution protocol and inoculated on 15 g samples of liver pâté and cooked ham, pasteurized in the packaging. Of each product, 250 samples were inoculated, of which 50 samples were analysed for L. monocytogenes on each analysis day. Results were compared to simulations, based on distributions that describe the variability of the individual cell lag phases and generation times of L. monocytogenes cultivated in broths. Based on the same simulation techniques, the variability effect was investigated for different inoculum levels (10, 100, 10,00 and 10,000 cells). It was demonstrated that the expected variability of the outgrowth of L. monocytogenes in a challenge test is very high for low inoculum levels. CONCLUSIONS: The variability in growth characteristics observed between different single L. monocytogenes cells on foods is very large. The simulations based on the previously collected optical density data in broths, could be confirmed by foods inoculated with single L. monocytogenes cells. SIGNIFICANCE AND IMPACT OF THE STUDY: The large variability between different individual L. monocytogenes cells has serious consequences for the experimental design of a challenge test. One thousand cells per portion are necessary in order to reduce the variability to acceptable levels and quantify the behaviour of the pathogen consistently with a reasonable number of challenge tests.

Animals↗
PubMed2000

Treatment of severe nosocomial pneumonia: a prospective randomised comparison of intravenous ciprofloxacin with imipenem/cilastatin.

BACKGROUND: A prospective multicentre study was undertaken to compare the efficacy of intravenous ciprofloxacin or imipenem in the treatment of severe nosocomial pneumonia requiring mechanical ventilation. METHODS: Patients with a clinical suspicion of pneumonia were randomised to receive either ciprofloxacin (800-1200 mg/day) or imipenem (2-4 g/day) in doses adjusted for renal function and specimens of the lower respiratory tract were taken. Patients were included in the study when specimens showed significant growth for potentially pathogenic microorganisms in quantitative bacterial cultures (n = 75, ciprofloxacin 41/75 (55%); imipenem 34/75 (45%)). The clinical and bacteriological success rates were the primary and secondary efficacy variables. An intent-to-treat analysis was performed for all randomised patients who received at least one dose of the study medication (n = 149, ciprofloxacin 72/149 (48%), imipenem 77/149 (52%)). RESULTS: The success rates were generally good, but neither the clinical success rates (ciprofloxacin, 29/41 (71%), imipenem, 27/34 (79%); 95% CI -10.8 to 28.1; p = 0.435) nor the bacteriological response rate (ciprofloxacin, 20/41 (49%), imipenem, 17/34 (50%); 95% CI -21.5 to 23.9; p = 1.0) were significantly different between the study arms. Pseudomonas aeruginosa was recovered in 26/75 patients (35%) and clinical (ciprofloxacin, 10/14 (71%), imipenem, 8/12 (67%); 95% CI -40.4 to 30.9; p = 1.0) and bacteriological response rates (ciprofloxacin, 7/14 (50%), imipenem, 3/12 (25%), 95% CI -60.9 to 10.9, p = 0.247) were not significantly different in this subgroup of patients. Resistance of Pseudomonas aeruginosa developed in 5/26 cases (19%), 1/14 (7%) to ciprofloxacin and 4/12 (33%) to imipenem (p = 0.147), and the mortality was 12/75 (16%) with no difference between treatment groups (ciprofloxacin, 8/41(24%), imipenem 4/34 (17%); p = 0.362). The clinical response was evaluable in 109/149 patients (73%) in the intent-to-treat analysis and was successful in 74/109 patients (68%). The clinical response rates were also not significantly different in the intent-to-treat analysis (ciprofloxacin, 34/52 (65%), imipenem, 40/57 (70%); 95% CI -12.8 to 22.3; p = 0.746). CONCLUSIONS: Treatment with either ciprofloxacin or imipenem was effective in a selected group of patients with microbiologically confirmed, severe nosocomial pneumonia requiring mechanical ventilation. Although no differences between the study medication could be documented in this trial, smaller differences between treatment arms may have been missed because of sample size limitations.

Adult↗
PubMed1997

[Severe Plasmodium falciparum malaria. Description of 5 cases].

In the last few years a considerable number of imported malaria has been reported in Spain, probably due the increased tourism to areas with endemic malaria, particularly with P. falciparum. This is the species more frequently associated with severe complications and the only one capable of causing cerebral malaria. In this report we review five cases of malaria which required intensive care because of their severity. None of the patients had received chemoprophylaxis. In all cases the admission criterion to the intensive care unit was the organic failure of one or more systems (renal failure and disseminated intravascular coagulation [DIC] mainly) or the presence of changes in the central nervous system. Parasitemia at admission was higher than 5% in all patients. One patient died on account of cerebral malaria. Only one patient had severe complications not directly associated with malaria. In patients who already have severity criteria, a negative parasitemia test during the clinical course does not necessarily implies a clinical improvement nor does it exclude the emergence of complications. On the other hand, a low parasitemic degree is never a contraindication for admission to the intensive care unit when severity criteria are present.

Adult↗
PubMed1995

Pneumonia in ventilated head trauma patients: the role of thiopental therapy.

The role of barbiturate therapy in the development of pneumonia in head trauma patients in the intensive care unit of a university hospital was studied retrospectively. A total of 151 ventilated head trauma patients were included in the study. Intravenous thiopentone was administered to 75 patients (Group A), and 76 patients were managed without thiopentone therapy (Group B). Pneumonia was diagnosed when a new persistent pulmonary infiltrate appeared, with at least two of the following: (a) fever greater than 38 degrees C, (b) a white blood cell count greater than 15,000/mm3, or (c) the presence of purulent bronchial secretions. On admission, there were no differences in the acute physiology and chronic health evaluation 2 revision (APACHE II) and Glasgow Coma Score between Groups A and B. Fifty-three per cent of the patients treated with thiopentone (Group A) developed pneumonia compared with 35% in Group B (odds ratio 1.85, 95% confidence interval 0.97-3.51). Gram-negative and Staphylococcus aureus organisms were the most frequently isolated in all cases. No differences in age, sex, APACHE II, Glasgow Coma Score, nutritional status or dexamethasone treatment were observed between the groups with and without pulmonary infection. In the multivariate analysis, prolonged mechanical ventilation before pneumonia and thiopentone treatment remained as the only independent risk factors for the appearance of pneumonia in head trauma patients (p = 0.001 for both). Nevertheless, thiopentone did not increase the rate of mortality in patients with pneumonia. In conclusion, head trauma victims treated with thiopentone have a greater risk for the development of nosocomial pneumonia independent of mechanical ventilation.

Adolescent↗
PubMed1994

[Acute myopathy related to the administration of glucocorticoids and neuromuscular blockers].

Two cases of acute myopathy following the administration of high doses of glucocorticoids in patients requiring mechanical ventilation and who were also administered neuromuscular blockers are presented. The patients were two women of 57 and 73 years of age. The doses of methylprednisolone administered were of 810 and 1,180 mg during the first 7 and 17 days, respectively. With regard to the total doses of neuromuscular blockers the first patient received 76 mg of pancuronium over 4 days while the second received 1,180 mg of atracurium over 17 days. This myopathy is characterized by a clinical and histological picture which differs from that associated to the chronic use of glucocorticoids being attributed to a toxic action of these drugs somewhat favored by immobilization due to the use of neuromuscular blockers. Given the lack of references in the literature on this entity in Spain a review was undertaken with the need for correct early diagnosis allowing differentiation from other causes of weakness such as ischemia of the cerebral trunk, polyradiculoneuritis and polyneuritis of critical patients being of note. Muscular biopsy is therefore very useful since very suggestive signs of this myopathy may be found. The disease is reversible with no effective treatment. An early rehabilitation program is the only method of shortening the convalescence period.

Acute Disease↗
PubMed1994

Posthypoxic myoclonus in intensive care.

Posthypoxic myoclonus (Lance-Adams' syndrome) is a rare complication of cardiorespiratory arrest. It has a better prognosis than other movement disorders secondary to brain ischaemia. We report a case of posthypoxic myoclonus in a 66-year-old woman after acute myocardial infarction and cardiopulmonary arrest. She had action and intention myoclonus, and these movements were also initiated by acoustic and pain stimuli. The origin of the myoclonus was probably subcortical, and it improved with clonazepam 2 mg t.i.d. We emphasize that early diagnosis is necessary in intensive care units in order to avoid misinterpretation of this syndrome and to start appropriate treatment.

Aged↗
PubMed1991

Statistical modeling of prognostic indices for evaluation of critically ill patients.

OBJECTIVE: To identify the most predictive association of variables from the usual indices of severity of illness by statistical objective analysis. DESIGN: Logistic regression analysis of the different variables of the most important indices. SETTING: A general critical care medicine group practice in a university hospital. PATIENTS: A total of 630 critical care patients age 12 to 87 yrs were evaluated. The most important indices of severity of illness and the corresponding variables were recorded and the patient's course was followed for 3 months after ICU admission. MEASUREMENTS AND MAIN RESULTS: One of our hypotheses was that the inclusion of an excessive number of variables to obtain the most common prognostic indices of mortality in critical care patients results in an underestimation of mortality and a redundancy of prognostic information. We performed a logistic regression analysis using the variables of the currently used indices of critical care prognosis: Acute Physiology Score, Simplified Acute Physiology Score, Acute Physiology Score-II, and Mortality Prediction Model. This mathematical approach resulted in a model of five variables: organ system failure, blood glucose, serum calcium, serum prothrombin activity, and serum osmolality. The score obtained from this model gave accurate prognostic criteria:sensitivity 91.2% and specificity 90%, using a cutoff point of 0.7; sensitivity 86% and, specificity 94%, using a cutoff point of 0.5. CONCLUSIONS: Our results show that suitable statistical management of the discriminant prognostic variables allows reduction of the number of variables of the severity indices currently used, obtaining five more predictive variables.

Adolescent↗
PubMed1990

[Predictive factors of mortality in a series of 61 patients with severe acute pancreatitis].

The predictive value of eight clinical variables and 20 analytical variables on mortality was retrospectively analyzed in 61 patients with severe acute pancreatitis, fulfilling at least three Ranson criteria, admitted to the ICU between 1977 and 1987. The mean age of the series was 57 +/- 16.6 years. Twenty seven were males and 34 females. The mortality rate was 60%. Univariate analysis demonstrated that the variables with greater predictive value of mortality were: age, days of hospitalization, presence of associated diseases, plasma lactodehydrogenase, more than 10% hematocrit decrease during the first 48 hours, plasma ureic nitrogen on admission and a value greater than 1.8 mmol/l during the first 48 hours, calcemia, arterial oxygen pressure, plasma albumin, and prothrombin time. A logistic regression multivariate analysis disclosed that the variables with independent predictive value of mortality were: age, serum ureic nitrogen, calcemia, arterial oxygen pressure, plasma albumin, and hematocrit decrease after 48 hours. When the patients were grouped according to the presence of less than three, three, four or more than four of these risk factors (being, the average the cutting point) we obtained a good prognostic discriminative power since the mortality in those groups was 0, 30%, 60%, and 100%, respectively.

Acute Disease↗