This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a colleague Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Hansen, L. K. Articles by Larsson, A. Search for Related Content PubMed PubMed Citation Articles by Hansen, L. K. Articles by Larsson, A. Related Collections Critical Care Physiology Ventilation

---

CRITICAL CARE AND TRAUMA

Are Selective Lung Recruitment Maneuvers Hemodynamically Safe in Severe Hypovolemia? An Experimental Study in Hypovolemic Pigs with Lobar Collapse

Lars Kjærsgaard Hansen, MD^*, Jacob Koefoed-Nielsen, MD^*, Jonas Nielsen, MD, PhD, and Anders Larsson, MD, PhD^*

From the *Department of Anesthesia and Intensive Care, Center for Cardiovascular Research, Aalborg Hospital, Århus University Hospitals, Aalborg; Clinical Institute, Århus University, Århus; and Department of Anaesthesia and Intensive Care, Copenhagen University Hospital Gentofte, Hellerup, Denmark.

Address correspondence to Lars Kjærsgaard Hansen, MD, Department of Anesthesia and Intensive Care Medicine, Aalborg Hospital, Århus University Hospitals, Hobrovej 18-22, DK 9000, Aalborg, Denmark. Address e-mail to lars.hansen{at}rn.dk.

BACKGROUND: We have previously shown, in normovolemic pigs, that a selective lung recruitment maneuver (S-LRM), i.e., insufflation of air-oxygen via a balloon catheter with its tip located in the bronchus of a collapsed lung lobe, effectively improves oxygenation and lung volume without affecting hemodynamics negatively. In this study, we examined the respiratory and circulatory effects of S-LRM during hypovolemia with compromised circulation.

METHODS: In eight ventilated (fraction of inspired oxygen, Fio₂ 1.0) and anesthetized pigs a balloon catheter was inserted in the bronchus of the right lower lung lobe. The lobe was selectively lavaged to create a dense lobar collapse. The pigs were then subjected to S-LRM (40 cm H₂O airway pressure for 30 s) at normovolemia, after venesection of 20% and 40% of the blood volume, respectively. Blood gases, compliance of the respiratory system (Crs), vascular pressures, and cardiac output were registered before, during, and after the S-LRM.

RESULTS: Pao₂, venous admixture, and Crs improved significantly with S-LRM at all three volume levels. No change in hemodynamics with S-LRM occurred in normovolemia and 20% hypovolemia. For 40% hypovolemia, cardiac output was unchanged by S-LRM, whereas minor decreases in mean arterial blood pressure were seen: 48 (37–52) mm Hg (median, 25th and 75th percentiles) 3 min before S-LRM, 40 (35–44) mm Hg at the end of S-LRM (P = 0.0207), and 47 (39–54) mm Hg 3 min after S-LRM.

CONCLUSION: A S-LRM effectively improved oxygenation and Crs and had only minor circulatory side effects, even in severe hypovolemia in this animal model of lobar collapse.