Interpreting the Consequences of Metformin Accumulation in an Emergency Context: Impact of the Time Frame on the Blood Metformin Levels

Table 1

Individual patient data and clinical settings, listed according to the time interval between sets of blood measurements. CKD: chronic kidney disease.

Case	Clinical features			Time interval after admission, hours	Biochemical features on and after admission
	Clinical setting	Dialysis (d) and/or vasoactive drugs (v)	Survival		Serum creatinine μmol/L	pH	Arterial lactate mmol/L	Lactic acidosis status	Plasma metformin mg/L, N < 1.35	Erythrocyte metformin mg/L, N < 1.65
All study parameters immediately available on admission
1	Acute aggravation of chronic heart failure	—	Yes	0	564	7.40	3.3	No lactic acidosis	9.7	4.8
2	No overt failure	—	Yes	0	—	7.40	5.4	No lactic acidosis	7.38	4.01
3	Sepsis	—	Yes	0	296	7.37	7.6	No lactic acidosis	7.6	2.53
4	Mesenteric ischemia, CKD	—	Yes	0	738	6.73	8.4	Lactic acidosis	66.8	20.1
Study parameters available partly on admission and completed some hours later
5	Multiple drug overdose	d	No	0	187	6.84	27	Lactic acidosis	ND	ND
				3	226	7.15	30	Persistence	56.7	18.6
6	Acute renal failure	—	Yes	0	776	7.20	20	Lactic acidosis	ND	ND
				4	745	7.23	18	Persistence	32.5	19
7	Acute aggravation of CKD	v	No	0	653	6.90	16	Lactic acidosis	ND	ND
				4	640	6.80	21	Persistence	43.3	8.7
8	Sepsis	v	No	0	161	6.70	28	Lactic acidosis	ND	ND
				5	160	6.67	26	Persistence	7.1	1.5
9	Multiple drug overdose	v	Yes	0	68	7.41	6.6	No lactic acidosis	ND	ND
				7.5	127	7.17	11.4	Appearance	64	19
10	Acute renal failure	d	Yes	0	1073	7.26	3.7	No lactic acidosis	ND	ND
				8.5	486	7.41	1.6	No lactic acidosis	15.8	19.4
11	Pulmonary embolism and CKD	—	Yes	0	292	7.36	5.2	No lactic acidosis	ND	ND
				9	305	7.31	4.6	No lactic acidosis	20.5	13.2
12	Acute renal failure	—	Yes	0	ND	7.31	10.5	Lactic acidosis	ND	ND
				11	538	7.14	14.4	Persistence	38	8.7
13	Sepsis	v	Yes	0	1327	7.02	10.8	Lactic acidosis	ND	ND
				11.5	1285	7.21	7.6	Persistence	50.1	18.5
14	Sepsis	—	Yes	0	231	7.45	6	No lactic acidosis	ND	ND
				17	244	7.39	1.7	No lactic acidosis	6.3	7.6
15	Acute renal failure	—	Yes	0	ND	7.20	5.7	Lactic acidosis	ND	ND
				39	928	ND	4.1	Disappearance	10.4	15.1
16	Sepsis	dv	Yes	0	958	6.91	16	Lactic acidosis	ND	ND
				40	353	7.42	1.7	Disappearance	39.9	16.8
17	Metformin overdose and acute renal failure	dv	Yes	0	1357	6.79	20	Lactic acidosis	ND	ND
				52	ND	7.36	2.1	Disappearance	11.4	11.3

Cases 5 and 9 concern the same patient.