Association of initial lactate levels and red blood cell transfusion strategy with outcomes after severe trauma: a post hoc analysis of the RESTRIC trial.

BACKGROUND: The appropriateness of a restrictive transfusion strategy for those with active bleeding after traumatic injury remains uncertain. Given the association between tissue hypoxia and lactate levels, we hypothesized that the optimal transfusion strategy may differ based on lactate levels. This post hoc analysis of the RESTRIC trial sought to investigate the association between transfusion strategies and patient outcomes based on initial lactate levels. METHODS: We performed a post hoc analysis of the RESTRIC trial, a cluster-randomized, crossover, non-inferiority multicenter trials, comparing a restrictive and liberal red blood cell transfusion strategy for adult trauma patients at risk of major bleeding. This was conducted during the initial phase of trauma resuscitation; from emergency department arrival up to 7 days after hospital admission or intensive care unit (ICU) discharge. Patients were grouped by lactate levels at emergency department arrival: low (< 2.5 mmol/L), middle (≥ 2.5 and < 4.0 mmol/L), and high (≥ 4.0 mmol/L). We compared 28 days mortality and ICU-free and ventilator-free days using multiple linear regression among groups. RESULTS: Of the 422 RESTRIC trial participants, 396 were analyzed, with low (n = 131), middle (n = 113), and high (n = 152) lactate. Across all lactate groups, 28 days mortality was similar between strategies. However, in the low lactate group, the restrictive approach correlated with more ICU-free (ß coefficient 3.16; 95% CI 0.45 to 5.86) and ventilator-free days (ß coefficient 2.72; 95% CI 0.18 to 5.26) compared to the liberal strategy. These findings persisted even after excluding patients with severe traumatic brain injury. CONCLUSIONS: Our results suggest that restrictive transfusion strategy might not have a significant impact on 28-day survival rates, regardless of lactate levels. However, the liberal transfusion strategy may lead to shorter ICU- and ventilator-free days for patients with low initial blood lactate levels.

Clinical parameter-guided initial resuscitation in adult patients with septic shock: A systematic review and network meta-analysis.

Aim: To identify the most useful tissue perfusion parameter for initial resuscitation in sepsis/septic shock adults using a network meta-analysis. Methods: We searched major databases until December 2022 for randomized trials comparing four tissue perfusion parameters or against usual care. The primary outcome was short-term mortality up to 90 days. The Confidence in Network Meta-Analysis web application was used to assess the quality of evidence. Results: Seventeen trials were identified. Lactate-guided therapy (risk ratios, 0.59; 95% confidence intervals [0.45-0.76]; high certainty) and capillary refill time-guided therapy (risk ratios, 0.53; 95% confidence intervals [0.33-0.86]; high certainty) were significantly associated with lower short-term mortality compared with usual care, whereas central venous oxygen saturation-guided therapy (risk ratio, 1.50; 95% confidence intervals [1.16-1.94]; moderate certainty) increased the risk of short-term mortality compared with lactate-guided therapy. Conclusions: Lactate or capillary refill time-guided initial resuscitation for sepsis/septic shock patients may decrease short-term mortality. More research is essential to personalize and optimize treatment strategies for septic shock resuscitation.

Effect of stomach inflation during cardiopulmonary resuscitation on return of spontaneous circulation in out-of-hospital cardiac arrest patients: A retrospective observational study.

BACKGROUND: Gastric inflation caused by excessive ventilation is a common complication of cardiopulmonary resuscitation. Gastric inflation may further compromise ventilation via increases in intrathoracic pressure, leading to decreased venous return and cardiac output, which may impair out-of-hospital cardiac arrest (OHCA) outcomes. The purpose of this study was to measure the gastric volume of OHCA patients using computed tomography (CT) scan images and evaluate the effect of gastric inflation on return of spontaneous circulation (ROSC). METHODS: In this single-center, retrospective, observational study, CT scan was conducted after ROSC or immediately after death. Total gastric volume was measured. Primary outcome was ROSC. Achievement of ROSC was compared in the gastric distention group and the no gastric distention group; gastric distension was defined as total gastric volume in the ≥75th percentile. Additionally, factors associated with gastric distention were examined. RESULTS: A total of 446 cases were enrolled in the study; 120 cases (27%) achieved ROSC. The median gastric volume was 400 ml for all OHCA subjects; 1068 ml in gastric distention group vs. 287 ml in no gastric distention group. There was no difference in ROSC between the groups (27/112 [24.1%] vs. 93/334 [27.8%], p = 0.440). Gastric distention did not have a significant impact, even after adjustments (adjusted odds ratio 0.73, 95% confidence interval [0.42-1.29]). Increased gastric volume was associated with longer emergency medical service activity time. CONCLUSIONS: We observed a median gastric volume of 400 ml in patients after OHCA resuscitation. In our setting, gastric distention did not prevent ROSC.

Radiation in an emergency situation: attempting to respect the patient's beliefs as reported by a minor.

BACKGROUND: Each individual's unique health-related beliefs can greatly impact the patient-clinician relationship. When there is a conflict between the patient's preferences and recommended medical care, it can create a serious ethical dilemma, especially in an emergency setting, and dramatically alter this important relationship. CASE PRESENTATION: A 56-year-old man, who remained comatose after out-of-hospital cardiac arrest, was rushed to our hospital. The patient was scheduled for emergency coronary angiography when his adolescent daughter reported that she and her father held sincere beliefs against radiation exposure. We were concerned that she did not fully understand the potential consequences if her father did not receive the recommended treatment. A physician provided her with in depth information regarding the risks and benefits of the treatment. While we did not want to disregard her statement, we opted to save the patient's life due to concerns about the validity of her report. CONCLUSIONS: Variations in beliefs regarding medical care force clinicians to incorporate patient beliefs into medical practice. However, an emergency may require a completely different approach. When faced with a patient in a life-threatening condition and unconscious, we should take action to prioritize saving their life, unless we are highly certain about the validity of their advance directives.

An Unusual Presentation of Chest Pain and Laryngeal Discomfort in a Pregnant Woman: A Case Report and Literature Review.

Intramural esophageal dissection (IED), characterized by bleeding into the submucosal space, leads to mucosal separation and dissection. The most prevalent symptoms are sudden chest or retrosternal pain, hematemesis, and dysphagia. Therefore, acute coronary syndrome and aortic dissection are among its most notable differential diagnoses. A 31-year-old pregnant woman presented with acute chest pain, laryngeal discomfort, and hematemesis. Emergency esophagogastroscopy revealed longitudinal mucosal dissection (upper esophagus to esophagogastric junction). The patient was successfully treated by avoiding the ingestion of solid foods. Clinicians should consider a diagnosis of IED for pregnant patients with acute chest pain, especially if hematemesis is present.

Hydrogen inhalation attenuates lung contusion after blunt chest trauma in mice.

BACKGROUND: Lung contusion caused by blunt chest trauma evokes a severe inflammatory reaction in the pulmonary parenchyma that may be associated with acute respiratory distress syndrome. Although hydrogen gas has antioxidant and anti-inflammatory effects and is protective against multiple types of lung injury at safe concentrations, the effects of inhaled hydrogen gas on blunt lung injury have not been previously investigated. Therefore, using a mouse model, we tested the hypothesis that hydrogen inhalation after chest trauma would reduce pulmonary inflammation and acute lung injury associated with lung contusion. METHODS: Inbred male C57BL/6 mice were randomly divided into 3 groups: sham with air inhalation, lung contusion with air inhalation, and lung contusion with 1.3% hydrogen inhalation. Experimental lung contusion was induced using a highly reproducible and standardized apparatus. Immediately after induction of lung contusion, mice were placed in a chamber exposed to 1.3% hydrogen gas in the air. Histopathological analysis and real-time polymerase chain reaction in lung tissue and blood gas analysis were performed 6 hours after contusion. RESULTS: Histopathological examination of the lung tissue after contusion revealed perivascular/intra-alveolar hemorrhage, perivascular/interstitial leukocyte infiltration, and interstitial/intra-alveolar edema. These histological changes and the extent of lung contusion, as determined by computed tomography, were significantly mitigated by hydrogen inhalation. Hydrogen inhalation also significantly reduced inflammatory cytokine and chemokine mRNA levels and improved oxygenation. CONCLUSION: Hydrogen inhalation therapy significantly mitigated inflammatory responses associated with lung contusion in mice. Hydrogen inhalation therapy may be a supplemental therapeutic strategy for treating lung contusion.

Successfully treated case of severe hypothermia secondary to myxedema coma.

Background: Myxedema coma is an extremely rare but fatal endocrine emergency that requires urgent recognition and treatment. We describe a case of severe hypothermia that rapidly deteriorated to cardiac arrest that was attributed to myxedema coma. Case Presentation: A 52-year-old man without a history of hypothyroidism was transferred to our emergency department due to coma and profound hypothermia. The patient developed cardiac arrest immediately after hospital arrival but return of spontaneous circulation was achieved shortly after resuscitation. The patient was noted to have generalized, nonpitting edema, dry skin, severe respiratory acidosis, hyponatremia, and elevated creatinine kinase, which was indicative of hypothyroidism. Myxedema coma was confirmed by a thyroid profile. The patient was successfully treated with intravenous levothyroxine and glucocorticoid. Conclusion: Although myxedema coma is a rare cause of severe hypothermia, emergency physicians should be familiar with its clinical features and management.

Luminal administration of biliverdin ameliorates ischemia-reperfusion injury following intestinal transplant in rats.

BACKGROUND: Intestinal grafts are susceptible to ischemia-reperfusion injury, resulting in the loss of mucosal barrier function and graft failure. Biliverdin is known to exert a variety of cytoprotective functions against oxidative tissue injury. Because the mucosal layer is the primary site of ischemia-reperfusion injury, mucosa-targeting strategies by luminal delivery of reagents might be beneficial. We tested whether intraluminal administration of biliverdin as an adjuvant to standard preservation solutions protected against ischemia-reperfusion injury. METHODS: Orthotopic syngeneic intestinal transplants were performed on Lewis rats after 6 hours of cold preservation. Saline containing biliverdin (10 µM) or without biliverdin was introduced into the lumen of the intestinal grafts immediately before cold preservation. RESULTS: Damage to the intestinal mucosa caused by ischemia-reperfusion injury resulted in severe morphological changes, including blunting of the villi and erosion, and led to significant loss of gut barrier function 3 hours after reperfusion. These changes to the mucosa were notably ameliorated by intraluminal administration of biliverdin. Biliverdin also effectively inhibited upregulation of messenger RNAs for interleukin-6, inducible nitric oxide synthase, and C-C motif chemokine 2. Additionally, biliverdin treatment prevented the loss of expression of claudin-1, a transmembrane, tight-junction barrier protein. The 14-day survival of recipients of biliverdin-treated grafts was significantly improved as compared with the recipients of saline-treated control grafts (83.3% vs 38.9%, P = .030). CONCLUSION: This study demonstrated that luminally delivered biliverdin provides beneficial effects during the transplant of rat small intestinal grafts and could be an attractive therapeutic option in organ transplantation.

The microbiome restrains melanoma bone growth by promoting intestinal NK and Th1 cell homing to bone.

Bone metastases are frequent complications of malignant melanoma leading to reduced quality of life and significant morbidity. Regulation of immune cells by the gut microbiome influences cancer progression, but the role of the microbiome in tumor growth in bone is unknown. Using intracardiac or intratibial injections of B16-F10 melanoma cells into mice, we showed that gut microbiome depletion by broad-spectrum antibiotics accelerated intraosseous tumor growth and osteolysis. Microbiome depletion blunted melanoma-induced expansion of intestinal NK cells and Th1 cells and their migration from the gut to tumor-bearing bones. Demonstrating the functional relevance of immune cell trafficking from the gut to the bone marrow (BM) in bone metastasis, blockade of S1P-mediated intestinal egress of NK and Th1 cells, or inhibition of their CXCR3/CXCL9-mediated influx into the BM, prevented the expansion of BM NK and Th1 cells and accelerated tumor growth and osteolysis. Using a mouse model, this study revealed mechanisms of microbiota-mediated gut-bone crosstalk that are relevant to the immunological restraint of melanoma metastasis and tumor growth in bone. Microbiome modifications induced by antibiotics might have negative clinical consequences in patients with melanoma.

State-of-the-art methods for the treatment of severe hemorrhagic trauma: selective aortic arch perfusion and emergency preservation and resuscitation-what is next?

Trauma is a primary cause of death globally, with non-compressible torso hemorrhage constituting an important part of "potentially survivable trauma death." Resuscitative endovascular balloon occlusion of the aorta has become a popular alternative to aortic cross-clamping under emergent thoracotomy for non-compressible torso hemorrhage in recent years, however, it alone does not improve the survival rate of patients with severe shock or traumatic cardiac arrest from non-compressible torso hemorrhage. Development of novel advanced maneuvers is essential to improve these patients' survival, and research on promising methods such as selective aortic arch perfusion and emergency preservation and resuscitation is ongoing. This review aimed to provide physicians in charge of severe trauma cases with a broad understanding of these novel therapeutic approaches to manage patients with severe hemorrhagic trauma, which may allow them to develop lifesaving strategies for exsanguinating trauma patients. Although there are still hurdles to overcome before their clinical application, promising research on these novel strategies is in progress, and ongoing development of synthetic red blood cells and techniques that reduce ischemia-reperfusion injury may further maximize their effects. Both continuous proof-of-concept studies and translational clinical evaluations are necessary to clinically apply these hemostasis approaches to trauma patients.

Restrictive transfusion strategy for critically injured patients (RESTRIC) trial: a study protocol for a cluster-randomised, crossover non-inferiority trial.

INTRODUCTION: Resuscitation using blood products is critical during the acute postinjury period. However, the optimal target haemoglobin (Hb) levels have not been adequately investigated. With the restrictive transfusion strategy for critically injured patients (RESTRIC) trial, we aim to compare the restrictive and liberal red blood cell (RBC) transfusion strategies. METHODS AND ANALYSIS: This is a cluster-randomised, crossover, non-inferiority trial of patients with severe trauma at 22 hospitals that have been randomised in a 1:1 ratio based on the use of a restrictive or liberal transfusion strategy with target Hb levels of 70-90 or 100-120 g/L, respectively, during the first year. Subsequently, after 1-month washout period, another transfusion strategy will be applied for an additional year. RBC transfusion requirements are usually unclear on arrival at the emergency department. Therefore, patients with severe bleeding, which could lead to haemorrhagic shock, will be included in the trial based on the attending physician's judgement. Each RBC transfusion strategy will be applied until 7 days postadmission to the hospital or discharge from the intensive care unit. The outcomes measured will include the 28-day survival rate after arrival at the emergency department (primary), the cumulative amount of blood transfused, event-free days and frequency of transfusion-associated lung injury and organ failure (secondary). Demonstration of the non-inferiority of restrictive transfusion will emphasise its clinical advantages. ETHICS AND DISSEMINATION: The trial will be performed according to the Japanese and International Ethical guidelines. It has been approved by the Ethics Committee of each participating hospital and The Japanese Association for the Surgery of Trauma (JAST). Written informed consent will be obtained from all patients or their representatives. The results of the trial will be disseminated to the participating hospitals and board-certified educational institutions of JAST, submitted to peer-reviewed journals for publication, and presented at congresses. TRIAL REGISTRATION NUMBER: UMIN Clinical Trials Registry; UMIN000034405. Registered 8 October 2018.

Therapeutic strategies for ischemia reperfusion injury in emergency medicine.

Ischemia reperfusion (IR) injury occurs when blood supply, perfusion, and concomitant reoxygenation is restored to an organ or area following an initial poor blood supply after a critical time period. Ischemia reperfusion injury contributes to mortality and morbidity in many pathological conditions in emergency medicine clinical practice, including trauma, ischemic stroke, myocardial infarction, and post-cardiac arrest syndrome. The process of IR is multifactorial, and its pathogenesis involves several mechanisms. Reactive oxygen species are considered key molecules in reperfusion injury due to their potent oxidizing and reducing effects that directly damage cellular membranes by lipid peroxidation. In general, IR injury to an individual organ causes various pro-inflammatory mediators to be released, which could then induce inflammation in remote organs, thereby possibly advancing the dysfunction of multiple organs. In this review, we summarize IR injury in emergency medicine. Potential therapies include pharmacological treatment, ischemic preconditioning, and the use of medical gases or vitamin therapy, which could significantly help experts develop strategies to inhibit IR injury.

Potentially fatal ingestion of heat-not-burn cigarettes successfully treated by gastric lavage.

Newly introduced heat-not-burn or electronic cigarettes can cause lethal nicotine intoxication if ingested at higher doses. Although routine gastric lavage is not recommended, it should be considered if the amount of intoxicant is lethal. A 59-year-old man with a history of depression was brought to our emergency department after intentional ingestion of 8 heat-not-burn cigarettes, which were estimated to contain a total of 100 mg of nicotine. Abdominal computed tomography confirmed the gastric contents, detecting multiple stick-like and rod-shaped high-density structures. Gastric lavage was performed to minimize absorption of the potentially lethal nicotine dose. The patient exhibited only mild gastrointestinal symptoms. Emergency physicians should be aware of this novel heat-not-burn cigarette and its toxicity.

Huge abdominal cerebrospinal fluid pseudocyst following ventriculoperitoneal shunt: a case report.

INTRODUCTION: Abdominal pseudocysts comprising cerebrospinal fluid are an uncommon but significant complication in patients with ventriculoperitoneal shunt. We present a successfully treated 12-year-old boy with a history of ventriculoperitoneal shunting and a huge abdominal cerebrospinal fluid pseudocyst. CASE PRESENTATION: A12-year-old Japanese boy presented with a deteriorated consciousness and a palpable and elastic large lower abdominal mass. Computed tomography of his abdomen demonstrated a collection of homogenous low-density fluid near the catheter tip of the ventriculoperitoneal shunt. Cerebral computed tomography revealed an increased ventricular size. Based on the clinical diagnosis of abdominal pseudocyst, the peritoneal shunt catheter was secured and divided into two parts by cutting it on the chest; then, the proximal side of the peritoneal shunt catheter was externalized for extraventricular drainage. The cyst was percutaneously aspirated with ultrasound guidance, and the distal side of the peritoneal shunt catheter was removed. The distal side of the peritoneal shunt catheter was reinserted in another position into his abdomen after 3-week extraventricular drainage management. CONCLUSION: Emergency physicians should know about this potential complication as an important differential diagnosis resulting from acute abdominal complaints in patients with ventriculoperitoneal shunts.

Hydrogen gas inhalation ameliorates lung injury after hemorrhagic shock and resuscitation.

BACKGROUND: Hemorrhagic shock and resuscitation (HSR) is known to cause inflammatory reactions in the lung parenchyma and acute lung injury, increasing the risk of complications that can lead to death. Hydrogen gas has shown to inhibit the formation and eliminate reactive oxygen species (ROS), which are known to cause reperfusion injury. Hence, the purpose of this study was to investigate the protective effect of 2% inhaled hydrogen gas on post-HSR lung injury. METHODS: Rats weighing 300-500 g were divided into three groups: sham, HSR, and hydrogen (H2)/HSR groups. In the latter two groups, HSR was induced via femoral vein cannulation. Gas containing 2% hydrogen gas was inhaled only by those in the H2/HSR group. Lung tissue and abdominal aorta blood were obtained for histologic examination and arterial blood gas analyses, respectively. Neutrophil infiltration and proinflammatory mediators were also measured. RESULTS: PO2 was lower in the HSR and H2/HSR groups than in the sham group. Blood lactate level was not significantly different between the sham and H2/HSR groups, but it was significantly higher in the HSR group. Infiltration of inflammatory cells into the lung tissues was more frequent in the HSR group. Myeloperoxidase (MPO) activity was significantly different among the three groups (highest in the HSR group). All proinflammatory mediators, except IL-6, showed a significant difference among the three groups (highest in the HSR group). CONCLUSIONS: Inhalation of 2% hydrogen gas after HSR minimized the extent of lung injury by decreasing MPO activity and reducing infiltration of inflammatory cells into lung tissue.

Gastric Emphysema in a Critically Ill Patient Successfully Treated without Surgery.

Gastric emphysema is a relatively rare clinical entity caused by injury to the gastric mucosa. A 62-year-old Japanese male with a history of heavy alcohol consumption and smoking was admitted to the emergency intensive care unit due to severe hypercapnic respiratory acidosis. His body mass index was only 12.6. Ten days after initiation of enteral feeding, he complained of abdominal pain. Computed tomography revealed intraluminal air in the distended gastric wall. Esophagogastroduodenoscopy showed diffuse edema, redness, and erosion throughout the stomach. Based on the findings of narrow angle and short distance of the aorta-superior mesenteric artery, the patient was diagnosed with gastric emphysema associated with superior mesenteric artery syndrome. He was successfully managed nonoperatively with treatments including intravenous antibiotics, gastric decompression, and bowel rest. Physicians should be aware of this unusual condition in such critically ill patients complaining of abdominal pain and needing close monitoring and observation to exclude gastric necrosis or perforation.

Mortality in trauma patients admitted during, before, and after national academic emergency medicine and trauma surgery meeting dates in Japan.

Annually, many physicians attend national academic meetings. While participating in these meetings can have a positive impact on daily medical practice, attendance may result in reduced medical staffing during the meeting dates. We sought to examine whether there were differences in mortality after trauma among patients admitted to the hospital during, before, and after meeting dates. Using the Japan Trauma Data Bank, we analyzed in-hospital mortality in patients with traumatic injury admitted to the hospital from 2004 to 2015 during the dates of two national academic meetings-the Japanese Association for Acute Medicine (JAAM) and the Japanese Association for the Surgery of Trauma (JAST). We compared the data with that of patients admitted with trauma during identical weekdays in the weeks before and after the meetings, respectively. We used multiple logistic regression analysis to compare outcomes among the three groups. A total of 7,491 patients were included in our analyses, with 2,481, 2,492, and 2,518 patients in the during, before, and after meeting dates groups, respectively; their mortality rates were 7.3%, 8.0%, and 8.5%, respectively. After adjusting for covariates, no significant differences in in-hospital mortality were found among the three groups (adjusted odds ratio [95% CI] of the before meeting dates and after meeting dates groups; 1.18 [0.89-1.56] and 1.23 [0.93-1.63], respectively, with the during meeting dates group as the reference category). No significant differences in in-hospital mortality were found among trauma patients admitted during, before, and after the JAAM and JAST meeting dates.

Impact of contrast extravasation on computed tomography of the psoas major muscle in patients with blunt torso trauma.

BACKGROUND: The clinical significance of contrast extravasation (CE) on computed tomography (CT) of the psoas major muscle after blunt torso trauma and the optimal management of patients requiring transcatheter arterial embolization (TAE) of the lumbar artery have not been well elucidated. The aim of this study was to investigate the impact of CE on CT to determine the need for TAE of the lumbar artery. METHODS: We examined a single-center retrospective cohort of blunt torso trauma patients who underwent contrast-enhanced CT from 2008 to 2017. Basic demographics and clinical data were obtained, including the number of lumbar transverse process fractures (LTPFs) and maximum psoas major muscle hematoma (PMMH) size and ratio. Maximum PMMH size was analyzed by measuring the cross-sectional area of hematoma size at the level of CE. Psoas major muscle hematoma size ratio was obtained by dividing maximum PMMH size by psoas major muscle size of the unaffected side at the same slice level. RESULTS: A total of 762 patients were included. One hundred seventeen patients had LTPFs and/or PMMH. Of 117 patients, 25 had CE on CT of the psoas major muscle and had significantly higher rates of older age and severe injury compared with those without CE. Of the 25 patients with CE, 13 required TAE of the lumbar artery. Patients who required TAE had a significantly higher number of LTPFs (4 vs. 2, p = 0.011) and higher PMMH size ratio (2.10 vs. 1.32, p = 0.016). Psoas major muscle hematoma size ratio revealed moderate accuracy (area under the receiver operating characteristic curve, 0.782). CONCLUSIONS: Approximately half of the blunt torso trauma patients with CE on CT of the psoas major muscle will require TAE of the lumbar artery. Higher number of LTPFs and larger PMMH size can be a predictor of the need for TAE of the lumbar artery among patients with CE on CT. LEVEL OF EVIDENCE: Therapeutic/care management, level IV.