Acquired methemoglobinemia in a third trimester puerpera and her premature infant with sodium nitrite poisoning: A case report

Table 2 Timeline of the disease course of the premature infant (December 14 to 19, 2021)

Parameter	Day 1	Day 2	Day 3	Day 5	Day 6
Disease course	Neonatal ICU				Clinical death
WBC as × 109/L	7.58	23.17	11.51	12.67
NEUT%	53.80	64.90	64.50	80.00
NEUT as × 109/L	4.08	15.06	7.42	10.14
LYMPH%	36.80	19.70	15.60	12.1
HGB in g/L	182.00	165.00	96.00	93.00
PLT as × 109/L	223.00	294.00	168.00	108.00
PT in s	71.90	NP	22.90	NP
PT as %	10.00	NP	39.90	NP
INR	6.16	NP	1.79	NP
FIB in g/L	1.42	NP	0.69	NP
APTT in s	41.30	NP	41.00	NP
TT in s	14.80	NP	19.20	NP
D-dimer in μg/mL	1.69	NP	5.13	NP
TP in g/L	44.55	NP	42.20	NP
ALB in g/L	26.83	NP	31.10	NP
AST in U/L	49.18	NP	165.30	NP
ALT in U/L	20.64	NP	55.10	NP
BUN in mmol/L	2.84	NP	12.20	NP
Cr in μmol/L	46.05	NP	64.5	NP
CK in U/L	150.12	NP	1313.75	NP
GLU in mmol/L	2.87	4.64	7.76	6.35	4.48
Ca2+ in mmol/L	2.14	NP	1.75	NP
Oxygen therapy	IMV	IMV	IMV	IMV
FiO2	80%	60%	60%	45%	40%
PEEP in cmH2O	6	5	5	4	4
PO2 in mmHg	136	83.8	267	81	119
OI in mmHg	170	140	445	180	297.5
PCO2 in mmHg	13.8	30.8	29.5	42	38
MetHb	3.3%	2%	NP	2%
pH	7.351	7.312	7.212	7.26	7.35
Lactates	NP	1.5	8.5	NP
Bicarbonate	7.5	15.5	11.8	23.8	21.6

ALB: Albumin; ALT: Alanine transaminase; APTT: Activated partial thromboplastin time; AST: Aspartate transaminase; BUN: Blood urea nitrogen; CK: Creatine kinase; Cr: Creatinine; CRP: C-reactive protein; FIB: Fibrinogen; GLU: Glucose; HGB: Hemoglobin; ICU: Intensive care unit; IMV: Invasive mechanical ventilation; INR: International normalized ratio; LYMPH: Lymphocyte; MetHb: Methemoglobin; NEUT: Neutrophil; NP: Not performed; OI: Oxygenation index; PCO₂: Carbon dioxide partial pressure; PCT: Procalcitonin; PEEP: Positive end-expiratory pressure; PLT: Platelet; PO₂: Oxygen partial pressure; PT: Prothrombin time; TP: Total protein; TT: Thrombin time; WBC: White blood cell.