David Dorsey | PubMed Health

PubMed2005

High-frequency oscillatory ventilation: lessons learned from mechanical test lung models.

OBJECTIVE: Review data obtained from high-frequency oscillatory ventilation (HFOV) and mechanical test lung models with respect to delivered tidal volume, distal pressure transmission, endotracheal tube cuff leaks, and simulated clinical conditions. DESIGN: Review of selected studies from PubMed, published abstracts, and institutional mechanical test lung data. RESULTS: Tidal volume delivery during HFOV is altered by oscillatory pressure amplitude (DeltaP), frequency (Hz), percent inspiratory time (IT%), and patient variables. Distal (carinal) oscillatory pressure amplitude transmission is directly correlated with endotracheal tube diameter and peripheral airway resistance. Endotracheal tube cuff leaks promote egress of tracheal gas while attenuating distal oscillatory pressure amplitude and tidal volume transmission. Simulated clinical conditions (e.g., increased distal airway resistance, mainstem intubation) may increase observed DeltaP, whereas mean airway pressure is decreased with air leaks. CONCLUSION: Mechanical test lung and artificial trachea simulations may provide useful information on the interaction of HFOV with altered lung mechanics and may contribute to the formulation of HFOV clinical strategies. Important limitations of these models include absence of gas exchange, histologic and biologic markers, or hemodynamic data.

High-Frequency Ventilation↗

PubMed2004

Pulmonary hemorrhage syndrome associated with an autochthonous case of dengue hemorrhagic fever.

Dengue fever is a major public health problem worldwide. Dengue hemorrhagic fever, a much rarer form of the disease, occurs when a person previously infected with dengue is re-infected with a different viral serotype. In recent years the infection rates of dengue and both clinical syndromes have increased along the United States-Mexico border. We present the case of a 61-year-old Laotian female who presented with a 1-week history of fever, altered mental status, oral ulceration, and rash. The patient developed diffuse pulmonary hemorrhage and anemia requiring multiple transfusions. She eventually sustained multi-organ system failure and expired. Both the titer data and serologies were consistent with the diagnosis of dengue hemorrhagic fever. We hypothesize that this syndrome was the result of re-infection occurring within the United States. This case is also unusual in that it is the second reported in the literature of pulmonary hemorrhages associated with dengue hemorrhagic fever.

Fatal Outcome↗