An 18-month-old child with tetralogy of Fallot is anesthetized with halothane and nitrous oxide. Following intubation, oxygen saturation decreases abruptly from 85% to 45%. The most effective treatment is
A 72-year-old man has had residual hemiparesis since having a cerebrovascular accident three years ago. Compared with the response of the unaffected limbs to nondepolarizing muscle relaxants, the hemiparetic limbs will show
(A) the same response
(B) greater depression of tetanus
(C) greater twitch depression
(D) less twitch depression
(E) less post-tetanic facilitation
D
In the majority of cases, fetal heart rate decelerations in a variable pattern are associated with
(A) decreased uteroplacental perfusion
(B) fetal head compression during contractions
(C) umbilical cord compression
(D) low Apgar scores at birth
(E) low neurobehavioral scores eight hours post partum
A patient suddenly makes a respiratory effort during craniotomy for clipping of a cerebral aneurysm in a 15-degree head-up position with controlled ventilation. The most likely cause is
During use of the ventilator on an anesthesia machine, positive pressure is noted on the airway pressure gauge during exhalation. Positive end-expiratory pressure has not been purposefully added to the breathing circuit. Which of the following is the most likely cause?
(A) Closure of the pop-off valve in the circle system
(B) Excessive tidal volume settings on the ventilator
(C) Obstruction of the pressure relief valve on the scavenging system
(D) Overinflation of the endotracheal tube balloon