Denise F Blake1, Philip Naidoo2, Lawrence H Brown3, Derelle Young4, John Lippmann5. 1. College of Marine and Environmental Sciences, James Cook University, Townsville, Emergency Department, The Townsville Hospital Townsville, Queensland, Australia 4814, E-mail: denise.blake@health.qld.gov.au. 2. Emergency Department, The Townsville Hospital, Townsville, Queensland, Australia. 3. Mount Isa Centre for Rural and Remote Health, James Cook University, Townsville. 4. Hyperbaric Medicine Unit, The Townsville Hospital, Townsville. 5. Divers Alert Network Asia-Pacific, Melbourne, Victoria, Australia.
Abstract
INTRODUCTION:High-concentration normobaric oxygen (O₂) administration is the first-aid priority in treating divers with suspected decompression illness. The best O₂ delivery device and flow rate are yet to be determined. AIM: To determine whether administering O₂ with a non-rebreather mask (NRB) at a flow rate of 10 or 15 L·min⁻¹ or with a demand valve with oronasal mask significantly affects the tissue partial pressure of O₂ (PtcO₂) in healthy volunteer scuba divers. METHODS: Fifteen certified scuba divers had PtcO₂ measured at six positions on the arm and leg. Measurements were taken with subjects lying supine whilst breathing O₂ from a NRB at 10 or 15·L·min⁻¹, a demand valve with an adult Tru-Fit oronasal mask and, as a reference standard, an oxygen 'head hood'. End-tidal carbon dioxide was also measured. RESULTS: While none of the emergency delivery devices performed as well as the head hood, limb tissue oxygenation was greatest when O₂ was delivered via the NRB at 15 L·min⁻¹. There were no clinically significant differences in end-tidal carbon dioxide regardless of the delivery device or flow rate. CONCLUSION: Based on transcutaneous oximetry values, of the commonly available emergency O₂ delivery devices, the NRB at 15 L·min ⁻¹ is the device and flow rate that deliver the most O₂ to body tissues and, therefore, should be considered as a first-line pre-hospital treatment in divers with suspected decompression illness.
RCT Entities:
INTRODUCTION: High-concentration normobaric oxygen (O₂) administration is the first-aid priority in treating divers with suspected decompression illness. The best O₂ delivery device and flow rate are yet to be determined. AIM: To determine whether administering O₂ with a non-rebreather mask (NRB) at a flow rate of 10 or 15 L·min ⁻¹ or with a demand valve with oronasal mask significantly affects the tissue partial pressure of O₂ (PtcO₂) in healthy volunteer scuba divers. METHODS: Fifteen certified scuba divers had PtcO₂ measured at six positions on the arm and leg. Measurements were taken with subjects lying supine whilst breathing O₂ from a NRB at 10 or 15·L·min⁻¹, a demand valve with an adult Tru-Fit oronasal mask and, as a reference standard, an oxygen 'head hood'. End-tidal carbon dioxide was also measured. RESULTS: While none of the emergency delivery devices performed as well as the head hood, limb tissue oxygenation was greatest when O₂ was delivered via the NRB at 15 L·min⁻¹. There were no clinically significant differences in end-tidal carbon dioxide regardless of the delivery device or flow rate. CONCLUSION: Based on transcutaneous oximetry values, of the commonly available emergency O₂ delivery devices, the NRB at 15 L·min ⁻¹ is the device and flow rate that deliver the most O₂ to body tissues and, therefore, should be considered as a first-line pre-hospital treatment in divers with suspected decompression illness.
Entities:
Keywords:
DAN (Divers Alert Network); Scuba diving; decompression illness; equipment; first aid; medical kits; oxygen; transcutaneous oximetry
Authors: Denise F Blake; Melissa Crowe; Daniel Lindsay; Annie Brouff; Simon J Mitchell; Neal W Pollock Journal: Diving Hyperb Med Date: 2018-12-24 Impact factor: 0.887
Authors: Denise F Blake; Melissa Crowe; Daniel Lindsay; Annie Brouff; Simon J Mitchell; Peter A Leggat; Neal W Pollock Journal: Diving Hyperb Med Date: 2020-03-31 Impact factor: 0.887