Three times, in the company of a research team, I have ascended the ice and snow covered Andes to reside for nearly a week at 18,000 feet. Our colorful collection of scientists was studying various methods to prevent or modify that threat to all who ascend to lofty heights - high altitude sickness, nuisance to some; death to others.
On this trip one of our team would experience the rapid onset of deadly pulmonary edema. Without emergency evacuation he almost certainly would have died, a victim of drowning in his own pulmonary secretions.
Our research team was divided into two groups. I was in the experimental group protected by both of our study drugs, steroids and Diamox. Our patient, one of our younger and more physically fit medical students, was in the control group, not protected by drugs. Although this was a double blind experiment set up purely by chance, there was no way that I, a seasoned family doctor and flight surgeon, could not infer from my brightly flushed face and profound urine excretion that a combination of steroids and diuretic type drug was in my daily pill regimen.
All travelers to altitudes in excess of 10,000 feet should be warned of the danger of high altitude sickness and know of the availability of these helpful drugs. Properly used they can lessen greatly the risk of altitude sickness but never eliminate it completely. The best preventive, of course, is progressive acclimatization, a lengthy process requiring weeks. Occasionally the reality of security, rescue or simply the compelling joy of climbing places people at risk. With today's technology and increased ease of transport, including even ascent by helicopter, the numbers at risk are increasing.
We were at the Camp of the Condors, a small, natural campsite well above the ice and snow level of the Andes.. Our brightly colored tents seemed to attract the resident condors, seemingly more glider than bird, so rarely did they move their great wings. Looking down at the remnants of an ancient Inca highway far below us it seemed impossible that just over two days ago we were boarding our flight at Miami.
Landing at La Paz is an unforgettable experience, not for the alien starkness of the glacier clad mountains in the distance or even for the surprise of a seemingly modern city nestled comfortably in the hills below but for the astonishing lassitude which envelopes you almost immediately after you egress the aircraft.
Today's modern jets are engineered to hold a comfortable 8,500 feet equivalent altitude within the passenger section regardless of flight altitude. Ordinarily on descent below this level the aneroids open allowing cabin air to equilibrate with outside. After landing in most of the world you step out at a comfortable airport altitude of something under 5,000 feet. Not so at La Paz! Here when the cabin doors open you suddenly are at 14,000 feet, the level of the airport. The city of La Paz, your destination after a short bus ride, is 13,000 feet, physiologically not much different!
Your body has the weight of lead; your heart rate increases alarmingly and for some reason the air, even in large gulps, no longer is satisfying. You may wish to help with the luggage but your body no longer is yours to command. You sink into the bus seat with a sigh of relief at the brief opportunity to rest it gives you and you cannot help but notice the unhealthy pallor of all the others in your group. You look at the modern buildings as you descend into the city amazed that a culture like this can exist two and a half miles higher than where you were born. Automobiles and bicycles compete for road space. Children, dogs and chickens scamper about at an altitude you only dreamed of previously.
The management of Hotel Gloriosa was very tolerant of the tendency of some of our climbers to practice their rope climbing skills using the hotel balconies. Other guests were either surprised or not, depending upon their previous experience with Americans. It was here we met our guide and
some of his porters who would load the buses with our equipment for the three- hour trip to Uno. >From there we were to walk miles along the lofty altiplano, then climb the remaining peaks to our destination, high in the clouds.
Porters and burros hauled the gear. We carried what we could, which in many cases was only trail mix and water. I overtook an older porter, bearing a load much too heavy for his aging body. He was seated on a rock, looking distressed. I felt his pulse, completely irregular at 180. He had pushed his body into atrial fibrillation. Even these hardy Peruvians natives have their limits.
That night, comfortable in my sleeping bag despite the bitter cold, I dreaded the possible return of sleep terrors. On a previous trip, without Diamox, my sleep had been interrupted many times by this frightening effect of lack of oxygen on the body's breathing centers causing loss of the normal sensitivity to carbon dioxide. As a result, breathing stops temporarily during sleep allowing heavy buildup of this substance in your blood.
Finally you are awakened by a terrifying sensation of suffocation causing a near panic search for the zipper of your sleeping bag, frantic tearing open of the frozen tent flap and thankful gulping of huge quantities of star-studded night air. Within minutes I calm down and reluctantly return to the warmth of my bag, now fearing sleep. Despite the cold I leave the bag unzipped, no longer is it my trustworthy friend. Its restriction makes it my enemy when suffocation terrorizes my sleep.
But Diamox has protected me this trip. This curious drug has fooled the body by raising its acidity level. Breathing centers are triggered by acid levels as well as by carbon dioxide. As a result I am breathing more deeply and rapidly without even realizing it. Rapid breathing in turn serves to increase the oxygen levels of your tissues and of course this increases your altitude tolerance. An amazing Rube Goldberg sort of effect but it works!
On the negative side, it also works to increase urine output, dragging out critical electrolytes, which may lead to other potentially serious problems for the climber but it does increase altitude tolerance.
On this night while waiting for sleep a strange sound disturbs the silence. My tent-mate's breathing, previously normal, now rattles and wheezes with fluid. I move over and take his arm, it is rigid with apprehension. He has just awakened and realizes his lungs seem to be filling with fluid. As a senior medical student he knows all about pulmonary edema. Here at the Camp of the Condors, far beyond hospitals and emergency rooms, the Specter of Death is pointing his finger at him and he knows it!
Our eyes lock as I reach for the stethoscope. No words are necessary, the wheezing, more audible now as he changes position and unzips his bag says it all. The stethoscope tells me what I already know. Percussion of his lower back as he sits bending forward reveals the ominous flat sound of beginning consolidation of the lower lung fields on both sides. I rouse the others members of our team. Finally we agree on the administration of intravenous steroids and a trial of positive pressure breathing from our limited supply of oxygen bottles but it is no use!
Within an hour it is evident his condition is deteriorating. A team of five hardy souls assembles and prepares for the perilous midnight descent carrying the patient on a makeshift stretcher / travois. They return by evening the following day with the report that our patient is "safely in the hospital". I exchange glances with one of the other seasoned doctors in our team, even in the States no one agrees on the proper management of this condition so the term "safe" is hardly reassuring.
On our third day at altitude we spotted a lone climber from a separate French group walking around and around aimlessly one thousand feet above us. Because his behavior was unusual we went to his aide. We found him confused, incoherent and irrational - victim of altitude - this time cerebral edema. We even photographed his retinas, not wanting to miss a golden opportunity for data collection. Again steroids and immediate descent were vital to his care.
On our next trip we would have the newly developed Gamow bag, with this amazing portable pressure bag our patients could have been magically returned to 12,000 feet within minutes while still resting comfortably at the Camp of the Condors.
A week passes before I see my tent-mate again, still in the hospital with pneumonia in both lungs but recovering rapidly. During that week we had performed exhaustive medical studies on everyone available including the porters and occasionally we pushed our reluctant bodies to still greater heights depending upon each person's physiological reserves and masochistic tendencies.
The benefits of steroids and Diamox were obvious to doctors and physiologists in our group long before the double blind code was broken. Clearly, the group with red faces fared better in every respect than their pale-faced comrades. Previous trips had demonstrated the benefit of each drug separately. This trip demonstrated additional benefit when used together.
Back at La Paz our ordeal was over and it was time to enjoy the many attractions this city and the surrounding country has to offer. Having successfully challenged the Andes, we felt like heroes, on a wonderful high. Now the altitude seemed hardly to trouble us. With a spring to our steps we effortlessly explored the treasures of the Witches Market in downtown La Paz and made plans for Lake Titicaca and Cusco. Already we were thinking of our return next year for further studies.
Duane Graveline MD MPH
Former USAF Flight Surgeon
Former NASA Astronaut
Retired Family Doctor