The Bowel: Contamination, Colostomies, and Combat Surgery

Abstract

Traumatic bowel injury in the combat casualty is extremely common and the surgeon must be comfortable with its management. Luckily, despite all that is written, the basic principles that govern the operative management for traumatic bowel injury boil down to the control of hemorrhage and contamination, assessment of bowel viability, determination of the need to resect vs. repair, and choice of reconstruction. Combat casualties tend to present with a multitude of injuries from combined mechanisms, so they must often be managed through means not typical of civilian trauma surgery. This is not the setting or the patient population to “try out” some great new technique you just read about or to push the envelope of primary reconstruction. While there are many ways to “skin a cat,” we will present some techniques and advice that we found useful in the management of these complex injuries.

Civilian Translation of Military Experience and Lessons Learned

• Scott R. Steele 

Key Similarities

• Following the standard principles of maintaining adequate blood supply, avoiding tension, apposing healthy bowel segments, and performing a technically appropriate operation are keys to excellent outcomes when performing a bowel anastomosis.

• The decision to repair versus doing damage control may be similar to what the remote rural surgeon faces.

Key Differences

• Access to diagnostic equipment such as radiology and endoscopy may not be available in the combat environment and lead to higher rates of exploration.

• High-velocity injuries of the colon and rectum may be better treated with diversion.

• Resource allocation and remote location associated with the military setting pose additional challenges that may require a change in management plan (i.e., damage control surgery implementation or having a low threshold for abdominal exploration with even the seemingly innocuous penetrating abdominal wounds).

Discussion

Many of the lessons learned in combat have direct relevance to the civilian sector and are easily applied in both environments. Specifically, regarding bowel injuries, the majority of patients in both settings can still be safely managed in primary fashion using direct repair or bowel resection and anastomosis. Regardless of the situation, traditional principles of a safe and proper repair/anastomosis must still be adhered. More extensive injuries in either setting do not necessarily mandate proximal diversion. However, patients with significant and sustained hypotension, large transfusion requirements, concomitant major comorbidities or associated injuries, and uncontrolled abdominal sepsis may benefit from diversion, as outcomes are generally inferior regardless of the method of repair. Alternatively, definitive reconstruction or diversion can be delayed in the setting of the severely injured patient at significant risk of hypothermia, coagulopathy, and acidosis – the lethal triad – by invoking the principles of damage control surgery . Prevention of further fecal contamination and hemorrhage control through the use of clamps, staplers, umbilical tape, or even a “whip stitch” can rapidly accomplish the immediate goals in these severely injured patients and allow for resuscitation and delayed management of the bowel injury when the patient is more stable.

Nevertheless, variations in care based on the combat versus civilian sector appropriately exist. Military trauma is often associated with high-velocity wounds, multiple associated injuries to adjacent or distant organs from fragments, and significant burns that may result in wide-ranging physiological variations. These fluid requirements may lead to significant bowel edema that can impact healing in the setting of primary repair. In addition, the associated thermal damage to the bowel from high-velocity wounds may evolve over time, resulting in areas of delayed injury presentation that may result in a leak. Collateral damage to adjacent structures may result in a high morbidity that can have a direct impact on the bowel anastomosis.

The military surgeon must also consider the environmental differences that can dramatically impact the treatment plan. Initially, the lack of diagnostic equipment such as multi-slice CT scanners or endoscopy may cause the military surgeon to proceed with abdominal exploration at a much higher rate. Diagnostic laparoscopic equipment is almost routinely unavailable as well. Therefore, rates of negative exploration may be much higher in combat, where conservative “watch and wait” strategy is impossible due to the surrounding circumstances. Moreover, while a missed injury may result in detrimental outcomes in both settings, the resultant consequences in theater may be much more severe. Supply limitations and remote locations often play a role in the combat environment and pose additional challenges for which the military surgeon must be aware. Injured soldiers may be required to have prolonged transportation within and between theaters, resulting in segments of time where constant high-level attention may not be available or direct access to the operating room is not possible. In light of these differences, diversion may be a more sound or attractive option, even when primary anastomosis is possible. Furthermore, the combat environment is littered with instances of multiple casualties and limited surgical personnel. The military environment, similar to a mass casualty in a remote rural environment , must not only take into consideration the patient’s anatomy, physiology, and injury pattern but also the number and degree of other incoming casualties, blood and other product availabilities, as well as holding capacity and evacuation needs for all injured personnel.

In an effective civilian trauma setting , the higher levels of care should have good communication and awareness of the capabilities of the smaller surrounding hospitals. Stabilization of intestinal injuries may be the only thing possible for the smaller community hospital. Subsequently, planned second looks and transferring of patients with open abdomens should be expected, particularly if there are multiple other traumatic injuries. Subsequently, open and collegial feedback of such cases should be considered and implemented to help improve the system for future events.

Final Points

Just as any infantryman goes into battle with an assortment of weapons, ammunition, and techniques, you must go into the operating room armed for the various scenarios you may encounter. Don’t make the mistake of treating combat casualties like you would with victims of civilian trauma. The anastomosis that looks great when constructed will be leaking in 48–72 h, and you will scratch your head and wonder why. They are just sicker patients. The mechanisms of injury are more severe and are often combined in additive or exponential fashion. It is not uncommon to see a patient that has a combination of blunt, blast, burn, and penetrating trauma. They will not react or heal like someone who was wounded with a 9 mm pistol or was in a car accident. There will be times when you can revert to the standard methods, but when confronted with a very injured and very unstable casualty, you have to assume and prepare yourself for the worst.