Race safety

More on Swimming Induced Pulmonary Edema (SIPE)

September 12, 2012 By Larry Creswell, MD 3 Comments

In the aftermath of several recent triathlon fatalities, I’ve been a part of several conversations about swimming-induced pulmonary edema (SIPE). These conversations all got started with somebody asking the question: could these recent deaths be due to SIPE? I truthfully don’t know the answer.

I recently wrote a blog post where I introduced the topic of SIPE. I discussed a liitle bit about the physiology, provided some information from the scientific literature, and shared personal stories from a couple affected triathletes. You might start with reading that post and then continue reading here.

Today, I thought I’d draw your attention to some additional sources of information about SIPE.

A Book

In my opinion, the most useful narrative about SIPE in layman’s terms is in a recent book by Ingrid Loos Miller, entitled Fearless Swimming for Triathletes. Ingrid has long had an interest in triathlon swim safety. She’s a USAT certified coach and a member of the United States Lifesaving Association. The book is good reading for any triathlete. In Appendix C, though, Charles “Trey” Miller writes on the subject of SIPE. For those who don’t know Trey, he is a PhD epidemiologist and Chair of the Department of Biomedical Sciences, Associate Dean for Research, and Associate Dean for the Graduate School of Biomedical Sciences at the Texas Tech School of Medicine. He is a triathlete with personal experience with SIPE and has authored one of the very few scientific reports on triathletes and SIPE–which I mentioned in my first blog piece about SIPE. His section of Ingrid’s book very clearly explains what is known about SIPE in language that makes the topic accessible.

Some Articles in the Non-Medical Press

One article that’s received some attention is by Rudy Dressendorfer, Ph.D., who wrote an editorial in the Sports Medicine Bulletin published by the American College of Sports Medicine. I mentioned this article briefly in my earlier post. The discussion about SIPE physiology is worthwhile. He speculates about how SIPE might affect triathletes and offers some suggestions for affected athletes. I’d caution that his recipe for prevention may not be broadly applicable; it seems from athlete reports that successful prevention strategies might be very individualized and not always broadly applicable or successful.

Kat Calder-Becker and Trey Miller wrote a niece article for Slowtwitch in 2007 in which they describe the general features of SIPE and share personal experience with the condition. They conclude the article by writing that “more research is needed.” That’s certainly true.

Online Forum Discussions

There have been recent threads about SIPE at a variety of online forums, including Slowtwitch, dctriclub, U.S. Masters Swimming, Beginner Triathlete, and IAmTri, among others. You can search for SIPE at the forums to find the pertinent discussions. Oftentimes, the information shared about SIPE is factually incorrect, but the valuable portions are from athletes who share stories related to breathing difficulties during races. Our fellow triathletes and open water swimmers should learn from these stories that breathing difficulties during a race indicate an emergency.

I’ll draw your attention to 2 recent threads at Slowtwich that deserve special mention. In the first, simply entitled Swimming Induced Pulmonary Edema, a triathlete identified as KAP shares her story of breathing difficulties during an Olympic distance triathlon. She was eventually treated at the Johns Hopkins Hospital, where the suspicion of SIPE as a diagnosis was confirmed with x-rays. Her story is good reading. It should serve as additional warning to athletes who experience breathing difficulties during a race.

The second thread worth mentioning is entitled SIPEsters: please stop spreading misinformation. The valuable portion here is the exchange at the end between me and Trey Miller. Athletes should read Trey’s response to the question: Given what we know about SIPE, what should athletes, event organizers, and USAT do? His suggestions are thoughtful.

From the Medical Literature

Virtually the entire medical literature on the clinical aspects of SIPE has its origins in the experiences of scuba divers or military divers. A small number of deaths attributable to SIPE have been reported in that setting. Some of the reported accounts have dealt with cases of SIPE that has developed in surface swimmers, though. One important feature of the various reports is that recovery from an episode of SIPE appears to be complete, most often with just supportive care–that is, the condition resolves with cessation of exercise and removal from the water. One article documents that typical parameters of lung function normalize after SIPE episodes:

1. Ludwig BB, et al. Cardiopulmonary function after recovery from swimming-induced pulmonary edema. Clin J Sport Med 2006;16:348-351.

I’m aware of only 2 articles in the medical literature that deal with SIPE specifically in triathletes:

2. Miller CC et al. Swimming-induced pulmonary edema in triathletes. Am J Emerg Med 2010;28:941-946.

3. Carter EA and Koehle MS. Immersion pulmonary edema in female triathletes. Pulm Med 2011;1-4.

I summarized the important information from the first article in my previous blog post. Again, this article reports on a survey of triathletes regarding their symptoms that might be suggestive of SIPE. The second article reports on 3 cases of female triathletes, ages 43 to 59, who were diagnosed with having SIPE. In 2 of these athletes the symptoms developed during training swims. In the 3rd athlete, there were 2 documented episodes of SIPE during triathlon race swims. In all 3 cases, the diagnosis of SIPE was supported by chest x-ray evidence of pulmonary edema without other explanation.

I understand from my reading that establishing SIPE as a cause of death at autopsy is difficult because pulmonary edema is a common finding in drowning victims. Some of the forensic challenges in this setting are summarized in an article:

4. Papadodima SA, et al. Forensic investigation of submersion deaths. Int J Clin Pract 2010;64:75-83.

Warnings from Event Organizers and Athlete Organizations

With a growing recognition that SIPE can affect recreational athletes during open water swim competitions, it’s not surprising that we’d begin to see warnings to athletes about this possibility. As an example, there is an annual Horsetooth Open Water Swim (with various events up to 10K distance) held in Ft. Collins, Colorado. I noticed that their website information about athlete safety now includes a warning about the possibility of SIPE, pointing out that breathing difficulties during the swim constitute a medical emergency and that athletes with these symptoms should stop immediately and seek assistance. As another example, I saw that the U.S. Open Water Swimming Connection sent an email to its membership that addressed the issue of SIPE and included an athlete account of an episode during a 40K swim.

A Couple Notable Athlete Accounts

I came across an account from an triathlete, Andrea Himmel, who competed at the recent Ironman New York triathlon. His account is chronicled in a post at www.policymic.com and has been shared or reprinted in several other online venues as well. His story is worth reading. His troubles with breathing started during the swim portion of the race and continued during the bike portion, where he had to drop out at about the halfway point. Although he didn’t immediately seek medical attention outside the race venue, he suspects that his symptoms were due to SIPE. His account seems to be similar to those shared by other triathletes at the various Forums that I mentioned above.

I would take issue with Andrea’s speculation about the cause of death for Andrew Naylor, another athlete who competed in the race. Yes, Mr. Naylor died during the swim portion of the race. I’m not sure who Andrea was referring to in the article when he mentioned, “now we hear from people involved in the Ironman medical circles that the man who died after the swim likely died from SIPE.” I certainly don’t know what caused Mr. Naylor’s death, but I’ve spoken with the medical director for the race and learned that his cause of death has not yet been determined. I’m equally certain, though, that when all of the relevant testing is completed that we’ll hear from the medical examiner about the autopsy findings and conclusions that can be drawn about the cause of death.

Another recent account comes from a triathlete who competed in my hometown race, the Heatwave Classic Triathlon in June. This athlete shared his story at Slowtwitch and I’ve since had a chance to speak with him about his experience on race day. As you’ll read, this is an accomplished open water swimmer who had a very uncharacteristic problem with breathing during the 1/2-mile swim at the event. He was unable to continue the race after completing the swim, received medical attention at the race venue, but did not immediately go to the hospital for further evaluation. He shares his story with subsequent evaluation that led to a diagnosis of exercise-induced asthma. I bring this athlete’s story to your attention simply to point out that there are many possible explanations for new breathing difficulties. In my view, breathing problems should be evaluated carefuly to determine a cause.

My Thoughts and Observations

1. Triathletes and open water swimmers should be aware of SIPE and the possibility that this condition can be lethal.

2. Symptoms of SIPE can manifest for the first time even in experienced swimmers. Symptoms may develop rapidly, be unexpected, and confuse the athlete about the cause.

3. The development of SIPE does not appear to be confined to cold water swims or only to victims who are wearing a wetsuit at the time.

4. SIPE appears to be self-limiting–that is, the symptoms will subside if the victim stops exercising and gets out of the water.

5. Because of #2, #3, and #4, athletes who experience breathing difficulties in the open water should treat the problem like a medical emergency and STOP swimming and SEEK immediate assistance. Because of the challenges of rescue in the open water, your life could depend on recognizing a problem early and getting out of the water. I would encourage affected athletes to get complete medical evaluation as soon as possible after an episode.

6. There appear to be no effects on lung function after an episode of SIPE, but repeat episodes of SIPE may occur.

7. Affected athletes have described a variety of strategies for preventing repeat episodes of SIPE. From athlete accounts, no single strategy appears to be universally successful.

8. Affected athletes should use EXTREME CAUTION in subsequent open water training and races, being hypervigilant for warning signs.

9. Event organizers and on-water rescue personnel should be familiar with SIPE. The safety plan should allow for athletes with breathing difficulties to be removed from the water as quickly as possible.

Pulmonary Embolism Kills Triathlete

August 28, 2012 By Larry Creswell, MD Leave a Comment

A news report about the Ironman Philippines 70.3 triathlon race last week caught my attention. A relay participant, Ramon Igana, Jr., 44 years old, died during the bike portion of the event and autopsy findings suggested that acute pulmonary embolism was the cause.

Reporting on the event does not make mention of previous medical problems, but the victim’s wife, a physician, reported that Igana felt well on the morning of the race. Witnesses reported that Igana was seen wobbling on the bike and appeared pale shortly before he suddenly fell to the ground. I can’t find mention of the resuscitation efforts on the scene, but he was taken to a nearby hospital where he was pronounced dead on arrival.

Let’s quickly review the medical issue of pulmonary embolism. This is a condition in which blood clots form somewhere in the body’s venous system (deep venous thrombosis, or DVT), become dislodged, and are carried with the bloodflow to the right side of the heart. From there, the blood and blood clots are pumped to the pulmonary arteries which carry blood flow to the lungs. The blood clot(s) become lodged in the branches of the pulmonary arteries, impairing proper blood flow to the lungs. This process is called thromboembolism. And when it occurs suddenly, we call the problem acute pulmonary embolism.

Pulmonary embolism produces several symptoms, depending upon the severity, or amount of blood clot that becomes deposited in the lungs. Shortness of breath, increased heart rate, and chest pain or discomfort are common symptoms. In serious cases, there can be almost complete obstruction to blood flow in the lungs, and this can lead to fatal cardiac arrest. The diagnosis is usually established by chest CT scan and the conventional treatment is with blood thinning medications (eg, heparin, Coumadin) to prevent additional blood clots from forming.

But interestingly, although pulmonary embolism is responsible for as many as 200,000 deaths per year in the United States, this is a very uncommon problem for athletes. We know that the risk factors for the development of DVT, the precursor for pulmonary embolism, include immobilization, a diagnosis of cancer, or previous history of DVT–and all of these would be relatively uncommon among active athletes. But it can occur. Professional tennis player, Serena Williams, is the most recent high-profile athlete to be affected by pulmonary embolism and her story has been shared widely in the popular press.

I’ve shared previously here at the blog that I’ve been a part of a medical panel at USA Triathlon that’s reviewed event-related fatalities over the past decade. I can share that pulmonary embolism was not identified as a cause of death in any of the 45 victims. I’m also not aware of any other reporting on triathlon race-related fatalities due to pulmonary embolism. And that’s why the report from the Philippines caught my attention.

Sports-related sudden cardiac arrest (SCA) has received increasing attention because of the increasing popularity of recreational sporting activities worldwide. Pulmonary embolism is an uncommon cause of sports-related SCA, occurring in approximately 0-2% of victims, depending upon the popoulation studied.

A quick search of the medical literature shows just a single case report of non-fatal pulmonary embolism in a triathlete. This was a 33 year old woman who completed a half Ironman triathlon and developed lower extremity swelling and pain 3 weeks later. These symptoms were followed by the abrupt onset of increasing shortness of breath and light-headedness. In retrospect, her caregivers speculated that a 3-week period of rest following her triathlon event resulted in relative immobility that was the “set-up” for the development of DVT.

DVT is the precursor for pulmonary embolism and usually occurs in the lower extremities. In some athletes, the veins of the upper extremity can be affected in a condition known as effort thrombosis. The typical symptoms are swelling, tenderness, and pain in the affected extremity. Athletes should be vigilant for such symptoms and seek treatment for DVT in order to prevent pulmonary embolism.

Open Water Swim Safety: Fran Crippen and Recommendations from USA Swimming

August 16, 2012 By Larry Creswell, MD 1 Comment

The death of 2 athletes during the swim portion of triathlon races this past weekend–1 in New York, the other in Idaho–has renewed discussions in the triathlon community about race safety.

I’ve mentioned here previously that USA Triathlon is in the midst of thoughtful review of race-related fatalities over the past decade and will soon be releasing a report with recommendations. Preliminary information was shared with attendees of the USAT annual Race Directors Symposium this past January in Colorado Springs. From 2003 through 2011 there were 31 swim-related deaths that involved more than 3,000,000 participants.

USA Swimming, the national governing body for swimming in the United States, was confronted with a similar challenge in 2010. Long-distance American swimmer, Francis (Fran) Crippen died during a 10K open water swim race in Fujairah, United Arab Emerites, prompting a review of safety protocols not only by USA Swimming but also by FINA, the international governing body for swimming. The reporting on Crippen’s cause of death has been incomplete, but a report issued by FINA suggested the possibility of a heart abnormality as well as hyperthermia as playing a role.

As we work through the issues of triathlon race safety, it’s worth considering the recommendations that followed from the Open Water Review Commission convened by USA Swimming. I’ll refer you to the original report for all of the details, but 8 points deserve mention and comment (in italics) here:

1. In the letter accompanying the recommendations, the Chair of the Commission wrote, “It goes almost without saying that there must be immediate recognition when a swimmer is struggling or loses consciousness; there must be immediate rescue when loss of consciousness occurs; and there must be immediate resuscitation to address medical emergencies.” This is the important triad of response that is essential if victims of cardiac arrest are to survive.

2. The Commission recommends that the safety plan allow for on-water safety personnel to react to a need for assistance within 10 seconds and be able to reach a disabled swimmer within an additional 20 seconds. This, too, is essential given the fact that the survival rate for sudden cardiac arrest drops precipitiously with the passing of each minute.

3. A ratio of 1 safety craft per 20 swimmers is required. By comparison, USAT requires 1 rescuer per 50 swimmers.

4. A safety communications plan is required. At a miminum, the plan must provide for water-to-water, water-to-land, and land-to-water communications. Furthermore, personnel on all boats and safety craft must have the ability to communicate with the safety officer and the safety officer must be able to communicate with first responders, safety personnel, and officials on the course. All of this is critical to ensure a coordinated response by rescuers. This becomes increasingly important if a swim course design carries swimmers far from shore.

5. An evacuation plan must be part of the safety planning.

6. All athletes must attend a technical meeting before the race where water conditions, safety plan, emergency situations, the safety communications plan, evacuation plan, and safety craft are described. Moreover, athletes must attend a pre-race safety briefing immediately before the race. What’s important is that athletes aren’t allowed to compete if they do not attend the meetings.

7. Temperature. No race can be held if the water temperature is below 16C (60.8F); if the sum of air plus water temperature (in Celsius) is 63. Further refinement of temperature guidelines are in the offing at FINA and USAT should consider any forthcoming recommendations carefully.30>

8. USA Swimming requires athletes to attest annually that they are medically fit and adequately prepared for the races entered. The value of pre-participation screening for medical problems, especially heart problems, cannot be overemphasized.

Marathon Safety

August 15, 2012 By Larry Creswell, MD 1 Comment

With the unfortunate deaths over this past weekend at two triathlons, I’ve had several conversations with athletes about the general issue of sports-related sudden cardiac death (SCD).

I’ve written previously about the rate of SCA at long-distance running events. We learned from a careful study (of nearly 11 million runners) reported earlier this year [1] that the rate of SCA is approximately 1 per 100,000 marathon participants and approximately 1 per 300,000 half marathon participants. The mean age of victims was 42 years and 86% were men. For the non-surviving victims in whom autopsy information was available, the vast majority had an underlying heart condition such as hypertrophic cardiomyopathy (HCM), other abnormal hypertrophy, heart valve disease, or coronary artery disease.

Interestingly, the occurrences of SCA were not distributed uniformly along the length of the race. In marathons, the SCA events were much more common in the 20 mile-to-finish segment. Similarly, in half marathons, the SCA events were much more common in the 10 mile-to-fiinish segment. One reasonable hypothesis is that the SCA events in the final miles of the races may be linked to an increase in adrenaline levels as runners lift the pace or surge toward the finish line.

Today, I thought I’d share some recommendations from the International Marathon Medical Director’s Association (IMMDA) that were approved in March, 2010 and address the issue of how athlete’s can best prepare and execute a long-distance running race with an eye toward preventing SCA. You can review the original report to review the rationale, but I’ll summarize the important recommendations here:

1. Participants should be well-trained and have a race plan that matches their level of training and fitness.

2. Have a yearly physical examination being sure to discuss your exercise plans, goals, and intensity at that visit.

3. Consume a baby aspirin (81 mg) on the morning of the race if there is no contraindication to do so. I’d recommend discussing this with your doctor beforehand.

4. Consume less than 200 mg of caffeine before/during a 10K or longer race.

5. Only drink sports drink (or equivalent) in races of 10K+.

6. Drink for thirst.

7. Do not consume NSAIDS (eg, Motrin, ibuprofen) during a race of 10K+.

8. Consume salt (if no medical contraindication) during a 10K+ race.

9. During the last mile, maintain your pace or slow down; do not sprint the last part of the race unless you have practices this in your training.

These are very thoughtful recommendations. The chances of any single athlete suffering race-related sudden cardiac death is small, but athletes should do the reasonable things to help prevent this type of tragedy.

[1] Kim JH, et al. Cardiac arrest during long-distance running races. NEJM 2012;366:130-140.