A 68-year-old man with a past medical history ofhypertension, hemorrhagic stroke, and tobacco use and a familyhistory of coronary artery disease was convalescing in their familyhome after a recent hospital admission for community-acquiredpneumonia when he was noted to develop acute dyspnea. On arrival athis residence, the paramedics found the patient moaning, with aGlasgow Coma Scale score of 8 and increased work of breathing.
Upon arrival at the emergency department, histemperature was 36.8°C; heart rate, 47 beats/minute; bloodpressure, 97/56 mm Hg; respiratory rate, 36 cycles/minute; and hehad an oxygen saturation of 70% while he breathed oxygen via anonrebreather mask. The patient was intubated on an emergencybasis. The patient became progressively bradycardic andhypotensive. He was administered atropine in divided doses, 4 L ofcrystalloid solution, and was started on norepinephrine and sodiumbicarbonate infusions.
Physical examination after intubation and initiationof sedation revealed a well-nourished, unresponsive man. Thetrachea was midline and lungs were clear to auscultation. Cardiacexamination revealed regular bradycardia, no precordial heaves, anda grade III/VI holosystolic murmur along the left sternal border,which had not been noted during his previous hospitalization. Therewere diminished dorsalis pedis and radial pulses and his skin wascool to palpation. The abdomen was soft, nontender, and withoutorganomegaly. There was no asymmetric lower extremity edema
Chest radiograph performed in the emergency departmentrevealed a severely dilated right ventricle (RV) andinterventricular septal flattening. Computed tomography (CT)imaging of the head without injection of contrast dye, revealed noacute abnormality. Electrocardiogram reveals bradycardia and aninferior ST segment elevation.
ABG’s are as follows: pH – 6.9, PCO2 – 47 mm Hg, PO2 -49 mm Hg, HCO3 – 10 mEq/L. Peripheral blood cells: WBC – 16.9 3 103cells/ml, Hgb – 10.0 mg/dl. Blood studies: Na – 139 mEq/L, K – 6.2mEq/L, Lactate – 11.0 mmol/L, Anion gap 21, Troponin-I 10.82ng/ml.
Tasks:
1. Discuss briefly the pathophysiologic mechanism ofthe patient.
