In the ED, their vitals/exam are as above. The differential for AKI includes 1) pre-renal etiologies (decreased circulating volume: dehydration from poor PO intake/diarrhea/vomiting/diuresis, sepsis, cardiorenal syndrome, hepatorenal syndrome, bleeding, salt wasting; afferent dysfunction: constriction from NSAIDS/contrast OR dilation from ACEi, ARB; large vessel disease: renal artery stenosis, thromboembolic), 2) intra-renal etiologies (tubular/interstitial: ATN, AIN, cast nephropathy from multiply myeloma, urate nephropathy from TLS, crystalline nephropathy from acyclovir; small vessel: vasculitides, MAHA, TTP/HUS, scleroderma, atheroembolic disease, malignant hypertension; large vessel: renal infarction secondary to aortic dissection, systemic thromboembolism, renal artery aneurysm, acute renal vein thrombosis; glomerular: ANCA such as GPA, EGPA, MPA, Anti-GBM such as Goodpasture’s, Immune complex mediated such as PSGN, MPGN, Fibrillary, IgA, Endocarditis, SLE, Cryo, HSP), 3) post-renal etiologies (BPH, bladder neck stricture, kidney stones, malignancy, anticholinergic medications, RP bleed, RP fibrosis). On my assessment, this patient’s presentation is most consistent with ***.
– Labs/Tests: Lactate, CBC, CMP (BUN:Cr of >20 argues in favor of pre-renal etiology, 10-20 argues in favor of post-renal etiology, <10 argues in favor of intrarenal etiology), Serum osms, CK, Serum Tox, Consider uric acid/LDH/ionized calcium if cancer patient, UA/USed, UTox, Urine lytes (K, Na, Cl, Cr, Osms, Urea, Eosinophils), Urine protein, Urine culture, Recheck BMP after IVF bolus, Spin urine as inpatient - Imaging: Renal US with dopplers as inpatient, Bladder scan w/ PVR (>100 is abnormal) if indicated as inpatient
– Treatments: IVF, renally dose all medications, avoid nephrotoxic agents, foley as indicated, pain control as indicated, antiemetics as indicated, consider bicarb infusion at 100cc/hr if bicarb <10 - Consults: Nephrology consult as inpatient - Dispo: Likely admission