Background/Objectives: Blood lactate concentration is often used to assess systemic hypoperfusion, tissue hypoxia, and sepsis in trauma patients and serves as a prognostic indicator and marker of response to therapy. Point-of-care (POC) devices provide rapid lactate measurements with a single drop of blood. In this study, lactate values from whole blood, measured with two POC devices, Abbott i-STAT^® and the Nova Biomedical Lactate (LA) Plus™ meter, are compared. Methods: An observational analysis of 760 blood samples from four preclinical trauma animal models was performed. Lactate was measured simultaneously with two POC devices (i-STAT^® and the Lactate Plus™ meter). The evaluation in the form of a Bland–Altman diagram showed the agreement of the tests. Results: The Spearman correlation was 0.9180 (95% CI 0.9056 to 0.9288) for i-STAT^® vs. the LA Plus™ meter. Both tests showed a significant increase in lactate after injury (p < 0.05). The i-STAT^® showed a small bias compared to the LA Plus™ meter (−0.0227 ± 0.4542 with 95% limits of agreement from −0.09129 to 0.8675). The LA Plus™ meter showed slightly higher values overall (0.0227 mmol/L), but the i-STAT^® showed higher results at lactate levels above 2.5 mmol/L. Conclusions: The observed similarity in performance between the two devices suggests that both are capable of reliably measuring lactate levels in a trauma situation. The LA Plus™ meter provides fast results with only one drop of blood. This study supports the prehospital use of POC devices.

Background/Objectives: Fecal peritonitis following penetrating abdominal trauma is a serious condition that often results in sepsis and organ failure. The aim of our study was to develop a novel conscious porcine model of sepsis and organ dysfunction caused by multiple penetrating injuries to the small and large intestines. Methods: Twelve female Yorkshire pigs (average weight 50.6 ± 6.5 kg) were divided into two groups: Penetrating Abdominal Trauma (PAT) (n = 8) and Control (n = 4). All surgical procedures were performed under anesthesia with adequate analgesia. In the PAT group, the small and large intestines were punctured, and feces mixed with saline were introduced into the abdominal cavity to induce peritonitis. The Control group received sham surgery with only saline solution. The animals were observed in a conscious state over a period of 72 h, vital parameters were recorded, and blood samples were taken regularly. We adapted a pig-specific SOFA score and developed pig-specific SIRS criteria and NEWS2 score to assess organ function. The model was validated by independent investigators. Results: The survival rate in the PAT group was 75%, with an average survival time of 58.5 h, while all animals in the Control group survived to euthanasia. Monitoring showed pathophysiological changes, such as tachycardia, leucopenia, and thrombocytopenia, indicative of sepsis and organ dysfunction. Blinded investigators independently confirmed the model’s validity. Conclusions: A new swine model of penetrating abdominal trauma and sepsis has been successfully developed that demonstrates significant physiological and immunologic changes comparable to human sepsis. This new model provides a realistic platform for future research into sepsis, its diagnostics, and the evaluation of therapeutic strategies.

Background/Objectives: Extremity trauma represents a significant proportion of battlefield injuries and is prevalent in polytraumatized patients from accidents. Delayed antibiotic treatment and surgical intervention can lead to wound infections, contributing to preventable mortality. This preliminary study aimed to develop a conscious swine model of complex extremity trauma that induces systemic inflammatory response syndrome (SIRS). Methods: All surgical procedures were conducted under anesthesia with sufficient analgesia. All swine were instrumented with a telemetry device and catheters at least 3 days prior to any injury. In phase 1 of model development, a complex extremity injury was performed that consisted of skin and muscle loss, bone defect, severe hemorrhage, and 2 h tourniquet application. In phase 2, multi-drug resistant Gram-positive and Gram-negative bacteria were inoculated topically at the injury site to exacerbate pathophysiological changes towards SIRS. Post-injury, conscious animals were assessed a minimum of twice daily, including pain assessment, neurological response, and vital signs. Blood samples were collected for microbiological testing, complete blood cell counts, and biochemical analysis. Results: After establishing SIRS criteria for Sinclair swine, we developed a model of severe extremity trauma leading to SIRS. During phase 1, resuscitative fluids were reduced and discontinued, with animals surviving 24 h and maintaining SIRS for up to 4 h post-recovery. Phase 2 showed that Gram-negative and Gram-positive pathogens can exacerbate and prolong SIRS. After 72 h, localized infection at the injury site was observed in all animals. Conclusions: We established a new swine model of complex extremity trauma with SIRS. Our model is consistent, reproducible, and relevant to prolonged care scenarios, providing a platform for future research into the evaluation of preventative and therapeutic strategies.

Background/Objectives: The diagnosis of acute compartment syndrome (ACS) of the extremities is typically based on subjective clinical signs and symptoms, highlighting the need for user-friendly diagnostic tools to improve accuracy and reliability. This study evaluates the performance of two commercial devices, the MY01^® continuous pressure monitoring system and the Moxy Monitor near-infrared spectroscopy-based system, against a reference standard of continuous intracompartmental pressure (ICP) monitoring in a preclinical ACS model. Methods: ACS was induced in the anterior compartment of the distal hind limb in eight Yorkshire pigs using a balloon displacement model. ICP was incrementally elevated and maintained for four hours at >30 mmHg above mean arterial pressure. This was followed by balloon deflation and reperfusion. Final assessments were performed at 24 h post-injury. ICP measurements from the MY01^® and muscle oxygen saturation (SmO₂) data from the Moxy Monitor were compared to reference ICP measurements. Histologic analysis of muscle tissue was performed to assess the severity of necrosis. Results: The MY01^® provided accurate ICP measurements, with a mean bias of 2.21 ± 18.77 mmHg during pre-ischemia, 4.86 ± 10.43 mmHg during reperfusion, and 4.69 ± 3.28 mmHg 24 h post-injury, compared to reference probes. Correlation at 24 h post-injury was (r = 0.86, R² = 0.73, p < 0.0001). In contrast, the Moxy Monitor failed to detect significant differences in SmO₂ between injured and control limbs at 24 h post-injury, despite pronounced ICP differences. Our volumetric displacement ACS model demonstrated its efficacy as a testing platform by allowing for controlled, incremental elevation in ICP and sustaining elevated ICP levels after 24 h. Histologic evaluation confirmed extensive muscle damage, including edema and necrosis. Conclusions: The MY01^® provides accurate, continuous ICP monitoring, supporting its clinical utility in ACS diagnosis. However, the use of near-infrared spectroscopy-based systems such as the Moxy Monitor for ACS diagnosis and management should continue to be critically scrutinized.