Synthesis & Integration Unknown Case Infection & Immunity Elevated Temperature November 15 th, 2010 Amanda Kocoloski, OMS IV.

Synthesis & IntegrationUnknown Case

Synthesis & IntegrationUnknown Case

Infection & ImmunityElevated Temperature

November 15th, 2010

Amanda Kocoloski, OMS IV

Patient ProfilePatient Profile

Orvill R. Baker is a 58-year-old white male who exhibits a sudden elevation of body temperature during surgery

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SubjectiveSubjective CC/HxCC: Mr. Baker was undergoing radical

prostatectomy under general anesthesia for prostate cancer. He suddenly began to spike a fever, and developed muscle rigidity on the OR table just after initial abdominal incision was made. A sterile dressing was applied to his incision and he was brought to the recovery room. Chart review discloses that his prostate cancer was diagnosed by his primary care physician who noted a firm irregular nodule on his prostate during a routine physical exam. When biopsy confirmed the diagnosis, he was scheduled for surgery.

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DefinitionsDefinitions

Fever Regulated rise to a new “set point” of body temperature

Hyperthermia Body metabolic heat production or environmental

heat load exceeds normal heat loss capacity or when there is impaired heat loss

Why do we differentiate? Hyperthermia can be rapidly fatal and characteristically does not respond to antipyretics

Temperature Regulation

Temperature Regulation

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PO/AH

Differentials?Differentials?

Severe infection Thermoregulatory dysfunction Malignant hyperthermia Neuroleptic malignant syndrome

Serotonin syndrome Thyrotoxicosis Prolonged seizures Illegal drugs

Amphetamines, cocaine, PCP, LSD

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SubjectiveSubjective

Past Medical History: Prostate hypertrophy and doubling of PSA in one year to 8.0.

Injuries: Denies any past injuries. Immunizations: No immunizations beyond

childhood. Medications: Presently takes no medication on a

regular basis, including no OTC drugs. Allergies: Denies any significant drug or

environmental allergies. Surgical History: Has had no prior surgery. Hospitalizations: Never been hospitalized.

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Health Influencing Behaviors

Health Influencing Behaviors

Diet: The patient eats a “balanced diet” but follows no special dietary restrictions.

Exercise: Follows no particular exercise plan.

Sleep patterns: Sleeps approximately six hours nightly.

Caffeine use: Denies. Alcohol use: Denies. Nicotine use: Denies. Other substances: Denies.

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SubjectiveSubjective

Family Medical History: 3 siblings and 2 sons, all alive and well. Mother died unexpectedly during routine hysterectomy 30 years ago. Father living, age 82, with metastatic cancer of prostate.

Sexual History: No sexual activity for past 5 years due to erectile dysfunction.

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Social HistorySocial History

Family: Very supportive 58 year-old spouse whose only medical problem is DM Type II; 2 grown sons, healthy and living away from home.

Faith or spiritual beliefs: Attends a community church regularly.

Hobbies: Likes to travel and work around the house.

Occupation: Took early retirement from high school teaching last year.

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Review of SystemsReview of Systems

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System(s)

Findings

HEENT No headaches, blurry vision, difficulty swallowing

Face Symmetrical, no unusual facies

CV No chest pain or palpitations

Lungs No shortness of breath or cough

GI No diarrhea, constipation or abdominal pain

GU Complains of hesitancy, frequency, and difficulty starting stream

MSK No joint or muscle pain

Neuro No difficulties with movement, numbness or paresthesias

Endo No easy bruising, heat or cold intolerance

ObjectiveObjective

Vital Signs: T: 40.5 ˚C (105˚F) P: 150 bpm R: 14 resp/min (mechanical ventilation) BP:100/60 mmHg

General Appearance: Unconscious under general halothane anesthesia and succinylcholine muscle relaxation; mechanical ventilation via volume-cycled ventilator

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Where Was the Temperature Taken?

Where Was the Temperature Taken?

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Modified from Iaizzo PA, Kehler CH, Zink RS, et al: Thermal response in acute porcine malignant hyperthermia. Anesth Analg 82:803-809, 1996.)

Objective: Physical Exam

Objective: Physical Exam

Head, Eyes, Ears, Nose: Normocephalic; PERRL; EACs patent, TMs clear; nasal mucosa pink.

Throat: Mucosa dry; no pharyngeal inflammation or exudates. Remainder of exam hindered by presence of orotracheal tube.

Face: Symmetrical; no maxillary or frontal sinus tenderness.

Neck: Rigid and spastic; no palpable masses; no lymphadenopathy; thyroid is not palpable; trachea is midline and movable; no JVD; no carotid bruits.

Heart: Rapid, bounding rhythm; apical impulse palpated in left intercostal spaces four and five, lateral to midclavicular line; + S1 and S2; no S3 or S4; no murmurs, gallops or rubs.

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Objective: Physical Exam

Objective: Physical Exam

Lungs: (The patient is intubated and being ventilated with a volume-cycled respirator) clear to auscultation and percussion; full breath sounds bilaterally.

Breast: No masses, discharge or tenderness noted.

Abdomen: Slightly distended, firm; no masses or organomegaly; no fluid wave; no hepatojugular reflux; no inguinal lymphadenopathy; bowel sounds present in four quadrants; no bruits auscultated.

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Objective: Physical Exam

Objective: Physical Exam

Rectal: Deferred Structural: Deferred Extremities: Generalized muscular rigidity

and spasm; no cyanosis or clubbing; no edema or varicosities.

Skin: Hot, dry. Genital: Circumcised male; no scrotal

masses or penile discharge. Neurological: Generalized muscular

rigidity and spasm; unresponsive to any stimuli (patient under general anesthesia); mechanical ventilation.

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Diagnostic Studies?

Diagnostic Studies?

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Diagnostics- Urinalysis

Diagnostics- Urinalysis

Results

Normal

color brown amber-yellow

myoglobin positive

negative

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Diagnostics- ElectrolytesDiagnostics- Electrolytes

Result Normal

Sodium 140 mEq/L 135-147 mEq/L

Potassium 5.8 mEq/L 3.5-5.0 mEq/L

Chloride 100 mEq/L 95-105 mEq/L

Bicarbonate 18 mEq/L 24-40 mEq/L

BUN 26 mg/dL 8-25 mg/dL

Creatine kinase (CK, CPK)

5400 IU/mL 0-160 IU/mL

Creatinine 2.4 mg/dL 0.6-1.2 mg/dL

Phosphate 6.0 mg/dL 2.5-5 mg/dL

Uric Acid 8 mg/dL 2-7 mg/dL

Diagnostics- ElectrolytesDiagnostics- Electrolytes

Result Normal

Sodium 140 mEq/L 135-147 mEq/L

Potassium 5.8 mEq/L 3.5-5.0 mEq/L

Chloride 100 mEq/L 95-105 mEq/L

Bicarbonate 18 mEq/L 24-40 mEq/L

BUN 26 mg/dL 8-25 mg/dL

Creatine kinase (CK, CPK)

5400 IU/mL 0-160 IU/mL

Creatinine 2.4 mg/dL 0.6-1.2 mg/dL

Phosphate 6.0 mg/dL 2.5-5 mg/dL

Uric Acid 8 mg/dL 2-7 mg/dL

Diagnostics- Arterial Blood

Gases (ABGs)

Diagnostics- Arterial Blood

Gases (ABGs)

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Results Normal

PaO2 86 mmHg (80-100mmHg)

PaCO2 40 mmHg (35-45mmHg)

pH 7.22 (7.38-7.44)

HCO3 16 (21-30 mEq/L)

Diagnostics- Arterial Blood

Gases (ABGs)

Diagnostics- Arterial Blood

Gases (ABGs) Results Normal

PaO2 86 mmHg (80-100mmHg)

PaCO2 40 mmHg (35-45mmHg)

pH 7.22 (7.38-7.44)

HCO3 16 (21-30 mEq/L)

RhabdomyolysisRhabdomyolysis

Muscle necrosis results in systemic manifestations

Related to muscle injury or excessive muscle contraction

A syndrome of multiple etiologies Features include:

Myoglobinuria Renal insufficiency Markedly elevated creatine kinase (CK) levels

Frequently, multiorgan failure as a consequence of other complications of the trauma

Hyperkalemia in 10-40% of cases, due to release of K+ from injured skeletal muscle

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Cause of Elevated Temperature?

Cause of Elevated Temperature?

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AssessmentAssessment

Primary Diagnosis: Malignant hyperthermia Secondary Diagnoses:

RhabdomyolysisMyoglobinuriaHyperkalemiaTachycardiaPossible acute renal failure

Modifiable Risk Factors (MRF): None Non- Modifiable Risk Factors (NMRF): None

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Malignant hyperthermia

Malignant hyperthermia

Genetic mutation of ryanodine receptor type 1; autosomal

Disorder causes increased intracellular calcium; prevents Ca2+ reuptake after contraction and prevents relaxation

Usually asymptomatic until anesthesia

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Signs and SymptomsSigns and Symptoms Rigidity after induction of anesthesia

Sinus tachycardia or arrhythmias

Decrease in 02 saturation

Increase in PCO2

with ventilation Increase in temperature above 38.8 ˚C (101.8 ˚F)

Elevated temperature can be a late finding

Extreme acidosis Damage of skeletal muscle Rhabdomyolysis Myoglobinuria Hyperkalemia Acute renal failure

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CLINICAL FEATURESNEUROLEPTIC

MALIGNANT SYNDROMESEROTONIN SYNDROME

MALIGNANT HYPERTHERMIA

Triggering agent Neuroleptic Proserotonergic agent Succinylcholine or inhaled anesthetic

Onset Slow (hours to days) Fast (minutes to hours) Very fast to fast (minutes to hours)

Duration Long (days to weeks) Short (1–2 days) Short (1–3 days)

Agitation Sometimes Yes No

Confusion Yes Sometimes Unusual

Hyperactivity No Yes No

Bradykinesia/stupor Yes No Unusual

Myoclonus No Yes No

Shivering No Yes/sometimes No

Tremor Sometimes Yes No

Pupils Mid-sized Large Not specific

Rigidity Severe Sometimes Severe

Rigidity type Extrapyramidal (leadpipe) Pyramidal (clasp-knife) Generalized

Hyperpyrexia Yes Yes Severe

Tachypnea Yes Yes Yes

Tachycardia Yes Yes Yes (severe)

Leukocytosis Yes Uncommon Not typical

Elevated creatine phosphokinase

Severe Mild Severe

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PlanPlan

Treatment:Stop surgery and anesthesia ASAP Dantrolene

Inhibits the release of calcium from the sarcoplasmic reticulum, reducing actin-myosin contractile activity

Manage metabolic acidosisInitiate core and surface cooling

Avoid all future anesthesia using halothane and muscle relaxants

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PlanPlan

Diagnostic follow-up:Monitor for myoglobinuriaMonitor for renal failure (kidney

function studies)Monitor for cardiac dysrhythmias

Patient Education:Avoid all future anesthesia using

halothane and muscle relaxants

Cooling MeasuresCooling Measures

Alcohol sponges

Cold sponges Ice bags Ice-water enemas (burr)

Ice baths

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http://emedicine.medscape.com/article/149546-treatment

Quiz!Quiz!

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The elevated temperature in this

patient is most likely caused by

The elevated temperature in this

patient is most likely caused by

1 2 3 4

25% 25%25%25%

1.increased hypothalamic set point

2.endogenous pyrogens

3.excessive heat production

4.fever

What is the likely cause of the abnormal urinalysis and

serum potassium in this patient?

What is the likely cause of the abnormal urinalysis and

serum potassium in this patient?

1 2 3 4

25% 25%25%25% 1.Acidosis2.Excessive muscle

contraction and loss of sarcolemma integrity

3.Acute renal failure

4.Severely elevated temperature

The muscle rigidity in this patient is caused

by

The muscle rigidity in this patient is caused

by

1 2 3 4

25% 25%25%25%1. excessive motor

unit activation 2. excessive release

of calcium from the sarcoplasmic reticulum

3. halothane induction of calcium influx into muscle cells

4. hyperkalemia

What is the most likely reason why homeostatic mechanisms were unable to defend the thermal challenge presented

in the malignant hyperthermia case?

What is the most likely reason why homeostatic mechanisms were unable to defend the thermal challenge presented

in the malignant hyperthermia case?

1 2 3 4

25% 25%25%25%1. Body heat storage occurred

too rapidly2. General anesthetics

impaired the normal shivering response

3. General anesthetics impaired normal behavioral thermoregulatory responses

4. Surgery-induced dehydration changed the gain in the feedback control system

The elevated temperature in this patient can be

effectively controlled by

The elevated temperature in this patient can be

effectively controlled by

1 2 3 4

25% 25%25%25%1. dantrolene sodium

(inhibits Ca2+

release)2. high-dose aspirin

(inhibits PGE synthesis)

3. normalizing serum potassium

4. succinylcholine (neuromuscular blocking agent)