scholarly journals Bubbles in live-stranded dolphins

2011 ◽  
Vol 279 (1732) ◽  
pp. 1396-1404 ◽  
Author(s):  
S. Dennison ◽  
M. J. Moore ◽  
A. Fahlman ◽  
K. Moore ◽  
S. Sharp ◽  
...  
Keyword(s):  
Marine Mammals ◽  
Decompression Sickness ◽  
Bubble Formation ◽  
Post Mortem ◽  
Health Assessments ◽  
In The Wild ◽  
Beaked Whales ◽  
Clinically Significant ◽  
Probable Origin ◽  
Hepatic Portal

Bubbles in supersaturated tissues and blood occur in beaked whales stranded near sonar exercises, and post-mortem in dolphins bycaught at depth and then hauled to the surface. To evaluate live dolphins for bubbles, liver, kidneys, eyes and blubber–muscle interface of live-stranded and capture-release dolphins were scanned with B-mode ultrasound. Gas was identified in kidneys of 21 of 22 live-stranded dolphins and in the hepatic portal vasculature of 2 of 22. Nine then died or were euthanized and bubble presence corroborated by computer tomography and necropsy, 13 were released of which all but two did not re-strand. Bubbles were not detected in 20 live wild dolphins examined during health assessments in shallow water. Off-gassing of supersaturated blood and tissues was the most probable origin for the gas bubbles. In contrast to marine mammals repeatedly diving in the wild, stranded animals are unable to recompress by diving, and thus may retain bubbles. Since the majority of beached dolphins released did not re-strand it also suggests that minor bubble formation is tolerated and will not lead to clinically significant decompression sickness.

“Gas and Fat Embolic Syndrome” Involving a Mass Stranding of Beaked Whales (Family Ziphiidae) Exposed to Anthropogenic Sonar Signals

2005 ◽  
Vol 42 (4) ◽  
pp. 446-457 ◽  
Author(s):  
A. Fernández ◽  
J. F. Edwards ◽  
F. Rodríguez ◽  
A. Espinosa de los Monteros ◽  
P. Herráez ◽  
...  
Keyword(s):  
Canary Islands ◽  
Marine Mammals ◽  
Decompression Sickness ◽  
Bubble Formation ◽  
Fat Embolism ◽  
Diving Behavior ◽  
Associated Lesions ◽  
Beaked Whales ◽  
Mass Stranding

A study of the lesions of beaked whales (BWs) in a recent mass stranding in the Canary Islands following naval exercises provides a possible explanation of the relationship between anthropogenic, acoustic (sonar) activities and the stranding and death of marine mammals. Fourteen BWs were stranded in the Canary Islands close to the site of an international naval exercise (Neo-Tapon 2002) held on 24 September 2002. Strandings began about 4 hours after the onset of midfrequency sonar activity. Eight Cuvier's BWs (Ziphius cavirostris), one Blainville's BW (Mesoplodon densirostris), and one Gervais' BW (Mesoplodon europaeus) were examined postmortem and studied histopathologically. No inflammatory or neoplastic processes were noted, and no pathogens were identified. Macroscopically, whales had severe, diffuse congestion and hemorrhage, especially around the acoustic jaw fat, ears, brain, and kidneys. Gas bubble-associated lesions and fat embolism were observed in the vessels and parenchyma of vital organs. In vivo bubble formation associated with sonar exposure that may have been exacerbated by modified diving behavior caused nitrogen supersaturation above a threshold value normally tolerated by the tissues (as occurs in decompression sickness). Alternatively, the effect that sonar has on tissues that have been supersaturated with nitrogen gas could be such that it lowers the threshold for the expansion of in vivo bubble precursors (gas nuclei). Exclusively or in combination, these mechanisms may enhance and maintain bubble growth or initiate embolism. Severely injured whales died or became stranded and died due to cardiovascular collapse during beaching. The present study demonstrates a new pathologic entity in cetaceans. The syndrome is apparently induced by exposure to mid-frequency sonar signals and particularly affects deep, long-duration, repetitive-diving species like BWs.

scholarly journals Deadly diving? Physiological and behavioural management of decompression stress in diving mammals

2011 ◽  
Vol 279 (1731) ◽  
pp. 1041-1050 ◽  
Author(s):  
S. K. Hooker ◽  
A. Fahlman ◽  
M. J. Moore ◽  
N. Aguilar de Soto ◽  
Y. Bernaldo de Quirós ◽  
...  
Keyword(s):  
Marine Mammal ◽  
Marine Mammals ◽  
Multiple Stressors ◽  
Decompression Sickness ◽  
Tissue Injury ◽  
Bubble Formation ◽  
Gas Bubbles ◽  
Breath Hold ◽  
Technological Advances ◽  
Measured Time

Decompression sickness (DCS; ‘the bends’) is a disease associated with gas uptake at pressure. The basic pathology and cause are relatively well known to human divers. Breath-hold diving marine mammals were thought to be relatively immune to DCS owing to multiple anatomical, physiological and behavioural adaptations that reduce nitrogen gas (N 2 ) loading during dives. However, recent observations have shown that gas bubbles may form and tissue injury may occur in marine mammals under certain circumstances. Gas kinetic models based on measured time-depth profiles further suggest the potential occurrence of high blood and tissue N 2 tensions. We review evidence for gas-bubble incidence in marine mammal tissues and discuss the theory behind gas loading and bubble formation. We suggest that diving mammals vary their physiological responses according to multiple stressors, and that the perspective on marine mammal diving physiology should change from simply minimizing N 2 loading to management of the N 2 load . This suggests several avenues for further study, ranging from the effects of gas bubbles at molecular, cellular and organ function levels, to comparative studies relating the presence/absence of gas bubbles to diving behaviour. Technological advances in imaging and remote instrumentation are likely to advance this field in coming years.

Hyperbaric treatment of air or gas embolism: current recommendations

2019 ◽  
pp. 673-683
Author(s):  
Richard E. Moon ◽  
Keyword(s):  
Animal Studies ◽  
Decompression Sickness ◽  
Bubble Formation ◽  
Endothelial Damage ◽  
Neurological Deficits ◽  
Breath Hold ◽  
Gas Embolism ◽  
Hyperbaric Treatment ◽  
Pulmonary Capillaries ◽  
Venous Gas Embolism

Gas can enter arteries (arterial gas embolism, AGE) due to alveolar-capillary disruption (caused by pulmonary over-pressurization, e.g. breath-hold ascent by divers) or veins (venous gas embolism, VGE) as a result of tissue bubble formation due to decompression (diving, altitude exposure) or during certain surgical procedures where capillary hydrostatic pressure at the incision site is subatmospheric. Both AGE and VGE can be caused by iatrogenic gas injection. AGE usually produces stroke-like manifestations, such as impaired consciousness, confusion, seizures and focal neurological deficits. Small amounts of VGE are often tolerated due to filtration by pulmonary capillaries; however VGE can cause pulmonary edema, cardiac “vapor lock” and AGE due to transpulmonary passage or right-to-left shunt through a patient foramen ovale. Intravascular gas can cause arterial obstruction or endothelial damage and secondary vasospasm and capillary leak. Vascular gas is frequently not visible with radiographic imaging, which should not be used to exclude the diagnosis of AGE. Isolated VGE usually requires no treatment; AGE treatment is similar to decompression sickness (DCS), with first aid oxygen then hyperbaric oxygen. Although cerebral AGE (CAGE) often causes intracranial hypertension, animal studies have failed to demonstrate a benefit of induced hypocapnia. An evidence-based review of adjunctive therapies is presented.

scholarly journals Cetacean strandings along the Pacific and Caribbean coasts of Nicaragua from 2014 to 2021

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Joëlle De Weerdt ◽  
Eric Angel Ramos ◽  
Etienne Pouplard ◽  
Marc Kochzius ◽  
Phillip Clapham
Keyword(s):  
Marine Mammals ◽  
Sperm Whale ◽  
Distribution Patterns ◽  
Sperm Whales ◽  
The Pacific ◽  
Toothed Whale ◽  
Beaked Whales ◽  
Causes Of Mortality ◽  
Cuvier’S Beaked Whale ◽  
Stenella Attenuata

AbstractDocumenting marine mammal strandings provides important information needed to understand the occurrence and distribution patterns of species. Here, we report on strandings of cetaceans on the Pacific (n = 11) and Caribbean (n = 2) coasts of Nicaragua, documented opportunistically from 2014 to 2021. Strandings included three species of baleen whale (blue whale Balaenoptera musculus, Bryde’s whale Balaenoptera edeni, humpback whale Megaptera novaeangliae) and five species of toothed whale (dwarf sperm whale Kogia sima, Guiana dolphin Sotalia guianensis, pantropical spotted dolphin Stenella attenuata, spinner dolphin Stenella longirostris, Cuvier’s beaked whale Ziphius cavirostris). These are the first published accounts of blue whales, Bryde’s whales, dwarf sperm whales, and Cuvier’s beaked whales in Nicaraguan waters. Limited resources and the advanced decomposition of animals prevented necropsies in most cases, the identification of the causes of mortality in all cases, and the species identification of two dolphins. Information derived from these stranding events offers new insights into the occurrence of marine mammals on the Pacific and Caribbean coasts of Nicaragua and Central America.

Blood platelet-derived microparticles release and bubble formation after an open-sea air dive

2012 ◽  
Vol 37 (5) ◽  
pp. 888-892 ◽  
Author(s):  
Jean-Michel Pontier ◽  
Emmanuel Gempp ◽  
Mihaela Ignatescu
Keyword(s):  
Platelet Aggregation ◽  
Decompression Sickness ◽  
Blood Platelets ◽  
Water Immersion ◽  
Bubble Formation ◽  
Blood Platelet ◽  
Field Conditions ◽  
Control Group ◽  
Open Sea ◽  
Experimental Group

Bubble-induced platelet aggregation offers an index for evaluating decompression severity in humans and in a rat model of decompression sickness. Endothelial cells, blood platelets, or leukocytes shed microparticles (MP) upon activation and during cell apoptosis. The aim was to study blood platelet MP (PMP) release and bubble formation after a scuba-air dive in field conditions. Healthy, experienced divers were assigned to 1 experimental group (n = 10) with an open-sea air dive to 30 msw for 30 min and 1 control group (n = 5) during head-out water immersion for the same period. Bubble grades were monitored with a pulsed doppler according to Kissman Integrated Severity Score (KISS). Blood samples for platelet count (PC) and PMP (annexin V and CD41) were taken 1 h before and after exposure in both groups. The result showed a decrease in post-dive PC compared with pre-dive values in experimental group with no significant change in the control group. We observed a significant increase in PMP values after the dive while no change was revealed in the control group. There was a significant positive correlation between the PMP values after the dive and the KISS bubble score. The present study highlighted a relationship between the post-dive decrease in PC, platelet MP release, and bubble formation. Release of platelet MPs could reflect bubble-induced platelet aggregation and could play a key role in alteration of the coagulation. Further studies must investigate endothelial and leukocyte MP release in the same field conditions.

The protective effects of 1,3-butanediol acetoacetate diester on decompression sickness in rats

2021 ◽  
Author(s):  
Kun Zhang ◽  
Haidong Zhang ◽  
Hongjie Yi ◽  
Guoyang Huang ◽  
Xupeng Zhao ◽  
...  
Keyword(s):  
Inflammatory Responses ◽  
Decompression Sickness ◽  
Bubble Formation ◽  
Antioxidant Properties ◽  
Oxygen Toxicity ◽  
Causative Factor ◽  
Male Rats ◽  
Drug Candidate ◽  
Pharmacokinetic Analysis ◽  
Protective Effects

Inert gas bubbles are widely accepted as the causative factor of decompression sickness (DCS), resulting in gas embolism and systemic inflammatory responses. The anticonvulsive ketone ester 1,3-butanediol acetoacetate diester (BD-AcAc2) was reported to have the characteristics of increasing blood oxygen partial pressure and anti-inflammation, and was thought to have the potential to reduce bubble formation and alleviate the pathological process of DCS. This study aims to investigate the potential protection of BD-AcAc2 against DCS in a rat model. A single dose of BD-AcAc2 was administered orally to adult male rats (5 g/kg body weight), followed by pharmacokinetic analysis or simulated air dives. After decompression, signs of DCS were monitored, and blood was sampled for biochemical measurements. Blood ketosis peaked at 2 h and lasted for more than 4 h.The incidence of DCS was decreased and postponed significantly in rats treated with BD-AcAc2 compared with those treated with saline (P<0.05). Though BD-AcAc2 failed to reduce bubble load (P>0.05), it showed an obvious decreasing trend. BD-AcAc2 significantly increased blood ppO2 and ameliorated oxidative and inflammatory responses, representing by increased plasma MDA, IL-1, IL-6 and TNF-α and decreased glutathione thiol (P<0.05), while blood pH remained unchanged (P>0.05). These results suggest that BD-AcAc2 exerted beneficial effects on DCS rats mainly related to increasing ppO2, anti-inflammatory and antioxidant properties. Together with its capacity for delaying CNS oxygen toxicity seizures, BD-AcAc2 might be an ideal drug candidate for DCS prevention and treatment.

Different effect of l-NAME treatment on susceptibility to decompression sickness in male and female rats

2014 ◽  
Vol 39 (11) ◽  
pp. 1280-1285 ◽  
Author(s):  
Aleksandra Mazur ◽  
Peter Buzzacott ◽  
Kate Lambrechts ◽  
Qiong Wang ◽  
Marc Belhomme ◽  
...  
Keyword(s):  
Decompression Sickness ◽  
Tap Water ◽  
Bubble Formation ◽  
Female Rats ◽  
Control Group ◽  
No Production ◽  
Male And Female ◽  
Male And Female Rats ◽  
Expression Activity ◽  
No Bioavailability

Vascular bubble formation results from supersaturation during inadequate decompression contributes to endothelial injuries, which form the basis for the development of decompression sickness (DCS). Risk factors for DCS include increased age, weight–fat mass, decreased maximal oxygen uptake, chronic diseases, dehydration, and nitric oxide (NO) bioavailability. Production of NO is often affected by diving and its expression–activity varies between the genders. Little is known about the influence of sex on the risk of DCS. To study this relationship we used an animal model of Nω-nitro-l-arginine methyl ester (l-NAME) to induce decreased NO production. Male and female rats with diverse ages and weights were divided into 2 groups: treated with l-NAME (in tap water; 0.05 mg·mL–1 for 7 days) and a control group. To control the distribution of nitrogen among tissues, 2 different compression–decompression protocols were used. Results showed that l-NAME was significantly associated with increased DCS in female rats (p = 0.039) only. Weight was significant for both sexes (p = 0.01). The protocol with the highest estimated tissue pressures in the slower compartments was 2.6 times more likely to produce DCS than the protocol with the highest estimated tissue pressures in faster compartments. The outcome of this study had significantly different susceptibility to DCS after l-NAME treatment between the sexes, while l-NAME per se had no effect on the likelihood of DCS. The analysis also showed that for the appearance of DCS, the most significant factors were type of protocol and weight.

Human dose-response relationship for decompression and endogenous bubble formation

1990 ◽  
Vol 69 (3) ◽  
pp. 914-918 ◽  
Author(s):  
R. G. Eckenhoff ◽  
C. S. Olstad ◽  
G. Carrod
Keyword(s):  
Dose Response ◽  
Continuous Wave ◽  
Decompression Sickness ◽  
Bubble Formation ◽  
Nonlinear Least Squares ◽  
Response Relationship ◽  
Dose Response Relationship ◽  
Continuous Wave Doppler ◽  
Human Dose ◽  
The Hill

The dose-response relationship for decompression magnitude and venous gas emboli (VGE) formation in humans was examined. Pressure exposures of 138, 150, and 164 kPa (12, 16, and 20.5 ft of seawater gauge pressure) were conducted in an underwater habitat for 48 h. The 111 human male volunteer subjects then ascended directly to the surface in less than 5 min and were monitored for VGE with a continuous-wave Doppler ultrasound device over the precordium or the subclavian veins at regular intervals for a 24-h period. No signs or symptoms consistent with decompression sickness occurred. However, a large incidence of VGE detection was noted. These data were combined with those from our previously reported experiments at higher pressures, and the data were fit to a Hill dose-response equation with nonlinear least-squares or maximum likelihood routines. Highly significant fits of precordial VGE incidences were obtained with the Hill equation (saturation depth pressure at which there is a 50% probability of detectable VGE [D(VGE)50] = 150 +/- 1.2 kPa). Subclavian monitoring increased the sensitivity of VGE detection and resulted in a leftward shift [D(VGE)50 = 135 +/- 2 kPa] of the best-fit curve. We conclude that the reduction in pressure necessary to produce bubbles in humans is much less than was previously thought; 50% of humans can be expected to generate endogenous bubbles after decompression from a steady-state pressure exposure of only 135 kPa (11 ft of seawater). This may have significant implications for decompression schedule formulation and for altitude exposures that are currently considered benign. These results also imply that endogenous bubbles arise from preexisting gas collections.

scholarly journals Aquatic Biota is Not Exempt from Coronavirus Infections: An Overview

2020 ◽  
Author(s):  
Gabriel Núñez-Nogueira ◽  
Andres Arturo Granados-Berber
Keyword(s):  
Marine Mammals ◽  
Viral Infections ◽  
Aquatic Organisms ◽  
Marine Sponges ◽  
Animal Origin ◽  
Aquatic Biota ◽  
Bird Populations ◽  
Terrestrial Environments ◽  
In The Wild ◽  
Human Health Effects

Coronaviruses are pathogens recognized for having an animal origin, commonly associated with terrestrial environments. However, although in a few cases, there are reports of their presence in aquatic organisms like fish, frogs, waterfowls and marine mammals. None of these cases has led to human health effects when contact with these infected organisms has taken place, whether they are alive or dead. Aquatic birds seem to be the main group carrying and circulating these types of viruses among healthy bird populations. Although the route of infection for CoVID-19 by water or aquatic organisms has not yet been observed in the wild, the relevance of its study is highlighted because there are cases of other viral infections known to have been transferred to humans by aquatic biota. It is encouraging to know that aquatic species, such as fish, marine mammals, and amphibians, shows very few cases of coronaviruses and that some other aquatic animals may also be a possible source of cure or treatment against then, as some evidence with algae and marine sponges suggest.

scholarly journals Aquatic Biota is Not Exempt from Coronavirus Infections: An Overview

2020 ◽  
Author(s):  
GABRIEL NÚÑEZ-NOGUEIRA ◽  
Andres Arturo Granados-Berber
Keyword(s):  
Marine Mammals ◽  
Viral Infections ◽  
Aquatic Organisms ◽  
Marine Sponges ◽  
Animal Origin ◽  
Aquatic Biota ◽  
Bird Populations ◽  
Terrestrial Environments ◽  
In The Wild ◽  
Human Health Effects

Coronaviruses are pathogens recognized for having an animal origin and commonly associated with terrestrial environments. However, although in few cases, there are reports of their presence in aquatic organisms like fish, crustaceans, waterfowls and marine mammals. None of these cases have even led to human health effects, when contact with these infected organisms, whether they are alive or dead. Aquatic birds seem to be the main group in carrying and circulating these types of viruses in healthy bird populations and play an important role in these environments. Although the route of infection for CoVID-19 (Coronavirus disease 2019) by water or aquatic organisms, has not yet been observed in the wild, the relevance of its study is highlighted , because there are cases of other viral infections (no coronavirus), which are known to have been transferred to the human by aquatic biota. What is even better, it becomes encouraging to know that aquatic species shows very few cases in fishes, marine mammals, and crustaceans, and some other aquatic animals may also be a possible source of cure or treatment against coronaviruses, as some evidence with algae and marine sponges suggests.

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