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+--- Thread: tca toxicity - ketty (/showthread.php?tid=181498)
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tca toxicity - ketty - ArchivalUser - 04-26-2007
. A 19-year-old woman with a long psychiatric history is admitted to the hospital after taking an overdose of amitriptyline. In the emergency room, she underwent gastric lavage and received activated charcoal. Serum toxicology screen revealed an amitriptyline level of 900 ng/ml. On the floor, she is awake but lethargic. Her blood pressure is 110/70 mm Hg and pulse is 63/minute. An electrocardiogram shows normal sinus rhythm. She is placed on an infusion of sodium bicarbonate. Over the next three hours, she becomes more somnolent and her respiratory rate decreases to 7/min. Her pulse is weak and rapid and her blood pressure is 75/40 mm Hg. The electrocardiogram now shows a narrow complex tachycardia at 160 beats per minute. Pulse oximetry reads 95% oxygen saturation on 6 liters/min of supplemental oxygen by nasal cannula. Arterial blood gas shows:
pH 7.32
pCO2 58
pO2 83
The first priority in caring for this patient is to
A. Administer quinidine, intravenously
B. Begin an esmolol drip, intravenously
C. Cardiovert the patient at 200 J
D. Intubate and hyperventilate the patient
E. Place a non-rebreathing mask with 100% supplemental oxygen
0 - ArchivalUser - 04-26-2007
D)
0 - ArchivalUser - 04-26-2007
i strongly believe in c}
0 - ArchivalUser - 04-26-2007
D? ABC. A first, B second. C third, because if repiration is not restored, cardioversion will be useless, the heart either cannot response, or return to arrhythmia after cardioversion.
0 - ArchivalUser - 04-26-2007
I think the correct answer is C, The pte. has a supraventricular tachycardia and he is unstable, the next step is cardiovert, you don't have to waste time to Intubate the pte, the most important step to increased survival is cardiovert, please Ketty put the answer.
0 - ArchivalUser - 04-27-2007
i think D correcting her ABGs will improve her condition
0 - ArchivalUser - 04-27-2007
intubation is ok, but hyperventilation will decrease her ICP, bp is already low, not good. I think c. Esomolol will decrease hr but will not convert.
0 - ArchivalUser - 04-27-2007
D. Intubate and hyperventilate the patient
0 - ArchivalUser - 04-28-2007
guys what a "non-rebreathing mask"???
0 - ArchivalUser - 04-28-2007
The most common arrhythmia related to TCA is Torsades de pointes (wide QRS and polymorphic). This patient has a narrow QRS tachycardia, with very low O2, very high CO2 and very low BP - all very strong justifications for sinus tachycardia. If a patient has a respiratory rate of 7/min and that ABG, it requires immediate intubation and ventilation.
A) Never, ever give quinidine with TCA or you will have a super huge long QT and TOrsades de pointes
B)No esmolol for severe low BP
C) It is most likely sinus tachy. The only tachy that should never be cardioverted
E) Non-Rebreathing: those masks shown in airplanes (safety instructions,in case of cabin despressurization). Not useful if the patient is not breathing (7/min)