An incident occurred while teaching last weekend that I feel needs to be discussed.
Some background:
Instructors and DMs in landlocked areas will often teach classroom and pool sessions for a month and then journey to an Open Water site for certifications. It is not unusual to have an OW class, a Rescue Class, Avanced and/or Specialty classes running back to back or concurrently.
The students are limited to 3 training dives per day and are afforded adequate surface intervals. DMs and Instructors on the other hand, sometimes go from training session to training session with a fair amount of tank hauling and refilling, equipment setups, briefings, general running around serving student's needs, etc. All of this is done on generally shortened surface intervals.
Does this sound familiar to any dive professionals out there?
During the course of a training day an Instructor may conduct at least half a dozen training dives, some with CESAs and Alternate Air ascents. This makes for a lot of ascents and the necessity for reverse profiles.
Some known predisposing factors to the DCS incident are: Dehydration, vigorous exercise before and after dives, fatigue, stress, and in the case I will describe, altitude. There may be other unknown predisposing factors involved in the incident as well.
Here is a summation of the incident:
The Instructor involved is a 47 year old male, very fit, healthy, no known medical conditions, has close to 500 dives in various conditions from very cold water to warm tropics, and is a very conservative and disciplined diver.
He is actively diving throughout the year and as a full time instructor is teaching in the pool nearly everyday. He usually uses a conventional single tank/BC setup but also dives BP/W doubles w/longhose configuration and has generally dived dry for all but tropical vacations.
Last weekend, on the 8th training dive of the day he felt what he thought was a back spasm in upper back and shoulders while still about 5 feet underwater. This was on a slow ascent which followed an extended safety stop on a night dive where the group hovered prone on their backs enjoying the view of the stars for over 5 minutes at 15 feet.
Apon exiting the water and removing gear, the pain spread down his arms and within another couple of minutes the right arm was paralyzed. He sat down and twitching started in his right leg followed by paralysis. By this time he was rushed to a nearby hospital and placed on 100% O2. DAN was alerted. The total time from exiting the water to paralysis to being on O2 at the hospital was about 5 minutes.
After a couple of hours on O2 and an IV of a Magnesium solution and another with a Valium solution, the condition was resolved and all feeling and motor function returned to the extremities. He was given an EKG which looked excellent. Blood pressure normal. Heart rate normal. Blood test showed small electrolyte imbalance with slightly low potassium levels at 3.4L Normal is 3.5 -5.1. CK markers were above normal at 309 Normal range 35-232.
He stayed in ER overnight for a total of 8 hrs on O2.
Since the location was remote he waited until he was home the next day to do a Navy Table 5 hyperbaric O2 recompression. He shows no symptoms and apparently had a complete recovery.
The printouts from the dives downloaded off his computer show no actual ascent violations except on one CESA, all dives were ended with over 1000psi remaining. All evidence showed 8 relaxed comfortable dives. Earlier in the day (dive3) involved 2 CESAs and an Alt Air Ascent, with one CESA violating 30fpm.
Dive 6 was a Rescue dive where he played victim and the Rescuer ascended quickly but the computer did not show a violation.
Deepest dive was 70 feet. Longest dive was only 38 minutes. Most of the dives were betwen 25 and 50 feet and around 30 minutes. DTR on computer was never in caution zone. There was a reverse profile with first dive of the day to 70 feet followed by all the shallower dives and then final dive of the day was 70 feet.
DAN says 8 dives are too many in one day, esp. at 4600 feet. They say there were too many ascents. One DAN Dr. questions if it was actually a DCI incident.
The Instructor/victim is up and around, healthy and even taught a classroom session today.
Any diving medicine experts out there with an opinion? Anyone ever experience or hear of anything like this?
Has anyone heard of initial DCI symptoms occurring near the surface but still underwater?
It certainly has prompted changes in our dive center policy concerning certification weekends.
Some background:
Instructors and DMs in landlocked areas will often teach classroom and pool sessions for a month and then journey to an Open Water site for certifications. It is not unusual to have an OW class, a Rescue Class, Avanced and/or Specialty classes running back to back or concurrently.
The students are limited to 3 training dives per day and are afforded adequate surface intervals. DMs and Instructors on the other hand, sometimes go from training session to training session with a fair amount of tank hauling and refilling, equipment setups, briefings, general running around serving student's needs, etc. All of this is done on generally shortened surface intervals.
Does this sound familiar to any dive professionals out there?
During the course of a training day an Instructor may conduct at least half a dozen training dives, some with CESAs and Alternate Air ascents. This makes for a lot of ascents and the necessity for reverse profiles.
Some known predisposing factors to the DCS incident are: Dehydration, vigorous exercise before and after dives, fatigue, stress, and in the case I will describe, altitude. There may be other unknown predisposing factors involved in the incident as well.
Here is a summation of the incident:
The Instructor involved is a 47 year old male, very fit, healthy, no known medical conditions, has close to 500 dives in various conditions from very cold water to warm tropics, and is a very conservative and disciplined diver.
He is actively diving throughout the year and as a full time instructor is teaching in the pool nearly everyday. He usually uses a conventional single tank/BC setup but also dives BP/W doubles w/longhose configuration and has generally dived dry for all but tropical vacations.
Last weekend, on the 8th training dive of the day he felt what he thought was a back spasm in upper back and shoulders while still about 5 feet underwater. This was on a slow ascent which followed an extended safety stop on a night dive where the group hovered prone on their backs enjoying the view of the stars for over 5 minutes at 15 feet.
Apon exiting the water and removing gear, the pain spread down his arms and within another couple of minutes the right arm was paralyzed. He sat down and twitching started in his right leg followed by paralysis. By this time he was rushed to a nearby hospital and placed on 100% O2. DAN was alerted. The total time from exiting the water to paralysis to being on O2 at the hospital was about 5 minutes.
After a couple of hours on O2 and an IV of a Magnesium solution and another with a Valium solution, the condition was resolved and all feeling and motor function returned to the extremities. He was given an EKG which looked excellent. Blood pressure normal. Heart rate normal. Blood test showed small electrolyte imbalance with slightly low potassium levels at 3.4L Normal is 3.5 -5.1. CK markers were above normal at 309 Normal range 35-232.
He stayed in ER overnight for a total of 8 hrs on O2.
Since the location was remote he waited until he was home the next day to do a Navy Table 5 hyperbaric O2 recompression. He shows no symptoms and apparently had a complete recovery.
The printouts from the dives downloaded off his computer show no actual ascent violations except on one CESA, all dives were ended with over 1000psi remaining. All evidence showed 8 relaxed comfortable dives. Earlier in the day (dive3) involved 2 CESAs and an Alt Air Ascent, with one CESA violating 30fpm.
Dive 6 was a Rescue dive where he played victim and the Rescuer ascended quickly but the computer did not show a violation.
Deepest dive was 70 feet. Longest dive was only 38 minutes. Most of the dives were betwen 25 and 50 feet and around 30 minutes. DTR on computer was never in caution zone. There was a reverse profile with first dive of the day to 70 feet followed by all the shallower dives and then final dive of the day was 70 feet.
DAN says 8 dives are too many in one day, esp. at 4600 feet. They say there were too many ascents. One DAN Dr. questions if it was actually a DCI incident.
The Instructor/victim is up and around, healthy and even taught a classroom session today.
Any diving medicine experts out there with an opinion? Anyone ever experience or hear of anything like this?
Has anyone heard of initial DCI symptoms occurring near the surface but still underwater?
It certainly has prompted changes in our dive center policy concerning certification weekends.
