Anesthesiology’s journal-based CME program is open to all readers. Members of the American Society of Anesthesiologists participate at a preferred rate, but you need not be an ASA member or a journal subscriber to take part in this CME activity. Please complete the following steps:

  1. Read the article by Duggan and Kavanagh entitled “Pulmonary atelectasis: A pathogenic perioperative entity” on page 838 of this issue.

  2. Review the questions and other required information for CME program completion (published in both the print and online journal).

  3. When ready, go to the CME Web site: Submit your answers, form of payment, and other required information by December 31 of the year following the year of publication.

The American Society of Anesthesiologists is approved by the Accreditation Council for Continuing Medical Education (ACCME) to sponsor continuing medical education for physicians.

The American Society of Anesthesiologists designates this continuing medical education program for a maximum of 1 hour of Category 1 credit toward the AMA’s Physician Recognition Award. Each physician should claim only those hours of credit actually spent in the activity.

Purpose:  The focus of the journal-based CME program, and the articles chosen for the program, is to educate readers on current developments in the science and clinical practice of the specialty of Anesthesiology.

Target Audience:  Physicians and other medical professionals whose medical specialty is the practice of anesthesia.

Learning Objectives:  After reading this article, participants should understand the pathophysiology of atelectasis, its clinical relevance, and approaches to potentially lessen its impact.

Authors – Michelle Duggan, M.B., and Brian P. Kavanagh, M.B.

Grants or research support:  Supported by the Canadian Institutes of Health Research, Ottawa, Ontario, Canada, and a Premier’s Research Excellence Award from the Ontario Ministry of Science and Technology, Toronto, Ontario, Canada.

Consultantships or honoraria:  None

Question Writer – Peter L. Bailey, M.D. Dr. Bailey has no grants, research support, or consultant positions, nor does he receive any honoraria from outside sources, which may create conflicts of interest concerning this CME program.

Based on the article by Duggan and Kavanagh entitled “Pulmonary atelectasis: A pathogenic perioperative entity” the April issue of Anesthesiology, choose the one correct answer for each question:

  1. Which statement concerning mechanisms known to contribute to compression atelectasis during anesthesia is most  likely true?

    • Caudal displacement of the diaphragm ensues rapidly after the induction of anesthesia.

    • Cephalad displacement of the diaphragm during anesthesia is worsened by the administration of neuromuscular blockers.

    • A shift of central blood volume from the abdominal to the thoracic compartment increases atelectasis.

    • Diaphragmatic respiratory excursion is greatest in its lower, dependent portion in the spontaneously breathing supine patient.

  2. Which statement concerning factors that can influence the formation of atelectasis is most  likely true?

    • All anesthetic agents produce atelectasis.

    • The distribution of mechanically delivered ventilation is more uniform in prone patients.

    • The inspired gas oxygen concentration does not influence the formation of atelectasis.

    • Awake individuals do not experience a decrease in functional residual capacity when changing from the upright to the supine position.

  3. Which statement concerning pulmonary pathophysiology is not  true?

    • Atelectasis-induced compression of extra alveolar vessels can increase pulmonary vascular resistance.

    • Atelectasis-induced hypoxic pulmonary vasoconstriction can increase pulmonary vascular resistance.

    • Cyclic mechanical ventilation with small tidal volumes prevents lung injury.

    • Mechanical ventilation with large tidal volumes can cause lung injury.

  4. Which statement concerning respiratory function and the impact of atelectasis beyond the operating room is most  likely true?

    • Postoperative pulmonary complications, even after elective abdominal surgery, are as great as 10%.

    • Atelectasis resolves within 1–2 hours in healthy surgical patients after laparoscopy.

    • The characteristic postoperative respiratory abnormality after abdominal surgery typically has an obstructive pattern.

    • Epidural analgesia, compared to systemically administered analgesics, consistently reduces the incidence of postoperative respiratory complications.

  5. All of the following are signs of lower lobe atelectasis on a conventional chest radiograph except 

    • the presence of an elevated hemidiaphragm.

    • displacement of the interlobar fissure.

    • absence of the “silhouette” sign.

    • compensatory overinflation of remaining lobar aerated segments.

  6. Which statement concerning the reversal of postoperative atelectasis with recruitment maneuvers (e.g., an inspiratory hold at 40 cm H2O for 20 seconds) and/or positive end-expiratory pressure (PEEP) is most  likely true?

    • The application of PEEP alone is sufficient to produce a sustained reversal of atelectasis.

    • The application of recruitment maneuvers alone is sufficient to produce a sustained reversal of atelectasis.

    • The application of recruitment maneuvers combined with PEEP does not produce a sustained reversal of atelectasis.

    • The application of recruitment maneuvers combined with PEEP can produce a sustained reversal of atelectasis.