Regan J. Berg
University of Southern California
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Journal of Trauma-injury Infection and Critical Care | 2014
Regan J. Berg; Efstathios Karamanos; Kenji Inaba; Obi Okoye; Pedro G. Teixeira; Demetrios Demetriades
BACKGROUND Penetrating thoracoabdominal trauma, with potential injury to two anatomic cavities, significantly challenges surgical management, yet this injury pattern has not been reviewed across a large patient series. METHODS The trauma registry of a major level 1 center was queried for all adult patients admitted with thoracoabdominal stab wounds between January 1996 and December 2011. RESULTS The study identified 617 patients; 11% arrived hypotensive (systolic blood pressure < 90 mm Hg), 6.5% had Glasgow Coma Scale (GCS) score less than 8, and 3.6% were in cardiac arrest. Of those arriving alive, 350 (59%) of 595 underwent surgery (88% laparotomy, 3% thoracotomy, and 9% both procedures). Nontherapeutic laparotomy was performed on 12.3% of these patients. Cardiac injury occurred in 71% (29 of 41) of the patients arriving alive undergoing thoracotomy. Among this group, only 1 (2.4%) of 41 had a major thoracic vessel or aortic injury without cardiac trauma. Diaphragmatic injury (DI) occurred in 224 (38%) of 595, with 72 (32.1%) of these 224 demonstrating no computed tomographic evidence of DI. Either hollow viscus injury or DI occurred in 50%. Only 36.8% of liver, 58% of spleen, and 29.8% of kidney injuries required surgical repair. The need for dual-cavitary intervention was associated with a precipitous increase in patient mortality. CONCLUSION Patients with thoracoabdominal stab wounds present considerable clinical challenges due to high surgical need, high occult DI incidence, persistently high rates of negative laparotomy, and significant mortality with dual-cavitary intervention. Many patients with solid-organ injuries do not require intervention. High incidence of hollow viscus injury and DI ultimately limits nonoperative management. Laparoscopy is necessary to exclude occult DI. In unstable patients, determination of which anatomic cavity to explore primarily requires exclusion of cardiac injury. In those with equivocal clinical or ultrasonographic evidence of cardiac trauma, laparotomy, with transdiaphragmatic pericardial window, if a causative abdominal injury is not immediately apparent, seems the most effective strategy. LEVEL OF EVIDENCE Epidemiologic study, level III.
Surgery | 2015
Regan J. Berg; Kenji Inaba; Maura E. Sullivan; Obi Okoye; Stefano Siboni; Michael Minneti; Pedro G.R. Teixeira; Demetrios Demetriades
BACKGROUND Increasing ambient temperature to prevent intraoperative patient hypothermia remains widely advocated despite unconvincing evidence of efficacy. Heat stress is associated with decreased cognitive and psychomotor performance across multiple tasks but remains unexamined in an operative context. We assessed the impact of increased ambient temperature on laparoscopic operative performance and surgeon cognitive stress. STUDY DESIGN Forty-two performance measures were obtained from 21 surgery trainees participating in the counter-balanced, within-subjects study protocol. Operative performance was evaluated with adaptations of the validated, peg-transfer, and intracorporeal knot-tying tasks from the Fundamentals of Laparoscopic Surgery program. Participants trained to proficiency before enrollment. Task performance was measured at two ambient temperatures, 19 and 26°C (66 and 79°F). Participants were randomly counterbalanced to initial hot or cold exposure before crossing over to the alternate environment. Cognitive stress was measured using the validated Surgical Task Load Index (SURG-TLX). RESULTS No differences in performance of the peg-transfer and intracorporeal knot-tying tasks were seen across ambient conditions. Assessed via use of the six bipolar scales of the SURG-TLX, we found differences in task workload between the hot and cold conditions in the areas of physical demands (hot 10 [3-12], cold 5 [2.5-9], P = .013) and distractions (hot 8 [3.5-15.5], cold 3 [1.5-5.5], P = .001). Participant perception of distraction remained greater in the hot condition on full scoring of the SURG-TLX. CONCLUSION Increasing ambient temperature to levels advocated for prevention of intraoperative hypothermia does not greatly decrease technical performance in short operative tasks. Surgeons, however, do report increased perceptions of distraction and physical demand. The impact of these findings on performance and outcomes during longer operative procedures remains unclear.
Injury-international Journal of The Care of The Injured | 2014
Regan J. Berg; Kenji Inaba; Obi Okoye; Jason Pasley; Pedro G.R. Teixeira; Michael Esparza; Demetrios Demetriades
INTRODUCTION Selective non-operative management (NOM) is standard of care for clinically stable patients with blunt splenic trauma and expectant management approaches are increasingly utilised in penetrating abdominal trauma, including in the setting of solid organ injury. Despite this evolution of clinical practice, little is known about the safety and efficacy of NOM in penetrating splenic injury. METHODS Trauma registry and medical record review identified all consecutive patients presenting to LAC+USC Medical Center with penetrating splenic injury between January 2001 and December 2011. Associated injuries, incidence and nature of operative intervention, local and systemic complications and mortality were determined. RESULTS During the study period, 225 patients experienced penetrating splenic trauma. The majority (187/225, 83%) underwent emergent laparotomy. Thirty-eight clinically stable patients underwent a deliberate trial of NOM and 24/38 (63%) were ultimately managed without laparotomy. Amongst patients failing NOM, 3/14 (21%) underwent splenectomy while an additional 6/14 (42%) had splenorrhaphy. Hollow viscus injury (HVI) occurred in 21% of all patients failing NOM. Forty percent of all NOM patients had diaphragmatic injury (DI). All patients undergoing delayed laparotomy for HVI or a splenic procedure presented symptomatically within 24h of the initial injury. No deaths occurred in patients undergoing NOM. CONCLUSIONS Although the vast majority of penetrating splenic trauma requires urgent operative management, a group of patients does present without haemodynamic instability, peritonitis or radiologic evidence of hollow viscus injury. Management of these patients is complicated as over half may remain clinically stable and can avoid laparotomy, making them potential candidates for a trial of NOM. HVI is responsible for NOM failure in up to a fifth of these cases and typically presents within 24h of injury. Delayed laparotomy, within this limited time period, did not appear to increase mortality nor preclude successful splenic salvage. In clinically stable patients, diagnostic laparoscopy remains essential to evaluate and repair occult DI. As NOM for penetrating abdominal trauma becomes more common, multi-centre data is needed to more accurately define the principles of patient selection and the limitations and consequences of this approach in the setting of splenic injury.
Archives of Surgery | 2012
Regan J. Berg; Obi Okoye; Pedro G. Teixeira; Kenji Inaba; Demetrios Demetriades
OBJECTIVES To examine the specific injuries, need for operative intervention, and clinical outcomes of patients with blunt thoracoabdominal trauma. DESIGN Trauma registry and medical record review. SETTING Level I trauma center in Los Angeles, California. PATIENTS All patients with thoracoabdominal injuries from January 1996 to December 2010. MAIN OUTCOME MEASURES Injuries, incidence and type of operative intervention, clinical outcomes, and risk factors for mortality. RESULTS Blunt thoracoabdominal injury occurred in 1661 patients. Overall, 474 (28.5%) required laparotomy, 31 (1.9%) required thoracotomy (excluding resuscitative thoracotomy), and 1146 (69.0%) required no thoracic or abdominal operation. Overall incidence of intraabdominal solid organ injury was 59.7% and hollow viscus injury, 6.0%. Blunt cardiac trauma occurred in 6.3%; major thoracic vessel injury, in 4.6%; and diaphragmatic trauma, in 6.0%. The majority of solid organ injuries were managed nonoperatively (liver, 83.9%; spleen, 68.3%; and kidney, 91.2%). Excluding patients with severe head trauma, mortality ranged from 4.5% with nonoperative management to 18.1% and 66.7% in those requiring laparotomy and dual cavitary exploration, respectively. Age 55 years or older, Injury Severity Score of 25 or more, Glasgow Coma Scale score of 8 or less, initial hypotension, massive transfusion, and liver, cardiac, or abdominal vascular trauma were all independent risk factors for mortality. CONCLUSIONS Most patients with blunt thoracoabdominal trauma are managed nonoperatively. The need for non-resuscitative thoracotomy or combined thoracoabdominal operation is rare. The abdomen contains the overwhelming majority of injuries requiring operative intervention and should be the initial cavity of exploration in the patient requiring emergent surgery without directive radiologic data.
Journal of Trauma-injury Infection and Critical Care | 2012
Kenji Inaba; Regan J. Berg; Galinos Barmparas; Peter Rhee; Gregory J. Jurkovich; Gustavo Recinos; Pedro G. Teixeira; Demetrios Demetriades
BACKGROUND Although uncomfortable for the operating team, trauma operating room (OR) temperatures have traditionally been kept warm in an attempt to mitigate intraoperative heat loss. The purpose of this study was to examine how ambient OR temperatures impact core temperature in patients undergoing emergent surgery for trauma. METHODS Injured adult patients requiring emergent surgery at a Level 1 trauma center were prospectively enrolled between July 2008 and January 2010. Standardized warming measures were used for all patients. Ambient OR temperature was recorded in 5-minute intervals with the Fourier Microlog EC600 temperature data logger. Intraoperative core patient temperatures were compared with ambient OR temperature. Patients experiencing intraoperative core temperature decreases were compared with those who did not, to examine the impact of ambient temperature changes on the risk of perioperative hypothermia. RESULTS During the 18-month study period, 118 patients requiring emergent surgery (73% laparotomy, 5% thoracotomy, 7% combined, 15% other) were enrolled. Incidence of hypothermia (<35°C) at admission to the OR was 29.7%. Crude mortality increased as the final patient core temperature achieved in the OR decreased (4.2% for temperatures >35°C and as high as 50% for temperatures ⩽32°C). Overall, core temperature decreased in 46 patients (39.0%) but remained stable or increased by the end of the procedure in 72 (61%). There were no significant differences in the admission temperature, clinical demographics, or volume of fluids and blood products between the two groups. In a forward logistic regression analysis, a lower ambient OR temperature was not associated with a drop in the patient’s core temperature. CONCLUSION In this prospective study, the ambient OR temperature did not affect the core temperature of injured patients undergoing emergent surgery. LEVEL OF EVIDENCE Prognostic study, level III; therapeutic study, level IV.
Journal of Trauma-injury Infection and Critical Care | 2014
Regan J. Berg; Kenji Inaba; Obi Okoye; Efstathios Karamanos; Aaron Strumwasser; Konstantinos Chouliaras; Pedro G. Teixeira; Demetrios Demetriades
BACKGROUND Thoracoabdominal firearm injuries present major diagnostic and therapeutic challenges because of the risk for potential injury in multiple anatomic cavities and the attendant dilemma of determining the need for and correct sequencing of cavitary intervention. Injury patterns, management strategies, and outcomes of thoracoabdominal firearm trauma remain undescribed across a large population. METHODS All patients with thoracoabdominal firearm injury admitted to a major Level I trauma center during a 16-year period were reviewed. RESULTS The 984 study patients experienced severe injury burden; 25% (243 of 984) presented in cardiac arrest, and 75% (741 of 984) had an Abbreviated Injury Scale (AIS) score of 3 or greater in both the chest and the abdomen. Operative management occurred in 86% (638 of 741). Of the patients arriving alive, 68% (507 of 741) underwent laparotomy alone, 4% (27 of 741) underwent thoracotomy alone, and 14% (104 of 741) underwent dual-cavitary intervention. Negative laparotomy occurred in 3%. Diaphragmatic injury (DI) occurred in 63%. Seventy-five percent had either DI or hollow viscus injury. Cardiac injury was present in 33 patients arriving alive. Despite the use of trauma bay ultrasound, 44% of the patients with cardiac injury underwent initial laparotomy. In half of this group, ultrasound did not detect pericardial blood. The need for thoracotomy, either alone or as part of dual-cavitary intervention, was the strongest independent risk factor for mortality in those arriving alive. CONCLUSION Greater kinetic destructive potential drives the peril of thoracoabdominal firearm trauma, producing clinical challenges qualitatively and quantitatively different from nonfirearm injuries. Severe injury, on both sides of the diaphragm, generates high operative need with low rates of negative exploration. The need for emergent intervention and a high incidence of DI or hollow viscus injury limit opportunity for nonoperative management. Even with ultrasound, emergent preoperative diagnosis remains challenging, as the complex combination of intra-abdominal, thoracic, and diaphragmatic injuries can provoke misinterpretation of both radiologic and clinical data. Successful emergent management requires thorough assessment of all anatomic spaces, integrating ultrasonographic, radiologic, and clinical findings. LEVEL OF EVIDENCE Epidemiologic study, level III.
Trauma | 2011
Regan J. Berg; Peep Talving; Kenji Inaba
Cardiac rupture is the most extreme manifestation of blunt cardiac injury. In the first half of the 20th century this lesion was uniformly fatal. Since the first successful post-traumatic cardiorrhaphy by Desforges in 1955, multiple case reports and retrospective reviews have documented successful operative repair and survival of patients with this injury. Despite these successes, blunt cardiac rupture remains associated with a high mortality rate. The rarity of this condition and the heterogeneity of the literature make determination of exact epidemiologic data difficult. The classic clinical presentation is not universal and a subset of patients may present asymptomatically. Rapid transportation to medical care, accurate timely diagnosis and emergent operative intervention are essential for successful outcome. The use of ultrasonography in the trauma bay is a key component of early identification of these injuries. Specific outcome factors associated with survival are difficult to determine and even in those who survive to medical attention mortality rates remain as high as 60—90%.
Journal of Trauma-injury Infection and Critical Care | 2017
Nicole Mansfield; Kenji Inaba; Regan J. Berg; Elizabeth Beale; Elizabeth Benjamin; Lydia Lam; Kazuhide Matsushima; Demetrios Demetriades
BACKGROUND Early pancreatic dysfunction after resection in trauma has not been well characterized. The objective of this study was to examine the incidence and clinical impact of new-onset endocrine and exocrine dysfunction after pancreatic resection for trauma. METHODS All patients sustaining a pancreatic injury from 1996 to 2013 were identified. Patients with preinjury diabetes were excluded. Survivors were divided into three groups according to the extent of anatomic resection—distal, proximal, or total pancreatectomy. Clinical demographics and outcome data were abstracted. Blood glucose levels, hemoglobin A1c, and insulin requirements were used to assess endocrine pancreatic function. Reported steatorrhea, diarrhea, or supplemental pancreatic enzyme requirements were used to assess exocrine pancreatic function. RESULTS During the study period, 331 pancreatic injuries were identified, of which 109 (33%) required resection and 84 survived to hospital discharge. Four were excluded. Of 80 cases analyzed, 73 (91%) underwent distal pancreatectomy, 7 (9%) proximal pancreatectomy, and none a total pancreatectomy. The distal resection group was predominantly male (88%), median age 24 years, and mean BMI 27 (kg/m2). Thirty-eight (52%) required insulin postoperatively, with the greatest proportion (47%) requiring insulin for ⩽1 day; no patients were discharged on insulin. The proximal resection group was predominantly male (86%), median age 31 years, and mean BMI 32 (kg/m2). Six of seven required insulin postoperatively and two of seven were insulin dependent at time of hospital discharge. For both distal and proximal resections, none had evidence of exocrine dysfunction or received pancreatic enzyme supplementation at discharge. CONCLUSION Exocrine dysfunction after distal or proximal pancreatectomy for trauma is rare. The incidence of early onset endocrine dysfunction after traumatic distal pancreatectomy is also rare; however, it can be seen after proximal resection. Level of Evidence Therapeutic study, level IV.
Trauma | 2014
Nicolas Melo; Regan J. Berg; Kenji Inaba
Although generally a safe activity with considerable health benefit, the wide social prevalence of cycling, its performance by both young and elderly riders, and the increasing operation of bicycles in complex urban environments results in a significant incidence of trauma. Orthopedic injuries, followed by head and facial trauma, are most frequent but all anatomic regions can be affected and the spectrum of injury ranges from minor to severe and potentially fatal. Clinicians need to be aware of the range of injuries and causative mechanisms as many patients may present with relatively minor signs and symptoms despite significant underlying pathology. Non-commuter, recreational cyclists are also at risk for injury due to: variable terrain and environmental conditions; increased competitive and risk-taking behavior; technical equipment failure; and poor compliance with protective equipment. Numerous injury preventative strategies have been advocated including: increased rider training; creation of dedicated traffic lanes for commuting cyclists; bike-awareness education for motorists and interventions to improve cyclist visibility; increased utilization of protective equipment and programs to reduce concomitant drug or alcohol use. Of all preventative strategies, bicycle helmets have received the most study, leading to legislated use in some jurisdictions. As urban environments become more congested for commuter cyclists, and interest in recreational and competitive cycling grows, bicycle injury is likely to become more prevalent.
Digestive Surgery | 2017
Efstathios Karamanos; Kenji Inaba; Regan J. Berg; Shelby Resnick; Obi Okoye; Sophoclis Alexopoulos; Konstantinos Chouliaras; Demetrios Demetriades
Background: Aging has been associated with increasing common bile duct (CBD) diameter and reported as independently predictive of the likelihood of choledocolithiasis. These associations are controversial with uncertain diagnostic utility in patients presenting with symptomatic disease. The current study examined the relationship between age, CBD size, and the diagnostic probability of choledocolithiasis. Methods: Symptomatic patients undergoing evaluation for suspected choledocolithiasis from January 2008 to February 2011 were reviewed. In the cohort without choledocolithiasis, the relationship between aging and CBD size was examined as a continuous variable and by comparing mean CBD size across stratified age groups. Multivariate analysis examined the relationship between increasing age and diagnostic probability of choledocolithiasis in all patients. Results: Choledocolithasis was diagnosed by MR cholangiopancreatography (MRCP) or endoscopic retrograde (ERCP) in 496 of 1,000 patients reviewed. Mean CBD was 6.0 mm (±2.8 mm) in the 504 of 1,000 patients without choledocolithiasis on ERCP/MRCP. Increasing age had no correlation with CBD size as a continuous variable (r2 = 0.011, p = 0.811). No difference occurred across age groups (Kruskal-Wallis, p = 0.157). Age had no association with diagnostic likelihood of choledocolithiasis (AOR [95% CI] 0.99 [0.98-1.01], adjusted-p = 0.335). Conclusion: In a large population undergoing investigation for biliary disease, increasing age was neither associated with increasing CBD diameter nor predictive of the likelihood of choledocolithiasis.