10.3 Medical Collapse: Anaphylaxis, Asthma, Diabetes, Sickle Cell & ECAST
Key Takeaways
- Anaphylaxis: intramuscular epinephrine into the anterolateral thigh (vastus lateralis) is first-line (WAO 2020). Antihistamines and steroids are adjuncts—do not start with diphenhydramine while the athlete is hypotensive or closing the airway.
- Asthma: SABA (albuterol), sitting, oxygen; EMS for silent chest, failure after sequential SABA (NATA: if three administrations do not relieve, refer promptly), or impending respiratory failure.
- Hypoglycemia vs DKA: use a glucometer. Conscious hypo: 15 g fast carbohydrate, recheck in 15 minutes (15-15 rule) if they can swallow. Unconscious: no oral glucose; glucagon if trained/protocol allows; EMS. DKA is a hospital insulin-and-fluids problem.
- ECAST/exertional sickling: often early-season intense conditioning; the athlete may still talk; severe muscle pain and weakness. Medical emergency: high-flow O2 at 15 L/min via non-rebreather, cool if needed, IV fluids per protocol, EMS. Do not stretch it like a heat cramp. Contrast with SCA, which is unresponsive immediately.
- Seizure: protect, do not restrain, nothing in the mouth, time it, recovery position after, EMS if first, prolonged (≥5 min), recurrent, or the athlete does not return to baseline. Exertional hyponatremia is a collapse/seizure mimic previewed here and treated in Chapter 12.
Quick Answer: Anaphylaxis → IM epinephrine in the anterolateral thigh first, then airway, oxygen, EMS, and antihistamines as adjuncts—never diphenhydramine first. Asthma → SABA, sitting, oxygen; EMS if silent chest or not responding. Diabetes → glucometer; 15-15 rule if conscious; glucagon/EMS if unconscious; no oral glucose in an unconscious athlete. Sickle cell trait / ECAST → still talking, severe muscle pain after intense early-season work; high-flow oxygen 15 L/min non-rebreather, cool, IV fluids per protocol; do not stretch it like a cramp. Seizure → protect, time, nothing in the mouth.
PA8 Domain III task 0303 is not only VF and BVM. Most ‘medical collapses’ you will see are still talking—and that is how people die when you treat ECAST as a cramp or anaphylaxis as ‘just hives.’
Collapse differential at a glance
| Condition | Responsiveness | Hallmark | First field move |
|---|---|---|---|
| SCA | Unresponsive immediately; agonal gasps | No effective pulse | CPR + AED |
| Anaphylaxis | Usually conscious at first | Two systems or hypotension after allergen | IM epinephrine |
| Asthma | Conscious, sitting forward | Expiratory wheeze; silent chest is failure | SABA + O2; EMS if failing |
| Hypoglycemia | Confused → unresponsive | Sweat, tremor, known diabetes, low glucometer | 15 g carbs if they can swallow |
| DKA / severe hyperglycaemia | Ill, often still conscious | High glucose, ketones, Kussmaul, fruity breath | EMS; no field insulin unless protocol |
| ECAST / exertional sickling | Often still talking | Weakness, pain, slump during intense conditioning | High-flow O2, stop work, EMS |
| Heat cramp | Talking, localized spasm | Palpable contracted muscle | Rest, stretch that cramp, sodium/fluids—not ECAST care |
| Seizure | Unresponsive during event | Tonic-clonic; post-ictal | Protect, time, recovery position |
| Exertional hyponatremia | Confused, may seize | Overdrinking, weight gain, long event | Preview: Chapter 12; EMS if neurologic |
Anaphylaxis: epinephrine first
World Allergy Organization 2020 guidance: intramuscular epinephrine (adrenaline) is first-line. Inject into the vastus lateralis—anterolateral thigh. Remove the trigger if you can (stinger, ongoing food). Call EMS. Position: supine with legs elevated if hypotensive; sitting if they cannot breathe flat; left lateral if vomiting. Do not make a hypotensive athlete stand or walk to the bus.
Do not start with diphenhydramine. H1 blockers may ease itch and hives; they do not reverse shock, airway edema, or mast-cell mediator surge on the timeline that keeps people alive. Glucocorticoids are not first-line for the first five minutes. Inhaled β2 agonists may help wheeze after epinephrine. The exam item is always: epi first, then the rest.
Dosing is device- and standing-order specific. Adult autoinjectors in the United States are commonly 0.3 mg IM; junior devices commonly 0.15 mg; guideline weight-based IM dosing is often cited as 0.01 mg/kg (typical published single-dose maximum 0.5 mg of 1:1000 IM). ATs give what the physician protocol and the labeled autoinjector authorize, through clothing if needed, and may repeat in about 5–15 minutes if the athlete is not improving when the written order allows a second dose. Do not mix IV push epinephrine from an ACLS ampoule unless that is explicitly in your ALS protocol—that is a different concentration and a different scope.
Anaphylaxis can look like asthma. If the story is a sting, peanut, or unknown exposure plus skin, gut, or hypotension, it is not ‘just EIB.’ Give epinephrine. Delayed or ‘wait and see’ antihistamine care is how fatal anaphylaxis is missed.
Asthma: SABA, position, oxygen, know when you have lost
NATA’s asthma position statement: every asthmatic athlete should have a rescue inhaler at practice and games, and the AT should have a spare. Sit the athlete up. Give albuterol (SABA)—typically 2 puffs; onset often 5–15 minutes. Severe exacerbations may need rapid sequential SABA. Offer oxygen. NATA 2012 Preventing Sudden Death in Sports: if three administrations do not relieve distress, refer promptly. Silent chest, cyanosis, collapsing peak flow (if you measure it), inability to speak phrases, exhaustion, or altered mentation is EMS now, not another timeout huddle.
If asthma and anaphylaxis are both plausible (known asthma plus allergen plus hypotension or swelling), epinephrine first, then asthma meds. That is also pediatric emergency teaching and it belongs on the sideline.
Diabetes: glucometer, 15-15, nothing in an unconscious mouth
Check the glucose. Do not guess. Hypoglycemia and DKA can both look ‘off.’
Hypoglycemia (commonly treat at ≤70 mg/dL, athlete-specific action plans may use a slightly higher pre-exercise floor such as 100 mg/dL before they start):
- Conscious and can swallow: 15-15 rule (American Diabetes Association teaching): give about 15 g of fast carbohydrate (glucose tablets, 4 oz juice, gel—not a protein bar), wait 15 minutes, recheck, repeat if still low, then a snack with protein/complex carb once they are stable. NATA 2007 type 1 diabetes position statement used 10–15 g for mild events; teach 15-15 as the current field phrase and follow the athlete’s written plan.
- Unconscious, seizing, or cannot protect the airway: do not give oral glucose, juice, or gel in the mouth—aspiration kills. Glucagon (IM/SQ kit or nasal powder such as Baqsimi) if you are trained and the protocol/athlete’s plan includes it, plus EMS, plus airway. Glucagon mobilizes hepatic glycogen; it fails if glycogen is empty (alcohol, prolonged starvation). After glucagon, expect vomiting; recovery position when the seizure/unresponsiveness lifts.
DKA / severe hyperglycemia: high glucometer (often >250 mg/dL with ketones in classic definitions), polyuria/polydipsia, abdominal pain, Kussmaul (deep rapid) breathing, fruity acetone breath, dehydration. This is insulin deficiency, not a sugar deficit. Do not push oral glucose ‘just in case’ if you have a high reading and a protected airway. Do not give insulin on the field unless a specific physician protocol says so—most athletic protocols do not. EMS, oxygen if needed, nothing by mouth if they are obtunded.
If you cannot get a reading and the athlete is a known insulin user who is unresponsive, treat as hypoglycemia (glucagon/EMS/airway). A little extra glucose will not fix DKA and will not kill as fast as untreated severe hypo.
Sickle cell trait and ECAST: not a cramp, not SCA
Sickle cell trait (SCT) is one sickle gene. Athletes can play; they are not disqualified (NATA 2007 Sickle Cell Trait and the Athlete consensus; AHA/ACC eligibility statements). Under intense exertion—especially early-season conditioning, repeats with high lactic acid, heat, dehydration, altitude, illness, or asthma—red cells can sickle, occlude muscle, and produce exertional collapse associated with sickle cell trait (ECAST) / exertional sickling. NCAA Division I football players with SCT have been reported at tens of times higher death risk than those without in older epidemiologic papers (often cited ~37×). The American Society of Hematology has more recently cautioned against listing ‘sickle crisis’ as a cause of death without rhabdomyolysis or heat injury; that debate does not change the sideline rule: a collapsing SCT athlete is a medical emergency.
Picture that is not SCA: the athlete is usually still conscious and talking, may slump to the ground, complains of severe muscle pain, weakness, ‘cramping’ that is more ischemic than a contracted knot, low-back or thigh pain, and cannot catch their breath. It often happens in the first few minutes of all-out work, not after two hours of tennis in the sun. SCA hits the ground and does not talk. Heat cramp is a rock-hard, palpable, stretchable muscle in a talking athlete who is otherwise stable.
Exam trap: stretching a collapsing SCT athlete’s legs as if it were a heat cramp. Forcing stretch on ischemic, sickled muscle is the wrong treatment and wastes minutes.
NATA 2007 treatment (still the athletic teaching sequence):
- Check vital signs; stop activity immediately.
- High-flow oxygen, 15 L/min, non-rebreather if available.
- Cool if they are hot.
- If obtunded or vitals decline: 911, AED attached, IV normal saline if in protocol, hospital fast.
- Tell receiving clinicians to expect explosive rhabdomyolysis and grave metabolic complications (hyperkalemia, acidosis, compartment syndrome, death).
IV fluids are protocol/physician-order specific; many college EAPs include them for this exact emergency. Do not withhold oxygen while you argue about whether ASH or NATA ‘owns’ the pathophysiology. Attach an AED because ECAST can deteriorate to arrest from metabolic disaster; the first presentation is still not the unresponsive VF collapse of 10.1.
Prevention (you will be asked): year-round conditioning, extended rest between sprints, no punishment drills that chain all-out repeats, hydration, caution at altitude, and stop at the first symptom. Any fatigue, dyspnea, or ‘cramp’ in an SCT athlete is sickling until proven otherwise.
Seizure
Protect the head, move hazards, do not restrain, do not put a bite stick, fingers, or a mouthguard back in, time the event, and note cyanosis, incontinence, and focal onset if you see it. After convulsive activity stops, recovery position if they are breathing and no trauma forces you to stay supine with a jaw-thrust. EMS if it is a first seizure, ≥5 minutes (status epilepticus is continuous seizure ≥5 minutes or recurrent without recovery), serial seizures, pregnancy, diabetes, head trauma, water, or they do not return toward baseline. Brief myoclonus at the moment of SCA is not this algorithm—if they collapsed unresponsive and are not breathing normally, you are in 10.1, not epilepsy clinic.
Exertional hyponatremia preview
Altered mentation, headache, vomiting, and seizure after a long event in an athlete who overdrank hypotonic fluid and may have gained weight is exertional hyponatremia, not garden-variety dehydration. Do not blast free water. Full recognition and sodium treatment live in Chapter 12 (environmental/exertional). On this chapter’s exam items, know it is in the differential of medical collapse and seizure, and that it is not treated with more water or with stretching.
A soccer player is stung, develops hives, wheeze, and light-headedness with a falling blood pressure. Which treatment order matches WAO and sideline best practice?
During the first week of August conditioning, a football athlete with sickle cell trait slumps after repeat 300-yard shuttles. He is on the ground, still talking, and screaming that both thighs are weak and painful. Coaches start stretching his hamstrings ‘like a heat cramp.’ What should the athletic trainer do?
A tennis player with type 1 diabetes is unresponsive on the sideline. A glucometer reads 38 mg/dL. She is breathing but cannot follow commands or swallow. What is the correct glucose plan?