ACE 18A 2021

Kawasaki Disease

• Previously known as mucocutaneous lymp node syndrome
• leading cause of acquired cardiac disease in kids
• vasculitis of medium sized vessels, mainly coronaries
• coronary artery aneurysms develop in 25% of cases
• Rx with immunotherapy and anti-inflamatories (aspirin)
• classic clinical presentation:
  • high fever
  • nonexudative conjunctival redness
  • cervical lymphadenopathy
  • erythema of palms and soles
  • edema of hands and feet
  • maculopapular rash
  • strawberry tongue

Treatment of Bronchospasm

• propofol and IA are direct bronchodilators
• B2 agonist such as albuterol

Superior Hypogastric Plexus

• injury can lead to retrograde ejaculation and infertility
• possible with anterior approaches to the lumbosacral spine

Pulmonary Hypertension

• any pulmonary pressure over 25mmHg
• treatment mechanisms and examples

Mechanism	Example	Adverse Effects
Direct relaxation of smooth muscle	Nitric Oxide	Toxicity from production of NO2 and methemoglobin
Prostocyclin receptor stimulation	Iloprost	Systemic vascular effects
Prostocyclin receptor stimulation	Epoprostenol	Flushing and hypotension
Calcium channel blocker	Nifedipine	Hypotension
Endothelin receptor blocker	Bosentan	Liver dysfunction
Phosphodiesterase-5 inhibitor	Sildenafil	Few
Angiotensin receptor blocker	Ramipril	Hypotension

Bayonet Effect

• Ultrasound effect that produces appearance of a bent medal needle due to the slightly different speeds with which ultrasound beams travels through muscle vs adipose tissues.

Oculocardiac Reflex

• Afferent pathway:
  1. Long and short ciliary nerve
  2. Ciliary ganglion
  3. Opthalmic branch of trigeminal nerve (CN V)
  4. Gasserian (trigeminal) ganglion
  5. Main sensory nucleus of trigeminal nerve (in brainstem)
• Efferent pathway:
  1. Vagus nerve (CN X)
  2. Heart (release of ACh at SA node)
• Treatment:
  • stop stimulus
  • anticholinergic (glycopyrrolate or atropine)
• Makes worse:
  • hypercarbia
  • hypoxia

Respiratory Pressure Definitions

Pressure	Definition	Notes
Peak airway pressure	Maximum value of the airway pressure at airway opening	Influenced by airway resistance and lung/chest wall compliance. Increased with airway obstruction or decreased complaince issues
Plateau pressure	Pressure that is recorded within the airway when there is NO airflow (static compliance)	Only increases with worsening compliance. Good indicator of alveolar pressure. Obstruction has no effect (because no airflow)
Mean airway pressure	Average airway pressure over the total ventilatory cycle	This pressure affects heart-lung interactions

Myocardial Ischemia Treatment

• oxygen
• aspirin
• benzodiazepine
• nitroglycerin
• Avoid:
  • Sodium nitroprusside (hypotension and reflex tachycardia)
  • Beta-blocker (leaves alpha agonism available to cause vasocoronary constriction)

Immune System Response

• Plasma cells are differentiated B lymphcytes (B Cells) capable of secreting immunoglobulins (antibodies)
• In response to antigen exposure, T lymphocytes activate B cell to produce antibodies
• 5 types: IgA, IgD, IgE, IgG, and IgM
• IgM and IgG are found in blood, lymph, and tissues
• IgM comes first, followed by higher number of IgG
• On second exposure, IgG comes faster following IgM again, and it peaks higher and stay longer
• IgA found in mucous membrances and helps precent colonization
• IgE associated with allergic reactions by binding to allergens and mast cells to release histamine
• IgD rarely a/w multiple myeloma

Hypertension Treatment in Pregnancy

• avoid ACE-I and ARB as they can cause:
  • fetal renal failure
  • oligohydramnios
  • craniofacial abnormalities
  • pulmonary hypoplasia
• treatment of choice: alpha-methyldopa
• Beta blockers may cause neonatal hypoglycemia by increasing secretion of insulin
• Mixed alpha/beta blockers (labetalol) okay
• CCB have a theoretical risk of decreasing uterine contraction and prolonging labor

SSEP

• somatosensory-evoked potentials
• objective measure of ascending sensory pathway function

Drug	Mechanism	Effect on SSEPs
Ketamine	NMDA blocker (N-methyl-D-aspartate)	Increases
Dexmedetomidine	alpha-2 agonist	Decreases
Propofol	Enhances GABA-induced chloride current / GABA agonist	Decreases
Xenon	NMDA blocker (N-methyl-D-aspartate)	Decreases
Nitrous Oxide	NMDA blocker (N-methyl-D-aspartate)	Decreases

HCM and SAM

• HCM = hypertrophic cardiomyopathy
• SAM = systolic anterior motion (of the mitral valve)
• LVOTO = left ventricular outflow tract obstruction
• Components of HCM
  1. left ventricular hypertrophy
  2. disorganized myocardial cell patterns
  3. myocardial microvascular abnormalities
  4. LVOTO
• 3 grades of HCM:
  1. Obstructive = outflow gradient > 30 mmHg at rest
  2. Labile obstruction = outflow gradient of > 30 mmHg only with physiologic stimulation
  3. Nonobstructive = outflow gradient < 30 mmHg
• SAM mimics the clinical presentation of aortic stenosis
• SAM will often results in MV regurg and elevated left atrial pressures

Adrenal Gland

Tissue Area	Hormone Released	Example	Function
Zona glomerulosa	Mineralocorticoids	Aldosterone	Regulates mineral balance (Na retention)
Zona fasciculata	Glucocorticoids	Cortisol, Cortisone	Regulates glucose metabolism
Zona reticularis	Androgens	Dehydroepiandrosterone	Stimulates masculinization
Adrenal medulla	Stress hormones	Epi, Norepi	Stimulates sympathetic ANS

• Feedback loop:
  1. Hypothalamus –> CRH (corticotropin-releasing hormone)
  2. Pituitary –> ACTH (adrenocorticotropic hormone)
  3. Adrenal cortex –> cortisol
• Addison’s disease:
  • primary adrenal insufficiency
  • both mineralocorticoid and glucocorticoid production is suppressed
• Secondary adrenal insufficiency:
  • only glucocorticoid production is suppressed
• Surgical administration of stress dose steroids is targeting secondary adrenal insufficiency
• Dexamethasone has only glucocorticoid activity with no mineralocorticoid activity

Kussmaul Sign

• a significant increase in central pressure (as evidence by jugular venous distention) that occurs with inspiration

Neonatal Jaundice

• Physiologic jaundice: transient increase in indirect bilirubin in first 12-48 hours after birth
• Pathologice jaundice: increase in total bilirubin (>12) and direct bilirubin (>2) within 36 hours and lasts beyond 10 days
• Breast milk jaundice: unclear etiology, occurs on day 4-7 after birth

End Stage Liver Failure

• Symptoms:
  • hyperdynamic syndrome
  • high cardiac output
  • increased heart rate
  • increased total blood volume
  • reduced systemic vascular resistance
  • low or normal blood pressure
  • increased venous oxygen content
  • prolonged QT
• peripheral and splanchnic vasodilation is due to increased NO production in cirrhosis
• danger is undiagnosed cirrhotic cardiomyopathy - with stress comes increase in preload, leading to cardiac failure

TIPS

• Transjugular intrahepatic portosystemic shunt (TIPS)
• Connects the vein which brings blood from your gastrointestinal tract and the vein from your liver to the right part of your heart
• Connects portal vein to hepatic vein to reduce flow to liver

APGAR

-0, 1, 2 to each of the following:

• Appearance
• Pulse
• Grimace
• Activity
• Respiration

Risks of Peripheral Nerve Injury

• male sex
• obesity
• preexisting neurologic symptoms
• DM
• peripheral vascular disease
• alcohol dependence
• tobacco use
• arthritis

Conditions that decrease nicotinic acetylcholine receptors

• myasthenia gravis
• anticholinesterase poisoning
• organophosphate poisoning

Metformin

• Mechanism: reduction of gluconeogenesis, limiting the conversion of lactate and glycerol to glucose
• Side Effect: severe lactic acidosis
• hold while patient NPO
• treatment is withhold medication and hydrate

Most common cause of pregnancy-related deaths?

• cardiovascular disease
• 1/3 of all deaths

Magnesium

• mechanism: NMDA receptor blocker
• NMDA = N-methyl-D-aspartate
• When used:
  • preexlampsia
  • torsades de pointes (polymorphic V-tach)
  • pheochromocytoma
• Side effects:
  • hypotension
  • respiratory depression
  • muscle weakness
  • widened QRS duration
  • CNS toxicity

Tocolytic Treatments

• tocolysis: labor suppression
• only safe for 48 hours of use (time for mom to receive steroids for neonatal lungs)

Drug Class	Examples	Notes
Calcium channel blockers	Nifedipine	most commonly used, causes hypotention
Cyclooxygenase inhibitors	Indomethacin, ketorolac	inhibits synthesis of prostaglandins from arachidonic acid
Beta-adrenergic receptor agonist	Terbutaline	selective for B2, pulmonary edema most serious adverse effect
Magnesium sulfate	Magnesium	Extracellular Mg competes with Ca at motor endplate