1. Sickle Cell Trait in Athletes
James Moriarity MD.
University of Notre Dame

3. Sickle Cell Trait: What is it?
Sickle Cell trait is a condition of the red blood cell that affects the molecule hemoglobin.
Sickle cell trait is the inheritance of one gene for sickle hemoglobin and one for normal hemoglobin.

6. What is hemoglobin?
A molecule inside the red blood cell that carries oxygen

7. Hemoglobinopathies (abnormal hemoglobins)
Three types
Sickle Cell Disease (2 genes for abnormal hemoglobin)
S hemoglobin (lysine for glutamic acid)
C hemoglobin (valine for glutamic acid)
Sickle Cell Trait (1 gene for abnormal hemoglobin)
Thalassemias
Alpha
Beta

8. Sickle Cell Hemoglobin: 1 amino acid change in the 146 amino acids that make up HgB
Valine for glutamine

9. Role of Oxygen
When the red blood cell has oxygen attached, sickle HgB functions normally.
When the red blood cell gives up its oxygen to muscle, the HgB deforms and the HgB molecules stick to one another in a line

16. Sickle Cell is not a disease of race: it is a disease of inheritance, that can affect any race

17. What is the spectrum of sickle cell disease?
malaria and sickle cell

18. Genetics

19. 13 Sickling Deaths, College Football
- 1974, Colorado, ran ~ 800 m
- 1985, Arkansas, ran ¾ mile
- 1986, Mississippi, ran 1 mile
- 1987, Indiana, ran 1200 m
- 1989, Utah, ran ¾ mile
- 1990, New Mexico, ran 800 m
- 1992, Georgia, ran ~ 1000 m
- 1995, Arizona, ran 900 m
- 2000, Tennessee, ran ~ 800 m
- 2001, Florida, 63-min. mat drill
- 2004, Ohio, ran for 10 minutes
- 2005, Missouri, 1-hour field drill
- 2006, Texas, 16 sprints, 100-yd each

20. Aaron O’Neal Summer voluntary workouts Collapsed 1 hour into workout
Cardiac Arrest in the Training Room
Initial cause of death: Viral Meningitis
1:35

21. 1:57

22. 2:22

23. 2:26

24. 2:34

25. 2:39

26. 2:41

27. 2:43

28. DeVaughn Darling Florida State Running Mat Drills
Collapsed at end of drills
Stated to die from cardiac arrythmia
Twin Brother, Devard

29. And the lawsuit followed…
FSU, Family Agree On $2 Million Settlement  
TALLAHASSEE, Fla. (AP) - A judge approved a $2 million settlement Monday between Florida State and the family of Devaughn Darling, a football player who died during an offseason workout in 2001.
The school also will place a memorial to Darling in its athletic department, provide duplicates of photographs and video of his playing time to the family, make replicas of the rings awarded to Darling for the January 2001 Orange Bowl and the 2000 Atlantic Coast Conference title, and maintain a scholarship endowment in the player's memory.
Darling's family members, including parents Dennis Darling and Wendy Smith, sued the school in October 2002, claiming their son died despite complaining of dizziness and chest pains during a workout.
The suit claimed Darling was deprived of water and other fluids during conditioning drills.
It also said the school failed to provide sufficient rest periods during the workouts, did not have adequate medical personnel or equipment available, and failed to recognize that the athlete was in distress.
Darling and his twin brother Devard learned they had a blood disorder, known as a sickle cell trait, after a pre-football physical before their freshman year at Florida State. The medical examiner said the disorder may have contributed to Darling's death, although no definite medical cause was cited.

30. Why do athletes with sickle cell trait die?
During highly intense workouts, oxygen levels in the muscle fall and acid in the muscle rises
In athletes with sickle cell trait, sickled cells logjam in the muscle capillaries

31. Why do athletes with sickle cell trait die?
With little or no circulation in the muscle, the muscle starves for oxygen, lactic acid accumulates, and the muscle is damaged
High levels of K+ and Myoglobin are released into the blood causing heart arrythmias and kidney failure
Cardiac arrest soon follows
The process is rapid and difficult to treat

39. The symptoms of muscle sickling
Sickling collapse has been mistaken for cardiac collapse or heat collapse.
But unlike sickling collapse, cardiac collapse tends to be “instantaneous,” has no “cramping” with it, and the athlete (with ventricular fibrillation) who hits the ground no longer talks.
Unlike heat collapse, sickling collapse often occurs within the first half hour on-field, as during initial windsprints.
Core temperature is not greatly elevated.

40. Symptoms continued
Heat cramping often has a prodrome of muscle twinges; whereas, sickling has none;
The pain is different – heat-cramping pain is more excruciating;
What stops the athlete is different – heat crampers hobble to a halt with “locked-up” muscles, while sickling players slump to the ground with weak muscles;

41. Physical Findings
Physical findings are different – heat crampers writhe and yell in pain, with muscles visibly contracted and rock-hard; sicklers lie fairly still, not yelling in pain, with muscles that look and feel normal;
The response is different – sickling players caught early and treated right recover faster than players with major heat cramping
Most importantly, athletes with sickling can tell the difference between regular cramps, heat problems, and sickling

42. When does sickling occur?
Sickling players may be on-field only briefly, sprinting only 800-1,600 meters, often early in the season.
Sickling can also occur during repetitive running of hills or stadium steps, during intense sustained strength training, if the tempo increases late in intense one-hour drills, or at the end of practice when players run “gassers.”
Sickling can even occur rarely in the game, as when a running back is in constant action during a long, frantic drive downfield .

43. What conditions predispose athletes to risk?
Hard conditioning runs
Station drills
Short rest intervals
Dehydration
Heat
Asthma

44. Treatment
The important thing to understand is that most athletes with sickling symptoms do not progress to muscle damage and death.
Simply slowing down the activity and allowing oxygen to re-enter the muscle will alleviate sickling symptoms quickly.

45. If the athlete collapses…
In the event of a sickling collapse, treat it as a medical emergency by doing the following:
Check vital signs.
Administer high-flow oxygen, 15 lpm, with a non-rebreather face mask.
Cool the athlete, if necessary.
If the athlete is obtunded or as vital signs decline, call 911, attach an AED, start an IV, and get the athlete to the hospital fast. .
Tell the doctors to expect explosive rhabdomyolysis and grave metabolic complications.
Proactively prepare by having an Emergency Action Plan and appropriate emergency equipment for all practices and competitions

46. IMMEDIATE ACTION CAN SAVE LIVES!

47. Prevention
1) Build up slowly in training with paced progressions, allowing longer periods of rest and recovery between repetitions.
2) Exclude from participation in "preseason/day-1 conditioning tests”. Several deaths have occurred from participation in this setting.
3) Cessation of activity with onset of symptoms: muscle ‘cramping’, pain, swelling, weakness, tenderness; inability to "catch breath", fatigue

48. Prevention 4) Control the environment.
a. Adjust work/rest cycles for environmental heat stress
b. Emphasize hydration
c. Control asthma
d. No workout if an athlete with sickle trait is ill.
5) Attention is warranted, especially to the athlete with sickle cell trait who is new to altitude. Modify training and have supplemental oxygen available for competitions

49. Running precautions
Most athletes with sickle cell trait will never have a problem during practice
All cases of football sickle cell trait death have occurred during high intensity sprinting orstation drills
Sprinting longer than 10 seconds creates high lactic acid levels which require a minimum of 2-3 minutes to recover (longer rest periods for longer distances)

50. Prevention
Create an environment that fosters acceptance and understanding of athletes with this condition. Remember, most of these athletes will never have a problem and will lead a totally normal life.

51. Thank You!