Enteral nutrition by a Forward Surgical Team in Afghanistan.

Objectives: The modern practice of trauma surgery is a global physiologic approach to caring for the injured patient. Included in that approach is consideration of the traumatized patient's nutritional needs and implementing early enteral feeding. This is routine practice in the United States but logistically impractical when using commercial enteral feeding formulas in the austere environment of a Forward Operating Base in Afghanistan.

Methods: At a Forward Operating Base in southern Afghanistan, injured patients who were not expected to be taking a regular diet by 72 hours after injury are started on early enteral feedings. This is through nasogastric, gastrostomy, or jejunostomy tube, using formulas of pureed food available in the theater from local sources and supplemented with ingredients from US Army Meals-Ready-to-Eat. Preparation, nutritional calculation, and delivery are discussed.

Results: The injured soliders and Afghan nationals tolerated early enteral feedings with no complications encountered related to the feeding portal, infusion, or ingredients.

Conclusions: Early enteral feeding of traumatized patients in the far forward environment of southeastern Afghanistan is practical with the use of ingredients found locally in-theater.

Key Words: enteral feeding, forward surgical team, injury, military facility

**********

Increased military activity since 9/11 has resulted in the overseas deployment of numerous surgeons (both active duty and civilian reserve) to medical treatment facilities assembled in combat zones. Since the last major mobilization, for Desert Storm, the US Army's battlefield tactics and medical treatment strategies have evolved. Surgical treatment and critical care, once available only at large fixed US Army hospitals, now is pushed forward to the edge of the battlefield to augmented Forward Surgical Teams (FSTs). At the FST facility, the injured receive urgent surgical and/or orthopaedic care to preserve life, limb, or eyesight. Traditionally, the wounded soldier is treated by the FST only to control bleeding and contamination of his wounds, then is immediately evacuated to a higher-echelon facility en route to the continental United States.

In more recent conflicts, the surgical support structure in the theater has been upgraded to provide definitive care farther forward. With expansion in surgical capability comes a need for expanded postsurgical support, one component of which is enteral feeding. Since ancient Egypt, physicians have devised and refined ways of feeding patients who cannot or will not eat. (1) From the advent of nasogastric feeds in the 1600s to the rise of total parenteral nutrition in the late 1960s, the challenge to the physician caring for malnourished or nutritionally challenged patients is to provide adequate protein, calories, micronutrients, and water, while minimizing any side effects of the feeding or complications in its delivery system (eg, diarrhea, aspiration, central line infection). (2,3) It is the challenge of the military surgeon to accomplish early enteral feeding while awaiting patient evacuation from a combat zone.

Difficulties with patient evacuation in these forward areas have many causes. Poor weather near high mountains greatly affects rotary-wing (helicopter) assets. Heightened enemy activity in the FST area can preclude safe patient transport and divert armed escort assets to combat missions at the discretion of the commander. It is in this environment that FST surgeons, trained in modern critical care, are pressed to start enteral feedings to give the postsurgical patient the best chance of a successful outcome. Early enteral feeding correlates with improved outcomes when delivered as early as 2 hours after injury. (4)

Physician-directed enteral feeding of the hospitalized patient is a complex topic. The literature is full of various concoctions and replete with multiple theories about their efficacy. Eloquent papers have been published on the history of enteral feeds in the 1940s, the rise of safe parenteral feeds in the 1970s, and the commercially prepared enteral formulas that are exclusively used today. (5) These high-technology feeds are the result of a combination of medical needs (balanced components, vitamin supplementation, and so on) as well as commercial feasibility (mass production on an economically viable scale).

US military medical facilities are now present throughout the globe, and, due to the war on terrorism, increasingly located in underdeveloped countries. The local medical communities of countries such as Afghanistan resemble that of developed nations in the 1940s or earlier. It is logistically and economically impractical to produce and transport canned commercially prepared enteral feeding products in these nations where (1) the number of enteral feeds is relatively small, (2) the ability to store the product is limited, (3) transporting the product is dangerous or is of a lower priority than items like water and munitions, and (4) the projection of need for an amount of product is challenging. These challenges led us to pursue preparation and administration of enteral tube feeds at far-forward US military medical facilities and in local national hospitals, using modern nutritional knowledge in a practical manner, and foods available in the theater.

Techniques

In the past, enteral feeds have been successfully administered to patients through every anatomic segment of the gastrointestinal tract. (6) Some routes such as rectal nutrient enemas have been relegated to medical history, whereas other routes are currently used, depending on patient anatomy and injury pattern. The route of enteral feed administration used by the FST is through nasogastric tube, surgical gastrostomy tube, or surgical jejunostomy tube. Because of supply constraints as well as the single purpose use, the nasojejunal tube and route of administration is not used by the FST. The authors favor the use of the Stamm gastrostomy tube, whereby a 16F Foley catheter is placed at the time of laparotomy into the stomach along its greater curvature. If full oral alimentation is not anticipated within 72 hours, enteral feeding is considered.

In the initial postoperative 12 to 24 hours, the gastrostomy tube is placed to gravity drainage. Patients with the gastrostomy tube usually do not have a concomitant nasogastric tube in place. The lack of a nasogastric tube facilitates patient comfort, removes pressure on the nasal passages and maxillary sinus, and improves patient compliance with pulmonary toilet. Nasogastric tubes are used for enteral feeding in those trauma patients not requiring diagnostic or therapeutic laparotomy for injury (eg, land mine blast with traumatic amputations and/or mangled limbs). Enteral feeds are begun with low-fat (1%) milk through the feeding tube at 30 mL per hour. The FST is not equipped with pumps or other devices to provide continuous feedings; therefore, bolus feeds are the preferred method of administration. If continuous feedings are required (eg, jejunal feeds), our method is to empty a 100-mL intravenous bag of saline and fill it with low-fat milk. The gastrostomy tube (16F Foley catheter) is clamped upstream from the injection port and, by using an 18-gauge needle and standard intravenous tubing, the milk is infused into the feeding tube at a rate of 30 mL per hour. A Dial-a Flow (Abbott Laboratories, North Chicago, IL) is placed on the intravenous tubing to regulate the speed of milk infusion. Once patient tolerance for this trophic feed has been established, the rate of infusion is increased to 60 mL per hour, followed by additives to the milk feeding (US Army Meal-Ready-to Eat [MRE] dairyshake powder, Jianas Brothers Packaging Co, Kansas City, MO). Difficulties arise if the viscosity of the feeding increases to the point that the intravenous tubing or the feeding tube becomes clogged; therefore, the consistency of the feeds is checked by the nursing staff before instillation, and only small batches of prepared feeds are made so as not to permit time for precipitation of powdered contents from the milk before instillation. For evacuation by land or air to rearward medical facilities, the enteral feeds are stopped and the feed tube is placed to gravity drainage. Enteral feeding is resumed when the patient arrives at the US Combat Support Hospital with commercially prepared canned tube feeding products. If the patient remains with the FST and begins oral alimentation, the enteral tube feeds are reduced in proportion to the volume of oral feeds until full oral alimentation is achieved. Surgically placed feeding tubes are removed after 14 days if full oral feeding has been achieved or at any later time thereafter when full oral feeds occur. Seven injured soldiers and Afghan nationals were treated by the authors with early enteral feedings after major trauma. There were no complications related to the feeding portal, infusion, or ingredients.

Discussion

The need for nutrition in the trauma patient has been well documented. (5) In patients with intact alimentary tracts, enteral feeds are less expensive, more readily available, and are administered with less difficulty than parenteral feeds. The US military has the dubious but unavoidable distinction of placing its soldiers, airmen, and marines in harm's way, often in austere conditions. Nonetheless, these military trauma patients would seem to benefit from early enteral nutrition, as do their US civilian counterparts. Commercial parenteral nutrition is simply not available far forward on the battlefield. With transportation constraints, the US Army FST is not supplied with commercially available enteral feeding products. The injured soldier requires water, protein, calories, and micronutrients in either an isoosmolar form or at least a form compatible with digestion; it is the challenge of the FST surgeon to provide this nutrition despite his or her local constraints. The physician's choice of foodstuffs is limited by the available foods provided by the US Army for soldier's needs, or foods procured from the local economy. In Afghanistan, local food culture dictates that pork and its products (including products with animal-derived gelatin) are taboo, whereas economic and historical pressures make beef, citrus, potato, and onion products scarce. US Army food procurement officers spend countless hours purchasing foodstuffs for deployed soldiers that are palatable, comply with American social norms (eg, no breaded grasshoppers), and have a long storage life at extremes of temperature. It is within these constraints that the deployed surgeon must make enteral feeds de novo. Table 1 lists representative foods that could possibly be used for formulation into enteral tube feeds. Ultra-high-temperature pasteurized milk provides carbohydrates, fat, and protein in an acceptable ratio; its amino acid proportions are likewise favorable to the trauma patient. Its drawbacks are that ultra-high-temperature milk is not particularly caloriedense, nor does it contain the vitamin C, vitamin E, thiamin, or folate needed for proper wound healing and maintenance. A combination of the products listed in Table 1 or additional local foods (eg, mango, lentils, basmati rice, and so forth), prepared and pureed in a blender or hand-cranked food mill with sufficient water (for osmolarity and viscosity) would meet daily patient needs for protein, calories, fats, and micronutrients (Table 2). Local national physicians could undergo instruction on the preparation, administration, and nutritive value of pureed enteral feedings to a patient population that had previously known only weight loss, weakness, and starvation in the hospital.

Conclusion

The concept of surgical care far forward on the battle-field has saved US soldier's lives as well as provided the soldier with a sense of well-being in an otherwise terrifying situation ("If I get shot, there is a hospital close by that will save me"). Improvements to care delivered by the FST will only better the US fighting man and woman, and act as a model to nearby local hospitals that look at US medical care as a solution for their problems. One improvement is the early institution of enteral nutrition through gastrostomy or jejunostomy tube (nasal or surgical), using milk or pureed foods that are readily accessible. Although it is unlikely that such "field-expedient" enteral nutrition would match the quality of nutrition in commercial tube feed formulas, we believe it would nonetheless maintain small-bowel villi integrity, promote immune system function, and permit easier adaptation to full enteral nutrition products, once the injured soldier moves rearward to larger, better-equipped medical facilities. The addition of a blender, hand-cranked food mill, or food processor to the US Army FST would suffice to meet the nutritional requirements of the injured soldier, airman, or marine without undue cost to the Government. Lessons learned in the 1950s in hospital kitchens about the nutritive value of pureed enteral feeds remain true even today in far forward elements of the US Army Medical Department. (4) These lessons (and food blenders), exported to local national physicians in war-torn countries, may save lives of trauma patients, restore the strength of the population, and build goodwill and cooperation between countries such as Afghanistan and the United States.

I don't want to achieve immortality through my work; I want to achieve
immortality through not dying.
--Woody Allen

Table 1. Nutritional comparison of potential enteral feeding products,
Southeastern Afghanistan (a)

                                                   Milk, cow, 1%
                                                   fat with dairy
                                                   shake, (244 g
                              Milk, cow,  Milk,    milk + 100 g
Nutrient item or              1% fat      goat,    powder); 245 g
component                     244 g       245 g    serving

Calories                         102        168      436
Calories from                     46.6       42.5    205.4
  carbohydrate
Calories from fat                 20.8       88.8    142.2
Calories from protein             35.1       37.1     88.4
Total carbohydrate, g             12.2       10.9     52
Dietary fiber, g                   0          0        0
Starch, g                          0          0        3.6
Total sugars, g                   12.7       10.9     48.9
Glucose, mg                        0          (a)      (a)
Fructose, g                        0          (a)      (a)
Lactose, g                    12,690          (a)      (a)
Maltose, g                         0          (a)      (a)
Galactose, g                       0          (a)      (a)
Total fat, g                       2.4       10.1     15.9
Saturated fat, g                   1.5        6.5      3.6
Monounsaturated fat, g             0.7        2.7      (a)
Polyunsaturated fat, g             0.1        0.4      (a)
Total protein, g                   8.2        8.7     20.3
Tryptophan, mg                    97.6      107        (a)
Threonine, mg                    217        398        (a)
Isoleucine, mg                   456        505        (a)
Leucine, mg                      915        766        (a)
Lysine, mg                       700        708        (a)
Methionine, mg                   203        195        (a)
Cystine, mg                      283        112        (a)
Phenylalanine, mg                407        378        (a)
Tyrosine, mg                     346        437        (a)
Valine, mg                       529        586        (a)
Arginine, mg                     234        290        (a)
Histidine, mg                    205        217        (a)
Alanine, mg                      259        288        (a)
Aspartic acid, mg                759        512        (a)
Glutamic acid, mg              1,908      1,528        (a)
Glycine, mg                      154        122        (a)
Proline, mg                      876        898        (a)
Serine, mg                       508        442        (a)
Hydroxyproline, mg                 (a)        (a)      (a)
Vitamin A, IU                    478        483      478
Retinol, [micro]g                142        137      142
Alpha carotene, [micro]g           0          0        0
Beta carotene, [micro]g            4.9       17.1      4.9
Beta cryptoxanthin, [micro]g       0          0        0
Lycopene, [micro]g                 0          0        0
Vitamin C, [micro]g                0          3.2      3.9
Vitamin D, IU                    127         29.3    272
Vitamin E, [micro]g                0          0.2      0
Thiamin, mg                        0          0.1      0
Riboflavin, mg                     0.5        0.3      0.5
Niacin, mg                         0.2        0.7      0.2
Vitamin [B.sub.6], mg              0.1        0.1      0.1
Folate, [micro]g                  12.2        2.4     12.2
Food folate, [micro]g             12.2        2.4     12.2
Folic acid, [micro]g               0          0        0
Vitamin [B.sub.12], [micro]g       1.1        0.2      1.1
Pantothenic acid, mg               0.9        0.8      0.9
Vitamin K, [micro]g                0.2        0.7      0.2
Calcium, mg                      263        327      713
Iron, mg                           0.9        0.1      1.3
Magnesium, mg                     26.8       34.2     26.8
Phosphorus, mg                   217        271      217
Potassium, mg                    290        498      290
Sodium, mg                       122        122      122
Zinc, mg                           2.1        0.7      2.1
Copper, mg                         0          0.1      0
Manganese, mg                      0.1        0        0.1
Selenium, [micro]g                 8.1        3.4      8.1
Cholesterol, mg                   12.2       26.8     12.2

                              Juice, apple,  Soup,
                              canned,        chicken
                              without        noodle,    Meat,
                              added          canned,    goat,
Nutrient item or              vitamin C,     prepared,  roasted,
component                     248 g          241 g      245 g

Calories                         117            74.7      350
Calories from                    114            36.2        0
  carbohydrate
Calories from fat                  2.3          21.9       66.9
Calories from protein              0.5          16.6      283.1
Total carbohydrate, g             29             9.3        0
Dietary fiber, g                   0.2           0.7        0
Starch, g                          (a)           (a)        0
Total sugars, g                   27             0.3        0
Glucose, mg                    6,200             (a)        0
Fructose, g                   13,890             (a)        0
Lactose, g                         (a)           (a)        0
Maltose, g                         (a)           (a)        0
Galactose, g                       (a)           (a)        0
Total fat, g                       0.3           2.5        7.4
Saturated fat, g                   0             0.7        2.3
Monounsaturated fat, g             0             1.1        3.3
Polyunsaturated fat, g             0.1           0.6        0.6
Total protein, g                   0.1           4         66.3
Tryptophan, mg                     (a)          38.6      986
Threonine, mg                      (a)         128      3,157
Isoleucine, mg                     (a)         159      3,356
Leucine, mg                        (a)         265      5,527
Lysine, mg                         (a)         219      4,935
Methionine, mg                     (a)          77.1    1,777
Cystine, mg                        (a)          45.8      791
Phenylalanine, mg                  (a)         164      2,303
Tyrosine, mg                       (a)         106      2,039
Valine, mg                         (a)         176      3,555
Arginine, mg                       (a)         166      4,869
Histidine, mg                      (a)          94      1,383
Alanine, mg                        (a)         188          (a)
Aspartic acid, mg                  (a)         296          (a)
Glutamic acid, mg                  (a)       1,118          (a)
Glycine, mg                        (a)         190          (a)
Proline, mg                        (a)         263          (a)
Serine, mg                         (a)         145          (a)
Hydroxyproline, mg                 (a)           (a)        (a)
Vitamin A, IU                      2.5         696          0
Retinol, [micro]g                  0             2.4        0
Alpha carotene, [micro]g           0             0          0
Beta carotene, [micro]g            0           412          0
Beta cryptoxanthin, [micro]g       0             0          0
Lycopene, [micro]g                 0             0          0
Vitamin C, [micro]g                2.2           0.2        0
Vitamin D, IU                      (a)           (a)        (a)
Vitamin E, [micro]g                0             0.1        0.9
Thiamin, mg                        0.1           0.1        0.2
Riboflavin, mg                     0             0.1        1.5
Niacin, mg                         0.2           1.4        9.6
Vitamin [B.sub.6], mg              0.1           0          0
Folate, [micro]g                   0            21.7       12.2
Food folate, [micro]g              0             2.4       12.2
Folic acid, [micro]g               0            19.3          0
Vitamin [B.sub.12], [micro]g       0             0.1        2.9
Pantothenic acid, mg               0.2           0.2        (a)
Vitamin K, [micro]g                0             0          3
Calcium, mg                       17.4          16.9       41.6
Iron, mg                           0.9           0.8        9.1
Magnesium, mg                      7.4           4.8        0
Phosphorus, mg                    17.4          36.1      492
Potassium, mg                    295            55.4      991
Sodium, mg                         7.4       1,106        210
Zinc, mg                           0.1           0.4       12.9
Copper, mg                         0.1           0.2        0.7
Manganese, mg                      0.3           0.3        0.1
Selenium, [micro]g                 0.2           6.3       28.9
Cholesterol, mg                    0             7.2      184

                              Goldline one-     Daily
                              tablet-daily      requirements,
                              multiple vitamin  based on a
Nutrient item or              supplement, 1     2,000-calorie
component                     tablet            diet

Calories                          0             2,000
Calories from                     0             1,290
  carbohydrate
Calories from fat                 0               540
Calories from protein             0               170
Total carbohydrate, g             0               322
Dietary fiber, g                  0                25
Starch, g                         0                 (a)
Total sugars, g                   0                 (a)
Glucose, mg                       0                 (a)
Fructose, g                       0                 (a)
Lactose, g                        0                 (a)
Maltose, g                        0                 (a)
Galactose, g                      0                 (a)
Total fat, g                      0                60
Saturated fat, g                  0                 (a)
Monounsaturated fat, g            0                 (a)
Polyunsaturated fat, g            0                 (a)
Total protein, g                  0                50
Tryptophan, mg                    0                 (a)
Threonine, mg                     0                 (a)
Isoleucine, mg                    0                 (a)
Leucine, mg                       0                 (a)
Lysine, mg                        0                 (a)
Methionine, mg                    0                 (a)
Cystine, mg                       0                 (a)
Phenylalanine, mg                 0                 (a)
Tyrosine, mg                      0                 (a)
Valine, mg                        0                 (a)
Arginine, mg                      0                 (a)
Histidine, mg                     0                 (a)
Alanine, mg                       0                 (a)
Aspartic acid, mg                 0                 (a)
Glutamic acid, mg                 0                 (a)
Glycine, mg                       0                 (a)
Proline, mg                       0                 (a)
Serine, mg                        0                 (a)
Hydroxyproline, mg                0                 (a)
Vitamin A, IU                 5,000             4,970
Retinol, [micro]g                 (a)               (a)
Alpha carotene, [micro]g          (a)               (a)
Beta carotene, [micro]g           (a)               (a)
Beta cryptoxanthin, [micro]g      (a)               (a)
Lycopene, [micro]g                (a)               (a)
Vitamin C, [micro]g              60                55
Vitamin D, IU                   400               400
Vitamin E, [micro]g              30                30
Thiamin, mg                       1.5               1.5
Riboflavin, mg                    1.7               1.7
Niacin, mg                       20                20
Vitamin [B.sub.6], mg             2                 2
Folate, [micro]g                400               400
Food folate, [micro]g             (a)               (a)
Folic acid, [micro]g              (a)               (a)
Vitamin [B.sub.12], [micro]g      6                 6
Pantothenic acid, mg             10                10
Vitamin K, [micro]g               0                 (a)
Calcium, mg                       0             1,010
Iron, mg                          0                18
Magnesium, mg                     0               380
Phosphorus, mg                    0               986
Potassium, mg                     0             3,625
Sodium, mg                        0             2,440
Zinc, mg                          0                15
Copper, mg                        0                 2
Manganese, mg                     0                 (a)
Selenium, [micro]g                0                 (a)
Cholesterol, mg                   0               360

(a) Data unavailable for the parameter.
Nutritional comparison of food products available to the Forward
Surgical Team, Southeastern Afghanistan.
Reference: Nutrition Data, http://www.nutritiondata.com, August 1, 2004.
Goldline one-tablet-daily multiple vitamin by Goldline Laboratories,
Inc, Miami, FL.

Table 2. Suggested dietary plan (a)

                       Enteral feed,
                       24-hour period:
                       goat milk, 245       Percentage
                       mg; cow milk, 1%     of daily      Daily
                       with dairy shake,    requirements  requirements,
                       735 g; apple juice,  achieved      based on a
Nutrient item or       992 mg; one          by enteral    2,000-calorie
component              multivitamin         feeding       diet

Total carbohydrate, g   1,115                  86             1,290
Total fat, g              523                  97               540
Total protein, g          340                 200               170
Vitamin A, IU           6,927                 140             4,970
Vitamin C, [micro]g       837               1,522                55
Vitamin D, IU           1,245                 311               400
Vitamin E, [micro]g        30                 100                30
Thiamin, mg                 2                 133                 1.5
Riboflavin, mg              3.5               210                 1.7
Niacin, mg                 31.1               156                20
Vitamin [B.sub.6]           2.8               140                 2
Folate, [micro]g          439                 110               400
Vitamin [B.sub.12],         9.5               158                 6
  [micro]g
Pantothenic acid, mg       14.3               143                10
Calcium, mg             2,536                 251             1,010
Iron, mg                    7.6                42                18
Magnesium, mg             144.2                38               380
Phosphorus, mg            991.6               101               986
Potassium, mg           2,548                  70             3,625
Sodium, mg                517.6                21             2,440
Zinc, mg                    7.4                49                15
Copper, mg                  0.5                25                 2
Manganese, mg               1.5                 (a)               (a)
Selenium, [micro]g         28.5                 (a)               (a)
Cholesterol, mg            63.4                18               360

(a) Data unavailable for the parameter.

Accepted October 20, 2004.

References

1. Randall HT. The history of enteral nutrition, in Rombeau JL, Caldwell MD (eds): Enteral and Parenteral Nutrition. Philadelphia, PA: WB Saunders, 1984, p 110.

2. Pareira MD. Therapeutic Nutrition With Tube Feeding. Springfield, IL, Charles C. Thomas, 1959.

3. Dudrick S, Wilmore DW, Vars HM, et al. Long-term total parenteral nutrition with growth, development and positive nitrogen balance. Surgery 1968;64:134-142.

4. Mochizuki H, Trocki O, Dominioni L, et al. Mechanism of prevention of postburn hypermetabolism and catabolism by early enteral feeding. Ann Surg 1984;200:297.

5. Harkness L. The history of enteral nutrition therapy: from raw eggs and nasal tubes to purified amino acids and early postoperative jejunal delivery. J Am Diet Assoc 2002;102:399-404.

6. Jacobs DG, Jacobs DO, Kudsk KA, et al. Practice Management Guidelines for Nutritional Support of the Trauma Patient: the EAST Practice Management Guidelines Workgroup, Eastern Association for the Surgery of Trauma. 2003, pp 19-24. Available at www.ease.org/tpg.html. Accessed February 7, 2005.

RELATED ARTICLE: Key Points

* Feeding access can be safely placed in a Forward Surgical Team facility.

* Reasonable enteral nutrition formulas for US soldiers can be assembled from available foods on a Forward Operating Base.

* Properly selected local food can be formulated into an equivalent enteral feed for local nationals treated at US military facilities.

MAJ (P) James D. Frizzi, MC, USA, MAJ Peter D. Ray, MC, USAR, and CAPT John B. Raff, MC, USNR 

From the General Surgery Service, Dwight D. Eisenhower Army Medical Center, Fort Gordon, GA.

Reprint requests to Maj (P) James Frizzi, MC, General Surgery Service, Dwight D. Eisenhower Army Medical Center, Fort Gordon, GA 30905. Email: [e-mail]