Removal of the Prehospital Tourniquet in the Emergency Department.

BACKGROUND: Life-threatening hemorrhage from extremity injuries can be effectively controlled in the prehospital environment through direct pressure, wound packing, and the use of tourniquets. Early tourniquet application has been prioritized for rapid control of severe extremity hemorrhage and is a cornerstone of prehospital trauma resuscitation guidelines. Emergency physicians must be knowledgeable regarding the initial assessment and appropriate management of patients who present with a prehospital tourniquet in place. DISCUSSION: An interdisciplinary group of experts including emergency physicians, trauma surgeons, and tactical and Emergency Medical Services physicians collaborated to develop a stepwise approach to the assessment and removal (discontinuation) of an extremity tourniquet in the emergency department after being placed in the prehospital setting. We have developed a best-practices guideline to serve as a resource to aid the emergency physician in how to safely remove a tourniquet. The guideline contains five steps that include: 1) Determine how long the tourniquet has been in place; 2) Evaluate for contraindications to tourniquet removal; 3) Prepare for tourniquet removal; 4) Release the tourniquet; and 5) Monitor and reassess the patient. CONCLUSION: These steps outlined will help emergency medicine clinicians appropriately evaluate and manage patients presenting with tourniquets in place. Tourniquet removal should be performed in a systematic manner with plans in place to immediately address complications.

Discontinuity of the Bowel Following Damage Control Operation Revisited: A Multi-institutional Study.

BACKGROUND: Discontinuity of the bowel following intestinal injury and resection is a common practice in damage control procedures for severe abdominal trauma. However, there are concerns that complete occlusion of the bowel, especially in the presence of hypotension or edema that may result in ischemic bowel changes or increase bacterial or toxin translocation. METHODS: This was a retrospective study from three Level-1 trauma centers. Included were trauma patients who required bowel resection and damage control. The study population was stratified into two groups based on the management for bowel injury: bowel discontinuity versus primary anastomosis. Outcomes included anastomotic leak, organ space infection, bowel ischemia, and mortality. RESULTS: A total of 167 cases were included. In 84 cases, continuity of the bowel was established, and in 83, the bowel was left in discontinuity. The epidemiological, admission, and intraoperative physiological characteristics, the abdominal Abbreviated Injury Scale, type of intra-abdominal injury, and transfusion requirements were similar in the two study groups. The mortality was 8.3 % in the continuity group and 16.9 % for the discontinuity group (p = 0.096). On the crude bivariate and adjusted regression analyses, there was a higher rate of bowel ischemia at the take-back operation in the discontinuity group (p = 0.003 for the crude and p = 0.034 for the adjusted). The organ space infection and anastomotic leak rate were not significantly different between the study groups. CONCLUSIONS: Discontinuity of the bowel following damage control operation is associated with a higher risk of bowel ischemia than in patients with anastomosis. Further prospective observational and randomized studies are warranted. LEVEL OF EVIDENCE: III.

Cannabis Use Has Negligible Effects Following Severe Traumatic Injury.

Nearly half of all states have legalized medical marijuana or recreational-use marijuana. As more states move toward legalization, the effects on injured patients must be evaluated. This study sought to determine effects of cannabis positivity at the time of severe injury on hospital outcomes compared with individuals negative for illicit substances and those who were users of other illicit substances. A Level I trauma center performed a retrospective chart review covering subjects over a 2-year period with toxicology performed and an Injury Severity Score (ISS) of more than 16. These individuals were divided into the negative and positive toxicology groups, further divided into the marijuana-only, other drugs-only, and mixed-use groups. Differences in presenting characteristics, hospital length of stay, intensive care unit (ICU) stays, ventilator days, and death were compared. A total of 8,441 subjects presented during the study period; 2,134 (25%) of these had toxicology performed; 843 (40%) had an ISS of more than 16, with 347 having negative tests (NEG); 70 (8.3%) substance users tested positive only for marijuana (MO), 323 (38.3%) for other drugs-only, excluding marijuana (OD), and 103 (12.2%) subjects showed positivity for mixed-use (MU). The ISS was similar for all groups. No differences were identified in Glasgow Coma Scale (GCS), ventilator days, blood administration, or ICU/hospital length of stay when comparing the MO group with the NEG group. Significant differences occurred between the OD group and the NEG/MO/MU groups for GCS, ICU length of stay, and hospital charges. Cannabis users suffering from severe injury demonstrated no detrimental outcomes in this study compared with nondrug users.

Isolation, identification and characterization of Paenibacillus polymyxa CR1 with potentials for biopesticide, biofertilization, biomass degradation and biofuel production.

BACKGROUND: Paenibacillus polymyxa is a plant-growth promoting rhizobacterium that could be exploited as an environmentally friendlier alternative to chemical fertilizers and pesticides. Various strains have been isolated that can benefit agriculture through antimicrobial activity, nitrogen fixation, phosphate solubilization, plant hormone production, or lignocellulose degradation. However, no single strain has yet been identified in which all of these advantageous traits have been confirmed. RESULTS: P. polymyxa CR1 was isolated from degrading corn roots from southern Ontario, Canada. It was shown to possess in vitro antagonistic activities against the common plant pathogens Phytophthora sojae P6497 (oomycete), Rhizoctonia solani 1809 (basidiomycete fungus), Cylindrocarpon destructans 2062 (ascomycete fungus), Pseudomonas syringae DC3000 (bacterium), and Xanthomonas campestris 93-1 (bacterium), as well as Bacillus cereus (bacterium), an agent of food-borne illness. P. polymyxa CR1 enhanced growth of maize, potato, cucumber, Arabidopsis, and tomato plants; utilized atmospheric nitrogen and insoluble phosphorus; produced the phytohormone indole-3-acetic acid (IAA); and degraded and utilized the major components of lignocellulose (lignin, cellulose, and hemicellulose). CONCLUSIONS: P. polymyxa CR1 has multiple beneficial traits that are relevant to sustainable agriculture and the bio-economy. This strain could be developed for field application in order to control pathogens, promote plant growth, and degrade crop residues after harvest.

Comparative and genetic analysis of the four sequenced Paenibacillus polymyxa genomes reveals a diverse metabolism and conservation of genes relevant to plant-growth promotion and competitiveness.

BACKGROUND: Members of the genus Paenibacillus are important plant growth-promoting rhizobacteria that can serve as bio-reactors. Paenibacillus polymyxa promotes the growth of a variety of economically important crops. Our lab recently completed the genome sequence of Paenibacillus polymyxa CR1. As of January 2014, four P. polymyxa genomes have been completely sequenced but no comparative genomic analyses have been reported. RESULTS: Here we report the comparative and genetic analyses of four sequenced P. polymyxa genomes, which revealed a significantly conserved core genome. Complex metabolic pathways and regulatory networks were highly conserved and allow P. polymyxa to rapidly respond to dynamic environmental cues. Genes responsible for phytohormone synthesis, phosphate solubilization, iron acquisition, transcriptional regulation, σ-factors, stress responses, transporters and biomass degradation were well conserved, indicating an intimate association with plant hosts and the rhizosphere niche. In addition, genes responsible for antimicrobial resistance and non-ribosomal peptide/polyketide synthesis are present in both the core and accessory genome of each strain. Comparative analyses also reveal variations in the accessory genome, including large plasmids present in strains M1 and SC2. Furthermore, a considerable number of strain-specific genes and genomic islands are irregularly distributed throughout each genome. Although a variety of plant-growth promoting traits are encoded by all strains, only P. polymyxa CR1 encodes the unique nitrogen fixation cluster found in other Paenibacillus sp. CONCLUSIONS: Our study revealed that genomic loci relevant to host interaction and ecological fitness are highly conserved within the P. polymyxa genomes analysed, despite variations in the accessory genome. This work suggets that plant-growth promotion by P. polymyxa is mediated largely through phytohormone production, increased nutrient availability and bio-control mechanisms. This study provides an in-depth understanding of the genome architecture of this species, thus facilitating future genetic engineering and applications in agriculture, industry and medicine. Furthermore, this study highlights the current gap in our understanding of complex plant biomass metabolism in Gram-positive bacteria.

Diagnostic and therapeutic considerations in cases of civilian intravascular ballistic embolism: a review of case reports.

Background: Ballistic embolism (BE) is a rare complication of firearm injuries notoriously associated with a vexing clinical picture in the trauma bay. Unless considered early, the associated confusion can lead to needless delay in the management of the patient with a gunshot wound. Despite this known entity, there is a relative paucity of high-grade evidence regarding complications, management, and follow-up in these patients. Methods: An electronic database literature search was conducted to identify cases of acute intravascular BE in pediatric and adult civilians occurring during index hospitalization, filtered to publications during the past 10 years. Exclusion criteria included non-vascular embolization, injuries occurring in the military setting, and delayed migration defined as occurring after discharge from the index hospitalization. Results: A total of 136 cases were analyzed. Nearly all cases of BE occurred within 48 hours of presentation. Compared with venous emboli, arterial emboli were significantly more likely to be symptomatic (71% vs. 7%, p<0.001), and 43% of patients developed symptoms attributable to BE in the trauma bay. In addition, arterial emboli were significantly less likely to be managed non-invasively (19% vs. 49%, p<0.001). Open retrieval was significantly more likely to be successful compared with endovascular attempts (91% vs. 29%, p<0.001). Patients with arterial emboli were more likely to receive follow-up (52% vs. 39%) and any attempt at retrieval during the hospitalization was significantly associated with outpatient follow-up (p=0.034). All but one patient remained stable or had clinically improved symptoms after discharge. Conclusion: Consideration for BE is reasonable in any patient with new or persistent unexplained signs or symptoms, especially during the first 48 hours after a penetrating firearm injury. Although venous BE can often be safely observed, arterial BE generally necessitates urgent retrieval. Patients who are managed non-invasively may benefit from follow-up in the first year after injury.

Perspectives of surrogate decision makers for critically ill patients regarding gene variation research.

PURPOSE: We undertook this investigation to explore the manner in which surrogate decision makers for critically ill patients perceived genetic data collected in the context of clinical investigation. METHODS: Surrogate decision makers for critically ill patients cared for in intensive care units of two urban hospitals participated in focus groups designed to explore perceptions regarding gene variation research. RESULTS: Surrogate decision makers were generally familiar with genetic concepts and reported that they could provide an informed opinion regarding permitting (or declining) the participation of their loved ones in gene variation research. Respondents perceived the risk associated with this type of research largely as the risk associated with acquiring the sample (i.e., whether it involved an invasive procedure or not) but appreciated that genetic samples could provide information not readily obtained from nongenetic sources. Concerns about potential misuse of genetic data largely centered on misconduct, paternity, forensic applications, and insurance and employment discrimination. Although surrogate decision makers expressed that their loved ones would have interest in return of results and being recontacted for future use, these interests were secondary to confidentiality concerns. CONCLUSION: Respondents perceived genetic and nongenetic data as comparable. Informed consent processes that provide clear information regarding confidentiality protections, specimen handling, and parameters for future use may enhance enrollment.Genet Med 2013:15(5):368-373.

Ethical considerations in embedding a surgeon in a military or civilian tactical team.

Tactical emergency medical services (TEMS) bring immediate medical support to the inner perimeter of special weapons and tactics team activations. While initially envisioned as a role for an individual dually trained as a police officer and paramedic, TEMS is increasingly undertaken by physicians and paramedics who are not police officers. This report explores the ethical underpinnings of embedding a surgeon within a military or civilian tactical team with regard to identity, ethically acceptable actions, triage, responsibility set, training, certification, and potential future refinements of the role of the tactical police surgeon.

Year in review 2010: Critical Care--Cardiac arrest and cardiopulmonary resuscitation.

This review will summarize some of the data published in 2010 and focus on papers published in Critical Care in regard to cardiac arrest and cardiopulmonary resuscitation. In particular, we discuss the latest research in therapeutic hypothermia after cardiac arrest, including methods of inducing hypothermia, potential protective mechanisms, spontaneous hypothermia versus therapeutic hypothermia, and several predictors of outcome. Furthermore, we will discuss the effects of bystander-initiated cardiopulmonary resuscitation (CPR) in patients with physician-assisted advanced cardiac life support, the role of hypercapnea in near-death experiences during cardiac arrest, markers of endothelial injury and endothelial repair after CPR, and the prognostic value of cell-free plasma DNA as a marker of poor outcome after cardiac arrest.

Does temporary chest wall closure with or without chest packing improve survival for trauma patients in shock after emergent thoracotomy?

BACKGROUND: Many surgeons avoid the damage-control techniques of intrathoracic packing and temporary chest wall closure after thoracotomy for trauma because of concerns about packing's effects on intrathoracic pressure and infectious risks. We hypothesized that temporary chest closure with or without intrathoracic packing (TCC-P) as a method of thoracic damage control would yield higher than expected survival rates for trauma thoracotomy patients with metabolic exhaustion, whereas traditional definitive chest closure (DEF) would exhibit predicted survival rates. METHODS: This was a retrospective cohort study by two urban Level I trauma centers on patients who (1) underwent emergent thoracotomy for trauma, (2) received ≥10 units (U) packed red blood cells and/or sustained a cardiac arrest before starting chest closure, and (3) survived to intensive care unit arrival. Demographic/physiologic data, chest closure method, and thoracic complications were gathered. Trauma injury severity scores (TRISS) were used to calculate survival probability for TCC-P and DEF. Nonparametric statistics were used for all comparisons. All values are expressed as medians and interquartile ranges (IQR). RESULTS: Sixty-one patients met inclusion criteria. Both TCC-P (n = 17) and DEF (n = 44) were severely injured (ISS=35 [IQR, 25-42] vs. 29 [IQR 19-45] and packed red blood cells = 16.5 U [IQR, 12.3-25.5 U] vs. 15 U [IQR, 11-23 U], respectively; p=ns). Patient demographics were similar except for the findings that the TCC-P cohort had higher rates of cardiac arrest before starting chest closure (TCC-P 82% vs. DEF 48%, p=0.04), significantly more severe abdominal injuries, and less severe head injuries than the DEF group. No significant differences were observed in survival of the overall samples (TCC-P=47% vs. DEF=57%), nor for observed:expected (O:E) survival ratio in 13 patients with TCC-P and 30 with DEF meeting criteria for TRISS calculation (TCC-P O:E, 46%:39%; DEF O:E, 53%:57%). No significant differences were found for TCC-P and DEF thoracic infectious (24% vs. 25%) or hemorrhagic (18% vs. 14%) complications. Surprisingly, peak inspiratory pressures on intensive care unit arrival were markedly better after TCC-P (20 cm H2O [IQR, 18-31 cm H2O]) than after DEF (32.5 cm H2O [IQR, 28-37.5 cm H2O], p=0.003). CONCLUSION: Concerns about TCC-P are not borne out as thoracic infection rates are unaffected and peak pressures are actually lower, possibly due to greater pleural volume from an open chest wall and skin-only closure. However, no significant survival benefit was seen with TCC-P.

Early blood product and crystalloid volume resuscitation: risk association with multiple organ dysfunction after severe blunt traumatic injury.

BACKGROUND: Elements of volume resuscitation from hemorrhagic shock, such as amount of blood product and crystalloid administration, have been shown to be associated with multiple organ dysfunction (MOD). However, it is unknown whether these are causative factors or merely markers of an underlying requirement for large-volume resuscitation. We sought to further delineate the relevance of the major individual components of early volume resuscitation to onset of MOD after severe blunt traumatic injury. METHODS: We performed a secondary analysis of a large, multicenter prospective observational cohort of severely injured blunt trauma patients, the NIGMS Trauma Glue Grant, to assess the relevance of individual components of resuscitation administered in the first 12 hours of resuscitation including packed red blood cells (PRBC), fresh frozen plasma (FFP), and isotonic crystalloid, to the onset of MOD within the first 28 days after injury. Deaths within 48 hours of injury were excluded. We used a two tiered, exhaustive logistic regression model search technique to adjust for potential confounders from clinically relevant MOD covariates, including indicators of shock severity, injury severity, comorbidities, age, and gender. RESULTS: The study cohort consisted of 1,366 severely injured blunt trauma patients (median new Injury Severity Score = 34). Incidence of 28-day Marshall MOD was 19.6%. Transfusion of ≥10 Units of PRBC in the first 12 hours (odds ratio, 2.06; 95% confidence interval 1.44-2.94), but not FFP (≥8 U) or large volume crystalloid administration (≥12 L), was independently associated with onset of 28-day Marshall MOD. PRBC:FFP ratio in the first 12 hours was not significantly associated with MOD. CONCLUSIONS: When controlling for all major components of acute volume resuscitation, massive-transfusion volumes of PRBC's within the first 12 hours of resuscitation are modestly associated with MOD, whereas FFP and large volume crystalloid administration are not independently associated with MOD. Previous reported associations of blood products and large-volume crystalloid with MOD may be reflecting overall resuscitation requirements and burden of injury rather than independent causation.

PREVENTion of CLots in Orthopaedic Trauma (PREVENT CLOT): a randomised pragmatic trial protocol comparing aspirin versus low-molecular-weight heparin for blood clot prevention in orthopaedic trauma patients.

INTRODUCTION: Patients who sustain orthopaedic trauma are at an increased risk of venous thromboembolism (VTE), including fatal pulmonary embolism (PE). Current guidelines recommend low-molecular-weight heparin (LMWH) for VTE prophylaxis in orthopaedic trauma patients. However, emerging literature in total joint arthroplasty patients suggests the potential clinical benefits of VTE prophylaxis with aspirin. The primary aim of this trial is to compare aspirin with LMWH as a thromboprophylaxis in fracture patients. METHODS AND ANALYSIS: PREVENT CLOT is a multicentre, randomised, pragmatic trial that aims to enrol 12 200 adult patients admitted to 1 of 21 participating centres with an operative extremity fracture, or any pelvis or acetabular fracture. The primary outcome is all-cause mortality. We will evaluate non-inferiority by testing whether the intention-to-treat difference in the probability of dying within 90 days of randomisation between aspirin and LMWH is less than our non-inferiority margin of 0.75%. Secondary efficacy outcomes include cause-specific mortality, non-fatal PE and deep vein thrombosis. Safety outcomes include bleeding complications, wound complications and deep surgical site infections. ETHICS AND DISSEMINATION: The PREVENT CLOT trial has been approved by the ethics board at the coordinating centre (Johns Hopkins Bloomberg School of Public Health) and all participating sites. Recruitment began in April 2017 and will continue through 2021. As both study medications are currently in clinical use for VTE prophylaxis for orthopaedic trauma patients, the findings of this trial can be easily adopted into clinical practice. The results of this large, patient-centred pragmatic trial will help guide treatment choices to prevent VTE in fracture patients. TRIAL REGISTRATION NUMBER: NCT02984384.

A survey of critical care training amongst surgical residents: will they be ready?

BACKGROUND: Residents' duty-hour limitations and the trends towards closed-staffing for surgical critical care (SCC) have reshaped educational paradigms. No study has yet addressed the impact of these changes on resident SCC training. In our study, we investigated residents' experiences and perceptions of SCC education and practice. METHODS: At the end of the academic year 2007-2008, we distributed anonymous surveys to categorical general surgery residents in a large, university-based residency. All dedicated SCC rotations are currently completed by the end of PGY3. The survey measured residents' ratings of teaching, experiences, satisfaction, and self-assessed comfort with common SCC diseases and procedures. RESULTS: The response rate was 78% (n = 52/67). At the time of the survey, the 52 respondents had completed 9.3 +/- 4.5 wk of SCC rotations. Despite no rotations beyond PGY3, senior residents (PGYs 4/5) reported significantly greater SCC training time (13.1 versus 7.8 wk) and comfort managing SCC diseases and procedures than juniors (PGY 3). Attendings were rated the most effective didactic teachers, and senior residents the most effective procedural teachers. The mean education satisfaction score was 3.9 +/- 0.9 (5 = extremely satisfied). Residents anticipated performing minimal SCC management of their own patients, but most felt that SCC-trained surgeons should manage critically ill surgery patients. Seniors reported greater SCC fellowship interest (19% versus 0%). The addition of acute care surgery increased interest in 30% of respondents. CONCLUSIONS: Senior residents reported greater comfort with SCC management despite the lack of senior SCC rotations, whilst dedicated training time for junior residents appears to be declining. Residents wish subspecialist care for their critically ill patients, but the low interest in SCC fellowships suggests future physician shortages in this subspecialty.

Year in review 2009: Critical Care--cardiac arrest, trauma and disasters.

During 2009, Critical Care published nine papers on various aspects of resuscitation, prehospital medicine, trauma care and disaster response. One article demonstrated that children as young as 9 years of age can learn cardiopulmonary resuscitation (CPR) effectively, although, depending on their size, some may have difficulty performing it. Another paper showed that while there was a trend toward mild therapeutic hypothermia reducing S-100 levels, there was no statistically significant change. Another predictor study also showed a strong link between acute kidney injury and neurologic outcome while another article described a program in which kidneys were harvested from cardiac arrest patients and showed an 89% graft survival rate. One experimental investigation indicated that when a pump-less interventional lung assist device is present, leaving the device open (unclamped) while performing CPR has no harmful effects on mean arterial pressures and it may have positive effects on blood oxygenation and CO2 clearance. One other study, conducted in the prehospital environment, found that end-tidal CO2 could be useful in diagnosing pulmonary embolism. Three articles addressed disaster medicine, the first of which described a triage system for use during pandemic influenza that demonstrated high reliability in delineating patients with a good chance of survival from those likely to die. The other two studies, both drawn from the 2008 Sichuan earthquake experience, showed success in treating crush injured patients in an on-site tent ICU and, in the second case, how the epidemiology of earthquake injuries and related factors predicted mortality.

Year in review 2008: Critical Care--trauma.

Eleven papers on trauma published in Critical Care during 2008 addressed traumatic brain injury (TBI), burns, diagnostic concerns and immunosuppression. In regard to TBI, preliminary results indicate the utility of either magnetic resonance imaging (MRI) or ultrasound in measuring optic nerve sheath diameter to identify elevated intracranial pressure (ICP) as well as the potential benefit of thiopental for refractory ICP. Another investigation demonstrated that early extubation of TBI patients whose Glasgow Coma Scale score was 8 or less did not result in additional incidence of nosocomial pneumonia. Another study indicated that strict glucose control resulted in worse outcomes during the first week after TBI, but improved outcomes after the second week. Another paper showed the prolonged neuroprotective advantages of progesterone administration in TBI patients. There was also guidance on improved classifications of renal complications in burn patients. Another study found that patients with inhalation injuries and increased interleukin-6 (IL-6) and IL-10 and decreased IL-7 had increased mortality rates. One literature review described the disadvantages of prolonged immobilization or additional use of MRI for ruling out cervical spine injuries in obtunded TBI patients already cleared by computerized tomography scans. Other investigators found that higher N-terminal pro B-type natriuretic peptide (NT-proBNP) levels may be useful markers for post-traumatic cardiac impairment. Finally, an experimental model showed that both splenic apoptosis and lymphocytopenia may occur shortly after severe hemorrhage, thus increasing the threat of immunosuppression in those with severe blood loss.

The lifesaving potential of specialized on-scene medical support for urban tactical operations.

Since the 1980s, the specialized field of tactical medicine has evolved with growing support from numerous law-enforcement and medical organizations. On-scene backup from tactical emergency medical support (TEMS) providers has not only permitted more immediate advanced medical aid to injured officers, victims, bystanders, and suspects, but also allows for rapid after-incident medical screening or minor treatments that can obviate an unnecessary transport to an emergency department. The purpose of this report is to document one very explicit benefit of TEMS deployment, namely, a situation in which a police officer's life was saved by the routine on-scene presence of specialized TEMS physicians. In this specific case, a police officer was shot in the anterior neck during a law-enforcement operation and became moribund with massive hemorrhage and compromised airway. Two TEMS physicians, who had been integrated into the tactical law-enforcement team, were on scene, controlled the hemorrhage, and provided a surgical airway. By the time of arrival at the hospital, the patient had begun purposeful movements and, within 12 hours, was alert and oriented. Considering the rapid decline in the patient's condition, it was later deemed by quality assurance reviewers that the on-scene presence of these TEMS providers was lifesaving.