Sherene Shalhub

Effect of Immediate Enteral Feeding on Trauma Patients with an Open Abdomen: Protection from Nosocomial Infections

BACKGROUND Damage-control laparotomy has become increasingly common after operative resuscitation of severe hemorrhagic shock after injury. Despite increased use, uncertainty exists about the safety and timing of enteral nutrition. The purpose of this study was to determine the safety and effect of immediate enteral nutrition. STUDY DESIGN Data were obtained from a multicenter prospective cohort study evaluating clinical outcomes in adults with hemorrhagic shock after injury and were limited to patients with an open abdomen and no hollow viscus injury. The immediate enteral nutrition cohort was defined as initiation of enteral feeds within 36 hours after acute resuscitation completion. Multivariate stepwise logistic regression was used to evaluate factors associated with immediate enteral nutrition. RESULTS One hundred subjects met inclusion criteria; 32 immediate enteral nutrition and 68 nonimmediate enteral nutrition. Nearly all patients underwent fascial closure (93.8% immediate enteral nutrition versus 94.1% nonimmediate enteral nutrition), with an average closure day of 6.47 +/- 0.83 with immediate enteral nutrition and 8.55 +/- 0.85 with nonimmediate enteral nutrition (p = 0.129). No significant difference in multiorgan dyfunction syndrome, length of ventilator days, ICU days, hospital days, or mortality was seen between groups. The rate of pneumonia was significantly different: 14 (43.8%) in immediate enteral nutrition and 49 (72.1%) in nonimmediate enteral nutrition (p = 0.008). Immediate enteral nutrition remained independently associated with a reduction in pneumonia within our stepwise regression (odds ratio = 0.32; 95% CI, 0.13 to 0.79). CONCLUSIONS Immediate enteral nutrition after damage control appears safe, with no effect on abdominal closure rate. In addition, the reduction in pneumonia associated with immediate enteral nutrition suggests a tangible benefit. Immediate enteral nutrition should be considered in patients with open abdomens after severe trauma.

Complications of PTFE Mesh at the Diaphragmatic Hiatus

Paraesophageal hernia repair has been associated with a recurrence rate of up to 42%. Thus, in the last decade, there has been increasing interest in the use of mesh reinforcement of the hiatal repair. Polytetrafluoroethylene (PTFE) is one of the materials that have been used for this purpose, as it is thought to induce minimal tissue reaction. We report two cases in which complications specific to the use of PTFE mesh in this location developed over time. In the first patient, a gastrectomy was required to remove a large PTFE mesh which had eroded into the esophagogastric junction and gastric cardia. The second patient experienced severe dysphagia resulting from a stricture caused by the implant, requiring removal of the mesh. Although such complications have only rarely been reported, the severity and consequences of these incidents, as reported in the literature and in light of our observations, suggest that an alternative to PTFE should be considered for crural reinforcement during paraesophageal hernia repair.

The evaluation of pneumomediastinum in blunt trauma patients.

BACKGROUND Pneumomediastinum occurs in up to 10% of patients with blunt thoracic and cervical trauma. Mandatory evaluation of all patients with bronchoscopy and esophageal imaging to exclude a major injury has been recommended. There is little data on the safety or efficacy of this approach. We evaluated the incidence of major injuries associated with pneumomediastinum, the accuracy of diagnostic modalities, and the results of observation versus aggressive evaluation. METHODS Medical records of all blunt trauma patients diagnosed with pneumomediastinum and/or aerodigestive tract injury between 1998 and 2005 were reviewed. The patients hospital course was reviewed for demographic data, admission diagnoses, diagnostic imaging and procedures, operations, missed injuries, length of stay, and mortality. RESULTS The review identified a total of 136 patients with pneumomediastinum, and an additional 22 patients with thoracic aerodigestive tract injuries but without pneumomediastinum. Only patients with pneumomediastinum were considered in subsequent analysis. Pneumomediastinum was detected by CT scan in all 136 (100%) patients, although identified on plain radiograph in only 20 (15%) patients. Computed tomography findings were suspicious for a major aerodigestive tract injury in 27 (20%) patients. Ten (37%) of these 27 patients had an injury requiring operative intervention: five (4%) laryngeal injuries, three (2%) tracheal disruptions, and two (1%) esophageal perforations. Eighty-one patients (60%) never had endoscopic evaluation. There were no delayed diagnoses, missed injuries, or complications in the observation-only cohort. The overall sensitivity and specificity of CT scan for major aerodigestive tract injury was 100% and 85%, respectively. CONCLUSION Major airway or esophageal injury is an uncommon cause of pneumomediastinum. CT scan was able to identify patients at high risk for aerodigestive injury in all cases, and should be the preferred screening tool for airway injury in patients with pneumomediastinum.

Treatment and outcomes of aortic endograft infection

OBJECTIVE This study examined the medical and surgical management and outcomes of patients with aortic endograft infection after abdominal endovascular aortic repair (EVAR) or thoracic endovascular aortic repair (TEVAR). METHODS Patients diagnosed with infected aortic endografts after EVAR/TEVAR between January 1, 2004, and January 1, 2014, were reviewed using a standardized, multi-institutional database. Demographic, comorbidity, medical management, surgical, and outcomes data were included. RESULTS An aortic endograft infection was diagnosed in 206 patients (EVAR, n = 180; TEVAR, n = 26) at a mean 22 months after implant. Clinical findings at presentation included pain (66%), fever/chills (66%), and aortic fistula (27%). Ultimately, 197 patients underwent surgical management after a mean of 153 days. In situ aortic replacement was performed in 186 patients (90%) using cryopreserved allograft in 54, neoaortoiliac system in 21, prosthetic in 111 (83% soaked in antibiotic), and 11 patients underwent axillary-(bi)femoral bypass. Graft cultures were primarily polymicrobial (35%) and gram-positive (22%). Mean hospital length of stay was 23 days, with perioperative 30-day morbidity of 35% and mortality of 11%. Of the nine patients managed only medically, four of five TEVAR patients died after mean of 56 days and two of four EVAR patients died; both deaths were graft-related (mean follow-up, 4 months). Nineteen replacement grafts were explanted after a mean of 540 days and were most commonly associated with prosthetic graft material not soaked in antibiotic and extra-anatomic bypass. Mean follow-up was 21 months, with life-table survival of 70%, 65%, 61%, 56%, and 51% at 1, 2, 3, 4, and 5 years, respectively. CONCLUSIONS Aortic endograft infection can be eradicated by excision and in situ or extra-anatomic replacement but is often associated with early postoperative morbidity and mortality and occasionally with a need for late removal for reinfection. Prosthetic graft replacement after explanation is associated with higher reinfection and graft-related complications and decreased survival compared with autogenous reconstruction.

Blunt Abdominal Aortic Injury

BACKGROUND Blunt abdominal aortic injury (BAAI) is a rare injury with less than 200 cases in the current reported world literature, mostly in case report format. We sought to describe the experience of a high-volume trauma center and to provide a contemporary review of the literature to better understand the natural history and management of this injury. METHODS This was a retrospective review of patients with BAAI between 1996 and 2010. Data collected included demographics, mechanism of injury, associated injuries, type of intervention, subsequent imaging, and follow-up. BAAI was classified by the presence of external aortic contour abnormality noted as an intimal tear, large intimal flap, pseudoaneurysm, or free rupture. Abdominal aorta zones of injury were classified by possible surgical approaches as zone I (diaphragmatic hiatus to superior mesenteric artery [SMA]), zone II (includes SMA and renal arteries), and zone III (from the inferior aspect of the renal arteries to the aortic bifurcation). RESULTS We identified 28 individuals (68% male) with BAAI (median age, 28.5; range, 6-61 years). The median injury severity score was 45 (range, 16-75), and 39% were hypotensive at presentation. BAAI presented as intimal tear (21%), large intimal flap (39%), pseudoaneurysm (11%), and free rupture (29%). Zone III was the most common location of injury. Management depended on the location and type of injury: nonoperative (32%), open aortic repair (36%), endovascular repair (21%), and multimodality (10%). Overall mortality was 32%. Most deaths occurred during the initial operative exploration. The mortality rate of free aortic rupture was 100%. Intimal tears resolved or remained stable. Median follow-up was 15.5 months (range, 8 days-7.5 years). Vascular complications due to repair included a thrombosed access femoral artery during an endovascular repair and death of a patient who underwent a hybrid repair. CONCLUSIONS This is the largest BAAI series described in the English literature at one institution. BAAIs range from intimal tears to free rupture, with outcomes and management correlating with type and location of injury. Nonoperative management with blood pressure control using β-blockers coupled with antiplatelet therapy and close follow-up is successful in individuals with intimal tears with minimal thrombus formation because they remain stable or resolve on follow-up. Free rupture remains a devastating injury, with 100% mortality. For all other categories of aortic injury, successful repair correlates with a favorable prognosis.

Variation in the TLR4 gene influences the risk of organ failure and shock posttrauma: a cohort study.

BACKGROUND Genetic variation contributes to risk and outcomes of sepsis. We sought to determine whether variation in inflammation related genes is associated with severity of sepsis in trauma patients. METHODS A cohort of severely injured Caucasian patients was studied and genotyped for candidate single nucleotide polymorphisms (SNPs). These were toll-like receptor 4 (TLR4) A896G, tumor necrosis factor-alpha G-308A, interleukin-6 G-174C, interleukin-1beta C-31T, and cluster of differentiation marker 14C-159T. SNP genotypes among patients with sepsis and complicated sepsis were analyzed by chi2 and logistic regression. Six haplotype-tagging SNPs in the TLR4 gene were subsequently examined to analyze their influence on TLR4 A896G SNPs relationship to sepsis severity. RESULTS We enrolled 598 patients. Complicated sepsis developed in 147 (25%). Adjusting for independent risk factors, carriage of the variant TLR4 896 G allele was associated with decreased risk of complicated sepsis (odds ratio = 0.3, 95% confidence interval, 0.1-0.7, p = 0.008). Furthermore, two haplotypes seemed to better characterize this risk than the variant TLR4 896G allele. The variant TLR4 896G allele is linked to one common haplotype, which seems to confer a considerably reduced risk of complicated sepsis. (aOR = 0.2 95% confidence interval, 0.05-0.7, p = 0.01). CONCLUSIONS Variation within TLR4 gene is associated with severity of posttraumatic sepsis. This risk may not be solely related to TLR4 A896G SNP. It is likely that other, uncharacterized variations in the TLR4 gene contribute to sepsis severity. A thorough evaluation of variability within the TLR4 gene is needed to characterize sepsis risk.

The association between the transfusion of older blood and outcomes after trauma.

Allogeneic packed red blood cells (PRBCs) suppress immunity and influence outcomes. The influence of blood on the risk of infection and death may be related to the duration of storage. We sought to determine whether blood storage duration was associated with infection or death in a large cohort of injury victims. We reviewed a cohort of trauma patients transfused at least 1 U of PRBCs within 24 h of admission to a level 1 trauma center. The outcomes of interest were complicated sepsis and mortality. We compared the amount of older blood (>14 days storage) given to patients who did or did not develop the outcomes of interest using univariate and multivariate methods. A total of 820 patients were included. Patients who died (n = 117) received more units of older blood than those who lived (5 U [inter quartile range {IQR}, 2-9] vs. 3 U [IQR, 2-6]; P < 0.001). Patients with complicated sepsis (n = 244) received a greater volume of older blood than those without complicated sepsis (6 U [IQR, 2-10] vs. 3 U [IQR, 1-5]; P < 0.001). After adjusting for clinical factors, including the total amount of blood transfused, patients receiving greater than or equal to 7 U of older blood had a higher risk of complicated sepsis than patients receiving 1 or fewer units (odds ratio, 1.9; P = 0.03). The risk for complicated sepsis and death in trauma victims who are transfused blood is high. The amount of older blood transfused is associated with complicated sepsis. Although the best strategy to minimize the effects of allogeneic blood is to avoid unnecessary transfusions, it may be particularly important to avoid transfusing multiple units of older blood.

Repair of blunt thoracic outlet arterial injuries: an evolution from open to endovascular approach.

BACKGROUND Thoracic outlet artery injuries due to blunt trauma are uncommon. Exposure of these arteries is associated with significant morbidity and mortality. An endovascular approach is a less invasive alternative approach for these technically challenging injuries. METHODS A retrospective review of patients who presented with blunt traumatic injuries to the innominate, subclavian, and axillary arteries between 1998 and 2009 was performed. Demographic data, concomitant injuries, preoperative workup, treatment, and outcomes were recorded. RESULTS During the study period, 34 patients (80% men) meeting selection criteria were admitted (11 innominate, 16 subclavian, and 7 axillary). Management was nonoperative in 6, open in 16, and endovascular in 12 patients. In the latter group, eight patients had successful stent-graft insertions. These were approached in an antegrade femoral or retrograde brachial fashion. In three cases of complete artery transaction, both methods were used. Shorter operative time (149 minutes vs. 230 minutes; p = 0.03) and less blood loss (50 mL vs. 1,225 mL; p = 0.03) were seen in the endovascular group compared with the open repair group. There was a trend for less blood transfusion, but it was not significant (0 median units vs. 4.5 median units; p = 0.3). Hospital length of stay was shorter (19 days vs. 29 days; p = 0.4). CONCLUSIONS Covered stents are a feasible alternative to open repair in the multiply injured blunt trauma patients with thoracic outlet arterial injuries. This can be used in the damage control setting as it offers shorter operative time, less blood loss, and overall less morbidity to the patient. Long-term follow-up is needed.

Tumor necrosis factor gene variation and the risk of mortality after burn injury: a cohort study.

Infection risk and mortality after burn trauma are primarily determined by patient age, burn size and depth, and associated inhalation injury. Whether genetic differences contribute to otherwise unexpected variability in outcomes is unknown. We sought to determine whether there was an association between genetic variation in inflammation-related genes and outcomes after burn trauma. We evaluated patients with burns ≥15% TBSA at a single regional burn center from October 2003 to December 2005. Blood was collected on admission and DNA genotyping was performed. We genotyped single nucleotide polymorphism (SNPs) in toll-like receptor 4 (TLR4) A896G, tumor necrosis factor alpha (TNF-&agr;) G-308A, Interleukin-6 (IL-6) G-174C, interleukin-1&bgr; (IL-1&bgr;) T-31C, and cluster of differentiation marker 14 (CD14) C-159T. We compared SNP genotypes between survivors and nonsurvivors by &khgr;2 analysis and logistic regression. Sixty-nine subjects with a median age of 38 years and mean TBSA of 34% were enrolled. The case fatality was 17%. Septic shock developed in 7 (10%) patients. After adjustment for age, percent full-thickness burns, and inhalation injury, carriage of the TNF-&agr; −308 variant allele was associated with increased risk of mortality (OR 10.7, 95% CI = 1.2–95.5, P = .034). None of the other SNPs evaluated were associated with mortality. Mortality after burn trauma is primarily determined by clinical factors, but the TNF-&agr; −308 A allele seems to contribute to an increased mortality risk.

Endovascular treatment of axillosubclavian arterial transection in patients with blunt traumatic injury

Axillosubclavian arterial transection due to blunt traumatic injury poses a treatment challenge in the multiply injured patient. Endovascular repair can be technically successful if the injury is focal. We describe an endovascular technique utilizing combined brachial and femoral access to create a through-and-through brachial-femoral wire and repair the arterial injury with a covered stent.