dosage of a medication should be at least equivalent to the IV route, and is
usually 2 to 2.5 times the IV dose is administered. The patient in the scenario
should receive epinephrine via the ET while IV access is established.
194.The answer is e.(Tintinalli, pp 184-185.)This ECG shows atrial fib-
rillation with rapid ventricular response (RVR).Normally, one area of
the atria depolarizes and causes uniform contraction of the atria. In atrial
fibrillation, multiple areas of the atria continuously depolarize and contract,
leading to multiple atrial impulses and an irregular ventricular response.
Atrial fibrillation reduces the effectiveness of atrial contractions and may
lead to or worsen heart failure in patients with left ventricular failure. Treat-
ment of atrial fibrillation is dependent on whether or not the patient is sta-
ble or not. This patient is clinically unstable;the atrial fibrillation with
RVR has pushed him into heart failure and he is hypotensive and tachyp-
neic. Unstable patients like this should undergo synchronized cardiover-
sion.Synchronized cardioversion is performed at 100 J and then at 200 J
if the first attempt fails.
The focus of emergency management in stable patients with atrial fib-
rillation with RVR is ventricular rate control. Diltiazem (b)or verapamil are
excellent choices for rate control. Metoprolol (c)or digoxin (d)may also be
used, but may depress BP. Recall that patients in atrial fibrillation for longer
than 48 hours are at risk for atrial thrombi. If these patients are cardioverted
(electrically or chemically) they have a 1% to 2% risk of arterial embolism.
Since it is often difficult to determine time of onset, ED patients are gener-
ally only cardioverted if they are unstable. Stable patients with atrial fibrilla-
tion should be anticoagulated with a loading dose of (a)heparin and oral
warfarin for at least 1 month prior to elective cardioversion.
195.The answer is a.(Tintinalli, pp 1722-1725.) This patient is in
hypovolemic shocksecondary to blood loss from a femoral fracture.
Hypovolemic shock occurs when there is inadequate volume in the circula-
tory system, resulting in poor oxygen delivery to the tissues. Hemorrhage,
GI losses, burns, and environmental exposures can all be responsible for
hypovolemic shock. In trauma, hemorrhage is the most common cause of
hypovolemic shock. This patient fractured his femur, disrupting the nearby
vascular supply, resulting in significant blood collection in the soft tissue.
This patient’s hypovolemic shock can be treated with aggressive fluid
and blood-product replacement. In the meantime, pain control and x-rays
of the hip, femur, and knee should be performed. Once the femur fracture
Shock and Resuscitation Answers 223