Coagulopathy is very common in patients in intensive care unit (ICU) and often indicates organ dysfunction or underlying diseases.The application of traditional methods assessing the patients' coagulation status in ICU is limited because they can not reflect the whole process of coagulation.Thromboelastography (TEG),a point-of-care (POC) assay of coagulation,fibrinolysis and platelet function,developed in recent years has been widely used in organ transplant and cardiovascular surgery and so on.However,there is no standard for the use of TEG in ICU.The development and application of TEG in sepsis,multiple trauma,guiding blood transfusion,extracorporeal membrane oxygenation (ECMO),and anticoagulation monitoring were addressed in this review,and its value and application prospect in ICU were analyzed.

BACKGROUND:Under physiological conditions, nerve roots can move along with the movement of limbs and spine. However, the mechanisms of nerve root stretch injury under physiological conditions and the neurological dysfunction after injury are unclear.
OBJECTIVE:To review the reason of nerve root stretch injury, and to analyze the mechanism of nerve function from biomechanics, pathology and neurophysiology.
METHODS:A computer-based online search of PubMed database was undertaken by the first author to identify the articles related to the research of nerve root injury and nerve stretch injury between 1990 and 2012, with the key words of“nerve root, nerve, stretch injury”. A total of 391 articles were screened out. The articles on the anatomy and biomechanics research of nerve root were included, as wel as the pathology and neurophysiology research after nerve root stretch injury. Final y, 44 articles were included for review.
RESULTS AND CONCLUSION:Nerve root can be stretched along with limbs and spine movement. However, diseases or trauma may cause pathological nerve root stretch, and thus leading neurological dysfunction. The nerve root is often influenced stretch because of its anatomical and tissue structure. Mechanical injury mechanism of stretch composes of peripheral (peripheral nerve conduction stress) and central mechanism (displacement of spinal cord content). Pathological studies found that the local fibrosis is caused by the extracted serum protein that difficult to remove after injury, and this is because of the shortage of lymphatic system in nerve roots. Fibrosis can cause nerve root ischemia, affect the nerve function, and change the biomechanical properties of nerve root. Nerve root injury can cause primary and secondary injury of internal axons, and this is the main reason for neurological dysfunction after injury.

BACKGROUND:Posterior lumbar interbody fusion is a typical therapeutic method of lumbar degenerative disease. Present studies suggested that adjacent segment degeneration occurs after fusion. Recently, more and more scholars paid attention to the development of non-fusion of the spine. ＜br> OBJECTIVE:To compare clinical effects of Dynesys dynamic stabilization system fixation and posterior lumbar interbody fusion in treatment of lumbar degenerative disease. ＜br> METHODS:From July 2009 to July 2011, clinical data of 56 patients with lumbar degenerative disease were retrospectively analyzed. There were 28 cases of Dynesys dynamic stabilization system fixation, and 28 cases of posterior lumbar interbody fusion. Operation time, bleeding volume, and postoperative hospitalization time were compared in both groups. Visual analog scale was used to assess pain. Oswestry disability index was utilized to evaluate clinical effects. ＜br> RESULTS AND CONCLUSION:A total of 56 patients were fol owed up for 18-24 months. Visual analog scale and Oswestry disability index scores were significantly improved at 12 months after treatment in both groups (P＜0.01). Significant differences in operation time, bleeding volume, and postoperative hospitalization time were detected between both groups (P＜0.01). Dynesys dynamic stabilization system group was better than posterior lumbar interbody fusion group. Range of motion was better in the Dynesys dynamic stabilization system group than in the posterior lumbar interbody fusion group (P＜0.01). During fol ow-up, nail rope system and polyester sleeve loose were not detectable in the Dynesys dynamic stabilization system group. These results verified that compared with posterior lumbar interbody fusion, Dynesys dynamic stabilization system for lumbar degenerative diseases has a high safety and smal trauma, and can keep advantages of a fixed segment, and exert a certain effect on degeneration of intervertebral disc in the adjacent segment.

Objective:To study the biocompatibility of porous Ti processed by laser solid forming(LSF)with osteoblasts.Methods:SD rat osteoblasts were seeded on porous Ti surface processed by LSF.Adhesion,proliferation and ALP activity of the osteoblasts were measured at different time,and all samples were observed under SEM.Dense sand-blasted Ti sheets were used as the controls.All data were statistically analyzed.Results:Adhered cells on porous Ti were more than those on nonporous Ti sheets after 2 and 3 hours of culture(P <0.05).At 4 and 7 days,cell proliferation and ALP activity were significantly higher on porous Ti than those on the controls(P <0.05).Conclusion:Porous Ti processed by LSF possesses good biocompatibility with osteoblasts.

Objective To perform anatomic study on percutaneous cannulated-screw fixation of symphysis pubis diastasis in human cadaveric pelvic specimens so as to provide a basis for clinical practice of the technique.Methods Fifteen adult pelvic cadaveric specimens were dissected to expose pubic symphysis,peripheral major vascular nerve,spermatic cord and round ligament of the uterus.Thickness of pubic symphysis and distance between the outer edge of pubic tubercle and spermatic funicle or round ligament of uterus were measured respectively.Distances were measured respectively from entry and exit points to the above-mentioned structures in the direction of guide pin.Entry depth and angles of guide pin with the coronal plane and cross section of the human body were measured.Surgery was simulated to prove the surgery effect through post-surgery filming and CT.Results Thickness of symphysis pubis was gradually reduced from up to down.Pubic tubercle part was the most thick and it could accommodate a 7.3 mm cannulated-screw.Entry and exit points of cannulated-screw were in certain distances with the important nervusvascularis and spematicfunicle (or round ligament of uterus) in the periphery,which were invulnerable to damages in the process of surgery.Proper lengths of cannulated screws were (73.6 ± 1.3) mm for males and (72.4 ± 1.7)mm for females (t =3.146,P ＜ 0.05).Screw thread was completely embedded in pubic tubercle.Angles of guide pin with coronal plane and cross section of human body were (7.3 ± 1.1) °and (6.4 ± 1.0) ° for males (6.9 ± 1.5) ° and (6.1 ± 0.6) ° for females.Radiography and CT findings confirmed that all pin tracks were in the bone substances with angle and length of screws staying within the scope of experiment.Conclusion Percutaneous cannulated screw fixation is reliable and safe for symphysis pubis diastasis.

Objective With the isocentric C-arm (Iso-C) three-dimensional computerized navigation system,cadaveric pelvic specimens were used to imitate double screw fixation of the symphysis pubic.Practicability and safety of the screw trajectory were examined postoperatively by local cadaveric dissections and imaging tests.Methods Pelvic specimens were harvested from 8 male and 7 female adult cadavers.Double screw placement in symphysis pubic was performed using the Iso-C three-dimensional navigation and entry point and safety trajectory was achieved.With the detailed local dissection postoperatively,distances from screw entry and exit points to unilateral structures (spermatic cord,femoral artery and vein,femoral nerve,obturator artery and vein,obtrurator nerve,and so on) were measured respectively.After complete removal of surrounding soft tissues of the specimen with only bony structure kept,the entry angle and length were calculated.Accuracy of double screw fixation of symphysis pubic was further checked using X-ray and CT.Results Entry point of the first screw was at the junction of unilateral pubic tubercle and transitional site of superior pubic ramus.Mean angle of the first screw with the horizontal plane was (7.7 ± 1.9) ° in men and (8.1 ± 1.7) ° in women.Mean angle between the first screw and coronal plane was (7.8 ± 1.8)° in men and (7.7 ±2.0)° in women.Entry point of the second screw was in the same place in the contralateral pubic tubercle.Mean angle between the second screw and horizontal plane was (30.6 ± 4.0) ° in men and (30.8 ± 3.4) ° in women.Mean angle between the second screw and coronal plane was (9.1 ± 3.0)°in men and (9.2 ± 3.3)°in women.Conclusions With the three-dimensional computerized navigation system,the bony channels of double screws implanted in the symphysis pubic are achieved and reliable.Percutaneous double screw fixation is feasible to treat the pubic symphysis diastasis.

Objective: To explore the correlation between thromboelastography (TEG) parameters and the risk of venous thromboembolism (VTE) and bleeding in patients receiving anticoagulant therapy in surgical intensive care unit (SICU). Methods: 205 patients received low molecular weight heparin (LMWH) anticoagulant therapy admitted to SICU of Tianjin Hospital from December 2016 to December 2017 were consecutively enrolled. TEG detection was performed in all patients at 1 day after anticoagulation therapy, and coagulation reaction time (R value), blood clot generation time (K value), blood clot generation rate (α angle) and maximum width value (MA value) were recorded. At the same time, the traditional coagulation function test was carried out, and prothrombin time (PT), activated partial thromboplastin time (APTT) and D-dimer levels were also recorded. The incidence of deep venous thrombosis (DVT), pulmonary embolism (PE) and bleeding during hospitalization were observed. Multivariate Logistic regression analysis was used to analyze the risk factors for VTE and bleeding in patients receiving anticoagulant therapy. Results: Of 205 patients, during the anticoagulant treatment, 14 patients developed DVT, and 4 patients with PE (2 of them were combined with DVT) with an incidence of 7.8% (16/205). There were 2 patients suffering from cerebral hemorrhage, 2 patients with gastric bleeding, and 1 patient with intra-tracheal hemorrhage with an incidence of 2.4% (5/205). Compared with the patients without VTE or bleeding, the R value of TEG in patients with VTE was significantly lowered (minutes: 4.6±2.2 vs. 7.4±1.4, P < 0.01), which was significantly increased in patients with hemorrhagic complications (minutes: 12.1±1.1 vs. 7.4±1.4, P < 0.01). There was no significant difference in the K value, α angle, MA value of TEG, or PT, APTT, D-dimer between the patients with and without VTE or bleeding. Multivariate Logistic regression analysis revealed that the R value of TEG was independent risk factor for incidence of VTE and hemorrhagic complication in SICU patients who receiving anticoagulation therapy [VTE: β = 0.386, odds ratio (OR) = 1.096, 95% confidence interval (95%CI) = 1.021-2.361, P = 0.006; hemorrhagic complication: β = -1.213, OR = 1.051, 95%CI = 1.017-3.458, P = 0.045]. Conclusion The R value of TEG is associated with the occurrence of VTE and hemorrhagic complications in patients receiving anticoagulant therapy in SICU.

Objective: To explore the characteristics and methods of different fixation methods and prevention of open knee joint fracture. Methods: The data of 86 cases of open knee joint fracture admitted from January 2002 to December 2015 in Department of Orthopaedics, Affiliated Hospital of Chengdu University were analyzed retrospectively.There were 65 males and 21 females aged of 38.6 years. There were 38 cases treated with trans articular external fixation alone, 48 cases were in the trans articular external fixation plus auxiliary limited internal fixation group. All the patients were treated according to the same three stages except for different fixation methods. Observation of external fixation and fracture fixation, fracture healing, wound healing and treatment, treatment and related factors of infection control and knee function recovery. χ² test was used to analyze data. Results: Eleven patients had primary wound healing, accounting for 12.8%. Seventy-five patients had two wounds healed, accounting for 87.2%. Only 38 cases of trans articular external fixator group had 31 cases of articular surface reduction, accounting for 81.6%; Five cases of trans articular external fixator assisted limited internal fixation group had 5 cases of poor reduction, accounting for 10.4%; There was significant difference between the two groups (χ²=44.132, P<0.05). Take a single cross joint external fixation group, a total of 23 cases of patients with infection, accounted for 60.5% of external fixation group; trans articular external fixation assisted limited internal fixation group there were 30 cases of patients with infection, accounting for the assistance of external fixator and limited internal fixation group 62.5%; There was significant difference between the two groups(χ²=0.035, P>0.05). Five cases of fracture nonunion cases of serious infection, patients voluntarily underwent amputation. The Lysholm Knee Scale: In the external fixation group, 23 cases were less than 50 points, accounting for 60.5%, 15 cases were more than 50 points, accounting for 39.5%, external fixation and limited internal fixation group 20 cases were less than 50 points, accounting for 41.7%, 28 cases were more than 50 points, accounting for 58.3%; There was significant difference between the two groups(χ²=1.279, P>0.05). Conclusions Prevention and control of infection is a central link in the treatment of open fracture of the knee. Trans articular external fixator plus limited internal fixation is an important measure to treat open fracture of the knee-joint.

OBJECTIVE: To explore the correlation between thromboelastography (TEG) parameters and the risk of venous thromboembolism (VTE) and bleeding in patients receiving anticoagulant therapy in surgical intensive care unit (SICU). METHODS: 205 patients received low molecular weight heparin (LMWH) anticoagulant therapy admitted to SICU of Tianjin Hospital from December 2016 to December 2017 were consecutively enrolled. TEG detection was performed in all patients at 1 day after anticoagulation therapy, and coagulation reaction time (R value), blood clot generation time (K value), blood clot generation rate (α angle) and maximum width value (MA value) were recorded. At the same time, the traditional coagulation function test was carried out, and prothrombin time (PT), activated partial thromboplastin time (APTT) and D-dimer levels were also recorded. The incidence of deep venous thrombosis (DVT), pulmonary embolism (PE) and bleeding during hospitalization were observed. Multivariate Logistic regression analysis was used to analyze the risk factors for VTE and bleeding in patients receiving anticoagulant therapy. RESULTS: Of 205 patients, during the anticoagulant treatment, 14 patients developed DVT, and 4 patients with PE (2 of them were combined with DVT) with an incidence of 7.8% (16/205). There were 2 patients suffering from cerebral hemorrhage, 2 patients with gastric bleeding, and 1 patient with intra-tracheal hemorrhage with an incidence of 2.4% (5/205). Compared with the patients without VTE or bleeding, the R value of TEG in patients with VTE was significantly lowered (minutes: 4.6±2.2 vs. 7.4±1.4, P < 0.01), which was significantly increased in patients with hemorrhagic complications (minutes: 12.1±1.1 vs. 7.4±1.4, P < 0.01). There was no significant difference in the K value, α angle, MA value of TEG, or PT, APTT, D-dimer between the patients with and without VTE or bleeding. Multivariate Logistic regression analysis revealed that the R value of TEG was independent risk factor for incidence of VTE and hemorrhagic complication in SICU patients who receiving anticoagulation therapy [VTE: β = 0.386, odds ratio (OR) = 1.096, 95% confidence interval (95%CI) = 1.021-2.361, P = 0.006; hemorrhagic complication: β = -1.213, OR = 1.051, 95%CI = 1.017-3.458, P = 0.045]. CONCLUSIONS The R value of TEG is associated with the occurrence of VTE and hemorrhagic complications in patients receiving anticoagulant therapy in SICU.
Anticoagulants ; Critical Care ; Heparin, Low-Molecular-Weight ; Humans ; Pulmonary Embolism ; Risk Factors ; Thrombelastography ; Venous Thromboembolism

Objective To investigate the efficacy and safety of regional citrate anticoagulation (RCA) for continuous veno-venous hemofiltration (CVVH) in patients with severe trauma.Methods Sixty-four patients with severe trauma who needed to apply continuous renal replacement therapy (CRRT) and were admitted into the department of critical care medicine in Tianjin Hospital from June 2013 to August 2015 were enrolled in the study.According to the patient's actual condition,they were divided into two groups:no anticoagulant group (29 cases) and RCA group (35 cases).The filter lifetime,after treatment the activated partial thromboplastin time (APTT),acid-base balance,free calcium ([Ca2+]i) and serum sodium (Na+) concentrations,bleeding episodes were compared between the two groups.Results The average filter lifetime in RCA group was longer than that in no anticoagulant group (hours:50.7 ± 11.3 vs.4.9 ± 1.2,P ＜ 0.01).After the end of treatment,the levels of APTT (s:30.7 ± 8.8 vs.32.1 ± 7.3),pH value (7.41 ± 0.09 vs.7.40 ± 0.07),[Ca2+]i (mmol/L:2.13 ± 0.20 vs.2.21 ± 0.17),and Na+ (mmol/L:139 ± 8 vs.141 ± 6) were ofno significant differences between the RCA group and the no anticoagulant group (all P ＞ 0.05).The incidence of clinicalbleeding in RCA group was lower than that in no anticoagulant group [2.9％ (1/35) vs.13.8％ (4/29)],but the differencewas not statistically significant (P ＞ 0.05).Conclusions RCA-CVVH is a safe and effective therapeutic method inpatients with severe trauma who need for CRRT,the stability of internal environment is not affected and no incidence ofclinical bleeding event is increased.