Matthew C. Hernandez

Increased anatomic severity predicts outcomes: Validation of the American Association for the Surgery of Trauma's Emergency General Surgery score in appendicitis

BACKGROUND Determination and reporting of disease severity in emergency general surgery lacks standardization. Recently, the American Association for the Surgery of Trauma (AAST) proposed an anatomic severity grading system. We aimed to validate this system in patients with appendicitis and determine if cross-sectional imaging correlates with disease severity at operation. METHODS Patients 18 years or older undergoing treatment for acute appendicitis between 2013 and 2015 were identified. Baseline demographics, procedure types were recorded, and AAST grades were assigned based on intraoperative and radiologic findings. Outcomes including length of stay, 30-day mortality, and complications based on Clavien-Dindo categories and National Surgical Quality Improvement Program variables. Summary statistical univariate, nominal logistic, and standard least squares analyses were performed comparing AAST grade with key outcomes. Bland-Altman analysis compared operative findings with preoperative cross-sectional imaging to compare assigning grades. RESULTS Three hundred thirty-four patients with mean (±SD) age of 39.3 years (±16.5) were included (53% men), and all patients had cross-sectional imaging. Two hundred ninety-nine underwent appendectomy, and 85% completed laparoscopic. Thirty-day mortality rate was 0.9%, complication rate was 21%. Increased (median [interquartile range, IQR]) AAST grade was recorded in patients with complications (2 [1–4]) compared with those without (1 [1–1], p = 0.001). For operative management, (median [IQR]) AAST grades were significantly associated with procedure type: laparoscopic (1 [1–1]), open (4 [2–5]), conversion to open (3 [1–4], p = 0.001). Increased (median [IQR]) AAST grades were significantly associated in nonoperative management: patients having a complication had a higher median AAST grade (4 [3–5]) compared with those without (3 [2–3], p = 0.001). Bland-Altman analysis comparing AAST grade and cross-sectional imaging demonstrated no difference (−0.02 ± 0.02; p = 0.2; coefficient of repeatability 0.9). CONCLUSIONS The AAST grading system is valid in our population. Increased AAST grade is associated with open procedures, complications, and length of stay. The AAST emergency general surgery grade determined by preoperative imaging strongly correlated to operative findings. LEVEL OF EVIDENCE Epidemiologic/prognostic study, level III.

Increased anatomic severity in appendicitis is associated with outcomes in a South African population.

BACKGROUND Severity of emergency general surgery (EGS) diseases has not been standardized until recently. The American Association for the Surgery of Trauma (AAST) proposed an anatomic severity grading system for EGS diseases to facilitate communication and quality comparisons between providers and hospitals. Previous work has demonstrated validity of the system for appendicitis in the United States. To demonstrate generalizability, we aim to externally validate this grading system in South African patients with appendicitis. METHODS Patients with acute appendicitis during 2010 to 2016 were identified at multi-institutional sites within South Africa. Baseline demographics and procedure types were recorded, and AAST grades were assigned based on intraoperative findings. Outcomes included duration of stay, mortality, and Clavien-Dindo complications. Summary statistical univariate and nominal logistic regression analyses were performed to compare AAST grade and outcomes. RESULTS A total of 1,415 patients with a median (interquartile range) age of 19 years (14–28 years) were included (55% men). One hundred percent underwent appendectomy: 63.5% completed via midline laparotomy, 36.5% via limited incision (31.8% via McBurney incision and 4.7% via laparoscopy). Overall, 30-day mortality rate was 1.4% with an overall complication rate of 44%. Most common complications included surgical site infection (n = 147, 10.4%), pneumonia (n = 105, 7.4%), and renal failure (n = 64, 4.5%). Distribution of AAST grade is as follows: Grade 0 (10, 0.7%), Grade 1 (247, 17.4%), Grade 2 (280, 19.8%), Grade 3 (158, 11.3%), Grade 4 (179, 12.6%), and Grade 5 (541, 38.2%). Increased median (interquartile range) AAST grades were recorded in patients with complications, 5 (3–5) compared with those without (2 [1–3], p = 0.001). Duration of stay was increased for patients with higher AAST grades: 4 and 5 (10.6 ± 5.9 days) versus I and II (3.6 ± 4.3 days; p = 0.001). Area under the receiver operating characteristic analysis to predict presence of any complication based on AAST grade was 0.90. CONCLUSION The AAST EGS grading system is valid to predict important clinical outcomes in a South African population with an increased degree of severity on presentation. These results support generalizability of the AAST EGS grading system for appendicitis in a developing nation. LEVEL OF EVIDENCE Prognostic, level II.

Platelet‐derived growth factor regulates YAP transcriptional activity via Src family kinase dependent tyrosine phosphorylation

The Hippo pathway effector YAP is implicated in the pathogenesis of cholangiocarcinoma (CCA). The Hippo pathway relies on signaling cross talk for its regulation. Given the importance of platelet derived growth factor receptor (PDGFR) signaling in CCA biology, our aim was to examine potential YAP regulation by PDGFR. We employed human and mouse CCA specimens and cell lines for these studies. Initially, we confirmed upregulation of PDGFRβ and PDGFR ligands in human and mouse CCA specimens and cell lines. YAP, a transcriptional co‐activator, was localized to the nucleus in human CCA specimens and a cell line, as well as patient derived xenografts (PDX). PDGFR pharmacologic inhibition led to a redistribution of YAP from the nucleus to cytosol and downregulation of YAP target genes in a human CCA cell line. siRNA silencing of PDGFR‐β similarly downregulated YAP target genes. YAP activation (nuclear localization and target gene expression) was regulated by Src family kinases (SFKs) downstream of PDGFR. SFK activity resulted in phosphorylation of YAP on tyrosine357 (YAPY357). The importance of YAPY357 phosphorylation in regulating YAP activation was confirmed utilizing the SB‐1 cell line, a mouse cell line expressing YAP S127A precluding canonical serine phosphorylation. PDGFR inhibition decreased cellular abundance of the survival protein Mcl‐1, a known YAP target gene, and accordingly increased cell death in CCA cells in vitro and in vivo. These preclinical data demonstrate that a PDGFR‐SFK cascade regulates YAP activation via tyrosine phosphorylation in CCA. Inhibiting this cascade may provide a viable therapeutic strategy for this human malignancy.

Visually guided tube thoracostomy insertion comparison to standard of care in a large animal model

INTRODUCTION Tube thoracostomy (TT) is a lifesaving procedure for a variety of thoracic pathologies. The most commonly utilized method for placement involves open dissection and blind insertion. Image guided placement is commonly utilized but is limited by an inability to see distal placement location. Unfortunately, TT is not without complications. We aim to demonstrate the feasibility of a disposable device to allow for visually directed TT placement compared to the standard of care in a large animal model. METHODS Three swine were sequentially orotracheally intubated and anesthetized. TT was conducted utilizing a novel visualization device, tube thoracostomy visual trocar (TTVT) and standard of care (open technique). Position of the TT in the chest cavity were recorded using direct thoracoscopic inspection and radiographic imaging with the operator blinded to results. Complications were evaluated using a validated complication grading system. Standard descriptive statistical analyses were performed. RESULTS Thirty TT were placed, 15 using TTVT technique, 15 using standard of care open technique. All of the TT placed using TTVT were without complication and in optimal position. Conversely, 27% of TT placed using standard of care open technique resulted in complications. Necropsy revealed no injury to intrathoracic organs. CONCLUSION Visual directed TT placement using TTVT is feasible and non-inferior to the standard of care in a large animal model. This improvement in instrumentation has the potential to greatly improve the safety of TT. Further study in humans is required. LEVEL OF EVIDENCE Therapeutic Level II.

Tube thoracostomy: Increased angle of insertion is associated with complications.

INTRODUCTION Tube thoracostomy (TT), considered a routine procedure, has significant complications. Current recommendations for placement rely on surface anatomy. There is no information to guide operators regarding angle of insertion relative to chest wall. We aim to determine if angle of insertion is associated with complications of TT. METHODS We performed a retrospective review of adult trauma patients who necessitated TT at a Level I trauma center over a 2-year period (January 2012 to December 2013). Tube thoracostomies performed intraoperatively or using radiological guidance were excluded. Thoracic anteroposterior or posteroanterior radiographs were reviewed to determine the angle of insertion of TT relative to the thoracic wall. A previously validated classification method was used to categorize complications. Descriptive and univariate statistics were used to compare angle of insertion and complicated versus uncomplicated TT. RESULTS Review identified 154 patients who underwent a total of 246 TT placed for emergent trauma. All patients had a postprocedural chest x-ray. We identified 90 complications (37%) over the study period. One hundred forty-four of the TTs reviewed had an angle of insertion less than 45 degrees of which there were 27 complications (19%). One hundred two of the TTs had an angle greater than 45 degrees and 63 complications (62%); p < 0.0001. CONCLUSIONS Tube thoracostomy insertion is inherently dangerous. Placement of TT using a higher angle of insertion greater than 45 degrees is associated with increased complications. Further prospective studies quantifying TT angle of insertion on outcomes are needed. LEVEL OF EVIDENCE Therapeutic study, level IV.

Definitive airway management after pre-hospital supraglottic airway insertion: Outcomes and a management algorithm for trauma patients

Background: Prehospital airway management increasingly involves supraglottic airway insertion and a paucity of data evaluates outcomes in trauma populations. We aim to describe definitive airway management in traumatically injured patients who necessitated prehospital supraglottic airway insertion. Methods: We performed a single institution retrospective review of multisystem injured patients (≥ 15 years) that received prehospital supraglottic airway insertion during 2009 to 2016. Baseline demographics, number and type of: supraglottic airway insertion attempts, definitive airway and complications were recorded. Primary outcome was need for tracheostomy. Univariate and multivariable statistics were performed. Results: 56 patients met inclusion criteria and were reviewed, 78% were male. Median age [IQR] was 36 [24–56] years. Injuries comprised blunt (94%), penetrating (4%) and burns (2%). Median ISS was 26 [22–41]. Median number of prehospital endotracheal intubation (PETI) attempts was 2 [1–3]. Definitive airway management included: (n = 20, 36%, tracheostomy), (n = 10, 18%, direct laryngoscopy), (n = 6, 11%, bougie), (n = 9, 15%, Glidescope), (n = 11, 20%, bronchoscopic assistance). 24‐hour mortality was 41%. Increasing number of PETI was associated with increasing facial injury. On regression, increasing cervical and facial injury patterns as well as number of PETI were associated with definitive airway control via surgical tracheostomy. Conclusions: After supraglottic airway insertion, operative or non‐operative approaches can be utilized to obtain a definitive airway. Patients with increased craniofacial injuries have an increased risk for airway complications and need for tracheostomy. We used these factors to generate an evidence based algorithm that requires prospective validation. Level of evidence: Level IV – Retrospective study. Study type: Retrospective single institution study.

Association of Post-operative Organ Space Infection After Intraoperative Irrigation in Appendicitis

BACKGROUND The benefit of intraoperative irrigation on postoperative abscess rates compared to suction alone is unclear. The American Association for the Surgery of Trauma grading system provides distinct disease severity stratification to determine if prior analyses were biased by anatomic severity. We hypothesized that for increasing appendicitis severity, patients receiving (high, ≥2 L) intraoperative irrigation would have increased postoperative organ space infection (OSI) rate compared to (low, <2 L) irrigation. METHODS Single-institution review of adults (>18 years) undergoing appendectomy for appendicitis during 2010-2016. Demographics, operative details, irrigation volumes, duration of stay, and complications (Clavien-Dindo classification) were collected. American Association for the Surgery of Trauma grades were assigned by two independent reviewers based on operative findings. Summary, univariate, and area under the receiver operating curve analyses were performed. RESULTS Patients (n = 1187) were identified with a mean (SD) age of 41.6 (18.4) years (45% female). Operative approach included laparoscopy (n = 1122 [94.5%]), McBurney incision (n = 10 [0.8%]), midline laparotomy (n = 16 [1.3 %]), and laparoscopy converted to laparotomy (n = 39 [3.4%)]. The mean (SD) volume of intraoperative irrigation was 410 (1200) mL. Complication rate was 26.1%. Median volume of intraoperative irrigation in patients who developed postoperative OSI was 3 [0–4] compared to 0 [0–0] in those without infection (p < 0.0001). Area under the receiver operating curve analysis determined that 2 or more liters of irrigation was associated with postoperative OSI (c statistic: 0.83, 95% confidence interval, 0.76–0.89; p < 0.001). CONCLUSION Irrigation is used for increasingly severe appendicitis with wide variation. Irrigation volumes of 2 L or greater are associated with postoperative OSI. Improving standardization of irrigation volume (<2 L) may prevent morbidity associated with this high-volume disease. LEVEL OF EVIDENCE Therapeutic, level IV.

The American Association for the Surgery of Trauma Severity Grade is valid and generalizable in adhesive small bowel obstruction

BACKGROUND The American Association for the Surgery of Trauma (AAST) anatomic severity grading system for adhesive small bowel obstruction (ASBO) was validated at a single institution. We aimed to externally validate the AAST ASBO grading system using the Eastern Association for the Surgery of Trauma multi-institutional small bowel obstruction prospective observational study. METHODS Adults (age ≥ 18) with (ASBO) were included. Baseline demographics, physiologic parameters (heart rate, blood pressure, respiratory rate), laboratory tests (lactate, hemoglobin, creatinine, leukocytosis), imaging findings, operative details, length of stay, and Clavien-Dindo complications were collected. The AAST ASBO grades were assigned by two independent reviewers based on imaging findings. Kappa statistic, univariate, and multivariable analyses were performed. RESULTS There were 635 patients with a mean (±SD) age of 61 ± 17.8 years, 51% female, and mean body mass index was 27.5 ± 8.1. The AAST ASBO grades were: grade I (n = 386, 60.5%), grade II (n = 135, 21.2%), grade III (n = 59, 9.2%), grade IV (n = 55, 8.6%). Initial management included: nonoperative (n = 385; 61%), laparotomy (n = 200, 31.3%), laparoscopy (n = 13, 2.0%), and laparoscopy converted to laparotomy (n = 37, 5.8%). An increased median [IQR] AAST ASBO grade was associated with need for conversion to an open procedure (2 [1–3] vs. 3 [2–4], p = 0.008), small bowel resection (2 [2–2] vs. 3 [2–4], p < 0.0001), postoperative temporary abdominal closure (2 [2–3] vs. 3 [3–4], p < 0.0001), and stoma creation (2 [2–3] vs. 3 [2–4], p < 0.0001). Increasing AAST grade was associated with increased anatomic severity noted on imaging findings, longer duration of stay, need for intensive care, increased rate of complication, and higher Clavien-Dindo complication grade. CONCLUSION The AAST ASBO severity grading system has predictive validity for important clinical outcomes and allows for standardization across institutions, providers, and future research focused on optimizing preoperative diagnosis and management algorithms. LEVEL OF EVIDENCE Prognostic, level III.

Perioperative Use of Nonsteroidal Anti-Inflammatory Drugs and the Risk of Anastomotic Failure in Emergency General Surgery

BACKGROUND Nonsteroidal anti-inflammatory drugs (NSAIDs) are commonly used analgesic and anti-inflammatory adjuncts. Nonsteroidal anti-inflammatory drug administration may potentially increase the risk of postoperative gastrointestinal anastomotic failure (AF). We aim to determine if perioperative NSAID utilization influences gastrointestinal AF in emergency general surgery (EGS) patients undergoing gastrointestinal resection and anastomosis. METHODS Post hoc analysis of a multi-institutional prospectively collected database was performed. Anastomotic failure was defined as the occurrence of a dehiscence/leak, fistula, or abscess. Patients using NSAIDs were compared with those without. Summary, univariate, and multivariable analyses were performed. RESULTS Five hundred thirty-three patients met inclusion criteria with a mean (±SD) age of 60 ± 17.5 years, 53% men. Forty-six percent (n = 244) of the patients were using perioperative NSAIDs. Gastrointestinal AF rate between NSAID and no NSAID was 13.9% versus 10.7% (p = 0.26). No differences existed between groups with respect to perioperative steroid use (16.8% vs. 13.8%; p = 0.34) or mortality (7.39% vs. 6.92%, p = 0.84). Multivariable analysis demonstrated that perioperative corticosteroid (odds ratio, 2.28; 95% confidence interval, 1.04–4.81) use and the presence of a colocolonic or colorectal anastomoses were independently associated with AF. A subset analysis of the NSAIDs cohort demonstrated an increased AF rate in colocolonic or colorectal anastomosis compared with enteroenteric or enterocolonic anastomoses (30.0% vs. 13.0%; p = 0.03). CONCLUSION Perioperative NSAID utilization appears to be safe in EGS patients undergoing small-bowel resection and anastomosis. Nonsteroidal anti-inflammatory drug administration should be used cautiously in EGS patients with colon or rectal anastomoses. Future randomized trials should validate the effects of perioperative NSAIDs use on AF. LEVEL OF EVIDENCE Therapeutic study, level III.BACKGROUND Nonsteroidal anti-inflammatory drugs (NSAIDs) are commonly used analgesic and anti-inflammatory adjuncts. NSAID administration may potentially increase the risk of postoperative gastrointestinal anastomotic failure (AF). We aim to determine if perioperative NSAID utilization influences gastrointestinal anastomotic failure in emergency general surgery (EGS) patients undergoing gastrointestinal resection and anastomosis. METHODS Post hoc analysis of a multi-institutional prospectively collected database was performed. Anastomotic failure was defined as the occurrence of a dehiscence/leak, fistula or abscess. Patients utilizing NSAIDS were compared to those without. Summary, univariate and multivariable analyses were performed. RESULTS 533 patients met inclusion criteria with a mean (±SD) age of 60 ±17.5years, 53% male. There were 46% (n=244) patients utilizing perioperative NSAIDs. Gastrointestinal anastomotic failure (AF) rate between NSAID and no NSAID was (13.9% vs 10.7%, p=0.26). No differences existed between groups with respect to perioperative steroid use (16.8% vs 13.8%, p=0.34), or mortality (7.39 vs 6.92%, p=0.84). Multivariable analysis demonstrated that perioperative corticosteroid (OR 2.28, CI 1.04-4.81) use and the presence of a colocolonic or colorectal anastomoses were independently associated with anastomotic failure. A subset analysis of the NSAIDs cohort demonstrated an increased AF rate in colocolonic or colorectal anastomosis compared to enteroenteric or enterocolonic anastomoses (30.0% vs 13.0%, p=0.03). CONCLUSION Perioperative NSAID utilization appears to be safe in emergency general surgery patients undergoing small bowel resection and anastomosis. NSAIDs administration should be used cautiously in EGS patients with colon or rectal anastomoses. Future randomized trials should validate the effects of perioperative NSAIDs use on AF. LEVEL OF EVIDENCE Therapeutic study, level III.

Injury patterns and outcomes of ice-fishing in the United States☆

INTRODUCTION Fishing is a common pastime. In the developed world, it is commonly performed as a recreational activity. We aim to determine injury patterns and outcomes among patients injured while ice fishing. METHODS Data on initial emergency department visits from the National Electronic Injury Surveillance System-All Injury Program (NEISS-AIP) from 2009-2014 were analyzed. All patients with fishing related injuries were included. Primary endpoint was rate of admission or transfer. Secondary endpoints were defined a priori anatomical injury categories and patients were assigned into groups. Descriptive and power analysis was performed between patients with ice-fishing and traditional fishing related injuries. RESULTS We identified 8220 patients who sustained fishing related injuries, of which n=85 (1%) involved ice fishing. Ice fishing injuries occurred primarily in males (88%) with a mean age of 39.4years ±17.5 (std dev). The most common injuries related to ice fishing were: orthopedic/musculoskeletal (46%), minor trauma (37%), and major trauma (6%). Hot thermal injuries (burns) were the fourth most common type of ice-fishing injury (5%) but rarely occurred in warmer fishing months (<1%, P=.004). Cold thermal injuries (1%) and hypothermia (0%) were rare among ice-fishing injuries and immersion/drowning occurred in 5% of cases. The rate of admission/transfer was significantly greater in ice-fishing (11%) than the traditional fishing patients 3%, (P<.001), power was 90%. CONCLUSION Ice fishing is associated with more severe injury patterns and more thermal injuries and immersion injuries than traditional fishing. Providers and participants should be aware of the potential risks and benefits and counseled appropriately.