NOVA treks with a group of Himalayan climbers in their quest to reach the summit of Everest, along the way exploring in never-before-conducted tests how extremes of weather and altitude affect the human mind and body. Why do some people succumb so quickly to the ills caused by high altitude while others do not? Does exposure to extreme hypoxia—or lack of oxygen—take a lasting toll on the mind and body? Images of the brain scanned before and after the expedition may reveal truths about the physical traumas suffered in an oxygen-depleted environment, and give us new insight into why the tallest mountain in the world has claimed so many victims.
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00:00Tonight on NOVA, Everest.
00:04In 1996, eight died in a single day.
00:07Now, NOVA takes you back to explore the effects of altitude on the body and mind.
00:13He had the nerve to walk on Carol's door.
00:16Excellent, David.
00:18And a new drama unfolds.
00:20Will the summit claim a new victim?
00:22What's going on, Ed?
00:23David Charles.
00:24Breathing quickly right now won't help you, Carter.
00:26And I know this is really scary.
00:28Everest, the death zone.
00:50Major funding for NOVA is provided by the Park Foundation.
00:55Dedicated to education and quality television.
01:02This program is funded in part by Northwestern Mutual Life,
01:06which has been protecting families and businesses for generations.
01:10Have you heard from The Quiet Company?
01:12Northwestern Mutual Life.
01:14And by the Corporation for Public Broadcasting and viewers like you.
01:20Five and a half miles above sea level.
01:35The high Himalayas stand fixed against the wind and clouds.
01:39The air is so thin it is not life-sustaining.
01:44Within hours the living begin to deteriorate.
01:49But humans come here and struggle for each breath to stand briefly on the highest point on Earth.
01:58It's a living hell.
02:01The only way to describe it is an utter exhaustion.
02:04You really don't care if you die or if you just sit down and don't go any further.
02:09In 1996, eight people died in a single day on Everest.
02:15Scientists believe many, if not all, of those deaths could have been due to hypoxia or lack of oxygen to the brain.
02:21Judgment becomes impaired, person becomes confused, they don't even know where they are as it gets worse.
02:31People hallucinate.
02:32So all sorts of mental changes can take place as the brain starts to become more and more abnormal.
02:39It's a very slow and arduous process.
02:43You take a step, you breathe, you take another step.
02:46That's all your mind is occupied with, is taking each individual step.
02:53For every six successful summits on Everest, one person will die.
02:58With more people climbing into the death zone above 26,000 feet,
03:03one critical question is how oxygen deprivation affects the brain.
03:08David Breshears, a high-altitude climber and filmmaker, has stood on top of Everest three times.
03:15It's just hard work. Everything about being at altitude is hard.
03:19We go up with the best technology available to us, the best training,
03:23and you can still end up frozen to death at 27,500 feet.
03:28That's what makes Everest, Everest.
03:32David was making the IMAX film Everest last year when a storm claimed eight climbers' lives.
03:38He helped rescue some, but others were beyond help.
03:45He is returning to film and lead an expedition that will explore the effects of altitude on the body and mind.
03:53Everyone thinks that they're thinking very clearly up high, and yet, by virtue of going up into that atmosphere,
04:00you greatly increase your likelihood for making an error.
04:05On the early Everest expeditions, climbers trekked for weeks to get to the base of the mountain.
04:12Today, they fly into a Sherpa village at 9,000 feet.
04:19It will take ten days to ascend the 9,000 feet in elevation to Everest Base Camp.
04:32Base Camp is a temporary city of tents housing 300 people to support nine expeditions.
04:39The accommodations may be crude, but most teams have a satellite link to the outside world.
04:46It looks like there's about 30 people standing there.
04:49David Brashears meets up with his team members, and they scope out the route up the mountain.
04:53Uh-huh.
04:54What do you guys think about the upper part there before Camp 1?
04:57David Carter, from Indiana, is returning to Everest after an unsuccessful attempt in 1991.
05:03We always put ladders there, and that's the toughest part of the whole icefall there.
05:07Ed Visters will be guiding Carter.
05:09Considered one of today's premier high-altitude mountaineers,
05:12Ed has climbed Everest four times, twice without oxygen.
05:16Zangpu Sherpa climbed Everest for the second time on David's last expedition.
05:21He is in charge of the large Sherpa staff that will support the team.
05:25These climbers will take part in a battery of scientific tests that will gauge their performances at altitude.
05:31Ed Visters lives and trains in Seattle.
05:38Two weeks before leaving for the mountain, the climbers joined him at the University of Washington for baseline tests.
05:46Dr. Brownie-Shaney looks for physiological clues that determine who will perform well at altitude.
05:52One determinant is lung capacity.
05:55Is it important to have big lungs?
05:57Yes, it is, because in that regard you can move more air, obtain more oxygen within the lungs,
06:03that then the blood can pick up and deliver to the muscle tissues.
06:06When we breathe in, oxygen molecules pass through the lungs into the air sacs.
06:11Here, purple oxygen-deficient blood cells become revitalized and red with oxygen,
06:16and are pumped by the heart throughout the body.
06:19Dr. Shaney measures the climber's heart rates and ability to work.
06:24Carter is well above average.
06:26At the elite level are Ed Visters and David Brashears.
06:29The elite high-altitude climber can trudge through the snow, break trail, climb up a cliff at their maximum capability for hours.
06:39Getting close.
06:40High on Everest, many climbers approach their maximum heart rate just gasping in the thin air.
06:46Some may collapse, unable to go on.
06:49Good job, good job.
06:52The amount of oxygen in Carter's blood is measured by Dr. Howard Donner.
06:56Carter, this little machine that goes beat next to you is an oximeter.
07:00The top number here is your saturation, which is a measurement of the amount of oxygen in your blood.
07:06100% means that you're completely saturated, which is what we'd expect close to sea level.
07:12As you go higher, this number's going to drop.
07:15This lower number is your pulse.
07:16You see you have a nice slow pulse at 63, which is normal for you resting.
07:20And as you go up in altitude, a normal response is to see your pulse rate go up.
07:25Carter is now given a decreased level of oxygen to simulate going to high altitude.
07:32His body strives to get more oxygen.
07:37As Carter's blood oxygen saturation falls, his breathing increases and his heart speeds up, trying to pump more blood made red with oxygen to his organs.
07:47Over time, more oxygen-carrying blood cells will be produced to carry the oxygen where it is most needed, to the muscles and brain.
07:55These physiological changes are called acclimatization, and they enable a person to survive at high altitude.
08:02You're getting a little bit higher altitude. You feeling all right?
08:05Due to this sudden exposure to high altitude, Carter's oxygen saturation plummets.
08:11He will ultimately pass out from the lack of oxygen to his brain.
08:17We found some abnormalities previously in high altitude climbers.
08:20Dr. Peter Hackett addresses the climbers on the effects of decreased oxygen to the brain.
08:25One of the more pressing questions in high altitude medicine is, does climbing to extreme altitude cause brain damage?
08:32And we're going to be looking at that in a number of ways.
08:34One is by MRI scans.
08:36Some work indicates that some climbers who go to extreme altitude without oxygen do come back with slightly smaller brains.
08:43If cells of the brain actually die, the brain will get smaller.
08:48That's what happens with strokes and other things that cause brain cells to die.
08:51So we'll look at the volumes of the brain by these special scans.
08:55These are unusual people, and they're going to a very unusual place.
08:59So there's some opportunities here.
09:01David and Ed have been to altitude many times,
09:04and we might expect them to react a little bit differently than David Carter,
09:09who is a relative newcomer at these kind of extreme altitudes.
09:13I've lived by the river for 20 years and only twice before...
09:16Psychometric testing will reveal subtle changes in the climbers' abilities to process information as they go higher.
09:22One.
09:23What we will expect to see is that there's a slowing in speech.
09:27There'll be a slowing in reaction time.
09:30We may see a lot of misspeaks.
09:33They won't say things quite the way they would at sea level.
09:38There'll be slurring and hesitation.
09:40This one's a little more difficult.
09:42This time what you're going to do is go down the columns,
09:45and you're going to say the color that you see.
09:47You have to disregard the word you see.
09:50Tell me the color that the word is printed in.
09:53Okay? Go ahead.
09:55Blue, red, green, blue, red, blue, green, red, green, blue, green, blue.
10:05Stop.
10:07That's going to be fun at altitude.
10:09Isn't that fun?
10:10If Charles beats David in a sprint, which man is the faster runner?
10:16Charles.
10:17People like Ed Wiesters and others who make a career out of doing these very high peaks without oxygen may have some long-term brain abnormalities.
10:26Some studies indicate that they do have very minor subtle cognitive dysfunction,
10:31and it can be found only on psychometric testing.
10:34There's nothing obvious.
10:35And their MRI show that there can be structural changes.
10:38We have yet to have a good correlation between the MRI structural changes and the cognitive changes.
10:44That's going to take more time, more studies, more research like we're doing now.
10:51Dr. Howard Donner treks into base camp where he will be stationed to monitor the health of the climbers.
10:57Howard!
10:59You made it!
11:01Man, you're moving like an old man.
11:03Not ready to speak in coherent sentences.
11:05Okay, so go easy.
11:07Welcome to base camp.
11:09Thanks, man.
11:10Nice to see you.
11:11This is Zongbu.
11:12Zongbu.
11:13There's Sirdar.
11:14Nice to meet you.
11:15Hey, good to meet you.
11:16You know, you look blue.
11:17Here, give me your hand.
11:18I got a pulse oximeter here.
11:20I don't trust you with medical devices.
11:21Oh, God.
11:22Look at you.
11:23You're alive.
11:24Okay, good.
11:25You know, your saturation level is 74, and your pulse is about 85.
11:28All right.
11:29A blood oxygen level of 74% would be alarming at sea level, but is normal for someone who has just reached 18,000 feet.
11:37Well, would you like some tea?
11:38Thanks, dude.
11:39We'll get you warmed up.
11:40As Howard acclimatizes over the next few days, the level of oxygen in his blood should increase.
11:46If it doesn't, he may become ill with acute mountain sickness.
11:50The early warning signs of mountain sickness are primarily headache, followed by dizziness, trouble sleeping, and lack of appetite.
11:57And then as it progresses, one develops a more severe headache, nausea and vomiting, and trouble with the balance or coordination.
12:05And that is the hallmark sign of progression to definite cognitive problems.
12:10I've had altitude sickness before, and I know how bad a headache can get.
12:14The two things that really affect you are a shortage of breath and the lack of sleep.
12:21Sometimes you rest, and you feel okay. Then you start walking, and it's not okay.
12:26After my head, it's gone too big like this.
12:30And I experienced the most shocking headache I've ever had in my life, and I felt sick.
12:35And at night time, I took two aspirin. After that, I never failed myself to get a headache. Now I'm fine.
12:42If symptoms get worse, a portable hyperbaric chamber known as a gamoff bag can help.
12:48What's your altimeter say before you get in?
12:50Let's see, we're about 17,600 feet. All right.
12:55The bag is inflated to increase the pressure inside.
12:58This results in a higher density of oxygen molecules.
13:02Doug, why don't you watch your altimeter, and let us know in a moment what it's telling us.
13:07Boy, we're dropping fast!
13:09This simulates a descent of several thousand feet, where the ambient air holds more oxygen.
13:14Doug, what's your altitude?
13:16I'm at about 15,300 feet now.
13:19At this altitude, pumping this bag up to 2 psi will bring a patient down to an altitude inside the bag of about 8,000 feet lower than we are here.
13:29Doug, what altitude are you at?
13:31We're at 10,900 feet.
13:33Most of the time, putting a patient in for a number of hours, they're going to get some benefit.
13:38Let's pretend Doug couldn't walk, because of severe forms of mountain sickness.
13:41We put him in for four or five hours, and now he's able to walk down the hill under his own power.
13:46So that's a big help.
13:47Okay, Doug, I'm going to stop pumping and slowly deflate.
13:52Within seconds, the pressure decreases and the patient returns to 17,600 feet.
13:57Are your ears okay, Doug?
13:58I'm fine.
13:59Good.
14:00So he's back to base camp.
14:01You can tell by the fact that there's no more tension here.
14:04Lakpa, can I have a little tea, please?
14:05Yes.
14:06Thank you very much.
14:07It's 5.30 in the morning here at base camp.
14:10We'll be doing a little filming today with Zongbu.
14:11That's why I'm here.
14:12We got our harness on, our boots, and our crampons.
14:13And those are all our tools for the ice fall.
14:15And so I have to eat and drink and get ready to go.
14:17The Khumbu Icefall is a steep glacier riddled with deep crevasses and huge ice blocks.
14:42It can only be traversed with the use of ladders and rope fixed and maintained by a team of Sherpas.
15:12It is here at the beginning of the climb where the greatest objective dangers on Everest lie.
15:29On this section, four ladders are strapped together to help climbers scale a hundred-foot wall of ice.
15:39Zongbu and David use mechanical ascenders to climb up the fixed ropes.
15:44This is called Jumarang.
15:49The ice fall is a jigsaw puzzle of giant blue ice puzzle pieces the size of houses, weighing some 30 tons each.
15:58Without warning, the blocks can shift, and crevasses cave in, taking climbers with them.
16:08David Jumar is up the last pitch of the ice fall to arrive at Camp 1.
16:13Okay, everybody down there, this is David from Camp 1, ready to proceed with the high-altitude tests.
16:21And I wanted to start out with giving you my current pulse oximeter reading.
16:26Do you copy, and how are you down there?
16:29We copy, and we're ready to record your pulse oximeter readings. Over.
16:33Hi, Jenny. We really miss you up here.
16:36I'm going to stick this thing on my finger, so stand by.
16:39My heart is racing because I have to take this damn test up here.
16:44I'm nervous as hell. Oops, it just went up.
16:48So, Jenny, I have it on my finger. The oximeter reading is 80.
16:55A more realistic reading for my pulse was, a few minutes ago, it was 78.
17:01But now that I have to take this test and I get all this test anxiety, my pulse is racing at 104.
17:07Green, red, blue, red, green, red.
17:14Along with Ed Visters, David Carter has also reached Camp 1.
17:18Carter, this is true and false. I just want you to read the number of each question
17:22and tell me whether it's true or false. You have 60 seconds.
17:25You can go. 51 is false. 52 is false. 53 is false.
17:3654, false. 55, false. 56, true. 57, false. 58, false. True. 58 is true. 59, true.
17:54Oh, hi, Ed.
17:55Hi.
17:56Have a good sleep?
17:57Yeah.
17:58Guess where we're going.
17:59Base camp.
18:00Base camp.
18:01Yeah.
18:02Yee-haw.
18:03Oxygen.
18:04Warmth.
18:05Cotton clothing.
18:06Wow.
18:07Shower.
18:08Shower.
18:09Oh, hell.
18:10It's just down there.
18:11Oh, it's just down there.
18:13Yeah.
18:14We're good.
18:15Yeah, we're good to sleep.
18:16Yeah.
18:17We're good to sleep.
18:18Yeah.
18:19Yeah.
18:20Guess where we're going.
18:21Base camp.
18:22Base camp.
18:23Yeah.
18:24Yeah.
18:25Yee-haw.
18:26Oxygen.
18:27Warmth.
18:28Cotton clothing.
18:29Wow.
18:30Shower.
18:31Yeah.
18:32Hell, it's just down there.
18:38At the top of the icefall, there is a bottleneck of climbers.
18:41Ed Viesters puts on his pack at the back of the line.
18:47It's amazing, you know, you're on Mount Everest and you're waiting in line like this.
18:52It's only one at a time on the ropes.
18:54Ed, David and Carter, all descend back down to base camp from Camp 1.
18:59This will be the first of many trips through the icefall in their long schedule of acclimatization.
19:06It takes time for the body to adapt to higher and higher altitudes.
19:10Climbers will typically ascend to Camp 1 twice from base camp.
19:15They move up to Camp 2 and sleep there several nights before moving to Camp 3.
19:20Before their final push to the summit, climbers descend to base camp to rest and gain their strength before trying for the summit.
19:30While climbing down through the icefall, the climbers cross paths with a line of Sherpas bearing loads for the higher camps.
19:38Sherpa is the name for the indigenous people who live in the Everest region.
19:45Although they adapt well to altitude, they're not immune to its debilitating effects.
19:49If they push themselves to go up too quickly, they too can suffer from acute mountain sickness.
19:57At base camp, the climbers hear the disturbing news of a Sherpa who was found near death lying in the middle of the trail.
20:03When I saw him, his eyes, his pupils were fixed and dilated.
20:09He's barely had a pulse and he died several minutes after I got there.
20:14I think he had high altitude pulmonary edema.
20:16With pulmonary edema, the blood vessels in the lungs start to leak.
20:22They leak this plasma fluid that is tinged with red blood cells, so it's a little pinkish.
20:27And the air sacs start to fill up in different parts of the lung, usually the right first and the left.
20:32And eventually, they all fill up with fluid.
20:35The person starts coughing in this pink, frothy sputum, can't get any air at all.
20:38Their blood oxygen level drops and they go into cardiovascular collapse and die.
20:44With each breath, he was blowing bubbles through the fluid in his nostrils and mouth.
20:51He was drowning in his own secretions from high altitude pulmonary edema.
20:58The treatment is descent.
21:01If the patient can't walk, then oxygen or a gamoff bag must be used.
21:04Lagpa, hi. Can I check your saturation again?
21:09A Malaysian expedition doctor measures the sick Sherpa's blood oxygen saturation.
21:14But on oxygen, he's now got a saturation of about 91%, which is considerably different than what it was yesterday.
21:22This morning at breakfast, we noticed a team carrying this sick Sherpa, this is Lagpa, by our camp.
21:28And we're now at the helicopter landing zone with Dr. Sehak Koo.
21:32Sehak, what went on with Lagpa?
21:36Well, he was very ill indeed when we came across him.
21:40He was a bit confused. He was quite ashen grey.
21:44He was quite breathless as well.
21:46And we checked his saturations and to my alarm, it was 20%.
21:50We slapped some oxygen on him and it came up to about 70-80% with three or four litres a minute.
21:55And because he was able to tolerate lying flat, we decided to put him in the gamoff bag, which we did for two hours.
22:02And how did he respond to the gamoff?
22:03He did very well. He was comfortable in it, but the fact that he had symptoms on both sides of his lung and the fact that he was so unwell and so desperately short of oxygen, we treated him for palm reedema.
22:15When a helicopter arrives at base camp, it means a person is in need of immediate evacuation.
22:23And for Lagpa, a quick descent to Kathmandu will save his life.
22:28Pilots don't hesitate long here and they breathe supplemental oxygen.
22:32If suddenly exposed to the altitude of base camp, the pilot could become desperately ill from acute mountain sickness.
22:45In the early morning freeze, the climbers silently put on their crampons to climb up through the icefall for the last time.
22:51The team has been on Everest for several weeks, acclimatizing at the higher camps. Time is running out for an attempt on the summit.
23:10Carter has developed a high altitude cough, which he knows could jeopardize his chances of completing the climb.
23:21It's a real violent cough. It comes from deep within and you can't control it.
23:28My main concern right now is when I get higher, the cough will get worse and I'm worried about breaking a rib or vomiting or something.
23:36A chilling reminder of how dangerous Everest can be. Human remains resurface from the depths of the moving icefall.
23:47We came upon this the other day in the glacier. It's the obvious remains of a climber spread out around this area.
23:54This is an inner boot made out of a synthetic material, making it probably 80s vintage.
24:00And there's still portions of the bony structure of the foot inside.
24:03Right here, maybe the most obviously human portion of this skeleton is the head of the femur.
24:13And over here, a tibia and a fibula still intact, still together.
24:17And this kind of stuff is spilling out all the time and a reminder of some of the drama that goes on up in the icefall.
24:24The climbers bypass Camp 1 and enter the Western Coombe on their way to Camp 2.
24:32This high glacial valley is transected by massive lateral crevasses.
24:37This is when you're looking at SPF.
24:38This is why not a little tiny bit.
24:39This a little bit of a fumigal valley is a trope.
24:40And here, were you roughly the sipping.
24:41This is where the netстранras m or the ai-pia is still burning in the icefall.
24:42It's a little bit of a ton ofissimoiton.
24:43However, that is only one that makes the slope to the ceiling and the fort.
24:44This is not that the ham and the volcano is not идеal, but a bit of a bit of a bit of a bit of a bit of a bit of a bit of a bit of a bit of a bit of a bit of a bit of the is a building.
24:46It's not a bit of a bit of a bit of a bit of a bit of a bit of a bit of a little bit of a bit of a little bit of a bit of the mett.
25:17How are you feeling, Ed?
25:21Oh, pretty good. It was a long day.
25:23It's about 12.30. I started at 5 a.m.
25:28So it's been a long day.
25:29Where'd you start from?
25:30Base camp.
25:32Don't you have something really fun to do today?
25:34No, nothing fun.
25:36Just relaxing.
25:37I thought you were going to do some testing up here.
25:39Oh, yeah, we've got to do some testing. That's right.
25:41What kind?
25:42Oh, mental testing. Reading some lists and memorizing and stuff like that.
25:47What do you think you're going to do?
25:48I have no idea. We'll soon find out.
25:50Okay, Carter. The action of the brave cyclist kept the small boy from being hit by a 10-ton truck.
25:57The action of the brave cyclist kept the small boy from being hit by a 10-ton truck.
26:03If Daphne walks twice as fast as Margaret, and they are the only two people in a race, who is most likely to finish last?
26:12Margaret.
26:13Okay, now you know for this test, David, you're going to try and count the low tones and ignore the high tones.
26:19Ready?
26:20How many?
26:28Four.
26:30Today I'm suffering badly. We're up at 6,500 metres.
26:34And often one feels fairly poorly here anyway.
26:40I think I was suffering from AMS, acute mountain sickness, which with vomiting and diarrhoea means that I couldn't drink or eat anything.
26:53So I'm feeling a bit weak.
26:54This is the part of high altitude mountaineering that isn't nice, being sick.
27:01It's hard enough as it is, but when you're sick as well, all your reserves are gone, and it's very hard to catch up.
27:11If Guy Cotter's symptoms get worse, he'll have to descend.
27:17There is a delicate balance between acclimatisation and physical decline.
27:21Climbers know that they can only stay at altitude for so long.
27:27You know, I'm nervous. I don't know how I'm going to perform.
27:30I'm also nervous that we're sitting down here, and my body is slowly deteriorating the longer we stay at this altitude.
27:38And I slowly get weaker and weaker.
27:42Humans will start to deteriorate because of the high altitude at around 17,000 feet.
27:47Sleeping becomes a problem.
27:49Muscle wasting takes place.
27:51Weight loss takes place.
27:52This process of deterioration takes place much more quickly the higher altitude that one goes to.
27:58So at over 26,000 feet, it's called the death zone because acclimatisation is essentially impossible.
28:05We're going to camp 3 tomorrow. We're going to get up early.
28:17Around, we're going to get out of here probably about 6 o'clock.
28:21I'm on an antibiotic now.
28:23I ended up getting a pretty good head cold about 3 days ago.
28:27And yesterday, I was really feeling pretty bad when I came into camp 2.
28:32I was dehydrated and basically just weak from the cold.
28:37But the antibiotics have been kicking in, and I'm feeling pretty good today and looking forward to going tomorrow.
28:48In the morning, they march to the top of the western Coombe, where they begin the arduous ascent of the Lhotse face.
28:59Hey, David, you can start anytime.
29:02Carter to Bates, do you copy?
29:07Hey, this is Bates. Where are you guys? Over.
29:10Hey, Doc. It's Dave.
29:12We're at basically the bottom of the Lhotse face, where our elevation is at 22,300.
29:22And it's about 8 o'clock in the morning.
29:25We got that, David.
29:26How are you feeling overall? Over.
29:29Oh, not too bad. I could be feeling a little bit better right now.
29:32We're going to need the oximetry data if you have it. Over.
29:35Uh, pulse is around 140 when I rolled in.
29:39And, uh, blood oxygen saturation with...
29:4360. Over.
29:4460% is low, but Howard is hopeful that Carter's saturations will improve over time.
29:53David Brashears interviews Carter an hour below Camp 3.
29:56How does it feel?
29:59Ah, it's tiring. I feel I felt better.
30:05What's it like climbing at altitude?
30:07Ah, you know, it's slow.
30:10You're winded, dehydrated, losing your voice, coughing, but the views make it worth it.
30:22Camp 3 sits halfway up the Lhotse face, a 45-degree wall of glacial blue ice.
30:28Okay, let's huff and puff it up here.
30:31The pace is slow as Ed and Carter ascend into thin air.
30:35The route is fixed with ropes, and they fall into the rhythmic movement of kicking steps, pulling, and stepping up.
30:45Climb that Camp 3.
30:47Yeah.
30:48Good job.
30:48It's good to be here.
30:51We've got to get some, uh, some snow and melt some water for those guys coming up.
30:56Be careful walking around here, though. It's kind of steep, especially without crampons on.
31:00Yeah.
31:00Many climbers have died here, slipping off the face from one poorly placed step.
31:09Don't you think this is a little absurd?
31:12I'm sitting on this little ledge out here in front of my tent at 24,000 feet.
31:18I'm ready.
31:19The video camera captured the bank robber's daring daylight robbery of the First Avenue Bank.
31:24The video camera captured the daring bank robber's robbery of the First National Bank.
31:33The action of the brave cyclist kept the small boy from being hit by the 10-ton truck.
31:41The action of the brave cyclist, um, help, uh, save the boy, uh, let's see, I know I have to say all I know, uh, prevent the boy being hit by the 10-ton truck.
31:58Oh, shit.
32:00It's just hard work. Everything about being at altitude is hard.
32:07I can't show you that there's no oxygen molecules in the air here.
32:11There's only 35% of the oxygen you're breathing down there at sea level available to me right now.
32:17We have to finish this expedition.
32:19The icefall is going to close.
32:21Our permit's up.
32:22We've been here a long time, but we're also extremely cautious, and we're not going to push it one bit.
32:29We'll do our research as high as we can and go home, uh, knowing we've done the best we can.
32:38Whoa.
32:39How'd you sleep?
32:41Good.
32:42Good.
32:46Yeah, the oxygen really helped.
32:48Oh, it was great.
32:52Oh, yeah.
33:01Carter, this is Howard.
33:04How do you feel your breathing's going relative to this upper respiratory infection?
33:08Over.
33:09Real good now.
33:10A lot better.
33:11Howard, it was a lot worse when I was, uh, you know, I'd wake up after two hours and I felt like I had a lot of shit in my throat, and I'd cough it up.
33:19It was kind of a hard chunk, snot-type shit.
33:22It was yellow.
33:23Over.
33:24It sounds like maybe you're clearing this stuff out.
33:26Over.
33:27Yeah, after a few hot drinks and, uh, getting off O's and, uh, breathing through my nose, uh, I feel a lot better.
33:36Great, dude.
33:37I don't need to tell you this.
33:38Just stay hydrated and cough that shit out of there.
33:40I'll give you back to Kate.
33:41All righty.
33:44Hey, where are you now?
33:47I don't know.
33:49No, I'm kidding.
33:50We're at Camp 3.
33:51We're getting ready to move out.
33:54Carter is about to go higher than he has ever been before.
33:57Looking up the route, some 50 climbers clamber towards the highest camp on the mountain.
34:05This makes David Brashears and Ed Visters very nervous.
34:10They witnessed last year that crowded ropes on Everest can be deadly.
34:17This year, it seems nothing has changed.
34:19As climbers wait their turn on the ropes, they increase their chances of becoming hypoxic.
34:28Tonight, they will all leave camp and climb toward the summit.
34:35David and Ed climb into the death zone, an altitude where humans are only transient visitors.
34:44The tents of Camp 4 finally come into view.
34:46It has taken nearly two months for the climbers to reach this point.
34:51And what will transpire over the next 24 hours will change their lives.
35:01Oxygen bottles from expeditions years ago litter this wind-scoured place.
35:08Highest junkyard in the world.
35:10Anything you need, we got it.
35:14Temples.
35:16Spare oxygen.
35:18Spare oxygen.
35:21Ten stakes.
35:23And the odd corpse.
35:28When you die at 26,000 feet, no one has the energy to carry your corpse off the mountain.
35:34The climbers are slowly deteriorating.
35:37Their bodies literally consuming themselves for energy.
35:40You need the red string?
35:42Okay.
35:42Simple tasks take longer to perform, and precious energy is burned just gasping for air.
35:50While most climbers are resting, David, Ed, and Carter endure another round of psychometric tests.
35:56Old houses are more difficult to maintain, but are worth the extra time and effort.
36:03Old houses are more difficult to maintain, but are worth the extra effort.
36:08Ed, I've lived by the river for 20 years.
36:11And only twice before in all those years has it been this high.
36:16Ed lived by the river for 20 years.
36:21And this was the first time it had been this high.
36:28Over.
36:31Oh, boy.
36:33The wildflowers bloomed in profusion in the high meadows in August.
36:37The wildflowers bloomed in profusion in the high meadows in August.
36:42David radios Ed, who is in a nearby tent.
37:00The scene feels all too familiar.
37:03Ed?
37:04I just tuned in.
37:06What's going on?
37:09I'm having serious doubts about going up today.
37:14Something about climbing with all these people.
37:17It's got me bothered in the way that a few days last year had me bothered.
37:22What do you think?
37:24It does concern me.
37:25There's a lot of relatively inexperienced people.
37:28Hopefully, nobody's going to get in trouble.
37:30If they do, of course, the more experienced people always have to help out.
37:37And then who looks after who up there?
37:39You know, how do you sort that out?
37:41Well, I don't like to be around people staggering around like that.
37:44And I don't know.
37:46I'd like to see this day just kind of sort itself out without me in it.
37:51It's a brief moment of doubt.
37:53But in the end, David decides to go up, knowing he can always turn around.
37:57Five hours later, the climbers prepare for their departure.
38:03At this altitude, loading a pack and putting on crampons will take two hours.
38:09Each climber carries two bottles of oxygen.
38:12They leave at 10 p.m.
38:13When one considers the condition that a climber is in on the South Pole on summit day,
38:19it's really amazing that they can reach the summit at all.
38:23First of all, there hasn't been sleep for usually a couple nights.
38:27There hasn't been enough to eat or drink.
38:30Even if they've been on oxygen, it's still been very uncomfortable to breathe.
38:34The mucous membranes are all dried out.
38:36There's always a sore throat.
38:38There's always a cough.
38:39There's often a headache.
38:40And it takes a tremendous amount of will to keep going under these conditions.
38:47At 5.30 in the morning and 300 feet below the summit, David calls down to Howard.
38:54We've been climbing like crazy.
38:56We're on the South Summit, 28,700 feet.
39:02It's unbelievable.
39:03And you climb in the middle of the night and you're standing up there in the early morning.
39:06They sit down to rest.
39:09Ten feet in front of them lies the body of Rob Hall, one of the expedition leaders who died in 1996.
39:16David points to where Rob is buried under wind-driven snow.
39:20How far buried do you think he is?
39:23Five feet?
39:23Five.
39:24Could be five or six feet.
39:25Right.
39:26That's a lot.
39:26Yeah.
39:29Rest in peace.
39:34They have only 300 vertical feet to go, but two hours of climbing.
39:43They traverse a knife-edge ridge which drops off 8,000 feet on both sides.
39:49David climbs in front.
39:50They reach the Hillary Step, a 40-foot wall of exposed rock.
39:58This is the most technical terrain on the summit day.
40:01Climbers maneuver up the cracks and over the rocky outcrop while clipped into the fixed ropes.
40:08Carter hoists himself up.
40:12Only one climber can ascend at a time.
40:16This is where bottlenecks occur.
40:17They silently pass by the body of a climber from an earlier expedition who died here on the ropes.
40:35The breathing becomes unbelievably difficult.
40:39You feel like you're one huge lung.
40:42The heart rate at rest becomes higher and higher.
40:45The maximum heart rate becomes lower and lower.
40:48And as you go higher, those two get closer and closer together.
40:51And of course, when your resting heart rate equals your maximum heart rate, all you can do is rest.
40:56You can't do any more physical work.
41:01They've climbed for nine hours.
41:04Zhang Bu raises the Tibetan flag on the summit.
41:07David is sitting on the top.
41:09Ed is taking the last steps up with Carter just behind.
41:12David, we read you loud and clear.
41:19Where are you over?
41:22Howard.
41:24I'm on top of the world.
41:26We made it.
41:27I'm on the summit of Mount Everest.
41:2929,028 feet.
41:32I'm here with David Carver.
41:33Ed Beasters.
41:35I can see everywhere.
41:37It's just so beautiful.
41:39I'm not going to be able to stay here very long.
41:41David Brashears has reached the summit of Mount Everest for the fourth time.
41:47Ed Beasters has now become the first non-Sherpa to climb Everest five times in return.
41:53Rob Hall's fifth summit last year was tragically his last.
41:58Carter has lost his voice and will be unable to take the world's highest psychometric tests.
42:03Mike walked around the block three times before he had the nerve to knock on Carol's door.
42:09Mike walked around the block three times before he had the nerve to walk on Carol's door.
42:16Excellent, David.
42:17Do you have any oximetry on the summit?
42:20I'm at 78.
42:23Sitting on top of Mount Everest.
42:25At 78, David's blood oxygen saturation is good for a climber breathing supplemental oxygen.
42:31Climbers consume bottled oxygen in a flow of two liters per minute on the summit day.
42:35With his mask off for a few minutes, David's respiratory rate increases significantly.
42:40David, what's it like climbing back in the same area that you were in last year?
42:45Over.
42:46All the bodies that were there last year were covered, but unfortunately, we did pass one
42:53body right on the fixed ropes.
42:55It only makes me question my sanity and why I climb this mountain again, because it is dangerous
43:02and cold.
43:05Ed takes his final psychometric test on Everest.
43:08The man who was an engineer came to the store where Alice worked to buy pastries.
43:13Who bought pastries?
43:20Uh, the engineer, Jack.
43:22The guy.
43:25Where went Alice?
43:28In the store.
43:29Ed, I know you want to get moving again.
43:31Let us know how you're doing.
43:33How you feeling?
43:33Over.
43:34I feel fine.
43:36Get back cold.
43:37The descent is quite arduous.
43:41You're physically spent.
43:42You have to think about what you're doing.
43:44You can't just stagger and slug your way down.
43:48A lot of accidents and mountaineering occur on the descent, and it's because people get
43:52to the summit and they're totally let down their guard, and they've used all of their
43:55energy just to get to the top.
43:58It takes five hours to climb down to Camp 4.
44:01In the safety of his tent, David reveals to Howard that he had a difficult climb to the summit.
44:08Howard, this is South Cole.
44:11Hey, David.
44:11This is Howard.
44:12Go ahead.
44:12This morning, I drank about a quart of Kool-Aid.
44:16Then I stopped, and I threw up about six times.
44:23I thought I would have to come down, but I didn't want to leave the team behind because
44:28it was just, I kept thinking I'd feel better.
44:31I had the worst trip down in the South Summit I've ever had.
44:37Over.
44:38I got that, David.
44:39How's everybody doing?
44:40Over.
44:42We've got to get these guys out of here.
44:43He's a little sick.
44:44David Carter's condition has worsened.
44:47Despite his own illness, David Brashears picks up the camera to shoot Ed taking care of
44:51Carter.
44:52Tell me what's up.
44:53He's at 93 and 133, so your pulse ox is really good.
44:58Your throat feels real constricted.
45:00Yes.
45:01Okay.
45:02He's on four-liter flow.
45:04David started having problems coming down in the South Summit.
45:07Couldn't catch his breath.
45:09So we called the doc at base camp, told him what was going on, and he doesn't know whether
45:15it's something like pulmonary edema or possibly the fact that David was having some lung infection
45:24earlier on that he's been fighting, and whether the altitude just exacerbated that.
45:29So I think the best option, if he can handle it, is to get him down to camp two.
45:34The lower we get him, the better.
45:36What about the oxygen at camp two?
45:39Yeah, there's a bottle.
45:40They have just climbed to 29,028 feet, the summit of Everest, an exhausting accomplishment.
45:47Now they will try to descend 5,000 more feet to get Carter to a safer altitude.
45:52Hey, David.
45:53Good luck, man.
45:54Sorry you had to get sick like this.
45:56David Brashears stays at camp four to rest, as Ed accompanies Carter.
46:01He would go 10 or 20 feet, and then we'd stop for five minutes.
46:06You know, he'd have to catch his breath.
46:08He'd have to take his mask off.
46:09He was overheating, desperately trying to gain control of his breathing.
46:17I thought we could get to camp two, but as it turned out, it took us a long time.
46:22It took four and a half hours to get down to camp three.
46:26So it was about 7 p.m. then, and we got into the tent, and that's when it started to get a little hairy.
46:32After hours of labored breathing, Carter gains enough strength to get on the radio.
46:38Carter, my man, how are you doing?
46:42I'm still alive.
46:44It's been a hell of a day.
46:46Tell me, this is very important, Carter.
46:50I need to get a feeling for whether you feel like your lungs are full of fluid.
46:54Do you feel like it's difficult to get air?
46:57Do you feel really short of breath?
46:58Or do you feel more like it's wheezy in your upper airway, like you have asthma?
47:03Over.
47:03Carter seems to be improving.
47:30But two hours later, a desperate call from Ed.
47:37What's going on, Ed?
47:42Ed, I'm going to keep talking.
47:43You don't have to respond.
47:44See if you can do a Heimlich and get him to expel whatever is obstructing.
47:49Over.
48:00Okay, Ed, listen to me.
48:04I'm not sure where you're at.
48:05If it's an obvious obstruction, you can push it out with a Heimlich.
48:08Do that.
48:09If it just seems like Carter's airway is closing and you need to breathe for him, go ahead and
48:14start mouth-to-mouth ventilation.
48:17Over.
48:17Tell me what Carter's doing now.
48:26What is his respiratory status?
48:27Over.
48:27Over.
48:28He's sitting up.
48:30We did some more Heimlich.
48:31It seems like he's calming down a little bit.
48:34Hang on.
48:34Okay, what's very important, Carter, for you is I want you to take nice, easy, slow, deep
48:41breaths.
48:42Breathing quickly right now won't help you, Carter, and I know this is really scary.
48:46You're going to do fine, but I need you to breathe deep in and out and in and out slowly
48:54and know that Ed and the rest of us are going to take care of you.
48:57Over.
48:57Over.
48:58David was desperately gasping for air.
49:03I wasn't sure he was going to make it through the night.
49:04I mean, he had his doubts, and it's a scary situation to be up there all alone, thinking
49:10that, you know, here this guy might die on you.
49:19Here we go.
49:19Looks like we have a record level.
49:22That light came on.
49:23That's plugged in.
49:25Okay, David.
49:26What's going on?
49:28It's been a long, it's been a really long couple days for me.
49:34I've been very sick coming down.
49:36I'm totally exhausted without having problems getting a full breath.
49:41My throat feels like I'm breathing through a straw right now.
49:47This is God's gift up here.
49:51That was the first time in my life when I literally thought I was going to die.
49:54I still, to this point, have not even thought of summoning.
49:58I just want to get down the mountain.
50:00I'm choking to death at 23,000 feet.
50:05The first thing that went through my mind was how isolated I am, and I'm not going to be
50:11rushed to a hospital and revived.
50:13I knew that when I was choking, there's just two people there with myself and Ed, and it was frightening.
50:21I don't want to die.
50:23I don't want to die in the mountains.
50:24I don't want to die young.
50:25But, since I've survived it, it's a big part of my life now.
50:38Ten days after coming off Everest, the climbers returned to Seattle for a final session of testing.
50:45The scientists have now had a chance to analyze the data.
50:50The pulse oximetry data collected on this expedition showed, as expected, the decline in oxygen with higher ascent to altitude.
51:00And David Carter, in particular, had lower blood oxygen levels, which seemed to go along with some of the problems he was having on the mountain.
51:06And we need to do more careful analysis of the relationship of the pulse oximeter readings to the MRI scans.
51:15Dr. Hackett has looked closely at the MRI scans, searching for abnormalities.
51:20He discovers that exposure to extreme altitude can leave its mark on the human brain.
51:26Climbers without oxygen.
51:27Hackett addresses the climbers.
51:28And, actually, the only abnormality we found was a very mild atrophy in the brain of Ed Wiesters,
51:34who is the one that has climbed many times to high altitude without supplemental oxygen.
51:39And, what we'd like to do is follow him over a longer period of time to see if this is something that might actually progress with his high-altitude career.
51:47Ed lived by the river for ten years.
51:51Oh, boy.
51:52And, uh, this was the, uh, first time it had been this high.
51:57Over.
51:59Oh, boy.
52:04Oh, man.
52:08You were feeling bad there.
52:09We have reviewed all the tests, you see, and you can see that there's a real difference in your performance, uh, at high altitude.
52:18At the higher elevations, you're obviously in survival mode.
52:21From the numbers, we could see that your performance was deteriorating.
52:25And, had we had those numbers available, we would have probably suggested that you might not want to continue.
52:31I'm shocked.
52:32And, I, I realize now how sick I was.
52:37And, I, you just, you don't, it's just a haze up there.
52:40You can't tell up there.
52:41No.
52:41We're all just getting by.
52:42Yeah.
52:43I'm looking at David for the first time at Camp 4, and, uh, typically, you know, I'm talking to him on the radio, and, in fact, you saw when he was coughing, he had the microphone off.
52:53Mm-hmm.
52:53So, I'm hearing his responses.
52:55I'm not watching him cough or seeing how awful he looks.
52:58The question, then, we ask is, what happens if you're in an emergency situation?
53:04Are you able to think quickly?
53:05Are you able to think clearly about what you need to do to survive and get down?
53:12You can see how, in his condition, he could have not tied his rope correctly, not tied into his harness correctly.
53:18Right.
53:19Not clipped into the anchor correctly.
53:22I love this mountain.
53:24I, I have learned a lot.
53:26I, you know, I summited, but I still don't even think about the summit.
53:31I'm still thinking about that night at Camp 3, being near death, possibly dying.
53:37When I passed by the last ladder in the icefall, I knew that I had survived Mount Everest.
53:44David, uh, we're curious, now that you've been to the top, you think this was your last trip up this mountain.
53:59Over?
53:59Well, it's the hardest day I've ever had on the mountain, and I have no intention of ever going to the top of Everest again.
54:09I need lots of people to prevent me from changing my mind.
54:12Take the test yourself.
54:31See the 360 views from the top, return to Everest, and experience everything with the extreme altitude.
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56:44Yes.