The effect of obesity on outcomes in trauma patients: a meta-analysis

High volume crystalloid resuscitation adversely affects pediatric trauma patients

BACKGROUND

Aggressive fluid resuscitative strategies have been the cornerstone of early trauma management for decades. However, recent prospective adult studies have challenged this practice, underlining the detrimental effect of positive fluid balance on cardiopulmonary function. Fluid overload has been associated with impaired oxygenation and morbidity in critically ill adults, but data is lacking in pediatric trauma patients.

METHODS

We completed a retrospective chart review of all pediatric trauma patients 0-18 years old admitted to a level 1 trauma center from January 2013 to December 2015. Four patient cohorts were established based on volume of fluid administered: <20 ml/kg/day, 20-40 ml/kg/day, 40-60 ml/kg/day, and > 60 ml/kg/day. The primary outcome was death. Secondary outcomes included the number of days on the ventilator, intensive care unit length of stay (ICU LOS), overall length of stay (LOS), number of days nil per os (NPO) as an indicator of ileus, and incidence of bloodstream infection and/or surgical site infection.

RESULTS

The mean volume of fluid administered over the first 24 h was 41 ml/kg/day, and 28 ml/kg/day over the first 48 h. ICU length of stay and overall length of stay were increased in patients who received more than 60 ml/kg/day in the first 24 h of their hospitalization. Furthermore, ventilator use, ICU length of stay, overall length of stay, and time to resumption of a regular diet were all increased in patients who received >60 ml/kg/day over 48 h.

CONCLUSIONS

Early administration of high volumes of crystalloid fluid greater than 60 ml/kg/day significantly correlates with pulmonary complications, days NPO, and hospital length of stay. These results span the first 48 h of a patient's hospital stay and should encourage surgical care providers to exercise judicious use of crystalloid fluid administration in the trauma bay, ICU, and floor.

TYPE OF STUDY

Therapeutic.

LEVEL OF EVIDENCE

Level III.

Obesity in the Polytrauma Patient

The rates of obesity continue to increase in the United States and the overall impact of obesity on health care spending and patient outcomes after trauma is considerable. The unique physiology of the obese places them at higher risk for complications, including infection, failure of fixation, nonunion, multiorgan failure, and death. These physiologic differences and overall patient size can make orthopedic care in obese patients with trauma more difficult, but appropriate initial resuscitation, careful preoperative planning, meticulous surgical technique, diligent postoperative medical management, and specialized rehabilitation give these patients their best opportunity for a good outcome.

Metabolic support challenges with obesity during critical illness

Adiposity-based chronic disease, critical illness, and nutrition therapy increase the risk for overfeeding and worsened nutritional and clinical outcomes. Hypocaloric, high-protein nutrition therapy provides critically ill obese patients the opportunity to achieve net protein anabolism with a reduced risk for overfeeding-related complications. The intent of this review is to discuss the impact of obesity on clinical outcomes, describe the consequences of obesity that increase complications associated with nutrition therapy, provide the framework to develop a hypocaloric, high-protein regimen, review the scientific evidence to support this mode of therapy, and discuss its limitations. Practical suggestions for patient monitoring are also provided.

Guiding Management in Severe Trauma: Reviewing Factors Predicting Outcome in Vastly Injured Patients

Trauma is one of the leading causes of death worldwide, with road traffic collisions, suicides, and homicides accounting for the majority of injury-related deaths. Since trauma mainly affects young age groups, it is recognized as a serious social and economic threat, as annually, almost 16,000 posttrauma individuals are expected to lose their lives and many more to end up disabled. The purpose of this research is to summarize current knowledge on factors predicting outcome - specifically mortality risk - in severely injured patients. Development of this review was mainly based on the systematic search of PubMed medical library, Cochrane database, and advanced trauma life support Guiding Manuals. The research was based on publications between 1994 and 2016. Although hypovolemic, obstructive, cardiogenic, and septic shock can all be seen in multi-trauma patients, hemorrhage-induced shock is by far the most common cause of shock. In this review, we summarize current knowledge on factors predicting outcome - more specifically mortality risk - in severely injured patients. The main mortality-predicting factors in trauma patients are those associated with basic human physiology and tissue perfusion status, coagulation adequacy, and resuscitation requirements. On the contrary, advanced age and the presence of comorbidities predispose patients to a poor outcome because of the loss of physiological reserves. Trauma resuscitation teams considering mortality prediction factors can not only guide resuscitation but also identify patients with high mortality risk who were previously considered less severely injured.

Prevalence of cardiovascular and respiratory complications following trauma in patients with obesity

BACKGROUND

It is generally accepted that obesity puts patients at an increased risk for cardiovascular and respiratory complications after surgical procedures. However, in the setting of trauma, there have been mixed findings in regards to whether obesity increases the risk for additional complications.

OBJECTIVE

The aim of this study was to identify whether obese patients suffer an increased risk of cardiac and respiratory complications following traumatic injury.

METHODS

A retrospective analysis of 275,393 patients was conducted using the 2012 National Trauma Data Bank. Hierarchical regression modeling was performed to determine the probability of experiencing a cardiac or respiratory complication.

RESULTS

Patients with obesity were at a significantly higher risk of cardiac and respiratory complications compared to patients without obesity [OR: 1.81; CI: 1.72-1.91]. Prevalence of cardiovascular and respiratory complications for patients with obesity was 12.6% compared to 5.2% for non-obese patients.

CONCLUSIONS

Obesity is predictive of an increased risk for cardiovascular and respiratory complications following trauma.

Body Mass Index >35 as Independent Predictor of Mortality in Severe Traumatic Brain Injury

OBJECTIVE

Severe traumatic brain injury (TBI) has a major influence on polytrauma outcome. The aim of this study was to evaluate the impact of body mass index (BMI) on mortality and early neurologic outcome in patients suffering from severe TBI with a special focus on obesity classes II and III (BMI ≥35).

METHODS

A retrospective cohort analysis of patients suffering from a leading, at least severe TBI and registered in the TraumaRegister DGU was conducted. Patients alive on admission with full status documentation on Glasgow Coma Scale, height, and weight were classified into 4 BMI subgroups. Early neurologic outcome was classified using the Glasgow Outcome Scale.

RESULTS

A total of 1634 patients met the inclusion criteria. Lowest mortality was documented for BMI group 1 (15.2%, BMI 25.0-29.9918.5). Highest mortality was found in BMI group 5 (25.6%, BMI ≥35). BMI ≥35 was an independent predictor of mortality with an odds ratio of 3.15 (95% confidence interval [1.06-9.36], P = 0.039). Further independent mortality predictors were >65 years of age, a Glasgow Coma Scale of ≤13, an Abbreviated Injury Scale_head ≥5, prehospital cardiopulmonary resuscitation, and a prehospital blood pressure of <90 mm Hg. In terms of good early neurologic outcomes, no differences were recorded between the BMI groups (range 59.0%-62.6%, P = 0.087).

CONCLUSIONS

In this study a BMI ≥35 is an independent predictor of mortality and is associated with an inferior early functional neurologic outcome.

Trauma and BMI Mortality

PURPOSE OF REVIEW

Obesity has been recognized as an impactful comorbid condition. It has been demonstrated to be an independent risk factor for morbidity and mortality following trauma.

RECENT FINDINGS

Multiple studies and reviews have strongly suggested obesity to be associated with increased risk for post-injury morbidity and mortality. As obesity is associated with a pro-inflammatory state, it has been suggested to negatively affect the respiratory, cardiovascular, coagulation, and renal systems and the ability and manner in which an obese patient heals. As obesity continues to rise at alarming rates in the USA, this population of patients requires special consideration and continued research is underway to delineate relationships between obesity, trauma, and outcomes in an effort to improve overall care.

Demand for specialised training for the obese trauma patient: National ATLS expert group survey results

BACKGROUND

The growing incidence of obesity in Western populations continues to place new stressors on health systems. Obese trauma patients present particular challenges across the entirety of the patient care pathway, and are at risk of higher lengths of stay, morbidity, and mortality. This study sought to assess a national group of trauma experts' opinions and knowledge regarding the management of obese trauma.

METHODS

A questionnaire was circulated to a trauma training providers and national steering committee members at a UK national Advance Trauma Life Support meeting. Demographic, knowledge, and opinion data was collected and collated for analysis.

RESULTS

109 questionnaires were returned (73% response rate). Broad agreement was reached that obese trauma patients were more challenging to manage (96.2% agreement) and suffered worse outcomes (89.9%). Only 22.2% felt their hospitals possessed appropriate resources to facilitate management. Up to a third of respondents had personally witnesses errors in care due to patient obesity. 90% believed specialist training for obese trauma could improve care.

DISCUSSION

There is broad consensus amongst UK trauma providers that obese trauma patients are at risk of poorer outcomes and errors in care. Knowledge and preparedness of centres to manage these patients is variable. There was broad consensus that specialist training for the management of obese trauma patients may improve outcomes.

Analysis of Mortality in Traumatically Injured Patients Based on Body Mass Index and Mechanism Reveals Highest Mortality among the Underweight in Comparison with the Ideal Weight Patients

The purpose of this study was to evaluate the effect of body mass index (BMI) on mortality after traumatic injury. The records of patients from 2012 to 2015 were retrospectively reviewed. The patients were stratified into the following groups based on admission BMI (kg/m2): underweight (UW) (BMI <19), ideal weight (IW) (BMI = 19–24.9), overweight (OW) (BMI = 25–29.9), obese (OB) (BMI = 30–39.9), and morbid obese (MO) (BMI >40). The groups were well matched with no significant differences in demographics and Injury Severity Score. Morality for the IW group was compared with the remaining BMI groups. A total of 6049 patients were identified. In comparison with IW group, the UW mortality was significantly higher (IW vs UW, 4.1% vs 8.8%, P = 0.001); however, the there was no significant difference with remaining groups. There was also no significant difference in mortality between IW and the remaining groups for patients that went directly to the operating room or for patients that had penetrating trauma (stab wounds and gunshot wounds). However, for blunt trauma, the mortality was significantly higher for UW (IW vs UW, 4.3% vs 9.4%, P = 0.001), no different for IW vs OW (4.3% vs 3.7%, P = 0.3), and significantly lower for IW vs OB (4.3% vs 2.8%, P = 0.04) and for IW vs MO (4.3% vs 1.0%, P = 0.03). After traumatic injuries, it is the underweight patients (BMI <19) and not the obese, that are at a significantly higher risk for overall mortality; this difference is especially evident after blunt trauma where obesity may actually confer a protective role.

The influence of tracheostomy timing on outcomes in trauma patients: A meta-analysis

OBJECTIVE

This study aims to assess the influence of tracheostomy timing on outcomes among trauma patients, including mortality, medical resource utility and incidence of pneumonia.

METHOD

A systematic review of the literature was conducted by internet search. Data were extracted from selected studies and analyzed using Stata to compare outcomes in trauma patients with early tracheostomy (ET) or late tracheostomy (LT)/prolonged intubation (PI).

RESULT

20 studies met our inclusion criteria with 3305 patients in ET group and 4446 patients in LT/PI group. Pooled data revealed that mortality was not lower in trauma patients with ET compared to those with LT/IP. However, ET was found to be associated with a significantly reduced length of ICU and hospital stay, shorter MV duration and lower risk of pneumonia.

CONCLUSION

Evidence of this meta-analysis supports the dimorphism in some clinical outcomes of trauma patients with different tracheostomy timing. Additional well-designed randomized controlled trials (RCTs) are needed to confirm it in future.

The effects of body mass index on complications and mortality after emergency abdominal operations: The obesity paradox

BACKGROUND

Recent literature suggests that obesity is protective in critically illness. This study addresses the effect of BMI on outcomes after emergency abdominal surgery (EAS).

METHODS

Retrospective, ACS-NSQIP analysis. All patients that underwent EAS were included. The study population was divided into five groups based on BMI; regression models were used to evaluate the role of obesity in morbidity and mortality.

RESULTS

101,078 patients underwent EAS; morbidity and mortality were 19.5% and 4.5%, respectively. Adjusted mortality was higher in underweight patients (AOR 1.92), but significantly lower in all obesity groups (AOR's 0.73, 0.66, 0.70, 0.70 respectively). Underweight and class III obesity was associated with increased complications (AOR 1.47 and 1.30), while mild obesity was protective (AOR 0.92).

CONCLUSIONS

Underweight patients undergoing EAS have increased morbidity and mortality. Although class III obesity is associated with increased morbidity, overweight and class I obesity were protective. All grades of obesity may be protective against mortality after EAS relative to normal weight patients.

OBESITY AND CRITICAL ILLNESS: INSIGHTS FROM ANIMAL MODELS

Critical illness is a major cause of morbidity and mortality around the world. While obesity is often detrimental in the context of trauma, it is paradoxically associated with improved outcomes in some septic patients. The reasons for these disparate outcomes are not well understood. A number of animal models have been used to study the obese response to various forms of critical illness. Just as there have been many animal models that have attempted to mimic clinical conditions, there are many clinical scenarios that can occur in the highly heterogeneous critically ill patient population that occupies hospitals and intensive care units. This poses a formidable challenge for clinicians and researchers attempting to understand the mechanisms of disease and develop appropriate therapies and treatment algorithms for specific subsets of patients, including the obese. The development of new, and the modification of existing animal models, is important in order to bring effective treatments to a wide range of patients. Not only do experimental variables need to be matched as closely as possible to clinical scenarios, but animal models with pre-existing comorbid conditions need to be studied. This review briefly summarizes animal models of hemorrhage, blunt trauma, traumatic brain injury, and sepsis. It also discusses what has been learned through the use of obese models to study the pathophysiology of critical illness in light of what has been demonstrated in the clinical literature.

The Critical Care Obesity Paradox and Implications for Nutrition Support

Obesity is a leading cause of preventable death worldwide. The prevalence of obesity has been increasing and is associated with an increased risk for other co-morbidities. In the critical care setting, nearly one third of patients are obese. Obese critically ill patients pose significant physical and on-physical challenges to providers, including optimization of nutrition therapy. Intuitively, obese patients would have worse critical care-related outcome. On the contrary, emerging data suggests that critically ill obese patients have improved outcomes, and this phenomenon has been coined "the obesity paradox." The purposes of this review will be to outline the historical views and pathophysiology of obesity and epidemiology of obesity, describe the challenges associated with obesity in the intensive care unit setting, review critical care outcomes in the obese, define the obesity-critical care paradox, and identify the challenges and role of nutrition support in the critically ill obese patient.

Traumatic injuries among adult obese patients in southern Taiwan: a cross-sectional study based on a trauma registry system

BACKGROUND

The adverse impact of obesity has been extensively studied in the general population; however, the added risk of obesity on trauma-related mortality remains controversial. This study investigated and compared mortality as well injury patterns and length of stay (LOS) in obese and normal-weight patients hospitalized for trauma in the hospital and intensive care unit (ICU) of a Level I trauma center in southern Taiwan.

METHODS

Detailed data of 880 obese adult patients with body mass index (BMI) ≥ 30 kg/m(2) and 5391 normal-weight adult patients (25 > BMI ≥ 18.5 kg/m(2)) who had sustained a trauma injury between January 1, 2009 and December 31, 2013 were retrieved from the Trauma Registry System. Pearson's chi-squared, Fisher's exact, and independent Student's t-tests were used to compare differences between groups. Propensity score matching with logistic regression was used to evaluate the effect of obesity on mortality.

RESULTS

In this study, obese patients were more often men, motorcycle riders and pedestrians, and had a lower proportion of alcohol intoxication compared to normal-weight patients. Analysis of Abbreviated Injury Scale scores revealed that obese trauma patients presented with a higher rate of injury to the thorax, but a lower rate of facial injuries than normal-weight patients. No significant differences were found between obese and normal-weight patients regarding Injury Severity Score (ISS), Trauma-Injury Severity Score (TRISS), mortality, the proportion of patients admitted to the ICU, or LOS in ICU. After propensity score matching, logistic regression of 66 well-matched pairs did not show a significant influence of obesity on mortality (odds ratio: 1.51, 95% confidence interval: 0.54-4.23 p = 0.438). However, significantly longer hospital LOS (10.6 vs. 9.5 days, respectively, p = 0.044) was observed in obese patients than in normal-weight patients, particularly obese patients with pelvic, tibial, or fibular fractures.

CONCLUSION

Compared to normal-weight patients, obese patients presented with different injury characteristics and bodily injury patterns but no difference in mortality.

The impact of tree-stand falls on a Level 1 trauma center in West Michigan

BACKGROUND

Falls from tree stands are common during the hunting season. We examined the impact of this injury mechanism on a Level 1 trauma center in West Michigan.

METHODS

Retrospective cohort study examining tree-stand fall patients between 2001 and 2013.

RESULTS

A total of 193 patients were included. Less than 3% of patients were wearing a harness. Falls from greater than 20 feet were associated with a higher injury severity score (P = .018). The injury severity score and Glasgow coma scale of the normal weight and overweight (OW) groups were the same. Overall 91.3% of normal weight patients were discharged home vs 63.5% of OW patients (P = .009). Median rehab stay was 12 days (3 to 92), and median charge was $24,048 (2,398 to 134,752).

CONCLUSIONS

Tree-stand falls cause significant injury, especially from heights greater than 20 feet. OW patients more frequently require rehabilitation. The infrequent use of safety harnesses is alarming.

Body Morphology and Its Associations With Thoracolumbar Trauma Sustained in Motor Vehicle Collisions

OBJECTIVE

This study investigates the relationship between body mass index (BMI) and the patterns of thoracolumbar spinal fractures sustained by patients in motor vehicle collisions (MVCs).

DESIGN

The Crash Injury Research and Engineering Network (CIREN) database was used to analyze prospective data on patients involved in MVCs of moderate severity.

METHODS

Thoracolumbar fractures in 631 subjects were analyzed for patient-, vehicle-, and crash-related factors. Spine injuries were classified according to a modified Denis classification system. Subjects were stratified into BMI subgroups that were then analyzed by injury level, fracture pattern, associated systemic injury, and mortality.

RESULTS

Obesity (BMI ≥ 30.0) was found to be associated with a more cephalad level of injury. Mean BMI was higher in 67 patients with fatal outcomes compared with 557 survivors. Patients who sustained a thoracolumbar fracture and another system injury were more likely to be overweight and obese. Among the various fracture patterns analyzed, BMI was highest in patients with extension injuries.

CONCLUSION

This study characterizes the relationship between body morphology and the thoracolumbar injury patterns associated with MVC to improve understanding of the overall morbidity and mortality of these injuries. These results corroborate research demonstrating the unique relationships between patients who are obese and specific patterns of injury and higher injury severity caused by MVCs and establish a rationale for specifically including thoracolumbar spine parameters in crash safety standards.

Management of the Open Abdomen in Obese Trauma Patients

Obesity incidence in the trauma population is increasing. Abdominal compartment syndrome has poor outcomes when left untreated. Surgeons may treat obese patients differently because of concern for increased morbidity and mortality. We studied the effects of body mass index (BMI) on resource utilization and outcome. An Institutional Review Board-approved retrospective review of trauma patients requiring temporary abdominal closure (TAC) was performed. Patients were stratified as follows: Group 1-BMI = 18.5 to 24.9 kg/m2, Group 2-BMI = 25 to 29.9 kg/m2, Group 3-BMI = 30 to 39.9 kg/m2, Group 4-BMI ≥ 40 kg/m2. Demographic data, illness severity as defined by Injury Severity Score, Acute Physiology and Chronic Health Evaluation Score Version II and Simplified Acute Physiology Score Version II scores, resource utilization, fascial closure rate, and survival were collected. About 380 patients required TAC. Median age of Group 1 was significantly lower than Groups 2 and 3 ( P = 0.001). Severity of illness did not differ. Group 4 had a longer intensive care unit stay compared with Groups 1 and 2 ( P = 0.005). Group 4 required mechanical ventilation longer than Group 1 ( P = 0.027). Hospital stay, fascial closure, and survival were equivalent. Obese trauma patients with TAC have a longer intensive care unit stay and more ventilator days, but there is no difference in survival or type of closure. TAC can be used safely in trauma patients with a BMI ≥ 30 kg/m2.

The impact of hyperglycemia and obesity on hospitalization costs and clinical outcome in general surgery patients

BACKGROUND

The impact of obesity on clinical outcomes and hospitalization costs in general surgery patients with and without diabetes (DM) is unknown.

MATERIALS AND METHODS

We reviewed medical records of 2451 patients who underwent gastrointestinal surgery at two university hospitals. Hyperglycemia was defined as BG ≥140 mg/dl. Overweight was defined by body mass index (BMI) between 25-29.9 kg/m(2) and obesity as a BMI ≥30 kg/m(2). Hospital cost was calculated using cost-charge ratios from Centers for Medicare and Medicaid Services. Hospital complications included a composite of major cardiovascular events, pneumonia, bacteremia, acute kidney injury (AKI), respiratory failure, and death.

RESULTS

Hyperglycemia was present in 1575 patients (74.8%). Compared to patients with normoglycemia, those with DM and non-DM with hyperglycemia had higher number of complications (8.9% vs. 35.8% vs. 30.0%, p<0.0001), longer hospital stay (5 days vs. 9 days vs. 9 days, p<0.0001), more readmissions within 30 days (9.3% vs. 18.8% vs. 17.2%, p<0.0001), and higher hospitalization costs ($20,273 vs. $79,545 vs. $72,675, p<0.0001). In contrast, compared to normal-weight subjects, overweight and obesity were not associated with increased hospitalization costs ($58,313 vs. $58,173 vs. $66,633, p=0.74) or risk of complications, except for AKI (11.9% vs. 14.8% vs. 20.5%, p<0.0001). Multivariate analysis revealed that DM (OR=4.4, 95% CI=2.8,7.0) or perioperative hyperglycemia (OR=4.1, 95% CI=2.7-6.2) were independently associated with increased risk of complications.

CONCLUSION

Hyperglycemia but not increasing BMI, in patients with and without diabetes undergoing gastrointestinal surgery was associated with a higher number of complications and hospitalization costs.

The Epidemiology of Obesity: A Big Picture

The epidemic of overweight and obesity presents a major challenge to chronic disease prevention and health across the life course around the world. Fueled by economic growth, industrialization, mechanized transport, urbanization, an increasingly sedentary lifestyle, and a nutritional transition to processed foods and high-calorie diets over the last 30 years, many countries have witnessed the prevalence of obesity in its citizens double and even quadruple. A rising prevalence of childhood obesity, in particular, forebodes a staggering burden of disease in individuals and healthcare systems in the decades to come. A complex, multifactorial disease, with genetic, behavioral, socioeconomic, and environmental origins, obesity raises the risk of debilitating morbidity and mortality. Relying primarily on epidemiologic evidence published within the last decade, this non-exhaustive review discusses the extent of the obesity epidemic, its risk factors-known and novel-, sequelae, and economic impact across the globe.

Oxidative stress contributes to orthopedic trauma-induced acute kidney injury in obese rats

After trauma, obese patients have an increased risk of developing acute kidney injury (AKI). We have demonstrated that obese Zucker (OZ) rats, but not lean Zucker (LZ) rats, develop AKI 24 h after orthopedic trauma. ROS have been implicated in the pathophysiology of AKI in models of critical illness. However, the contribution of ROS to trauma-induced AKI in the setting of obesity has not been determined. We hypothesized that AKI in OZ rats after trauma is mediated by increased oxidative stress. Male LZ and OZ rats were divided into control and trauma groups, with a subset receiving treatment after trauma with the antioxidant apocynin (50 mg/kg ip, 2 mM in drinking water). The day after trauma, glomerular filtration rate, plasma creatinine, urine kidney injury molecule-1, and albumin excretion as well as renal oxidant and antioxidant activity were measured. After trauma, compared with LZ rats, OZ rats exhibited a significant decrease in glomerular filtration rate along with significant increases in plasma creatinine and urine kidney injury molecule-1 and albumin excretion. Additionally, oxidative stress was significantly increased in OZ rats, as evidenced by increased renal NADPH oxidase activity and urine lipid peroxidation products (thiobarbituric acid-reactive substances), and OZ rats also had suppressed renal superoxide dismutase activity. Apocynin treatment significantly decreased oxidative stress and AKI in OZ rats but had minimal effects in LZ rats. These results suggest that ROS play an important role in AKI in OZ rats after traumatic injury and that ROS may be a potential future therapeutic target in the obese after trauma.

Perioperative and acute care outcomes in morbidly obese patients with acetabular fractures at a Level 1 trauma center

BACKGROUND

Controversy exists regarding obesity-related injury severity and clinical outcomes after orthopedic trauma.

PURPOSE

The purposes of this study were to expand our understanding of the effect of morbid obesity on perioperative and acute care outcomes after acetabular fracture.

METHODS

This was a retrospective review of patients with acetabular fracture after trauma. Non-morbidly obese (BMI < 35 kg/m(2)) and morbidly obese (BMI ≥ 35 kg/m(2); N = 81). Injury severity scores and Glasgow Coma Scale scores (GCS) were collected. Perioperative and acute care outcomes were positioning and operative time, extra fractures, estimated blood loss, complications, hospital charges, ventilator days, transfusions, length of stay (LOS) and discharge destination. Positioning and operative times were longer in morbidly obese patients (p < 0.05). No other differences existed between groups.

CONCLUSIONS

Orthopedic trauma surgeons and care teams can expect similar acute care outcomes in morbidly obese and non-morbidly obese patients with acetabular fracture.

Obesity does not increase mortality after emergency surgery

OBJECTIVE

The aim of this study is to evaluate the impact of obesity on patient outcomes after emergency surgery.

METHODS

A list of all patients undergoing emergent general surgical procedures during the 12 months ending in July 2012 was obtained from the operating room log. A chart review was performed to obtain the following data: patient characteristics (age, gender, BMI, and preexisting comorbidities), indication for surgery, and outcomes (pulmonary embolus (PE), deep venous thrombosis (DVT), respiratory failure, ICU admission, wound infection, pneumonia, and mortality). Obesity was defined as a BMI over 25. Comparisons of outcomes between obese and nonobese patients were evaluated using Fischer's exact test. Predictors of mortality were evaluated using logistic regression.

RESULTS

341 patients were identified during the study period. 202 (59%) were obese. Both groups were similar in age (48 for obese versus 47 for nonobese, P = 0.42). Obese patients had an increased incidence of diabetes, (27% versus 7%, P < 0.05), hypertension (52% versus 34%, P < 0.05), and sleep apnea (0% versus 5%, P < 0.05). There was a statistically significant increased incidence of postoperative wound infection (obese 9.9% versus nonobese 4.3%, P < 0.05) and ICU admission (obese 58% versus nonobese 42%, P = 0.01) among the obese patients. Obesity alone was not shown to be a significant risk factor for mortality.

CONCLUSIONS

A higher BMI is not an independent predictor of mortality after emergency surgery. Obese patients are at a higher risk of developing wound infections and requiring ICU admission after emergent general surgical procedure.

A novel experimental model of orthopedic trauma with acute kidney injury in obese Zucker rats

Obesity is associated with an increased risk of acute kidney injury (AKI) after blunt traumatic injury in humans. Because limitations exist in studying trauma in human patients, animal models are necessary to elucidate mechanisms of remote organ injury after trauma. We developed a model of severe orthopedic trauma in lean (LZ) and obese (OZ) Zucker rats, in which OZ develop greater kidney dysfunction after trauma than LZ. Orthopedic trauma was inflicted via bilateral hindlimb soft tissue injury, fibula fracture, and injection of homogenized bone components. Mean arterial pressure (MAP) and heart rate (HR) were measured for 6 h after trauma, and again at 24 h after trauma. Urine was collected for 24 h before and after trauma to measure urine albumin excretion. Glomerular filtration rate (GFR), renal plasma flow (RPF), plasma interleukin-6 (IL-6), and renal macrophage infiltration (ED-1 [CD68 Antibody] immunostaining) were measured in animals with and without trauma. MAP and HR were similar between LZ and OZ throughout the study, with the exception that OZ had a 18 mmHg lower pressure 24 h posttrauma. GFR and RPF were decreased significantly (∼50%), while urine albumin excretion, plasma IL-6, and renal ED-1-positive cells were increased in OZ 24 h after trauma compared to both OZ without trauma and LZ after trauma. In conclusion, these data are consistent with studies in humans that show that AKI develops more frequently in obese than in lean individuals. This model will be an important experimental tool to better understand the underlying mechanisms of poor outcomes after trauma in obese patients.