Asian GEOgraphic

Asian GEOgraphic magazine is an entertaining publication, and quite beautiful. I was just introduced to this magazine, and am very impressed. According to the publisher, John Thet, the magazine was established in September 1999 to bring readers news and stories about Asia, with a dedication to environmental, conservation and wildlife issues. The volume I just reviewed, No. 47, Issue 8/2007, is typical of the publication, as it covers a diverse number of topics and is lavishly illustrated with high quality and entertaining color images. While the articles do not go nearly to the depth of the more well-known U.S. National Geographic, this magazine will appeal to persons interested in Asia, and who wish for a bit lighter reading.


The publisher has also created Asian GEOgraphic Journal, which is a compendium of "101 Things to Do in Asia." It is an equally colorful book and a nice enticement to travel and explore in that part of the world. From mountain climbing in China to paragliding in Nepal to horse trekking in Mongolia to white water rafting in Myanmar, this tidy and colorfully pictured book is a siren call for adventurers who love the outdoors. For financial reasons (I presume), the back matter of the book is a Gear Guide of advertised products, which I imagine will remain static and become outdated. But no matter, the meat of the book is up front, and therein is the reader beckoned to visit far-away places and enjoy the thrill of a lifetime. Adventures, Festivals, and Nature, for certain.

Tags: Asian GEOgraphic,wilderness medicine, outdoor medicine, healthline

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Speeds Associated With Skiing and Snowboarding

Traumatic brain injury (TBI) is a serious event that usually follows a direct blow to the head. It is a dreaded situation that is of concern to skiers, snowboarders, climbers, mountain bikers, and others in outdoor sports situations. There are numerous injury prevention strategies, but none more important than minimizing the situation of risk and wearing a helmet.

Ski season is upon us. In Volume 18, Number 2 (2007) of the journal Wilderness & Environmental Medicine appeared an article entitled "Speeds Associated With Skiing and Snowboarding," authored by Robert Williams, MD and coauthors. In the article, the authors note that current helmet use among skiers and snowboarders remains low, particularly among adults. While it is currently accepted that the benefits of wearing a helmet include increased warmth and protection from face and scalp bruising, scrapes and cuts due to collisions with skis, boards, skiers, boarders, and other objects (e.g., dwellings, trees, and lift poles), there is some controversy about how useful are helmets during high speed collisions. It is felt that as the velocity of impact increases, the utility of a helmet diminishes, which makes sense. In terms of a number, 15 miles per hour has been mentioned as the speed above which a person cannot expect much benefit from wearing a helmet.

However, as the authors note, skiers and snowboarders have many reasons to be moving more slowly - while negotiating turns, choppy terrain, terrain parks, traveling through the woods or in backcountry areas, etc. Therefore, a helmet might be expected to be useful in these situations. With this thought in mind, they looked at determinations of skiers' and snowboarders' speeds using radar guns. Because of limitations involving the use of the radar guns, any speed less than 11 miles per hour (mph) was recorded as zero, and any speed of 11 mph or greater was recorded accurately. Their findings were that in the majority of instances, both skiers and snowboarders traversed "nontraditional terrain" (e.g., turns, out of bounds, in the trees, etc.) at relatively slow velocities. In 87.6% of observations, the measured speed was below 15 mph. So, one would expect a helmet to be of benefit for these skiers and snowboarders should they suffer a fall or collision.

The authors further noted that a helmet might provide protection to a skier or snowboarder in the backcountry caught in an avalanche. Although most deaths in an avalanche situation are due to asphyxiation, there are associated head injuries that might be lessened or prevented.

There doesn't seem to be any significant safety argument against wearing a helmet while skiing or snowboarding. That is, there is no evidence that wearing a helmet encourages risky behavior or increases the incidence of an associated neck injury. The authors comment that the medical community has been slow to endorse the use of helmets for skiing. Not this doctor! As an emergency physician, wilderness medicine expert, and member of the national medical committee for the National Ski Patrol System, I strongly encourage all skiers and snowboarders, including NSPS and volunteer patrollers, to wear helmets when they are skiing and boarding.

photo courtesy of www.skileb.com

Tags: injury,injury prevention,skiing,snowboarding, helmet,speed, wilderness medicine, outdoor medicine, healthline

Labels: accident, helmet, ski, skiing, snowboard, snowboarding, speed

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Merry Christmas and Happy Holidays

Merry Christmas and Happy Holidays to all of my readers. I wish you fantastic adventures, excellent health, and good fortune for 2008 and beyond. Enjoy the outdoors - be safe and have fun. To my family and friends, thanks for all of your support. Take time this coming year to do something special for your fellow man, and be with your families as much as you can.

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Travel Medicine - Tales Behind the Science

Travel Medicine - Tales Behind the Science is a new book published by Elsevier. Edited by Annelies Wilder-Smith, Eli Schwartz and Marc Shaw, it is an interesting compendium that introduces the reader to the specialty of travel medicine with a collection of historical accounts, medical tales, and opinion pieces from a well-respected group of travel medicine practitioners.

From the publisher: "Travel to exotic places is fascinating, and equally so are infections and other dangers of exotic travel. Moreover, one need not be traveling to suffer these maladies; sometimes they travel to you. The enormous global mobility demands a public health response. The result is the concept of 'travel medicine' as a separate discipline. This book describes the evolution of travel medicine, travel vaccines, malaria prophylaxis and infections of adventure and leisure.

This book is unique and different to the standard textbooks on travel medicine. It provides rare insights into many of the behind-the-scenes in travel medicine, personal stories of failures and successes of travel medicine practitioners, the 'real life' tales that unravel the science behind travel medicine. We believe that the best lessons are learned from personal stories.

Not every travel is fun. Some travel is for a cause, be it religious or humanitarian, or be it to escape certain political systems. We have added stories on the tragedies of so-called 'undocumented refugees,' and stories written by colleagues who were involved in humanitarian care. Pilgrimages attract large number of 'travelers' and yet we know so little about these pilgrimages. Chapters on the Muslim, Hindu, Buddhist, and Christian pilgrimages aim to correct this.

Diseases also travel. The spread of global diseases and pandemics is fascinating. This book provides an overview of the pandemics, in particular that of cholera, yellow fever, severe acute respiratory syndrome and influenza. Globalization, migration and health lead to a history of disease and disparity in the global village - our world. And what about the revised International Health Regulations - what do we need to know about them in the context of travel medicine?

In the next millennium, our world will have inherited further global movement. It may even include travel to aerospace. The 'Epilogue' awakes some of our old dreams - the last frontier, space travel...

Annelies Wilder-Smith has lived in China, Papua New Guinea, Nepal, New Zealand, and Switzerland. She is currently based in Singapore, from where she continues to travel extensively throughout Asia. She is the Head of the Travellers Health and Vaccination Centre, one of the largest travel clinics in Asia. She was in a unique position to do research on W135 meningococcal disease in Hajj pilgrims during the outbreak. She experienced firsthand the SARS epidemic in Singapore.

Eli Schwartz is the Director of the Center for Geographic Medicine and Tropical Diseases at Sheba Medical Center, Tel-Aviv University, Israel. Eli is a real tropical medicine specialist. He obtained all his experience in the field, including Nepal, Tibet, and numerous adventure travels to Africa, where he prefers to do his studies on the sides of the Omo River.

Marc Shaw is a passionate traveler, doctor, actor and observer of fine humor. His favorite pastime is to be an expedition doctor. This has taken him to exotic places such as Namibia, Mongolia, Pitcairn Islands, and to the Amazon. He is the Director of WORLDWIDE Travellers' Health Centres in New Zealand."

Table of Contents

History of Travel Medicine

History of the Development of Travel Medicine as a New Discipline

Education in Travel Medicine

Education in Travel Medicine; The Gorgas course: Learning Travel Medicine While Traveling; The Ten Commandments for Healthy Tropical Travel

Evolution of Travel Vaccines

Routine Vaccinations and Travel; Recommended Travel Vaccines: From "Travel Vaccines" to Universal Vaccination: The Hepatitis A Story; Required Travel Vaccinations: Yellow Fever - The Disease and the Vaccine; Remote Travel Vaccines: The Undulating Fortunes of Typhoid Vaccines; Dodging the Bullet: Preventing Rabies among International Travelers

Malaria Drugs and Infections of Adventure

Barking Up the Right Trees? Malaria Drugs from Cinchona to Qing Hao; Infections of Adventure and Leisure

Personal Tales: Travel Medicine Practitioners Share Their Stories

Final Log: Amazonas Adventure; Tales from the Mountains; Confessions of a 'Reality TV' Doc; Tomb Raider's Crew Doctor; The Woman Atop the Crocodile: Newton's Law in Africa

Tales Behind the Research in Travel Medicine

The Borneo Eco-Challenge: GeoSentinel and Rapid Global Sharing of Disease Outbreak Information; Understanding Malaria Prophylaxis: Lessons Learnt on the Omo River, Ethiopia; Travelers' Diarrhea: Tales from Mexico; The story of the CIWEC Clinic in Kathmandu, Nepal; History of Cyclospora at the CIWEC Clinic, Nepal; Meningococcal Disease and the Hajj Pilgrimage; Too High Too Fast: Experiences at High Altitude; The Pleasures and Perils of Traveling with Young Children; Mongolian Expedition; Evacuation of Travelers: Personal Anecdotes, Pearls and Conclusions

Traveling for a Cause

Globalization, Migration and Health: The History of Disease and Disparity in the Global Village; Stories of Undocumented Migrants to the USA; Between Crossing Boundaries and Respecting Norms: The Story of Women Labor-Migrants in Israel; Humanitarian Care in Haiti and Rwanda; Muslim Pilgrimage; The Pilgrimages of Christianity; Hindu Pilgrims; Pilgrimages in the High Himalayas

When Diseases Travel

Cholera — A Travel History of the First Modern Pandemic; The Role of Armies in Spreading Epidemics: Vector and Victim; The Spread of Disease in the 20th and Lessons for the 21st Century; A Travel Medicine Practitioner during the SARS Outbreak in Singapore; What Does the Travel Medicine Practitioner Need to Know About the International Health Regulations?

Epilogue

A Look Into the Future- Space Travel

I found the book to be quite variable in the quality of the presentations. Some were quite detailed and demonstrated a great deal of effort, while a few were superficial and seemed to have been hastily composed, without any real attempt to be revealing or comprehensive. For the price ($49.95 U.S.), the amount of entertaining and useful content is reasonable, but not overwhelming. There is not a great deal of structure or organization to this volume. I suspect that the section headings were chosen so that each of the contributions could have a formal placement. The book will appeal most to persons interested in travel medicine. However, one should not be misled by the title, which implies that the stories will necessarily somehow relate directly to a particular scientific theme or concept. As best I can tell, this is a collection of short contributions about topics chosen by the contributing authors. It ranges widely from medical advice to cultural musings, so be prepared to switch gears.

Tags: travel medicine, wilderness medicine, outdoor medicine, healthline

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Mountain Rescue Doctor

The following is a book review I wrote that appeared in the December 2007 issue of Diversion Magazine:

Wilderness medicine is the art and science of practicing medicine in unpredictable and sometimes extremely harsh environments, as found in the mountains at high altitude, at sea during expeditions to remote reefs or under the harsh sun of an equatorial desert. It is not for the faint of heart and requires a willingness to endure isolation, limited resources and physical and emotional hardship. With our culture's appetite for stimulation, and with the media's ability to bring current events into our homes with remarkable speed, stories of rescues in the wild have become prominent in modern life.

Most tales of search, rescue and wilderness medicine begin with an account of how the victims got into trouble. Sometimes they venture into inclement weather without having thought about how to prepare a shelter or what to do if they become injured or lost. Sometimes it's just plain bad luck, as the forces of nature conspire to produce an unanticipated storm or avalanche.

In Mountain Rescue Doctor: Wilderness Medicine in the Extremes of Nature, Christopher Van Tilburg, M.D. offers a collection of tales about mountain rescue in Oregon, where he is a member of the Hood River Crag Rats, reputed to be the oldest mountain rescue team in the United States. As an emergency physician and an expert in many aspects of wilderness medicine, he is well qualified to be part of such a team; as a skilled writer, he engages, informs and entertains the reader.

Van Tilburg's stories are highly personal, each describing the setting and events of an actual rescue. In river parlance, that is the main run - but as anyone knows who has floated the Colorado River within the Grand Canyon, there is much to be learned from the side hikes. Brief literary forays are scattered throughout Mountain Rescue Doctor as Van Tilburg shares his thoughts on what it means to be a physician, how he became an aficionado of wilderness medicine and how he depersonalizes rescue situations. He discusses topics such as injury prevention, rescuer and physician liability, and the risks, rewards, appropriateness and ethics of rescues. One of the questions I am most frequently asked by medical students and residents-in-training is how they can work wilderness medicine into their future as busy clinicians. Now I can suggest this book as an example of how one doctor answered his calling.

It is not a page-turner like Aron Ralston's Between a Rock and a Hard Place or Jon Krakauer's Into Thin Air. There is an element of stream of consciousness to it, which does not detract from its value but illuminates Van Tilburg's approach to life, medicine and his mountain rescue avocation. Mountain Rescue Doctor is a useful addition to the literature of wilderness medicine because it sheds light on one doctor's motivation in devoting a large part of his professional life to this dynamic and essential specialty.

Tags: Mountain Rescue Doctor, wilderness medicine, outdoor medicine, healthline

Labels: Christopher Van Tilburg, Mountain Rescue Doctor

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Thank You to Trick-Cycling for Beginners for Grand Rounds

Thank you to Trick-Cycling for Beginners for including my post about comments related to two victims and a firefighter trapped by a recent San Diego wildfire within this week's edition of Grand Rounds. Grand Rounds is a weekly compilation of posts related to health care compiled by a host, who makes a great effort to compile an interesting collection for readers.

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Comments on "Another Man and a Boy to Admire"

I recently posted about "Another Man and a Boy to Admire." The post related to a tragic story about a young man and his father, who were burned and killed, respectively, by one of the San Diego fires. To understand what follows in today's post, please read the original post, then read the (following) comments that arose in response:

Anonymous said...
"I'm sorry, but someone who ignores a fire fighter's order to heed a previously issued evacuation order and instead drives after the fire truck and gets himself killed and his son seriously injured is no one to admire.

Part of the difficulty in fighting the recent wildfires in San Diego (a small part, but it was significant) were people like this guy who did not evacuate and forced firefighters to move into dangerous areas to try to protect human life instead of working where they were most likely to be able to get the flames under control. They endangered themselves, the firefighters trying to protect us all, and the property of others that burned due to the diversion of firefighting resources."

Anonymous said...
"Oh, and the Varshocks also apparently lied to the firefighters telling them the best place to turn around was their yard (where there was not room to turn around the fire truck) in an attempt to get the firefighters to come to their house (where three firefighters and the 15 year old were badly burned and elder Varshock died)."

Anonymous said...
"I just ran across these comments on the Internet, and I feel sorry for the family to be so maligned by other's anonymous comments. I know this family well - unless you are sure of what you are saying, please don't make assumptions about what happened. Very few people do know the circumstances. You cannot believe everything you read in the paper. The family lived out there, fighting many fires for many years! This fire was different."

Paul Auerbach, M.D. said...
"This is an important series of comments, because the point is raised about personal responsibility, and how we react emotionally to situations in which there are often different ways to view the same situation. I'm going to elevate this discussion to a post."

And now, this is that post. The comments above evoke dialogue that raises a number of issues, not the least of which relates to the emotions generated by a tale of extremely unfortunate circumstances. I have to deal with these sorts of emotion often as a physician in the emergency department, where persons present with illnesses and injuries that are caused by a mixture of events, natural history, genetics, bad luck, and/or poor judgment. It's not uncommon to come away from a patient feeling that their actions in part or entirely led to their misfortune. But when that happens, I make my best effort to not become judgmental, because I can easily recall making bad decisions, and either living with the consequences or being lucky to have not been trapped by the error of my ways.

Behavior, risk, and liability are frequent topics of discussion in wilderness medicine. Beyond the issues of risk and fault, there are considerations of response. Rescues put the rescuers at risk. It is not trivial to have to jump into heavy seas, maneuver a helicopter at high altitude in poor visibility and high winds, or race into a burning forest to extract a victim surrounded by flames. It can become very difficult emotionally if the person at the bottom of the ravine wasn't wearing a safety harness, if the man overboard neglected to wear his lifejacket, or if the comatose human dangling from a rock face didn't feel his helmet was necessary.

But who among us is perfect? We all make mistakes, and sometimes they are costly for us and for the people who consider it their duty to bail us out. If I refused to help all of the persons who had a hand in creating or worsening their illnesses, I wouldn't be assisting half the people who need me. Should I let nature take its course when an intoxicated college student handles a rattlesnake and is bitten on the hand? Should I turn off the oxygen when I discover that the man burned in an explosion was intoxicated when he attempted to light his camp stove? Should I walk away from the woman who ignored the "stay out" sign and plunged into a scalding thermal pool? Of course not. I may not always be happy about it, but my duty (and calling) is to attempt to rescue, attempt to save, and attempt to heal.

The first set of comments from "Anonymous" misinterpret why I chose to admire the boy who was burned, and the firefighter who was involved in a rescue. Whether or not the burn victim didn't evacuate properly is not why I decided to hold him in admiration. I decided to do that because of the way he was portrayed by those who know him, and because of his spirit after he was injured. For the foreseeable future, life will not be easy for him, and he will benefit from support. As far as the firefighter goes, selfless behavior such as his gets my vote every time. Volunteer or paid, persons who put their lives on the line to help others are true heroes.

But there is a very reasonable point made by "Anonymous," if I understand his criticism correctly. If indeed a person decides to ignore a danger warning and puts himself and others at risk, that kind of decision may be more than foolhardy - it can be cruel and unfair. The fact of the matter is that professional rescuers, good Samaritans, and anyone who considers it his or her duty to rescue first and ask questions later is vulnerable to responding to what might be a situation that could have been avoided. We carry responsibility for most of our actions. Human nature being what it is, some of our decisions will be judged selfish or incorrect. Some of these decisions will get us into the kind of trouble that requires assistance. All I can say about that is that for persons in any kind of service business, it comes with the territory. That doesn't make it right - it just is what it is. Hence, education and injury prevention programs are incredibly important.

I don't know how to respond to the second comment from "Anonymous," in which he essentially says that a conscious effort was made to dupe the firefighters for the purpose of having them focus on a particular rescue. I would like to think that this was not the intent of the victims, and that the firefighters were sufficiently well trained to make the best decisions available to them at the time. But I was not there, so can only comment (like most people) on what is reported to me.

The process here is good. Readers should feel free to (respectfully) speak their mind, and we should be willing to talk through the difficult issues. The bottom line is that this blog exists to provide useful information, and your comments should be intended to enhance that effort.

My take away from all of this is that every action has a consequence, even if it is not readily apparent. It is suspected that arson may have played a role in one or more of the San Diego fires. That is heinous and will result in punishment for any identified perpetrators. People who did not evacuate by choice made decisions to accept the risks in exchange for what might have been gained by remaining in the path of the fire. To the extent that remaining in harm's way was responsible for putting others in jeopardy, the responsibility for adverse events is fairly shared. But that fact does not make me have any less compassion for the victims, and it doesn't diminish the bravery and heroism demonstrated by many during and after the fires.

Tags: wildfire, fire, Richard Varshock, Andrew Pikop, wilderness medicine, outdoor medicine, healthline

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Twinject Update

The Twinject auto-injector is designed to deliver two doses of aqueous epinephrine, USP 1:1000, and comes available for injections of 0.15 mg (each dose) or 0.30 mg (each dose). The product has been redesigned to make it easier for use. The first dose is a true autoinjection, in that the user removes the green caps at either end of the device, holds the red rounded tip against the middle of the outer thigh, then presses the pen-shaped device firmly ("hard") against the skin, which fires the auto-injector to thrust a needle through the skin. By the count of 10 (slowly), the drug is administered. If a second dose is needed (for instance, if a person is suffering a severe allergic reaction and symptoms are not improving or are worsening after 10-15 minutes), the rounded red cap is unscrewed from the device, which exposes a needle attached to a small syringe, the combination of which sits inside the barrel of the device. The needle-syringe combination is easily removed from the barrel, a small yellow collar then removed from the plunger on the syringe, and then the needle-syringe can be used to inject the second dose of epinephrine into the patient by inserting the needle and pushing the plunger all the way down.

Verus Pharmaceuticals, Inc. of San Diego, CA distributes the Twinject autoinjector, as well as an instructional DVD in both English and Spanish that also includes information on understanding and treating anaphylaxis (severe allergic reaction). A carrying case for the enhanced Twinject is available (pictured below).


Tags: Twinject, epinephrine,allergic reaction, wilderness medicine, outdoor medicine, healthline

Labels: allergic reaction, allergy, autoinjector, epinephrine, Twinject

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Thank You to Dr. George for Grand Rounds

Thank you to Dr. G.C. George, posting at Odysseys of George, for including my post about the International Journal of Wilderness within this week's edition of Grand Rounds. Grand Rounds is a weekly compilation of posts related to health care compiled by a host, who makes a great effort to compile an interesting collection for readers. Dr. George is an accomplished underwater photographer, and his beautiful images grace this week's Grand Rounds.

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International Journal of Wilderness

Persons interested in outdoor medicine are often very much interested in the wilderness, so let me take this opportunity to make you aware of the International Journal of Wilderness, which is published by the WILD Foundation of Boulder, Colorado, USA. The Editor-in-Chief is John C. Hendee, Professor Emeritus of the University of Idaho Wilderness Research Center.

The stated mission of the journal is to link wilderness professionals, scientists, educators, environmentalists, and interested citizens worldwide with a forum for reporting and discussing wilderness ideas and events; inspirational ideas; planning, management, and allocation strategies; education; and research and policy aspects of wilderness stewardship. The journal is published three times a year.

The August 2007 issue is indicative of the depth and breadth of the content. I was particularly drawn to an article entitled "Wilderness and the Human Soul," contributed by Ian Player of South Africa. This extraordinary man founded the multi-racial Wilderness Leadership School during the apartheid era, which will celebrate its 50th anniversary this year. In his remarks, Mr. Player points out the spiritual nature of wilderness, and its importance for the emotional fabric of a country, indeed, for civilization: "This is our task in the 21st century. We need something that will stir our psychic depths and touch the images of the soul. It has to surpass creeds and instantly be recognized. We must learn a new language to convey the feelings of beauty, hope, inspiration, and sacredness for humanity and all other life. We need to remember the first principle of ecology: that 'everything is connected to everything else,' and the wilderness experience is the spiritual spark that ignites the understanding."

Subscription inquiries for the journal can be directed to WILD Foundation, P.O. Box 1380, Ojai, CA 93024, USA. Telephone: (315) 640-0390. Fax: (805) 640-0230. E-mail: info@wild.org

Tags: International Journal of Wilderness, wilderness, WILD Foundation, wilderness medicine, outdoor medicine, healthline

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Mountain & Wilderness Medicine World Congress Abstracts Part 5

As I noted in my first post about the Mountain & Wilderness Medicine World Congress, sponsored by the Wilderness Medical Society and the International Society for Mountain Medicine in Aviemore, Scotland from October 3-7, 2008, there were many excellent abstracts presented. The following is the fifth and final installment of some of the more interesting of these:

Jeremy Windsor, Edwin Hamilton, Michael Grocott, and James Milledge of London, United Kingdom described a field trail of a new avalanche survival device, which they call the Snow Snorkel, in an abstract entitled, “Trial of the Snow Snorkel: A Proof of Concept Study.” Subjects were buried in snow at least 30 cm ( inches) deep and breathed through the device for 60 minutes. The apparatus essentially consists of a tube that allows the victim to inhale through his mouth and nose, and exhale directly into the tube, which dumps the expired air (which contains more carbon dioxide and less oxygen that the inspired air) near the subject’s waist. The results were quite encouraging, in that eight subjects using the device were able to tolerate 60 minutes under the snow. After the 60 minutes was elapsed, the subjects were instructed to breath without utilizing the device for up to an additional 15 minutes. Three made it through that period, while the other four terminated the trial at 11, 10, 6, 6, and 4 minutes. These observations suggest that this device can be further refined to be affordable and useful for persons at avalanche risk.

Wang Xiaoqing and Chen Qiuhong of Xining, China presented an abstract entitled, “Physiological Adaptation to Hypoxia in Indigenous Animals,” in which they considered the reasons why certain indigenous mountain animals, such as the yak and Tibetan antelope, have adapted to high altitude. In support of some of the theories of the pathophysiology of high altitude illness in humans, they found lower pulmonary vascular tone and augmented endogenous nitric oxide production in the adapted (e.g., tolerant to high altitude) animals, as well as a modified response in the oxygen-carrying affinity of the blood. If these animal data can be extrapolated to humans, then it will add impetus to lowering pulmonary artery pressure to prevent and treat high altitude pulmonary edma, and perhaps even provide a new animal model(s) for high altitude medicine.

Most of the abstracts from the meeting are available in the journal Wilderness & Environmental Medicine, Volume 18, Number 3, 2007.

Tags: Wilderness Medical Society, WMS, International Society for Mountain Medicine, mountain medicine, Aviemore, World Congress, wilderness medicine, outdoor medicine, healthline

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Thank You to Enoch Choi, M.D. for Grand Rounds

Thank you to Enoch Choi, M.D., posting at Medtalk: Dr. Geek, M.D. as a contributor to the Medhelp site, for including my post about vitreous detachment within this week's edition of Grand Rounds. Grand Rounds is a weekly compilation of posts related to health care compiled by a host, who makes a great effort to compile an interesting collection for readers. I also very much appreciate the mention of a guest post at "Medicine for the Outdoors" about a method to treat shoulder dislocation, contributed by Jeremy Joslin, M.D.

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Floaters and Flashing Lights

Medicine for the outdoors is just that – application of the healing arts in outdoor environments, where one must on occasion make do with limited diagnostic capabilities (compared to what is available in a hospital or clinic) and supplies. Often, one must make an educated guess about what might be going on with a victim, medically speaking. Without an x-ray or stethoscope, it may be difficult to confirm the presence or absence of fluid in the lungs or collapse of lung tissue. Without an ophthalmoscope or slit lamp, it is impossible to peer within the eyeballs to determine whether or not there is a problem with the lens, vitreous, or retina. Without a meter to measure the quantity of glucose in the blood, one must rely upon clinical judgment and evaluation of symptoms to estimate whether or not a person is suffering a hypoglycemic episode.

I recently suffered a new (for me) medical problem, as the vision in my right eye was suddenly and painlessly obscured by a tangle of what appeared to be threads and black dots. From my medical training, I knew that these were “floaters,” and was concerned that they might represent a tear in my retina. Fortunately, I was close to the expert care of a skilled eye doctor. At this point, my retina is intact, but I need to be very careful with my activities over the next few weeks until the process of vitreous separation, which I will describe below, subsides.

After I knew for sure what had happened, I thought, what if this had occurred during my recent visit to Mt. Everest base camp, away from sophisticated medical care? What if it happened to someone on a backcountry ski adventure, when exploring in the jungle, or at sea on a diving expedition? If any of these was the case, he or she would have to make due as best possible, worried about what might be wrong and, in the absence of someone trained and properly equipped to complete a full eye exam, unable to truly confirm a diagnosis.

Indeed, this is how most of the world lives. Most people don’t have rapid access to medical professionals, like we do. Furthermore, what I am suffering is actually quite common, and occurs with regularity to persons unable to obtain prompt evaluation. These people must make decisions – do they wait it out and hope for the best, or do they end their travels in order to play it safe and seek an evaluation? This might require expensive and potentially hazardous modes of transportation, which adds yet another layer of risk to the decision making process.

So, using information from an excellent set of patient education instructions provided to me by my ophthalmologist at the Palo Alto Medical Foundation, let’s consider “floaters and flashing lights,” and put it all in the context of what one might do and consider if faced with this problem in an outdoor, remote from medical care, setting.

Floaters are small spots, lines, clouds, cobwebs or veils that move around in your field of vision, especially when you move your eyes. They can be in one or both eyes, but usually show up in one eye at a time. As I can certainly attest, they are easiest to see when you look at the sky or against a plain white background. Floaters are caused by tiny opacities inside the vitreous, which is the gel that fills the inside of the eyes. In childhood and adolescence, the vitreous gel is clear, so that floaters are not seen. In adulthood, floaters can develop when the vitreous gel forms small clumps as part of the aging process. As light passes from the outside of the eye, through the cornea and lens, and then through the vitreous gel before it strikes the retina to record an image, the floaters can cast shadows on the retina. Floaters are annoying, but not dangerous, particularly if they have been present for a long time.

However, the sudden appearance of floaters can signify separation of the vitreous gel from the retina. This occurs because the vitreous gel shrinks as it ages. If it shrinks enough, it begins to peel away from the retina, in what is called a vitreous separation or detachment. It is more common in nearsighted people and in persons who have had cataract surgery or injuries to their eyes or head. When a vitreous separation occurs, the floaters appear suddenly. As the gel peels away from the retina, it tugs on it, which can cause a person to appreciate flashes of light, usually on the outer (ear) side of the eye. These usually last no more than a second, and are caused by the nerves within the retina (which connect to the large optic nerve) being stimulated mechanically by the tug of the vitreous gel. Flashes are difficult to appreciate in daylight, but can be easily seen in the darkness. Moving the head or eyes can cause the flashes. Since flashes mean that the vitreous is pulling on the retina, this is a warning sign, because the traction can cause a retinal tear. If this happens, then an ophthalmologist needs to perform laser surgery as soon as possible in order to prevent a full-blown retinal detachment.

The normal course for a vitreous separation is a 2 to 4 week process in which the separation is completed. This may be punctuated by intermittent addition of new floaters, but usually the burst of opacities is at the beginning of the process. Over time, most of the floaters diminish or disappear, but there may be some residual floaters. During the course of the separation, when a person first notices the floaters, and if a person suddenly develops new floaters, more frequent flashing lights, or a defect in a field of vision (often described as a "dark curtain"), then an ophthalmologist should perform an examination to be certain that there is not a retinal tear or detachment. It is important to avoid sudden eye or head movements for several weeks after the onset of a vitreous separation, in order to decrease the likelihood of developing a retinal tear or detachment.

What does a person do if faced with this situation when distant from the care of an ophthalmologist? The major risk is retinal tear(s) or detachment. If a new vitreous detachment is suspected, then it is wise to begin to head toward civilization in order to undergo a proper examination. However, if it is likely that a retinal detachment has occurred (e.g., there is a "field cut," or a darkened area of vision as if a curtain was being pulled across the field of vision from any direction), then it is prudent to evacuate immediately, including a more expensive mode of transportation if necessary, because treatment for retinal detachment is usually an operation by an opthalmologist, and time is of the essence. A progressive retinal detachment can lead to permanent loss of vision in the affected eye.

In terms of exercise, it is wise to avoid sudden head or eye movements, so no jogging or swimming with rapid head movements, wrestling, significant straining, etc. Until the vitreous separation process is complete, a person should try to turn the head to look in a direction, rather than hold the head in a fixed position and move the eyes. All of this may be difficult in a precarious situation, such as rock climbing or kayaking, but you should just do the best you can given your particular circumstances.

photo courtesy of www.maculacenter.com

Tags: vitreous separation, retinal tear, floaters, wilderness medicine, outdoor medicine, healthline

Labels: eye, eye injury, floaters, retina, retinal detachment, vitreous, vitreous detachment

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