5 - hyperthermia - ppt kuliah

Hipertermia - Murdin AmitHipertermia - Murdin Amit 11

HyperthermiaHyperthermia

Murdin b AmitMurdin b Amit

( Bsc in Health Scn, Ba in BA (Hrm)( Bsc in Health Scn, Ba in BA (Hrm)

Ketua Unit Sains Perubatan U41Ketua Unit Sains Perubatan U41

Kolej Pembantu Perubatan SerembanKolej Pembantu Perubatan Seremban

Jalan Rasah, 70300 Seremban, Negeri SembilanJalan Rasah, 70300 Seremban, Negeri Sembilan


Objektif Pembelajaran:Objektif Pembelajaran:

Di akhir sesi pembelajaran pelajar boleh:Di akhir sesi pembelajaran pelajar boleh:

1. Menyatakan definisi hipertermia.1. Menyatakan definisi hipertermia.2. Menyatakan etiologi hipertermia.2. Menyatakan etiologi hipertermia.3. Menerangkan patofisiologi hipertermia.3. Menerangkan patofisiologi hipertermia.4. Menyatakan manifestasi klinikal hipertermia.4. Menyatakan manifestasi klinikal hipertermia.5. Menerangkan penyiasatan yang dilakukan.5. Menerangkan penyiasatan yang dilakukan.6. Menerangkan diagnosa perbezaan 6. Menerangkan diagnosa perbezaan hipertermia.hipertermia.7. Menyenaraikan komplikasi hipertermia.7. Menyenaraikan komplikasi hipertermia.8. Menerangkan pengendalian hipertermia.8. Menerangkan pengendalian hipertermia.9. Menerangkan pendidikan kesihatan yang 9. Menerangkan pendidikan kesihatan yang perlu dilakukanperlu dilakukan


1. Definisis hipertermia1. Definisis hipertermia Suhu badan yang terlalu tinggi (kira-kira 41°C atau lebih) Suhu badan yang terlalu tinggi (kira-kira 41°C atau lebih)

105°F - 109°F105°F - 109°F Badan tidak berupaya menyeimbangkan suhu.Badan tidak berupaya menyeimbangkan suhu. Boleh mengancam nyawa.Boleh mengancam nyawa. Orang tua atau orang muda lebih cendorong kena.Orang tua atau orang muda lebih cendorong kena.

Elevation of core body temperature above the normal range Elevation of core body temperature above the normal range of 36ºC to 37.5ºC due to failure of thermoregulationof 36ºC to 37.5ºC due to failure of thermoregulation

Hyperthermia: thermoregulation defect without change of Hyperthermia: thermoregulation defect without change of set pointset point

Hyperthermia is Hyperthermia is notnot synonymous with the more common sign of synonymous with the more common sign of fever, which is induced by fever, which is induced by cytokine activationcytokine activation during during inflammationinflammation, and regulated at the level of the , and regulated at the level of the hypothalamushypothalamus


ThermoregulationThermoregulation

ColdBehav ioura l

Cutaneou s vasoco nstrictio nShiverin g, non-s hiverin g

W armBehav ioura l

Cutaneo us vas odilatio nSweating ,Pantin g

Efferent Responses

Preoptic nucleiAnterior Hypothalam us

Thermal Receptorscold and warmS k in and v ice ral


Controlled by the hypothalamus Controlled by the hypothalamus (preoptic hypothalamus)(preoptic hypothalamus) (post hypothalamus)(post hypothalamus)

Monitoring body temperatureMonitoring body temperature1.- peripheral warmth / cold receptors-peripheral 1.- peripheral warmth / cold receptors-peripheral

nervenerve2.-blood temperature of the regions2.-blood temperature of the regions

The metabolic rate of humans consistently The metabolic rate of humans consistently produces more heat than is necessary to produces more heat than is necessary to maintain the core body temp. of 37maintain the core body temp. of 37°°CC

Body temperature is controled by heat Body temperature is controled by heat dissipation from skin and lungs.dissipation from skin and lungs.


2. Menyatakan etiologi hipertermia.2. Menyatakan etiologi hipertermia.

Heat stroke sindrom yang disebabkan oleh “over-Heat stroke sindrom yang disebabkan oleh “over-heating” badan oleh faktor :heating” badan oleh faktor :

suhu persekitaransuhu persekitaran humidity (iklim panas) humidity (iklim panas) gangguan badan untuk berpeluhgangguan badan untuk berpeluh gangguan yang disebabkan oleh dadah / ubatgangguan yang disebabkan oleh dadah / ubat

““Unacclimatised”.Unacclimatised”. Usia tua atau terlalu muda.Usia tua atau terlalu muda.

Faktor Penggalak:Faktor Penggalak:

Alkohol, Alkohol, Dehidrasi, Dehidrasi, Kegemukan, Kegemukan, Berpenyakit (endokrin, kardiak dan neurologikal).Berpenyakit (endokrin, kardiak dan neurologikal).


Etiologi Etiologi

Drug-induced hyperthermiaDrug-induced hyperthermiaMonoamine oxidase (MAO) inhibitorsMonoamine oxidase (MAO) inhibitorsTricyclic antidepressants amphetaminesTricyclic antidepressants amphetaminesPhencyclidine(PCP)Phencyclidine(PCP)Lysergic acid diethylamide (LSD)Lysergic acid diethylamide (LSD)CocaineCocaine


Etiologi Etiologi

Conditions include:Conditions include:Cardiovascular diseaseCardiovascular diseaseNeurologic or psychiatric disordersNeurologic or psychiatric disordersObesityObesityAnhidrosisAnhidrosisExtremes of ageExtremes of ageAnticholinergic agents or diuretics Anticholinergic agents or diuretics


Etiologi Etiologi

The most important causes of severe The most important causes of severe hyperthermia (greater than 40ºC or hyperthermia (greater than 40ºC or 104ºF) caused by failure of 104ºF) caused by failure of thermoregulation are:thermoregulation are:Heat strokeHeat strokeNeuroleptic malignant syndromeNeuroleptic malignant syndromeMalignant hyperthermia Malignant hyperthermia


3. Menerangkan patofisiologi hipertermia.3. Menerangkan patofisiologi hipertermia.

Faktor penyebabFaktor penyebab Gangguan pada sel membran otot.Gangguan pada sel membran otot. Berlaku akibat agen seperti :Berlaku akibat agen seperti :

Halogen anaesthetic agents.Halogen anaesthetic agents. Succinylcholine.Succinylcholine.

Agen - meningkatkan kadar myoplasmic Ca (2+) , ini Agen - meningkatkan kadar myoplasmic Ca (2+) , ini menyebabkan meningkatnya suhu badan dan otot menjadi menyebabkan meningkatnya suhu badan dan otot menjadi kaku. kaku.

Peripheral and body core receptors – senses changePeripheral and body core receptors – senses change Hypothalamic thermoregulatory center – integrates & initiates:Hypothalamic thermoregulatory center – integrates & initiates: Shivering, non-shivering thermogenesis, vasoconstrictionShivering, non-shivering thermogenesis, vasoconstriction


PathophysiologyPathophysiology

Once hypothalamic setpoint is raised, neurons Once hypothalamic setpoint is raised, neurons in the vasomotor center are activated in the vasomotor center are activated (vasoconstriction)(vasoconstriction)

Vasoconstriction first noted in hands and feet Vasoconstriction first noted in hands and feet (“cold hands and feet”)(“cold hands and feet”)

Shivering is not required if heat conservation Shivering is not required if heat conservation mechanisms sufficently raise blood tempmechanisms sufficently raise blood temp



Pathophysiology of central hyperthermia:Pathophysiology of central hyperthermia:Thermoregulator: postral hypothalamic/ Thermoregulator: postral hypothalamic/

preoptic regionpreoptic regionInjury of other brain tissue release Injury of other brain tissue release

prostaglandin E2prostaglandin E2However, NSAIDs doesn’t always have effect However, NSAIDs doesn’t always have effect

to central hyperthermiato central hyperthermia



Acute hydrocephalus and central Acute hydrocephalus and central hyperthermia:hyperthermia:Hypothalamic compression to induce Hypothalamic compression to induce

release of hypothalamic neuropeptiderelease of hypothalamic neuropeptideaxonal stretch could inhibit the release axonal stretch could inhibit the release

of other agents, such as dopamineof other agents, such as dopaminedopamine causes a fall in body dopamine causes a fall in body

temperaturetemperature



Body temperature is maintained within a Body temperature is maintained within a narrow range by balancing heat load with heat narrow range by balancing heat load with heat dissipation.dissipation.

Body's heat load results from both metabolic Body's heat load results from both metabolic processes and absorption of heat from the processes and absorption of heat from the environmentenvironment

As core temperature rises, the As core temperature rises, the preoptic preoptic nucleusnucleus of the of the anterior hypothalamusanterior hypothalamus stimulates stimulates efferent fibers of the ANSefferent fibers of the ANS to to produce produce sweatingsweating and cutaneous and cutaneous vasodilationvasodilation..



Evaporation is the principal mechanism of heat Evaporation is the principal mechanism of heat loss in a hot environment, but this becomes loss in a hot environment, but this becomes ineffectiveineffective above a relative humidity of 75% above a relative humidity of 75%

Other methods of heat dissipationOther methods of heat dissipation Radiation- emission of infrared electromagnetic energyRadiation- emission of infrared electromagnetic energy Conduction- direct transfer of heat to an adjacent, cooler Conduction- direct transfer of heat to an adjacent, cooler

objectobject Convection-direct transfer of heat to convective air Convection-direct transfer of heat to convective air

currentscurrents These methods cannot efficiently transfer heat These methods cannot efficiently transfer heat

when when environmental temperature exceeds skin environmental temperature exceeds skin temperature.temperature.



Temperature elevation Temperature elevation ↑ O2 ↑ O2 consumption and metabolic rate consumption and metabolic rate hyperpnea and tachycardiahyperpnea and tachycardia

Above 42ºC (108ºF), oxidative Above 42ºC (108ºF), oxidative phosphorylation becomes uncoupled, and phosphorylation becomes uncoupled, and a variety of enzymes cease to function.a variety of enzymes cease to function.

Hepatocytes, vascular endothelium, and Hepatocytes, vascular endothelium, and neural tissueneural tissue are are most sensitivemost sensitive to these to these effects, but all organs may be involved.effects, but all organs may be involved.

As a result, these patients are at risk of As a result, these patients are at risk of multiorgan system failure.multiorgan system failure.


4. Menyatakan manifestasi klinikal hipertermia.4. Menyatakan manifestasi klinikal hipertermia.

berlaku secara dramatic – tiada warningberlaku secara dramatic – tiada warning pesakit nampak normal – tiada dehidarasi, tetapi suhu pesakit nampak normal – tiada dehidarasi, tetapi suhu

badan tinggi dan tiada berpeluhbadan tinggi dan tiada berpeluh sakit kepalasakit kepala mual dan muntahmual dan muntah tanda-tanda neurologikal seperti kekeliruan, meracau, dan tanda-tanda neurologikal seperti kekeliruan, meracau, dan

ketidaksedaran diriketidaksedaran diri

Bercirikan: Bercirikan: Suhu rektum diantara 105–106ºF atau lebih, Suhu rektum diantara 105–106ºF atau lebih, Hangat, kulit kering, Hangat, kulit kering, Gangguan pada sensorium, Gangguan pada sensorium, Takikardia, Takikardia, Hipotensi, and Hipotensi, and Hiperventilasi. Hiperventilasi.


Symptoms and signsSymptoms and signs

Symptoms and signs (Frequency):Symptoms and signs (Frequency):Hyperthermia 25 %Hyperthermia 25 %Diaphoresis 18 %Diaphoresis 18 %Hypertension 26 %Hypertension 26 %Tachypnea 18 %Tachypnea 18 %Rigidity 27 %Rigidity 27 %


5. Menerangkan penyiasatan yang dilakukan.5. Menerangkan penyiasatan yang dilakukan.

FBCFBC BUSEBUSE ECGECG


Menerangkan penyiasatan yang Menerangkan penyiasatan yang dilakukan.dilakukan.

Get a rectal temperature; abnormal VS include sinus Get a rectal temperature; abnormal VS include sinus tachycardia, tachypnea, widened pulse pressure, tachycardia, tachypnea, widened pulse pressure, hypotension hypotension

CXR may demonstrate pulmonary edemaCXR may demonstrate pulmonary edema EKG may reveal dysrhythmias, conduction disturbances, EKG may reveal dysrhythmias, conduction disturbances,

nonspecific ST-T wave changes, or heat-related myocardial nonspecific ST-T wave changes, or heat-related myocardial ischemia or infarctionischemia or infarction

Labs: CBC CCP, Coagulation Studies, creatine kinase, and Labs: CBC CCP, Coagulation Studies, creatine kinase, and check for hyperphosphatemia, myoglobinuria check for hyperphosphatemia, myoglobinuria

Myoglobinuria should be suspected in a patient who has a Myoglobinuria should be suspected in a patient who has a brown urine supernatant that is heme-positive, and clear brown urine supernatant that is heme-positive, and clear plasma. plasma.

Toxicologic screening may be indicated if a medication Toxicologic screening may be indicated if a medication effect is suspected. effect is suspected.

Head CT and lumbar puncture if CNS etiologies suspected Head CT and lumbar puncture if CNS etiologies suspected


Menerangkan penyiasatan yang Menerangkan penyiasatan yang dilakukan.dilakukan.


6. Menerangkan diagnosa perbezaan hipertermia.6. Menerangkan diagnosa perbezaan hipertermia.

1.1. Suhu badan lebih daripada 41CSuhu badan lebih daripada 41C


7. Menyenaraikan komplikasi hipertermia.7. Menyenaraikan komplikasi hipertermia.

RenjatanRenjatan Edema serebralEdema serebral Complications include:Complications include:

ARDSARDSDIVCDIVCRenal or hepatic failureRenal or hepatic failureHypoglycemiaHypoglycemiaRhabdomyolysisRhabdomyolysisSeizures Seizures


8. Menerangkan pengendalian hipertermia.8. Menerangkan pengendalian hipertermia.

pindahakan pesakit ke tempat yang terlindungpindahakan pesakit ke tempat yang terlindung tanggalkan pakaiantanggalkan pakaian kulit pesakit sentiasa dibasahkan dengan air (bukan sejuk)kulit pesakit sentiasa dibasahkan dengan air (bukan sejuk) pasangkan kipas untuk pesakitpasangkan kipas untuk pesakit kekalkan airway, dan berikan oksigenkekalkan airway, dan berikan oksigen Langkah pencegahanLangkah pencegahan:: AcclimatisationAcclimatisation Pakaian yang sesuai untuk keadaanPakaian yang sesuai untuk keadaan Minum air dengan cukupMinum air dengan cukup Pengambilan garam dengan cukupPengambilan garam dengan cukup Jangan terlalu terdedah kepada keadaan yang terlalu panasJangan terlalu terdedah kepada keadaan yang terlalu panas


Menerangkan pengendalian hipertermiaMenerangkan pengendalian hipertermia


Thermoregulation: Prevention of OverheatingThermoregulation: Prevention of OverheatingThermoregulation: Prevention of OverheatingThermoregulation: Prevention of Overheating



CVPCVP monitoring is useful for assessing volume status monitoring is useful for assessing volume status and determining the need for fluid resuscitation and determining the need for fluid resuscitation

Alpha-adrenergic agonists should be Alpha-adrenergic agonists should be avoidedavoided, since , since the resultant vasoconstriction decreases heat the resultant vasoconstriction decreases heat dissipation. dissipation.

Continuous core temperature monitoringContinuous core temperature monitoring with a rectal with a rectal or esophageal probe is mandatory, and cooling or esophageal probe is mandatory, and cooling measures should be stopped once a temperature of measures should be stopped once a temperature of 39.5ºC (103ºF) has been achieved in order to reduce 39.5ºC (103ºF) has been achieved in order to reduce the risk of iatrogenic hypothermiathe risk of iatrogenic hypothermia

In the case of malignant hyperthermia, the presumed In the case of malignant hyperthermia, the presumed causative agent must be discontinued immediatelycausative agent must be discontinued immediately



Cooling measuresCooling measures Naked patient is sprayed with a mist of lukewarm Naked patient is sprayed with a mist of lukewarm

water while air is circulated with large fans. Shivering water while air is circulated with large fans. Shivering may be suppressed with intravenous may be suppressed with intravenous benzodiazepines such as diazepam (5 mg IV) or benzodiazepines such as diazepam (5 mg IV) or lorazepam (1-2 mg IV).lorazepam (1-2 mg IV).

Immersing the patient in ice water is the most Immersing the patient in ice water is the most effective method of rapid cooling but complicates effective method of rapid cooling but complicates monitoring and accessmonitoring and access

Applying ice packs to the axillae, neck, and groin is Applying ice packs to the axillae, neck, and groin is effective, but is poorly tolerated in the awake patienteffective, but is poorly tolerated in the awake patient



Cold peritoneal lavage results in rapid cooling, but it Cold peritoneal lavage results in rapid cooling, but it is an invasive technique that is contraindicated in is an invasive technique that is contraindicated in pregnant patients or those with previous abdominal pregnant patients or those with previous abdominal surgery.surgery.

Cold oxygen, cold gastric lavage, cooling blankets, Cold oxygen, cold gastric lavage, cooling blankets, and cold intravenous fluids may be helpful adjuncts.and cold intravenous fluids may be helpful adjuncts.

There is no role for antipyretic agents such as There is no role for antipyretic agents such as acetaminophen or ASA in the management of heat acetaminophen or ASA in the management of heat stroke, since the underlying mechanism does not stroke, since the underlying mechanism does not involve a change in the hypothalamic set-pointinvolve a change in the hypothalamic set-point

Alcohol sponge baths should be avoided because Alcohol sponge baths should be avoided because large amounts of the drug may be absorbed through large amounts of the drug may be absorbed through dilated cutaneous vessels and produce toxicitydilated cutaneous vessels and produce toxicity


9. Menerangkan pendidikan kesihatan yang perlu 9. Menerangkan pendidikan kesihatan yang perlu dilakukandilakukan

Jangan mendedahkan diriJangan mendedahkan diriMinum air dengan cukupMinum air dengan cukupContinuous core temperature Continuous core temperature

monitoringmonitoring

5 - hyperthermia - ppt kuliah

Documents