2014 CORK CITY MARATHON

CIAN O’BRIEN

OVERVIEW

Cork City Marathon Overview

Case Studies

Research

Event Medical Plan

WHAT IS A MARATHON? It is named after the Greek Battle of Marathon

After the Greeks were victorious over the Persians at the Battle of Marathon, they sent a runner to Athens with the news

The runner, ran the entire distance to Athens without stopping, announced the victory, and then dropped dead, due to the physical stress on his body

A marathon is an endurance foot race which covers 26 miles, 385 yards (42.2 kilometers)

CORK CITY MARATHON

Full Marathon

• 26 miles 385 yards/42.195 km• Full Association of International Marathons and Distances

Races

Half Marathon

• 21.1 km

Relay Event

Youth Team Relay

• Open to all 2nd level students who will be aged 16 years or older on 2nd June 2014.

THE PHYSIOLOGY OF MARATHON RUNNING

• Running a marathon has been viewed, and still is by many, as too extreme to be healthy.

• Physical stress of running a marathon played some role in not holding a women's Olympic marathon race until 1984

• It should be respected for the physiological stress inflicted over its 26.2 miles

Running a five-minute-per-mile marathon requires a

15-fold increase in energy production for over two hours

Runners who finish in over four hours maintain a

10-fold increase in their metabolism

Extended energy demands require the cardio, respiratory, endocrine, and neuromuscular systems to operate at an elevated level for an inordinate length of time

DIFFERENTIAL DIAGNOSISABDOMINAL PAIN

CASE STUDY 1John O Sullivan 39 year old

Bib Number 5025 (Full Marathon event)

Mile Marker – 14

Alerted by marathon volunteers

Chief Complaint – Disorientated

Vitals Signs

HR – 145 regular

BR – 34 fast

SP02 – 94%

1 2

3

FINAL DIAGNOSIS IN MEDICAL CENTRE

HYPERTHERMIA

HYPERTHERMIA• The heart helps control body temperature by pumping warm

blood to the skin where body heat is lost through the evaporation of sweat

• During a marathon, heat loss and production can increase over 10-fold

• High humidity and dehydration can make heat loss more difficult

• High humidity levels reduce evaporation, while dehydration impairs the ability to transfer heat from the muscles to the skin

• Either situation will increase body temperature and the risk for heat problems

HYPERTHERMIA• Muscle weakness and disorientation can develop with body

temperatures of 40 degrees Celsius,

• A loss of consciousness can occur with body temperatures near 41.5 degrees Celsius

HYPERTHERMIA• Hyperthermia, during marathon running can be due to

• Climate,• Dehydration, • High metabolic rate from running a faster-than-usual pace

• Marathon runners may overdress or not remove layers or clothing as the air temperature rises over the course of the marathon

HYPERTHERMIA

• The average sweat rate for runners is 1.2 liters per hour

• Most runners either can't tolerate drinking that much or choose not to drink that much liquid

• Typically, runners drink as little as 200 milliliters per hour but rarely more than 1 liter per hour

• Therefore, it is not uncommon for runners to lose 2 to 10 % of their body weight through sweating

HYPERTHERMIA

• Towards the end of a marathon, when the speed and effort of running increase, the body becomes less efficient at using energy, which produces more excess heat, which in turn drives the body temperature even higher

CASE STUDY 2

Ann Aherne 27 years oldMile Marker 10.5Bib Number 1141 (Half Marathon Event)Alerted by marathon volunteersChief Complaint: disoriented, vomiting

Vital SignsHR 168 regularBR: 28 fast & ShallowSP02 – 93%Temp – 37.8

1 2

3

FINAL DIAGNOSIS IN MEDICAL CENTRE

HYPONATREMIA

Exercise-Associated

HYPONATREMIA

• A low sodium concentration in the blood

• <135mmol/L• Sodium is an electrolyte that helps with nerve and muscle

function, and also helps to maintain BP.

HYDRATION STRATEGIES

HYPONATREMIA• The major cause of hyponatremia = is drinking too much

water, which dilutes sodium levels in the blood

• Low sodium levels cause swelling or edema in the brain, which can be fatal

Davis et al. (2001) found 26 cases of hyponatremia in over 34,000 runners from the 1998 and 1999 San Diego Rock 'n' Roll

Marathon

• They found that hyponatremia was

• greater in women• slower runners (those who finish in over four hours)

• NSAIDs

Why women? • Less water can dilute sodium levels in

smaller bodies

• Estrogen can further contribute to brain swelling once it starts

Why slow runners? • Slower runners are at a greater risk simply

because they have more time during a marathon to drink too much water

Why NSAIDs?• NSAIDs increase the effect of ADH

Which increases water retention

• Hyponatremia can develop after completion of a marathon when

• Hormonal changes cause increases in absorption of water• Sodium lost in the urine

DIAGNOSIS & TREATMENT

CASE STUDY 3

Sean Lynch 64 years old Bib Number 18978Mile Marker: Finish Line (Full Marathon)Chief Complaint: Disorientated, Shivering & Generally unwell

Vital Signs HR – 68 regularBR – 24 shallow SP02 – un-recordable

1 2

3

FINAL DIAGNOSIS IN MEDICAL CENTRE

Hypothermia

• Hypothermia can be the main environmental concern for marathon runners

• The risk for hypothermia is greater in cold, windy, or wet weather

• If the second half of the marathon is run slower than the first half, not enough heat may be generated to maintain body temperature

• Any sweat that builds up can saturate clothing, which will draw additional heat away from the body

CASE STUDY 4

Sarah Boylan 21 years old

Bib Number: 705

Mile Marker: 18 (Relay Event Change Over Point)

Chief Complaint: Generally unwell, disorientated, nausea, sweating, combatative

Vital Signs

HR – 102 irregular & weak

BR – 34 shallow & fast

SP02 – 92%

1 2

3

FINAL DIAGNOSIS IN MEDICAL CENTRE

Hypoglycaemia

• A blood sugar level <4.0mmol/L

• The brain prefers glucose as its fuel

• Hypoglycemia impairs brain functions

• May occur in Diabetic, or non diabetic runners when not enough carbohydrates are consumed during the race

GLYCOGEN DEPLETION• Carbohydrates provide energy to the muscles faster than fats

• Inside the body, carbohydrates are found as glycogen in the muscles and liver and as glucose in the blood

• As the amount of glucose in the blood is used up, the liver converts its glycogen into glucose and releases it into the bloodstream to maintain a constant supply of glucose to the muscles

Signs & Symptoms may include,

• Altered mental state,

• Sweating,

• Fatigue,

• Tachycardia,

• Palpitations,

• Hunger,

• Headache

• Slurred speech.

• (Medical alert tag)

Treatment?

INJURY

30,000 - 50,000

steps to run a marathon

Every time the foot hits the ground, a stress three to four times body weight is absorbed by the ankles, knees, hips, and lower back

INJURY EPIDEMIOLOGY

Most common being knee pain, hamstring problems,

dehydration, blisters

The injury rate from 12 years of the Twin Cities Marathon was 2.1 percent of all runners (21.15 per 1,000 entrants), with the top five injuries being:

Exercise-associated collapse 59.4 %

Blisters - 19.9 %

Muscle strain - 14.3 %

Muscle cramps - 6.1 %

Skin abrasions - 1.9 %

BLISTERS – 19.9%

MUSCLE STRAINS – 14.3%

FACTORS THAT INCREASE RISK OF INJURY• 1st marathon

• Participation in other sports

• Illness 2/52 prior

• Current use of medication

• Training mileage

Runners who train less than 60 kilometers per week were more likely to become injured while running a marathon

Higher levels of training have been shown to decrease the risk for knee injuries but increase the risk of injury to the quadriceps and hamstrings during a marathon

ELITE RUNNERS

ELITE RUNNERS

Copenhagen Marathon found the most common problem in elite runners was:

Gastrointestinal (GI) distress - 26 %

Back or joint pain - 20 %,

Muscle cramps -16 %

Blisters and other skin lesions - 16 %

Elite runners who suffer from GI distress secrete higher levels of GI hormones or consume higher amounts of NSAIDs

CASE STUDY 4• Paul Ahern 37 years old

• Bib Number 234

• Mile Marker 19

• Chief Complaint – Collapse/unresponsive

• Agonal breathing, can’t located pulse

• AMPLE – not available

1 2

3

CARDIAC ARREST

How common is it really?

✖ ✔

EXERCISE-ASSOCIATE COLLAPSE

• A collapse in conscious runners who are unable to stand or walk unaided, as a result of dizziness, faintness or light headedness.

• This collapse usually occurs after a runner stops exercising

EXERCISE ASSOCIATED COLLAPSE• This happens because during exercise the muscles of the

lower limbs require an increased blood flow. These muscles then act like a ‘second heart’ ensuring that this blood is returned to the heart assisted by the contraction of the leg muscles.

• When a runner suddenly stops exercising (e.g. finish line) the body’s ‘second heart’ stops functioning and blood pools in the legs, inducing exercise associated collapse.

EXERCISE ASSOCIATED COLLAPSE• EAC is the most common condition seen at finish line medical

tents

• Signs & Symptoms of EAC include:

• Abnormal body temp• Altered mental state, • Altered LOC, • CNS changes• Ambulation problems• Muscle spasms• Tachycardia• Vomiting/Diarrhoea

• Before treating EAC attention must be focused on ruling out other causes of collapse by performing:

• Vital Signs• BSL • ECG• Blood tests• Rectal Temp • AMPLE history

• Treatment of EAC involves fluid redistribution and replacement in the body to improve cerebral and vital organ perfusion.

• The redistribution of blood in the body is assisted by the positioning of the patient.

• With symptoms improving in 5-30 minutes.

• Trendelenburg Position

DISCHARGE CRITERIA FOR RUNNERS

Normal Mental Status/ GCS 15/15

‘Normal’ Vital Signs

Ability to mobilise

Carry out a ‘sit-test’

Warm dry clothing

Discharged to a responsible adult

Diet and hydration advice and ED/GP follow as required

OTHER RUNNING INJURIES TO CONSIDER

Runners Nipple

Stress Fractures

Sprains & Strains RICE

Lung Injury

Exercise Associated Muscle Cramps

Blisters/Cuts/Grazes

MARATHON FIELD HOSPITAL

WHERE WE’VE COME FROM?

WHERE WE ARE GOING…• Following international best practice we will continue to

develop the service we provide.

• Carrying out Research

• Providing Evidence Based Practice

• Looking outside the box.

• Becoming affiliated with the International Marathon Medical Directors Association.

RESEARCHER – CIAN O’BRIEN

The Epidemiology of Illness and Injury at the 2014 Cork City Marathon (O’Brien et al, 2015)

Questions?

Nothing too hard, please!

MEDICAL EVENT PLAN

QUESTIONS