It is Time to Replace Large Drains with Small Ones After Fixation of Rib Fractures: A Prospective Observational Study.

INTRODUCTION: Large-bore chest tubes are usually applied after thoracic surgery. Recently, small-bore tubes have been increasingly considered owing to the extensive use of video-assisted thoracoscopic surgery (VATS). This study assessed the differences in outcomes between large-bore and small-caliber drainage tubes in patients undergoing surgical stabilization of rib fractures (SSRF) with VATS. METHODS: Overall, 131 patients undergoing SSRF with VATS were prospectively enrolled, including 65 patients receiving 32-Fr chest tubes (group 1) and 66 patients receiving 14-Fr pigtail catheters (group 2) for postoperative drainage. The clinical characteristics and perioperative outcomes of the patients were compared. RESULTS: All patients underwent SSRF with VATS within 4 days after trauma. After the operation, the mean duration of chest tubes was longer than that of pigtail catheters, with statistical significance (5.08 ± 2.47 vs 3.11 ± 1.31, P = 0.001). Length of stay (LOS) was also longer in group 1 (10.38 ± 2.90 vs 8.18 ± 2.44, P = 0.001). After multivariate logistic regression, the only independent factors between the two groups were duration of postoperative drainage (adjusted odds ratio [AOR] 1.746; 95% confidence interval [CI] 0.171-10.583, P = 0.001) and hospital LOS (AOR 1.272; 95% CI 0.109-4.888, P = 0.027). CONCLUSION: After reconstruction of the chest wall and lung parenchyma, small-caliber drainage catheters could be easily and safely applied to reduce hospital LOS.

Machine Learning Models of Survival Prediction in Trauma Patients.

BACKGROUND: We aimed to build a model using machine learning for the prediction of survival in trauma patients and compared these model predictions to those predicted by the most commonly used algorithm, the Trauma and Injury Severity Score (TRISS). METHODS: Enrolled hospitalized trauma patients from 2009 to 2016 were divided into a training dataset (70% of the original data set) for generation of a plausible model under supervised classification, and a test dataset (30% of the original data set) to test the performance of the model. The training and test datasets comprised 13,208 (12,871 survival and 337 mortality) and 5603 (5473 survival and 130 mortality) patients, respectively. With the provision of additional information such as pre-existing comorbidity status or laboratory data, logistic regression (LR), support vector machine (SVM), and neural network (NN) (with the Stuttgart Neural Network Simulator (RSNNS)) were used to build models of survival prediction and compared to the predictive performance of TRISS. Predictive performance was evaluated by accuracy, sensitivity, and specificity, as well as by area under the curve (AUC) measures of receiver operating characteristic curves. RESULTS: In the validation dataset, NN and the TRISS presented the highest score (82.0%) for balanced accuracy, followed by SVM (75.2%) and LR (71.8%) models. In the test dataset, NN had the highest balanced accuracy (75.1%), followed by the TRISS (70.2%), SVM (70.6%), and LR (68.9%) models. All four models (LR, SVM, NN, and TRISS) exhibited a high accuracy of more than 97.5% and a sensitivity of more than 98.6%. However, NN exhibited the highest specificity (51.5%), followed by the TRISS (41.5%), SVM (40.8%), and LR (38.5%) models. CONCLUSIONS: These four models (LR, SVM, NN, and TRISS) exhibited a similar high accuracy and sensitivity in predicting the survival of the trauma patients. In the test dataset, the NN model had the highest balanced accuracy and predictive specificity.

Metagenome Analysis as a Tool to Study Bacterial Infection Associated with Acute Surgical Abdomen.

BACKGROUND: The purpose of this study was to profile the bacterium in the ascites and blood of patients with acute surgical abdomen by metagenome analysis. METHODS: A total of 97 patients with acute surgical abdomen were included in this study. Accompanied with the standard culture procedures, ascites and blood samples were collected for metagenome analysis to measure the relative abundance of bacteria among groups of patients and between blood and ascites. RESULTS: Metagenomic analysis identified 107 bacterial taxa from the ascites of patients. A principal component analysis (PCA) could separate the bacteria of ascites into roughly three groups: peptic ulcer, perforated or non-perforated appendicitis, and a group which included cholecystitis, small bowel lesion, and colon perforation. Significant correlation between the bacteria of blood and ascites was found in nine bacterial taxa both in blood and ascites with more than 500 sequence reads. However, the PCA failed to separate the variation in the bacteria of blood into different groups of patients, and the bacteria of metagenomic analysis is only partly in accordance with those isolated from a conventional culture method. CONCLUSION: This study indicated that the metagenome analysis can provide limited information regarding the bacteria in the ascites and blood of patients with acute surgical abdomen.

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.

Characteristics and Outcomes of Patients Injured in Road Traffic Crashes and Transported by Emergency Medical Services.

To investigate the injury characteristics and mortality of patients transported by emergency medical services (EMS) and hospitalized for trauma following a road traffic crash, data obtained from the Trauma Registry System were retrospectively reviewed for trauma admissions between 1 January 2009 and 31 December 2013 in a Level I trauma center. Of 16,548 registered patients, 3978 and 1440 patients injured in road traffic crashes were transported to the emergency department by EMS and non-EMS, respectively. Patients transported by EMS had lower Glasgow coma scale (GCS) scores and worse hemodynamic measures. Compared to patients transported by non-EMS, more patients transported by EMS required procedures (intubation, chest tube insertion, and blood transfusion) at the emergency department. They also sustained a higher injury severity, as measured by the injury severity score (ISS) and the new injury severity score (NISS). Lastly, in-hospital mortality was higher among the EMS than the non-EMS group (1.8% vs. 0.3%, respectively; p < 0.001). However, we found no statistically significant difference in the adjusted odds ratio (AOR) for mortality among patients transported by EMS after adjustment for ISS (AOR 4.9, 95% CI 0.33-2.26), indicating that the higher incidence of mortality was likely attributed to the patients' higher injury severity. In addition, after propensity score matching, logistic regression of 58 well-matched pairs did not show a significant influence of transportation by EMS on mortality (OR: 0.578, 95% CI: 0.132-2.541 p = 0.468).

Use of the reverse shock index for identifying high-risk patients in a five-level triage system.

BACKGROUND: The ratio of systolic blood pressure (SBP) to heart rate (HR), called the reverse shock index (RSI), is used to evaluate the hemodynamic stability of trauma patients. To minimize undertriage in emergency departments (EDs), we evaluated whether RSI < 1 (i.e., SBP lower than HR) could be used as an additional variable to identify patients at high risk for more severe injury within a level category of the five-level Taiwan Triage and Acuity Scales (TTAS) system. METHODS: Data obtained from the Trauma Registry System, including triage level according to the TTAS system, were retrospectively reviewed for trauma admissions from January 2009 through December 2013 in a Level I trauma center. In our study, the primary outcomes were injury severity as measured using different scoring systems, including the Glasgow coma scale (GCS), abbreviated injury scale scores, and the injury severity score (ISS), and in-hospital mortality. The secondary outcomes were hospital and intensive care unit (ICU) length of stay (LOS). RESULTS: Of 10,814 trauma patients, 348 patients (3.2%) had RSI < 1, whereas 10,466 (96.8%) had RSI ≥ 1. Those with RSI < 1 had greater injury severity, a higher incidence of commonly associated injuries, lower GCS scores, greater deterioration of vital signs, and a higher incidence of procedures those with RSI ≥ 1. Patients with RSI < 1 also worse outcomes including hospital and ICU LOS, a greater frequency of ICU admission, and higher in-hospital mortality. Although the five-level TTAS system provides good prioritization of patients with major trauma, using the additional criterion of RSI < 1 could identify the patients at higher risk within the same triage level (I-III). DISCUSSION: The alert of a trauma patient's SBP being lower than his/her HR (RSI < 1) without the requirement of any additional equipment makes the concept of RSI particularly valuable in crowded EDs for identifying high-risk patients. RSI < 1 may serve as a principle trigger for action in the ED to alert trauma surgeons to the need for early intervention and timely preparation upon patient arrival particularly for those patients triaged in levels II and III of the TTAS system. CONCLUSIONS: RSI < 1 upon arrival at an ED is an alarming sign of an associated worse outcome. Within the same triage level from level I to level III, patients with RSI < 1 had worse outcomes than those with RSI ≥ 1. The inclusion of RSI in the TTAS system may help to identify patients with more serious injuries who need an upgraded management level.

Obese patients who fall have less injury severity but a longer hospital stay than normal-weight patients.

BACKGROUND: The effects of obesity on injury severity and outcome have been studied in trauma patients but not in those who have experienced a fall. The aim of this study was to compare injury patterns, injury severities, mortality rates, and in-hospital or intensive care unit (ICU) length of stay (LOS) between obese and normal-weight patients following a fall. METHODS: Detailed data were retrieved for 273 fall-related hospitalized obese adult patients with a body mass index (BMI) ≥30 kg/m(2) and 2357 normal-weight patients with a BMI <25 kg/m(2) but ≥18.5 kg/m(2) from the Trauma Registry System of a Level I trauma center between January 1, 2009, and December 31, 2013. We used the Pearson's chi-squared test, Fisher's exact test, the Mann Whitney U test, and independent Student's t-test to analyze differences between the two groups. RESULTS: Analysis of AIS scores and AIS severity scaling from 1 to 5 revealed no significant differences in trauma regions between obese and normal-weight patients. When stratified by injury severity (Injury Severity Score [ISS] of <16, 16-24, or ≥25), more obese patients had an ISS of <16 compared to normal-weight patients (90.5 % vs. 86.0 %, respectively; p = 0.041), while more normal-weight patients had an ISS between 16 and 24 (11.0 % vs. 6.6 %, respectively; p = 0.025). Obese patients who had experienced a fall had a significantly lower ISS (median (range): 9 (1-45) vs. 9 (1-50), respectively; p = 0.015) but longer in-hospital LOS than did normal-weight patients (10.1 days vs. 8.9 days, respectively; p = 0.049). Even after taking account of possible differences in comorbidity and ISS, the obese patients have an average 1.54 day longer LOS than that of normal-weight patients. However, no significant differences were found between obese and normal-weight patients in terms of the New Injury Severity Score (NISS), Trauma-Injury Severity Score (TRISS), mortality, percentage of patients admitted to the ICU, or LOS in the ICU. CONCLUSION: Obese patients who had experienced a fall did not have different injured body regions than did normal-weight patients. However, they had a lower ISS but a longer in-hospital LOS than did normal-weight patients.

Predictors of the development of post-snakebite compartment syndrome.

BACKGROUND: To identify the factors associated with the development of post-snakebite compartment syndrome (PSCS) in snakebite patients and to analyze the clinical prognosis of these patients. METHODS: We retrospectively reviewed the medical records of patients who presented to our institution with snakebites from March 2009 to December 2012. The clinical data, hospital course and outcome were all recorded. RESULTS: A total of 136 patients were included in the present study. Nine patients developed PSCS and underwent fasciotomy. Relative to the non-PSCS group, the PSCS group demonstrated a significant increase in the white blood cell count (WBC, p = 0.006), segment form (Seg, p ≤ 0.001), aspartate aminotransferase level (AST, p = 0.002) and alanine aminotransferase level (ALT, p = 0.008). Elevated WBC count and AST level were identified as independent risk factors for PSCS (p = 0.028 and 0.037, respectively) in a multivariate analysis. CONCLUSIONS: Snakebite patients have a high likelihood of developing locoregional complications such as PSCS. Symptomatic snakebite patients should be observed for at least 48 h, and increased WBC counts and AST levels are risk factors for PSCS.

Extended central hepatectomy with preservation of segment 6 for patients with centrally located hepatocellular carcinoma.

BACKGROUND: In order to preserve functional liver parenchyma, extended central hepatectomy (segments 4, 5, 7 and 8 resection) was proposed for the management of centrally located hepatocellular carcinoma invading the right and middle hepatic veins, reconstructing segment 6 outflow in the absence of the thick inferior right hepatic vein. The present study was to describe our surgical techniques of extended central hepatectomy. METHODS: Between 2008 and 2012, 5 patients with centrally located hepatocellular carcinoma invading or in the vicinity of the right and middle hepatic veins underwent extended central hepatectomy. The thick inferior right hepatic vein was preserved during dissection. Gore-Tex graft was used for segment 6 outflow reconstruction in the absence of the thick inferior right hepatic vein. RESULTS: The mean future remnant liver volume for segments 2 and 3 was 28% versus 45% on segment 6 preservation. The mean tumor diameter was 7.4 cm. The thick inferior right hepatic vein was found in 1 patient. Outflow reconstruction from segment 6 was performed in 4 patients. Postoperative complications included bile leakage (1 patient), pleural effusion (2) and liver failure (1). The rate of graft patency was 75%. There was no perioperative mortality. CONCLUSION: Extended central hepatectomy is a safe alternative for extended hepatic resection in selected patients attempting to preserve the functional liver parenchyma.