All discussion involve egressing diver and divers scuba equipment.

Scenario 1:

(Discussions involving signs and symptoms of DCS)

Diver feeling over exerted, nausea, headache right after last recovery dive.

  • Pt. information
    • Vital Signs: BP: 110/70 P: 80, R: 24
    • Information: Patient was on second dive of day
    • First dive 30 minutes at 80 feet fresh water
    • Diver had a 15 minute surface interval before second dive
    • Second dive dive ended 30 minutes ago
    • Both dives were to 80 feet for recovery
    • Patient made a rapid ascent after 30 minutes at depth
    • Patient complained of numbness and tingling in arms and legs
    • Patient lost consciousness about 10 minutes before EMT’s arrival

Points to consider

  • Why rapid ascent?
  • Look at gauges / equipment
  • Was surface interval long enough?
  • Lung sounds / Pulse?
  • What about contaminated air?

Technical talking notes:

  • Surface interval too short
  • With a 15 minute surface interval, dive tables state maximum of 19 minutes an 80 feet for second dive
  • Air consumption should be considered. With diver SAC rate at 20.8 and a depth of 3.4 ATA (~80 feet) his supply would be 35 minutes.
    • 20.8 x 3.4 = 70.72
    • 2500 / 70.72 = 35.35 minutes
    • Diver has not only exceeded no decompression limits, he would have to exceed a safe ascend rate before running out of air


Scenario 2:

(Discussion revolved around mixed gases and partial pressures)

Convulsing Diver noted at the bottom, requiring full egress

  • Information:
    • Recovery depth was planned on ledge at 80 ffw
    • Pt gas used was EANX36 in 1 AL80 tank
    • Patient was noted by safety diver to be convulsing after 24 minutes of searching
    • Safety diver inserts regulator into mouth and ascends to surface from 130 feet
    • Patient is brought to surface and is unconscious

Points to consider

  • Safety diver now a potential Pt. Ascent obligations may have been breached.
  • Look at gauges / equipment
  • What is the depth of his gas rated for?
  • What could cause diver to convulse at depth?
  • What gas do you supply the convulsing victim?
  • How much decompression can you safely skip?
  • How do you manage your other team mates in assisting with rescue?
  • How do you communicate with and manage surface support during ascent?
  • If you choose to skip all your decompression stops on your rescue ascent, would you re-descend and if so how would you calculate your remedial decompression schedule?
  • Given the surface resources you have at hand, how would you treat the victim and organize evacuation and provide medium term emergency care?

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