Medical care in technical settings is not just emergency medical services being provided on a mountain,^47,⁶³ nor is it the same as combat casualty care; however, there are similarities to both. Care is usually delayed as compared with most prehospital settings. There is more blunt and less penetrating trauma than in combat casualty care.²⁶ Victims with serious airway problems or severe bleeding are likely to be dead by the time that medical care arrives, although immediately life-threatening bleeding is less likely from blunt trauma than from penetrating trauma.

It is challenging to provide medical care in technical environments. In addition to the limitations of wilderness medicine (i.e., the art of the possible), there are dangers for both the rescuer and the patient. Medical providers who plan to work in technical terrain should have adequate skills to ensure that they can function safely under the conditions that they expect to encounter. These skills should be learned by proper instruction and training before traveling in technical terrain and providing medical care in wilderness and remote areas.

Definitions

Technical Terrain

Technical terrain is terrain in which travel is difficult or dangerous and that may require the use of special equipment (e.g., ropes) for safe travel. Examples include mountainous terrain with cliffs or very steep slopes (i.e., rock, snow, or ice) and glaciers. Operations in technical terrain include mountaineering and climbing, glacier travel, canyoneering (usually called canyoning outside of North America), and caving.

Self-Rescue

Self-rescue refers to the removal of ill, injured, or stranded members of a party from a dangerous or unstable situation by members of the same party. In extreme cases, an ill or injured person may have to rescue himself or herself. Examples include the lowering of an injured climber (i.e., “climber pick-off”) by a climbing partner and the extracting of a person from a crevasse on a glacier. This chapter is mainly concerned with self-rescue in technical terrain.

Evacuation

Evacuation is the removal of a person who may be ill or injured from an area in which medical care and other resources (e.g., food, water) are limited to an area in which resources are available or in which a higher level of medical care can be provided.

Epidemiology

Wilderness travel is generally quite safe, with the exception of various high-risk activities such as high-altitude mountaineering,³⁰ backcountry skiing in avalanche terrain, and paragliding. There are limited data about the types of illness, injury, and death of wilderness travelers and even less about the types of morbidity and mortality of rescuers. Rescuers should be especially well prepared for the most common causes of injury and illness in victims.

Risks of Wilderness Travel

“No American wilderness that I know of is so dangerous as a city home ‘with all the modern improvements.’ One should go to the wilderness for safety, if for nothing else.”

—JOHN MUIR ⁵¹

In a study of helicopter rescues and deaths among trekkers in Nepal from 1984 to mid 1987, there were 23 deaths and 111 helicopter rescues with a total of 148,000 trekking permits.⁶⁹ The incidence of helicopter rescue was 75 per 100,000, and the incidence of death was 15 per 100,000. The most common causes of death were trauma (11 persons), illness (8 persons), and altitude illness (3 persons). In a follow-up study of deaths among trekkers in Nepal from mid 1987 to 1991, there were 40 deaths among 275,950 trekkers, for a death rate of 14 per 100,000.⁶⁸ Trauma was the cause of 12 deaths, and altitude illness caused 10 deaths. There were 4 deaths thought to be caused by heart attacks and 3 deaths from apparent diabetic ketoacidosis above 4000 m (13,100 feet). A small cohort study in one trekking group in Nepal showed that the rates of illness were similar between trekkers and porters.¹

In the Alps, an Austrian study estimated the death rate for mountain hiking at 4 per 100,000 hikers annually. About 50% of these deaths were sudden cardiac deaths.¹⁰

In North America, there have been several studies in national parks. Some of these are difficult to interpret, because they include both wilderness and nonwilderness activities. In a study of national parks in the state of Washington, the overall injury rate was 22 per million visits. Two-thirds of the injuries occurred during hiking (55%) and mountaineering (12%), but the number of visits related to these activities was not reported.⁷¹ A California study that looked only at wilderness activities estimated a mortality rate of 0.26 deaths per 100,000 visits, mostly as a result of heart disease, drowning, and falls.⁴⁸ The rate of nonfatal events was 9.2 per 100,000 visits. Injuries accounted for more than 70% of all nonfatal events, and these most frequently affected the lower extremities (38%).

The risks of climbing in wilderness areas are harder to quantify. In data from mountaineering accidents in North America that included climbing accidents in nonwilderness areas from 1951 to 1995, 80% of the accidents involved a fall or a slip or being hit by a falling object.³⁶ In more recent figures (covering 1951 to 2007 in the United States and 1951 to 2005 in Canada), 71% involved a fall or a slip or being hit by a falling object, 4% involved “exceeding abilities,” and 3% involved illness.⁸⁴

A number of studies have attempted to quantify the mortality rate of various activities in the mountains, including mountaineering. One review claimed that, in the United States, the mortality rate per 100 participants was 0.6 for mountaineering and 0.2 for hang gliding.⁸⁵ The number for mountaineering is not substantiated by any data or reference, is not credible, and is certainly far too high. A New Zealand study estimated a fatality rate of 1.9 per 1000 climber-days in Mt Cook National Park, with a large variation between high-risk areas (6.5 per 1000 climber days) and low-risk areas (0.3 per 1000 climber-days).⁴³ A study of climbing fatalities on Denali (Mt McKinley) estimated 3 climber deaths per 1000 summit attempts.⁴⁵ Fatality rates of the world’s highest mountains generally increase with increasing altitude.³⁰

For more information about avalanche risks, please see Chapter 2.

Injuries and Illnesses in Mountain Rescue Victims

There are many published studies of mountain rescue victims. A Scottish study of 622 callouts comprised 333 victims,²⁶ and there were 57 fatalities. Of the living victims, 78% had traumatic injuries, 8% had major trauma, 4% had spinal injuries, 8% had nontraumatic medical problems, and 14% were cold or exhausted. The author concluded that mountain rescuers provide “an advanced level of care” for many victims. Another study, which comprised the entire United Kingdom, showed a preponderance (75%) of rescue casualties due to “hillwalking,” with more than one-half of the injuries affecting the lower extremities.⁵⁰

A study of mountain search and rescue victims from three national parks in the Canadian Rockies found 317 emergency operations that involved 406 persons over a 4-year period.⁸³ Of these incidents, 44% involved hikers, and 50% were the result of “slips and falls.” About 60% of victims were injured. Injuries to the extremities accounted for 68% of the injuries. There were 40 fatalities; 45% were caused by avalanches, and 28% were caused by slips and falls.

A study of wilderness search and rescue in New England looked at 321 incidents that involved 457 victims, 57% of whom were hiking at the time of the incident.¹⁹ Injuries were involved in 39% of the rescues, and 40% involved lost and missing persons. The author noted that a rescuer was injured during 2.5% of the rescues.

A study of climbers on difficult routes in the Sierra Nevada in California found 215 mountaineering accidents in a 5-year period.⁴⁶ Acute mountain sickness or hypothermia was noted in 104 patients. There were 17 deaths, most commonly as a result of head injuries. There were 94 injuries involving the ankle and the distal tibia.

Preventive Decision Making

Risk Reduction

Technical rescue, especially technical self-rescue, is often difficult and sometimes dangerous. It may present impossible challenges, with the result that an ill or injured person may not survive. The best strategy is to prevent the need for rescue.

Proposed wilderness trips and mountain rescue missions should be examined carefully to ensure that the risks are within tolerable limits. In aviation, this is formalized with the use of rules and especially checklists that cover multiple aspects of a proposed flight. Tolerable limits in commercial aviation are very strictly defined, and the tolerance of risk is extremely low. In mountaineering, there may be a high level of unavoidable risk. The acceptable risk varies with the purpose of the trip or mission. A recreational rock climb has a very low acceptable risk, whereas an expedition to a remote unclimbed peak or a military mission in technical terrain may have a much higher level of acceptable risk.

Things to be considered before approving a proposed trip or mission include whether the abilities, training, and experience of the participants are adequate to meet the demands of the proposed operation. Participants should have an adequate level of fitness and technical skills to complete the operation safely. Unless there is only one participant (i.e., a solo climb), it is important that participants be able to function as part of a team. This may require special training, ideally with the individuals who will be their teammates on the operation. Interpersonal skills—especially the abilities to communicate and to get along well with others—may be crucial to both prevent and solve problems that occur during the trip.

The acceptable level of risk should be decided before the trip or operation begins. All participants should agree regarding this acceptable level. As problems arise, proposed solutions should be examined in the light of acceptable risk. Only in extreme circumstances should the level of acceptable risk be adjusted during the operation.

One key to reducing the risk of injury or illness is to establish and adhere to a culture of safety. Aviation operations provide lessons regarding how to establish and maintain a culture of safety. Aviation takes place in a highly technical environment in which one small mistake can be fatal. The high degree of safety in modern aviation, especially commercial aviation, is due in large part to the enforcement of a culture of safety. Every procedure that occurs during activities in technical terrain should be scrutinized to make sure that it does not introduce unnecessary risks. For example, climbers should check the security of each other’s climbing harnesses and tie-ins before climbing or descending, no matter how experienced the climbers. It is best if the team also agrees to standard procedures, such as always tying in to the rope the same way; this makes deviations from safe procedures less likely to occur and easier to spot when they do.

The aviation industry depends heavily on the use of checklists. This innovation has allowed commercial aviation, which is an inherently hazardous activity, to achieve low levels of risk to the traveling public. Because flying is a well-characterized activity, the decision process can be successfully characterized. Variables (e.g., weather, aircraft maintenance, flight crew training) and flight crew fitness factors (e.g., rest, prohibition of the use of alcohol and other drugs) can be quantified and acceptable limits established. The decision of whether to launch a flight or not is tightly regulated.

Parameters of wilderness operations are not as well characterized or regulated as those of aviation, but many aspects can be characterized. Checklists that address equipment and its use are underused. For example, climbers can use checklists to guide their use of climbing harnesses, rope systems, and other technical aspects of operations. Checklists are commonly used by organized rescue groups to inspect individual systems, such as anchors, knots, the rigging of litters, and communications.

Another example from the aviation industry is the use of redundancy and backup systems. No commercial aircraft takes off with a single working altimeter. Although weight restrictions in wilderness operations often make the use of redundancy problematic, it is worth considering what would happen if each piece of equipment were to fail. Trusting one’s life to a single rope or carabiner is often necessary in climbing; however, during an organized rescue, backup systems are usually standard.

There are many wilderness areas from which successful evacuation would be extremely difficult or even impossible in the case of injury or if crucial equipment is lost or damaged. Expeditions in these areas require an extra degree of care to avoid the need for evacuation, but members should also be aware of and accept these risks. Soldiers on military operations routinely accept risks that would be unacceptable in civilian life. Many expeditions in the Himalayas are now done “alpine style,” with climbers planning rapid ascents with minimal equipment, rather than in the traditional “expedition style,” with a series of camps and a chain of supplies putting climbers close enough to the summit for a 1-day push to the top. The alpine style is riskier, even with a high level of training and skill, but it can achieve goals that are impossible with expedition style climbs.

Increased risk has always been the price for pushing the envelope in wilderness travel. Ernest Shackleton allegedly advertised his famous Antarctic expedition with this unlikely description: “Men wanted for hazardous journey. Small wages, bitter cold, long months of complete darkness, constant danger, safe return doubtful. Honour and recognition in case of success.”⁸¹

Planning

Any climbing trip, expedition, or rescue mission should have a plan of operation that is determined beforehand; this is sometimes called a pre-plan. The pre-plan includes such aspects as a timeline for preparation, travel, and the achieving of objectives as well as the roles of each participant, including leadership and working groups. The plan should also evaluate potential difficulties of travel to remote areas, anticipate risks, and formulate strategies for dealing with problems. Safety culture and standard operating procedures are part of the plan. Planning should also include contingency plans.

Medical planning looks at the members of the group to address any preexisting medical conditions and to prepare for known medical risks. Medical risks include infectious diseases, environmental exposures, and preventable conditions. Medical planning also addresses the risk of injury.

Planning considers the skill sets of the participants and determines if these match the particular technical environments that are likely to be encountered and if they are commensurate with the acceptable level of risk. If some members of the group lack specific technical or medical skills, they can plan additional training and practice before departure; alternatively, at the start of the trip, members can be added who possess the necessary skills, or the decision can be made to accept a higher level of risk. It is possible to add members in support roles who do not participate fully in the expedition. Examples of supporting members include medical providers who will stay at base camp on a mountaineering expedition and contact persons who are not on the expedition but who can activate an organized rescue if necessary.

No expedition or group can include rescue experts and medical providers with the necessary skills and equipment to deal with all potential problems. The organizers will establish a balance among expertise (both technical and medical), available equipment, and level of risk. It is better to do this explicitly rather than after being surprised with problems during the expedition. Equipment that fails or that is lost cannot be replaced during a wilderness trip. Equipment for rescue or medical care must be carried if it is to be available when needed. Planning for a wilderness trip must include decisions about taking backup equipment, rescue equipment, and medical supplies.

It is important to recognize that physicians or other medical providers who are participants may not have the level of training and experience necessary to function effectively, especially in austere environments. Potential limitations include problems that are outside of the provider’s specialty area, that require special training that the provider does not possess, or that require special equipment that has not been brought. Even highly trained and well-equipped wilderness medicine experts will not be able to provide the same level of care in the wilderness that they can provide in an ambulance or hospital.

The organizers and participants should plan their response to illness, injury, or death. How will rescue or recovery be organized? Will the group stay together or be split? A good pre-plan can organize a group and increase the overall safety of the activity. Beyond self-rescue, the group should consider a plan for coordinating outside rescue if it is needed. With cell phones and satellite phones, no part of the world is completely isolated. Although some individual travelers and groups may prefer the risk of being completely on their own, most groups now have the possibility to communicate the need for outside help. The group can also delegate a support person who is not on the trip to arrange outside help if the group fails to communicate according to a prearranged plan.

Leadership

Leadership is part of the planning process and should be decided beforehand. Although small climbing groups do not necessarily need a leader, most expeditions should have one and also possibly a deputy leader. Larger expeditions may have an overall leader as well as specialized leaders, such as technical climbing leaders and those in charge of transportation, food, medical care, and so on. Organized rescue groups usually have a well-defined leadership structure. In the United States, this generally follows a system known as the Incident Command System.⁴⁷ Rescue groups also have general plans of operation that can be applied to individual missions.

Communications

To operate effectively, climbing teams and rescue teams should have a standard vocabulary that is used and understood by all members. For example, a rock climber will not start climbing until the person who is using the rope to safeguard his or her progress (i.e., the belayer) has indicated readiness to hold a fall. The technique of “readback” is used to minimize errors. The climber asks, “On belay?” The belayer answers, “Belay on.” The climber then says, “Climbing.” The belayer answers, “Climb” or “Climb on.”

Many standard vocabularies have evolved over time to be concise and to limit the potential for confusion. In aviation, each letter has a corresponding word. For example, the letters f and s can be easily confused when spoken, but the corresponding words foxtrot and sierra are quite distinct. Ground-to-air signals (signs and arm signals) and radio language are other examples of standard vocabularies that can be useful for climbers, members of expeditions, and rescue teams.

Climbers sometimes find themselves in situations in which communication has been disrupted. It can often be surprisingly hard to communicate by voice with a climber who is at the other end of a rope. Difficulties can be caused by wind, running water, or the fact that one climber has fallen into a crevasse. Radios are generally the best method of communication in such circumstances, but small climbing parties may not have radios, and radios may fail. A redundant form of communication involves using tugs on the rope to communicate. Climbers must know the system of rope signals to be used and practice it with each other in advance to avoid potentially fatal misunderstandings.

Many expeditions and most rescue operations will require the use of radio communication among members and often with outside parties. All participants should be able to use standard radio etiquette. Although there are some international variations in vocabulary, the form is relatively standard worldwide. Spare batteries should be available, and preplans should be in place in case radio communications fail. In some areas, the use of cell phones for communication is practical. Expeditions should consider carrying satellite phones in areas that do not have other reliable means of communication with external rescue resources.

In case of an emergency, if the usual means of communication are not available or have been disrupted, participants may need to give a distress signal. Special equipment (e.g., headlamps, whistles, flares) may be useful to call for help. A recognized distress signal is any signal in groups of three. The recipient of a distress call should answer with the use of the same means, if possible, so that the victim’s party knows that the distress call has been received.

Communications are covered in further detail in Chapter 96.

Decision Making in Self-Rescue

After a problem has been recognized, the group will attempt to solve it. Previous planning can help to streamline this process, and it can make the difference between a successful outcome and a tragic one. If there is an ill or injured participant who requires rescue, some or all of the other participants may be required to accomplish the rescue. Outside resources may be available in some circumstances. In some areas, rescue can be as simple as calling a helicopter; however, in most wilderness areas of the world, the initial phases (if not all phases) of rescue will be performed by others in the patient’s party. In technical terrain, it may take only a few people to lower a victim down a steep face or snow slope, because gravity can do some of the work; alternatively, it may take a large group to overcome complex technical problems. On easy terrain, it can take many people to carry a victim who is not ambulatory.

Although there should be a general pre-plan, when a rescue is about to be started, the team should agree about a specific plan of action. Time spent discussing this plan is usually time well spent, especially if there are any questions about the best response.

Improvised Searches

In organized search and rescue, the first step is often a search for the victim or victims. Searching for avalanche victims is covered in Chapter 2. On a trip with a small team that stays together, searches are not usually necessary. On larger trips and expeditions, if a team fails to arrive at a destination when expected and is unable to communicate with another team, a search will be necessary to find the missing team. This may be the first step in rescue if the missing team is stranded or if it has one or more members who are ill or injured. Search strategy is covered in Chapter 37.

Large groups can limit the need for potential searches by frequent radio contact with parties on the move or with passive global positioning system tracking. In areas with cell phone service, most newer cell phones support this application.

It is important to be aware that a search is an emergency. The more capable an individual or group, the more likely it is that there is a problem when he or she fails to arrive as expected at a destination. Experienced climbers are likely to know how long it will take them to complete a given itinerary and can overcome many unexpected obstacles. If they are overdue, it is more likely that a serious problem has occurred than when less experienced climbers are late.

Wilderness Medicine Technical Rescue

Survival of an injured person may depend on the speed of rescue and the care given during and after the rescue. Any group that is planning to travel in remote, steep, or technical terrain should have specific plans for potential emergencies, assess possible scenarios, and prepare in advance for rescues. The plan for rescue should include clearly defined leadership roles and sufficient technical capabilities. In a perfect world, there would be a plan to ensure that help would be provided promptly to anyone who needed it. Ideally, specific rescue equipment to carry out any foreseeable rescue and a medical kit to deal with any problem should be available. However, the ideal seldom occurs in the wilderness, rescue equipment can be heavy, and no medical kit can deal with all possible illnesses and injuries. Technical rescue equipment is discussed in Chapters 37 and 39.

Every technical rescue operation involves some amount of improvisation, because every rescue is different. This variability demands thought and creativity when developing a solution, and it often includes including technical rigging. Most technical rescue operations have a few basic concepts in common: anchors, descent, ascent, raising, and lowering. The ability to apply principles related to all of these concepts in low-angle, high-angle, vertical, and overhanging terrain—whether hanging or with feet planted firmly on the ground—is an essential part of the rescuer’s tool kit.

Anchors

Anchors for rescue are similar to climbing anchors except that they are implemented with the understanding that they may be subjected to loading by more than a single person (i.e., some combination of rescuers, a patient, and equipment). Rescue anchors need to be stronger than normal climbing anchors.

The simplest single-point anchor consists of wrapping a piece of webbing or rope around a “bombproof” anchor point, such as a tree or a rock. In this case, the strength of the anchor will depend on the strength of the anchor point and the connecting components, which may include webbing, rope, and carabiners.

Rope is preferred to webbing for use in rescue anchors, because it is more abrasion resistant and usually stronger. One method of anchoring a rope is to use the end of a rope that has been wrapped three or more times around a substantial object such as a tree and clipped back onto itself (Figure 38-1). This method, which is known as a tension-less anchor, provides an anchor that is as almost as strong as the rope itself.

FIGURE 38-1 Tension-less anchor.

(Courtesy Loui H. McCurley.)

A single strand of 25-mm (1-inch) nylon webbing (sling) is rated at about 18 kN (4000 lbf), whereas a single strand of 11-mm (0.4-inch) nylon static or low-stretch rope is rated at about 27 kN (6000 lbf). High modulus fibers such as aramid (Kevlar) and ultra-high-molecular-weight polyethylene (Spectra) are even stronger but offer little or no elongation (stretch). Elongation is an important part of rope-based systems: when a shock load occurs, stretch in the ropes and webbing decreases sudden impact on the anchor and on persons who are in the system. High modulus fibers increase the risk of anchor failure and injury caused by shock loading; they should only be used with great caution in rescue work.

Webbing used for climbing and mountaineering is often pre-sewn into a continuous loop. Webbing loops may be used in a basket hitch configuration (Figure 38-2) or a girth hitch configuration (Figure 38-3) around an anchor point. When using a girth hitch, care should be taken to align the load properly, as shown in the figures.

FIGURE 38-2 Webbing basket hitch anchor.

(Courtesy Loui H. McCurley.)

FIGURE 38-3 Webbing girth hitch anchor.

(Courtesy Loui H. McCurley.)

Some climbers and mountaineers prefer to use a version of 25-mm (1-in) tubular nylon webbing that is not pre-sewn. This allows for greater customization and adaptability, because it may be tied to whatever length is needed for a given situation. Ends of nylon webbing should always be joined with a water knot; this is also known as a ring bend. This and other knots are covered in Chapter 95. Spectra is a very slippery fiber that does not hold knots well, and Spectra webbing should only be used if it is pre-sewn. If Spectra webbing must be tied in an emergency situation, a pre-tensioned triple fisherman’s knot with plenty of excess tail has the best chance of holding.

When webbing is tied around an anchor point such as a tree, the most secure method is to wrap the webbing three times around the anchor and then to pull two of the strands out as clip-in points (Figure 38-4). The water knot joining the two ends of the webbing should be positioned so that it is on the back side of the strand that is left tensioned around the anchor point.

FIGURE 38-4 “Wrap three, pull two” anchor. When using tied webbing, the knot should be positioned on the back of the anchor.

(Courtesy Loui H. McCurley.)

Because a key premise of any rescue—as of medicine—is to do no harm, placing two anchors rather than one is often desirable. There are many strategies for rigging multipoint anchors. The first decision is whether one anchor will provide “backup” to the other or if the load will be shared between the two. If rigging is done so that one anchor provides backup to the other, keeping the two anchors in line with one another and the fall line—and pre-tensioning between the two, if necessary—will help prevent catastrophic swing or shock load in the event of a failure. No anchor should ever be used unless it can be reasonably expected not to fail, so in principle this should not be a problem.

Because rigging two anchors is desirable, sharing the load between the two anchors from the outset may also be a good plan; this type of anchor system is known as a load-sharing anchor. A load-sharing anchor shares the load between multiple points (Figure 38-5). One concern with a load-sharing anchor is that, unless the fall line is completely consistent, there will be times at which one or the other of the anchor points will bear most or even all of the load. For this reason, a load-sharing anchor should not be used to justify multiple weak anchor points.

FIGURE 38-5 Load-sharing anchor.

(Courtesy Loui H. McCurley.)

One method to avoid uneven loading between anchor points is to rig the load-sharing anchor so that it is allowed to self-equalize. This kind of rigging allows the load to remain distributed more consistently by multiple anchor points, even as the load moves across the fall line. The risks of self-equalizing anchors are often debated in climbing and rescue circles. If a sling that is too long is used to connect the anchor points, the failure of one of the points could create an excessive fall distance and a potentially high-impact load. Another useful technique is to use individual anchor slings (e.g., rope) with some force-absorbing qualities (e.g., elasticity) to extend outward from the anchors to a very short Spectra sling. The slipperiness of Spectra allows for better equalization of the load. In addition, using a short sling helps to prevent a long fall.

With any multipoint anchor system, the angle formed by the lines between the two anchors should be as acute as possible. As the angle increases, so does the amount of force placed on each anchor point. Generally, the maximum angle should be 90 degrees. The angle should never exceed 120 degrees. If circumstances demand the use of an angle of more than 90 degrees, increased forces at the anchors, at the anchor line terminations, and on other components in the system should be taken into account.

When an anchor is attached to a structure that clearly has more than adequate strength, it is still advisable to anchor each line separately by using two slings or two connectors, even if both slings or connectors go around the same anchor point. Anchors should ideally be unquestionably reliable, be placed so that the rescuer can maintain a working position without difficulty, and be designed so that rescuers can connect to or disconnect from the rope system in an area in which there is no risk of a fall from a height.

Descent

The term pickoff refers to rescuing a person who is in technical terrain, usually on a cliff. The person may be an injured climber or a climber who is uninjured but who needs to be removed from a vertical or near vertical setting, usually as a result of his or her inability to self-rescue safely or in a timely fashion. Basic descending techniques provide the foundation for a rescue pickoff. Equipment necessary for descent includes an anchored rope, harness, and descending device.

Although using a harness can be avoided in some terrain with the dulfersitz rappel technique, this method of descending is useful for very short descents or in desperate circumstances; it involves wrapping the rope between the legs and around the body to provide friction (Figure 38-6). This technique can be painful to use, even under one’s own weight, and it is certainly not sufficient when carrying another person. Another method, the arm wrap (Figure 38-7), is less uncomfortable, but it is also less effective, and does not provide enough friction to be used in vertical terrain.

FIGURE 38-6 Dulfersitz rappel.

(Courtesy Loui H. McCurley.)

FIGURE 38-7 Arm-wrap rappel.

(Courtesy Loui H. McCurley.)

The Swiss seat harness (Figure 38-8) is a better means of connecting oneself to a rope. It requires about 6 m (21 feet) of webbing, depending on the size of the person. It is much more secure than a simple diaper-style improvisation. Although this method of tying a harness is not easy to remember, the Swiss seat can be mastered with a little practice.

FIGURE 38-8 “Swiss” seat harness; a tied harness using webbing.

(Courtesy Loui H. McCurley.)

Any descender that provides sufficient friction on the rope may be used. Figure-8 descenders are common, but have the major disadvantages of not providing sufficient friction for a heavy load and of twisting and kinking the rope. Figure-8 descenders can be double wrapped to increase friction (Figure 38-9). Brake racks are commonly used by cavers and rescuers. Manipulating the bars allows for the easy adjustment of the amount of friction; the straight-line design does not twist the rope. In Europe, auto-locking devices such as the Prism and the I’D have become popular because they help to prevent catastrophic failure. Some professional rescue teams use the Brake Tube, which facilitates knot passes. Another popular device that allows for the easy adjustment of friction is the Scarab.