A 30-year-old woman develops urticaria immediately after administration of 2% 2-chloroprocaine for removal of a nevus on the chest wall. This reaction resolves with administration of diphenhydramine and the surgery is rescheduled. During the second procedure, a field block is performed using 10 ml of 1% lidocaine from a multidose vial. Within 10 minutes the patient develops urticaria and wheezing and has difficulty breathing. These symptoms resolve with administration of epinephrine. Which of the following substances is the most likely cause of these reactions?
(A) A paraben derivative
(B) Povidone-iodine
(C) Ethylenediaminetetraacetic acid (EDTA)
(D) Propylene glycol
(E) Sodium bisulfite
A
Which of the following factors causes a decrease in mixed venous oxygen saturation?
A 38-year-old woman with B-positive blood requires immediate blood transfusion during abdominal hysterectomy. No B-positive blood is available; O-negative blood is used. Three minutes after starting transfusion of packed red blood cells, the patient develops tachycardia, bronchospasm, and hypotension. Which of the following is the most likely cause?
(A) Anaphylactic reaction to donor IgA
(B) Bacterial contamination of transfused blood
(C) Hemolysis resulting from ABO incompatibility
(D) Hypocalcemia
(E) IgG-mediated reaction to Rh antigens
A
The condition LEAST likely to be associated with sustained pain relief following a nerve block is
Nine months after sustaining an injury to the left forearm, a 30-year-old woman has diffuse, burning pain on the anterior aspect of the forearm and posterior aspect of the hand and discoloration of the skin in the affected areas. The patient should be informed that
(A) if left untreated, muscle atrophy may develop in the involved limb
(B) if left untreated, the pain will remain well localized
(C) physical therapy is not indicated
(D) the symptoms are directly related to the severity of the initial injury
(E) the symptoms are most likely secondary to underlying peripheral vascular disease