Severe metformin intoxication treated with prolonged haemodialyses and plasma exchange

Abstract

For the maximum elimination of metformin, extended haemodialysis is required and the treatment of the accompanying metabolic acidosis with bicarbonate is important for the effectiveness of the treatment. Patients benefit much more from the treatment of combined haemodialysis with plasma exchange.

Extracorporeal Treatment for Metformin Poisoning

“…Because metformin concentrations may increase or "rebound" after ECTR (i.e., redistribute from deeper compartments into the intravascular space), treatment of insufficient duration may result in a marked resurgence of lactic acidosis (66,78,80,83,84,99,116,117,137,140,144,158,169,171,182,189,203,205). Deaths have been reported when ECTR was stopped too early, despite an initial improvement (78,137,142,169).…”

“…Because metformin is not bound to plasma proteins, hemoperfusion (117,233), liver assist devices, or plasma exchange (203) do not offer any advantages over hemodialysis or CRRT, and they also do not effectively correct acid-base abnormalities (234). Because metformin is not bound to plasma proteins, hemoperfusion (117,233), liver assist devices, or plasma exchange (203) do not offer any advantages over hemodialysis or CRRT, and they also do not effectively correct acid-base abnormalities (234).…”

Medications in Patients Treated With Therapeutic Plasma Exchange: Prescription Dosage, Timing, and Drug Overdose

“…Despite the above PK tenets, the majority of reports describing a possible extractive effect of TPE on drugs only assessed serum concentration. Notable examples are: methotrexate (58) vincristine (59,60), amlodipine (15), diltiazem (61), verapamil (16,31,62–64), propranolol (65), dalteparin (44), dapsone (66), metformin (67), ampicillin (47), chloramphenicol (68), carbamazepine (69,70), theophylline (71,72), and amitriptyline (16). Indeed, most reports examining the amount of drug in the plasmapheresate showed a lack of TPE influence on drug removal (10,13).…”

Metformin-Associated Lactic Acidosis following Intentional Overdose Successfully Treated with Tris-Hydroxymethyl Aminomethane and Renal Replacement Therapy

“…The role of RRT appears to be in the correction of the acidosis as opposed to the clearance of metformin, although some limited clearance can occur [20, 23]. Various forms of dialysis, either alone or in combination, have been used to treat MALA, including intermittent HD [4–9, 11–15, 17, 19, 21], hemoperfusion (HP) [12], CVVHF [9, 11, 13, 20], continuous veno-venous hemodialysis (CVVHD) [15, 22, 23], continuous veno-venous hemodiafiltration (CVVHDF) [5, 15, 16], and plasma exchange (PLEX) [8], all with varying outcomes. In some cases, RRT is not utilized if the degree of acidosis or acute kidney injury is not severe or the patient is not acutely ill [10, 18, 25].…”