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A Marroni

Publications and source records attributed to A Marroni.

At least 19 recordsLinked to original sources
PubMed2004

A deep stop during decompression from 82 fsw (25 m) significantly reduces bubbles and fast tissue gas tensions.

In spite of many modifications to decompression algorithms, the incidence of decompression sickness (DCS) in scuba divers has changed very little. The success of stage, compared to linear ascents, is well described yet theoretical changes in decompression ratios have diminished the importance of fast tissue gas tensions as critical for bubble generation. The most serious signs and symptoms of DCS involve the spinal cord, with a tissue half time of only 12.5 minutes. It is proposed that present decompression schedules do not permit sufficient gas elimination from such fast tissues, resulting in bubble formation. Further, it is hypothesized that introduction of a deep stop will significantly reduce fast tissue bubble formation and neurological DCS risk. A total of 181 dives were made to 82 fsw (25 m) by 22 volunteers. Two dives of 25 min and 20 min were made, with a 3 hr 30 min surface interval and according to 8 different ascent protocols. Ascent rates of 10, 33 or 60 fsw/min (3, 10, 18 m/min) were combined with no stops or a shallow stop at 20 fsw (6 m) or a deep stop at 50 fsw (15 m) and a shallow at 20 fsw (6 m). The highest bubbles scores (8.78/9.97), using the Spencer Scale (SS) and Extended Spencer Scale (ESS) respectively, were with the slowest ascent rate. This also showed the highest 5 min and 10 min tissue loads of 48% and 75%. The lowest bubble scores (1.79/2.50) were with an ascent rate of 33 fsw (10 m/min) and stops for 5 min at 50 fsw (15 m) and 20 fsw (6 m). This also showed the lowest 5 and 10 min tissue loads at 25% and 52% respectively. Thus, introduction of a deep stop significantly reduced Doppler detected bubbles together with tissue gas tensions in the 5 and 10 min tissues, which has implications for reducing the incidence of neurological DCS in divers.

Atmospheric Pressure↗
PubMed1998

Intrathoracic pressure changes after Valsalva strain and other maneuvers: implications for divers with patent foramen ovale.

Scuba divers with patent foramen ovale (PFO) may be at risk for paradoxical nitrogen gas emboli when performing maneuvers that cause a rebound blood loading to the right atrium. We measured the rise and fall in intrathoracic pressure (ITP) during various maneuvers in 15 divers. The tests were standard isometric exercises (control), forceful coughing, knee bend (with and without respiration blocked), and Valsalva maneuver (maximal, gradually increased to reach control ITP, and as performed by divers to equalize middle ear pressure). All the maneuvers, as well as the downward slope of ITP at the release phase, were related to the control value. ITP levels were significantly higher than the standard isometric effort during a breath-hold knee bend (172%, P < 0.001), cough (133%, P < 0.05), and maximal Valsalva (136%, P < 0.05) whereas "usual" Valsalva maneuvers produced ITPs significantly lower than the standard (28%, P < 0.001). The downward slope of the pressure release curve was not significantly different among the different maneuvers (P < 0.1447). We conclude that maneuvers other than the usual divers' Valsalva are more likely to cause post-release central blood shift, both by the levels of ITP reached and by the time during which these ITPs are sustained. Divers (especially with PFO) should be advised to refrain from strenuous leg, arm, or abdominal exercise after decompression dives.

Adult↗
PubMed1983

[Bacteriological and clinical notes on otitis externa in saturation. Double-blind study on the efficacy of prophylactic and therapeutic preparations].

Microbiological analysis of the variation in the bacterial flora of the external auditory canal was carried out during 39 immersion in saturated solutions. A double blind test on the usefulness of prophylactic and therapeutic preparations was also carried out. Prophylactics. - 5% Al acetate in H2O (P1), Boric alcohol (P2), lactic acid in H2O (P3, Domeboro (P4), no prophylactic (P0). After the immersions, a significant increase in Pseudomonas Aeruginosa and Candida Albicans (p less than 0,01) was noted in the auricular bacterial flora. Gram positive bacteria in general were considerably reduced (p less than 0,01). Gram negative bacteria other than pseudomonas. A (p less than 0,3) and coagulase negative straphylococci (p less than 0,03) did not vary significantly. Prophylactic preparations P1 and P2 were shown to be significantly more effective than P3, P4 and P0 in preventing the symptomatology (p less than 0,01). The most effective therapeutic preparation was found to be a locally applied gentamycinpolymixin association.

Adult↗
PubMed1983

[Evaluations of 169 cases of decompression sickness treated in Italian hyperbaric centers 1980-1981].

An assessment was made of 169 cases of decompression sickness occurring during the period 1980-81. Nearly all (95,6%) were attributable to superficial planning and execution of the immersion and reascent to the surface marker as the result of panic. Breakdown in the diving apparatus was only responsible in 4.4% of cases. Irrispective of the intermediate decompression stages, the rate of reascent was more than 10 metres a minute in 71.6% of cases. Full recovery as a result of hyperbaric management was obtained in 78,2% type I sickness and 61.9% type II, with improvements in 17.3% and 35.1% respectively. The interval between emersion and treatment ranged from 1 to 72 hr, though the results of treatment were not significantly related to the rapidity of intervention (p greater than 0.05). Good results were dependent on the type of treatment employed, with a significantly better outcome (p less than 0.01) from U.S. Navy tables 2-2A, 3-3A, 4, 5 and 6 and the 2 + 6 recompression protocol, than from tables 5A and 6A.

Decompression Sickness↗
PubMed1983

[Physiopathologic changes and morbidity in divers in saturation. Epidemiologic evaluation of 9 years' activities (1973-1982)].

An epidemiological study was made of 315 man-saturations over a period of 4508 days worked in saturation. The results were compared with those from 541 drillers working on a high-isolation site for periods of 30 days per shift making a total of 16,230 working days. Saturation was asymptomatic in 15,9%. The average length of conditions not interfering with diving or work was 3 days in the sample and 4 days in the controls. There were only two instances of type I decompression sickness in the divers (0,6%). These were both resolved without complications. Two subjects had to give up for health reasons (one case of parotitis and one anxiety-depression syndrome). It is felt that saturation is a very safe procedure as far as immediate pathological consequences are concerned, and that its minor pathological forms are of a significantly different type from those of the control series, especially with regard to ORL forms, upper airway conditions, sleep disturbances, and sensations of malaise and poor adaptation.

Anxiety Disorders↗
PubMed1983

[Changes in the health status in occupational under-water activities].

For the past 10 years of so, Italian professional divers have had obligatory medical check-ups once a year. These check-ups are based on International standards and are particularly important for divers going to work abroad or in the open sea. The present report is based on clinical data about 100 professional divers aged 20-50. The subjects had worked 1-30 years accumulating a total of 200-5000 shallow dives. 41% had also done deep work using intervention and saturation techniques. No significant incidence of common was encountered. Radiology revealed bone alterations in 52 subjects (to the joints in 17 cases). Hearing problems were encountered in 47 divers, mostly slight and often totally or partially cured during the observation period. 5 subjects were found to be unsuitable for saturation work. The aetiopathogenetic significance of the alterations encountered is discussed in terms of the type and duration of diving practised.

Adult↗