RESEARCH
_I
Study finds stresslowers productionof adult brain cells
other aforePutting a Price on
Stress is known to contribute to heart dis-ease, cancer and accidents. Now scientistshave found that stress markedly lowers brain-
cell production in adulthood.A new study confirms that a
specific brain area can grownew cells in an adult. But italso shows that stress can putthe brakes on.
"Stressful experiences decrease the gene-sis of neurons in a brain area of the adult treeshrew," said Elizabeth Gould of PrincetonUniversity. Her study appears in the Aprilissue of the Journal of Neuroscience.
Stress expert Robert Sapolsky of StanfordUniversity said the study is the first todemonstrate that stress can disrupt neuronproduction in the adult brain.
The idea that the adult brain of complexmammals can produce neurons is new initself. But recent research found that the den-tate gyrus area of the brain can produce newneurons in adult rats.
Gould's research shows this is also thecase in the adult tree shrew, a mammal moresimilar to humans than rodents. She said thefinding suggests that the neuron productionalso might occur in primates, includinghumans.
. Ultrasound now used to inspectplastic-sealed food containers
Ultrasound's ability to see where humaneyes cannot is being fine-tuned to improvefood inspection and make plastic-sealed food
containers safer and potentiallylonger-lasting.
Tests at the University of Illi-nois with a newly developedpulse-echo acoustic techniquehave spotted defects in seals
of less than 10 microns, which is one-fifth thediameter of a human hair. A new target is 6.5microns. Research findings were published inthe March issue of the Journal of Food Pro-tection.
How much can the ultrasound see?"We can distinguish what's in the channel
of a defect — if it's air, if it's water or if it'stiny strands of protein," said Scott A. Morris,a professor of food science and agricultural
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The Earth's free services are worth trillions of dollars, but environmental scientists warn that humansare depleting and undermining those resources at an alarming rate — and losing them will be costly
The value of natureMaintaining the health of nature's services
makes good economic sense, says Janet N.
OregonianIL
2M
& HEALTH
By RICHARD L HILLof The Oregonian staff
I firmly believe that theloss of nature's services
rai cPri nrnhhamc have dnminahari r .1
it pollution. Water pollution.Imperiled wildlife. Those human-
SECTIONFWEDNESDAY,
APRIL 16, 1997
E LINE.5555 i t _
mments on Science stories, call The7ide Line, a free service inside theI, at 225-5555 and enter this four-'93.
By KATY MULDOONof The Oregonian staff
The tides were on their side.For the first time, northern elephant seal
pups born this winter on Shell Island, southof Coos Bay, probably lived long enough tosurvive at sea.
By last week, six of the seven had left therocky outcrop where they were born, just offCape Arago.
It is the first time since the blubberymarine mammals established a breedingcolony there in 1993 that pups have survivedthe critical first 100 to 110 days of life. Inprevious winters, high tides and stormscoincided to sweep the young off the narrowbeach and out to sea before they were oldenough to survive.
But this winter was as mellow as a slacktide.
Scientists from the Oregon Institute ofMarine Biology in Charleston kept a sharpeye on the whiskered pups. With help fromthe Oregon Department of Fish and Wildlife,the scientists tagged six pups – three maleand three female. They didn't spot the sev-
enth pup until later, so they didn't tag it ordetermine its gender.
The tags will help marine biologists learnmore about the elephant seals' range andhabits.
Theirs is a well-studied species — onethat has rebounded remarkably from thebrink of hunter-caused extinction. In the late1800s, just 50 to 100 northern elephantseals were thought to be left; they lived in asingle colony on an island off the coast ofBaja California. Today, about 160,000 ani-mals range along the Pacific coast, breedingmostly on islands and beaches of Southernand Central California. Shell Island, part ofthe Oregon Islands National Wildlife Refuge,is home to the most northerly breedingcolony.
Oregon's pups were born in January. Themothers nurse their pups for about a month,then abruptly abandon them and head tosea. But the milk they've provided is 55 per-cent fat, a diet rich enough to sustain theyoung seals for 10 weeks or so.
A fun fact: Some pups nurse from two orthree females and grow to 600 pounds;they're called "superweaners."
Elephant seals are awkward beasts – theylook like slug s on steroids – and the pupsappear somewhat afraid of the water at first.But in late March or April, off they go insearch of new territory and the first mealthey've had in months.
"We don't know what their fate is," saidJan Hodder, "and we won't know until thefirst possible time they will return to land
STEVEN A NEHUThe Oregonian
Northern elephant seal pups born onthe southern Oregon coast have sur-vived and headed out to sea.
this fall."Hodder is an associate professor and edu-
cation coordinator at Oregon Institute ofMarine Biology. She has tracked the ShellIsland elephant seals and wrote an articleabout them to be published this fall in thejournal Marine Mammal Science.
It is thought many of the seals feed onsquid, skates and small sharks off the coastof Washington and British Columbia; killerwhales and sharks prey upon them.
Hodder said that at Arlo Nuevo StateReserve, a major elephant seal gatheringarea 55 miles south of San Francisco, one-fourth to one-half of the tagged pups are
never seen again. So she is unsure whethershe'll ever get another look at the ShellIsland pups, though they are inclined toreturn to the site where they were born.
Elephant seals come ashore several timesa year to molt, rest, breed and give birth.
During the next month, females and 1- to3-year-old elephant seals will haul out atCape Arago and other beaches throughoutOregon to molt, a process in which they losefur and skin. They don't eat or drink duringthe approximately three weeks on land, Hod-der said. Sub-adult males and adult maleswill follow suit through August.
The pups born this year will haul out in thefall to rest for a few weeks, but they won'tmolt until next spring.
Elephant seals get their names from themales, whose long snouts resemble ele-phant trunks.
To learn more, check out the Internet siteput together by elephant seal experts at ArloNuevo. The address is http://www.anonue-vo.org
COMING UP■ Look for these graphics to run monthly in the
Science section:1st Wednesday: astronomy2nd Wednesday: weather3rd Wednesday: animals4th Wednesday: geology5th Wednesday: environment
Earns free services are worth trillions of dollars, but environmental scientists warn that humansare depleting and undermining those resources at an alarming rate — and losing them will be costly
pulse-echo acoustic technique""s1 have spotted defects in seals
of less than 10 microns, which is one-fifth thediameter of a human hair. A new target is 6.5microns. Research findings were published inthe March issue of the Journal of Food Pro-tection.
How much can the ultrasound see?"We can distinguish what's in the channel
of a defect — if it's air, if it's water or if it'stiny strands of protein," said Scott A. Morris,a professor of food science and agriculturalengineering. "We can tell if a hole is empty orfull. We can look at other contaminants, suchas grease or dust, that may be in the seal andaffect its strength."
Hubble Space Telescope picks upmysterious burst of gamma rays
The Hubble Space Telescope has shed a lit-tle light on one of the most mysterious eventsin the universe.
Gamma rays make up the uppermostreaches of the electromagneticspectrum, more energeticeven than X-rays. About oncea day, like lightning, a flash ofgamma rays appears some-where in the cosmos. For two
decades, scientists have wondered wherethese bursts come from and how they areproduced.
Efforts to find a source of such gammarays had failed. But in February, scientistsannounced that two ground-based telescopeshad picked up something visible — an "opti-cal counterpart" — associated with a gammaray burst. The observatories took two imagesa week apart and detected a clearly visible iffading object.
In March, the Hubble telescope scanned inthe direction of the object after it had dimmedfrom the view of surface telescopes and start-ed tracking the remnants of light.
Scientists don't know what the object is,and they don't think it's the only source ofgamma ray bursts. But the new Hubbleobservations might help them find outwhether the rays are coming from within theMilky Way or from a distant galaxy.
Nose-drop vaccine for influenzasucceeds in human tests in Israel
The effectiveness of an innovative anti-i nfluenza vaccine developed at the HebrewJniversity-Hadassah Medical School inJerusalem has been demonstrated oniumans in clinical tests.
The vaccine is administeredas nose drops, not as an injec-tion. Delivering the vaccinethrough the nose provides afirst line of defense against theflu virus, which enters the
iy via the respiratory system. The nasal;Me stimulates the creation of antibodies'e respiratory system and in the blood,enting the flu virus from gaining as old in the body.
vaccine was tested this winter on 51its at the medical school. None of theis became ill with the flu.
— Compiled by Richard L. Hill
By RICHARD L. HILLof The Oregonian staff
it pollution. Water pollution.Imperiled wildlife. Those human-caused problems have dominatedthe environmental spotlight sincethe first Earth Day in 1970.
But a new concern is emerging among scien-tists: Nature's free services to humans are introuble. With the planet-awareness day beingobserved again Tuesday, ecologists are draw-ing attention to the topic, which they say hasbeen largely ignored by the public and policy-makers.
Environmental scientists warn thatalthough natural ecosystems provide servicesworth trillions of dollars — at least $30 trillionby one rough estimate — they're being deplet-ed and undermined by human activities.
Those human life-support systems includepollination of crops, pest control, flood control,purification of air and water, soil fertility andregulation of climate. Losing those free ser-vices will be costly, scientists say.
"As more and more of the surface of theEarth is modified by human activities, we arelosing more and more of these services," saidJane Lubchenco, a zoology professor at OregonState University. "These services until nowhave been taken for granted."
Lubchenco organized a symposium on the
INN —
I firmly believe that theloss of nature's servicesis one of the mostcrucial issues facinghumanity today — farand beyond anything you will hear onthe Sunday talk shows.
Paul R. Ehrlich,professor of biology at Stanford University
on the value of nature's services
99
subject at the recent annual meeting in Seattleof the American Association for the Advance-ment of Science. "We don't buy and sell the ser-vices ecosystems provide, but we do buy andsell their goods," said Lubchenco, who servesas association board chairman. "There's animmediate short-term benefit to a lot of humanactivities — filling in a wetland to put in ashopping mall, cutting down a forest to get theresources for timber. So you get some econom-ic benefit, but the cost-accounting does not
Please turn toEARTH DAY, Page F2
The value of natureMaintaining the health of nature's services
makes good economic sense, says Janet N.Abramovitz, a senior researcher with the World-watch Institute. Here are a few of the examples shegives in the institute's "State of the World 1997":
Some wetlands near cities have measured val-ues of $40,000 a hectare (nearly 2'/z acres). Despitetheir value, the United States and Europe have lostmore than half of their wetlands. Asia has lost 27percent.
Restoration of half of the upper Mississippi'slost wetlands could control a flood of the magnitudeof the 1993 disaster, which cost about $15 billion. Thisrestoration would affect 3 percent of the region's landbut would prevent a repeat of the disaster.
■ In the United States, 70 percent to 95 percent offisheries worth more than $3 billion at docksidedepend on threatened coastal wetlands and estuar-ies.
About 80 percent of the world's crops and one-third of U.S. agricultural output depend on pollina-tors such as bees, insects, bats and birds, whose pop-ulations are in jeopardy.
The pollination services of bees are worth asmuch as 100 times more than their honey.
Crop improvements such as disease resistanceand improved yields come from breeding with wildrelatives. Nature's crop genetic library has addedan estimated $66 billion to the global economy.
The value of coastal mangrove ecosystems forflood control has been estimated at $300,000 a kilo-meter in Malaysia. The figure represents the cost ofbuilding rock walls to replace that service.
NORTHAMERICA
SOUTHAMERICAE Si Cleared
61mA forestland
■ Frontiermm forest
today
1 Current non-frontier
forest
Report card showsgains and lossesScores of experts from around the worldworked to produce this map, said to be thefirst of its kind, showing how the Earth's forestshave changed, in rough outline, in the past 8,000years. Originally, all shaded areas were ecologicallyintact "frontier forests," according to the study by the WorResources Institute, a Washington-based research organization.Darkest areas represent frontier forests remaining today. Areaswith lightest shading represent forests disturbed by logging,fragmentation and other human activities. Medium shadingindicates forests that have been cleared.
Source: World Resources Institute
WOR RESTS ■
Savines would limit scientists
Big changes loomfor U.S. activitiesaround South Pole■ The need to spend money on desk work and computer analyses.facilities probably will crimp
to Antarctic territory. These claimsare held in indefinite abeyance bythe treaty, but they have never beenrelinquished.
U.S. stations are by far the mostpopulous on the continent, and U.S.influence is regarded as an impor-tant factor in keeping the peace.
Every dollar the National ScienceFoundation can save for rebuildingSouth Pole Station will be needed.Even if large savings are realized,the foundation might have to closePalmer Station for several Antarc-
F2 II 2M SCIENCE THE OREGONIAN, WEDNESDAY, AP RIL 16, 1997
Earth Day: Nature's ervices are being lost throughout the world■ Continued from Page Flinclude the loss of these ecosystemservices."
Lubchenco and more than 30other scientists also have con-tributed to a new book, "Nature'sServices," which is the first to detailhumanity's dependence on thesenatural systems.
Gretchen C. Daily, an ecologist atStanford University who edited thebook, said most of nature's goods —such as timber, pharmaceuticals,seafood, fuel wood and animal fod-der — are well-recognized. But thepublic is generally unaware of thenature and value of the services.
"For example, few people knowthat one in three mouthfuls of ourfood was derived from plants thatwere pollinated by natural pollina-tors living in natural ecosystemsnext to farmland," Daily said. Andabout 44 billion metric tons of wasteis processed annually by naturalecosystems, she said.
Paul R. Ehrlich, a professor obiology at Stanford University, saidif people don't become aware now ofthe value of nature's services,they're going to learn about them inoften catastrophic ways. He citedthe overharvesting of forests aspartly responsible for this winter'slethal and damaging mudslides inOregon and Washington.
Ehrlich said a recent study by`'Julia A. Jones of Oregon State Uni-versity and Gordon E. Grant of theU.S. Forest Service found clear-cut-ting forests and building roadsincreased peak flows in mountainstreams by as much as 50 percent.He said the destruction of the natur-al flood and mudslide controls pro-vided by forests should be includedin the cost of timber harvesting onpublic lands.
"But these kinds of things arehappening throughout the world,"Ehrlich said. "There's everythingfrom rising fish prices to the loss of24 billion tons of topsoil each year.
Interference with nature's servicescomes home to the rich in higherfish prices and loss of sports fish-eries; loss of real-estate values; high-er risks from 'natural disasters'such as floods, droughts and otherweather events."
Ehrlich added that when ecosys-tems are disrupted, North Ameri-cans suffer outbreaks of agricultur-al pests; acidification and decline offorests; and rapid siltation of reser-voirs, threatening the sustainabilityof irrigation and power generation.
"I firmly believe that the loss ofnature's services is one of the mostcrucial issues facing humanitytoday — far and beyond anythingyou will hear on the Sunday talkshows," he said.
New York City recently discov-ered what it costs to gradually losethe natural regulation and purifica-tion of water by soils and vegeta-tion. The city receives 90 percent ofits drinking water from reservoirsin the Catskill Mountains. The
reservoirs, which supply water toabout 9 million people, are fed byrivers and streams. But increasingpollution from a variety of sources— from weekend homes and theirseptic fields to runoff from farm fer-tilizer and livestock wastes — hasled to a deterioration in the water'squality, making it a potential healththreat.
City officials were faced withbuilding the world's largest water-filtration plant, a $4 billion projectthat would filter more than a billiongallons of water a day from thereservoirs. But three months ago,the city chose to spend $600 millionin a five-year program to restorewater quality.
The project includes buying thou-sands of acres of land around thereservoirs to improve and preservethe watershed.
Geoffrey Heal, an economist atColumbia University who has beenstudying ways of placing dollar val-ues on ecosystem services, said New
York City's dilemma will be com-mon elsewhere in coming years. Hesaid the cost for replacing the plan-et's natural water-control andwater-purification systems would beabout $900 billion.
"I think it's a reasonable forecastthat by the year 2020, the invest-ment required for the infrastructureto supply drinkable water will be ona scale comparable to the invest-ment we now have in providingpower," Heal said. "I'd also be will-ing to bet that by 2020 — in signifi-cant parts of the world — puredrinking water will be at least halfthe price of crude oil — it will be aexpensive and valuable."
Heal said researchers at the Uni-versity of Maryland and CornellUniversity had made a rough esti-mate of $30 trillion for the costs ofall global ecosystem services. Hebelieves that's a conservative fig-ure.
Ehrlich, in an interview last weekin Portland, called the notion that
environmental and economic con-cerns don't mesh "ridiculous."
"Our economy depends entirelyon the proper function of a wholearray of environmental systems,"he said. "Without them, you're notgoing to have any economy at all."
Janet N. Abramovitz, a seniorresearcher with the WorldwatchInstitute, agrees. "In just a few cen-turies we have gone from living offnature's interest to depleting thenatural capital that has accumulat-ed over millions of years in evolu-tion," she wrote in the institute's"State of the World 1997."
"As a result, governments, busi-nesses -- and ultimately, taxpayers
must pay for the services thatnature can no longer provide."
Richard L. Hill covers science forThe Oregonian's Health/ Medicine/Science team. He can be reached at221-8238 or by fax at 294- 4150.
New York Times News Service
D 1\
Try thesebooks formore detailedinformationabout the nat-ural servicesthat ecosys-tems providesociety:"Nature's Ser-vices: Societal Dependence onNatural Ecosystems," edited byGretchen C. Daily (Island Press;$49.95 hard cover, $24.95paperback)"The Work of Nature: How theDiversity of Life Sustains Us," byYvonne Baskin (Island Press;$25)"State of the World 1997," annu-al report by Worldwatch Insti-tute; Chapter 7, "ValuingNature's Services," by Janet N.Abramovitz (W.W. Norton;$13.95)
'MEW ‘111.111.•
for U.S. activitiesaround South Pole
MALCOLM W. BROWNE/New York Times News Service
Researchers enter the snow-walled entrance to the National Science Foundation dome at South Pole Station,which the foundation wants to dismantle and send back to the United States because of safety and opera-tional hazards.
Schematic drawing of the proposed replacement for the decaying dome at SouthPole Station. Expected to cost about $120 million, the pair of residential and officeunits would rest on stilts, above drifting snow.
Modules
Centraltower
Source: NationalScience Foundation
New York Times News Service
Palmer ' -Statior';';
Atlantic Ocean
ANTARCTIC 44')..4PENINSULA
„.„-!
McMurdoSound
South PoleStation
ANTARCTICA
0 400=ow
Miles
The need to spend money onfacilities probably will crimpmoney for scientific researchBy MALCOLM W. BROWNENew York Times News Service
As the green parkas worn by U.S.Navy men and women in Antarcticarapidly are replaced by the redparkas of civilians, significantchanges are taking place in U.S.Antarctic operations. They're dri-ven by leaner budgets, safety con-cerns, the end of the Cold War andnew priorities in science.
Although it is only 23 years old,the United States' South Pole Sta-tion is sinking under the ice andwarping under the pressure of drift-ing snow and ice crystals. Mountingproblems with sewage disposal,garage space, electricity generation,fuel storage, fire prevention and ahost of other things have convincedexperts that the station needs to bereplaced. But the earliest the sta-tion could be replaced, even if workbegan in the next summer season, is2005.
To restore South Pole Station to asafe condition by 2005 requires alarge investment, independent ana-lysts agree. The money might haveto come partly out of Antarctic bud-gets for research on ozone deple-tion, global warming, ice sheet melt-ing, the birth of stars in distancegalaxies and the search for extrater-restrial life.
So the National Science Founda-tion, the agency that directs U.S.operations in Antarctica, is seekingways to slash the cost of research onthe ice.
One way is to reduce the time sci-entists spend on the continent.Agency officials expect to continuesupporting most active research inAntarctica, but they will encouragescientists to stay home, perhaps forone year out of three, to do their
desk work and computer analyses.Savings would limit scientists
By transferring most Navy opera-tions to civilian contractors in thenext two years, the agency expectsto save $30 million. But a savingthat will be less welcome to manyscientists is a projected reallocationof $20 million in research money,mainly by reducing the number ofscientists working in Antarctica inthe next five years.
The 23-year-old dome at SouthPole Station is settling ever deeperinto the 2-mile-thick ice sheet andposing many safety and operationalhazards. The science foundationplans to dismantle it and ship itback to the United States, erectingin its place a pair of horseshoe-shaped residential and office build-ings expected to cost about $120 mil-lion. They will be mounted on stiltsto prevent the accumulation of drift-ing snow around their bases — alarge problem with the old dome.
Dr. Cornelius W. Sullivan, themarine biologist who has headedthe foundation's polar programssince 1993, thinks that his agencywill win congressional approval forfinancing the new South Pole Sta-tion at the Amundsen-Scott base aswell as preserving the other twopermanent U.S. stations in Antarc-tica: McMurdo Station on RossIsland and Palmer Station near thetip of the Antarctic peninsula. Hesummarized the program's needs ata congressional hearing Thursdaybefore flying to Christchurch, NewZealand, for talks with his counter-parts from Britain, New Zealandand South Africa about cooperationon logistics and ways to cut costs inAntarctica.
To lend support to Antarcticresearch, Secretary of StateMadeleine Albright recently addedher signature to an open StateDepartment letter that said: "Main-
taining an active and influentialUnited States presence in Antarcti-ca serves important strategic andforeign policy objectives. This pres-ence in Antarctica gives us a deci-sive voice in the Antarctic Treaty
system, which is the basis for thepeace and stability of the area."
The letter was sent to Norman R.Augustine, chief executive of Lock-heed Martin Corp. and head of apanel of experts who recently
New York Times News Service
assessed the needs of the Antarcticprogram.43 nations have bases
To date, 43 nations have estab-lished bases in Antarctica under theAntarctic Treaty. Although scientif-ic relations among them are harmo-nious, seven nations — Argentina,Australia, Britain, Chile, France,New Zealand and Norway — havelongstanding and conflicting claims
relinquished.U.S. stations are by far the most
populous on the continent, and U.S.influence is regarded as an impor-tant factor in keeping the peace.
Every dollar the National ScienceFoundation can save for rebuildingSouth Pole Station will be needed.Even if large savings are realized,the foundation might have to closePalmer Station for several Antarc-tic winters. Palmer is the smallestof the three stations, but it is espe-cially important for marine biolo-gists because of the rich variety ofbirds and sea animals around it.
The current interest in the searchfor signs of extraterrestrial life hasraised the stakes for financing U.S.-supported science in Antarctica,including support for Russian pro-grams.
Scientists long have suspectedthat primitive microorganisms liv-ing at temperatures as low as minus100 degrees Fahrenheit between lay-ers of rock sediment in Antarctica'sDry Valleys might have counter-parts on Mars and elsewhere. Duning the past two decades, muchresearch has focused on theseorganisms, called endoliths. Scien-tists also are looking for signs of lifein meteorites found in Antarcticaand thought to have come fromMars.
Recently, however, scientificinterest has focused on a huge lakeof liquid water, 140 miles long and30 miles wide, lying two milesbeneath the ice sheet near Russia'sVostok Station. Russian scientistsand their collaborators have beendrilling deep into this ice.
Because of fears that penetratingthe subglacial lake, called Lake Vos-tok, would contaminate it withmicrobes from the surface, leadersof the international project havehalted the ice drilling a few hun-dred feet above the water. Theyhope that when they have found asure way to prevent contaminationthey will be able to pierce the la:layer of ice and look for primev.forms of life in the lake — fornthat might resemble life in the liuid water that is thought to 1under the frozen surface of Euro)one of Jupiter's moons.
Patientsdo better■in warmsurgery
In decades of operating-roomdisputes, anesthesiologists turnthe thermostat up, and surgeonstry to keep cool at work
By DENISE GRADYNew York Times News Service
Anyone who has ever lain nakedand shivering on an operating tableor come to with teeth chattering in arecovery room knows that havingsurgery is not only lonely but alsocold.
Now research is confirming whatpatients might have suspected.According to a study published lastweek, operating rooms, which usu-ally are kept cool to let surgeonswork in comfort, are too cold formany patients.
The combination of a cool room,anesthesia, intravenous fluids andan open incision can lower a
patient's body temperature by 2 to 4degrees Fahrenheit. In some people,that chill can cause serious heartproblems, the leading cause of deathin patients recovering from surgery.
Simply keeping patients warmduring and after surgery can reducethe risk of heart trouble,researchers from Johns HopkinsUniversity reported in the April 9issue of The Journal of the Ameri-can Medical Association.
"Surgeons and anesthesiologistshave constant fights over the ther-mostat in the operating room," saidDr. Steven M. Frank, an anesthesiol-ogist at Johns Hopkins and directorof the study. "It's been going on foryears.
"The surgeons want it as cold aspossible. We want it as warm as pos-sible for patients. We monitor thepatient's vital signs, and tempera-ture is one."
Operating rooms are usually keptat 65 to 70 degrees Fahrenheit. Any-thing less than 70 degrees puts thepatient at risk for lowered body tem-perature, or hypothermia, Franksaid.
But surgeons often prefer lowerreadings because their work can bestressful and physically demanding,and they tend to get overheated.That problem has worsened inrecent years, he said, as surgeonshave been required to wear water-proof gowns that blood cannot soakthrough to protect themselves -
against AIDS.To gauge the importance of body
temperature in surgical patients,Frank and his colleagues studied 300people who had abdominal, vascularor chest (but not cardiac) surgery.
In 158 patients, routine warmingmethods were used, including paperdrapeg during surgery, warmed cot-ton blankets afterward and warmedintravenous fluids. The thermostatin the operating room was set at 70degrees. Despite those measures,patients became hypothermic, withbody temperatures dipping below 96degrees Fahrenheit; about 98.6degrees is normal.
The other 142 patients were treat-ed the same way with one exception:During surgery and for two hours
afterward, they were kept warmwith a special cover pumped fulheated air, which was adjustedkeep their body temperatures eclose to normal as possible. Coof this type are becoming morwidely used.
The warmer patients fare('after surgery. In the followihours, only 1.4 percent haddiac complications as hearor cardiac arrests, compa6.3 percent of the hypothigroup. Two patients in eF.died, so the death ratesbut patients with comp)to spend more time in 'care.
