DIVING ACCIDENT MANAGEMENT WITH PARTICULAR REFERENCES TO REMOTE LOCATIONS

Size: px

Start display at page:

Download "DIVING ACCIDENT MANAGEMENT WITH PARTICULAR REFERENCES TO REMOTE LOCATIONS"

Irma Fox
5 years ago
Views:

1 DIVING ACCIDENT MANAGEMENT WITH PARTICULAR REFERENCES TO REMOTE LOCATIONS Richard Dunford and Carrie Skiles Virginia Mason Medical Center 925 Seneca Street Seattle, WASHINGTON, U.S.A. Standard first aid measures for treating diving accidents are easily employed if evacuation, chamber and medical facilities are readily available. However, remote locations where no established evacuation system is in place present difficult choices. In such situations careful review of evacuation facilities, medical care and chamber availability, fee for service and local customs and immigration practices is necessary. It behooves each individual diving in remote locations to be as selfsufficient as is practical, be familiar with each piece of first aid equipment that is carried and investigate the local conditions for evacuation and medical care before commencing diving activity. BAStc ASSUMPTION OF RISK Often in the diving community, there is an assumption that if divers simply stay within decompression table limits and dive in a conservative manner they will avoid the need for any recompression facilities. This attitude ignores the unforeseen accident because of 19

2 Coldwater Diving For Science equipment failure, unexpected conditions underwater or undetected significant medical conditions among the diving party. It also ignores the well documented evidence that decompression risk exists, even for profiles carried out to plan and well within the limits of the U.S. Navy or other more conservative decompression tables. At Virginia Mason Hospital, a review of 75 diving accidents showed that 50% of those treated for decompression sickness were diving within No Decompression limits of the U.S. Navy tables and 40% of that group were diving within the limits of the newer more conservative decompression tables developed by the Defence and Civil Institute of Environmental Medicine in Canada (Nishi) and the Spencer-Huggins tables (Undercurrent) developed for the Edge computer. APPROPRIATE FIRST AID FOR DIVING ACCIDENTS It is imperative that all individuals involved in diving be prepared for a possible diving accident involving either air embolism or decompression sickness. A critical area of preparation is the knowledge and understanding of basic cardiopulmonary resuscitation (CPR). CPR techniques may be necessary for some extreme cases of decompression sickness, air embolism and cases of near drowning as well. Training in the techniques of CPR is cheaply and easily obtained through the American Heart Association or the American Red Cross. Learning this basic skill may prove to be a valuable adjunct in the field because it may allow a rescuer to temporarily maintain a diving accident victim's vital functions until more sophisticated techniques can be applied. The primary medical therapy to manage a diving accident is evacuation from the diving site to a hyperbaric chamber. Time is of essence because decompression sickness is a progressive disease that often worsens with time and becomes more difficult to treat. (Elliott). The evacuations are often carried out by plane or helicopter through such evacuation agencies as the Coast Guard or military. This is especially true in the more severe cases and in situations where long distances are involvea. However, evacuations are often carried out by private plane or automobile. In planning for potential evacuations, consideration must be given to local conditions such as possible effects of weather, availability and type of aircraft, time required to complete the 20

DUNFORD and SKILES. Accident Management evacuation and whether a member of the diving party will be required to accompany the victim to the evacuation destination.

3 DUNFORD and SKILES. Accident Management evacuation and whether a member of the diving party will be required to accompany the victim to the evacuation destination. The pnmary evacuation route is usually considered the most expedient method. Therefore, it is always advisable to have a backup plan that IS more conservative but more reliable in unfavorable conditions. One hundred percent oxygen is the primary first aid measure that can be administered at the dive site and during evacuation. While the role of oxygen is not technically proven as a medical adjunct, strong circumstantial evidence supports its use. For example, the Divers Alert Network has reviewed 200 diving accident records and observed that; a) administration of oxygen was followed by reversal of paralysis and sensory loss; b) the longer the 02 was delivered to a diving accident victim, the better the outcome for the diver, for both decompression sickness and air embolism, c) comparison of equally severe cases of decompression sickness and air embolism showed that those who received 02 had better eventual outcomes. Recommendations from the Divers Alert Network are that at least one hour, preferably two hours of oxygen should be delivered as minimum treatment to any diving accident victim and that the oxygen should be delivered as 100% inspired 02. A primary contraindication to administration of 100% oxygen is severe chronic obstructive pulmonary disease. However, it is highly unlikely that any individual with severe chronic obstructive disease would ever be involved in any type of diving. Also if 100% oxygen is delivered for 24 hours or more, it may cause pulmonary oxygen toxicity. Fluids are also recommended for diving accident victims since the pathology of decompression sickness involves fluid balance.(hallenbeck). In emergency room and hospital settings, patients are often given intravenous fluid. In the field, however, administration of IV's is impractical for the untrained individual so administration of fluids by mouth is common if tt.e patient is awake and alert.. If the patient is not awake or sufficiently alert to swallow, fluids by mouth should not be given because the diving accident victim may inadvertently aspirate the liquid into his lungs. Isotonically balanced fluids, such as Gatorade, are perhaps the best fluids available. The next option would be non-caffeinated, nonalcoholic beverages in the order of fruit juices followed by water and 21

4 Coldwater Diving For Science then soft drinks. The traditionally recommended position for a diving accident victim is the so-called "Trendelenberg position". It consists of the patient lying on his back with feet and torso elevated approximately 30 degrees. In addition, the "Trendelenberg position" requires that the individual be tilted approximately 15 degrees, onto his left shoulder. The latter aspect of the "Trendelenberg position" is an attempt to place the carotid arteries in such an anatomical position that any gas emboli passing through the aorta will bypass the entry points to the carotid arteries. The beneficial effects of the "Trendelenberg position", specifically in regards to the 15 degrees tilt to the left have been called into question. That position should not be maintained if it compromises other aspects of treating and evacuating the accident victim. If that diving accident victim requires CPR, then CPR should be administered with the diving accident victim positioned flat on his back. A second position that is being sanctioned by the Divers Alert Network is called the Decubitus position. It is a similar position, except that the patient is rolled onto his left shoulder such that alliance of the shoulders is vertical. The advantage to the Decubitus position is that if a patient vomits it is unlikely the vomitus will be aspirated back into the lungs causing potentially lethal aspiration pneumonia. A final field adjunct in delivering first aid to diving accident victims is adequate communication to the local rescue agencies and the local medical authorities. Communications can be used to alert evacuation agencies, fine tune the pickup, alert the chamber to a pending arrival and receive medical instructions for the benefit of the patient. THE REMOTE LOCATION The single most beneficial action individuals can take to aid a diving accident victim in situations where long delay2 are expected, is to have available and administer 100% oxygen. The guiding principle in delivering oxygen is to administer 100% 02 for as long as possible (but not to exceed 24 hour continuous administration). There are many types of oxygen delivery systems on the market but in choosing one, factors such as portability, efficiency, length of oxygen delivery and ease of use (for operator) must be considered. 22

5 DUNFORD and SKILES. Accident Management The typical E cylinder used in medical emergency rescue devices contains approximately 725 liters. At a flow rate of approximately 6 liters per minute (typical ventilatory volume of an average individual), an E cylinder would last approximately 100 minutes. (Nearly meeting the recommended two hour minimum time of 02 delivery by the Divers Alert Network). However, depending on the type of interface with the patient and the ventilatory rate of the individual, the oxygen delivery time of these systems may vary. The disposable emergency room mask and nasal prong are not sufficient to deliver 100% 02 even if the supply rate is increased to liters per minute. The disposable, tight-fitting mask with the reservoir bag can deliver up to 80% if the flow rate is kept at approximately 10 liters per minute. While these systems are simple and lightweight, they do not deliver 100% 02 and they require excessive flow rates for maximum inspired 02. An adequate oxygen delivery system is the bag valve mask system, or, commonly called the AMBU bag (air mask bag unit), consisting of a tight sealed face mask and a one-way valving system with reservoir bag. The system allows for active inflation of the victim's lung by the rescue personnel or for the patient to inhale on their own. The primary purpose of the bag mask valve is to aid in ventilation of a non-breathing patient. It can be adapted to an 02 source and deliver 100% inspired 02. However, training is required in its use in order to maintain a good seal while administering adequate tidal volume, and most models are somewhat bulky. Oxygen Delivery systems that operate on the demand principle are most efficient for a conscious patient. Demand systems deliver oxygen to the patient when initiated by the negative inspiratory efforts of the patient. No intervening medical personnel are required to operate the equipment itself (but should be present to assist the patient if needed). The patient only receives oxygen as he inhales from the syst~m. These systems are easy to administer as long as a good face seal or mouth piece can be provided. They are commercially available as a package including oxygen cylinder, a demand regulator and associated face masks, and are normally packed quite securely for transit. Another variation of the demand system, are high pressure fittings that adapt scuba regulators to various types of oxygen 23

6 Coldwater Diving For Science bottles. While this is a simple and efficient system, it allows a nonoxygen cleaned scuba regulator to come into contact with pressurized 100% 02. The disadvantage of demand systems is that they are only effective for the spontaneously breathing patient and not effective to aid in the non-breathing patient. However, it has been noted by the Divers Alert Network that the vast majority of diving accidents involve a breathing, conscious patient. Therefore, this type of system would usually meet the needs of mos~ of the diving accident victims. Use of pneumatic pressure by non-trained individuals to inflate a patient's lungs is not recommended by Divers Alert Network. The force provided by the unit may be enough to injure the lung, compound arterial embolization or force aspiration of vomitus which would subsequently cause aspiration pneumonia. The purge button on a scuba regulator can be used as a pneumatic power inflator but is exceptionally dangerous because of the lack of control over the pressure delivered to the lung. A final type of 02 delivery system to be mentioned is an oxygen re-breathing system. At one time this type of system was available on the market, but does not currently appear to be. However, because the system is very efficient in delivering 100% 02 for long periods of time and because it is mechanically very simple and could be easily be constructed, it is being described here (see figure 1). The patient is connected to a one-way breathing valve that passes the expired gas through a C02 absorbent and has an oxygen source to replenish the system. A reservoir bag acts as a compliance system and as an indicator of system volume. A purge valve is utilized periodically to purge the system since nitrogen elimination from the patient will dilute the oxygen concentration. The tremendous advantage of this system is that since an individual will consume approximately 0.25 liters of oxygen per minute, a 725 liter oxygen tank would last well in excess of 24 hours. The disadvantage of this system is that it must be purged periodically to clean out the excess nitrogen accumulated from the patient and secondly, condensation from the expired air will collect in the tubing. This condensation coming in contact with C02 absorbent can develop an acidotic vapor that can injure the lungs. Therefore, the system must be purged frequently to keep the condensation to a minimum or a drying element must be introduced 24

7 DUNFORD and SKILES. Accident Management into the system. A further disadvantage is that these systems are not currently being marketed and must be homemade. Fi~ure 1. Oxygen Rebreathing System Oxygen - A final note about oxygen is that if inadequate supplies exist, a remote source of oxygen in the local community must be utilized. This may require adaptation to unusual or non-standard fittings. The amount of available oxygen cannot be guaranteed. The quality of the oxygen to be found available in remote locations is another issue. It may be of industrial quality, the levels and quantities of contamination, or type of contamination will be unknown. The choice between using and not using this type of oxygen source for diving accident victims, whose state may be deteriorating, is difficult and not without risk. But given the choice of the long delays for treatment in remote locations, it is probably advisable to take a chance and use the available oxygen. In deciding what type of system to be carried into the remote location, individuals must decide what type of situation they will attempt to manage. CPR may be effective for approximately one-half hour. A non-breathing diving accident victim with a functioning heart may be sustainable for many hours. A bag valve mask system 25

8 Coldwater Diving For Science is the system of choice to deliver 100% 02, in this situation, but use of these systems requires training. On the other hand, the majority of diving accident victims are a breathing patient where oxygen was of great value. As a minimum, a 100% inspired 02 demand system is required. Ideally, there should be a sufficient quantity of 02 available to last through the evacuation but as a practical minimum, enough 02 to exceed the 2 hour minimum. Two E cylinders should be carried. An area of critical importance to diving safety in remote locations is availability of 24 hour communication. Communications are necessary to alert the rescue agencies that are available and to execute evacuation plans. In addition, it is possible to obtain medical advice, be alerted to a change in rescue plans, develop innovative plans to circumvent obstacles, and obtain help from local authorities or United States representatives in expediting evacuation plans. Evacuation from a remote diving location is highly variable and difficult to describe and is usually a "make the best with what is available" situation. The destination of the evacuation however, deserves some consideration. There may be a local medical facility available but an assessment must be made as to the level of training of the local medical authorities which are at times excellent and at times highly inadequate. As a last resort, adequate communications may be utilized in order to aid the local medical authorities in proper care procedures if the need arises. The local hyperbaric chamber systems must also be carefully considered. The fact that a local chamber exists, does not necessarily make it an appropriate facility. Some remotely located chambers are non-standard and poorly maintained. These systems should be checked out either through the Divers Alert Network or an on-site visit. Evaluating the capability of the chamber staff may be a more essential item than inspecting the charrber system itself. Determining how many individuals have been treated in that system, who the mecilcal authority is, and the level of training received, are a few of the essential questions to be asked of these staff people. In this regard, it is the author's opinion that more individuals are injured in hyperbaric chambers due to faulty medical procedures than a failure of the hardware system. 26

9 DUNFORD and SKILES. Accident Management Long distance evacuations often require not only hours of time for the rescue team to reach the dive site or landing site, but also hours of time in returning to the hyperbaric chamber. These evacuations and subsequent medical care tend to be expensive and the service agency may demand payment before carrying out the evacuation or treatment. It is therefore important for individuals to have a source of available cash to cover such emergency situations. In addition, many personal insurance policies do not cover foreign evacuation costs or foreign medical care. Often individuals assume that in-water recompression IS an acceptable alternative to evacuation from a remote location. There are currently a number of articles in the literature on techniques of in-water recompression. (Farm, 1986; Edmonds, 1984) These techniques have been used in treating cases of decompression sickness in remote locations and have also been used as a first aid measure while transportation is being arranged. However, in planning this type of maneuver, it should be realized that in-water therapy could take up to 3 hours and cold, or other environmental factors must be managed, and the diver must be accompanied by an attendant. Training in recompression therapy is highly desirable because it is likely that the more critical the diving accident, the more likely an in-water recompression will be attempted. On the other hand, the critical diving accident will be more difficult to manage, especially if that individual's consciousness level or breathing is affected. Because the patient is breathing 100% 02 at 30 feet, this does not insure that a favorable response is forthcoming. Many cases of recompression therapy are complicated and difficult to medically manage under the best of conditions. The procedure must be carried out in a safe harbor with; a) full face mask with demand valve, surface supply system or helmet with free flow, b) an adequate supply of 100% oxygen for the patient and air for the attendant, c) thermal protr~ction which would be a minimum of a wet suit, d) 10 meters of rope with harness for the patient, e) communication system between the patient and/or the attendant to the surface, f) a copy of the planned profile to be carried out and g) communication link to medically trained diving specialists. Inadequate training or preparation can lead to serious complications in regard to the diving accident victim's well being. 27

10 Coldwater Diving For Science In conclusion, it is imperative that those individuals diving ill remote locations understand that not all medical emergencies can be successfully dealt with. An unsuccessful management of an emergency problem may result in permanent injury or fatality. It must be understood that the more remote the diving location and therefore, the further from adequate medical facilities, the more medical conditions will be rendered unmanageable. Divers in remote locations should consider what type of diving medical emergency they are capable of handling, obtain the proper equipment and training necessary to manage an accident, and not carry equipment that they are not trained to use. Essential first aid elements for all divers to carry are oxygen with delivery system, communications that can operate on a 24 hour basis and thorough understanding of the local medical facilities, chambers, local evacuation routes, potential customs complications and if possible, a backup evacuation route. BIBLIOGRAPHY Dick, Arthur, P. Bennett and J. Miller Alert Diver, The Newsletter of the Divers Alert Network, Volume II, number 1. Edmonds, Carl, C. Lowry and J. Pennefather Diving and Subaquatic Medicine, Diving Medical Center Publications, Third Edition. Elliott, D. H. and J. M. Hallenbeck "The Pathophysiology of Decompression Sickness". In The Physiology and Medicine of Diving and Compressed Air Work, edited by P. B. Bennett and D. H. Elliott, 2nd ed., London: Bailliere Tindall. Farm, Frank, E. Hayashi and E. Beckman ~ Grant Technical Paper, Diving and Decompression Sickness Treatment Practices Among Hawaii's Diver Fisherman. Hallenbeck, J. M. and J. C. Andersen Pathogenesis of the Decompression Disorders, The physiology and Medicine of ljiving, edited by P. B. Bennett and D. IT. Elliott, 3rd ed., London: Bailliere Tindall. Nishi, R. Y., B. C. Eatock, 1. P. Buckingham, and B. A. Ridgewell Assessment of Decompression Profiles, by Ultrasonic Monitoring, Phase III: No-Decompression Dives, Defence and 28

11 DUNFORD and SKILES. Accident Management Civil Institute of Environmental Medicine. Undercurrent. The Private Exclusive Guide For Serious Divers, Volume II, No.5, May,

COALINGA STATE HOSPITAL. Effective Date: August 31, 2006

COALINGA STATE HOSPITAL. Effective Date: August 31, 2006 COALINGA STATE HOSPITAL NURSING POLICY AND PROCEDURE MANUAL SECTION Emergency Procedures POLICY NUMBER: 702 Effective Date: August 31, 2006 SUBJECT: CARDIOPULMONARY RESUSCITATION (CPR) 1. PURPOSE: To provide