Max Daniel Kauther

Prehospital intubation of the moderately injured patient: a cause of morbidity? A matched-pairs analysis of 1,200 patients from the DGU Trauma Registry

IntroductionHypoxia and hypoxemia can lead to an unfavorable outcome after severe trauma, by both direct and delayed mechanisms. Prehospital intubation is meant to ensure pulmonary gas exchange. Limited evidence exists regarding indications for intubation after trauma. The aim of this study was to analyze prehospital intubation as an independent risk factor for the posttraumatic course of moderately injured patients. Therefore, only patients who, in retrospect, would not have required intubation were included in the matched-pairs analysis to evaluate the risks related to intubation.MethodsThe data of 42,248 patients taken from the trauma registry of the German Association for Trauma Surgery (Deutsche Gesellschaft für Unfallchirurgie (DGU)) were analyzed. Patients who met the following criteria were included: primary admission to a hospital; Glasgow Coma Scale (GCS) of 13 to 15; age 16 years or older; maximum injury severity per body region (AIS) ≤ 3; no administration of packed red blood cell units in the emergency trauma room; admission between 2005 and 2008; and documented data regarding intubation. The intubated patients were then matched with not-intubated patients.ResultsThe study population included 600 matched pairs that met the inclusion criteria. The results indicated that prehospital intubation was associated with a prolonged rescue time (not intubated, 64.8 minutes; intubated, 82.3 minutes; P ≤ 0.001) and a higher volume replacement (not intubated, 911.3 ml; intubated, 1,573.8 ml; P ≤ 0.001). In the intubated patients, coagulation parameters, such as the prothrombin time ratio (PT) and platelet count, declined, as did the hemoglobin value (PT not intubated: 92.3%; intubated, 85.7%; P ≤ 0.001; hemoglobin not intubated, 13.4 mg/dl; intubated, 12.2 mg/dl; P ≤ 0.001). Intubation at the scene resulted in an elevated sepsis rate (not intubated, 1.5%; intubated, 3.7%; P ≤ 0.02) and an elevated prevalence of multiorgan failure (MOF) and organ failure (OF) (OF not intubated, 9.1%; intubated, 23.4%; P ≤ 0.001).ConclusionsPrehospital intubation in trauma patients is associated with a number of risks and should be critically weighed, except in cases with clear indicators, such as posttraumatic apnea.

Breakdance injuries and overuse syndromes in amateurs and professionals.

Background Serious injuries due to breakdancing have been presented only as singular case reports to date. So far, there have been no comprehensive studies about injuries in this sport. Hypothesis Professional breakdancing might lead to a higher incidence of injuries than amateur training. Wearing safety equipment is correlated with a decreased incidence of injuries and pain. Study Design Descriptive epidemiology study. Methods The retrospective study surveyed 40 breakdance professionals and 104 amateurs by questionnaire. Results There were 1665 injuries and 206 overuse syndromes found in 380 588 hours of training, leading to a loss of 10 970.6 training days. Professionals reported significantly (P < .001) more injuries and overuse syndromes with significantly more injuries of the wrist (P < .001), knee (P < .001), hip/thigh (P = .003), ankle/foot (P = .013), and elbow (P = .033). No significant differences were found in the time lost per injury and the time lost per overuse syndrome. Pain occurred most frequently in the region of the wrist, spine, shoulder, and ankle. A negative correlation between protective gear and injuries or frequency of pain could not be shown. Conclusion Breakdancing must be considered as a potentially high-risk dancing sport. Even with severe injuries, dancers interrupt training only for limited periods of time. Clinical Relevance Breakdance injuries and overuse should not be underestimated. Physicians should be aware of the common risks in this highly acrobatic kind of dancing.

Influence of prehospital volume replacement on outcome in polytraumatized children

IntroductionSevere bleeding after trauma frequently results in poor outcomes in children. Prehospital fluid replacement therapy is regarded as an important primary treatment option. Our study aimed, through a retrospective analysis of matched pairs, to assess the influence of prehospital fluid replacement therapy on the post-traumatic course of severely injured children.MethodsThe data for 67,782 patients from the TraumaRegister DGU® of the German Trauma Society were analyzed. The following inclusion criteria were applied: injury severity score ≥16 points, primary admission, age 1 to 15 years old, systolic blood pressure ≥20 mmHg at the accident site and transfusion of at least one unit of packed red blood cells (pRBC) in the emergency trauma room prior to intensive care admission. As volume replacement therapy depends on age and body weight, especially in children, three subgroups were formed according to the mean value of the administered prehospital volume. The children were matched and enrolled into two groups according to the following criteria: intubation at the accident site (yes/no), Abbreviated Injury Scale (four body regions), accident year, systolic blood pressure and age group.ResultsA total of 31 patients in each group met the inclusion criteria. An increase in volume replacement was associated with an elevated need for a transfusion (≥10 pRBC: low volume, 9.7%; high volume, 25.8%; P = 0.18) and a reduction in the ability to coagulate (prothrombin time ratio: low volume, 58.7%; high volume, 55.6%; P = 0.23; prothrombin time: low volume, 42.2 seconds; high volume, 50.1 seconds; P = 0.38). With increasing volume, the mortality (low volume, 19.4%; high volume, 25.8%; P = 0.75) and multiple organ failure rates (group 1, 36.7%; group 2, 41.4%; P = 0.79) increased. With increased volume, the rescue time also increased (low volume, 62 minutes; high volume, 71.5 minutes; P = 0.21).ConclusionFor the first time, a tendency was shown that excessive prehospital fluid replacement in children leads to a worse clinical course with higher mortality and that excessive fluid replacement has a negative influence on the ability to coagulate.

RANKL-associated suppression of particle-induced osteolysis in an aged model of Calcitonin and α-CGRP deficiency.

An aging population with higher bone turnover intensifies the need for joint replacement surgery. However, particle-induced osteolysis (PIO) remains a major cause of early implant loosening. Differences in bone remodeling between young and aged Calcitonin (CT)- and α-CGRP (Calcitonin gene-related peptide)-deficient mice (Calca(-/-)) might modify our previous findings regarding CT/α-CGRP in PIO. This may have important implications for PIO in an aging population. Four groups of twelve-month-old wild-type and Calca(-/-) mice underwent either SHAM surgery with and without CT, or polyethylene-particle implantation with related treatment. Morphometric changes were detected using μ-CT, histomorphometric analysis and by counting TRAP(+) cells (osteoclast-staining). Bone remodeling was assessed using serum and urinary markers. There was no osteolysis in aged particle-treated Calca(-/-) animals and the effect of CT on PIO was reduced compared to wild-type mice. However, there were significantly higher numbers of TRAP(+) cells in Calca(-/-) animals, and bone remodeling markers revealed a significant increase in OPG/OCN and a significant reduction in RANKL compared to aged wild-type mice. CT/α-CGRP modulates bone cell activity in PIO in aged mice in a way that is distinct from young animals. This may have implications for the treatment of PIO in the periprosthetic surface of joint replacements in an aging population.

Measurement of the Silver Ion Concentration in Wound Fluids after Implantation of Silver-Coated Megaprostheses: Correlation with the Clinical Outcome

Background. Tumor patients and patients after traumas are endangered by a reduced immune defense, and a silver coating on their megaprostheses may reduce their risks of infection. The aim of this study was to determine the silver ion concentration directly measured from the periprosthetic tissue and the influence on the clinical outcome. Material and Methods. Silver ions were evaluated in 5 mL wound fluids two days postoperatively and in blood patients 7 and 14 days after surgery using inductively coupled plasma emission spectrometry in 18 patients who underwent total joint replacement with a silver-coated megaendoprosthesis. Results. The concentration of silver ions averaged 0.08 parts per million. Patients who showed an increased silver concentration in the blood postoperatively presented a lower silver concentration in the wound fluids and a delayed decrease in C-reactive protein levels. There were significantly fewer reinfections and shorter hospitalization in comparison with a group that did not receive a silver-coated megaprosthesis. Conclusion. An increased concentration of silver in the immediate surroundings of silver-coated prostheses was demonstrated for the first time in cohorts of patients with trauma or tumors. An elevated concentration of silver ions in the direct periprosthetic tissue may have reduced the infection rate.

Effects of alpha-calcitonin gene-related peptide on osteoprotegerin and receptor activator of nuclear factor-κB ligand expression in MG-63 osteoblast-like cells exposed to polyethylene particles

BackgroundRecent studies demonstrated an impact of the nervous system on particle-induced osteolysis, the major cause of aseptic loosening of joint replacements.MethodsIn this study of MG-63 osteoblast-like cells we analyzed the influence of ultra-high molecular weight polyethylene (UHMWPE) particles and the neurotransmitter alpha-calcitonin gene-related peptide (CGRP) on the osteoprotegerin/receptor activator of nuclear factor-κB ligand/receptor activator of nuclear factorκB (OPG/RANKL/RANK) system. MG-63 cells were stimulated by different UHMWPE particle concentrations (1:100, 1:500) and different doses of alpha-CGRP (10-7 M, 10-9 M, 10-11 M). RANKL and OPG mRNA expression and protein levels were measured by RT-PCR and Western blot.ResultsIncreasing particle concentrations caused an up-regulation of RANKL after 72 hours. Alpha-CGRP showed a dose-independent depressive effect on particle-induced expression of RANKL mRNA in both cell-particle ratios. RANKL gene transcripts were significantly (P < 0.05) decreased by alpha-CGRP treatment after 48 and 72 hours. OPG mRNA was significantly down-regulated in a cell-particle ratio of 1:500 after 72 hours. Alpha-CGRP concentrations of 10-7 M lead to an up-regulation of OPG protein.ConclusionIn conclusion, a possible osteoprotective influence of the neurotransmitter alpha-CGRP on particle stimulated osteoblast-like cells could be shown. Alpha-CGRP might be important for bone metabolism under conditions of particle-induced osteolysis.

Calcitonin substitution in calcitonin deficiency reduces particle-induced osteolysis

BackgroundPeriprosthetic osteolysis is a major cause of aseptic loosening in joint arthroplasty. This study investigates the impact of CT (calcitonin) deficiency and CT substitution under in-vivo circumstances on particle-induced osteolysis in Calca -/- mice.MethodsWe used the murine calvarial osteolysis model based on ultra-high molecular weight polyethylene (UHMWPE) particles in 10 C57BL/6J wild-type (WT) mice and twenty Calca -/- mice. The mice were divided into six groups: WT without UHMWPE particles (Group 1), WT with UHMWPE particles (Group 2), Calca -/- mice without UHMWPE particles (Group 3), Calca -/- mice with UHMWPE particles (Group 4), Calca -/- mice without UHMWPE particles and calcitonin substitution (Group 5), and Calca -/- mice with UHMWPE particle implantation and calcitonin substitution (Group 6). Analytes were extracted from serum and urine. Bone resorption was measured by bone histomorphometry. The number of osteoclasts was determined by counting the tartrate-resistant acid phosphatase (TRACP) + cells.ResultsBone resorption was significantly increased in Calca -/- mice compared with their corresponding WT. The eroded surface in Calca -/- mice with particle implantation was reduced by 20.6% after CT substitution. Osteoclast numbers were significantly increased in Calca -/- mice after particle implantation. Serum OPG (osteoprotegerin) increased significantly after CT substitution.ConclusionsAs anticipated, Calca -/- mice show extensive osteolysis compared with wild-type mice, and CT substitution reduces particle-induced osteolysis.

Hemipelvectomy- only a salvage therapy?

After the first hemipelvectomy in 1891 significant advances have been made in the fields of preoperative diagnosis, surgical technique and adjuvant treatment in patients with pelvic tumors. The challenging surgical removal of these rare malignant bone or soft tissue tumors accompanied by interdisciplinary therapy is mostly the only chance of cure, but bares the risk of intensive bleeding and infection. The reconstruction after hemipelvectomy is of importance for the later outcome and quality of life for the patient. Here, plastic surgery with microvascular free flaps or local rotational flaps improved the reconstruction and reduced infection rates. Average local recurrence rates of 14% demonstrate good surgical results, but 5 year survival rates of only 50% are described for some tumor entities, showing the importance of a multimodal collaboration. On a basis of a selective literature review the history, indications, treatment options and outcome of hemipelvectomies are presented.

Inhibition of osteoclastogenesis by RNA interference targeting RANK

BackgroundOsteoclasts and osteoblasts regulate bone resorption and formation to allow bone remodeling and homeostasis. The balance between bone resorption and formation is disturbed by abnormal recruitment of osteoclasts. Osteoclast differentiation is dependent on the receptor activator of nuclear factor NF-kappa B (RANK) ligand (RANKL) as well as the macrophage colony-stimulating factor (M-CSF). The RANKL/RANK system and RANK signaling induce osteoclast formation mediated by various cytokines. The RANK/RANKL pathway has been primarily implicated in metabolic, degenerative and neoplastic bone disorders or osteolysis. The central role of RANK/RANKL interaction in osteoclastogenesis makes RANK an attractive target for potential therapies in treatment of osteolysis. The purpose of this study was to assess the effect of inhibition of RANK expression in mouse bone marrow macrophages on osteoclast differentiation and bone resorption.MethodsThree pairs of short hairpin RNAs (shRNA) targeting RANK were designed and synthesized. The optimal shRNA was selected among three pairs of shRNAs by RANK expression analyzed by Western blot and Real-time PCR. We investigated suppression of osteoclastogenesis of mouse bone marrow macrophages (BMMs) using the optimal shRNA by targeting RANK.ResultsAmong the three shRANKs examined, shRANK-3 significantly suppressed [88.3%] the RANK expression (p < 0.01). shRANK-3 also brought about a marked inhibition of osteoclast formation and bone resorption as demonstrated by tartrate–resistant acid phosphatase (TRAP) staining and osteoclast resorption assay. The results of our study show that retrovirus-mediated shRANK-3 suppresses osteoclast differentiation and osteolysis of BMMs.ConclusionsThese findings suggest that retrovirus-mediated shRNA targeting RANK inhibits osteoclast differentiation and osteolysis. It may appear an attractive target for preventing osteolysis in humans with a potential clinical application.

The role of calcitonin receptor signalling in polyethylene particle-induced osteolysis.

The detection of peptides from the calcitonin (CT) family in the periarticular tissue of loosened implants has raised hopes of opening new regenerative therapies in the process of aseptic loosening, which remains the major cause of early implant failure in endoprosthetic surgery. We have previously shown the roles of α-calcitonin gene-related peptide (α-CGRP) and the CALCA gene which encodes α-CGRP/CT in this process. To uncover the role of direct calcitonin receptor (CTR) mediated signalling, we studied particle-induced osteolysis (PIO) in a murine calvaria model with a global deletion of the CTR (CTR-KO) using μCT analysis and histomorphometry. As expected, CTR-KO mice revealed reduced bone volume compared to wild-type (WT) controls (p<0.05). In CTR-KO mice we found significantly higher RANKL (receptor activator of NF-κB ligand) expression in the particle group than in the control group. The increase in osteoclast numbers by the particles was twice as high as the increase of osteoclasts in the WT mice (400 vs. 200%). Changes in the eroded surface and actual osteolysis due to ultrahigh-molecular-weight polyethylene particles were similar in WTs and CTR-KOs. Taken together, our findings strengthen the relevance of the OPG/RANK/RANKL system in the PIO process. CTR seems to have an effect on osteoclast differentiation in this context. As there were no obvious changes of the amount of PIO in CTR deficiency, regenerative strategies in aseptic loosening of endoprosthetic implants based on peptides arising from the CT family should rather focus on the impact of α-CGRP.