14.02.03 ICU notes

Kawasaki

• • Fever of ≥5 days' duration plus 4 of:

    • Bilateral nonsuppurative conjunctivitis

    • One or more changes of the mucous membranes of the upper respiratory tract

      • Pharyngeal injection, dry fissured lips, injected lips, "strawberry" tongue

    • One or more changes of the extremities

      • Peripheral erythema, peripheral edema, periungual desquamation, generalized desquamation

    • Polymorphous rash

      • Pimarily truncal

    • Cervical lymphadenopathy

      • >1.5 cm in diameter

  • Need echocardiogram to exclude coronary artery aneurysm

Maculopapular

• • Macules are small, flat discolored spots

  • Papules are small, raised bumps

Mefenamic acid overdose

• • Convulsions, nausea, emesis, haematemesis, bradypnea, coma

  • Renal failure

  • Onset of symptoms is usually between 30 minutes and 4 hours, but signs of renal failure may appear several days after an overdose

  • Lethal dose can be as low as 2.5 g

  • Conservative management; Can manage acidosis with bicarb

Sylvian fissure

• • AKA lateral sulcus

  • Divides the frontal lobe and parietal lobe above from the temporal lobe below

  • Longer in the left hemisphere in most people

  • Dot sign = MCA embolus

Methemoglobinemia

• • PathPhys

    • Higher than normal level of methemoglobin (metHb, i.e., ferric [Fe³⁺] rather than ferrous [Fe²⁺] haemoglobin) in the blood

    • Methemoglobin has a decreased ability to bind oxygen, but allosterically raises affinity for the other 3 ferrous haemoglobins

      • => Shifts dissociation curve to left => Tissue hypoxia

    • Elevated levels of methemoglobin in the blood are caused when the mechanisms that defend against oxidative stress within the red blood cell are overwhelmed

      • => Oxidation of ferrous iron

    • Can give the blood a bluish or chocolate-brown color

  • Causes

    • Congenital methemoglobinemia

      • Autosomal recessive - due to a deficiency of the enzyme diaphorase I (NADH methemoglobin reductase)

      • May also be seen in patients with abnormal hemoglobin variants such as hemoglobin M (HbM), or hemoglobin H (HbH)

        • Not amenable to reduction despite intact enzyme systems

      • Can also arise in patients with pyruvate kinase deficiency due to impaired production of NADH

      • Patients with Glucose-6-phosphate dehydrogenase (G6PD) deficiency may have impaired production of NADPH

    • Acquired

      • Exposure to exogenous oxidizing drugs and their metabolites (benzocaine, dapsone, nitrates)

        • e.g. Nitrates from farms in drinking water

      • Other classical drug causes:

        • Antibiotics (trimethoprim, sulfonamides, dapsone)

        • Local anesthetics (especially articaine and prilocaine)

        • Aniline dyes, metoclopramide, chlorates, bromates

  • Management

    • Supplemental oxygen and methylene blue 1% solution (10 mg/ml) 1 to 2 mg/kg slow IV

      • Restores the iron in hemoglobin to its normal (reduced) oxygen-carrying state

Notes

• • Erythromycin for gastric stasis

• AmBisome = Amphotericin B

  • IV antifungal

• Formoterol = LABA

• Clonidine

  • • Centrally acting α2 adrenergic agonist

    • For HTN. ADHA, anxiety/panic disorder, pain