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1.
Ann Behav Med ; 52(8): 621-632, 2018 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-30010703

RESUMEN

Background: Maintaining a healthy lifestyle in adulthood has been shown to significantly reduce cardiovascular disease risk. Increasing evidence suggests that behavioral risk factors for cardiovascular disease are established in childhood; however, limited research has evaluated whether childhood psychological factors play a role. Purpose: To evaluate the association between childhood psychological distress and young to mid adulthood healthy lifestyle. Methods: Using prospective data from the 1958 British Birth Cohort, we assessed whether psychological distress in childhood (captured by internalizing and externalizing symptoms at ages 7, 11, and 16 years) predicted healthy lifestyle at ages 33 (N = 10,748) and 42 (N = 9,581) years. Healthy lifestyle was measured using an index previously demonstrated to predict cardiovascular disease, consisting of five components: absence of smoking, moderate alcohol consumption, regular physical activity, healthy diet, and ideal body weight. Results: Few participants (3.8% at age 33 years and 2.8% at age 42 years) endorsed all five healthy lifestyle components. Linear regression models, adjusting for potential child- and family-level confounders, revealed that higher distress levels in childhood were negatively associated with healthy lifestyle at age 33 years (ß = -0.11, SE = 0.01, p < .001) and 42 years (ß = -0.13, SE = 0.01, p < .001). Higher distress was also associated with significantly lower odds of endorsing each lifestyle component, except physical activity, at both ages. Additional analyses indicated that childhood distress levels were highest among those whose lifestyle scores were low at age 33 and further declined between ages 33 and 42. Conclusions: Psychological distress in childhood may indicate children at risk of less healthy lifestyle practices later in life. Although our findings are preliminary, psychological distress may also provide an important target for public health interventions aimed at preventing cardiovascular disease.


Asunto(s)
Adultos Sobrevivientes de Eventos Adversos Infantiles/psicología , Enfermedades Cardiovasculares/prevención & control , Estilo de Vida Saludable , Adulto , Factores de Edad , Estudios de Cohortes , Femenino , Humanos , Masculino , Estudios Prospectivos
2.
Psychol Med ; 47(8): 1370-1378, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28052776

RESUMEN

BACKGROUND: Prior studies suggest that post-traumatic stress disorder (PTSD) is associated with elevated cardiovascular disease (CVD) risk, but effects of duration and remission of PTSD symptoms have rarely been evaluated. METHOD: We examined the association of time-updated PTSD symptom severity, remission and duration with incident CVD risk (552 confirmed myocardial infarctions or strokes) over 20 years in 49 859 women in the Nurses' Health Study II. Among women who reported trauma on the Brief Trauma Questionnaire, PTSD symptoms, assessed by a screener, were classified by symptom severity and chronicity: (a) no symptoms, (b) 1-3 ongoing, (c) 4-5 ongoing, (d) 6-7 ongoing, (e) 1-3 remitted, (f) 4-7 remitted symptoms. Inverse probability weighting was used to estimate marginal structural logistic regression models, adjusting for time-varying and time-invariant confounders. RESULTS: Compared with women with no trauma exposure, women with trauma/no PTSD [odds ratio (OR) 1.30, 95% confidence interval (CI) 1.03-1.65] and women with trauma/6-7 symptoms (OR 1.69, 95% CI 1.08-2.63) had elevated risk of CVD; women with remitted symptoms did not have elevated CVD risk. Among women exposed to trauma, every 5 additional years of PTSD symptomology was associated with 9% higher CVD incidence compared with women with trauma/no PTSD. CONCLUSIONS: The findings suggest that alleviating PTSD symptoms shortly after onset may attenuate CVD risk.


Asunto(s)
Infarto del Miocardio/epidemiología , Trastornos por Estrés Postraumático/epidemiología , Trastornos por Estrés Postraumático/fisiopatología , Accidente Cerebrovascular/epidemiología , Adulto , Enfermedad Crónica , Femenino , Humanos , Estudios Longitudinales , Persona de Mediana Edad , Remisión Espontánea , Riesgo , Factores de Tiempo
3.
Psychol Med ; 47(2): 209-225, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27697083

RESUMEN

Post-traumatic stress disorder (PTSD) has been declared 'a life sentence' based on evidence that the disorder leads to a host of physical health problems. Some of the strongest empirical research - in terms of methodology and findings - has shown that PTSD predicts higher risk of cardiometabolic diseases, specifically cardiovascular disease (CVD) and type 2 diabetes (T2D). Despite mounting evidence, PTSD is not currently acknowledged as a risk factor by cardiovascular or endocrinological medicine. This view is unlikely to change absent compelling evidence that PTSD causally contributes to cardiometabolic disease. This review suggests that with developments in methods for epidemiological research and the rapidly expanding knowledge of the behavioral and biological effects of PTSD the field is poised to provide more definitive answers to questions of causality. First, we discuss methods to improve causal inference using the observational data most often used in studies of PTSD and health, with particular reference to issues of temporality and confounding. Second, we consider recent work linking PTSD with specific behaviors and biological processes, and evaluate whether these may plausibly serve as mechanisms by which PTSD leads to cardiometabolic disease. Third, we evaluate how looking more comprehensively into the PTSD phenotype provides insight into whether specific aspects of PTSD phenomenology are particularly relevant to cardiometabolic disease. Finally, we discuss new areas of research that are feasible and could enhance understanding of the PTSD-cardiometabolic relationship, such as testing whether treatment of PTSD can halt or even reverse the cardiometabolic risk factors causally related to CVD and T2D.


Asunto(s)
Enfermedades Cardiovasculares/etiología , Diabetes Mellitus Tipo 2/etiología , Trastornos por Estrés Postraumático/complicaciones , Humanos
4.
Psychol Med ; 46(15): 3105-3116, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27534802

RESUMEN

BACKGROUND: Post-traumatic stress disorder (PTSD) has been linked to hypertension, but most research on PTSD and hypertension is cross-sectional, and potential mediators have not been clearly identified. Moreover, PTSD is twice as common in women as in men, but understanding of the PTSD-hypertension relationship in women is limited. We examined trauma exposure and PTSD symptoms in relation to incident hypertension over 22 years in 47 514 civilian women in the Nurses' Health Study II. METHOD: We used proportional hazards models to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for new-onset hypertension (N = 15 837). RESULTS: PTSD symptoms assessed with a screen were modestly associated with incident hypertension in a dose-response fashion after adjusting for potential confounders. Compared to women with no trauma exposure, women with 6-7 PTSD symptoms had the highest risk of developing hypertension (HR 1.20, 95% CI 1.12-1.30), followed by women with 4-5 symptoms (HR 1.17, 95% CI 1.10-1.25), women with 1-3 symptoms (HR 1.12, 95% CI 1.06-1.18), and trauma-exposed women with no symptoms (HR 1.04, 95% CI 1.00-1.09). Findings were maintained, although attenuated, adjusting for hypertension-relevant medications, medical risk factors, and health behaviors. Higher body mass index and antidepressant use accounted for 30% and 21% of the PTSD symptom-hypertension association, respectively. CONCLUSIONS: Screening for hypertension and reducing unhealthy lifestyle factors, particularly obesity, in women with PTSD may hold promise for offsetting cardiovascular risk.


Asunto(s)
Hipertensión/epidemiología , Trauma Psicológico/epidemiología , Trastornos por Estrés Postraumático/epidemiología , Adulto , Antidepresivos/uso terapéutico , Índice de Masa Corporal , Estudios de Cohortes , Femenino , Humanos , Incidencia , Estudios Longitudinales , Persona de Mediana Edad , Obesidad/epidemiología , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad
5.
J Am Coll Cardiol ; 36(4): 1328-35, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11028491

RESUMEN

OBJECTIVES: We studied the incidence of myocardial injury in aneurysmal subarachnoid hemorrhage (SAH) using the more sensitive cardiac troponin I (cTnI) assay, correlated changes in cTnI with creatine kinase, MB fraction (CK-MB), myoglobin, and catecholamine metabolite assays, and examined the predictive value of changes in cTnI for myocardial dysfunction. BACKGROUND: Myocardial injury in aneurysmal SAH as evidenced by elevated CK-MB fraction has been reported. Little published data exist on the value of cTnI measurements in aneurysmal SAH. METHODS: Thirty-nine patients were studied for seven days. Clinical cardiovascular assessment, electrocardiographic (ECG), echocardiography, cTnI, CK, CK-MB and CK-MB index, myoglobin and 24-h urinary catecholamine assays were performed in all patients. The ECG abnormalities were defined by the presence of ST-T changes, prolonged QT intervals, and arrhythmias. An abnormal echocardiogram was defined by the presence of wall-motion abnormalities and a reduced ejection fraction. The severity of SAH was graded clinically and radiologically. RESULTS: Eight patients demonstrated elevations in cTnI (upper limit of normal is 0.1 microg/liter with the immunoenzymatic assay and 0.4 microg/liter with the sandwich immunoassay), while five had abnormal CK-MB levels (upper limit of normal is 8 microg/liter). Patients with more severe grades of SAH were more likely to develop a cTnI leak (p < 0.05). Patients with cTnI elevations were more likely to demonstrate ECG abnormalities (p < 0.01) and manifest clinical myocardial dysfunction (p < 0.01) as evidenced by the presence of a gallop rhythm on auscultation and clinical or radiological evidence of pulmonary edema as compared to those with CK-MB elevations. The sensitivity and specificity of cTnI to predict myocardial dysfunction were 100% and 91%, respectively, whereas the corresponding figures for CK-MB were 60% and 94%, respectively. Elevations in myoglobin levels (upper limit of normal <70 microg/liter) and urinary catecholamine metabolites (urinary vanilmandelate/creatinine ratio upper limit of normal, 2.6) are a nonspecific finding. CONCLUSIONS: Measurements of cTnI reveal a higher incidence of myocardial injury than predicted by CK-MB in aneurysmal SAH, and elevations of cTnI are associated with a higher incidence of myocardial dysfunction. Thus, cTnI is a highly sensitive and specific indicator of myocardial dysfunction in aneurysmal SAH.


Asunto(s)
Cardiomiopatías/sangre , Miocardio/metabolismo , Hemorragia Subaracnoidea/sangre , Troponina I/sangre , Adulto , Anciano , Biomarcadores/sangre , Biomarcadores/orina , Cardiomiopatías/diagnóstico , Cardiomiopatías/etiología , Cardiomiopatías/metabolismo , Catecolaminas/orina , Creatina Quinasa/sangre , Ecocardiografía , Electrocardiografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mioglobina/sangre , Pronóstico , Sensibilidad y Especificidad , Índice de Severidad de la Enfermedad , Hemorragia Subaracnoidea/complicaciones
7.
Am J Respir Crit Care Med ; 149(5): 1142-8, 1994 May.
Artículo en Inglés | MEDLINE | ID: mdl-8173754

RESUMEN

Platelet-activating factor (PAF) may be a major mediator of asthma and bronchial hyperreactivity through its many proinflammatory actions. Specific antagonism of PAF might offer an alternative anti-inflammatory treatment to inhaled corticosteroids. To test this, we have studied the effect of an orally active PAF antagonist, WEB 2086, on the inhaled steroid requirements of symptomatic atopic asthmatics in a double-blind randomized placebo-controlled parallel group study. The inhaled corticosteroid dose required for symptomatic control of asthma was established and further steroid reduction was attempted after treatment with WEB 2086 40 mg three times daily for 12 wk. Of 106 patients recruited, 68 entered the treatment phase and 65 completed 6 wk of treatment. The mean daily corticosteroid dose (SE) at study entry was 1,257 (75) micrograms which was reduced by 323 (66) micrograms during the run-in period without loss of symptomatic control. A further 416 (57) micrograms reduction in inhaled corticosteroid dosage was possible during the treatment phase but this was almost identical in the WEB 2086 and placebo-treated groups, amounting to 353 (92) and 481 (65) micrograms/day respectively (not significant [NS]). Rate of relapse following corticosteroid reduction was a continuous variable and relapse occurred at different times depending on the variable used to define it. Time to relapse measured by an increase in symptoms correlated with disease duration (r = 0.41, p < 0.01) and with the dose of inhaled corticosteroid at study entry (r = 0.36, p < 0.01) but no other measured variable predicted the time to relapse.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Asma/tratamiento farmacológico , Azepinas/administración & dosificación , Factor de Activación Plaquetaria/antagonistas & inhibidores , Triazoles/administración & dosificación , Administración por Inhalación , Administración Oral , Adolescente , Adulto , Anciano , Albuterol/administración & dosificación , Asma/fisiopatología , Beclometasona/administración & dosificación , Método Doble Ciego , Quimioterapia Combinada , Femenino , Humanos , Masculino , Persona de Mediana Edad , Ápice del Flujo Espiratorio/efectos de los fármacos
8.
Thorax ; 46(9): 643-50, 1991 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1948793

RESUMEN

Prediction equations for normal lung function have been derived from tests on 179 healthy, non-smoking, white urban dwellers. The subjects, 96 women (height 1.46-1.77 m) and 83 men (height 1.61-1.96 m) aged 18-86 years, underwent measurements of spirometric flow and volume, multi-breath helium dilution lung volumes, and single breath carbon monoxide transfer factor and the single breath nitrogen washout test. Regression analysis using height, age, and weight as independent variables was used to provide predicted values for both sexes. Correlation coefficients were similar to those found in previous studies but normal ranges for spirometic measurements were narrower than in many previous studies, and spirometric flow and volume measurements were higher than those obtained in studies that included cigarette smokers, reflecting our more stringent criteria for selecting subjects and the newer standardised technical methods adopted. Multi-breath helium dilution values for total lung capacity were similar to those found in previous studies but the inspiratory vital capacity was larger and the residual volume reduced. Values for carbon monoxide transfer factor and the single breath nitrogen washout did not differ significantly from existing values. A complete set of lung function reference values and prediction equations for both sexes has been derived from a single population. The exclusion of cigarette smokers and subjects with respiratory symptoms has produced values that should have a greater sensitivity in the detection of mild lung disease.


Asunto(s)
Pulmón/fisiología , Población Urbana , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Envejecimiento/fisiología , Femenino , Volumen Espiratorio Forzado/fisiología , Humanos , Londres , Masculino , Persona de Mediana Edad , Valores de Referencia , Pruebas de Función Respiratoria/métodos , Factores Sexuales
9.
Respir Physiol ; 81(1): 87-98, 1990 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2218109

RESUMEN

In animals, tonic vagal activity from lung receptors provides a means by which changes in end-expiratory lung volume can influence respiratory timing. We wished to examine whether increasing the end-expiratory lung volume within the tidal volume range had a similar effect in man. In order to minimize behavioral influences on breathing, the study was performed in subjects during deep non-rapid eye movement sleep. Five laryngectomized subjects were chosen for the study since their permanent tracheal stomata allow simple, airtight connection to respiratory apparatus and avoided problems with glottic closure. During EEG-documented sleep, end-expiratory volume was increased by up to 350 ml with the addition of expiratory threshold loads of 1 to 10 cm H2O. End-expiratory volume increased linearly with expiratory pressure. Inspiratory and expiratory times (TI and TE) were not affected by increases in end-expiratory volume. Tidal volume (VT) was decreased such that end-inspiratory volume remained unchanged. The decrease in VT may result from a reduction in inspiratory muscle efficiency at a higher lung volume. The results of the study provide no evidence that tonic vagal afferent information from the lungs is important in controlling respiratory rhythm within the tidal volume range in man when behavioral control of breathing is minimized.


Asunto(s)
Pulmón/fisiología , Capacidad Pulmonar Total/fisiología , Adulto , Vías Aferentes/fisiología , Anciano , Humanos , Laringectomía , Pulmón/inervación , Masculino , Métodos , Persona de Mediana Edad , Sueño , Nervio Vago/fisiología
10.
Eur Respir J ; 2(9): 802-10, 1989 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2806503

RESUMEN

Cigarette smoke-induced emphysema is thought to involve reduction of antielastolytic capacity, resulting in elevated elastase activity and lung tissue damage. Peripheral lavage collected from ten asymptomatic subjects immediately before and 20 min after smoking two high tar cigarettes was analysed for neutrophil elastase (NE) inhibitory capacity (IC), alpha 1-proteinase inhibitor (PI) function, elastolytic activity and immunoreactive levels of PI and bronchial inhibitor (BI). The only change found was a small fall in mol immunoreactive PI/mol albumin after smoking (approximately 17%, p less than 0.05) which did not affect NEIC, since PI contributed less than 50% of the NEIC. There was often more NEIC than mol BI + functional PI, suggesting the presence of other NE inhibitors. Thoracic computerized tomography scans of eight of these subjects highlighted two with emphysematous regions of lung; lavage from these two subjects contained either undetectable BI or inactive BI and this suggests a protective role for BI in emphysema.


Asunto(s)
Pulmón/metabolismo , Neutrófilos/enzimología , Elastasa Pancreática/metabolismo , Enfisema Pulmonar/etiología , Inhibidores de Serina Proteinasa/metabolismo , Serpinas , Fumar/efectos adversos , Adulto , Albúminas/metabolismo , Líquido del Lavado Bronquioalveolar/análisis , Femenino , Humanos , Elastasa de Leucocito , Masculino , Enfisema Pulmonar/diagnóstico por imagen , Tomografía Computarizada por Rayos X , alfa 1-Antitripsina/metabolismo
11.
Am Rev Respir Dis ; 139(3): 653-8, 1989 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2923365

RESUMEN

Patients with interstitial lung disease (ILD) characteristically exhibit an increased ventilation and breathing frequency when awake. We wanted to see if these increases persisted during deep non-REM sleep. Using noninvasive techniques, we have quantified the pattern of breathing, arterial oxygen saturation, and transcutaneous PCO2 (PtcCO2) during standardized conditions of relaxed wakefulness and during Stage 4 (S4) sleep in eight patients with ILD and eight age-matched normal control subjects. The patients were given supplemental oxygen in order to prevent hypoxic ventilatory stimulation. The data were compared between the two groups during each of these states and also between states within each group. During wakefulness in the patients, respiratory frequency (f) and PtcCO2 were higher (p less than 0.001 and p less than 0.05, respectively) and inspiratory time (TI) and expiratory time (TE) were shorter (p less than 0.05 and p less than 0.001, respectively) than in the normal subjects. However, during S4 sleep, there were no significant differences between groups. Comparing wakefulness with S4 sleep: in the normal subjects during sleep, f and PtcCO2 were increased (p less than 0.01 and p less than 0.05, respectively), TE was shortened (p less than 0.01), and ventilation (VI) was unchanged. In contrast, in the patients, f decreased (p less than 0.001), TE lengthened (p less than 0.01), VI decreased (p less than 0.05), and the rise in PtcCO2 seen in the normal subjects during sleep did not occur.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Fibrosis Pulmonar/fisiopatología , Respiración , Sueño/fisiología , Anciano , Aire , Humanos , Máscaras , Persona de Mediana Edad , Oxígeno , Descanso , Vigilia
12.
Eur Respir J ; 1(9): 792-800, 1988 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3229477

RESUMEN

This study describes two new techniques of lung lavage which selectively remove material from the central airways, or from the lung below the seventh generation. Bronchograms confirmed that discrete regions of the lung were washed by central lavage (CL; maximum airway diameter approximately 6.5 mm) and peripheral lavage (PL; maximum airway diameter approximately 1.3 mm), and that both could be clearly distinguished from conventional bronchoalveolar lavage (BAL). These techniques were used to establish whether or not large-airway proteins made a major contribution to the protein profile of BAL. Twenty consecutive patients undergoing routine fibreoptic bronchoscopy were investigated. More bronchial mucus proteinase inhibitor per unit albumin and per unit total measured antiproteinase was present in CL than PL or BAL. In contrast alpha 1-proteinase inhibitor per unit albumin and as a percentage of total measured antiproteinase was lower in CL than in other lavage types. There were no differences in elastase activity, irrespective of the way in which the data were expressed. As no differences were found between BAL and PL for any of the variables measured, it was concluded that in the subjects studied the contribution of CL proteins to BAL was minimal.


Asunto(s)
Líquido del Lavado Bronquioalveolar/análisis , Elastasa Pancreática/análisis , Inhibidores de Proteasas/análisis , Adulto , Anciano , Neoplasias de los Bronquios/diagnóstico , Líquido del Lavado Bronquioalveolar/enzimología , Femenino , Humanos , Enfermedades Pulmonares Obstructivas/diagnóstico , Masculino , Mesotelioma/diagnóstico , Persona de Mediana Edad , Neumonía/diagnóstico , Albúmina Sérica/análisis
13.
Respir Physiol ; 73(2): 145-54, 1988 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-3420318

RESUMEN

To determine whether the Hering-Breuer inflation reflex could be demonstrated in the presence and absence of behavioral influences on breathing, lung inflation was performed via the tracheal stoma in eleven laryngectomized subjects: seven seated at rest with their eyes closed and six recumbent during their deepest non-rapid eye movement sleep. Laryngectomized subjects were chosen for study since their permanent tracheal stoma and absence of a glottis abolished the sensation of inflation in the upper airways, avoided problems with glottic closure and allowed simple, airtight connection to respiratory apparatus. At rest awake, inflation volumes of 500-3050 ml caused no reproducible apnea. During EEG-documented sleep, the inflation reflex was tested on 75 occasions using inflation volumes of 540-2100 ml. On the 66 occasions not associated with subject arousal inflations exceeding approximately 1 L produced apnea terminated by inspiration; greater volumes gave longer apneas. At the end of the study the subjects were woken and retested; no reproducible apnea was found. We conclude that the Hering-Breuer inflation reflex can be demonstrated above the resting tidal volume range in adult man in the absence of the behavioral control of breathing.


Asunto(s)
Pulmón/fisiología , Respiración , Sueño/fisiología , Vigilia/fisiología , Humanos , Laringectomía , Traqueostomía
14.
Clin Sci (Lond) ; 74(3): 275-81, 1988 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-3345636

RESUMEN

1. The ventilatory response to maximal incremental exercise and the accompanying sensation of breathlessness were studied after the inhalation of 0.9% sodium chloride (saline) and 5% bupivacaine aerosols in six patients with interstitial lung disease. 2. The adequacy of airway anaesthesia induced by bupivacaine aerosol was confirmed by the absence of the cough reflex to 5% citric acid aerosol on completion of exercise. 3. All subjects first performed a trial exercise test to familiarize them with the procedure and to assess the degree of arterial oxygen desaturation on exercise. In subsequent tests, supplementary oxygen was given to maintain the saturation at 95% or above. 4. Airway anaesthesia had no effect on the ability to perform exercise as assessed by maximum workload, CO2 production or heart rate. No significant changes were seen on the pattern of breathing, minute ventilation or end-tidal PCO2 on exercise. There was, however, a small but statistically significant increase in ventilation related to CO2 production (VE/VCO2) at the end of exercise. 5. There was a tendency for breathlessness to be increased by airway anaesthesia but this did not reach statistical significance. 6. These results provide no evidence that vagal afferent activity is responsible for the abnormal ventilatory response to exercise in patients with interstitial lung disease. The perception of breathlessness in these patients was not diminished by anaesthesia of the airway.


Asunto(s)
Bupivacaína/administración & dosificación , Pulmón/fisiopatología , Esfuerzo Físico , Fibrosis Pulmonar/fisiopatología , Respiración , Aerosoles , Anciano , Prueba de Esfuerzo , Humanos , Pulmón/efectos de los fármacos , Masculino , Persona de Mediana Edad , Pruebas de Función Respiratoria
16.
J Appl Physiol (1985) ; 63(6): 2286-92, 1987 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-3125140

RESUMEN

The effect of local anesthetic aerosol inhalation on the ventilatory response and the sensation of breathlessness to CO2 rebreathing was studied in seven healthy male subjects with permanent tracheal stomas after laryngectomy for carcinoma. Inhalation of bupivacaine aerosol sufficient to abolish the cough reflex to mechanical probing below the carina increased the ventilatory response to CO2 in six of seven subjects compared with saline control. This was achieved by an increase in both respiratory frequency (f) and tidal volume (VT) in four subjects, f in one subject, and VT in one subject. All subjects reported that they were more breathless on rebreathing after bupivacaine aerosol. The six subjects who recorded breathlessness with a visual analog scale (VAS) indicated its onset at a lower minute ventilation (VE) and gave higher VAS scores for equivalent levels of VE after threshold. We conclude that the enhanced CO2 sensitivity and breathlessness on rebreathing after airway anesthesia results from altered lower airway receptor discharge.


Asunto(s)
Anestesia por Inhalación/efectos adversos , Bupivacaína/efectos adversos , Dióxido de Carbono/fisiología , Disnea/etiología , Hipercapnia/etiología , Laringectomía , Anciano , Volumen Espiratorio Forzado , Capacidad Residual Funcional , Humanos , Masculino , Persona de Mediana Edad , Volumen de Ventilación Pulmonar , Capacidad Vital
18.
Respir Physiol ; 67(2): 159-70, 1987 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-3823655

RESUMEN

To determine whether local anesthetic aerosol could selectively block a reflex thought to originate from the alveoli, two small particle bupivacaine aerosols (mass median diameters 1.0 and 1.7 micron) were administered on separate occasions to spontaneously breathing anesthetized dogs. Both aerosols resulted in a small but statistically significant increase in VT and one produced an increase in f. The pulmonary chemoreflex to right heart injection of capsaicin, the cough reflex and the Hering-Breuer inflation reflex were unaffected. The ability of a large particle aerosol (mass median diameter 4.8 micron) to block these reflexes was also assessed. This aerosol produced a progressive slowing and deepening of breathing which was maximal after 20 min of aerosol inhalation. Ten min of this aerosol attenuated the pulmonary chemoreflex and abolished the cough and inflation reflexes; 20 min abolished all reflexes. These had recovered by about 1 h after aerosol. Intravenous bupivacaine had no effect on breathing or any reflex. We conclude that a local anesthetic aerosol can block reflexes arising from the alveoli, but not selectively.


Asunto(s)
Anestésicos Locales , Bupivacaína , Bloqueo Nervioso , Alveolos Pulmonares/fisiología , Reflejo/fisiología , Fenómenos Fisiológicos Respiratorios , Aerosoles , Animales , Perros , Inyecciones Intravenosas , Tamaño de la Partícula
19.
Eur J Respir Dis Suppl ; 153: 93-102, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-3322871

RESUMEN

Increased pulmonary proteolytic (elastolytic) activity is thought to be the primary cause of emphysema and may also play a rôle in the pathology of bronchitis. These diseases are common amongst tobacco smokers. Serum-derived alpha 1-proteinase inhibitor (alpha 1PI) and locally produced protease inhibitors normally protect the pulmonary epithelium from proteolytic attack, but tobacco smoke can inactivate these antiproteases by oxidative and non-oxidative mechanisms. Bronchoalveolar lavage fluid (BALF) samples lung surface components and most studies show that there is elevated elastolytic activity in smokers' BALF. Whether antiproteolytic capacity is reduced in these samples remains debatable. A selective lavage technique is described which independently samples central and peripheral epithelium from the same subject. Analysis demonstrates a protease-antiprotease imbalance which can differ in central and peripheral lavage and which could be significant in the development of obstructive airways disease. Therapeutic approaches include augmenting antiprotease potential using genetically engineered, oxidant-resistant alpha 1PI or synthetic peptide inhibitors.


Asunto(s)
Péptido Hidrolasas/metabolismo , Inhibidores de Proteasas/metabolismo , Sistema Respiratorio/enzimología , Enfermedades Respiratorias/tratamiento farmacológico , Fumar , Epitelio/enzimología , Humanos , Pulmón/enzimología , Enfermedades Respiratorias/enzimología , Irrigación Terapéutica/métodos
20.
Clin Sci (Lond) ; 71(5): 519-26, 1986 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-3769402

RESUMEN

The respiratory and cardiovascular effects of capsaicin injection into the superior vena cava and an arm vein were studied in three normal subjects. No changes were seen in tidal volume, inspiratory time or expiratory time after capsaicin injection. Instantaneous heart rate, systolic blood pressure and diastolic blood pressure remained unchanged. Central and peripheral intravenous injections of capsaicin but not control solution above a threshold of 0.5 micrograms/kg produced dose-dependent sensations sequentially in the chest, face, rectum and extremities. The chest sensation, a 'raw, burning' feeling, occurred 3-4 s after central capsaicin injection. No subject reported feeling breathless. In one subject the maximum tolerable dose of capsaicin (4 micrograms/kg) produced paroxysmal coughing 3.9 s after a central injection. In two of the subjects capsaicin injection was repeated after inhalation of a 5% bupivacaine aerosol (aerodynamic mass median diameter 4.8 micron), sufficient to block the cough reflex to a 5% citric acid aerosol. Prior inhalation of local anaesthetic aerosol abolished the chest sensation after capsaicin injection; the other sensations were unaffected. This study demonstrates that stimulation of receptors accessible from the pulmonary vascular bed does not evoke the pulmonary chemoreflex in conscious man but can produce coughing. It provides evidence for the existence of a nociceptive system of nerve endings in the lung parenchyma that can be blocked by inhaled local anaesthetic aerosol.


Asunto(s)
Capsaicina/farmacología , Hemodinámica/efectos de los fármacos , Respiración/efectos de los fármacos , Bupivacaína/farmacología , Capsaicina/administración & dosificación , Humanos , Inyecciones Intravenosas , Masculino
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