Saturday, June 5, 2010

UW-Madison vs the Sheep

The University of Wisconsin’s official statement regarding the possibility that criminal charges may result from Dane County Circuit Court Judge Amy Smith's decision that there is probable cause to believe that university researchers violated one of the state’s crimes against animals statutes is included at the bottom of this entry.

Like so many of their claims regarding their use of animals, much of what they say about the decompression of the sheep has a ring of self-defense, of fabrication, of something other than the truth. Even more contrived and creatively deceptive are the statements and coverage of this situation in the ersatz state newspaper, the Wisconsin State Journal. I’ll write about that fanciful coverage in a separate post.

Lets consider the university’s official defense of its more than two decades of these excruciatingly painful experiments: “Findings from the study are already in use by the Navy and have been applied to mitigate decompression sickness in submariners and divers.”

Findings from the study [the study?] are already in use by the Navy. I wonder which findings those are?

The use of sheep in decompression experiments has a long thin history at the university. The most recent paper stemming from this line of research is:

Oxygen pre-breathing decreases dysbaric diseases in UW sheep undergoing hyperbaric exposure. Sobakin AS, Wilson MA, Lehner CE, Dueland RT, Gendron-Fitzpatrick AP. Undersea Hyperb Med. 2008.

But oxygen pre-breathing as a means to mitigate or prevent decompression sickness isn’t a new idea, so this can’t be one of the findings being used by the Navy. The Navy undoubtedly is well informed on the use of oxygen prebreathing and may use it, but not because of research conducted at the University of Wisconsin.

See for example: The effect of extended O2 prebreathing on altitude decompression sickness and venous gas bubbles. Waligora JM, Horrigan DJ Jr, Conkin J. Aviat Space Environ Med. 1987. This research was conducted at the Space Biomedical Research Institute, NASA/Johnson Space Center in Houston, Texas, using human subjects. The authors write:
The purpose of this study was to determine the effect of extended O2 prebreathing on symptom and bubble incidence during decompressions simulating extravehicular activity. The 38 subjects breathed O2 for a 6-h period prior to decompression to 4.3 psi. The subjects performed upper body exercise for 6 h. Subjects were monitored with a Doppler bubble detector and were encouraged to report all symptoms. Eight subjects were exposed to the same protocol after an 8-h prebreathe. Venous bubbles were detected in 18 of 38 subjects decompressed after the 6-h prebreathe. Four of these subjects reported symptoms of altitude decompression sickness. No symptoms or bubbles were detected in the eight subjects who had prebreathed 8 h.
In fact, researchers James T. Webb and Andrew A. Pilmanus at Brooks Air Force Base cite much earlier work on pure oxygen prebreathing as a means to reduce the occurrence of decompression sickness: Marbarger JP, Kadetz W, Variakojis D, Hansen J. The occurence of decompression sickness following denitrogenation at ground level and altitude. J. Aviat. Med. 1957.

If the university claims that their experiments on sheep have led the Navy to use oxygen prebreathing as a method of controlling decompression sickness, they are either ignorant of the facts, or else are lying. But maybe oxygen prebreathing isn’t what the university’s official statement is referring to.

In the papers below (apparently the complete result of this line of research at the University of Wisconsin-Madison), there does not seem to be even one conclusion or “discovery” that the Navy might or even could be using to “mitigate decompression sickness in submariners and divers.” It strongly appears that the only thing mentioned in the papers on decompression sickness published by researchers at the university involving sheep that the Navy might be using “to mitigate decompression sickness in submariners and divers” is oxygen prebreathing.

There seems to be a decade gap in published research on decompression at the university. The second most recent paper is:

Predicting risk of decompression sickness in humans from outcomes in sheep. Ball R, Lehner CE, Parker EC. J Appl Physiol. 1999:
We conclude that the sheep and human data sets are combinable under the scalable LE model with jointly estimated kinetic parameters and PXO. Predicting human responses from sheep only requires adjustment of the response parameters. Although it is tempting to place physiological interpretations on the parameters, they are best viewed as mathematical constructs that are quasiphysiological. We present an application of the model for predicting DCS risk on a dive not included in the calibration database that suggests the practical utility of this approach. Limitations of this study and directions for future research, including a direct test of the allometric scaling hypothesis, are discussed.
This isn’t helpful to Navy divers or submariners. It’s simply a (false and goofy) claim that human and sheep physiological data can be combined in a manner that will be more helpful for predicting the risk of decompression sickness in humans than human physiological data alone.

The next most recent paper is:

Dysbaric osteonecrosis in divers and caisson workers. An animal model. Lehner CE, Adams WM, Dubielzig RR, Palta M, Lanphier EH. Clin Orthop Relat Res. 1997:
Dysbaric osteonecrosis was induced successfully in adult sheep after 12 to 13, 24-hour exposures to compressed air (2.6-2.9 atmospheres absolute) during a 2-month period. All exposed sheep had decompression sickness and extensive bone and marrow necrosis in their long bones.... An animal model that can be used to investigate the pathogenesis, diagnosis, and treatment of dysbaric osteonecrosis is discussed.
But here, they say simply that they think sheep can be predictive models of dysbaric osteonecrosis in humans. Dysbaric osteonecrosis is the death of bone tissue caused by the expansion of dissolved nitrogen during rapid decompression.

The earlier papers don’t suggest any other possibilities either.

Experimental respiratory decompression sickness in sheep. Atkins CE, Lehner CE, Beck KA, Dubielzig RR, Nordheim EV, Lanphier EH. J Appl Physiol. 1988.

Lack of harmful effects from simulated dives in pregnant sheep. Bolton-Klug ME, Lehner CE, Lanphier EH, Rankin JH. Am J Obstet Gynecol. 1983.

Responses of fetal sheep to simulated no-decompression dives. Stock MK, Lanphier EH, Anderson DF, Anderson LC, Phernetton TM, Rankin JH. J Appl Physiol. 1980. (I don’t know where this research was performed. E.H. Lanphier was an author of the three studies above.)

The real reason the university is so miffed at having to obey the state’s laws is money. Their posturing and tears are staged and have no more connection to reality than Hamlet’s father’s ghost. Here’s the real concern:
Neurological Decompression Injury: Is Deep Stop Decompression Protective?
Principal Investigator: Marlowe Eldridge M.D.
Agency: DOD Navy
Status: Pending 10/01/2008-09/31/2011 (~$1,300,000)

This major goal of these studies is to improve our understanding of neurological decompression sickness and help evaluate deep stop use as a protective decompression strategy. We will use our established sheep model of the diver to determine the effects of various decompression scenarios with and without a deep stop on neurological decompression sickness. A variety of MR imaging techniques, will be used evaluate for subtle neurological injury and more importantly to gain insight into the mechanisms that may contribute to decompression neuronal injury.
Oddly, Dr. Eldridge seems not to have published a single paper stemming from his use of his “established sheep model of the diver.” His publication list is available on his website.

His name does show up on one abstract regarding decompression sickness presented at the Undersea & Hyperbaric Medical Society 2008 Annual Scientific Meeting in Salt Lake City, Utah. This was also just about the time that his $1.3 million grant seems to have kicked in.

Wisconsin’s law is unambiguous; in its entirety:
Decompression prohibited
No person may kill an animal by means of decompression.
This statute went into effect in 1985; the earliest work cited above was not then illegal.

University administration's statement regarding Circuit Court ruling on submarine rescue studies

June 3, 2010

The university is reviewing Dane County Circuit Court Judge Amy Smith's decision to defer animal cruelty charges involving longstanding submarine rescue studies to a special prosecutor.

These studies, using sheep and funded by the Navy, are designed to identify the best ways to prevent or treat decompression sickness that often occurs during a submarine rescue attempt.

The judge’s determination, although permitting the filing of charges, does not mean that any university employees have committed criminal conduct or even that they will be charged. The issue is before the court as a result of a petition by the Alliance for Animals and the People for the Ethical Treatment of Animals (PETA) subsequent to a decision by Dane County District Attorney Brian Blanchard, who concluded that pursuing charges would be an unwise use of limited resources.

Sheep have been used in these experiments because they share physiological characteristics with people that are highly relevant to decompression-associated diseases.

The studies in question were stopped when the university received an interpretation that they might contravene a state law intended to bar decompression as a form of euthanasia. Findings from the study are already in use by the Navy and have been applied to mitigate decompression sickness in submariners and divers.

See too:

Silly Secrecy
Is Brian Blanchard a Racist or Just Under Bucky's Spell?
The Sheep. Spin, spin, spin.
Standing Above the Law
The decompression of the sheep
UW Violating State Law and PHS Regs?

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