Aviation medicine: challenges for telemedicine.

The number and seriousness of medical problems on passenger-carrying aircraft in flight are increasing. Medical incidents occur at a rate of approximately 10-50 per million passengers carried. Medical equipment carried on commercial aircraft is limited to three items: a first-aid kit, an emergency medical kit and sometimes an automatic external defibrillator. Telephone medicine, a lower level of telemedicine support, is well established for commercial air operations. The availability of satellite telecommunications on passenger-carrying aircraft permits more sophisticated forms of telemedicine. Recent telemedicine experiments have involved the transmission of three-lead electrocardiograms (ECGs), heart rate, blood pressure, arterial oxygen saturation, end-tidal CO2, respiratory rate, body temperature and realtime video. The challenge is to demonstrate that such techniques are practicable, improve patient outcomes and are cost-effective.

[Reimplantation lesion in the postoperative period of lung transplantation. Incidence, predictive factors, prognosis and outcome. The Lung Transplantation Group of Vall d'Hebron University General Hospital]. / Lesión de reimplantación en el postoperatorio del trasplante pulmonar. Incidencia, factores predictivos, pronósticos y evolución. Grupo de Trasplante Pulmonar del Hospital General Universitari Vall d'Hebron.

BACKGROUND: Reimplantation disease (RD) is a postoperative complication in lung transplantation. It is defined as hypoxemia (PaO2/FiO2 ratio < 150 mmHg), radiologic infiltrates and decrease of lung compliance. The aim of the study was to analyze the incidence, predictive factors, prognosis and outcome of the patients with RD. PATIENTS AND METHOD: 49 patients submitted to lung transplantation (June 1991-December 1996) were admitted in our intensive care unit (ICU). Donor and recipient conditions, surgical parameters and outcome in ICU were analyzed. Mann-Whitney, Kruskall-Wallis, Fisher, Pearson and ANOVA-Friedman tests were used for statistical analysis according to the different variables. RESULTS: 49% of the patients (29/49) developed RD, which was influenced neither by lung disease, nor by the kind of transplantation or by ischemia time. All patients with a long surgical time developed RD, versus only 41% in those where surgery was undertaken in a shorter period of time, OR: 2.8 (1.5-5.7; p = 0.0016). The patients with RD improved showing a PaO2/FiO2 ratio of 176 and 235 mmHg at 24 and 48 h respectively (ANOVA, p < 0.00001). The patients with RD needed 14 days of mechanical ventilation versus 7 days in those without RD (p = 0.013). There were no statistically significant differences in stay and mortality in ICU. CONCLUSIONS: RD is a common complication in the postoperative phase of lung transplantation. It is present in almost all the patients with long surgical time. Almost all of them improve, with the same survival but a longer period of mechanical ventilation.

[Potential impact of measures to minimize drug costs in Aragon's primary care system]. / Impacto potencial de medidas de minimización de costes en la prestación farmacéutica en atención primaria de Aragón.

OBJECTIVE: To analyse the potential saving in pharmaceutical expenditure which the use of drug products of the same composition and lower price would suppose, by three high-consumption therapeutic sub-groups. DESIGN: Retrospective observation study. SETTING: Primary care. PARTICIPANTS: All the medical prescriptions of the doctors in the 121 primary care health districts in the three provinces of the Autonomous Community of Aragon during 1997, divided into the sub-groups: peptic ulcer (AO2B), lipid-lowering (B04A) and hypotensor drugs (C02). MEASUREMENTS AND MAIN RESULTS: Consumption, cost of treatment per day and potential saving of eight active principles belonging to these 3 sub-groups were calculated. Potential overall saving reached the figure of 972 million pesetas in Aragon in 1997. CONCLUSIONS: The alternative of prescribing drugs with an identical composition and lower price offers great potential savings in pharmaceutical expenditure, and may be a useful measure to improve the efficiency of health resources, and in particular those devoted to drug prescription.

[The prognostic value of eicosanoids in the acute respiratory distress syndrome]. / Valor pronóstico de los eicosanoides en el síndrome de distrés respiratorio agudo.

BACKGROUND: There is a great number of agents involved in the acute respiratory distress syndrome (ARDS) physiopathology, and some of them may have a prognostic value. The objective of the present study has been to analyse the prognostic value of eicosanoids in this syndrome. MATERIAL AND METHOD: A prospective study with 21 consecutive ARDS patients admitted to the intensive care unit of a therapy hospital in Barcelona, Spain, was carried out. In the first 48 h of the ARDS diagnosis, at baseline, the plasma levels, (in peripheral arterial and pulmonary arterial samples) of thromboxane B2 (TXB2), prostaglandin F1-alpha) (PGF1-alpha) and leukotriene B4 (LTB4) were analysed by RIA. Simultaneously we measured different pulmonary and systemic hemodynamical variables, as well as the pulmonary gas exchange data. We also studied the venous levels of the same eicosanoids in 17 healthy adults, used as reference. RESULTS: Plasma levels of eicosanoids in the ARDS patients were higher than reference subjects (p < 0.05). No differences were observed between systemic arterial and pulmonary arterial values. From all the eicosanoids, only LTB4, (in both systemic arterial and pulmonary blood), was correlated with LIS (r = 0.49, p < 0.05; and r = 0.45, p < 0.05, respectively). Patients who did not survive presented a lower systemic-pulmonary arterial gradient of eicosanoids levels than survivors (-1.27 vs -0.10 ng/ml; p < 0.01). CONCLUSIONS: In our ARDS patients only LTB4 plasma levels correlated with the severity of respiratory failure. Patients who did not survive presented a lower LTB4 gradient than survivors.

Anticoagulative effect of nitric oxide inhalation in ARDS.

Some studies have suggested that nitric oxide (NO) may cause platelet dysfunction. We present an ARDS patient who need this treatment, with a transient alteration of platelet function and a significant prolongation of bleeding time.

[Minimizing the costs of prescription of anti-infective drugs in two areas of primary health care]. / Un estudio de minimización de costes en la prescripción de antiinfecciosos en dos areas de atención primaria.

BACKGROUND: Pharmaceutical costs are the main cost item in basic health care. The need to contain health care expenditure has led to the search for alternatives in this area, one of which would be to foster a prescription policy which uses the cheapest presentation for each active principle. The aim of this study was to evaluate the amount which would be saved by prescribing the cheapest alternative from a selection of anti-infective drugs. METHODS: Pharmacy prescriptions in two different health areas were analyzed using the database on turnover of pharmaceutical products for 1995. Single principle drugs with anti-infective action were selected, and for each active principle and presentation the most economic alternative was sought using the records provided by the Ministry of Health and a cost minimisation analysis was undertaken. The cost of applying this prescription policy was not considered. RESULTS: Total pharmaceutical expenditure in the areas was pesetas 8.547 bn in 1995. Expenditure on selected anti-infective drugs was pesetas 522 million (6.1% of the total). The overall saving estimated was 7.63% (pesetas 39,901,778). This saving was centred on the following subgroups: penicillins, quinolones, cephalosporins and macrolides. Of potential savings identified, 75% would be achieved by prescribing the cheaper alternative of 2 active principles: amoxacillin and cyprofloxacine. CONCLUSIONS: The study shows the possibility of containing expenditure in our area and offers a basis for action in this direction. It would be advisable to increase information and training for prescribers and dispensers in order to stimulate the use of the most economical alternative of each medicament prescribed, especially in cases in which there are significant margins to be saved.

[Are the indicators used to measure efficiency in primary care adequate?]. / Son adecuados los indicadores que se utilizan en atención primaria para medir la eficiencia?

OBJECTIVE: Getting to know the opinion of area managers and Primary Health Care Facilities coordinators about the indicators used to measure the PHC output. DESIGN: Questionnaire via mail. Descriptive statistics. SETTING: Areas 2-5, and 3, Zaragoza, Spain. PATIENTS: Managing teams of these three areas and Primary Health Care facilities coordinators. MEASUREMENTS AND MAIN RESULTS: The questionnaire was sent to 57 Primary Health Care Facilities coordinators and 16 area managers which was answered 53% of them. In the range from 1 to 10 the so-called product achieved in the evaluation the highest marks have been: the Services offered by the PHCF (7.8), Coverage (7.8), Achievement of the Minimal Technical Rules (7.76) and Patient Satisfaction (7.51). The indicator that obtained the highest level of agreement was also the product achieved in the evaluation of the Services offered by PHCF. CONCLUSIONS: According to these results indicators normally used, related with number of visits are questioned by the professionals. Synthetic indexes recently introduced obtained better values.

Neurological disturbances and hyperdynamic shock in a patient with esophagocoloplasty.

A 39-year-old man, with no history of alcohol intake, who had had an esophago-ileo-colo-gastroplasty with ileotransversostomy, developed diplopia, seizures, metabolic acidosis, and cardiac failure and finally refractory hyperdynamic shock. He died 20 h after admission to our intensive care unit from cardiocirculatory collapse. Postmortem results revealed low erythrocyte transketolase activity, which was increased by 22% by in vitro addition of thiamine diphosphate (TDP effect). Cerebral pathology showed the alterations of Wernicke's encephalopathy. We discuss the possible mechanisms of fatal cardiovascular collapse and the unusual presentation of a case without a history of alcoholic intake or clinical malnutrition.

Prospective, randomised, multicentre study of meropenem versus imipenem/cilastatin as empiric monotherapy in severe nosocomial infections.

The clinical and bacteriological efficacy and the tolerability of meropenem versus imipenem/cilastatin (both 1 g t.i.d.) in severe nosocomial infections were compared in a multicentre, randomised, nonblinded study. A total of 151 patients were recruited; 133 (66 meropenem, 67 imipenem/cilastatin) were clinically evaluable and 84 (42 meropenem, 42 imipenem/cilastatin) bacteriologically evaluable. Most clinically evaluable patients (90%) were in intensive care units, required mechanical ventilation (72%), and had received previous antibiotic therapy (62%). The mean (+/- SD) APACHE II score was 15.2 (+/- 6.6) in the meropenem group and 17.8 (+/- 6.8) in the imipenem/cilastatin group. The primary infections were nosocomial lower respiratory tract infections (56% of patients), intra-abdominal infections (15%), septicaemia (21%), skin/skin structure infections (5%), and complicated urinary tract infections (3%); 35% of the patients had two or more infections. There was no significant difference between the meropenem and imipenem/cilastatin groups in the rates of satisfactory clinical (weighted percentage 87% vs. 74%) or bacteriological (weighted percentage 79% vs. 71%) response. There was a slightly higher rate of clinical success with meropenem against primary or secondary lower respiratory tract infection (89% vs. 76%). Drug-related adverse events occurred in 17% and 15% of meropenem and imipenem/cilastatin patients, respectively. Meropenem (1 g t.i.d.) was as efficacious as the same dose of imipenem/cilastatin in this setting, and both drugs were well tolerated.

Comparative study of propofol versus midazolam in the sedation of critically ill patients: results of a prospective, randomized, multicenter trial.

OBJECTIVES: To compare the effectiveness, characteristics, duration of action, hemodynamic and biochemical effects, and side effects of propofol and midazolam used for continuous intravenous sedation of ventilated critically ill patients. DESIGN: Multicenter, prospective, randomized, nonblinded study. SETTING: Nine Spanish general intensive care units (ICUs). PATIENTS: Ninety-eight patients admitted to the ICU who were mechanically ventilated and required sedation for a minimum of 48 hrs. INTERVENTIONS: Propofol or midazolam was used for induction and maintenance of continuous intravenous sedation for a maximum of 5 days. The effectiveness of those two regimens was assessed according to their effects on ventilatory management and the presence of agitation. MEASUREMENTS AND MAIN RESULTS: In 93% of the patients studied, there was a medical cause necessitating mechanical ventilation. The mean (+/-SD) duration of sedation was 81 +/- 25 hrs and 88 +/- 27 hrs for the propofol and midazolam groups, respectively. The induction dose was 2.24 +/- 0.43 mg/kg over 318 +/- 363 secs for propofol, and 0.22 +/-0.07 mg/kg over 33 +/-29 secs for midazolam. The maintenance dose was 2.8 +/-1.1 mg/kg/hr for propofol and 0.14 +/- 0.10 mg/kg/hr for midazolam. There was no difference regarding the opiate and muscle relaxant requirements between the two groups. Sedation with propofol was more effective in achieving patient-ventilator synchrony than that with midazolam after the first hour of treatment (p < .01). Patients sedated with propofol awoke more rapidly and with less variability that those patients sedated with midazolam (23 +/- 16 mins vs. 137 +/- 185 mins, respectively, p < .05), particularly in those patients requiring deep sedation (27 +/- 16 mins vs. 237 +/- 222 mins, respectively, p < .01). No hemodynamic or biochemical changes were detected in any of the treatment groups. During induction, five patients in the propofol group and two patients in the midazolam group had hypotension. CONCLUSIONS: In this population of critically ill patients, propofol is an effective and safe alternative for sedation, with some advantages, such as short duration of action and high effectiveness over the conventional regimen with benzodiazepines and opiates.

[Evaluation of the efficiency of primary care centers. Application of data analysis]. / Evaluación de la eficiencia en centros de atención primaria. Una aplicación del análisis envolvente de datos.

BACKGROUND: One of the major difficulties in evaluating the efficiency of Primary Medical Centres is that of integrating quantitative and qualitative data. METHODS: This study applies the Involved Data Analysis (DEA) for the purpose of evaluating the efficiency of Primary Medial Centres located in the Province of Zaragoza (Spain). DEA is a lineal programming technique that provides information on the relative efficiency of each unit, as compared to all other units. Output such as doctors and nursing services as well as variables relating to the quality of service, and input (personnel and pharmaceutical expenses) referring to 1994, were obtained from Area Management. RESULTS: Without taking qualitative variables into account, only 13 Primary Medical Centres reached maximum efficiency level 1. with a range of 0.53 to 1. Taking quality variables into account, 24 units reached optimum efficiency, with a range of 0.61 to 1. CONCLUSIONS: DEA is a useful tool for both qualitative and quantitative overall evaluation of input and output and identifies units that are inefficient as compared to others. Despite the difficulties involved, the method appears to be beneficial for management as a complementary aid to currently used techniques.

Pattern of tracheal colonization during mechanical ventilation.

The relationship between gastric (GC) and tracheal (TC) colonization and the development of ventilator-associated pneumonia (VAP) remains controversial. TC, GC, and pharyngeal (PC) colonization were studied serially in 80 patients with mechanical ventilation (MV) to ascertain the routes and onset of TC. Simultaneous sample from pharynx, stomach, and trachea were obtained throughout the MV period. Quantitative cultures were performed. Seventy-two patients (90%) had TC at some time during MV. Only 19 patients presented TC after PC or GC by the same microorganisms. Indigenous gram-negative and gram-positive microorganisms colonized mainly the trachea from the start of or during MV without previous PC or GC (p < 0.05). Pseudomonas were the microorganisms causing TC principally during MV without previous PC or GC (p < 0.005). Enterobacteria produced TC without a preferential route. Of the 12 patients who developed VAP, the microorganisms responsible had already colonized the trachea in 10 patients. Only 10 of the 21 microorganisms isolated in VAP had previously colonized the pharynx or stomach. In summary, although some microorganisms have preferential routes for producing TC, the microorganisms isolated frequently change during MV. TC precedes VAP in most patients, but only a minority develop a VAP; therefore, together with TC other factors must be involved in VAP development.

[Economic-health care indicators in 2 health areas: the cost of the "consultation product" of primary health teams]. / Indicadores económico-asistenciales en dos áreas sanitarias: el coste del "producto consulta" en equipos de atención primaria.

OBJECTIVE: To describe the main economic-healthcare indicators of Aragon Areas 2 and 5 in 1992. To quantify in economic terms the value of the medical and nursing consultations carried out by Primary Care teams. DESIGN: Cost-analysis type study (total costs). The criteria for attributing indirect costs were established by consensus. The data correspond to 1992 (real spending by each centre). The cost of the consultations was calculated in function of the overall activity undertaken and in line with the type of consultation. SETTING: Areas 2 and 5, Aragon. Calculation of the cost per consultation only for Primary Care teams (PCT). RESULTS: Spending per inhabitant and per year, both overall and broken down into care and pharmacy costs was 20,140 for PCT's (8,805 pesetas + 11,355 pes) and 23,153 pes for the traditional model (7,677 + 15,476 pes). Costs per consultation were: 1,031 pes for General Medicine plus 2,537 on Pharmacy; 1,765 pes for Paediatrics plus 716 on Pharmacy; 972 on nursing. Costs per consultation were also offered in function of the duration of each type of consultation and the health-care delivered. CONCLUSIONS: Overall, PCT's generated less expense per each insured person than the traditionally-based Consulting rooms. This situation is mainly due to Pharmacy costs, where the difference is over 4,000 pesetas. The evaluation of service costs in function of attendance supposes that, between two teams of equal composition and the same volume of spending, the more efficient will be that which produces the greater amount of services.

[Energy requirement in patients after liver transplantation]. / Requerimiento energético en pacientes postransplante hepático.

We have made a study of the energy requirements of liver transplant patients in the immediate post-operative phase, by comparing different methods. A study of energy use was made with indirect Calorimetry (IC), of calculation of Resting Energy Expenditure (REE) according to Fick's formula modified by Liggett, and of the calculation of basal energy Expenditure (BEE) applying Harris-Benedict's equation (HB). The correlation between the REE calculation using indirect calorimetry and that of BEE using Harris-Benedict (r = 0.7567) did not give a correction factor, applied to the Harris-Benedict formula) (REE by IC/BEE), which was uniform for all patients, oscillating as it did between 1.0 and 1.8. We found no correlation between REE by IC and that calculated using the modified Fick method, nor between the modified Fick method and BEE as calculated by Harris-Benedict. Our conclusion is that, with the IC method as reference to evaluate energy use, the Harris-Benedict calculation appears to be more reliable than that using the modified Fick equation and that, in the group of patients studied, and given the individual variations in the REE ratio calculated by IC and the BEE calculated by HB, we were unable to find a suitable correction factor for them all. IC is therefore the ideal method for evaluating energy use in critical patients in the ICU.