Shock due to amlodipine overdose
A 28-years-old woman, with no significant past history, presented with giddiness, abdominal pain, vomiting, breathlessness, and reduced urine output 12 hours after consuming 50 tablets of amlodipine [of 5 mg strength]. She was rushed to a hospital near her home, found to have hypotension with hypoxemia; was intubated, given gastric lavage, inotropic support and 24 hours later, shifted to our hospital At presentation she was found to have blood pressure (BP): 60/40 mmHg, heart rate: 128/min, respiratory rate: 32/min with spO2 on room air: 85%, raised central venous pressure [22 cm of saline], anasarca and crepititions in both interscapular area. She was admitted to the intensive care unit (ICU). Investigations revealed: Total leukocyte count: 18500/uL; neutrophils: 86%, serum creatinine: 1.8 mg/dl (normal range: 0.6-1.3 mg/dl), blood urea nitrogen 42 mg/dl (normal range: 10-20 mg/dl), and features of type -1 respiratory failure (pO2-48 mmHg, pCO2-26 mmHg, pH - 7.52, HCO3-22 mmHg). Ionized serum calcium (4.8 mg/dl; normal range: 4.6-5.6 mg/dl, serum albumin (3.9 mg/dl; range 3.5-5.5 mg/dl), and serum amylase (32 IU/L; range 18-108 IU/L) level at presentation were normal. X-ray of chest revealed bilateral reticulonodular opacities, upper lobar zone venous prominence, bilateral pleural effusion, and no cardiomegaly []. Her electrocardiogram was normal. Echocardiography revealed normal-sized chambers, valves, right and left atrial pressures, and left ventricular ejection fraction. Cultures of blood, urine, and tracheal aspirate were sterile. Intravenous inotropes were continued (dopamine: 10-15 μg/kg/min; noradrenaline: 10-12 μg/kg/min), systolic BP increased to 90-110 mmHg when iv frusemide was added. Two boluses of calcium gluconate were given (10 ml of 10% solution) 15 minutes apart, thereafter, low-dose infusion (at the rate 1 mg/kg of calcium) was started; ionized serum calcium level was maintained between 4.8-5.3 mg/dl. Thoracentesis was performed, 300 ml of exudative effusion (total count: 2800/cmm, leukocytes: 2400/cmm; predominantly lymphocytes; lactate dehydrogenase – 698 U/L; protein – 3 g/dL) was drained from either side. She was ventilated initially invasively, later non-invasively; and empiric broad-spectrum antibiotics covering Gram-positive, Gram-negative organisms and Pseudomonas aeruginosa were started in view of prior hospitalization. Monitored parameters included clinical status, central venous pressure, urine output, fluid, and electrolytes including calcium levels and ECG every 4-6 hrs for first 48, thereafter every 12 hours. Her urine output improved after 24 hours. She was successfully weaned off ventilator after 48 hours; inotropes (noradrenaline after 18 hours, dopamine after 48 hours) and calcium infusion (after 48 hours) were gradually tapered off. She was shifted to a step-down ward from ICU after 72 hours and discharged after 5 days.