Early surgical intervention and its impact on patients presenting with necrotizing soft tissue infections: A single academic center experience

OBJECTIVES

Early diagnosis and emergent surgical debridement of necrotizing soft tissue infections (NSTIs) remains the cornerstone of care. We aimed to study the effect of early surgery on patients' outcomes and, in particular, on hospital length of stay (LOS) and Intensive Care Unit (ICU) LOS.

MATERIALS AND METHODS

Over a 6-year period (January 2003 through December 2008), we analyzed the records of patients with NSTIs. We divided patients into two groups based on the time of surgery (i.e., the interval from being diagnosed and surgical intervention): Early (<6 h) and late (≥6 h) intervention groups. For these two groups, we compared baseline demographic characteristics, symptoms, and outcomes. For our statistical analysis, we used the Student's t-test and Pearson Chi-square (χ(2)) test. To evaluate the clinical predictors of early diagnosis of NSTIs, we performed multivariate logistic regression analysis.

RESULTS

In the study population (n = 87; 62% males and 38% females), age, gender, wound locations, and comorbidities were comparable in the two groups. Except for higher proportion of crepitus, the clinical presentations showed no significant differences between the two groups. There were significantly shorter hospital LOS and ICU LOS in the early than late intervention group. The overall mortality rate in our study patients with NSTIs was 12.5%, but early intervention group had a mortality of 7.5%, but this did not reach statistical significance.

CONCLUSIONS

Our findings show that early surgery, within the first 6 h after being diagnosed, improves in-hospital outcomes in patients with NSTIs.

Enterocutaneous fistulas and a hostile abdomen: reoperative surgical approaches

Damage-control surgery and open-abdomen is an acceptable—and often lifesaving—approach to the treatment of patients with severe trauma, abdominal compartment syndrome, necrotizing soft tissue catastrophes, and other abdominal disasters, when closing the abdomen is not possible, ill advised, or will have serious sequelae. However, common consequences of open-abdomen management include large abdominal wall defects, enterocutaneous fistulas (ECFs), and enteroatmospheric fistulas (EAFs). Furthermore, in such patients, a frozen and hostile abdomen (alone or combined with ECFs) is not uncommon. Adding biologic mesh to our surgical armamentarium has revolutionized hernia surgery.

Defining incidence and outcome of contrast-induced nephropathy among trauma: is it overhyped?

Contrast-induced nephropathy (CIN) in trauma patients is uncommon and the incidence is unknown. We studied the incidence of CIN and its outcome. A retrospective chart review of trauma patients 16 years of age and older who were admitted to our Level I trauma center during 2005 was performed. Patients who received the intravenous contrast CT scan and had their serum creatinine (Cr) monitored at admission and at 48 to 72 hours were identified. CIN was defined as a 0.5-mg/dL rise of serum Cr or a 25 per cent increase from the baseline if the baseline Cr was abnormal. We excluded patients transferred from an outside facility, patients without repeated serum Cr measurements, patients who had cardiac arrest or persistent hypotension, and patients who had received N-acetylcysteine (Mucomyst) before their CT scan. We compared CIN and non-CIN groups. During 2005, 543 fit our study criteria, of whom 19 (3.5%) had CIN. CIN (vs non-CIN) had a higher baseline serum Cr (1.48 + 0.23 vs 1.06 + 0.02, P < 0.001), a longer intensive care unit stay (17 vs 5 days, P < 0.001), and a longer hospital stay (19 vs 8 days, P < 0.001); the mortality rate was not different (10 vs 4%, P = 0.2). We found elevated baseline serum Cr (OR, 1.92; 95% CI, 1.13 to 3.27; P = 0.016) to be associated with increased risk for CIN. All but two serum Cr levels peaked within 48 hours; all returned to baseline. One patient with an underlying congenital kidney disease required temporary dialysis. CIN incidence in trauma is low and the clinical course is benign.

Defining Incidence and Outcome of Contrast-Induced Nephropathy Among Trauma: Is It Overhyped?

Contrast-induced nephropathy (CIN) in trauma patients is uncommon and the incidence is unknown. We studied the incidence of CIN and its outcome. A retrospective chart review of trauma patients 16 years of age and older who were admitted to our Level I trauma center during 2005 was performed. Patients who received the intravenous contrast CT scan and had their serum creatinine (Cr) monitored at admission and at 48 to 72 hours were identified. CIN was defined as a 0.5-mg/dL rise of serum Cr or a 25 per cent increase from the baseline if the baseline Cr was abnormal. We excluded patients transferred from an outside facility, patients without repeated serum Cr measurements, patients who had cardiac arrest or persistent hypotension, and patients who had received N-acetylcysteine (Mucomyst) before their CT scan. We compared CIN and non-CIN groups. During 2005, 543 fit our study criteria, of whom 19 (3.5%) had CIN. CIN (vs non-CIN) had a higher baseline serum Cr (1.48 + 0.23 vs 1.06 + 0.02, P < 0.001), a longer intensive care unit stay (17 vs 5 days, P < 0.001), and a longer hospital stay (19 vs 8 days, P < 0.001); the mortality rate was not different (10 vs 4%, P = 0.2). We found elevated baseline serum Cr (OR, 1.92; 95% CI, 1.13 to 3.27; P = 0.016) to be associated with increased risk for CIN. All but two serum Cr levels peaked within 48 hours; all returned to baseline. One patient with an underlying congenital kidney disease required temporary dialysis. CIN incidence in trauma is low and the clinical course is benign.

Seatbelt Triad: Severe Abdominal Wall Disruption, Hollow Viscus Injury, and Major Vascular Injury

The triad of seatbelt-related severe abdominal wall disruption, hollow viscus injury, and distal abdominal aortic injury after a motor vehicle collision is uncommon. We present a small case series involving those three clinical features with the goal of preventing a future missed diagnosis of the distal abdominal aortic injury in particular.

Energy Substrate-Supplemented Resuscitation Affects Brain Monocarboxylate Transporter Levels and Gliosis in a Rat Model of Hemorrhagic Shock

BACKGROUND

Monocarboxylate (MC)-supplemented resuscitation has been shown to attenuate cellular injury after hemorrhagic shock. However, little is known about its effect on the central nervous system. The brain can use MCs such as lactate, pyruvate, and beta-hydroxybutyrate as energy substrates. The transit of MCs into the central nervous system is facilitated by the monocarboxylate transporters (MCTs), and their blockage can exacerbate neuronal damage. We examined the expression of MCT1 and markers specific for activation of astroglia and microglia in the brains of rats subjected to hemorrhagic shock and resuscitation. The hypothesis was that resuscitation with MC-based fluids would be accompanied by MCT1 up-regulation and glial response.

METHODS

Rats (n = 30) were subjected to volume-controlled hemorrhage. Test groups included: sham, no resuscitation, resuscitation with normal saline, resuscitation with racemic lactated Ringer's solution, resuscitation with pyruvate Ringer's solution, and resuscitation with beta-hydroxybutyrate-containing ketone Ringer's solution. Plasma levels of MC were measured serially. The brains were investigated using GFAP, CD11b, CD43, MCT1, and GLUT1 immunohistochemistry.

RESULTS

Rats resuscitated with MC-containing fluids had increased levels of MCT1 in brain endothelial cells and neuropil compared with sham rats. Enhanced staining was localized to the choroid plexus, astrocytic end feet, and white matter structures. None of the resuscitation treatment induced astrocytic hyperplasia, and pyruvate Ringer's solution and ketone Ringer's solution resuscitation led to hypertrophy of astrocytes.

CONCLUSION

In hemorrhagic shock, resuscitation with MC-based fluids increased brain MCT1 level and led to activation of astrocytes. Enhanced MC trafficking could be an essential route for energy supply to neurons under adverse circulatory conditions.

Lumbar fractures in adult blunt trauma: axial and single-slice helical abdominal and pelvic computed tomographic scans versus portable plain films

BACKGROUND

Our hypothesis was that abdominal and pelvic computed tomographic (AP-CT) scans are equivalent to portable two-view plain films in detecting lumbar spine fractures in adults. Since many trauma patients often undergo AP-CT scanning to evaluate for possible intra-abdominal injuries, using the AP-CT scan to screen for lumbar fractures could make the trauma evaluation process more efficient.

METHODS

The institutional trauma registry at a Level I trauma center was used to identify all blunt lumbar fractures during a 6-year period. Medical records were reviewed.

RESULTS

A total of 7,216 adult blunt trauma patients were evaluated, and 115 patients were identified as having a lumbar fracture, for an incidence rate of 1.6%. Missed fracture rates were high for both AP-CT scans (23.2%, 13 of 56) and portable two-view films (12.7%, 14 of 110, = 0.08). Fifty-two patients had both AP-CT scans and plain films. In this group, AP-CT scans missed 23.1% (12 of 52) of the lumbar fractures and plain films missed 15.4% (8 of 52). However, the combination of the two diagnostic methods did not miss any fractures (0 of 52). The missed fractures required surgery or brace in 50% (7 of 14) patients who had fractures missed by plain films and 46% (6 of 13) patients whose fractures were missed by AP-CT scanning.

CONCLUSION

Both AP-CT scans and plain films failed to diagnose significant lumbar fractures that required therapy. When screening for lumbar fractures, obtaining both AP-CT scans and portable two-view plain films may decrease missed lumbar fractures in blunt adult trauma.

Cytokine expression profiling in human leukocytes after exposure to hypertonic and isotonic fluids

BACKGROUND

Resuscitation from hemorrhagic shock causes profound immunologic changes. The tonicity of fluids used for resuscitation clearly influences the immune response. Our study was designed to determine whether isotonic and hypertonic fluids exert their differential effects on immune response by altering the cytokine gene profile of human leukocytes. The cDNA array method was used to profile transcriptional responses after exposure to hypertonic and isotonic fluids.

METHODS

Blood from seven healthy volunteers was incubated for 30 minutes with isotonic (10% dextran-40 and lactated Ringer's [LR] solution) and hypertonic (7.5% hypertonic saline and hypertonic dextran [HTD]) fluids. The volumes of isotonic fluids used were equal to the volume of blood, whereas the volumes of hypertonic fluids were adjusted to keep the salt load identical to the LR group. The cDNA array technique was used to measure the gene expression of 23 common cytokines.

RESULTS

Increased gene transcription of proinflammatory cytokines (interleukin [IL]-1alpha, IL-6, IL-10, and tumor necrosis factor-alpha) as well as others (IL-5, IL-7, and IL-16) was found after incubation with resuscitation fluids. Variances were noted depending on the type of fluid: HTD and LR solution did not induce expression of IL-5, and HTD also did not induce IL-1beta expression. Genes encoding IL-1alpha, IL-6, IL-9, and tumor necrosis factor-alpha had low level baseline expression in leukocytes isolated from unstimulated blood, and their expression increased markedly after exposure to resuscitation fluids. The inducible transcripts included IL-1beta, IL-7, IL-10, and IL-16. However, there was no difference in cytokine expression profile between isotonic and hypertonic fluids.

CONCLUSION

Exposure of human leukocytes to resuscitation fluids causes an increase in cytokine gene expressions compared with undiluted blood. This expression profile is largely independent of the type of fluid used.

Effects of lactated Ringer's solutions on human leukocytes

BACKGROUND

The standard lactated Ringer's (LR) solution contains racemic lactate, an equal mixture of D(-)- and L(+)-isomers. The aim of this study was to investigate whether racemic LR solution (containing both isomers, dl-LR) differs from LR containing L-isomer only (L-LR).

METHODS

Blood from 20 volunteers was incubated for 30 minutes with lactated Ringer's solutions containing the DL- or L-form of lactate, Hank's balanced salt solution, normal saline, and ketone Ringer's (lactate replaced with ketone bodies). Neutrophil "oxidative burst" was measured using flow cytometry. Gene expression of 23 genes associated with leukocyte function was determined with cDNA array technique. The arraying procedure was repeated four times to obtain four sets of data.

RESULTS

Compared with the L-LR and ketone Ringer's, DL-LR causes an increased production of reactive oxygen species by neutrophils and affects expression of leukocyte genes known to be involved in inflammation, cell migration, and apoptosis.

CONCLUSION

Lactated Ringer's solution in commonly used formulation (racemic mixture, DL-LR) influences neutrophil function and leukocyte gene expression.

Survival after emergency department thoracotomy: review of published data from the past 25 years

BACKGROUND

Emergency department thoracotomy (EDT) has become standard therapy for patients who acutely arrest after injury. Patient selection is vitally important to achieve optimal outcomes without wasting valuable resources. The aim of this study was to determine the main factors that most influence survival after EDT.

STUDY DESIGN

Twenty-four studies that included 4,620 cases from institutions that reported EDT for both blunt and penetrating trauma during the past 25 years were reviewed. The primary outcomes analyzed were in-hospital survival rates.

RESULTS

EDT had an overall survival rate of 7.4%. Normal neurologic outcomes were noted in 92.4% of surviving patients. Factors reported as influencing outcomes were the mechanism of injury (MOI), location of major injury (LOMI), and signs of life (SOL). Survival rates for MOI were 8.8% for penetrating injuries and 1.4% for blunt injuries. When penetrating injuries were further separated, the survival rates were 16.8% for stab wounds and 4.3% for gunshot wounds. For the LOMI, survival rates were 10.7% for thoracic injuries, 4.5% for abdominal injuries, and 0.7% for multiple injuries. If the LOMI was the heart, the survival rate was the highest at 19.4%. The third factor influencing outcomes was SOL. If SOL were present on arrival at the hospital, survival rate was 11.5% in contrast to 2.6% if none were present. SOL present during transport resulted in a survival rate of 8.9%. Absence of SOL in the field yielded a survival rate of 1.2%. There was no clear single independent preoperative factor that could uniformly predict death.

CONCLUSIONS

The best survival results are seen in patients who undergo EDT for thoracic stab injuries and who arrive with SOL in the emergency department. All three factors-MOI, LOMI, and SOL-should be taken into account when deciding whether to perform EDT. Uniform reporting guidelines are needed to further elucidate the role of EDT taking into account the combination of MOI, LOMI, and SOL.

Penetrating cardiac injuries: a population-based study

BACKGROUND

Wide variances exist in reports of survival rates after penetrating cardiac injuries because most are hospital-based reports and thus are affected by the local trauma system. The objective of this study was to report population-based, as well as hospital-based, survival rates after penetrating cardiac injury.

METHODS

Retrospective cohort analysis was performed during a 7-year period of 20,181 consecutive trauma admissions to a regional Level I trauma center and 6,492 medical examiner's reports. A meta-analysis was performed comparing survival rates with available population-based reports.

RESULTS

There were 212 penetrating cardiac injuries identified, for an incidence of approximately 1 per 100,000 man years and 1 per 210 admissions. The overall survival rate was 19.3% (41 of 212) for the population studied, with survival rates of 9.7% (12 of 123) for gunshot wounds and 32.6% (29 of 89) for stab wounds. Ninety-six of the 212 patients were transported to the trauma center for treatment, resulting in an overall hospital survival rate of 42.7% (41 of 96), with a hospital survival rate of 29.3% (12 of 41) for gunshot wounds and 52.7% (29 of 55) for stab wounds.

CONCLUSION

Review of population-based studies indicates that there has been only a minor improvement in the survival rates for the treatment of penetrating cardiac injuries.

Unique aspects of anticipated shipboard vascular trauma

This article mentions notable historical examples of vascular injuries that occur at sea. It traces the development of modern ships and the concomitant capability to provide medical care to the personnel who go in harm's way on these ships. The importance of vascular surgery training for the general surgeon assigned to sea duty is stressed.

The effect of payer status on utilization of hospital resources in trauma care

OBJECTIVE

To determine the effect of payer status on outcome and resource utilization in motor vehicle-related trauma patients.

DESIGN

Retrospective cohort analysis that assessed the effect of payer status on outcome and resource utilization.

SETTING

The single level I trauma center in a regionalized statewide system.

PATIENTS

Consecutive patients (N = 3141) who were hospitalized after a motor vehicle crash during a 3-year period.

MAIN OUTCOME MEASURES

The mortality rate, disposition, total hospital length of stay (LOS), total intensive care unit LOS, and total hospital charges were examined for 2 categories of payers: "commercial insurance" (commercial, labor and industry, and contract pay) and "noncommercial insurance" (Medicaid and self-pay).

RESULTS

After controlling for age, sex, race, and the Injury Severity Score, the payer status had no overall effect on the mortality rate, disposition, total hospital charges, total hospital LOS, or total intensive care unit LOS. However, there was a significantly (11.4%; P < .05) longer LOS for those patients with noncommercial insurance who required transfer to another facility for rehabilitation or long-term care.

CONCLUSIONS

The utilization of hospital trauma care resources in a level I facility in a regionalized system was not associated with insurance status. Patients with noncommercial insurance who required transfer to elective long-term care facilities had a longer LOS due to delays in obtaining subsequent access. Health care policy should provide appropriate reimbursement for all aspects of regionalized trauma care systems to ensure maintenance of an egalitarian approach to care.