Tox: Calcium Channel Blocker OD

-verapamil is most potent, causes more deaths than all others combined
-sust release and sec gen dihyropyridines (nifedipine) extend duration of clinical tox -> delay in clinical manifestation

si/sx
-sinus bradycard with hypoten, cond disturb, complete sinus arrest with vent escape rhythms
-dec brain perf - dizziness, lethargy, agitation, conf, sz, hemiplegia
-gen weakness, metabolic acidosis with hyperglycemia, noncard pulm edema, hypo/hyperkalemia, hypercalcemia
-severe - slow jxnal rhythm, hypoxemia, lactic acidosis, dec lvef on echo

labs
-abg, lytes

Rx
-vitals, o2, monitor, iv
-activated charcoal 1g/kg
-whole-bowel irrigation for sust release preps
-hypoten
1) iv fluids then
2) calcium chloride 1g in 100cc ns through central line over 5 min, followed by 20-50mg/kg/h then
3) glucagon .1mg/kg mixed in NS, followed by infusion .1mg/kg/h
4) dopamine 1-20 mic/kg/h
5) amrinone 750 mic/kg IV then infusion 1-20 mic/kg/h
6) insulin 1.0 u/kg over 1 hr then .5 u/kg/h with admin of 20-30 g/h glc
7) 4-aminopyridine 10-50 mic/kg/h
8) cardiac pacing 45-50 beats per min
-acidosis maintain ph>7.20 with hypervent or bicarb

Dispo
-trivial ingestion, asx, nl vitals obs 6hr then clear; if sust release prep, longer