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J Sanchis

Publications and source records attributed to J Sanchis.

At least 73 records · Page 4Linked to original sources
PubMed1997

[Application of clinical guidelines in the management of pleural effusion].

To analyze compliance with recommendations on the diagnosis and treatment of pleural effusion (PE), we conducted a retrospective study of 60 consecutive patients with PE. Thirty had been treated on the internal medicine ward (IM) and 30 had been cared for in the pneumology unit (P). Twelve variables were studied: 3 reflected the efficacy of medical intervention and 9 were related to diagnostic and therapeutic procedures as recommended by the American Thoracic Society and the American College of Physicians. PE was generally managed in accordance with the aforementioned guidelines. However, a number of unnecessary analytical tests were performed on pleural liquid from the first thoracocentesis. Although IM patients were comparable to P ward patients as to age, sex and concurrent chronic disease, the mean hospital stay was shorter for P ward patients (16 days versus 18 days in the IM ward, p < 0.05), and the percentage for whom an etiological diagnosis had been achieved upon discharge was higher in the P group (56% of P patients versus 26% of IM patients, p < 0.002). More P group patients than IM patients were followed up after discharge (83% versus 40%, respectively; p < 0.001). There were no significant differences in the remaining variables. Within the limitations of any retrospective study, these results allow us to conclude that PE is generally managed in accordance with international guidelines at our hospital and that diagnostic efficacy is greater on the pneumology ward, where mean stay is shorter.

Aged↗
PubMed1997

[Maximum static respiratory pressures in adults. The reference values for a Mediterranean Caucasian population].

The aim of this study was to establish reference values for PImax and PEmax for the Mediterranean adult population. Male and female individuals between 18 and 83 years old meeting the criteria for consideration as references and residing in the metropolitan area of Valencia were assigned by decades to six subgroups, each containing at least 20 men and 20 women. PEmax was obtained from the point of maximum expiration (residual volume) and PImax was the point of maximum inspiration (total lung capacity). The cohort, which finally included 264 subjects (129 men and 135 women), was separated a priori by sex for data analysis. The following types of variables were studied: sociological (employment, educational level and exercise), biometric (age, height and weight) and spirometric results. A linear correlation analysis was performed for each pair of variables and a Kolmogorov-Smirnov test of normality was performed. In order to check the accuracy of PImax and PEmax readings, intra-individual variability was determined by performing three consecutive procedures over 3 days in 39 randomly selected individuals (18 men and 21 women). Significant inter-day and inter-test effects for respiratory pressures were thus ruled out. Predictive equations were worked out using a simple linear model including all predictive variables and eliminating weaker variables in a stepwise manner. Mathematical goodness of fit was assessed by a coefficient for multiple determinations (R2); also determined were the estimated standard error and statistical significance. We also compared observed and estimated values and the behavior of residual values in terms of their independence, normality and homoscedasticity. Reference limits were established by defining percentiles. The equations finally arrived at for men were as follows: PImax (-cmH2O) - 1.03 x Age + 0.59 x Weight + 133.07, PEmax (cmH2O) - 1.31 x Age + 263.12. The equations for women were PImax (-cmH2O) - 0.64 x Age + 125.18, PEmax (cmH2O) - 0.57 x Age + 0.65 x Weight + 116.26. Agreement with the usual references (the Black and Hyatt equations) was analyzed.

Adult↗
PubMed1997

[Health workers' knowledge and skills regarding the use of the Turbuhaler inhaler].

The aim of this study was to evaluate health care workers' theoretical knowledge and skill in managing the dry powder Turbuhaler. We studied 118 individuals in three groups: 50 nurses, 34 medical residents and 34 staff physicians. Theoretical knowledge was evaluated by a questionnaire specifically designed for the purpose. Skill in managing the device was analyzed by evaluating a practical demonstration of the inhaling technique generally recommended, using a placebo inhaler. Six percent of staff physicians, 3% of the residents and 2% of the nurses answered the theoretical questionnaire correctly. Twenty-one percent of the staff physicians, 15% of the residents and 6% of the nurses inhaled correctly. However, when skill in managing the inhaler was evaluated against the maneuvers recommended by the manufacturer (which do not oblige exhaling before inhaling through the device and then holding the breath), there was significant improvement: 41% of the staff physicians, 23% of the residents, and 20% of the nurses inhaled correctly. We can conclude by saying that: a) our health care workers' general knowledge about how to handle the Turbuhaler device is deficient; b) the proportion of correct inhalation maneuvers observed doubles when these are assessed according to the manufacturer's recommendations, and c) health care workers should receive specific training in the inhalation techniques required for using the various devices usually prescribed.

Clinical Competence↗
PubMed1997

Are double potentials markers of a specific zone of the atrioventricular junction in the isolated rabbit heart?

A study is made of the characteristics of the atrial potentials recorded in the Koch triangle and its proximity, their variations on modifying the site of cardiac pacing, and their usefulness as markers of a distinct zone of the AV junction. In 12 isolated and perfused rabbit heart preparations an analysis was made of the endocardial atrial electrograms recorded with a multiple electrode positioned in the AV junction. The electrograms were obtained during spontaneous rhythm and on pacing at the crista terminalis (CT), interatrial septum (IAS), left atrium, and right ventricle. Double potentials were frequently obtained. On pacing at the CT, high-low double potentials (DP [H-L]) were more frequent (P < 0.05) in the low CT (11% +/- 4% of the electrodes) and posterior zone of the Koch triangle (6% +/- 5%), than in the IAS (1% +/- 2%) and anterior zone of the Koch triangle (2% +/- 3%). A similar tendency was observed either on pacing at the left atrium or during spontaneous rhythm. During pacing at the IAS the percentages of low-high double potentials (DP (L-H]) were significantly higher (P < 0.05) in the low CT (7% +/- 6%). DP (H-L) were of low sensitivity in indicating a given zone; maximum sensitivity was 61% in the low CT when pacing at the CT. DP (L-H) proved even less sensitive in indicating a given zone, though their specificity was greater in the low CT (91%) during pacing at the IAS. The specific zones in which the highest percentages of DP (H-L) or DP (L-H) are obtained depend on the site of cardiac pacing. On pacing at the IAS, DP (L-H) are more specific of the low CT. During pacing at both the CT and at the IAS, DP (H-L) sensitivity in indicating a given zone is low.

Action Potentials↗
PubMed1997

Modification of atrioventricular nodal electrophysiology by selective radiofrequency delivery on the anterior or posterior approaches.

An analysis was made in 14 isolated and perfused rabbit hearts of the electrophysiological effects of selective radiofrequency (RF) delivery in the anterior (group I, n = 7) or posterior zone (group II, n = 7) of the Koch triangle, with the aim of modifying atrioventricular nodal (AVN) conduction without suppressing 1:1 transmission. After opening the right atrium, RF was delivered (0.5 W) with a 1-mm diameter unipolar electrode positioned in the selected zone until a prolongation of no less than 15% was obtained in the Wenckebach cycle length (WCL). Before and after (30 min) RF, anterograde and retrograde AVN refractoriness and conduction were evaluated, stimulating from the crista terminalis (CT), the interatrial septum (IAS), and from the RV epicardium. After RF, the following percentage increments were observed in group I: AH(CT) = 36% +/- 9%, AH(IAS) = 38% +/- 11%, WCL(CT) = 28% +/- 8%, WCL(IAS) = 22% +/- 6%, functional refractory period (FRP) of the AVN(CT) = 13% +/- 11%, FRP-AVN(IAS) = 13% +/- 8%, retrograde WCL = 20% +/- 19%, and retrograde FRPVA = 13% +/- 16%. The increments observed in group II and the significances of the differences with respect to group I were: AH(CT) = 11% +/- 14% (P < 0.01), AH(IAS) = 19% +/- 32% (NS), WCL(CT) = 42% +/- 14% (P < 0.05), WCL(IAS) = 42% +/- 16% (P < 0.01), FRP-AVN(CT) = 28% +/- 28% (NS), FRP-AVN(LAS) = 21% +/- 19% (NS), retrograde WCL = 35% +/- 24% (NS), and retrograde FRP = 16% +/- 13% (NS). In both groups, the AH interval variations were not correlated with those of the rest of the parameters analyzed. Truncated nodal function curves suggestive of a dual AV nodal pathway were obtained in three experiments, though in only one of them was this observed under basal conditions. In the other two experiments, with dual AV nodal physiology only after RF (one from each group), AV nodal reentrant tachycardias were triggered with atrial extrastimulus at coupling intervals equal to or shorter than at those that cause a sudden lengthening of the AH interval, RF delivered in the anterior and posterior zones of the Koch triangle produced effects of different magnitude on the AH interval and Wenckebach cycle length. In the anterior zone the AH interval was prolonged to a greater extent, while in the posterior zone the effects were greater on the Wenckebach cycle length. No correlation existed between the variations in AH interval and Wenckebach cycle length, regardless of where RF was delivered. The evaluation of anterograde AV nodal refractoriness was similar when stimulating from the crista terminalis or from the interatrial septum. By delivering RF, it was possible to induce dual AV nodal physiology and reentrant tachycardias.

Animals↗
PubMed1997

Pleurodesis in malignant pleural effusions: a randomized study of tetracycline versus bleomycin.

Malignant pleural effusions are commonly managed with tube thoracostomy drainage followed by chemical pleurodesis. Both tetracycline and bleomycin have been shown to be effective for intrapleural instillation, although neither agent has definitively proved advantages over the other. The aim of the present study was to compare these two agents in terms of response rate and toxicity profile. A prospective, randomized trial was carried out in a single centre. Between May 1993 and January 1996, 62 evaluable patients with proved malignant pleural effusion were allocated to receive either intrapleural tetracycline (1.5 g) or bleomycin (60 mg) after the same drainage procedure. Demographic, clinical and fluid parameter data were comparable in both groups. Response was evaluated at 1, 3 and 6 months after pleurodesis. Mean survival and time to relapse did not differ between the two groups. No statistically significant differences were found in terms of efficacy at each evaluation time. Overall, 16 (52%) and 20 (64%) patients had a recurrence of pleural effusion during follow-up in the tetracycline and bleomycin arms, respectively. Fever was most common in bleomycin-treated patients (p=0.024) while pain was most frequent in the tetracycline arm (nonsignificant). Since no study agent was superior to the other in this trial, we suggest that economic costs, drug availability and medical skill should be considered in the choice of a sclerosing agent.

Adult↗
PubMed1997

Chylothorax complicating a thoracic aortic aneurysm.

Chylothorax is an uncommon condition, usually associated with advanced malignant disease or trauma to the thoracic duct. Idiopathic chylothorax and other diverse causes have been anecdotally reported. We describe a rare case of chylothorax, developing as a result of damage to the thoracic duct by a thoracic aortic aneurysm. Tetracycline pleurodesis was successful in controlling the chylous effusion.

Aged↗
PubMed1996

Stunned myocardium after thrombolytic treatment. Identification by dobutamine echocardiography and role of the residual stenosis in the infarction artery.

UNLABELLED: The aim of this study was to identify post-thrombolysis stunned myocardium using low dose (10 micrograms/kg/min) dobutamine echocardiography, and to elucidate the role of the residual stenosis in the infarction artery in wall motion recovery. Forty-seven consecutive patients treated with thrombolytic agents for a first non-complicated myocardial infarction were included. An early dobutamine echocardiogram was performed 7 +/- 2 days after thrombolysis to calculate a wall motion score index at baseline and with dobutamine. A late resting echocardiogram 36 +/- 7 days and a coronariography 41 +/- 8 days after thrombolysis were also performed. In 12 patients no baseline regional dysfunction was observed in the early echocardiogram (Group I), whereas 35 patients (Group II) presented regional dysfunction which improved with dobutamine in 11 cases (Group IIA), but not in 24 (Group IIB). Maximum creatine kinase peak was smaller in Group I (458 +/- 162, P < or = 0.01) and in Group IIA (931 +/- 593, P < or = 0.05) than in Group IIB (1547 +/- 886). Late resting echocardiogram was performed in 44 patients: all 12 from Group I, 10 from Group IIA and 22 from Group IIB; all patients from Group I persisted with normal wall motion, while the baseline score index improved in seven patients (70%) from Group IIA vs. three patients (14%) from Group IIB (P < or = 0.01). Quantitative angiographic parameters in the infarction artery failed to differentiate the subgroup of patients in whom wall motion improved in the late echocardiogram. By simple regression, smaller creatine kinase peak (P < or = 0.05) and a positive response to dobutamine in the early echocardiogram (P < or = 0.001) correlated with wall motion recovery, but the minimum lumen diameter in the infarction artery did not correlate; by multiple logistic regression, only a positive response to dobutamine in the early echocardiogram independently predicted late wall motion improvement (P < or = 0.001). CONCLUSIONS: (1) Low dose dobutamine echocardiography early after thrombolytic treatment identifies dysfunctional myocardium with potential late spontaneous improvement (stunned myocardium). (2) Myocardial stunning tends to occur in small infarctions. (3) Late wall motion improvement can occur despite severe residual stenosis in the infarction artery.

Anistreplase↗
PubMed1996

Modifications in the evolution of the dominant frequency in ventricular fibrillation induced by amiodarone, diltiazem, and flecainide. An experimental study.

In 22 anesthetized mongrel dogs, spectral methods were used to analyze the surface electrocardiogram (ECG) for the time course of the dominant frequency in ventricular fibrillation and its modifications under the influence of amiodarone, diltiazem, and flecainide. The ECG was recorded over 5 minutes after triggering ventricular fibrillation. Following A/D conversion and by applying the Fourier fast transform, the frequency spectrum of the signals was obtained. In group 1 (5 dogs), the ECGs were obtained without prior drug administration; group 2 (5 dogs) first received amiodarone, 5 mg/kg; group 3 (7 dogs) received diltiazem, 0.2 mg/kg; and group 4 (5 dogs) received flecainide, 2 mg/kg. All drugs were administered intravenously. An initial increase in the dominant frequency of ventricular fibrillation was found in the control group and also in the groups that received amiodarone, diltiazem, or flecainide. Diltiazem significantly increased the dominant frequency and diminished the arrhythmia-slowing process. Amiodarone and flecainide tended to diminish the dominant frequency.

Amiodarone↗
PubMed1996

[Compliance with the "recommendations SEPAR" on spirometry].

The objective of this study was to assess Spanish performance of spirometry and to determine the extent to which practice is in accordance with the 1985 SEPAR recommendations. To that end we formulated a questionnaire with 31 items in two sections, 10 covering basic aspects of compliance with necessary techniques and 21 general questions. The questionnaire was sent to all SEPAR members. One hundred eight responses were received. The results show that the typical spirometric measurement was forced expiration without a bronchodilator test by way of a pneumotacograph, with simultaneous representation of the flow/volume curve. Calibration, when performed, is done daily with a 3 1 syringe and atmospheric data are checked. Spirometric measurements are usually obtained by a registered nurse, who also collects anthropometric data directly from the patient. The patient is usually seated with the nose occluded. At least three and at most eight satisfactory readings are obtained. The criteria for starting and ending the maneuver and the reference values used are those recommended by SEPAR. The equipment is washed weekly with soap and water; calibrations and equipment incidences are not recorded. The level of compliance with 1985 SEPAR norms for forced spirometry is adequate with respect to some technical equipment questions but deficient on basic procedure and quality control.

Data Collection↗
PubMed1996

[A new device for measuring occlusion pressure].

Mouth pressure in the first 100 ms of inspiration with the airway occluded (P0.1) is an indirect measure of central airways activity. Few adequately validated devices are available on the market for measuring this variable automatically, impeding wider use of this measurement. Our aim was to determine the validity and precision of a new automatized manometer for measuring P0.1 and compare the device to the apparatus normally used in our laboratory. The newly manufactured device consisted of a semiconductor type pressure transduce connected to an analog-to-digital converter. The usual apparatus used was constructed in our laboratory from a Honewell transducer, an analog-to-digital card (Data Translation DT2801) for an IBM-compatible PC and a standard spread sheet program. Both devices recorded a continuous signal at a sample frequency of 100 Hz. To determine linearity, accuracy, sensitivity and precision, two columns of 5 and 25 cmH2O were used. For clinical assessment, 33 patients scheduled for lung function analysis were tested. Five measurements of P0.1 were performed on each. The sensitivity of the new device was 0.1 cmH2O; precision expressed as a variation coefficient was 0%, and linearity expressed as a correlation coefficient was r = 0.999 between the two columns. The mean difference between the two devices was 0.11 (0.46) cmH2O (p < 0.0001). Analysis of concordance confirmed a reading bias for the new device in comparison with the usual one, although the difference was not clinically significant (0.08 to 0.14 cmH2O). We conclude that the new device gives good results and its availability on the market may allow more frequent clinical application of occlusion pressure measurement.

Bite Force↗
PubMed1996

Assessment of chlorine exposure in swimmers during training.

The presence of a high prevalence of bronchial hyperresponsiveness and asthma-like symptoms in swimmers has been recently reported. Chlorine, a strong oxidizing agent, is an important toxic gas that the swimmer can breath during swimming. Measurements of the chlorine concentration at the breathing level (< 10 cm) were obtained randomly during five nonconsecutive days in four different swimming pool enclosures. The mean level in all the swimming pools was 0.42 +/- 0.24 mg.m-3, far below the threshold limited value (TLV) of 1.45 mg.m-3 for the work places for a day of work (8 h). The TLV could be reached and even exceeded if we consider the total amount of chlorine that a swimmer inhales in a daily training session of 2 h (4-6 g) compared with a worker during 8 h at the TLV (4-7 g). Low correlation was observed with the number of swimmers in the swimming pool during the measurements (0.446) and other variables as the water surface area of the pool, volume of the enclosure, and the chlorine-addition system in the swimming pool. A low turnover rate in the air with an increase of chlorine levels through the day (P < 0.05) was observed in all pools. The concentration of chlorine in the microenvironment where the swimmer is breathing is below the TLV concentration limit, but nevertheless results in a high total volume of chlorine inhaled by the swimmers in a given practice session. The possible role of chlorine in producing respiratory symptoms in swimmers needs further investigation.

Chlorine↗
PubMed1996

Recovery curve and concealed conduction in the His-Purkinje system of the rabbit heart: effects of radiofrequency modification of the low AV junction.

UNLABELLED: The aim of this study was to analyze the recovery curve and concealed conduction in the normal His-Purkinje system and after delivering radiofrequency current in the low AV junction, in the perfused rabbit heart. Twenty-one rabbit hearts were studied. Radiofrequency current (5 W) was delivered in the low AV junction to induce an incomplete His-Purkinje AV block (HV prolongation with 1:1 AV conduction); this was achieved in 9 experiments (Group I), while 12 experiments developed a complete block (Group II). Atrial stimulation was performed in both Groups at baseline, and in Group I after radiofrequency delivery, as follows: (1) pacing at increasing rates to determine the His-Purkinje AV block cycle length; (2) atrial extrastimulus test (A1A2) to calculate the His-Purkinje effective refractory period and the fitting of the recovery curve (H1H2 vs H2V2) to the exponential equation delta HV = a.e(-b)x(H1H2); (3) concealed conduction protocol (in 15 experiments) consisting of an atrial extrastimulus test with an interposed beat (A1-A0-A2) at a fixed A1A0 coupling interval. The baseline recovery curve fitted an exponential equation in 17 experiments (with a 93% +/- 42% maximum H2V2 increase at the shortest H1H2), but did not in 4 experiments (the maximum H2V2 increase being only 22% +/- 7%). Radiofrequency application prolonged the HV interval (25 +/- 6 ms vs 46 +/- 16 ms; P = 0.001) and His-Purkinje effective refractory period (167 +/- 28 ms vs 217 +/- 57 ms; P = 0.02). The percentage increment was greater for HV than for refractory period (99% +/- 65% vs 35% +/- 32%; P = 0.02); however, the increment of the His-Purkinje block cycle length (77% +/- 74%) only correlated with that of the refractory period (r = 0.95; P = 0.0001). The recovery curve after radiofrequency delivery fitted an exponential equation in all experiments, showing a rightward shift expressed by an increment of the constant ln a (2.7 +/- 1.9 vs 5.5 +/- 5.5; P = 0.02). Concealed conduction appeared in only three experiments at baseline. After radiofrequency, however, it was observed in all experiments, producing a rightward shift of the recovery curve and an ln a increase (2.87 +/- 1.2 vs 9.9 +/- 2.7; P = 0.0001). When Ho was conducted, the curve rightward shift and ln a increase (26 +/- 7.5; P = 0.0001) were greater. CONCLUSION: (1) His-Purkinje physiology, as in AV nodal physiology, can be described by a recovery curve that fits an exponential equation, especially if conduction becomes depressed with radiofrequency current. (2) Radiofrequency application in the low AV junction modifies His-Purkinje conduction more than refractoriness, though the refractoriness increase determines the degree of block at fast atrial rates. (3) Concealed conduction is uncommon in the normal His-Purkinje system during atrial pacing, but very frequent after modifying the low AV junction with radiofrequency current.

Animals↗
PubMed1996

Pain during arterial puncture.

STUDY OBJECTIVE: To quantify the level of pain reported by patients during arterial puncture with or without local anesthesia, and to compare the results with levels reported for venous puncture. DESIGN: Double-blind study of puncture with and without local anesthesia. SETTING: Pulmonary function laboratory, department of pneumology. PATIENTS: We studied 270 consecutive patients undergoing arterial puncture divided into two groups. In group A (n = 210), we assessed level of pain with and without local anesthesia and with placebo. In group B (n = 60), we compared pain of arterial and venous puncture. INTERVENTIONS: The arterial puncture was performed in the radial artery; venous puncture was in the median basilic vein. MEASUREMENTS AND RESULTS: The pain was quantified on a visual analog scale (10 cm). Mean level of pain for all arterial punctures without anesthesia or placebo was slight to moderate (3.01 +/- 1.94 cm). Subcutaneous anesthetic infiltration before arterial puncture significantly reduced pain by more than 50%, to 1.50 +/- 1.54 cm, a level that was significantly lower than the pain level reported after conventional venous puncture (1.80 +/- 1.10 cm). The pain reported by patients who received no anesthesia was not significantly different (p = 0.45) from that perceived by those who received subcutaneous infiltration of saline solution (placebo). CONCLUSIONS: Arterial puncture with prior infiltration of local anesthetic is the least painful procedure among those studied. Use of local anesthesia is indicated whenever conventional arterial puncture is required.

Anesthesia, Local↗