Environmental Emergencies Paramedic

Environmental ConditionsEnvironmental Conditions

ObjectivesObjectives

Define “environmental emergency” and list the major Define “environmental emergency” and list the major types.types.

Identify risk factors most predisposing to environmental Identify risk factors most predisposing to environmental emergencies.emergencies.

Identify environmental factors that may cause illness or Identify environmental factors that may cause illness or exacerbate a preexisting illness and those that may exacerbate a preexisting illness and those that may complicate treatment or transport decisions.complicate treatment or transport decisions.

Describe the mechanism of normal body temperature Describe the mechanism of normal body temperature regulation and identify normal, critically high and regulation and identify normal, critically high and critically low body temperatures.critically low body temperatures.

Describe several methods of temperature monitoring.Describe several methods of temperature monitoring. Identify mechanisms by which the body loses and retains Identify mechanisms by which the body loses and retains

heat.heat.


Discuss the pathophysiology, high risk groups, signs and Discuss the pathophysiology, high risk groups, signs and symptoms, and field treatment of the following:symptoms, and field treatment of the following:

Heat crampsHeat cramps Heat exhaustionHeat exhaustion Heat stroke (classic and exertional)Heat stroke (classic and exertional)

Define fever and discuss its pathophysiologic mechanism.Define fever and discuss its pathophysiologic mechanism. Identify the fundamental thermoregulatory difference between Identify the fundamental thermoregulatory difference between

fever and heatstroke and discuss how one may differentiate fever and heatstroke and discuss how one may differentiate between the two.between the two.

Discuss the pathophysiology, high risk groups, signs/symptoms, Discuss the pathophysiology, high risk groups, signs/symptoms, field treatment and prevention of the following:field treatment and prevention of the following:

FrostbiteFrostbite HypothermiaHypothermia SuperficialSuperficial MildMild DeepDeep SevereSevere


Discuss the importance of attempting resuscitation in Discuss the importance of attempting resuscitation in a pulse less hypothermic patient.a pulse less hypothermic patient.

List factors that contribute to drowning.List factors that contribute to drowning. Differentiate between and describe the Differentiate between and describe the

pathophysiology, signs/symptoms and field treatment pathophysiology, signs/symptoms and field treatment of drowning and near-drowning.of drowning and near-drowning.

Differentiate between the effects of salt vs. fresh Differentiate between the effects of salt vs. fresh water on the lungs and circulatory system in drowning.water on the lungs and circulatory system in drowning.

Discuss the incidence of “wet” vs. “dry” drowning and Discuss the incidence of “wet” vs. “dry” drowning and the differences in their management.the differences in their management.

Describe the effects of cold water on drowning Describe the effects of cold water on drowning patients.patients.


Define self-contained underwater breathing Define self-contained underwater breathing apparatus.apparatus.

Describe the pathophysiology, signs/symptoms Describe the pathophysiology, signs/symptoms and field treatment for the following diving and field treatment for the following diving emergencies:emergencies: Decompression illnessDecompression illness b.b. Air embolismAir embolism

Describe the function of the Divers Alert Network Describe the function of the Divers Alert Network (DAN) and how its members may aid in the (DAN) and how its members may aid in the management of diving related illnesses.management of diving related illnesses.

Describe the specific function and benefit of Describe the specific function and benefit of hyperbaric oxygen therapy for the management hyperbaric oxygen therapy for the management of diving accidents.of diving accidents.

ScenarioScenarioYou respond to an athletic field at 3:00 You respond to an athletic field at 3:00 p.m. for a “person down.” It is hot and p.m. for a “person down.” It is hot and humid. You know that the college football humid. You know that the college football team started practice this week. Your team started practice this week. Your patient is an unconscious 21-year-old, 230 patient is an unconscious 21-year-old, 230 pound male. His skin is wet and very hot. pound male. His skin is wet and very hot. Vital sign assessment reveals: BP 82/64 Vital sign assessment reveals: BP 82/64 mm Hg; HR 136/min; R 28/min. As you mm Hg; HR 136/min; R 28/min. As you administer oxygen, he has a grand mal administer oxygen, he has a grand mal seizure. seizure.

DiscussionDiscussion What factors point to a heat-What factors point to a heat-

related emergency on this call?related emergency on this call? What other emergencies should What other emergencies should

you rule out?you rule out? Describe additional assessments Describe additional assessments

that should be donethat should be done Outline your priorities of care Outline your priorities of care

based on your current informationbased on your current information

Environmental emergencyEnvironmental emergency

Medical condition caused or Medical condition caused or exacerbated by weather, terrain, exacerbated by weather, terrain, atmospheric pressure, or other local atmospheric pressure, or other local factors factors

A medical emergency resulting from A medical emergency resulting from physical exposure to the environmental physical exposure to the environmental elements – water, heat, humidity, cold, elements – water, heat, humidity, cold, altitude, windaltitude, wind

ThermoregulationThermoregulation

Regulatory center - Hypothalamus Regulatory center - Hypothalamus

Peripheral thermoreceptorsPeripheral thermoreceptors

Central thermoreceptorsCentral thermoreceptors

ThermoregulationThermoregulation

Body temperature increased or Body temperature increased or decreased by:decreased by: Regulation of heat productionRegulation of heat production

ThermogenesisThermogenesis Regulation of heat loss Regulation of heat loss

ThermolysisThermolysis

Normal body temperature is 37 degrees Centigrade Normal body temperature is 37 degrees Centigrade or or 98.698.6 F, though it may range from F, though it may range from 96.5-99.96.5-99.5o 5o

(Recent studies show that (Recent studies show that 98.2o98.2o is more average) is more average)

Your body temp fluctuates daily – sleep vs exercise, Your body temp fluctuates daily – sleep vs exercise, etc.etc.

Extremely elevated body temperatures can cause Extremely elevated body temperatures can cause multisystem damage and physiological collapse: multisystem damage and physiological collapse:

(>105.8oF or 41oC(>105.8oF or 41oC))

Body temperatures below 90oF (32C) cause Body temperatures below 90oF (32C) cause decreased LOC, poor judgment, the cessation of decreased LOC, poor judgment, the cessation of

shivering, and uncoordination.shivering, and uncoordination.

Body temperatures below 82.4oF (28C) usually Body temperatures below 82.4oF (28C) usually result in unconsciousness and possible vfib.result in unconsciousness and possible vfib.

Regulating Heat ProductionRegulating Heat Production MuscularMuscular

Baseline muscular activityBaseline muscular activity ExertionExertion ShiveringShivering

MetabolicMetabolic Processing of food and nutrientsProcessing of food and nutrients

Carbohydrates (sugars and starches)Carbohydrates (sugars and starches) FatsFats ProteinsProteins

GlycogenGlycogen EndocrineEndocrine

Role of hormones in basal metabolic rateRole of hormones in basal metabolic rate

Regulating Heat LossRegulating Heat Loss Radiation Radiation Heat waves rise off of our skin (head) Heat waves rise off of our skin (head)

This starts to be ineffective above 88 degrees. This starts to be ineffective above 88 degrees. Most body heat is lost through the skinMost body heat is lost through the skin

Conduction Conduction Heat loss by direct contact with Heat loss by direct contact with colder object- snow, icecolder object- snow, ice

Convection Convection Heat loss by moving air (wind chill, Heat loss by moving air (wind chill, ceiling fans)ceiling fans)

Evaporation Evaporation Any fluid absorbs heat from Any fluid absorbs heat from surrounding objects and air. We lose heat by surrounding objects and air. We lose heat by sweating, being wet or in wet clothes, and from sweating, being wet or in wet clothes, and from respirations. This is why animals pant! Sweating respirations. This is why animals pant! Sweating is only effective if humidity is low enough for the is only effective if humidity is low enough for the water to evaporate! Evaporative rate decreases water to evaporate! Evaporative rate decreases if humidity is above 75%. At levels approaching if humidity is above 75%. At levels approaching 90%, evaporation essentially ceases.90%, evaporation essentially ceases.

Hyperthermia CompensationHyperthermia Compensation

Hyperthermia compensationHyperthermia compensation Increased heat lossIncreased heat loss

Vasodilation of skin vesselsVasodilation of skin vessels SweatingSweating

Decreased heat productionDecreased heat production Decreased muscle tone and voluntary Decreased muscle tone and voluntary

activityactivity Decreased hormone secretionDecreased hormone secretion Decreased appetiteDecreased appetite

Hypothermic CompensationHypothermic Compensation

Decreased heat lossDecreased heat loss Peripheral vasoconstrictionPeripheral vasoconstriction Reduction of surface area by body position Reduction of surface area by body position

(or clothing)(or clothing) Piloerection (not effective in humans)Piloerection (not effective in humans)

Hypothermic CompensationHypothermic Compensation

Increased heat productionIncreased heat production ShiveringShivering Increased voluntary activityIncreased voluntary activity Increased hormone secretionIncreased hormone secretion Increased appetiteIncreased appetite

External Environmental FactorsExternal Environmental Factors

May contribute to a medical May contribute to a medical emergencyemergency

ClimateClimate SeasonSeason WeatherWeather Atmospheric pressureAtmospheric pressure TerrainTerrain

Predisposing FactorsPredisposing Factors History of exposureHistory of exposure Poor planning, preparation, educationPoor planning, preparation, education Conditioning, health, nutritional status, Conditioning, health, nutritional status,

other illnesses or associated traumaother illnesses or associated trauma AgeAge Use of alcohol, drugs, and prescription Use of alcohol, drugs, and prescription

medicationsmedications PovertyPoverty

Environmental FactorsEnvironmental Factors Heat HumidityHeat Humidity

Cold WaterCold WaterWind AltitudeWind Altitude

Possible remote location and delay in identifying Possible remote location and delay in identifying problemproblem

(lost person) and accessing EMS(lost person) and accessing EMS

Difficulty in accessing or extricating patientDifficulty in accessing or extricating patient(identifying lack of contact with elderly who lives (identifying lack of contact with elderly who lives

alone in aalone in a common urban scenario)common urban scenario)

HyperthermiaHyperthermia Thermoregulatory mechanisms Thermoregulatory mechanisms

overwhelmed by:overwhelmed by: Environmental conditionsEnvironmental conditions

Heat stressHeat stress Excessive exercise in moderate to Excessive exercise in moderate to

extreme environmental conditionsextreme environmental conditions Failure of thermoregulatory Failure of thermoregulatory

mechanismsmechanisms Older adults or ill or debilitated patientsOlder adults or ill or debilitated patients

Either may result in heat illnessEither may result in heat illness

Heat CrampsHeat Cramps Brief, intermittent, often severe Brief, intermittent, often severe

muscular cramps occuring in muscular cramps occuring in muscles fatigued by heavy work or muscles fatigued by heavy work or exercise. Caused primarily by a exercise. Caused primarily by a rapid change in extracellular fluid rapid change in extracellular fluid osmolarity resulting from sodium osmolarity resulting from sodium and water loss.and water loss.

Heat CrampsHeat Cramps

1-3 L of water per hour may be lost through1-3 L of water per hour may be lost through

Sweating.Sweating.

Each liter contains between 30 and 50 mEq Each liter contains between 30 and 50 mEq

of sodium chloride. of sodium chloride.

Muscle cramping is caused by the water andMuscle cramping is caused by the water and

sodium loss.sodium loss.

Signs & SymptomsSigns & Symptoms

Alert, hot, sweaty skin, localized Alert, hot, sweaty skin, localized muscle cramps in extremities, muscle cramps in extremities, occasionally in abdomen. occasionally in abdomen.

Vital signs normal with tachycardia, Vital signs normal with tachycardia, BODY TEMP NORMAL; skin cool or BODY TEMP NORMAL; skin cool or slightly warmslightly warm

Field treatment:Field treatment: remove from hot remove from hot environment, replace the sodium and environment, replace the sodium and water (sodium especially), IV NaClwater (sodium especially), IV NaCl

HEAT EXHAUSTIONHEAT EXHAUSTION

Usually caused by exercising or Usually caused by exercising or exertion in hot ambient temperature, exertion in hot ambient temperature,

more severe water and salt more severe water and salt deficiency occurs. This electrolyte deficiency occurs. This electrolyte

imbalances causes vasomotor imbalances causes vasomotor regulatory disturbances and regulatory disturbances and

inadequate cerebral and peripheral inadequate cerebral and peripheral perfusion.perfusion.

Heat ExhaustionHeat Exhaustion More severe form of heat illnessMore severe form of heat illness

Temperature elevation (<103Temperature elevation (<103°° F [39 F [39°° C]) C])

Mental status changesMental status changes Nausea, headacheNausea, headache SweatingSweating ManagementManagement

Remove from heatRemove from heat Oral or IV fluidsOral or IV fluids

Signs & SymptomsSigns & Symptoms Minor aberrations in mental status, such Minor aberrations in mental status, such

as irritability, confusion, poor judgment, as irritability, confusion, poor judgment, headache, or light-headedness. Skin headache, or light-headedness. Skin pale with excessive sweating, slight or pale with excessive sweating, slight or no temperature increase no temperature increase (<103 (<103 degrees)degrees) Tachycardia, BP normal or Tachycardia, BP normal or slightly decreased, increased respiratory slightly decreased, increased respiratory raterate

Field treatmentField treatment includes removing the includes removing the patient from the hot environment, patient from the hot environment, oxygen, IV oxygen, IV

HEAT STROKEHEAT STROKE

Syndrome occurring when the Syndrome occurring when the thermoregulatory mechanisms that thermoregulatory mechanisms that normally cool the body fail normally cool the body fail completely. completely.

This results in a body temperature of This results in a body temperature of usually usually > 105.8o> 105.8o. Damage occurs . Damage occurs to the hypothalamus itself as a result to the hypothalamus itself as a result of prolonged exposure to heat.of prolonged exposure to heat.

Heat StrokeHeat Stroke Thermoregulatory mechanisms failThermoregulatory mechanisms fail

Body temperature >105.8Body temperature >105.8°° F [41 F [41° ° C])C]) Multisystem tissue damageMultisystem tissue damage Physiological collapsePhysiological collapse

Medical emergencyMedical emergency Two typesTwo types

Classic heat strokeClassic heat stroke Exertional heat strokeExertional heat stroke

Classic Heat StrokeClassic Heat Stroke

High temperatures and humidityHigh temperatures and humidity Risk factorsRisk factors

AgeAge Infants, elderlyInfants, elderly

Chronic illnessChronic illness Diabetes, heart disease, alcoholismDiabetes, heart disease, alcoholism

Medications Medications Psychotropics, diuretics, antihypertensivesPsychotropics, diuretics, antihypertensives

Exertional Heat StrokeExertional Heat Stroke Young, healthy patientsYoung, healthy patients

Athletes, military recruitsAthletes, military recruits

Vigorous exercise in high heatVigorous exercise in high heat

Inadequate hydrationInadequate hydration

No acclimationNo acclimation


Dizzyness, headache, bizarre or Dizzyness, headache, bizarre or unusual behavior, seizures, coma. unusual behavior, seizures, coma.

Vital signs include a normal or Vital signs include a normal or decreased BP, tachycardia with a decreased BP, tachycardia with a bounding pulse, tachypnea. bounding pulse, tachypnea.

Skin is usually hot, red, and dry, but Skin is usually hot, red, and dry, but may be wet or have wet clothing if may be wet or have wet clothing if exertional heatstroke. Temp is exertional heatstroke. Temp is highly elevated!highly elevated!

Heat StrokeHeat Stroke——AssessmentAssessment Confusion, coma, seizuresConfusion, coma, seizures Skin flushingSkin flushing Dry skin (25% sweat)Dry skin (25% sweat) Tachycardia, hypotensionTachycardia, hypotension Pulmonary edemaPulmonary edema Other systems affectedOther systems affected

Heat StrokeHeat Stroke——ManagementManagement Move to cool locationMove to cool location

Maintain airway, oxygen, ventilationMaintain airway, oxygen, ventilation Active coolingActive cooling

Fan wet skin Fan wet skin Ice PaksIce Paks

IV fluid: 500 mL over 15 minIV fluid: 500 mL over 15 min For hypotensionFor hypotension

Medications as prescribedMedications as prescribed Sedation, seizure controlSedation, seizure control ECG - ECG -

FEVERFEVER

Increased body temperature kills many Increased body temperature kills many microorganisms and has adverse effects of microorganisms and has adverse effects of the growth and replication of othersthe growth and replication of others

Body temperature decreases serum levels Body temperature decreases serum levels of iron, zinc, and copper, all of which are of iron, zinc, and copper, all of which are needed for bacterial replicationneeded for bacterial replication

Body temperature causes lysosomal Body temperature causes lysosomal breakdown and autodestruction of cells, breakdown and autodestruction of cells, thus preventing viral replication in infected thus preventing viral replication in infected cellscells

FEVERFEVER body temperature (heat) increases body temperature (heat) increases

lymphocytic transformation and lymphocytic transformation and motility of polymorphonuclear motility of polymorphonuclear neutrophils, thus facilitating the neutrophils, thus facilitating the immune responseimmune response

body temperature enhances body temperature enhances phagocytosisphagocytosis

body temperature may augment body temperature may augment the production of antiviral interferonthe production of antiviral interferon

HypothermiaHypothermia

Hypothermia Hypothermia

Marked decrease in the body’s core Marked decrease in the body’s core temperature. (or systemic cooling)temperature. (or systemic cooling)

FrostbiteFrostbite

Localized hypothermia (or freezing) of Localized hypothermia (or freezing) of the body’s tissues; more common in lower the body’s tissues; more common in lower extremities than upper, also seen in nose, extremities than upper, also seen in nose, ears, cheeks CBT less than ears, cheeks CBT less than 93.293.2°° F [34 F [34°° C]C]

HypothermiaHypothermia——PathophysiologyPathophysiology

VasoconstrictionVasoconstriction Sympathetic dischargeSympathetic discharge Shivering, tachycardiaShivering, tachycardia Shivering stops: Rapid coolingShivering stops: Rapid cooling Respiration, pulse, BP decreaseRespiration, pulse, BP decrease ECG changesECG changes Respiratory and cardiac arrestRespiratory and cardiac arrest

HypothermiaHypothermia

Progression of signs and symptoms Progression of signs and symptoms MildMild

Core temperature 93.2Core temperature 93.2°°-96.8-96.8°° F (34 F (34°°-36-36° ° C)C) ModerateModerate

Core temperature 86Core temperature 86°°-93-93°° F (30 F (30°°-34-34°° C) C) SevereSevere

Core temperature below 86Core temperature below 86°° F (30 F (30°° C) C)

HypothermiaHypothermia——Risk Risk FactorsFactors Outdoor enthusiastsOutdoor enthusiasts

Older adults, young childrenOlder adults, young children Medical/psychiatric illnessMedical/psychiatric illness TraumaTrauma MedicationsMedications

Alcohol, antidepressantsAlcohol, antidepressants Antipyretics, phenothiazinesAntipyretics, phenothiazines

HypothermiaHypothermia——ManagementManagement

High index of suspicionHigh index of suspicion Evacuate to warmthEvacuate to warmth Remove cold, wet clothesRemove cold, wet clothes Cover with warm blanketsCover with warm blankets Rapid transportRapid transport

HypothermiaHypothermia——ManagementManagement

Passive rewarmingPassive rewarming Move to warm environment and remove wet Move to warm environment and remove wet

clothesclothes Active external rewarmingActive external rewarming

Radiant heatRadiant heat Forced hot airForced hot air Warm IVFWarm IVF

Active internal rewarmingActive internal rewarming Warmed oxygenWarmed oxygen LavageLavage Cardiopulmonary bypassCardiopulmonary bypass

Mild HypothermiaMild Hypothermia——TreatmentTreatment

Passive rewarmingPassive rewarming Warm drinksWarm drinks

With sugarWith sugar External hot packsExternal hot packs No alcoholic beveragesNo alcoholic beverages Warm, heated oxygenWarm, heated oxygen

Moderate HypothermiaModerate Hypothermia——TreatmentTreatment

Can’t shiver or perform tasksCan’t shiver or perform tasks Passive rewarming firstPassive rewarming first

Keep patient at restKeep patient at rest External rewarmingExternal rewarming

Cover warm packs to prevent burnsCover warm packs to prevent burns Transport for evaluationTransport for evaluation

Severe HypothermiaSevere Hypothermia Support airway, ventilation and Support airway, ventilation and

circulationcirculation

Passive and external rewarmingPassive and external rewarming

OxygenOxygen

If ventricular fibrillation - start CPR and If ventricular fibrillation - start CPR and shock onceshock once

Rapid transportRapid transport

Considerations in Considerations in HypothermiaHypothermia

Assess for vital signs for 30-45 secAssess for vital signs for 30-45 sec If presence of pulse questionable - start If presence of pulse questionable - start

CPRCPR IntubateIntubate Sinus bradycardia may be protectiveSinus bradycardia may be protective

Pacing usually not indicatedPacing usually not indicated Withhold IV drugs until T>30CWithhold IV drugs until T>30C

If T>30C increase time between dosesIf T>30C increase time between doses

FrostbiteFrostbite

Localized injuryLocalized injury Freezing of body tissuesFreezing of body tissues PathophysiologyPathophysiology Predisposing factorsPredisposing factors

FrostbiteFrostbite——Classification/Classification/SymptomsSymptoms

Superficial frostbite (frostnip)Superficial frostbite (frostnip) Minimal tissue lossMinimal tissue loss

Deep frostbiteDeep frostbite Significant tissue loss even with Significant tissue loss even with

appropriate therapyappropriate therapy

Superficial FrostbiteSuperficial Frostbite

Some freezing of epidermal tissueSome freezing of epidermal tissue

Initial redness followed by blanchingInitial redness followed by blanching

Diminished sensationDiminished sensation

Deep FrostbiteDeep Frostbite Freezing of epidermal and Freezing of epidermal and

subcutaneous layerssubcutaneous layers White appearanceWhite appearance Hard (frozen) to palpationHard (frozen) to palpation Loss of sensationLoss of sensation pale, cold, yellow, bluepale, cold, yellow, blue

numb numb decreased movement decreased movement

Field ManagementField Management Remove patient from cold environmentRemove patient from cold environment Support the patient’s vital functions (be wary Support the patient’s vital functions (be wary

about systemic hypothermia)about systemic hypothermia) Rewarm in tepid (105o) H2O; no contact with Rewarm in tepid (105o) H2O; no contact with

containercontainer No rewarming if a possibility of refreezingNo rewarming if a possibility of refreezing No walking on frozen extremitiesNo walking on frozen extremities No coffee, alcohol, nicotineNo coffee, alcohol, nicotine No rubbingNo rubbing Remove wet and/or tight clothingRemove wet and/or tight clothing Wrap affected extremities in dry, sterile Wrap affected extremities in dry, sterile

dressings; then immobilizedressings; then immobilize

FrostbiteFrostbite

Edema and blister formation 24 hrs afterEdema and blister formation 24 hrs afterfrostbite injury in area covered by tightly fitted boot frostbite injury in area covered by tightly fitted boot

FrostbiteFrostbite

Gangrenous necrosis 6 wks after frostbite injury Gangrenous necrosis 6 wks after frostbite injury

Pulseless Hypothermic Pulseless Hypothermic Patient.Patient.

Hypothermic patients who appear dead Hypothermic patients who appear dead may still be successfully resuscitated. may still be successfully resuscitated.

The lowest recorded temperature that The lowest recorded temperature that an adult patient has survived in an adult patient has survived in accidental hypothermia is accidental hypothermia is 61oF.61oF.

Children especially have a better Children especially have a better chance of survival, some believe due to chance of survival, some believe due to the mammalian dive reflex.the mammalian dive reflex.

DrowningDrowning Fifth-leading cause of unintentional Fifth-leading cause of unintentional

deathdeath 85% male, 85% male, ⅔⅔ don’t know how to swim don’t know how to swim DrowningDrowning

Process that results in primary respiratory Process that results in primary respiratory impairmentimpairment

Caused by submersion/immersion in liquidCaused by submersion/immersion in liquid Liquid/air interface at airway prevents Liquid/air interface at airway prevents

breathingbreathing

Factors Contributing To Factors Contributing To DrowningDrowning

ETOH, drugsETOH, drugs TraumaTrauma Inability to swimInability to swim Stupidity, overconfidenceStupidity, overconfidence ExhaustionExhaustion Muscle crampsMuscle cramps Fear, panicFear, panic

Salt vs Fresh waterSalt vs Fresh water

SALTWATERSALTWATER

Hypertonic to body fluids; draws water Hypertonic to body fluids; draws water to it.to it.

Plasma and fluid move into the alveoli, Plasma and fluid move into the alveoli, resulting in pulmonary edema, poor resulting in pulmonary edema, poor ventilations of alveoli, hypoxia.ventilations of alveoli, hypoxia.

Salt vs. Fresh WaterSalt vs. Fresh Water

FRESHWATER FRESHWATER

Hypotonic to body fluids; moves out of Hypotonic to body fluids; moves out of alveoli into circulation. Blood volume alveoli into circulation. Blood volume can increase, causing RBCs to can increase, causing RBCs to rupture (hemolysis), and electrolyte rupture (hemolysis), and electrolyte abnormalities. Surfactant is “washed abnormalities. Surfactant is “washed out” or diluted, causing atelectasis, out” or diluted, causing atelectasis, then hypoxia in the alveoli.then hypoxia in the alveoli.

Submersion Incident - Submersion Incident - PathophysiologyPathophysiology

Wet vs. dry drowningWet vs. dry drowning Fluid in posterior oropharynx stimulates Fluid in posterior oropharynx stimulates

laryngospasmlaryngospasm Aspiration occurs after muscular relaxationAspiration occurs after muscular relaxation Suffocation occurs with or without aspirationSuffocation occurs with or without aspiration Aspiration presents as airway obstructionAspiration presents as airway obstruction

Fresh versus saltwater considerationsFresh versus saltwater considerations No difference in prehospital treatmentNo difference in prehospital treatment

Progression of a Drowning Incident Progression of a Drowning Incident

Drowning vs. Near-Drowning vs. Near-drowningdrowning

Drowning Drowning

Asphyxia after submersion (death <24 Asphyxia after submersion (death <24

hours)hours)

Near-drowningNear-drowning

Submersion accident where the patient Submersion accident where the patient

survives for at least 24survives for at least 24

DrowningDrowning

Hypothermic considerationsHypothermic considerations Common concomitant syndromeCommon concomitant syndrome May be organ protective in cold water May be organ protective in cold water

submersionsubmersion Treat hypoxia firstTreat hypoxia first Treat all submersion patients for Treat all submersion patients for

hypothermiahypothermia

Factors that Affect Clinical Factors that Affect Clinical OutcomeOutcome

Water temperature Water temperature

Length of submersionLength of submersion

Cleanliness of waterCleanliness of water

Age of patientAge of patient

Submersion IncidentSubmersion Incident——ManagementManagement ABCsABCs

Trauma considerationsTrauma considerations Spinal precautions if MOI suggests injurySpinal precautions if MOI suggests injury

Post resuscitation complicationsPost resuscitation complications Adult respiratory distress syndrome (ARDS) Adult respiratory distress syndrome (ARDS)

or renal failure often occurs or renal failure often occurs postresuscitationpostresuscitation

Symptoms may not appear for 24 hrsSymptoms may not appear for 24 hrs

Transport all submersion patientsTransport all submersion patients

Diving EmergenciesDiving Emergencies

IncidenceIncidence Medical emergencies caused by:Medical emergencies caused by:

Mechanical effects of pressureMechanical effects of pressure BarotraumaBarotrauma

Air embolismAir embolism Breathing of compressed airBreathing of compressed air

Decompression sicknessDecompression sickness Nitrogen narcosisNitrogen narcosis

Mechanical Effects of PressureMechanical Effects of Pressure Basic properties of gasesBasic properties of gases

Increased pressure dissolves gases Increased pressure dissolves gases into bloodinto blood

Oxygen metabolizes; nitrogen Oxygen metabolizes; nitrogen dissolvesdissolves

Boyle’s LawBoyle’s Law When pressure is doubled, volume of gas When pressure is doubled, volume of gas

is halvedis halved PV = KPV = K

P = PressureP = Pressure V = VolumeV = Volume K = ConstantK = Constant

Trapped gases expand as pressure Trapped gases expand as pressure decreasesdecreases

Dalton’s LawDalton’s Law Pressure from each gas in a mixture of Pressure from each gas in a mixture of

gases is the same as it would be if gases is the same as it would be if that gas alone occupied the same that gas alone occupied the same volumevolume

Pt Pt -- PO PO22 + PN + PN22 + Px + Px Pt = Total pressurePt = Total pressure POPO22 = Partial pressure of oxygen = Partial pressure of oxygen PNPN22 = Partial pressure of nitrogen = Partial pressure of nitrogen Px = Partial pressure of remaining gasesPx = Partial pressure of remaining gases

Henry’s LawHenry’s Law

At constant pressure, solubility of gas At constant pressure, solubility of gas in liquid is proportionate to partial in liquid is proportionate to partial pressure of gaspressure of gas

%X = Px/Pt x 100%X = Px/Pt x 100 %X = Amount of gas dissolved in liquid%X = Amount of gas dissolved in liquid Px = Partial pressure of gasPx = Partial pressure of gas Pt = Total atmospheric pressurePt = Total atmospheric pressure

Barotrauma of DescentBarotrauma of Descent””Squeeze”Squeeze”

PainPain Sensation of fullnessSensation of fullness HA, disorientationHA, disorientation VertigoVertigo NauseaNausea Bleeding from nose or earsBleeding from nose or ears

Pre-hospital carePre-hospital care SupportiveSupportive

Barotrauma of AscentBarotrauma of Ascent Reverse squeezeReverse squeeze Breath holding during ascentBreath holding during ascent POPSPOPS

Alveolar ruptureAlveolar rupture PneumomediastinumPneumomediastinum Subcutaneous emphysemaSubcutaneous emphysema Air embolismAir embolism

Administer oxygenAdminister oxygen

Transport for possible hyperbaric careTransport for possible hyperbaric care

Air EmbolismAir Embolism

Complication of pulmonary Complication of pulmonary barotraumabarotrauma Expanding air disrupts tissuesExpanding air disrupts tissues Air forced into circulatory systemAir forced into circulatory system Air passes through left side of heartAir passes through left side of heart Lodges in small arteriolesLodges in small arterioles Blocks distal circulationBlocks distal circulation

Air EmbolismAir Embolism Paralysis or sensory changeParalysis or sensory change AphasiaAphasia ConfusionConfusion BlindnessBlindness ConvulsionsConvulsions Loss of consciousnessLoss of consciousness


History of a recent diveHistory of a recent dive

Change in LOCChange in LOC

CVA-CVA-

ICPICP

MIMI

Air EmbolismAir Embolism——CareCare Maintain ABCsMaintain ABCs Remove wet clothing and keep warmRemove wet clothing and keep warm Oxygen, IV, EKGOxygen, IV, EKG Initially- place on left side trendelenberg Initially- place on left side trendelenberg

positionposition After 30-60 minutes, place supine to After 30-60 minutes, place supine to

prevent the worsening of cerebral prevent the worsening of cerebral edemaedema

Transport to hospital with hyperbaric Transport to hospital with hyperbaric chamberchamber

Decompression SicknessDecompression Sickness

Bends, dysbarism, caisson disease, Bends, dysbarism, caisson disease, and diver's paralysisand diver's paralysis

Multisystem disorderMultisystem disorder Nitrogen in compressed air converts Nitrogen in compressed air converts

from solution to gasfrom solution to gas Forms bubbles in tissues and bloodForms bubbles in tissues and blood


DyspneaDyspnea ItchItch RashRash Joint painJoint pain CrepitusCrepitus FatigueFatigue

VertigoVertigo ParesthesiasParesthesias ParalysisParalysis SeizuresSeizures UnconsciousnessUnconsciousness


Symptoms 12-36 hrs after diveSymptoms 12-36 hrs after dive Pre-hospital carePre-hospital care

Support vital functionsSupport vital functions High-concentration oxygenHigh-concentration oxygen Fluid resuscitationFluid resuscitation Rapid transport for recompressionRapid transport for recompression

Nitrogen NarcosisNitrogen Narcosis

““Rapture of the deep”Rapture of the deep”Nitrogen dissolved in bloodNitrogen dissolved in bloodHigh atmospheric pressureHigh atmospheric pressure

Impaired judgmentImpaired judgmentSlowed motor responseSlowed motor response

EuphoriaEuphoriaPotential memory lossPotential memory loss

Nitrogen NarcosisNitrogen Narcosis

Supportive careSupportive care

Assess for injuries Assess for injuries

TransportTransport

High-Altitude IllnessHigh-Altitude Illness

>>8000 ft above sea level8000 ft above sea level Reduced atmospheric pressureReduced atmospheric pressure Hypobaric hypoxiaHypobaric hypoxia Associated with:Associated with:

Mountain climbingMountain climbing Aircraft or glider flightAircraft or glider flight Hot-air balloonsHot-air balloons Low-pressure or vacuum chambersLow-pressure or vacuum chambers

High-Altitude IllnessHigh-Altitude Illness——PreventionPrevention

Gradual ascentGradual ascent Limit exertionLimit exertion Decrease sleeping at altitudeDecrease sleeping at altitude High CHO dietHigh CHO diet MedicationsMedications

ControversialControversial

Acute Mountain Sickness (AMS)Acute Mountain Sickness (AMS)

Rapid ascent of unacclimatized Rapid ascent of unacclimatized person to high altitudesperson to high altitudes 4-6 hrs after reaching high altitude4-6 hrs after reaching high altitude Maximal within 24-48 hrsMaximal within 24-48 hrs Abates on 3Abates on 3rdrd or 4 or 4thth day day Gradual acclimatizationGradual acclimatization

Acute Mountain Sickness (AMS)Acute Mountain Sickness (AMS) HeadacheHeadache Nausea, vomitingNausea, vomiting Dizziness, irritabilityDizziness, irritability Dyspnea on exertionDyspnea on exertion Tachycardia or bradycardiaTachycardia or bradycardia AtaxiaAtaxia AlteredAltered vomitingvomiting postural hypotensionpostural hypotension

Acute Mountain Sickness (AMS)Acute Mountain Sickness (AMS) Pre-hospitalPre-hospital

OxygenOxygen DescentDescent

HospitalHospital DiureticsDiuretics SteroidsSteroids Hyperbaric therapyHyperbaric therapy

High-Altitude Pulmonary Edema High-Altitude Pulmonary Edema (HAPE)(HAPE)

Increased pulmonary artery pressure Increased pulmonary artery pressure develops in response to hypoxiadevelops in response to hypoxia Leukotrienes releasedLeukotrienes released

Increase pulmonary arteriolar permeabilityIncrease pulmonary arteriolar permeability Leakage of fluid into extravascular spacesLeakage of fluid into extravascular spaces 24-72 hrs after reaching high altitudes24-72 hrs after reaching high altitudes Often preceded by exerciseOften preceded by exercise

HAPE Signs & SymptomsHAPE Signs & Symptoms HyperpneaHyperpnea Crackles, rhonchiCrackles, rhonchi TachycardiaTachycardia Hyperpnea (deep, rapid breathing)Hyperpnea (deep, rapid breathing) CyanosisCyanosis Immediate descent to a lower altitudeImmediate descent to a lower altitude Shortness of breath, coughShortness of breath, cough Weakness, lethargyWeakness, lethargy Crackles, rhonchiCrackles, rhonchi Decreased LOC as hypoxia sets inDecreased LOC as hypoxia sets in

High-Altitude Cerebral Edema High-Altitude Cerebral Edema (HACE)(HACE)

Severe acute high-altitude illnessSevere acute high-altitude illness Global cerebral signs with AMSGlobal cerebral signs with AMS Related to increased intracranial pressureRelated to increased intracranial pressure

From cerebral edema and swellingFrom cerebral edema and swelling Distinctions between AMS and HACE are blurredDistinctions between AMS and HACE are blurred

Mild AMS to unconsciousness with HACE Mild AMS to unconsciousness with HACE occurs within 12 hrsoccurs within 12 hrs

1-3 days of exposure to high altitudes1-3 days of exposure to high altitudes Same as AMS, headache to decreased LOCSame as AMS, headache to decreased LOC Hallucinations, stupor, coma, deathHallucinations, stupor, coma, death

HACEHACE Urgent management to preventUrgent management to prevent

ComaComa DeathDeath

Airway, ventilation, circulation Airway, ventilation, circulation supportsupport

Descent to lower altitudeDescent to lower altitude

ConclusionConclusion

Many emergencies result from exposure Many emergencies result from exposure to environmental elements. The to environmental elements. The

paramedic must be able to recognize paramedic must be able to recognize and manage these conditions by and manage these conditions by

understanding their causative factors understanding their causative factors and underlying pathophysiology.and underlying pathophysiology.

Questions?Questions?

Environmental Emergencies Paramedic

Documents

Transcript of Environmental Emergencies Paramedic