No booze,No Strenous activity after diving!
Following is a response to the article above after posting the discussion in forums!
What the experts say!
On drinking alcohol and scuba diving.
Mainly it is a bad idea but there is another school of thought!
You would have thought that this subject will have a general consensus among the experts in Dive medicines as a Bad Idea. But interestingly and contradictorily, there are detractors among the specialist, citing strong evidence to support their contentions.
Experts on diving medicine don't agree totally , and have different opinions on the effects of alcohol and diving.
DAN's (divers alert network)
Simply put, alcohol and diving are not compatible. Alcohol causes depression of the central nervous system, which impairs judgment and reduces reaction time and coordination. Often the individual is not even aware of the degree of impairment. A review of more than 15 studies on the effects of alcohol on performance found that alcohol was involved in roughly 50 percent of all accidents in people of drinking age. In Diving and Subaquatic Medicine (Edmonds C, et al., 2002), the authors report that alcohol is associated with up to 80 percent of all drownings in adult males. It takes time for alcohol to be metabolized and its effects to wear off. M.W. Perrine and colleagues studied a group of experienced divers and the impact of alcohol consumption on their performance.. The study went on to state that situational awareness and protective inhibitions may be reduced. Recent alcohol intake (along with seasickness, traveler's diarrhea, excessive sweating, diuretic medications and air travel) is a potential cause of dehydration in divers. Alcohol ingestion may also enhance the effects of nitrogen narcosis. Elevated BAC, dehydration and nitrogen narcosis together may result in otherwise preventable accidents due to decreased problem-solving ability. Many divers appreciate a cold beer, but drinking and diving can turn a safe activity into a unwanted bad experience for both the diver and all those impacted by a rescue or fatality. Think twice before combining alcohol and diving
Scuba docs has this to say :
Beer While Diving?
Some divers insist that drinking beer before, during and after their dives has no risk if consumption is not excessive. Is there any danger in drinking alcoholic beverages and diving? The short answer is that by drinking alcohol before and during diving trips increases the risks not only to themselves but their dive buddies!
Blood Alcohol Concentration (BAC) Research has shown that there is a definite reduction in the ability of the individual to process information, particularly in tasks that require undivided attention for many hours after the blood alcohol level has reached 0.0%. This means that the risk for injury of a hungover diver is increased significantly, particularly if high BAC levels were reached during the drinking episode. The AMA upper limit of the BAC for driving a vehicle in the US is 0.05%. Surely diving with any alcohol on board would be foolish, considering the alien environment (water) and the complex skills required to follow no deco procedures.
All of the following behavioral components required for safe diving are diminished when alcohol is on board or has been on board in the prior 24 hours: Reaction time Visual tracking performance Concentrated attention Ability to process information in divided attention tasks Perception (Judgment) The execution of psychomotor tasks. The individual who has alcohol onboard may not feel impaired or even appear impaired to the observer but definitely is impaired and this is persistent for extended periods of time. The use of alcohol, even in moderate doses, clearly carries a self-destructive aspect of behavior and leads to higher probabilities for serious accidents. Alcohol causes dehydration (a diuretic) In addition to these dangers is the definite danger of alcohol-produced dehydration. Dehydration is considered to be one of the prime causes of decompression illness. Alcohol in any form has a direct effect on the kidneys, causing an obligatory loss of body fluids. If your drinking buddy is an intelligent diver, surely he will understand that this is not preaching- a cool beer is appreciated by the author-but by drinking and diving he can turn a safe sport into a nightmare for himself and his family. I'm sure that when he considers that he is also endangering his buddy that he will think twice before drinking alcohol before and while diving. There have been recent discussions in scuba magazines, chat rooms and scuba forums that it's OK to drink beer between dives during a surface interval. Some divers insist that drinking beer before, during and after their dives is acceptable citing personal experiences and maintaning that nothing untoward has ever happened.
So, Is there any danger in drinking alcoholic beverages before , in between and immedaitely after diving? General consensus among the experts seem to indicate that it is a bad idea and the risks of DCS is increased by doing so! Dr. Glen Egstrom, PhD has stated the problem succinctly: He made personal review of over 150 studies on the effects of alcohol on performance has resulted in the following observations:
1. Ingestion of even small amounts of alcohol does not improve performance: to the contrary it degrades performance
2. While there are variables that can speed up or delay the onset of the effects of alcohol, they are minor issues which do not overcome the decrements to the central and peripheral nervous system.
3. Alcohol can be cleared from the blood at a predictable rate. Generally on the order of .015% BAC per hour. This does not necessarily mean that the decrements in performance have been completely eliminated in that time.
4. Alcohol is a depressant drug that slows certain body functions by depressing the entire central nervous system. Effects are noticeable after one drink.
5. The effects are mood elevation, mild euphoria, a sense of well being, slight dizziness and some impairment of judgment, self control, inhibitions and memory.
6. Increases in reaction time and decreases in coordination follow the dose/response curve quite well.
7. Alcohol is involved in 50% +/- of all accidents involving persons of drinking age.
8. The deleterious effects of alcohol on performance are consistently underestimated by persons who have been drinking alcohol.
9. Divided attention tasks are found to be affected by alcohol to a greater degree than those tasks with single focus of concentration, i.e. a task such as a head-first dive into shallow water, with many interrelated decisions necessary to a successful dive, will be impacted to a greater degree than lifting a heavy weight.
( click the titles to link to the full articles)
Detractors opinions below:
Diving research"Alcohol and DCI"
But interestingly, there are many experts in the field of dive medicine who actually disagrees with the general consensus that alcohol and diving is just bad news.
Quote from an article " in a study of 440 divers, incidence of DCS in those who frequently drank wine was lower than in those who did not. Recent research on mortality from heart disease has suggested that drinking red wine may protect against heart disease by way of vasodilation. It may be, then, that such vasodilation may improve the movement of nitrogen bubbles through the circulatory system, leading to faster elimination of small bubbles. " unquote. (brief extract from the article suggesting among the experts that not enough data to definitively suggest alcohol and diving is dangerous.)
1. there are no data showing an association between alcohol use and DCS risk;
2. everybody thinks there are; 3. there are theoretical reasons to suspect a link, but these remain unstudied and unproven.. Although conventional wisdom holds that alcohol use, either before or after diving, contributes to the development of DCS, there are no data supporting this contention.
Current policy Alcohol use is described as a risk factor for DCS in the dive training manuals of all the major diving certification agencies as well as numerous books and articles on diving and DCS. DAN cautions against drinking before or after diving, citing alcohol's effect on judgment and the dehydrating effects of alcohol, which may inhibit nitrogen off-gassing The training manual of the Professional Association of Dive Instructors (PADI) instructs divers to avoid alcohol before, between, and at least two hours after diving, stating emphatically that alcohol "causes dilation (enlarging) of the blood capillaries, increasing circulation. Drinking alcohol prior to a dive will cause increased nitrogen absorption during a dive. Drinking alcohol after a dive will release nitrogen much too quickly, possibly contributing to bubble formation" Books on deep diving similarly caution against drinking, often giving no particular reason (Gilliam & Von Maier, 1992; Lippmann, 1992). Yet,in a later article [Gilliam, 1994], criticized some of the conventional wisdom of diving, including the rule "you can't dive if you have a beer with lunch." Gilliam noted that alcohol has the same dehydrating effect as caffeinated beverages, and that the effect of moderate consumption of these beverages is of little consequence. He concluded that "a few sacred cows continue to moo long after their milk ran dry"
Link to the full article at Diving research"Alcohol and DCI"