Cuidados intensivos orientados a la donación de órganos. Recomendaciones ONT-SEMICYUC / Intensive care to facilitate organ donation. ONT-SEMICYUC recommendations

Los cuidados intensivos orientados a la donación (CIOD) se definen como el inicio o la continuación de medidas de soporte vital, incluyendo la ventilación mecánica, en pacientes con lesión cerebral catastrófica y alta probabilidad de evolucionar a muerte encefálica, en los que se ha descartado cualquier tipo de tratamiento. Los CIOD incorporan la opción de la donación de órganos permitiendo un enfoque holístico en los cuidados al final de la vida coherente con los deseos y valores del paciente. Si el paciente no evoluciona a muerte encefálica, se deben retirar las medidas de soporte vital valorando la donación en asistolia controlada. Los CIOD respetan el marco ético y legal y contribuyen a aumentar las probabilidades de los pacientes de acceder a la terapia de trasplante, generando salud, incrementando la donación en un 24% con una media de 2,3 órganos trasplantados por donante y contribuyendo a la sostenibilidad del sistema sanitario. Estas recomendaciones ONT-SEMICYUC proporcionan una guía para facilitar una práctica armonizada de los CIOD en las UCI españolas. (AU)

Intensive care to facilitate organ donation (ICOD) is defined as the initiation or continuation of life-sustaining measures, such as mechanical ventilation, in patients with a devastating brain injury with high probability of evolving to brain death and in whom curative treatment has been completely dismissed and considered futile. ICOD incorporates the option to organ donation allowing a holistic approach to end-of-life care, consistent with the patients wills and values. Should the patient not evolve to brain death, life-supportive treatment must be withdrawal and controlled asystolia donation could be evaluated. ICOD is a legitimate practice, within the ethical and legal regulations that contributes increasing the accessibility of patients to transplantation, promoting health by increasing deceased donation by 24%, and with a mean of 2.3 organs transplanted per donor, and collaborating with the sustainability of health-care system. This ONT-SEMICYUC recommendations provide a guide to facilitate an ICOD harmonized practice in spanish ICUs. (AU)

[Intensive care to facilitate organ donation. ONT-SEMICYUC recommendations]. / Cuidados intensivos orientados a la donación de órganos. Recomendaciones ONT-SEMICYUC.

Intensive care to facilitate organ donation (ICOD) is defined as the initiation or continuation of life-sustaining measures, such as mechanical ventilation, in patients with a devastating brain injury with high probability of evolving to brain death and in whom curative treatment has been completely dismissed and considered futile. ICOD incorporates the option to organ donation allowing a holistic approach to end-of-life care, consistent with the patients wills and values. Should the patient not evolve to brain death, life-supportive treatment must be withdrawal and controlled asystolia donation could be evaluated. ICOD is a legitimate practice, within the ethical and legal regulations that contributes increasing the accessibility of patients to transplantation, promoting health by increasing deceased donation by 24%, and with a mean of 2.3 organs transplanted per donor, and collaborating with the sustainability of health-care system. This ONT-SEMICYUC recommendations provide a guide to facilitate an ICOD harmonized practice in spanish ICUs.

Intensive care practices in brain death diagnosis and organ donation.

We conducted a multicentre study of 1844 patients from 42 Spanish intensive care units, and analysed the clinical characteristics of brain death, the use of ancillary testing, and the clinical decisions taken after the diagnosis of brain death. The main cause of brain death was intracerebral haemorrhage (769/1844, 42%), followed by traumatic brain injury (343/1844, 19%) and subarachnoid haemorrhage (257/1844, 14%). The diagnosis of brain death was made rapidly (50% in the first 24 h). Of those patients who went on to die, the Glasgow Coma Scale on admission was ≤ 8/15 in 1146/1261 (91%) of patients with intracerebral haemorrhage, traumatic brain injury or anoxic encephalopathy; the Hunt and Hess Scale was 4-5 in 207/251 (83%) of patients following subarachnoid haemorrhage; and the National Institutes of Health Stroke Scale was ≥ 15 in 114/129 (89%) of patients with strokes. Brain death was diagnosed exclusively by clinical examination in 92/1844 (5%) of cases. Electroencephalography was the most frequently used ancillary test (1303/1752, 70.7%), followed by transcranial Doppler (652/1752, 37%). Organ donation took place in 70% of patients (1291/1844), with medical unsuitability (267/553, 48%) and family refusal (244/553, 13%) the main reasons for loss of potential donors. All life-sustaining measures were withdrawn in 413/553 of non-donors (75%).

Setting maximum limits for trace elements in baby food in European legislation: the outcome of International Measurement Evaluation Programme®-33.

The Institute for Reference Materials and Measurements (IRMM) of the Joint Research Centre (JRC), a Directorate-General of the European Commission, operates the International Measurement Evaluation Programme® (IMEP). It organises various types of inter-laboratory comparisons in support of European Union policies. This paper presents the results of a proficiency testing exercise (PT) focusing on the determination of total cadmium (Cd) and total lead (Pb) mass fractions in baby food in support to Commission Regulation (EC) 1881/2006 of 19 December 2006 setting maximum levels for certain contaminants in foodstuffs. The test material used in this exercise was soya-based baby food formula purchased in a local pharmacy and prepared by the Reference Materials Unit of the IRMM for this exercise. Sixty-six laboratories from 23 countries registered to the exercise and 61 of them reported results. Each participant received one bottle containing approximately 15 g of test material. Participants were asked to quantify the measurands in the powder and in the reconstituted formula. Reference values independent from the participants' results were established using isotope dilution inductively coupled plasma mass spectrometry. The total Cd mass fraction was determined by IRMM and LGC Ltd (UK), while the total Pb was determined by IRMM. The standard deviation for proficiency assessment σ^ was set at 22% of the assigned value for all measurands. Laboratories were rated with z- and ζ- (zeta) scores in accordance with ISO 13528. The outcome of this exercise is clearly influenced by the very low level of Cd and Pb content in the test material which triggered: a high number of 'less than' values; overestimated values especially for Pb very likely due to contamination; and a visible method influence in the case of Pb (methods based on atomic absorption were not sensitive enough to attain such low limits of detection). The results were also evaluated with regard to the reported limit of detection and some incoherencies were observed.

Screening test to detect meat adulteration through the determination of hemoglobin by cation exchange chromatography with diode array detection.

A simple sample preparation procedure, consisting of an extraction step with Milli-Q water as extraction solvent for hemoglobins from meat samples, followed by a filtration step with a cellulose acetate filter, is applied. After cation exchange chromatographic separation and diode array detection, different peak patterns for extracted hemoglobins of cow, lamb or pork meat are obtained. Other heme-group containing proteins like myoglobin or cytochrome C, which could be also detected with diode array detection at 416 nm, are chromatographically separated from the hemoglobins. By the use of these characteristic peak patterns, the species of the meat can be specified permitting the qualitative assessment of meat adulteration with the proposed screening method.

[Rombencephalitis due to Listeria monocytogenes. Probable usefulness of dexamethasone associated with antibiotic treatment]. / Rombencefalitis por Listeria monocytogenes. Probable utilidad de la dexametasona asociada al tratamiento antibiótico.

INTRODUCTION: Infection of the central nervous system by Listeria monocytogenes appears in most cases as acute meningitis which is indistinguishable from other types of acute meningitis. Rombencephalitis is a rare form of neurolisteriosis, localized to the brainstem. The initial non specific symptoms may make early diagnosis difficult. CASE REPORT: We describe the clinical case of a previously healthy woman who had L. monocytogenes infection localized to the brainstem. Her initial symptoms were fever and headache followed by signs of brainstem involvement, deterioration of consciousness and severe respiratory insufficiency which made mechanical ventilation necessary. Study of the cerebrospinal fluid showed lymphocytic pleocytosis, raised protein and normal glucose levels. L. monocytogenes was isolated on blood culture. Cranial computerized tomography was normal and magnetic resonance showed a right pontobulbar lesion. After receiving specific antibiotic treatment the infectious condition improved. However, the neurological symptoms started to improve when dexamethasone was added to the antibiotic treatment twelve days later. The patient was discharged from hospital with slight neurological sequelas. CONCLUSION: In a febrile patient with signs of brainstem involvement, neurolisteriosis should be suspected and ampicillin and gentamycin added to the treatment. The possibility of acute respiratory arrest occurring makes it necessary to monitor these patients closely. The association of dexamethasone to the antibiotic treatment may be useful in some cases of rombencephalitis due to L. monocytogenes.

Identification and quantification of major bovine milk proteins by liquid chromatography.

In the field of food quality, bovine milk products are of particular interest due to the social and economic importance of the dairy products market. However, the risk of fraudulent manipulation is high in this area, for instance, replacing milk powder by whey is very interesting from an economic point of view. Therefore, there is a need to have suitable analytical methods available for the determination of all milk components, which is currently not the case, especially for the main proteins. The detection of potential manipulations requires then a clear analytical characterisation of each type of bovine milk, what constitutes the goal of this work. The separation of the major milk proteinic components has been carried out by ion-pair reversed-phase HPLC with photodiode array detection, using a C4 column. The overall optimisation has been achieved using a statistical experimental design procedure. The identification of each protein was ascertained using retention times, peak area ratios and second derivative UV spectra. Quantification was based on calibration curves drawn using purified proteins. Major sources of uncertainty were identified and the full uncertainty budget was established. The procedure was initially developed using the skimmed milk powder certified reference material CRM 063R and then applied to various types of commercial milks as well as to raw milk. The method is able to separate and quantify the seven major proteins (K-casein, alphas2-casein, alphas1-casein, beta-casein, alpha-lactalbumin, beta-lactoglobulin B and beta-lactoglobulin A) in one run and also to provide precise determinations of the total protein concentration. These are important results towards the further development of a reference method for major proteins in milk. In addition, the use of a certified material reference is suggested in order to make comparisons of method performances possible.

[Acute eosinophilic pneumonia in a pregnant woman]. / Neumonía eosinófila aguda en gestante.

Acute eosinophilic pneumonia is a recently described pulmonary phenomenon involving rapidly progressing respiratory insufficiency. Although it can appear at any age, it has never been reported during pregnancy and its impact on gestation is therefore unknown. We describe the clinical signs and course of disease in this first report of acute eosinophilic pneumonia in a pregnant woman. We emphasize the diagnostic utility of bronchoalveolar lavage, the resolution of symptoms without corticoid treatment and, mainly, the absence of adverse repercussions of the disease on pregnancy.

Comparison of one versus two bronchodilators in ventilated COPD patients.

OBJECTIVE: To compare the bronchodilating effect of a single drug, ipratropium bromide (IBr), with that of its combination with fenoterol (IBr+F). DESIGN: The study was triple blind and randomized. SETTING: Medical-surgical intensive care unit. PATIENTS: 12 patients with acute exacerbation of chronic obstructive pulmonary disease (COPD) requiring mechanical ventilation for severe respiratory failure. INTERVENTIONS: Before administering each drug, peak airway pressure (Ppeak), end inspiratory pressure (Pei), resistive pressure (Pres), and auto positive--end expiratory pressure (auto-PEEP) were measured. Inspiratory system resistance (Rins) and dynamic respiratory system compliance (C) were calculated. Arterial pH and blood gas determinations were made. These measurements were repeated 60 min after administration of each therapeutic regimen. For ipratropium bromide alone the dose was 0.04 mg. When the combination of drugs was used, the doses were 0.04 mg for ipratropium bromide and 0.1 mg for fenoterol. MEASUREMENTS AND RESULTS: With the combination of both drugs, all the pressures in the airway, as well as the auto-PEEP and the Rins were significantly reduced (p < 0.05) with respect to baseline values. With ipratropium bromide alone, no significant changes were observed either in the pressures or in the inspiratory resistance. No significant changes were observed either in the pH or blood gases with any of the treatments. The combination of both drugs produced significantly reduction in Pei and auto-PEEP when compared with ipratropium bromide alone. CONCLUSIONS: The combination of both drugs is more effective than ipratropium bromide alone at the doses used in this study.

Pressure-controlled ventilation versus controlled mechanical ventilation with decelerating inspiratory flow.

OBJECTIVE: To ascertain whether pressure-controlled ventilation offers any advantage with respect to conventional controlled mechanical ventilation with decelerating flow. DESIGN: Prospective, comparative study. SETTING: Intensive care unit. PATIENTS: Eleven consecutive critically ill adult patients. MEASUREMENTS AND MAIN RESULTS: Study of respiratory mechanics and arterial blood gases after 30 mins of pressure-controlled ventilation. Repetition of the same measurements after 30 mins of controlled mechanical ventilation with decelerating flow waveform, with equal tidal volumes, using a commercially available mechanical ventilator. Student's t-test for paired comparisons. A lesser maximum inspiratory flow rate was required for pressure-controlled ventilation (55.7 +/- 16 L/sec) than for controlled mechanical ventilation (72 +/- 2 L/sec) (p < .001). Nevertheless, the peak pressures measured in the orotracheal tubes of the patients were higher in pressure-controlled ventilation (20.4 +/- 3.5 cm H2O) than in controlled mechanical ventilation (18.4 +/- 4.8 cm H2O) (p < .05). This model measured pressure in the inspiratory line, providing erroneous information regarding the behavior of pressures in the airway. The peak pressure measured by the ventilator was significantly higher in controlled mechanical ventilation than in pressure-controlled ventilation and was, in addition, reached at initiation of inspiration in ten of 11 patients with controlled mechanical ventilation, while peak pressure measured in the orotracheal tube was invariably reached at the end of the inspiration, both in pressure-controlled ventilation and controlled mechanical ventilation. The rest of the parameters analyzed, including end-inspiratory pressure, mean pressure, intrinsic positive end-expiratory pressure, and arterial blood gases, showed no differences. The difference between quasi-static compliances almost reached statistical significance (72 +/- 25.4 mL/cm H2O in pressure-controlled ventilation vs. 68.8 +/- 24.3 mL/cm H2O in controlled mechanical ventilation; p = .052). CONCLUSIONS: Our study failed to demonstrate any important difference between pressure-controlled ventilation and controlled mechanical ventilation with decelerating inspiratory flow waveform. The differences in the airway pressures detected by the ventilator are spurious and are due to the place (inspiratory line) where these pressures were measured. The difference between the peak pressure measured in the orotracheal tube has statistical, but not clinical, value and is lower in controlled mechanical ventilation. Based on the limited number of variables we studied and unless the tendency indicated in the quasi-static compliance is demonstrated in the future, we do not believe that pressure-controlled ventilation contributes any uniqueness to the theory or practice of mechanical ventilation.

Interaction between intrinsic positive end-expiratory pressure and externally applied positive end-expiratory pressure during controlled mechanical ventilation.

OBJECTIVE: To assess the interaction between intrinsic and externally applied positive end-expiratory pressure (intrinsic PEEP and administered PEEP) in mechanically ventilated patients. DESIGN: Prospective study. SETTING: Intensive care unit of a university hospital. PATIENTS: Twelve consecutive critically ill patients. INTERVENTIONS: Application of an external PEEP of the same value as the intrinsic PEEP. MEASUREMENTS AND MAIN RESULTS: We found that when the administered PEEP was increased from 0 to the baseline value of intrinsic PEEP, mean intrinsic PEEP decreased from 6.5 +/- 4.2 (SD) to 1.3 +/- 0.7 cm H2O (p = .001). The mean end-inspiratory pressure was increased from 20.3 +/- 4.6 to 23.1 +/- 6.1 cm H2O (p < .05). The difference between the modification of intrinsic PEEP and the change in the end-inspiratory pressure was not significantly > 0 cm H2O. Thus, the increase in end-inspiratory pressure may be directly attributable to the increase in total PEEP (administered PEEP plus intrinsic PEEP). None of the other measurements of pulmonary mechanics changed (peak pressure, inspiratory resistance, compliance, and trapped-gas volume). CONCLUSIONS: The administration of positive end-expiratory pressure equal to the intrinsic positive end-expiratory pressure causes the almost total disappearance of the intrinsic positive end-expiratory pressure. When the administered positive end-expiratory pressure does not exceed the intrinsic positive end-expiratory pressure, the former is applied almost in its entirety to the patient's external circuit. The administration of positive end-expiratory pressure without prior quantification of the intrinsic positive end-expiratory pressure results in an overestimation of the beneficial effects of the administered positive end-expiratory pressure on the quasi-static compliance.

Right ventricular systolic time intervals determined by means of a pulmonary artery catheter.

OBJECTIVES: To evaluate the right ventricular systolic time interval as an index of right ventricular function and also to ascertain whether the right ventricular ejection fraction may be determined by means of a conventional pulmonary artery catheter. DESIGN: Prospective study. SETTING: Intensive care unit. PATIENTS: Eight, consecutive critically ill adult patients. METHODS: Simultaneous blind measurements, performed by two investigators, of the right ventricular systolic time interval and right ventricular ejection fraction, determined by means of a pulmonary artery catheter. Two studies, separated by an interval of 24 hrs, per patient. Linear regression analysis. Multiple regression test. RESULTS: Of the 16 studies performed, two determinations of right ventricular systolic time intervals were technically inadequate. In the remaining 14 valid studies, we found one close linear correlation between the right ventricular ejection fraction and the preejection period/ejection time quotient measured using the simultaneous display of the electrocardiogram (EKG) and pulmonary arterial pressure curve (r2 = .90, p < .001, right ventricular ejection fraction = 68.96-60.59 x [right ventricular preejection period/right ventricular ejection time]). The method proved to be simple, very accurate, with little interobserver variation (8.09 +/- 10.6% interobserver variation for right ventricular preejection period/right ventricular ejection time) and provided adequate information regarding situations in which the performance of the right ventricle is modified in a given patient. The right ventricular preejection period/right ventricular ejection time quotient was the only variable that displayed a significant relationship with the right ventricular ejection fraction in the multivariate analysis (p < .001). CONCLUSIONS: Right ventricular systolic time intervals, measured using the simultaneous display of the pulmonary artery catheter curve and EKG, provide adequate information regarding right ventricle performance in critically ill patients. The close linear correlation between the right ventricular preejection period/right ventricular ejection time quotient and the right ventricular ejection fraction enables the investigator to estimate, with a high degree of accuracy, the right ventricular ejection fraction and the values derived from the preload of the right ventricle, without the need for a modified pulmonary artery catheter.

Population pharmacokinetic study of gentamicin and a Bayesian approach in patients with renal impairment.

A population pharmacokinetic study was conducted on a total of 70 patients receiving gentamicin therapy. The patients included those with normal renal function and those with varying degrees of renal impairment. The parameters studied were the apparent volume of distribution and the plasma clearance of gentamicin. The interindividual variability and the residual variability of those parameters in the different subpopulations were studied according to a statistical model that assumed log normal distribution. Use of the one-way ANOVA test revealed statistically significant differences (P = 0.004) in the population plasma clearance of gentamicin in patients below and above 50 years of age. A linear relationship was established between the plasma clearance of gentamicin and the creatinine clearance in those patients. At the same time, the coefficient of variation of the Clp increased progressively in patients with renal impairment, varying between 28.98% in patients with a ClCR greater than 100 ml/min and 76.53% in patients with a ClCR between 20 and 60 ml/min. The results obtained in the population study were later applied to drug monitoring in 23 patients with varying degrees of renal function and who received gentamicin therapy with different doses. The residual variability of the population allowed us to calculate a weighting factor (FF) between the experimental and the population data using Bayesian fitting. The weighting factor was 0.89 in patients with normal renal function and 0.80 in patients with renal impairment. Statistical comparison of the pharmacokinetic parameters obtained from the populational data, non-linear regression and the Bayesian method using revealed differences in the values for the apparent volume of distribution obtained with the two methods.(ABSTRACT TRUNCATED AT 250 WORDS)