Internal Medicine

0521779407-14 CUNY1086/Karliner 0 521 77940 7 June 4, 2007 21:16

Menstrual Cycle Disorders for the Generalist Metabolic Acidosis 973

➣IM medroxyprogesterone acetate

➣Estrogen transdermal application during menses

■Catamenial seizures:

➣Epileptic seizures more common during menstruation

➣Seizure frequency increases at midcycle

➣Induced amenorrhea can decrease seizure frequency

■Premenstrual asthma:

➣30–40% of women with asthma have exacerbation with menses

➣Estradiol improves symptoms and PFTs

■Catamenial pneumothorax:

➣Recurrent pneumothoraces, at time of menses (due to endo-

metriosis)

➣IM medroxyprogesterone acetate

follow-up

n/a

complications and prognosis

■PMS resolves at menopause in most women but may recur on cyclic

HRT

METABOLIC ACIDOSIS

BIFF F. PALMER, MD

history & physical

■clinical setting helpful in determining etiology

■history of toxin ingestion, uncontrolled diabetes, cardiovascular col-

lapse, end-stage renal disease

■history of diarrhea, use of amphotericin B, toluene

tests

■check arterial blood gas to exclude chronic respiratory alkalosis

➣HCO3 <24 mEq/L with pH <7.40 confirms metabolic acidosis

➣HCO3 <24 mEq/L with pH >7.40 suggests chronic respiratory

alkalosis

■measure plasma anion gap: Na – (Cl+HCO3), normal value 8–16

■increased anion gap

➣calculate osmolar gap to screen for intoxication with methanol

or ethylene glycol

Calculated osmolity=serum Na (mEq/L)× 2 +glucose

(mg/dl)/18+BUN (mg/dl)/2.8