Abstract

INTRODUCTION
Decompression sickness (DCS) results from a decrease in ambient pressure leading to supersaturation of tissues with inert gas and bubble formation. Perfluorocarbons (PFCs) are able to dissolve vast amounts of non-polar gases. Intravenous (IV) PFC emulsions reduce both morbidity and mortality associated with DCS, but the mechanism of this protective effect has not yet been demonstrated.
METHODS
Juvenile Dorper-cross sheep (n = 31) were anaesthetised and instrumented for physiological monitoring, IV fluid administration and blood sampling. Animals were compressed in air in a hyperbaric chamber to 608 kPa for 30 minutes and then rapidly decompressed. Upon decompression, animals were randomly assigned to receive 6 mmol per L of PFC or saline over 10 minutes beginning immediately after chamber exit. Arterial and mixed venous bloods were drawn at 5, 10, 15, 30, 60 and 90 minutes to examine pH, partial pressures of oxygen and carbon dioxide, oxygen saturation and electrolytes.
RESULTS
Compared to saline, PFC administration increased arterial oxygen content (16.33 ± 0.28 vs. 14.68 ± 0.26 ml per dL, P < 0.0001), mixed venous oxygen content (12.56 ± 0.28 vs. 11.62 ± 0.26 ml per dL, P = 0.0167), oxygen delivery (14.83 ± 0.28 vs. 13.39 ± 0.26 mmol per L kg, P = 0.0003) and tissue oxygen consumption (3.30 ± 0.15 vs. 2.78 ± 0.13 mmol per L kg, P = 0.0149) but did not increase extraction ratio (0.22 ± 0.012 vs. 0.21 ± 0.011, P = 0.5343).
CONCLUSIONS
It is likely that the improved oxygenation explains, at least in part, the previously-observed therapeutic effects of PFCs in DCS.

Authors

Smith CR, Parsons JT, Zhu J, Spiess BD

Institution

Department of Anesthesiology,Virginia Commonwealth University Reanimation Engineering Shock Center, Richmond, Virginia 23298-0695, USA. crsmith@vcu.edu

Source

Diving and hyperbaric medicine : the journal of the South Pacific Underwater Medicine Society 42:1 2012 Mar pg 10-7

MeSH

Analysis of Variance
Animals
Atmosphere Exposure Chambers
Carbon Dioxide
Cardiac Output
Decompression
Decompression Sickness
Electrolytes
Emulsions
Fluorocarbons
Infusions, Intravenous
Oxygen
Oxygen Consumption
Partial Pressure
Random Allocation
Sheep
Sodium Chloride
Time Factors

Pub Type(s)

Journal Article
Research Support, U.S. Gov't, Non-P.H.S.

Language

eng

PubMed ID

22437970