2022-05-13-pressors.md (1410B)
1 # pressors 2 3 4 MAP = SVR * CO 5 6 CO = HR * SV 7 8 # receptors 9 10 alpha1, beta1, beta2 11 12 alpha1 = vessel walls, contracts 13 14 beta1 = contractility 15 16 beta2 = vasodilation, bronchodilation 17 18 vasopressin/ADH = V1 (vasoconstriction in the periphery), V2 (in kidneys) 19 20 AngII = inc aldosterone, peripheral vasoconstriction. 21 22 # drugs 23 24 epi = +++alpha1, +++beta1, ++beta2. 25 Useful during codes, anaphylaxis (bronchodilation), third(ish)-line in sepsis. 26 27 norepi = ++alpha1, ++beta1, no beta2. 28 Go-to pressor. 29 30 phenylephrine = +++alpha1, no beta1, no beta2. 31 Useful pressor if tachyarrhythmia and not in cardiogenic shock. 32 33 dobutamine = no alpha1, ++beta1, +beta2. 34 Used in cardiogenic shock (+chronotropy, +inotropy), pHTN. 35 36 dopamine = not really used any more 37 38 vasopressin (ADH) = mostly looking for V1 effects 39 40 AngII = Used in septic shock. 41 Very pt-dependent, 42 "super-responders" (~10%) can sometimes come off all other pressors, 43 most folks don't respond much. 44 C/i in heart failure. 45 Increases clotting (cannot use if cannot use DVT ppx). 46 47 also think about: 48 stress-dose steroids (little downside, cortisol testing is useless in critically ill pts), 49 acidosis (do they need bicarb drip/post-replacement bicarb?) 50 51 52 # access 53 54 Pressors via PIVs are usually fine. 55 No actual dosage cutoff, 56 some institutions will create cutoffs 57 but there's no data for that. 58 59 Extravasation rate ~3/1000 in one retrospective study of ~14,000 pts.