Abstract： Objective To establish a risk prediction model and risk score for inhospital mortality in heart valve surgery patients, in order to promote its perioperative safety. Methods We collected records of 4 032 consecutive patients who underwent aortic valve replacement, mitral valve repair, mitral valve replacement, or aortic and mitral combination procedure in Changhai hospital from January 1,1998 to December 31,2008. Their average age was 45.90±13.60 years and included 1 876 (46.53%) males and 2 156 (53.57%) females. Based on the valve operated on, we divided the patients into three groups including mitral valve surgery group (n=1 910), aortic valve surgery group (n=724), and mitral plus aortic valve surgery group (n=1 398). The population was divided a 60% development sample (n=2 418) and a 40% validation sample (n=1 614). We identified potential risk factors, conducted univariate analysis and multifactor logistic regression to determine the independent risk factors and set up a risk model. The calibration and discrimination of the model were assessed by the HosmerLemeshow (H-L) test and [CM(159mm]the area under the receiver operating characteristic (ROC) curve,respectively. We finally produced a risk score according to the coefficient β and rank of variables in the logistic regression model. Results The general inhospital mortality of the whole group was 4.74% (191/4 032). The results of multifactor logistic regression analysis showed that eight variables including tricuspid valve incompetence with OR=1.33 and 95%CI 1.071 to 1.648, arotic valve stenosis with OR=1.34 and 95%CI 1.082 to 1.659, chronic lung disease with OR=2.11 and 95%CI 1.292 to 3.455, left ventricular ejection fraction with OR=1.55 and 95%CI 1.081 to 2.234, critical preoperative status with OR=2.69 and 95%CI 1.499 to 4.821, NYHA ⅢⅣ (New York Heart Association) with OR=2.75 and 95%CI 1.343 to 5641, concomitant coronary artery bypass graft surgery (CABG) with OR=3.02 and 95%CI 1.405 to 6.483, and serum creatinine just before surgery with OR=4.16 and 95%CI 1.979 to 8.766 were independently correlated with inhospital mortality. Our risk model showed good calibration and discriminative power for all the groups. P values of H-L test were all higher than 0.05 (development sample: χ2=1.615, P=0.830, validation sample: χ2=2.218, P=0.200, mitral valve surgery sample: χ2=5.175,P=0.470, aortic valve surgery sample: χ2=12.708, P=0.090, mitral plus aortic valve surgery sample: χ2=3.875, P=0.380), and the areas under the ROC curve were all larger than 0.70 (development sample: 0.757 with 95%CI 0.712 to 0.802, validation sample: 0.754 and 95%CI 0.701 to 0806; mitral valve surgery sample: 0.760 and 95%CI 0.706 to 0.813, aortic valve surgery sample: 0.803 and 95%CI 0.738 to 0.868, mitral plus aortic valve surgery sample: 0.727 and 95%CI 0.668 to 0.785). The risk score was successfully established: tricuspid valve regurgitation (mild:1 point, moderate: 2 points, severe:3 points), arotic valve stenosis (mild: 1 point, moderate: 2 points, severe: 3 points), chronic lung disease (3 points), left ventricular ejection fraction (40% to 50%: 2 points, 30% to 40%: 4 points, ＜30%: 6 points), critical preoperative status (3 points), NYHA IIIIV (4 points), concomitant CABG (4 points), and serum creatinine (＞110 μmol/L: 5 points).Conclusion Eight risk factors including tricuspid valve regurgitation are independent risk factors associated with inhospital mortality of heart valve surgery patients in China. The established risk model and risk score have good calibration and discrimination in predicting inhospital mortality of heart valve surgery patients.
Heart valve disease is one of the three most common cardiac diseases,and the patients undergoing valve surgery have been increasing every year. Due to the high mortality,increasing number of valve surgeries,and increasing economic burdens on public health, a lot of risk models for valve surgery have been developed by various countries based on their own clinical data all over the world,which aimed to regulate the preoperative risk assessment and decrease the perioperative mortality. Over the last 10 years, a number of excellent risk models for valve surgery have finally been developed including the Society of Thoracic Surgeons(STS), the Society of Thoracic Surgeons’ National Cardiac Database (STS NCD),New York Cardiac Surgery Reporting System(NYCSRS),the European System for Cardiac Operative Risk Evaluation(EuroSCORE),the Northern New England Cardiovascular Disease Study Group(NNECDSG),the Veterans Affairs Continuous Improvement in Cardiac Surgery Study(VACICSP),Database of the Society of Cardiothoracic Surgeons of Great Britain and Ireland(SCTS), and the North West Quality Improvement Programme in Cardiac Interventions(NWQIP). In this article, we reviewed these risk models which had been developed based on the multicenter database from 1999 to 2009, and summarized these risk models in terms of the year of publication, database, valve categories, and significant risk predictors.
Objective To compare the effects of operative versus nonoperative treatment for displaced intra-articular calcaneal fractures. Methods All randomized controlled trials (RCTs) of operative versus nonoperative treatment for displaced intra-articular calcaneal fractures were identified. Quality assessment and data extraction were performed by two reviewers independently. Results Four published trials involving 530 patients were included. All studies compared operative with nonoperative treatment. It was clear that operative treatment was superior to nonoperative treatment in terms of helping patients back to work, reducing problems wearing shoes, expanding the range of motion of subtalar joint, and improving the recovery of Bohler’s angle. As for foot pain, there was no difference between the two methods. Because the outcome measures varied across the trials, a meta-analysis could not be performed. Conclusions Both operative and nonoperative treatments produce comparable long-term outcomes in the treatment of displaced intra-articular calcaneal fractures. Because of the poor reporting of outcomes, it is not possible to determine if there is any significant difference in outcome measures apart from those listed above. More trials with high methodological quality are needed.
Objective To investigate the effectiveness and long-term stability of small fenestration vertebral bone grafting and transpedicular bone grafting in the treatment of Denis types A and B thoracolumbar burst fractures. Methods Between January 2012 and February 2014, 50 patients with Denis type A or B thoracolumbar burst fractures were treated with vertebroplasty and pedicle screw rod fixation system, and the clinical data were retrospectively analyzed. Small fenestration vertebral bone grafting by trans-interlaminar approach was used in 30 cases (group A), and bone grafting by unilateral transpedicular approach was used in 20 cases (group B). X-ray and CT examinations of the thoracolumbar vertebrae were performed routinely before and after operation. There was no significant difference in sex, age, cause of injury, time from injury to operation, fracture type, injury segment, and preoperative Frankel classification, the percentage of the anterior body height of the injured vertebra, and visual analogue scale (VAS) score between two groups (P>0.05). There was significant difference in preoperative Cobb angle of kyphosis between two groups (P<0.05). The Cobb angle of kyphosis, the percentage of the anterior body height of the injured vertebra, and the recovery of neurological function were recorded and compared between two groups. Results The patients were followed up for 16-31 months (mean, 19.1 months) in group A and for 17-25 months (mean, 20.2 months) in group B. Primary healing of incisions was obtained in the two groups; no nerve injury and other operative complications occurred. The neurological function was improved in varying degrees in the other patients with neurological impairment before operation except patients at grade A of Frankel classification. The lumbar back pain was relieved in two groups. There was significant difference in VAS score between before operation and at 3 months after operation or last follow-up in two groups (P<0.05), but no significant difference was found between at 3 months and last follow-up in two groups and between two groups at each time point after operation (P>0.05). X-ray examination showed that there was no breakage of nail and bar, or dislocation and loosening of internal fixation during follow-up period. The bone grafts filled well and fused in the fractured vertebra. The vertebral height recovered well after operation. The percentage of the anterior body height of the in-jured vertebra and Cobb angle of kyphosis at 1 week, 3 months, and last follow-up were significantly better than preope-rative ones in two groups (P<0.05), but there was no significant difference between different time points after operation (P>0.05), and between two groups at each time point after operation (P>0.05). Conclusion For Denis types A and B thoracolumbar burst fractures, vertebral bone grafting and pedicle screw internal fixation through interlaminal small fene-stration or transpedicular approach can restore the vertebral height, correct kyphosis, and maintain the vertebral stability, which reduce the risk of complications of loosening and breakage of internal fixators. The appropriate bone grafting approach can be chosen based on the degree of spinal canal space occupying, collapse of vertebral and spinal cord injury.
Three dimensional (3D) printing is considered as an advanced manufacturing technology because of its additive nature. Electron beam melting (EBM) is a widely used 3D printing processes for the manufacturing of metal components. However, the products printed via this process generally contain micro porosities which affect mechanical properties, especially the fatigue property. In this paper, two types of EBM printed samples of the Ti-6Al-4V alloy, one with a round cross section and the other with a triangle cross section, were employed to investigate the existence of porosities using computed tomography (CT). Statistical analyses were conducted on the number, volume, shape, and distribution of pores. The results show that small pores (less than 0.000 2 mm3) account for 80% of all pores in each type of samples. Additionally, to some extent, the shape of sample has influence on the number of micro porosities in EBM made Ti-6Al-4V. The sphericity of the pores is relatively low and is inversely proportional to pore volume. It is found that re-melting on the free surface effectively reduce pore density near the surface. This study may help produce a medical implant with better fatigue resistance.
Abstract： Objective To summarize surgical experiences and explore risk factors of patients undergoing repeated heart valve surgery. Methods Clinical records of 325 consecutive patients who underwent repeated heart valve surgery from January 1998 to December 2008 in Changhai Hospital of Second Military Medical University were retrospectively analyzed. There were 149 male patients and 176 female patients with their average age of （47.1±11.8） years. Following variables were collected: preoperative morbidity， heart function， indications and surgical strategies of repeated heart valve surgery， postoperative mortality and morbidity， which were compared with those clinical data of patients who underwent their first heart valve surgery during the same period. Multivariate logistic regression was used to determine risk factors of perioperative death of patients undergoing repeated heart valve surgery. Results The main reasons for repeated heart valve surgery were mitral valve restenosis after closed mitral commissurotomy and new other valvular diseases. Postoperatively， 28 patients died in the early-stage with the overall mortality of 8.6% （28/325）. The main reasons of in-hospital death included low cardiac output syndrome （LCOS）and acute renal failure. Compared with patients undergoing their first heart valve surgery， patients who underwent repeated heart valve surgery were more likely to have chronic obstructive pulmonary disease （COPD)， New York Heart Association (NYHA） classⅢ-Ⅳ， and atrial fibrillation， preoperatively. Their cardiopulmonary bypass time and aortic cross clamp time were comparatively longer. They also had more postoperative morbidities such as LCOS， acute renal failure and acute respiratory distress syndrome （ARDS）. Multivariate logistic regression showed that preoperative critical state （OR=2.82， P=0.002）， cardiopulmonary bypass time longer than 120 minutes （OR=1.13， P=0.008）， concomitant coronary artery bypass grafting （OR=1.64， P=0.005）， postoperative LCOS（OR=4.52， P＜0.001）， ARDS （OR=3.11， P＜0.001） and acute renal failure （OR=4.13， P＜0.001）were independent risk factors of perioperative death of patients undergoing repeated heart valve surgery. Conclusion Repeated heart valve surgery is a difficult surgical procedure with comparatively higher risks. Full preoperative assessment of the valvular lesions， proper timing for surgery and perioperative management are helpful to reduce postoperative mortality and morbidity.
Objective To discuss the effect of three-dimensional (3D) printing individualized model and guide plate in bone tumor surgery. Methods Between October 2015 and December 2016, 3D printing individualized model and guide plate for making preoperative surgical planning and intraoperative treatment were used in 5 patients of bone tumor. All the patients were male, with a median age of 32 years (range, 9-58 years). There were 1 case of cystic echinococcosis at left pelvis and pathological fracture of the proximal femur; 1 case of left iliac bone osteoblastoma associated with aneurysmal bone cyst; 1 case of fibrous dysplasia of the left femur (sheep horn deformity) with pathological fracture; 1 case of metastatic carcinoma of right calcaneus (tumor staging was T2N0M0); and 1 case of Ewing sarcoma of left femur (tumor staging was T2N0M0). The disease duration ranged from 1 month to 10 years (mean, 2.25 years). Results The operation was completed successfully. The operation time was 2.6-7.5 hours (mean, 4.9 hours). The intraoperative blood loss was 200-2 500 mL (mean, 1 380 mL). The intraoperative fluoroscopy times was 1-6 times (mean, 3.8 times). There was no infection after operation, and the blood supply and nerve function were good. All the patients were followed up 3-16 months (mean, 5.4 months). No loosening or breaking of the internal fixator occurred. According to Enneking scoring system, the limb function score was 15-26 (mean, 21); and the results were excellent in 2 cases, good in 2 cases, and fair in 1 case. Conclusion 3D printing technology can make the implementation of the better preoperative planning and evaluation in bone tumor surgery, and it provides a new reference for individualized treatment in patients with bone tumor.
ObjectiveTo investigate the effectiveness of posterior microscopic mini-open technique (MOT) decompression in patients with severe spinal canal stenosis resulting from thoracolumbar burst fractures.MethodsThe clinical data of 28 patients with severe spinal canal stenosis caused by thoracolumbar burst fractures, who were treated by posterior microscopic MOT, which performed unilateral or bilateral laminectomy, poking reduction, intervertebral bone graft via spinal canal, and percutaneous pedicle screw fixation between January 2014 and January 2016 were retrospectively analyzed. There were 21 males and 7 females with a mean age of 42.1 years (range, 16-61 years). The involved segments included T11 in 1 case, T12 in 4 cases, L1 in 14 cases, and L2 in 9 cases. According to AO classification, there were 19 cases of type A3, 9 of type A4. According to American Spinal Injury Association (ASIA) grading, 12 cases were grade C, 13 grade D, and 3 grade E. The time between injury and operation was 3-7 days (mean, 3.6 days). To evaluate effectiveness, the changes in the visual analogue scale (VAS), percentage of anterior height of injured vertebrae, Cobb angle, rate of spinal compromise (RSC), and ASIA grading were analyzed.ResultsAll patients were performed procedures successfully. The operation time was 135-323 minutes (mean, 216.4 minutes). The intraoperative blood loss was 80-800 mL (mean, 197.7 mL). The hospitalization time was 10-25 days (mean, 12.5 days). The incisions healed primarily, without wound infection, cerebrospinal fluid leakage, or other early complications. All the 28 patients were followed up 12-24 months (mean, 16.5 months). No breakage or loosening of internal fixation occurred. All fractures healed, and the healing time was 3-12 months (mean, 6.5 months). Compared with preoperative ones, the percentage of anterior height of injured vertebrae, Cobb angle, and RSC at immediate after operation and at last follow-up and the VAS scores at 1 day after operation and at last-follow were significantly improved (P<0.05). There was no significant difference in the percentage of anterior height of injured vertebrae and Cobb angle between at immediate after operation and at last follow-up (P>0.05). But the RSC at immediate after operation and VSA score at 1 day after operation were significantly improved when compared with those at last follow-up (P<0.05). The ASIA grading at last follow-up was 1 case of grade C, 14 grade D, and 13 grade E, which was significantly improved when compared with preoperative ones (Z=3.860, P=0.000).ConclusionMOT is an effective and minimal invasive treatment for thoracolumbar AO type A3 and A4 burst fractures with severe spinal canal stenosis, and it is beneficial to early rehabilitation for patients.
ObjectiveTo explore the effectiveness of functional reconstruction of hand grasp and pinch by tendon transfers in patients with cervical spinal cord injury.MethodsBetween July 2013 and January 2016, tendon transfer surgery were performed in 21 patients (41 hands) with cervical spinal injury that motion level was located at C6 to reconstruct hand grasp and pinch function. There were 18 males and 3 females with a mean age of 42.3 years (range, 17-65 years). Nineteen patients were with complete spinal cord injury [American Spinal Injury Association (ASIA) grading A], 1 patient was with central cord syndrome whose bilateral hands were completely paralyzed and lower limbs were normal (ASIA grading D), and 1 patient was with cervical spondylotic myelopathy (AISA grading D). The time from injury to hospitalization was 12-22 months (mean, 16.8 months). According to the International classification of surgery of the hand in tetraplegia (ICSHT), there were 6 cases of grade O3, 10 of grade O4, 3 of grade OCu5, and 2 of grade O5. The surgery was divided into two stages with an interval of 6-11 months. At the first stage, grip function was reconstructed in all patients by transfering the extensor carpi radialis longus from radialis side to palmar side through subcutaneous tunnel, and braided and sutured with the flexor pollicis longus and flexor digitorum profundus. At the second stage, the lateral pinch function of the thumb and index finger was reconstructed by braiding and suturing the radial half of the extensor carpi ulnaris (the patients graded as ICSHT O3) or pronator tere (the patients graded above ICSHT O3) with extensor pollicis longus and abductor pollicis longus. The grasp force, the thumb and index finger lateral pinch force, and the maximum fingertips distance between the thumb and index finger were measured at preoperation and at different time points after operation. The modified Lamb and Chan questionnaire, based upon the activities of daily living, was used to evaluate the hand function of all patients at 6 months after sencond stage surgery.ResultsThere was 1 patient with elbow skin lesion, 1 patient with wrist stiffness; both of them recovered after corresponding treatment. All the 21 patients were followed up 15-32 months (mean, 19.6 months) without wound infection, tendon adhesion, tendon rupture, and other complications. The grasp forces of all patients were significantly improved at 4 weeks, 3 months, 6 months, and 1 year after the first stage surgery when compared with preoperative value (P<0.05); and no significant difference was found between different time points after operation (P>0.05). The thumb and index finger lateral pinch force and the maximum fingertips distance between the thumb and index finger of all patients were also significantly improved at 4 weeks, 3 months, 6 months, and 1 year after the second stage surgery when compared with preoperative values (P<0.05); and no significant difference was found between different time points after operation (P>0.05). And there was no significant difference of above indexes between the patients graded as ICSHT O3 and above ICSHT O3 (P>0.05). The functional outcome was good in 19 cases, fair in 1 case, and poor in 1 case according to modified Lamb and Chan questionnaire at 6 months after second stage surgery.ConclusionTendon transfer can significantly improve the hand function and the quality of life of the patients with complete cervical spinal cord injury.