Victor F. Garcia

Rib fractures in children: a marker of severe trauma

The early recognition of life-threatening injury is paramount to the prompt initiation of appropriate care. This study assesses the importance of multiple rib fractures as a marker of severe injury in children. We analyzed physiologic, etiologic, and injury data for 2,080 children with blunt or penetrating trauma aged 0-14 years consecutively admitted to a Level I pediatric trauma center. Analysis of variance, Students t-test, and the Chi-square test of independence were used to test for differences between children with rib fractures and other children. Probability of survival was modeled using stepwise logistic regression. There were 14 deaths among 33 children with rib fractures, a mortality rate of 42%. Child abuse accounted for 63% of the injuries to children less than 3 years old, while pedestrian injuries predominated among older children. Children with rib fractures were significantly more severely injured than children with blunt or penetrating trauma but without rib fractures. When compared to children without rib fractures, children with rib fractures had a higher mortality rate, but no statistically significant difference in morbidity. The mortality rate for the 18 children with both rib fractures and head injury was 71%. A logistic model with variables measuring severity of head injury and number of ribs fractured correctly predicted survival in more than 85% of children with thoracic trauma. Although rib fractures are rare injuries in childhood, they are associated with a high risk of death. The risk of mortality increases with the number of ribs fractured. The combination of rib fractures and head injury was usually fatal.

Reversal of Type 2 Diabetes Mellitus and Improvements in Cardiovascular Risk Factors After Surgical Weight Loss in Adolescents

OBJECTIVES. Type 2 diabetes mellitus is associated with obesity, dyslipidemia, and hypertension, all well-known risk factors for cardiovascular disease. Surgical weight loss has resulted in a marked reduction of these risk factors in adults. We hypothesized that gastric bypass would improve parameters of metabolic dysfunction and cardiovascular risk in adolescents with type 2 diabetes mellitus. PATIENTS AND METHODS. Eleven adolescents who underwent Roux-en-Y gastric bypass at 5 centers were included. Anthropometric, hemodynamic, and biochemical measures and surgical complications were analyzed. Similar measures from 67 adolescents with type 2 diabetes mellitus who were treated medically for 1 year were also analyzed. RESULTS. Adolescents who underwent Roux-en-Y gastric bypass were extremely obese (mean BMI of 50 ± 5.9 kg/m2) with numerous cardiovascular risk factors. After surgery there was evidence of remission of type 2 diabetes mellitus in all but 1 patient. Significant improvements in BMI (−34%), fasting blood glucose (−41%), fasting insulin concentrations (−81%), hemoglobin A1c levels (7.3%–5.6%), and insulin sensitivity were also seen. There were significant improvements in serum lipid levels and blood pressure. In comparison, adolescents with type 2 diabetes mellitus who were followed during 1 year of medical treatment demonstrated stable body weight (baseline BMI: 35 ± 7.3 kg/m2; 1-year BMI: 34.9 ± 7.2 kg/m2) and no significant change in blood pressure or in diabetic medication use. Medically managed patients had significantly improved hemoglobin A1c levels over 1 year (baseline: 7.85% ± 2.3%; 1 year: 7.1% ± 2%). CONCLUSIONS. Extremely obese diabetic adolescents experience significant weight loss and remission of type 2 diabetes mellitus after Roux-en-Y gastric bypass. Improvements in insulin resistance, β-cell function, and cardiovascular risk factors support Roux-en-Y gastric bypass as an intervention that improves the health of these adolescents. Although the long-term efficacy of Roux-en-Y gastric bypass is not known, these findings suggest that Roux-en-Y gastric bypass is an effective option for the treatment of extremely obese adolescents with type 2 diabetes mellitus.

Patterns of injury in children

Trauma is the leading cause of death for children over 1 year of age. This study was undertaken to identify the patterns of injury among children admitted to a regional pediatric trauma center. During a 34-month period, 3,472 injured children were consecutively admitted to a regional pediatric trauma center. Data were collected on medical, etiological, and financial aspects of injury. Eight subgroups were defined by mechanism of injury: motor-vehicle crash occupants, pedestrian and cycle injuries, falls, child abuse, gunshot and stab wounds, burns, poisonings, and foreign body ingestions or aspirations. Analysis of variance, Duncans multiple range test, and contingency table analysis were used to determine differences among subgroups of children. Blunt and penetrating trauma accounted for 64.3% of all admissions. The mean age of injured children was 5.5 years; 64% of the children were boys. Sixty-seven percent of the children were admitted directly from the scene of injury. One-way analysis of variance yielded significant differences in mean age, mean hospital length of stay (LOS), mean intensive care LOS, mean trauma score, mean injury severity, and mean hospital charges by mechanism of injury (P less than .01). The overall mortality rate was 2.4%. Child abuse, gunshot/stab wounds, and drowning had the highest mortality rates, but injuries to motor-vehicle crash occupants and pedestrians accounted for the greatest number of deaths.

Nitric oxide: An overview

Nitric oxide (NO), a paracrine-acting gas enzymatically synthesized from L-arginine, is a unique biologic mediator that has been implicated in a myriad of physiologic and pathophysiologic states. It is an important regulator of vascular tone and may be the mediator of the hemodynamic changes involved in sepsis and cirrhosis. In addition, there is increasing evidence that NO is involved in coagulation, immune function, inhibitory innervation of the gastrointestinal tract, protection of gastrointestinal mucosa, and the hepatotoxicity of cirrhosis. It has already been speculated that NO may represent a point of control or intervention in a number of disease states. The purpose of this paper is to provide the surgeon with a broad overview of the scientific and clinical aspects of this important molecule.

Reversibility of Cardiac Abnormalities in Morbidly Obese Adolescents

OBJECTIVES The purpose of this study was to evaluate changes in cardiac geometry, systolic and diastolic function before and after weight loss in morbidly obese adolescents. BACKGROUND Cardiac abnormalities are present in morbidly obese adolescents; however, it is unclear if they are reversible with weight loss. METHODS Data from 38 adolescents (13 to 19 years; 29 females, 9 males, 33 Caucasians, 5 African Americans) were evaluated before and after bariatric surgery. Left ventricular mass (LVM), left ventricular (LV) geometry, systolic and diastolic function were assessed by echocardiography. Mean follow up was 10 +/- 3 months. RESULTS Weight and body mass index decreased post-operatively (mean weight loss 59 +/- 15 kg, pre-operative body mass index 60 +/- 9 kg/m(2) vs. follow-up 40 +/- 8 kg/m(2), p < 0.0001). Change in LVM index (54 +/- 13 g/m(2.7) to 42 +/- 10 g/m(2.7), p < 0.0001) correlated with weight loss (r = 0.41, p = 0.01). Prevalence of concentric left ventricular hypertrophy (LVH) improved from 28% at pre-operative to only 3% at follow up (p = 0.007), and normal LV geometry improved from 36% to 79% at follow up (p = 0.009). Diastolic function also improved (mitral E/Ea lateral 7.7 +/- 2.3 at pre-operative vs. 6.3 +/- 1.6 at post-operative, p = 0.003). In addition, rate-pressure product improved suggesting decreased cardiac workload (p < 0.001). CONCLUSIONS Elevated LVM index, concentric LVH, altered diastolic function, and cardiac workload significantly improve following surgically induced weight loss in morbidly obese adolescents. Large weight loss due to bariatric surgery improves predictors of future cardiovascular morbidity in these young people.

Multidisciplinary pediatric trauma team training using high-fidelity trauma simulation.

BACKGROUND Trauma resuscitations require a high level of team performance. This study evaluated the impact of a comprehensive effort to improve trauma care through multidisciplinary education and the use of simulation training to reinforce training and evaluate performance. METHODS For a 1-year period, expanded trauma education including monthly trauma simulation sessions using high-fidelity simulators was implemented. All members of the multidisciplinary trauma resuscitation team participated in education, including simulations. Each simulation session included 2 trauma scenarios that were videotaped for debriefing as well as subsequent analysis of team performance. Scored simulations were divided into early (initial 4 months) and late (final 4 months) for comparison. RESULTS For the first year of the program, 160 members of our multidisciplinary team participated in the simulation. In the early group, the mean percentage of appropriately completed tasks was 65%, whereas in the late group, this increased to 75% (P < .05). Improvements were also observed in initial assessment, airway management, management of pelvic fractures, and cervical spine care. CONCLUSIONS Training of a multidisciplinary team in the care of pediatric trauma patients can be enhanced and evaluated through the use of high-fidelity simulation. Improvements in team performance using innovative technology can translate into more efficient care with fewer errors.

Pancreatic trauma in children: mechanisms of injury

BACKGROUND Pancreatic trauma occurs in up to 10% of all cases of blunt pediatric trauma. Here we attempted to identify markers of pancreatic injury in children and to assess our current diagnostic approach to pancreatic injury. METHOD We performed a retrospective chart review of all patients with a pancreatic injury admitted to a Level I pediatric trauma center between January of 1980 and September of 1994. RESULTS In all, 26 children were included. All pancreatic injuries were due to blunt trauma. Handlebar injuries were the most common mechanism of injury and resulted in a unique pattern of isolated pancreatic trauma, often complicated by the development of a pseudocyst. Computed tomographic scans, performed with intravenous and oral contrast and done in the acute setting, were 85% sensitive for diagnosing a pancreatic injury. CONCLUSIONS Double contrast computed tomographic scan is a more sensitive test than ultrasound in diagnosing pancreatic injury. The constellation of abdominal pain, an elevated serum amylase and a handlebar mechanism of injury warrants hospitalization and a double contrast abdominal computed tomographic scan.

Practice management guidelines for the management of mild traumatic brain injury: the EAST practice management guidelines work group.

I. STATEMENT OF THE PROBLEM Mild traumatic brain injury (MTBI), or concussion, is a common cause for admission at trauma centers, particularly those centers admitting primarily blunt trauma victims. Represented by ICD-9-CM codes 850.0–850.9, MTBI may be generally defined as an injury caused by blunt acceleration/ deceleration forces which produce a period of unconsciousness for 20 minutes or less and/or brief retrograde amnesia, a Glasgow Coma Scale (GCS) score of 13 to 15, no focal neurologic deficit, no intracranial complications (e.g., seizure activity), and normal computed tomography (CT) findings.1–3 This brief loss of consciousness and/or retrograde amnesia has to be referred to as a transient disturbance of neurologic function and is a sine qua non to the diagnosis of MTBI. Focal neurologic deficits as well as seizure activity fall outside the definition of MTBI in this guideline. Despite the frequency of MTBI, there is no uniform agreement regarding the nature of the illness, the role of a variety of diagnostic tests, or the necessity of acute hospitalization. Neurotrauma textbooks and a large number of review articles have addressed the definition, epidemiology, and clinical characteristics of MTBI.1–8 Similarly, a number of studies have examined the role of CT9–31 and neuropsychological testing32–46 in the diagnosis and management of MTBI. Several studies, mostly retrospective, suggest which patients might be best served by hospital admission versus evaluation and discharge to home.9,47–53 Additional studies exist regarding management strategies in MTBI from the neurosurgeon’s perspective.17,28,31,54–64 Finally, the complicated and poorly understood issues surrounding posttraumatic and emotional symptoms in patients with MTBI are discussed in several publications.65–69 From this core of knowledge, recommendations can be made to facilitate a safe, more uniform, and cost-effective approach to the understanding and management of MTBI.9,15,70–72

Selective inhibition of the inducible isoform of nitric oxide synthase prevents pulmonary transvascular flux during acute endotoxemia

The inducible isoform of nitric oxide synthase (iNOS) is expressed in various organs, including the lung, during systemic endotoxemia. Overproduction of nitric oxide (NO) by iNOS contributes significantly to the vascular failure and end-organ damage in endotoxemia. Using selective pharmacological inhibitors of iNOS, the purpose of this study was to define the role of iNOS in a rat model of endotoxin-induced pulmonary transvascular flux (TVF). Lung TVF was assessed by a method of Evans Blue permeability index (PI). Bacterial lipopolysaccharide (LPS) (15 mg/kg intraperitoneally [IP]) significantly increased pulmonary iNOS activity and serum levels of nitrite/nitrate (NO2/NO3). This was accompanied by a significant elevation of the PI 5 hours after injection. Selective iNOS inhibition with either S-methyl isothiourea (SMT; 5 mg/kg IP) or aminoguanidine (AG; 20 mg/kg IP), administered 2 hours after LPS injection, significantly prevented the increase in PI associated with LPS injection. Similarly, inhibition of the induction of iNOS with dexamethasone (10 mg/kg IP), given 3 hours before LPS, also inhibited the increase in PI. All three treatments significantly prevented the increase in both lung iNOS activity and serum NO2/NO3 associated with endotoxemia. In conclusion, the overproduction of NO generated by iNOS during systemic endotoxemia causes a vascular leak in the lung. Thus, it is speculated that selective inhibition of iNOS may be beneficial in preventing the development of acute respiratory failure in sepsis.

Histologic Spectrum of Nonalcoholic Fatty Liver Disease in Morbidly Obese Adolescents

BACKGROUND & AIMS To characterize the spectrum of nonalcoholic fatty liver disease (NAFLD) in morbidly obese adolescents, we correlated liver histology with clinical features and compared findings with reported adult data. We hypothesized that NAFLD would be less severe as a result of younger age and shorter duration of obesity, but portal inflammation and fibrosis would be more prevalent. METHODS Cross-sectional study was made of 41 adolescent subjects, 13-19 years old (mean, 16 years), 61% female, 83% non-Hispanic white, mean body mass index 59 kg/m(2), undergoing gastric bypass with liver biopsy. Liver biopsies were graded and staged as proposed by the NASH Clinical Research Network. Data were analyzed by using descriptive statistics, analysis of variance, and Fisher exact tests. RESULTS Eighty-three percent had NAFLD: 24% steatosis alone, 7% isolated fibrosis with steatosis, 32% nonspecific inflammation and steatosis, and 20% nonalcoholic steatohepatitis (NASH). Twenty-nine percent had fibrosis; none had cirrhosis. Abnormal ALT (P = .05) and AST (P = .01) were more prevalent in NASH. Mean fasting glucose was significantly higher in NASH (P = .05), but prevalence of the metabolic syndrome was not significantly different. CONCLUSIONS NAFLD was very prevalent in morbidly obese adolescents, but severe NASH was uncommon. In contrast to morbidly obese adults, lobular inflammation, significant ballooning, and perisinusoidal fibrosis were rare, whereas portal inflammation and portal fibrosis were more prevalent, even in those who did not meet criteria for NASH. These findings might support use of a modified scoring system for pediatric NASH. Presence of the metabolic syndrome in morbidly obese adolescents did not distinguish NASH from steatosis alone.