Thomas A. Mitchell

An 8-Year Review of Operation Enduring Freedom and Operation Iraqi Freedom Resuscitative Thoracotomies

BACKGROUND Appropriate indications for resuscitative thoracotomy (RT) in an austere environment continue to evolve; the aim of this study was to determine survival and to analyze demographics of survivors within U.S. military personnel undergoing RT. METHODS A retrospective review was performed of all U.S. soldiers who underwent thoracotomy in theater during Operation Iraqi Freedom and Operation Enduring Freedom. After individualized review, patients in extremis or who lost pulses and had their thoracotomy performed within 10 minutes of arrival to the emergency department were included. The primary outcome was survival at final hospital discharge, and secondary outcomes included demographics associated with survival. RESULTS Between January 2003 and May 2010, 81 U.S. military personnel met inclusion criteria for RT in theater. As low as 6.7% (3/45) of patients receiving prehospital cardiopulmonary resuscitation were alive at final hospital discharge. Survival from RT after explosive/blast injury, penetrating (gunshot wound), and blunt trauma were 16.3% (8/49), 0% (0/28), and 0% (0/4), respectively. Patients with primary explosive/blast extremity trauma undergoing RT had a survival of 27.3% (6/22). Higher initial oxygen saturations, larger volume of crystalloids and blood products infused, and higher extremity abbreviated injury score were all associated with survival. CONCLUSIONS Combat casualties who present pulseless or in extremis who were injured as a result of an explosive/blast injury mechanism resulting in a primary extremity injury may have a survival benefit from undergoing a RT in an austere environment.

Mucormycosis Attributed Mortality: A Seven-year Review of Surgical and Medical Management

INTRODUCTION Historically, mucormycosis infections have been associated with high mortality. The purpose of this study was to determine the incidence, associated mortality, and management strategies of mucormycosis in a major burn center. METHODS A retrospective review was performed via obtaining all patients with mucormycosis admitted from January 2003 to November 2009 at our adult burn center was performed obtaining demographic data relevant to fungal burn wound infection or colonization. RESULTS The incidence of mucormycosis at our facility was 4.9 per 1000 admissions; specifically, 11 military casualties and one civilian were diagnosed with mucormycosis. The median percentage Total Body Surface Area (TBSA) burned, 11 patients, or open wound, one patient, was 60 (IQR, 54.1-80.0), and the incidence of documented inhalation injury was 66.7% (8 of 12). Ten patients had surgical amputations. A median of eight days (IQR, 3.5-74.5) elapsed from diagnosis of mucormycosis until death in the 11 patients who expired. The overall mortality was 92%; however, autopsy attributed mucormycosis mortality was 54.5% (6 of 11) with all six patients having invasive mucormycosis. CONCLUSION Aggressive surgical intervention should be undertaken for invasive mucormycosis; additionally, implementation of standardized protocols for patients with large soft tissue injuries may mitigate mucormycosis superimposition.

Control of severe intra-abdominal hemorrhage with an infusible platelet-derived hemostatic agent in a nonhuman primate (rhesus macaque) model.

BACKGROUND Hemorrhage remains the leading cause of potentially survivable trauma mortality. Recent reports indicate that injuries sustained in noncompressible anatomic locations (i.e., truncal and junctional) account for 86.5% of hemorrhage-related deaths. Infusible human platelet-derived hemostatic agents (hPDHAs) represent a promising strategy to reduce blood loss from noncompressible injuries. Here, we evaluate the hemostatic efficacy of a lyophilized hPDHA in a rhesus macaque model of severe, uncontrolled hemorrhage. METHODS Hemorrhage was induced via laparoscopic 60% left-lobe hepatectomy in anesthetized rhesus macaques (T = 0 minute). Treatment infusion began with an 11-mL bolus (T = 5–6 minutes) of either 5% albumin solution (control; n = 8) or hPDHA (1.2 × 1010 platelet equivalents, n = 8), followed by 2.8-mL/min 0.9% normal saline at T = 6–20 minutes. Resuscitation continued with normal saline (0.22 mL/kg/min) to a total volume of 20 mL/kg at T = 120 minutes, at which time surgical hemostasis was achieved and percent blood loss quantified. Animals were monitored until T = 480 minutes and then euthanized, and necropsy was performed with emphasis on intravascular and end-organ thrombi. Data are expressed as mean ± SEM; significance, p < 0.05. RESULTS Both groups exhibited a ∼70% decrease in mean arterial pressure (MAP) from T = 0–5 minutes. Percent blood loss was 44.2 ± 3.9% in hPDHA animals, and 44.3 ± 3.3% in controls. Survival rates were 4 of 8 for hPDHA animals and 7 of 8 for controls. Regardless of treatment, percent blood loss was greater (p < 0.02) in nonsurviving animals (55 ± 2%, n = 5) compared with surviving animals (42% ± 3%, n = 11). No pathologic intravascular thrombi were observed in either group. CONCLUSION The isolated administration of hPDHA did not significantly reduce blood loss; however, thrombocytopenia was not present in the model, and clinically, platelets would be administered in combination with plasma. Mortality was not statistically different between groups (p = 0.14) but was related to blood loss. Future studies should consider the use of hPDHA in combination with additional therapeutics (e.g., factors) and a model that incorporates thrombocytopenia or platelet dysfunction.

Nontherapeutic laparotomy in American combat casualties: A 10-year review

BACKGROUND The civilian literature has expanded the indications for selective nonoperative management (SNOM) for abdominal trauma to minimize morbidity from nontherapeutic laparotomies (NTLs); however, this treatment modality remains controversial and rare in austere settings. This study aimed to quantify the percentage of NTL and incidence of failed SNOM performed in theater and to define each of their respective intra-abdominal–related morbidities. METHODS A retrospective evaluation of all patients who underwent a laparotomy from 2002 to 2011 during Operation Iraqi Freedom (OIF) and Operation Enduring Freedom (OEF) was performed for patients who survived a minimum of 24 hours. With the use of DRG International Classification of Diseases—9th Rev. procedure codes, a therapeutic laparotomy was defined by the presence of a defined intraperitoneal or retroperitoneal procedure; an NTL was defined by the absence of a defined intraperitoneal or retroperitoneal procedure. Second, patients transferred from North American Treaty Organization Role II to Role III medical treatment facilities to be operated on were deemed failed SNOM. Finally, intra-abdominal complications and mortality were identified for patients undergoing therapeutic laparotomy, NTL, and failed SNOM. RESULTS Blunt, burn, and penetrating injuries accounted for 38.5% (n = 490), 1.1% (n = 14), and 60.4% (n = 769) of all laparotomies in the OEF and OIF, respectively. Thirty-two percent of all laparotomies performed during the OEF and OIF campaigns were NTL; specifically, the NTL rates in OEF and OIF were 38.2% and 28.6%, respectively. In addition, 31.6% and 32.2% of all penetrating and blunt injury mechanisms resulted in an NTL, respectively. The percentage of all patients identified as failing SNOM was 7.5% (n = 95). The early intra-abdominal complication rate for failed SNOM and for all patients undergoing NTL was 2.1% and 1.7%, respectively. CONCLUSION The OIF and OEF combined NTL rate was 32.1%, with an associated 1.7% intra-abdominal early complication rate. The infrequent application of SNOM in a deployed military environment is likely secondary to unpredictable fragmentation trajectories and related blast injury patterns, limited medical resources including computed tomography, and a complex aeromedical evacuation system preventing serial observation. LEVEL OF EVIDENCE Epidemiologic study, level IV.

Short-Term Outcomes and Complications of Damage Control and Definitive Laparotomy in Deployed Combat Environments: 2002 to 2011

INTRODUCTION Damage control laparotomy (DCL) in an austere environment is an evolving surgical modality. METHODS A retrospective evaluation of all patients surviving 24 hours who underwent a laparotomy from 2002 to 2011 in Iraq and Afghanistan was performed. DCL was defined as a patient undergoing laparotomy at two distinct North American Treaty Organization (NATO) Role 2 or 3 medical treatment facilities (MTFs); a NATO Roles 2 and 3 MTFs, and/or having the International Classification of Diseases, 9th Revision, Clinical Modification procedure code 54.12, for reopening of recent laparotomy site. Definitive laparotomy (DL) was defined as patients undergoing one operative procedure at one NATO Role 2 or 3 MTF. Demographic data including injury severity scores, hematological transfusion, mortality, intraperitoneal or retroperitoneal operative interventions, and complications were compared. RESULTS DCL composed of 26.5% (n = 331) of all 1,248 laparotomies performed between March 2002 and September 2011. Total intra-abdominal, acute respiratory distress syndrome, and thromboembolic complications for DCL versus DL were 8.5% and 5.6% (p = 0.07), 2.1% and 0.8% (p = 0.06), and 1.5% and 0.7% (p = 0.17), respectively. Theater discharge mortality from DCL and DL were 1.5% (n = 5), and 1.4% (n = 13) (p = 0.90), respectively. CONCLUSIONS In conclusion, excluding deaths with the first 24 hours, DCL and DL had comparable mortality and complication rates at NATO Roles 2 and 3 MTFs.

Interatrial Bronchogenic Cyst Resection

Interatrial bronchogenic cysts are rare entities, and the long-term clinical sequelae are unknown. This case report details the removal of a large (>4 cm) interatrial bronchogenic cyst that had been present for more than 10 years. Surgical resection remains the current standard of therapy when encountering an interatrial mass.

Evaluation of the Effectiveness of the 2008 Postsplenectomy Vaccination Joint Theater Trauma System Clinical Practice Guideline

OBJECTIVES Postsplenectomy vaccination (PSV) in an austere environment to minimize overwhelming postsplenectomy infection is challenging. We evaluated the clinical impact of a March 2008 clinical practice guideline (CPG) dictating immediate PSV at North American Treaty Organization Role 3 medical treatment facilities and subsequent complications. METHODS Utilizing U.S. military medical databases, we characterized all U.S. patients with a splenic injury from November 2002 to January 2012 by their surgical management: laparotomy with splenectomy (LWS), laparotomy without splenectomy, or nonoperative management. Relevant data including demographics, vaccinations, and documented bacterial and fungal isolates were obtained. RESULTS LWS comprised 63.6% of the 409 patients with a splenic injury from 2002 to 2012. The implementation of the PSV CPG improved overall vaccination compliance from 48.9% pre-PSV CPG to 86.9% post-PSV CPG (p < 0.01). It was found that 1.3% (2/159) of completely vaccinated LWS patients compared with 0% (0/101) of the incompletely vaccinated LWS patients had Streptococcus pneumoniae isolates in 391.0 and 251.4 follow-up years, respectively (p = 0.52). No Neisseria meningitidis or Haemophilus influenzae isolates were identified. CONCLUSIONS PSV CPG implementation improved theater vaccination without increasing the incidence of encapsulated organisms.

Principles for Damage Control in Military Casualties

Conceptually, damage control principles are rooted in military origins; the surgical application is analogous to US Navy terminology for “the capacity of a ship to absorb damage and maintain mission integrity” [16]. The interval termination of an operation has been described with liver packing as early as 1908; however, the practice was ended soon after high infectious rates were identified [8]. The introduction of a formal laparotomy by World War I improved mortality; however, the essence of damage control surgery was further captured in World War II, as exploratory laparotomy became the standard of care for penetrating abdominal trauma, and surgeons gained vast experience in comprehending the necessity for expedited abdominal exploration hemodynamically unstable patients [8]. Specifically, in the Western desert in 1942, Watts highlighted that a war surgeon “must evacuate the wounded with all possible speed, both to clear the unit and to restore its mobility…that he must wherever possible, avoid the procedures that will prevent the early evacuation of the patient” [8]. This resonated on the battlefield; however, it wasn’t until 1983 that Dr. Harlan Stone, a civilian, reinstituted rapid packing and termination of the laparotomy in civilian trauma patients when intraoperative coagulopathy became excessive [8]. Ten years later, Rotondo specifically termed the phrase “damage control surgery” where patients that underwent damage control surgery with two or more visceral injuries and/or had a major vascular injury had a markedly higher survival in a small nonrandomized cohort [77% (10 of 13) vs. 11% (1 of 9), p < 0.02]. Currently, more recent publications have demonstrated an improved 30-day survival [73.6% vs. 54.8%; p = 0.009] and a decreased mean trauma intensive care unit [11 v 20 days; p = 0.01] stay in patients receiving a massive transfusion that underwent damage control laparotomy and damage control resuscitation [9]. Although this methodology to appropriately care for severely injured civilian patients would appear to extrapolate well to an austere environment, the transition to military austere environments was initially questioned by many.

Nonoperative management of splenic injury in combat: 2002-2012.

BACKGROUND Selective nonoperative management of combat-related blunt splenic injury (BSI) is controversial. We evaluated the impact of the November 2008 blunt abdominal trauma clinical practice guideline that permitted selective nonoperative management of some patients with radiological suggestion of hemoperitoneum on implementation of nonoperative management (NOM) of splenic injury in austere environments. METHODS Retrospective evaluation of patients with splenic injuries from November 2002 through January 2012 in Iraq and Afghanistan was performed. International Classification of Diseases, 9th Revision, Clinical Modification procedure codes identified patients as laparotomy with splenectomy, or NOM. Delayed operative management had no operative intervention at earlier North American Treaty Organization (NATO) medical treatment facilities (MTFs), and had a definitive intervention at a latter NATO MTFs. Intra-abdominal complications and overall mortality were juxtaposed. RESULTS A total of 433 patients had splenic injuries from 2002 to 2012. Initial NOM of BSI from 2002 to 2008 compared to 2009-2012 was 44.1% and 47.2%, respectively (p=0.75). Delayed operative management and NOM completion had intra-abdominal complication and mortality rates of 38.1% and 9.1% (p<0.01), and 6.3% and 8.1% (p=0.77). CONCLUSIONS Despite high-energy explosive injuries, NATO Role II MTFs radiological constraints and limited medical resources, hemodynamically normal patients with BSI and low abdominal abbreviated injury scores underwent NOM in austere environments.