Chapter 23 Improvised Medicine in the Wilderness

For online-only figures, please go to www.expertconsult.com

At the heart of wilderness medicine is improvisation, a creative amalgam of formal medical science and commonsense problem solving. Medical emergencies can arise at any time in wilderness settings; clinicians in these environments often encounter situations requiring their interventions with little or no medical equipment at hand. Even when they have supplies, as they might if they are the designated providers for a wilderness group or part of a search and rescue team, clinicians venturing into a wilderness environment will soon discover that some improvisation may still be necessary. When improvising medical equipment, consider whether it (1) will accomplish the purpose for which it is intended, (2) is practical, or (3) may worsen the situation.²³ Improvisation encompasses many variations, is governed by few absolute rights and wrongs, and is limited more often by imagination than by personnel or equipment.

As Louis Pasteur reportedly said, “Chance favors the prepared mind.” This chapter is in no way exhaustive but suggests the types of improvisations that may be possible in wilderness or remote settings. Of note is that all these methods have been tested, with many appearing in peer-reviewed literature. Although some of the improvisations, such as transportation methods, border on first aid, they are an integral part of the complexities of remote medical care.

Vital Signs

Height

To measure an ambulatory patient’s height, use marks in 0.5-cm (or 0.5-inch) increments on any rigid, vertical surface, such as a wall or the side of a doorway. For infants and bedridden patients, put similar marks along the sides of stretchers or beds. Height approximations can be made with marks 0.25 m (or one foot) apart. To estimate a sitting adult’s height, measure the distance (in centimeters) from midsternum to the extended middle finger.

⁷⁹

Alternatively, doubling the longest measurement from midsternum to the tip of the patient’s third finger produces a very accurate height estimate.⁴⁵

A relatively accurate way to obtain an adult patient’s weight is to use weight estimates by experienced health care workers. Estimates by paramedics, for example, have been shown to correlate well with the patients’ actual weights in adult cardiac arrest victims.⁴⁹ Weight estimates of children can be more difficult. Parents can estimate their child’s weight (ages 1- to 11-years-old) within 10% of the measured weight only 78% of the time. This is better, however, than what is estimated by the Broselow tape, which is within 10% of the measured weight only 61% of the time and is less accurate as children get older. In less-developed countries, the Broselow tape underestimates children’s weights.^4,^8,^35,⁴⁸ All other forms of guessing a child’s weight, including the Argall, the Advanced Pediatric Life Support, and the Best Guess methods, perform poorly.⁴³ If the parents are not around, use the following formula:

Pulses in Infants

The typical method of deciding whether an infant has a pulse requires providers to palpate the pulse. This means knowing where and how to locate it, even if it is barely (or not) palpable. Palpating an infant’s pulse, especially when the child is critically ill and a decision must be made immediately about whether to begin resuscitation, can be very difficult. However, determining infant cardiac activity is quickly and easily done by simply placing one’s ear against the infant’s chest wall and listening for heart sounds (Figure 23-1).³⁸

FIGURE 23-1 Direct precordial auscultation.

Radial Pulse and Trauma Prognosis

Tachycardia is a much more reliable sign of hypovolemia than is blood pressure (BP). In trauma patients who are 18 to 50 years old without a head injury, a weak radial pulse indicates a markedly increased mortality (29%) compared with only 3% of patients with a normal pulse, as well as a high likelihood that the victim will require intubation and intensive care unit admission. Patients with no radial pulse are usually moribund.⁵¹

Blood Pressure

Research has shown that the “ability to obtain a blood pressure measurement in an austere environment is often limited by time constraints, equipment availability, and noisy conditions.”⁵¹

Blood Pressure Without a Cuff

Pulse characteristics are an unreliable sign—and “should be used only as a last resort.”⁵¹ Originally, the advanced trauma life support (ATLS) course taught that systolic blood pressure can be estimated from whether radial (>80 mm Hg), femoral (70 to 80 mm Hg), or carotid (60 to 70 mm Hg) pulses are palpable. This tends to overestimate the patient’s blood pressure. Although the radial pulse always disappears before the femoral, which always disappears before the carotid, most patients’ actual BP is lower than that predicted by these guidelines. But that, by itself, is useful information in a crisis.¹⁵

Although an exact BP measurement cannot be obtained, patients with cool extremities compared with those of other patients have hypoperfusion. This can be localized to one extremity, but if it is located in multiple extremities—especially in both an arm and a leg—checking palpable temperature is an effective diagnostic technique. These patients have lower cardiac indexes, lower pH, lower bicarbonate levels, lower mixed venous oxygen saturation, and higher lactate levels.⁴² A cold or dusky sole of a neonate’s foot can indicate one or all of the following: hypothermia, hypoxemia, or hypotension.¹⁴

Blood Pressure Without a Stethoscope

Because it may be hard to auscultate BP when transporting patients by air or in a noisy ambulance, palpate the systolic pressure. If done carefully, this method is as accurate as using a stethoscope. Alternatively, use a pulse oximeter by obtaining a good waveform on a finger, inflating the sphygmomanometer until the waveform disappears, and then slowly deflating the cuff until the waveform reappears. The cuff measurement that reappears is the systolic pressure.⁵⁰

Wrist and Calf Blood Pressure Measurements

To be accurate, a BP cuff must be the correct size for the arm. It should cover two-thirds of the length of the upper arm. A BP cuff that is too small causes an abnormally high BP reading; one that is too large results in an abnormally low reading. If you do not have a cuff that fits the arm correctly, move it to a location where it fits properly.

Place a BP cuff on the patient’s forearm (Figure 23-2) or ankle (Figure 23-3) to obtain better access during patient transport (1) with very obese patients on whom the standard adult cuff is too small, (2) for adults when only a child’s-size cuff is available, (3) to avoid periodically occluding an arteriovenous fistula (e.g., dialysis patients) or intravenous (IV) line, (4) or to avoid compressing an area with traumatic injuries.

FIGURE 23-2 Blood pressure cuff on forearm.

FIGURE 23-3 Blood pressure cuff on calf above ankle.

BP cuffs at these sites produce the same or nearly the same mean and diastolic pressure readings, but the systolic pressures vary. Use the mean BP with a forearm or calf BP cuff. (Calculate this by multiplying the diastolic pressure by 2 and adding the systolic pressure. Then divide the result by 3. Alternatively, take one-third of the difference between the systolic and the diastolic pressures, and add this number to the diastolic pressure.)⁴⁰

Measuring Length, Area, and Volume

A way to most accurately estimate the sizes of wounds is to measure them against the clinician’s own body parts. Table 23-1 gives approximate lengths and areas for upper extremity body parts to use with measurements corresponding most closely with adult white men. Because body sizes vary greatly, especially between men and women, practitioners should measure these sites on their own bodies before using them to measure patient lesions.

TABLE 23-1 Clinical Measurements Using Body Parts *

Approximate Length	Measurement Site(s)
1.3 cm (0.5 inch)	Finger width: greatest width of the distal phalanx of the small finger
2.5 cm (1 inch)	Phalanx: length of the middle phalanx of the small finger (Figure 23-4)
	Thumb: width of thumb at the interphalangeal joint (Figure 23-5)
	Span: when opening the hand and spreading the fingers widely, from the tip of the thumb to the tip of the index finger (Figure 23-6)
3.8 cm (1.5 inch)	Grasp: the greatest diameter of the circle formed with the thumb and index finger (Figure 23-7)

* Some of these measurements were suggested by White J, editor: Handbook of Indians of Canada, published as an appendix to the Tenth Report of the Geographic Board of Canada, Ottawa, 1913, pp 280-281. http://faculty.marianopolis.edu/c.belanger/quebechistory/encyclopedia/MeansofMeasurementbyIndians.htm.

Adapted from Iserson KV: Improvised Medicine: Professional Treatment with Scarce Resources. McGraw-Hill (in press).

FIGURE 23-4 Phalanx (2.54 cm [1 inch]).

FIGURE 23-5 Thumb (2.54 cm [1 inch]).

FIGURE 23-6 Span (15.24 cm [6 inches]).

FIGURE 23-7 Grasp (3.81 cm [1.5 inches]).

Standard measurements, in centimeters or in inches, can be made on personal medical equipment, such as the metal earpieces of a stethoscope (Figure 23-8), a reflex hammer handle, penlights, and scissors.

FIGURE 23-8 Stethoscope marked to measure lengths.

Volume Measurement

Volume measurements are used to determine the outputs of urine, blood, and other secretions, and to measure fluids and medications. To obtain an accurate volume measurement, use kitchen measuring devices or food containers that have their volume indicated on the label. Generally, they only need to be cleaned of food or whatever else they previously contained. Sterilize the measuring container only if the specimen also has to go to the laboratory or will be used to measure injectable medications. Measuring containers for items that will be taken orally need to be “potable clean,” meaning that one could safely drink from them.

Improvised Diagnostic Equipment/Supplies

Stethoscopes

Ear to Patient

If no other option is available, use the method that was common before Laennec invented the stethoscope: put one ear directly against the chest, heart, or abdomen. The sound quality will not be as good as through a stethoscope, but one can get a general idea of cardiac rhythm, abnormal chest sounds, and bowel sounds. Putting one’s ear on an infant’s chest is the fastest and most accurate method for assessing the presence of cardiac activity.

Improvised Standard Stethoscopes

Laennec-type stethoscopes can easily be fashioned by using rolled paper or, even better, a hollow wooden tube, such as bamboo. The cardboard tube from toilet paper or paper towels also works well. When one end is placed on a patient’s chest and the clinician’s ear is at the other end, one can hear the heartbeat clearly. This, of course, depends on ambient noise and the patient’s body habitus. Use any hollow tube, including short lengths of garden hose, ivory or wood tubes, and metal pipes, as a monaural stethoscope.

A simple way to construct a slightly more sophisticated stethoscope is to attach a funnel to two pieces of tubing as shown in Figure 23-9. The juncture of IV tubing works well as a T-tube connector. Put the tube ends directly in your ears, or fashion earpieces as described in Stethoscope Earpiece, later.

FIGURE 23-9 Improvised stethoscope.

Precordial Stethoscope

One very useful monitor during patient transport or procedural sedation is a precordial stethoscope. Taped to the patient’s chest, a precordial stethoscope provides the clinician with continuous assessment of the patient’s audible heart rate and rhythm and breath sounds. Only one earpiece is normally used so that the caregiver can also monitor everything around him or her. In adults, place the stethoscope over the midsternum, in the suprasternal notch, in the perilaryngeal area, or in the axilla. In infants, place the stethoscope to the left chest so that both the heartbeat and breath sounds can be heard. Several improvised methods will produce a workable precordial stethoscope.

The quickest way to make a precordial stethoscope is to attach a piece of rubber tubing (that goes in the clinician’s ear) to the top of a screw-top plastic bottle that has a narrow, tapered opening, such as a ketchup/mayonnaise dispenser. Alternatively, cut off the tapered end of a rubber bulb suction syringe or stethoscope head, if one is available.^16,⁷⁷

A slightly more complex method is to make a precordial stethoscope from a 20-mL syringe, a 3-way stopcock, IV tubing, and an earpiece (Figure 23-10). Cut the 20-mL syringe 2.5 cm (1 inch) from the infusion end (see Figure 23-10, A). Then, smooth the edges with a file, and place adhesive tape around the cut end of the syringe. Remove the plunger’s rubber sealer (see Figure 23-10, B), cut a large hole in its center (see Figure 23-10, C), and insert the rubber piece into the small piece cut off the syringe barrel (see Figure 23-10, D). After connecting this to a three-way stopcock, connect the stopcock to IV tubing (or other tubing) and then to an earpiece (see Figure 23-10, E).³²

FIGURE 23-10 Improvised precordial stethoscope.

Esophageal Stethoscope

Another way to simultaneously monitor respirations and cardiac rhythm in austere situations and during transport is to use an esophageal stethoscope. Make an esophageal stethoscope from a rubber glove, a nasogastric (NG) tube, suture, and a regular stethoscope. Cut a finger off of the glove, and tie the finger over the end of the NG tube (Figure 23-11). Remove the bell from the stethoscope. Pass the NG tube approximately halfway down the esophagus, and connect the proximal end to the end of the stethoscope. The NG tube can also be passed through the nose.¹⁷

FIGURE 23-11 Making an esophageal stethoscope.

Hearing Aid

When necessary, substitute a stethoscope for a patient’s hearing aid during an examination. Put the earpieces in the patient’s ears and talk into the diaphragm. Unfortunately, this only works, as do hearing aids, for patients with specific types of hearing loss.

Stethoscope Earpiece

To replace a stethoscope earpiece, use the nipple from a baby bottle or pacifier, or the rubber bulb from a medicine or an eye dropper (Figure 23-12). Make the normal pinhole opening in the nipple slightly larger, and tie the nipple in place on the stethoscope. Cut the nipple so that only the distal 1 to 2 cm (0.4 to 0.8 inch) of the rubber piece is used.⁴⁰

FIGURE 23-12 Earpieces for a stethoscope.

Improvised Treatment Equipment/Supplies

Gowns, Gloves, Masks, Booties, and Goggles

Dressings and Bandages

Dressings go directly on wounds and can be adherent or nonadherent, wet or dry, and absorbent or not. Dressings are often sterile. Bandages cover dressings, can hold them in place, and place pressure on the wound. Although most clean fabrics can be used as dressings or as bandages, do not use paper products because they disintegrate when wet and leave fibers in the wound.

Dressings

Most clean, closed wounds do not need a dressing. Wounds without dressings permit easier inspection for infection or dehiscence, eliminate a moist, possibly anaerobic, space over the wound, and make it much easier to keep the wound clean. Have the patient clean the wound with soap and water.

Dressing Material

If a dressing is being used to help absorb serosanguineous drainage, to keep the wound moist after small plastic closures, or to keep air off an open wound to lessen pain, any absorbent material may be used. A menstrual pad works well to absorb exudates, and more absorbent cotton fabrics can also be useful. If nothing else is available, use moss, especially sphagnum (peat) moss, a traditional absorbent dressing. Make nonadherent dressings from sheer synthetic materials, such as parachute cloth or nylon stockings. Use any clean piece of plastic sheeting, such as a plastic bag, to fashion an occlusive dressing for open-chest wounds. Using clean, rather than sterile, dressings will rarely affect the incidence of infection.

Bandages

Bandages hold dressings in place. If there is a dressing, there is no need for a bandage. The most expedient bandages are torn from expendable pieces of cloth—often clothing. If no cloth bandage is available, use duct tape to secure a dressing after first shaving the area to help the dressing adhere and reduce pain on removal. Poke holes in the tape (especially thick adhesives, such as duct tape) to reduce moisture and allow fluids and sweat to escape. Clean the skin with soap and water or alcohol to remove oils. To make an adhesive dressing, cover a small square of dressing with a piece of tape. If you need to see the wound but still want it covered, make a transparent bandage from clear plastic wrap (e.g., Saran Wrap) or a piece of clear plastic bag with its edges affixed to the skin with tape or cyanoacrylate glue.⁴⁰

A pressure bandage over dressings, used when there is significant seepage or concern about hematoma development, is most easily constructed from an elastic bandage, a bungee cord (use only over fabric stiff enough to distribute the cord’s force), or the elastic from a piece of clothing or equipment.

Syringes, Needles, and Intravenous Equipment

Venipuncture Tourniquet

A rubber glove (sterile or unsterile, but “stretchy”) works well as a venous tourniquet when starting IV lines or drawing blood. Even better, cut the wrist portion off of a surgical glove and slip it over the arm (or an infant’s head).⁶⁰

Needles

When necessary, use needles for injection as IV needles. Note, however, that they may be more difficult to thread into a vein, because injection needles tend to puncture the vessel wall rather than slide in as does the plastic-coated needle on a catheter. Take care when securing an injection needle, using an arm board or generous bandaging so that the needle does not perforate the vessel.

Saline Locks

To quickly make a saline lock, slip the rubber end of the plunger from a 2- or 3-mL disposable syringe over the end of an IV catheter (Figure 23-18). This also works on a straight needle if it needs to be used as an IV catheter. Simply fill the catheter with saline (or heparin) as would normally be done.⁴⁰

FIGURE 23-18 Improvised saline lock.

Intravenous Tubing

One way to adjust IV flow rates is to wrap a small piece of malleable metal (e.g., heavy aluminum foil) around the tubing. Tighten it to the tubing to achieve the desired flow rate.

Pressure for Intravenous Fluids/Blood Bags

Apply external pressure to IV bags so that, especially when patients must be transported, the pressurized IV bag can simply lie on or next to the patient. Ways to increase the IV or blood bags’ external pressure include inflating a blood pressure cuff around them, and wrapping them with an elastic bandage, a belt (“stretchy” if possible), nylon stockings, a rope, or similar materials. The IV bag can also be placed under an adult patient; body pressure keeps the IV flowing.

Suture Needles

To make a “swaged” suture needle from a hypodermic needle, first pass the suture through the needle from the sharp end. When the end of the suture appears, hold it in place and break off the hub by repeatedly bending it (Figure 23-19). Then pull the suture through the needle so that only a small amount remains within the needle. Finally, crimp the “hub” end of the needle to fix the suture in place.³¹ Do this either at the patient’s bedside or prepare several in advance, wrapping the sutures around a piece of cardboard and autoclaving them en masse.⁷⁵ Newer safety needles may make this process difficult.

FIGURE 23-19 Improvised swaged suture.

Scalpels

When necessary use any clean, preferably sterile, sharp object to perform surgical procedures. Nearly any piece of metal can be sharpened sufficiently to serve as a scalpel. Honing the entire length of a blade to surgical sharpness takes special metal, tools, and expertise. One option is to start with a straight razor or a cutting knife and sharpen it as well as possible before sterilizing it.

Make a scalpel from a common multi-blade disposable razor by first carefully separating a blade from its plastic holder. Use pliers or a similar tool to bend one end; the blades pop out (Figure 23-20, online). Then put a few drops of cyanoacrylate glue on both the blade and the utensil/holder; the blade can be affixed along the metal blade of a butter knife, the handle of a spoon, or similar items that can be easily held and manipulated during a procedure. The blade should extend over the side of the handle and be parallel to the other side for better control of the scalpel. Wait about 10 minutes for the cyanoacrylate glue to dry.

FIGURE 23-20 Disposable razor blade fashioned into scalpel. Note blade cemented to bottom of spoon handle.

Skin Hooks

The best way to handle wound tissue with the least amount of trauma is to use skin hooks. To improvise a skin hook, grasp the tip of a small-gauge needle with a utility tool and bend it into a U-shaped curve (Figure 23-21). Then attach it to a 1- to 10-cc syringe, which serves as a handle. Alternatively, unbend a safety pin so that the two “limbs” on each side of the spring form a straight line. Then bend the sharp end into a U-shape. Sterilize them before use.²⁴

FIGURE 23-21 Improvised skin hooks.

Retractors

Self-retaining retractors make procedures easier when working alone or with inexperienced assistants. To make these retractors, bend stiff metal rods into the form shown in Figure 23-22. Use 3-mm rods for minor surgery and heavier rods for major wounds.³⁷ If made from lighter material, such as paper clips, they can be used on more delicate tissues.

FIGURE 23-22 Lightweight self-retaining retractor.

Tweezers

Fashion tweezers to remove foreign bodies or for surgical procedures from pieces of thin metal strips, such as the metal straps that secure boxes for shipping. If folded with a slight bulge in the end they are less likely to break at the fold after repeated use (Figure 23-23). Use a file to make as fine of an end as you need.

FIGURE 23-23 Surgical “pickups.”

Cleaning and Reusing Medical Supplies and Equipment

Much modern medical equipment is labeled as “disposable.” When resources are scarce, this is a luxury that cannot be sustained. On the other hand, is it safe to reuse this equipment? Caregivers do not want to put patients at risk by introducing infections from previously used equipment or by using malfunctioning equipment.

When trying to guide health care professionals in their reuse of single-use devices, many major governing bodies cannot agree on their recommendations. The United States, however, has a consistent policy among several agencies. According to the U.S. government’s report, equipment and supplies “will be rationed and used in ways consistent with achieving the ultimate goal of saving the most lives (e.g., disposable supplies may be reused).”³⁴ Other federal agencies concur, noting that whether medical equipment should be reused depends on the type of equipment and the disinfection method used. ^47,^12,⁴⁶

Risk Stratification

The infection risk that medical equipment poses to patients differs and can be stratified according to the equipment’s use, as follows:⁶⁷

• High-risk items (sterilization required) that come into close contact with breaks in the skin or mucous membranes or are introduced into a normally sterile body area. These include surgical instruments, needles, and urinary or other catheters.

• Intermediate-risk items (disinfection required) that come into close contact with mucous membranes or are items contaminated with particularly virulent or readily transmissible organisms. Examples are respiratory equipment (including laryngoscope blades), endotracheal and tracheostomy tubes, and oropharyngeal and nasal airways.

• Low-risk items (cleaning required) that only come into contact with normal, intact skin. These include stethoscopes, stretchers and wheelchairs, other physical examination equipment, and electrocardiography and electroencephalography leads.

Cleaning

Cleaning must be done so that equipment can be properly disinfected or sterilized. Cleaning removes visible dirt or secretions, including dust, soil, large numbers of microorganisms, and organic matter (e.g., blood, vomit) on which microorganisms grow.⁶⁷ Immediately after use, clean equipment by washing it thoroughly with warm water without soap. Then brush it thoroughly with warm water and soap, rinse with water, and dry completely. Clean surgical instruments with a small brush, such as a soft toothbrush. Leave scissors and forceps open during drying.⁴⁰

Disinfection

Disinfection reduces the number of microorganisms to a level that is not harmful to health, although the process does not necessarily kill or remove all microorganisms or bacterial spores.⁶⁷ The CDC recognizes three levels of disinfection: high, intermediate, and low.¹²

• High-level disinfection using a chemical germicide, including bleach and ethyl alcohol, kills all organisms, except when there are high levels of bacterial spores.

• Intermediate-level disinfection kills mycobacteria, most viruses, and bacteria with a chemical germicide registered as a “tuberculocide” by the U.S. Environmental Protection Agency.

• Low-level disinfection kills some viruses and bacteria with a chemical germicide, such as soap.

Boiling

The best way to disinfect equipment in austere environments is to boil it (100° C [212° F] for 10 to 30 minutes at sea level) in clean water, with or without soap. The time starts when the water has come to a full boil. The temperature at which water boils decreases at higher altitudes, so a longer boiling time will be required. In theory, the time should be increased by 5 minutes for each 300-m (1,000-foot) rise in altitude. For example, at 4000 m (approximately 12,000 feet) above sea level, water boils at 86° C (187° F), so boiling for 60 minutes or longer is required for disinfection. A way to increase the disinfectant effect of boiling is to use “double boiling.” Boil the instruments for 30 to 40 minutes. Let them cool, and then boil for another 30 to 40 minutes.³⁶ This process kills all organisms except for certain bacterial spores.

Alcohols

Alcohols (e.g., methanol, ethanol, and isopropanol) have good activity against bacteria and viruses so long as the equipment first has been cleaned—or, at least, after all the visible surface dirt has been removed from the area to be disinfected. Use 70% or greater concentrations, and have the equipment in contact with the alcohol for 10 minutes or longer; the longer the contact time the better. To prepare a 70% ethanol solution, add 8 parts 90% ethanol to 2 parts water. To prepare a 70% isopropanol solution, add 7 parts standard isopropanol to 3 parts water.⁷¹

Povidone-Iodine

Povidone-iodine (PVD-I; Betadine) may be used for disinfecting instruments. Although exact information about this is sketchy, studies seem to support its use. Use 1 part 10% povidone-iodine solution to 3 parts water for 15 minutes.⁷¹

Disinfecting Specific Items

“Sterile” Dressings

Clean and disinfect cloth for dressings by boiling it in water for 15 minutes or saturating it in alcohol.

Syringes and Needles

It is not possible to clean the interior of disposable syringes and needles well enough to use them safely on another patient. Although syringe reuse is a common practice throughout the world, it is so dangerous that it negates any good that medical treatment produces. Only when no other option exists should cleaning and reusing syringes be considered. If that is the case, the best option is one that the U.S. governmental agencies recommend for needles and syringes potentially contaminated with human immunodeficiency virus. That is, they should be thoroughly cleaned and then immersed in full-strength bleach (5.25% sodium hypochlorite).⁶⁴

Single-Use Needle on Same Patient

With proper precautions, single-use needles can be used multiple times on the same patient. For example, diabetics routinely reuse the same syringe for up to a week. They do this by keeping the needle clean, storing it in a clean container, and ensuring that no one else uses it.

Surgical Instruments

Use alcohol or, if the equipment does not contain plastic or polymers, acetone to chemically sterilize sharp or delicate instruments. Following this soak, rinse them in hot, sterile water and let them dry.⁶⁶ Surgical instruments without a fine tolerance or sharp edges, such as mosquito clamps, towel clips, and large needle holders, may be disinfected in boiling water.⁶⁶ If you do not mind that sharp instruments will lose their edge, metal can be sterilized by holding it over a flame or, even better, by placing the instrument in a pot with a small amount of isopropyl alcohol (enough to create a small pool on the bottom of the pot). Ignite the alcohol, and allow it to burn out, which takes about 5 to 10 minutes. The alcohol burns without leaving significant carbon residue. These techniques may be used when sterilization is really needed or when available resources or time do not allow for disinfection by boiling or soaking in alcohol.⁴⁰

Improvised Airway Management

Because establishing or maintaining a patient’s airway is the most fundamental lifesaving skill, clinicians must be able to do this despite limited or unusual equipment.

Positioning for Safe Airway

Preventing aspiration may be all that is necessary in many patients to maintain an airway, especially in the presence of copious secretions or vomiting. Use the “rescue” or “recovery” position—with the patient on his or her side with face aimed down (Figure 23-24). If possible, elevate the patient’s feet so that he or she is in the head-down position.

FIGURE 23-24 Rescue/recovery position.

Opening the Airway

Chin Lift/Jaw Thrust

Elevating the chin is often the easiest method of maintaining an open airway (Figure 23-25). For many patients with diminished consciousness, this is often all that is needed to keep the airway patent. If a cervical spine injury is suspected, the alternative is to push the jaw forward from the mandibular angles.

FIGURE 23-25 Chin lift.

Head Turn

When cervical spine injury is not a concern, turning the patient’s head to one side is a simple but rarely used procedure to open an airway. In patients with significant amounts of redundant tissue in the pharynx and hypopharynx this procedure usually improves airflow.

Positioning the Tongue

If a suspected cervical spine injury prevents head repositioning or the patient’s tongue still blocks the airway after positioning the head, grasp the tongue with gauze and pull it forward. If this opens the airway (it usually does), put a heavy (approximately 2-0) suture vertically through the tip of the tongue in the midline (Figure 23-26), or use a wire fishing line (or similar material), or safety pin (Figure 23-27). This placement avoids significant bleeding. Initially, have someone hold the suture; if needed long-term, pass it through the skin of the lower lip and tie it. Do not use a clamp or forceps that “may in the excitement of the moment be so firmly applied as to nip a piece out of the tongue.”²⁵ Physicians, surgeons, and anesthetists have used these methods since at least the 19th century without complication.⁴⁰

FIGURE 23-26 Suture used to hold the tongue out.

FIGURE 23-27 Safety pin holding the tongue out.

Nasal Airways

One of the most useful pieces of airway equipment, a nasal airway, or “trumpet,” is easy to improvise. Put a safety pin through the end of any soft piece of rubber tubing (e.g., Foley catheter, uncuffed endotracheal tube, radiator hose, solar shower hose, siphon tubing, or inflation hose from a kayak flotation bag or sport pouch) that is the appropriate size for the patient’s nose (Figure 23-28). In adults, the tube’s length beyond the safety pin equals the length from their nares to the meatus of their ears (11 to 13 cm [4.5 to 5 inches]).¹⁰ This “Goldman’s airway” can be made to fit any nose. Consider using nasal airways bilaterally. When placing a nasal airway, lubricate it well, and pass it along the floor of the nose (straight back, not cephalad).⁴⁰

FIGURE 23-28 Goldman’s nasopharyngeal airway.

Mouth-To-Mouth Rescue Breathing Barrier

A glove can be modified and used as a barrier shield for performing rescue breathing. Cut the middle finger of the glove at its halfway point and insert it into the victim’s mouth. Stretch the glove across the victim’s mouth and nose, and blow into the glove as if inflating a balloon. After each breath, remove the part of the glove covering the nose to allow the victim to exhale. The slit creates a one-way valve, preventing backflow of the victim’s saliva (Figure 23-29).

FIGURE 23-29 An improvised cardiopulmonary resuscitation (CPR) barrier is created using a latex or nitrile glove.

Surgical Airway (Cricothyrotomy)

Cricothyrotomy—the establishment of an opening in the cricothyroid membrane—is indicated to relieve life-threatening upper airway obstruction when a victim cannot be ventilated effectively from the mouth or nose and endotracheal intubation is not feasible. This may occur in a victim with severe laryngeal edema or with trauma to the face and upper larynx. Cricothyrotomy may also be useful when a person’s upper airway is obstructed by a foreign body that cannot be extracted by abdominal thrusts or direct laryngoscopy.

To perform a cricothyrotomy, cut a hole in the thin cricothyroid membrane and place an endotracheal tube or, in austere circumstances, a suitable hollow object into the trachea to allow ventilation (Box 23-1). Locate the cricothyroid membrane by palpating the victim’s neck, beginning at the top. The first and largest prominence felt is the thyroid cartilage (“Adam’s apple”); the second prominence (below the thyroid cartilage) is the cricoid cartilage. The small space between these two, noted by a depression, is the cricothyroid membrane (Figure 23-30). With the victim lying on his or her back, cleanse the neck around the cricothyroid membrane with an antiseptic if one is readily available. Put on protective gloves. Make a vertical 2.5-cm (1-inch) incision with a knife through the skin over the membrane (go a little bit above and below the membrane) while using the fingers of your other hand to pry the skin edges apart. Anticipate bleeding from the wound. After the skin is incised and spread, puncture the exposed membrane by stabbing it with a knife or other sharp, penetrating object (Figure 23-31, A). Stabilize the larynx between the fingers of one hand and insert the improvised cricothyrotomy tube through the membrane with the other hand (Figure 23-31, B). Secure the object in place with tape.

BOX 23-1 Improvised Cricothyrotomy Tubes

Intravenous (IV) administration set drip chamber: Cut the plastic drip chamber of a macro drip (15 drops/mL) IV administration set at its halfway point with a knife or scissors. Remove the end protector from the piercing spike and insert the spike through the cricothyroid membrane. The plastic drip chamber is nearly the same size as a 15-mm endotracheal tube adapter and fits snugly in the valve fitting of a bag-valve device (Figure 23-32).

Syringe barrel: Cut the barrel of a 2- or 3-mL syringe with the plunger removed at a 45-degree angle at its midpoint to create an improvised cricothyroid airway device. The proximal flange of the syringe barrel helps secure the device to the neck and prevents it from being aspirated (Figure 23-33).

Any small hollow object: Examples include a small flashlight or penlight casing, some pen casings, or small hollow tube. The key question is whether sufficient air can pass through the tube for effective ventilation.

FIGURE 23-32 Improvised cricothyrotomy tube. A, Cut the plastic drip chamber at its halfway point. B, Insert the spike from the drip chamber through the cricothyroid membrane. C, A bag-valve device will fit over the chamber for ventilation.

FIGURE 23-33 An improvised cricothyroid airway device can be created by cutting the barrel of a syringe at a 45-degree angle at its midway point.

FIGURE 23-30 The cricothyroid membrane is found in the depression between the Adam’s apple (thyroid cartilage) and the cricoid cartilage.

FIGURE 23-31 Cricothyrotomy. A, Locate the cricothyroid membrane and make a vertical 1-inch incision through the skin. B, Insert the pointed end of an improvised cricothyrotomy tube through the membrane.

Complications associated with this procedure include hemorrhage at the insertion site, subcutaneous or mediastinal emphysema resulting from faulty placement of the tube into the subcutaneous tissues rather than into the trachea, and perforation through the posterior wall of the trachea with placement of the tube into the esophagus.

Improvised Wound Management

The same principles that govern wound management in the emergency department apply in the wilderness setting. The main problem faced in the wilderness is access to adequate supplies. In deciding whether to close a wound or pack it open, take into account the mechanism of injury, degree of contamination, patient’s age, site of the wound, and ability to effectively clean the wound.

Wound Irrigation

The primary determinants of infection are bacterial counts and amount of devitalized tissue remaining in the wound.²¹ Ridding a wound of bacteria and other particulate matter requires more than soaking and gentle washing with a disinfectant.⁴⁴ Irrigating the wound with a forceful stream is the most effective method of reducing bacterial counts and removing debris and contaminants.⁶⁸ The cleansing capacity of the stream depends on the hydraulic pressure under which the fluid is delivered.²⁰ Irrigation is best accomplished by attaching an 18- or 19-gauge catheter to a 35-mL syringe, or a 22-gauge needle to a 12-mL syringe. This creates hydraulic pressure in the range of 0.49 to 0.56 kg/cm² and 0.91 kg/cm² (7 to 8 psi and 13 psi), respectively.⁶³ The solution is directed into the wound from a distance of 1 to 2 inches (2.5 to 5 cm) at an angle perpendicular to the wound surface. The amount of irrigation fluid varies with the size and contamination of the wound but should average no less than 250 mL.²⁰ Remember: “The solution to pollution is dilution.”