Cardiovascular effects of breath-hold diving at altitude.

Hypoxia, centralization of blood in pulmonary vessels, and increased cardiac output during physical exertion are the pathogenetic pathways of acute pulmonary edema observed during exposure to extraordinary environments. This study aimed to evaluate the effects of breath-hold diving at altitude, which exposes simultaneously to several of the stimuli mentioned above. To this aim, 11 healthy male experienced divers (age 18-52y) were evaluated (by Doppler echocardiography, lung echography to evaluate ultrasound lung B-lines (BL), hemoglobin saturation, arterial blood pressure, fractional NO (Nitrous Oxide) exhalation in basal condition (altitude 300m asl), at altitude (2507m asl) and after breath-hold diving at altitude.

Acute Pulmonary Edema in Healthy Subjects.

Healthy individuals may present with acute pulmonary edema when exposed to extreme environments (high-altitude or deep diving) or while performing strenuous exercises. Recent data support the hypothesis that these forms of acute pulmonary edema might be due to a limited number of stimuli, often overlapping each other, inducing pulmonary capillary stress failure. Pathophysiology of nontoxic pulmonary edema occurring in healthy people is still incompletely understood, but recent data suggest a role of three factors (hypoxia, increase in ambient pressure, and physical exercise) that, alone or in combination, may increase pulmonary capillary pressure up to a level overcoming the mechanical resistance of the blood-gas barrier.

Cardiovascular and respiratory effects of the neoprene wetsuit in non-immersed divers.

A neoprene wetsuit is widely used to reduce thermal dispersion during diving. Recent observations have pointed out that elastic recoil of the wetsuit might have significant compressive effects, able to affect water and electrolyte homeostasis during both dry and immersed conditions. The aim of this study was to evaluate the possible cardiovascular and respiratory effects of the neoprene wetsuit in dry conditions in a sample of experienced divers.

Undernutrition and Overnutrition Burden for Diseases in Developing Countries: The Role of Oxidative Stress Biomarkers to Assess Disease Risk and Interventional Strategies.

The increased life expectancy, urbanization, and unhealthy lifestyle characterized by a shift towards a sedentary lifestyle and decreased energy expenditure are considered the main drivers of epidemiological transition. In particular, developing countries are facing a double burden caused by coexisting under- and over-nutrition, which causes a change in the disease profile from infectious diseases to a chronic degenerative pattern. This review discusses the under- and over-nutrition context in Mauritania and India, two countries that are experiencing a nutritional transition, and where we began a collaboration with local medical staff to integrate interventional and diagnostic guidelines.

Mortality for chronic-degenerative diseases in Tuscany: Ecological study comparing neighboring areas with substantial differences in environmental pollution.

Objectives: Environmental pollution is associated with morbidity and mortality for chronic-degenerative diseases. Recent data points out a relationship between proximity to industrial plants and mortality due to neoplasms. The aim of this study has been to compare mortality due to chronic-degenerative diseases in the area of Tuscany (Bassa Val di Cecina), Italy, characterized by the presence of 2 neighboring municipalities similar in terms of size but with substantial differences in industrial activities: Rosignano (the site of chemical, energy production and waste processing industries) and Cecina (with no polluting activity).

A comparative evaluation of two decompression procedures for technical diving using inflammatory responses: compartmental versus ratio deco.

Introduction: The aim of this study was to compare two decompression procedures commonly adopted by technical divers: the ZH-L16 algorithm modified by 30/85 gradient factors (compartmental decompression model, CDM) versus the 'ratio decompression strategy' (RDS). The comparison was based on an analysis of changes in diver circulating inflammatory profiles caused by decompression from a single dive.

Methods: Fifty-one technical divers performed a single trimix dive to 50 metres' sea water (msw) for 25 minutes followed by enriched air (EAN50) and oxygen decompression.

Genetic predisposition to breath-hold diving-induced hemoptysis: Preliminary study.

Introduction: Breath-hold diving-induced hemoptysis (BH-DIH) has been reported in about 25% breath-hold divers (BHD) and is characterized by dyspnea, coughing, hemoptysis and chest pain. We investigated whether eNOS G894T, eNOS T786C and ACE insertion/deletion I/D genetic variants, are possible BH-DIH risk factors.

Methods: 108 experienced healthy instructor BHDs with the same minimum requirements (102 male, six female; mean age 43.

Delayed multifocal recurrent stress-induced cardiomyopathy after antidepressants withdrawal.

Stress-induced cardiomyopathy is an acute disease characterized by a large left ventricular apical dyskinesia ("apical ballooning"), triggered by intense emotional or physical stress, acute illnesses or, rarely, by alcohol or opiates withdrawal. Connection to stress and apical asynergy suggest a catecholamine-mediated pathogenesis. We recently observed a typical apical stress-induced cardiomyopathy, arising two weeks after a long-lasting antidepressant treatment withdrawal and recurring, a week later, with evidence of inferior wall akinesia.

Cardiac function and oxygen saturation during maximal breath-holding in air and during whole-body surface immersion.

Introduction: The magnitude of the oxygen-sparing effect induced by the diving response in humans is still under debate. We wished to compare cardiovascular changes during maximal breath-holding (BH) in air and during whole-body immersion at the surface in a group of BH divers.

Methods: Twenty-one divers performed a maximal static apnea in air or during whole-body immersion.

Cardiovascular changes during SCUBA diving: an underwater Doppler echocardiographic study.

Aim: Body immersion induces blood redistribution (from peripheral to intrathoracic vessels) and is a powerful autonomic stimulus (activating both parasympathetic and sympathetic systems). For these reasons, concerns have been raised about the safety of diving for subjects with previous heart disease. The aim of this study was to evaluate cardiovascular changes occurring during recreational SCUBA diving, as assessed by underwater Doppler echocardiography.

Increase of pulmonary arterial pressure in subjects with venous gas emboli after uncomplicated recreational SCUBA diving.

The presence of circulating gas bubbles has been repeatedly reported after uncomplicated SCUBA dives. The clinical and pathophysiological relevance of this phenomenon is still under debate but some experimental data suggest that silent bubbles may have a damaging potential on pulmonary endothelial cells. The aim of the present study was to evaluate the possible hemodynamic effect on pulmonary circulation of post-dive circulating gas bubbles.

Prevalence of acute respiratory symptoms in breath-hold divers.

Introduction: After repetitive deep dives, breath-hold divers are often affected by a syndrome characterized by typical symptoms such as cough, sensation of chest constriction, blood-striated expectorate (hemoptysis) and, rarely, an overt acute pulmonary edema syndrome, often together with various degrees of dyspnea. The aim of this work is an epidemiological investigation to evaluate the prevalence of acute respiratory symptoms (ARS) in breath-hold divers (BHDs) in practicing breath-hold diving.

Materials And Methods: A retrospective investigation has been performed using specific questionnaires completed by a selected sample of free-divers (212 breath-hold diving instructors--194 male, 18 female; mean age 34 +/- 6.

Post-dive ultrasound detection of gas in the liver of rats and scuba divers.

In a previous study, we obtained histologic documentation of liver gas embolism in the rat model of rapid decompression. The aim of the study was to assess in the same model occurrence and time course of liver embolism using 2-D ultrasound imaging, and to explore by this means putative liver gas embolism in recreational scuba divers. Following 42 min compression at 7 ATA breathing air and 12 min decompression, eight surviving female rats were anesthetized and the liver imaged by ultrasound at 20 min intervals up to 120 min.

Left ventricle changes early after breath-holding in deep water in elite apnea divers.

Purpose: To study by ultrasounds cardiac morphology and function early after breath-hold diving in deep water in elite athletes.

Methods: Fifteen healthy male divers (age 28 +/- 3 years) were studied using Doppler-echocardiography, immediately before (basal condition, BC) and two minutes after breath-hold diving (40 meters, acute post-apnea condition, APAC). Each subject performed a series of three consecutive breath-hold dives (20-30 and 40 m depth).