A 72-year-old man has ST-segment depression of 2 mm in ECG lead II immediately after suprarenal aortic clamping. Which of the following is the most likely cause?
(A) Decreased left ventricular stroke volume
(B) Decreased venous return
(C) Increased left ventricular wall tension
(D) Reflex tachycardia
(E) Release of epinephrine from hypoperfused adrenal medulla
C
High positive end-expiratory pressure can result in each of the following EXCEPT
(A) decreased venous return
(B) increased functional residual capacity
(C) a left-to-right shift of the ventricular septum
Mepivacaine 40 ml of a 1% solution with epinephrine 1:200,000 is injected into the brachial plexus sheath at the axilla after eliciting a paresthesia in the ulnar nerve distribution. Which of the following is most likely to remain intact?
(A) Adduction of the thumb
(B) Flexion at the wrist
(C) Sensation of the lateral forearm
(D) Sensation on the palmar surface of the lateral three and one half fingers
(E) Sensation on the palmar surface of the medial one and one half fingers
Two hours after sustaining extensive burns of the head, neck and chest in a house fire, a patient has stridor and difficulty breathing. The most appropriate management is