Correlation between kidney and peripheral nerve functions in Type 2 diabetes

BACKGROUND

Although greater impairments in nerve functions parameters are most likely to occur with a lower kidney function, there is a paucity of information on the relationship between the kidney and peripheral nerve functions parameters in Type 2 diabetes.

AIM

To address the impact of peripheral nerve functions in Type 2 diabetes patients in different stages of chronic kidney diseases (CKD).

DESIGN

This prospective study enrolled 238 patients with Type 2 diabetes at a tertiary medical center.

METHOD

We designed composite amplitude scores of nerve conductions (CAS) as a measure of severity of peripheral neuropathy (PN), and used estimated glomerular filtration rate (eGFR) and urine albumin-creatinine ratio (UACR) parameters to stage CKD in Type 2 diabetes patients. The intrapersonal mean, standard deviation and coefficient of variation of eGFR for 238 patients were obtained in the 3 years prior to the study.

RESULTS

The patients who had lower eGFR and higher UACR were older, with longer diabetes duration, a greater percentage of retinopathy and PN and higher CAS. Multiple linear regression analysis revealed that diabetes duration and eGFR were independently associated with CAS, and a cut-off value of eGFR in the presence of PN was 65.3 ml/min/1.73 m2.

CONCLUSION

We observed a close relationship between the severity of kidney and peripheral nerve function in patients with diabetes. If a patient's eGFR value is below 65.3 ml/min/1.73 m2 or the UACR value is above 98.6 mg/dl, caution is needed with the presence of PN even in diabetic patients who are asymptomatic.

The outcomes of statin therapy in patients with acute ischemic stroke in Taiwan: a nationwide epidemiologic study

BACKGROUND

Acute stroke is the third leading cause of death in Taiwan. Although statin therapy is widely recommended for stroke prevention, little is known about the epidemiology of statin therapy after acute ischemic stroke (AIS) in Taiwan. To investigate the effects of statin therapy on recurrent stroke, intracranial hemorrhage (ICH), coronary artery disease (CAD), cost of hospitalization and mortality, we conducted a nationwide population-based epidemiologic study.

METHODS

Cases of AIS were identified from the annual hospitalization discharge diagnoses of the National Health Insurance Research Database with the corresponding International Classification of Diseases, ninth revision codes from January 2001 to December 2010. We divided the AIS patients into three groups: non-statin, pre-stroke statin and post-stroke statin.

RESULTS

A total of 422 671 patients with AIS (including 365 419 cases in the non-statin group, 22 716 cases in the pre-stroke statin group and 34 536 cases in the post-stroke statin group) were identified. When compared to the non-statin group, both statin groups had a lower recurrent stroke risk [pre-stroke statin: odds ratio (OR) = 0.84; 95% confidence interval (CI) = 0.82-0.87; P < 0.0001; post-stroke statin: OR = 0.89; 95% CI = 0.86-0.91; P < 0.0001], lower ICH risk (pre-statin: OR = 0.75; 95% CI = 0.69-0.82; P < 0.0001; post-stroke statin: OR = 0.75; 95% CI = 0.71-0.81; P < 0.0001), and a lower mortality rate (pre-stroke statin: OR = 0.56; 95% CI = 0.53-0.59; P < 0.0001; post-stroke statin: OR = 0.51; 95% CI = 0.48-0.53; P < 0.0001). In terms of CAD, only the post-statin group had a lower risk (OR = 0.81; 95% CI = 0.79-0.84; P < 0.0001) than the non-statin group. The post-statin group had the lowest 1-year medical costs after index discharge among the three groups.

CONCLUSIONS

Statin therapy reduced the risks of recurrent stroke, CAD, ICH and the first year mortality in patients after AIS. Treatment with statin therapy after AIS is a cost-effective strategy in Taiwan.

Outcomes of Heart Transplant Recipients With Preexisting Malignancies

BACKGROUND

Ensuring careful selection of heart transplant recipients with pretransplant malignancies (PTM) has been suggested in several retrospective studies. However, cancer survival rates continue to increase and we still lack outcomes data on PTM patients who have undergone heart transplantation (HT) within the Asian region. Herein we report pretransplant characteristics and outcomes among PTM patients with HT.

METHODS

A total of 354 patients underwent HT from January 2004 to January 2016. Eight of these patients had a history malignancy that was being treated before transplantation. Posttransplant outcomes and clinical characteristics were collected and possible prognostic factors analyzed.

RESULTS

The median age of the patients with a preexisting malignancy was 60 years. The PTM group included 5 males and 3 females, with a median duration of follow-up of 43 months. In this group there were 2 patients with lymphoma after chemotherapy, 1 with colon cancer postoperatively, and 1 was on chemotherapy. In the other 4 patients, nasopharyngeal cancer, thyroid cancer, breast cancer, and endometrial cancer were identified, and each had undergone treatment. Only 1 premalignancy patient, with nasopharyngeal cancer, had disease recurrence. The 5-year overall survival of these patients was 50.0 ± 17.7%, but 5-year survival for those without PTM was 68.7 ± 2.0%.

CONCLUSION

PTM was 2.3% in our cohort. PTM is associated with an increased risk of all-cause mortality. Thus, our findings suggest careful consideration when selecting PTM patients for HT.

Neuropsychiatric symptoms in Alzheimer's disease: associations with caregiver burden and treatment outcomes

BACKGROUND

Caregivers play a major role in providing care for patients with Alzheimer's disease (AD) and are themselves at higher risk of health comorbidities.

AIM

To address the impact of neuropsychiatric symptoms of patients in different stages of AD on their caregivers' burden.

DESIGN

This prospective study enrolled 260 AD patients with clinical dementia rating (CDR) of 0.5, 1 and 2 at a tertiary medical center.

METHODS

All patients were tested using the mini-mental state examination (MMSE), the cognitive abilities screening instrument (CASI), the neuropsychiatric inventory (NPI) and the CDR scale. Data regarding therapeutic outcomes of anti-Alzheimer's drugs were also collected. Caregivers were tested using NPI.

RESULTS

The mean follow-up interval was 25.0 ± 12.2 months, and two patients died during follow-up. NPI-burden was positively correlated with NPI-sum ( r  = 0.822, P  <   0.001) but negatively correlated with years of education ( r  = -0.140, P  =   0.024), CASI score ( r  = -0.259, P  <   0.001) and MMSE score ( r  = -0.262, P  <0.001). Multiple linear regression analysis showed that only NPI-sum was independently associated with mean NPI-burden. Both higher mean CASI and MMSE scores had better therapeutic outcome of anti-Alzheimer's drugs ( P  =   0.001 and P =   0.005, respectively).

CONCLUSIONS

The severity of neuropsychiatric symptoms in patients with AD was positively associated with caregiver's stress, and patients with better cognitive functions, under treatment with anti-Alzheimer's drugs, had better therapeutic outcomes. To reduce the impact of neuropsychiatric symptoms, it is crucial to detect dementia in its early phases and provide early intervention with anti-Alzheimer's drugs, which might help decrease the caregiver burden, thereby improving their quality of life.

Long-term results of coronary artery bypass grafting in patients with dialysis-dependent renal failure

AIM

Coronary artery disease is the main cause of mortality and morbidity in dialysis-dependent renal failure patients. Both the prevalence and incidence of renal failure are high in Taiwan. However, there were few reports exploring the outcome of coronary aortic bypass grafting (CABG) in these patients. The aim of this study was to determine the survival outcome and risk factors for mortality from CABG in this population.

METHODS

The operative, early postoperative and late results of 170 dialysis patients undergoing isolated coronary artery bypass grafting from January, 2000 to January, 2012 were retrospectively reviewed. Operative mortality, long-term survival, and risk factors were analyzed.

RESULTS

One hundred and seventeen patients (68.8%) were male, and the mean age was 61.5±10.3 years (range, 34-86 years). Follow-up was 40.3±32.1 months. Operative mortality was 8.2%. Actuarial survival, including operative mortality, was 81±3% at 1 year, 68±4% at 3 years, 58±5% at 5 years and 49±6% at 10 years, better than the natural course of dialysis-dependent renal failure patients. Age, emergent operation, postoperative ventricular tachycardia or fibrillation, postoperative intra-aortic balloon pump insertion, gastrointestinal bleeding, and left internal mammary artery graft were significant predictors of operative or long term mortality. Most causes of late death were due to infection or cardiac events.

CONCLUSION

CABG in dialysis patients is associated with a higher incidence of complications, but has acceptable mortality. CABG is beneficial in this population. Internal mammary artery grafting may provide more favorable long term outcomes.

Neuroprotective effect of agmatine in rats with transient cerebral ischemia using MR imaging and histopathologic evaluation

PURPOSE

This study aimed to further investigate the effects of agmatine on brain edema in the rats with middle cerebral artery occlusion (MCAO) injury using magnetic resonance imaging (MRI) monitoring and biochemical and histopathologic evaluation.

MATERIALS AND METHODS

Following surgical induction of MCAO for 90min, agmatine was injected 5min after beginning of reperfusion and again once daily for the next 3 post-operative days. The events during ischemia and reperfusion were investigated by T2-weighted images (T2WI), serial diffusion-weighted images (DWI), calculated apparent diffusion coefficient (ADC) maps and contrast-enhanced T1-weighted images (CE-T1WI) during 3h-72h in a 1.5T Siemens MAGNETON Avanto Scanner. Lesion volumes were analyzed in a blinded and randomized manner. Triphenyltetrazolium chloride (TTC), Nissl, and Evans Blue stainings were performed at the corresponding sections.

RESULTS

Increased lesion volumes derived from T2WI, DWI, ADC, CE-T1WI, and TTC all were noted at 3h and peaked at 24h-48h after MCAO injury. TTC-derived infarct volumes were not significantly different from the T2WI, DWI-, and CE-T1WI-derived lesion volumes at the last imaging time (72h) point except for significantly smaller ADC lesions in the MCAO model (P<0.05). Volumetric calculation based on TTC-derived infarct also correlated significantly stronger to volumetric calculation based on last imaging time point derived on T2WI, DWI or CE-T1WI than ADC (P<0.05). At the last imaging time point, a significant increase in Evans Blue extravasation and a significant decrease in Nissl-positive cells numbers were noted in the vehicle-treated MCAO injured animals. The lesion volumes derived from T2WI, DWI, CE-T1WI, and Evans blue extravasation as well as the reduced numbers of Nissl-positive cells were all significantly attenuated in the agmatine-treated rats compared with the control ischemia rats (P<0.05).

CONCLUSION

Our results suggest that agmatine has neuroprotective effects against brain edema on a reperfusion model after transient cerebral ischemia.

Assessing the chronic neuropsychologic sequelae of human immunodeficiency virus-negative cryptococcal meningitis by using diffusion tensor imaging

BACKGROUND AND PURPOSE

The high rate of neuropsychologic sequelae in CM survivors indicates that initial antifungal therapy is far from being satisfactory. This prospective cross-sectional study applied DTI on HIV-negative CM patients to determine whether microstructural changes in brain tissue are associated with subsequent cognitive symptoms.

MATERIALS AND METHODS

Fifteen patients with HIV-negative CM and 15 sex- and age-matched healthy volunteers were evaluated and compared. All underwent complete medical and neurologic examinations and neuropsychologic testing. Brain DTI was obtained to derive the FA and ADC of several brain regions. Correlations among DTI parameters, neuropsychologic rating scores, and cryptococcal-antigen titer in CSF were analyzed.

RESULTS

Significant ADC values increased and FA values decreased in HIV-negative CM patients in multiple selected regions of interest, including the genus of the corpus callosum and the frontal, parietal, orbito-frontal, and periventricular white matter and lentiform nucleus. Higher CSF cryptococcal-antigen titer on admission was associated with poorer DTI parameters (r = -0.666, P = .018), which were linearly related to worse cognitive performance during follow-up.

CONCLUSIONS

The decline in brain DTI parameters in the associated brain areas indicates an HIV-negative CM microstructural pathology that is related to neuropsychologic consequences.

Interleukin-20 promotes angiogenesis in a direct and indirect manner

IL-20 belongs to the IL-10 family and is involved in the pathogenesis of keratinocyte hyperproliferation in vivo. Endothelial cells express IL-20 receptors. To explore the function of IL-20 on endothelial cells, we treated human umbilical vein endothelial cells (HUVECs) and human microvascular endothelial cells (HMECs) with human IL-20 and analyzed its effect on endothelial cells. IL-20 induced proliferation of endothelial cells and the activity was specifically blocked by anti-human-IL-20 monoclonal antibody and soluble (s)IL-20 receptor (R)1 and sIL-20R2. An alternatively spliced variant of IL-20 was isolated and also was shown to induce proliferation of HUVECs and HMECs. Treatment of HUVECs with both IL-10 and IL-20 demonstrated that IL-10 antagonized the activity of IL-20 because it diminished IL-20-induced proliferation of HUVECs. IL-20 significantly induced HUVECs migration and vascular tube formation on Matrigel in vitro. In vivo, IL-20 also enhanced tumor angiogenesis. Incubation of IL-20 with HUVECs induced transcripts of bFGF, VEGF, MMP-2, MMP-9, and IL-8. Furthermore, incubation of HUVECs with IL-20 induced phosphorylation of ERK1/2, p38, and JNK. Thus, IL-20 is a pleiotropic cytokine and promotes angiogenesis.

Clinical value of CYFRA21-1, NSE, CA15-3, CA19-9 and CA125 assay in the elderly patients with pleural effusions

The aim of this study was to evaluate the individual and combined diagnostic value of five tumour markers in the elderly patients with pleural effusions. Serum and pleural fluid levels of cytokeratin fragment 19 (CYFRA21-1), neuron-specific enolase (NSE), carbohydrate antigen 15-3 (CA15-3), carbohydrate antigen 19-9 (CA19-9) and carbohydrate antigen 125 (CA125) were assayed in 32 elderly patients with malignant pleural effusions resulting from advanced lung cancer and in 30 elderly patients with benign pleural effusions by ELISA. Serum levels of CYFRA21-1, NSE, CA15-3, CA19-9 and CA125 in patients with malignant pleural effusions were 12.84 +/- 6.48 microg/l, 22.07 +/- 11.25 microg/l, 65.74 +/- 30.26 kU/l, 56.32 +/- 25.6 kU/l and 71.86 +/- 31.45 kU/l, respectively, and were significantly higher than those in patients with benign pleural effusions (p < 0.01). Pleural fluid levels of CYFRA21-1, CA15-3, CA19-9 and CA125 except NSE in patients with malignant pleural effusions were 18.64 +/- 8.15 microg/l, 59.31 +/- 27.35 kU/l, 48.24 +/- 21.56 kU/l and 62.16 +/- 27.79 kU/l, respectively, and were significantly higher than those in patients with benign pleural effusions (p < 0.01). The parallel combined testing of five tumour markers in serum increased the diagnostic sensitivity to 90.6%, and serial combined testing increased the diagnostic specificity to 93.3%. The sensitivity (%) and specificity (%) of these tumour markers in pleural fluid were as follows: CYFRA21-1, 84.4/90; CA15-3, 62.5/73.3; CA19-9, 37.5/66.7; CA125, 56.3/70; for differentiating malignant effusions from benign effusions. When CYFRA21-1 and CA15-3 combined, the sensitivity and specificity were increased (100% and 90% respectively). Serum and pleural fluid levels of the five tumour markers shows certain values in the diagnosis and differentiate diagnosis for malignant pleural effusions in the elderly patients from benign. The combined assay of five tumour markers in serum and the CYFRA21-1 combined with CA15-3 in pleural fluid were helpful and can increase the sensitivity and specificity in diagnosing malignant pleural effusions.

Successful outpatient treatment of renal vein thrombosis by low-molecular weight heparins in 3 patients with nephrotic syndrome

Renal vein thrombosis (RV Thromb) is a serious complication ofnephrotic syndrome. Anticoagulation is usually recommended as the treatment of choice. This study reports 3 nephrotic patients diagnosed to have RVThromb combined with thromboembolic events. Low-molecular weight heparin (LMWHep) was given subcutaneously every 12 hours following the diagnosis of RVTromb, which continued at the outpatient clinic after an average of 11 in-hospital days. The patients visited the nephrology outpatient clinic every other week and underwent magnetic resonance image (MRI) studies at 6-week intervals for follow-up of patency of the involved renal vein. LMWHep was discontinued when MRI showed this patency. The average outpatient treatment period was 74 days. There was no recurrent RVThromb in the follow-up course of 6 months after discontinuation of LMWHep. Kidney function was preserved, as indicated by image studies and serial renal function tests. LMWHep produced a more predictable anti-coagulant effect, a superior bioavailability, a longer half-life and a dose-independent effect than unfractionated heparin and coumadin. These benefits made the outpatient treatment of RVThromb possible. Our report recommends outpatient treatment of RVThromb by LMWHep because it is feasible, effective and safe.

Surgical treatment for upper or middle esophageal carcinoma occurring after gastrectomy: a study of 52 cases

Fifty-two patients presenting with upper or middle esophageal carcinoma after gastrectomy between 1980 and 2003 were analyzed retrospectively. Among them, there were five cases of total gastrectomy, six cases of proximal partial gastrectomy and 41 cases of distal subtotal gastrectomy. The interval between gastrectomy and the diagnosis of esophageal carcinoma ranged from 2 to 22 years. Surgical procedures included resection of the esophageal lesion with esophageal replacement using non-reversed or reversed gastric tubes (2 and 3 cases respectively), and short or long segment colon (5 and 40 cases respectively); two cases underwent a palliative procedure (jejunostomy). Complications included cervical anastomotic leaks (3 cases), pulmonary infection (3 cases), atelectasis (2 cases) and cordis arrhythmia (5 cases), all of which responded to treatment. In our group, resection of the esophageal lesions and reconstruction of the esophagus was performed in 45 cases (86.5%), exclusion and bypass procedure of esophageal carcinoma and following radiotherapy and chemotherapy in four (7.7%), eternal jejunostomy for intestinal nutrition in two (3.9%) and death occurred in one case (1.9%) due to multiple organ dysfunction syndrome (MODS). Esophageal resection combined with lymph node dissection is indicated for the treatment of upper or middle esophageal carcinoma following gastrectomy. While esophageal substitutes can include non-reversed or reversed gastric tubes as well as short or long segment colon interpositions, we usually recommend the use of colon interposition. The 1-, 3- and 5-year survival rate of cases with resection of the esophageal lesions and reconstruction of the esophagus was 84.6%, 57.7% and 26.7% respectively.

Prognostic factors and therapeutic outcome of isolated symptomatic middle cerebral artery stenosis

To analyze the prognostic factors and therapeutic outcome of adult patients with isolated symptomatic stenosis of the middle cerebral artery (MCA). Forty-nine patients were retrospectively verified with isolated symptomatic stenosis of the MCA through both magnetic resonance angiogram and transcranial color-coded duplex sonography. Therapeutic outcome at 1 year or more was determined using a modified Barthel index (BI). For the purpose of analysis, the patients were divided into two groups: a good outcome group (BI > or = 12) and a poor outcome group (BI < 12 or recurrent stroke). The association between different therapeutic regimens and the percent free of recurrent stroke after the first event of cerebral infarction was assessed with Kaplan-Meier plots compared by a log-rank test. These patients accounted for 2.8% of all patients with the first event of cerebral infarction during the same period. At follow-up of 1 year or more, 63% had good outcomes whilst the other 37% had poor outcomes. Overall, 26.5% suffered from recurrent strokes during the follow-up period. According to the statistical analysis, the stepwise logistic regression revealed that only the National Institutes of Health Stroke Scale (NIHSS) at the time of admission was independently associated with a poor outcome. Furthermore, Kaplan-Meier analysis showed a significantly higher percentage of patients free of recurrent stroke events amongst those who were treated with warfarin. The NIHSS at the time of admission was a predictor of outcome amongst our patients, and stenosis of the MCA implies the danger of recurrent cerebral events. Our study also demonstrates the efficacy of oral anticoagulants in the secondary prevention in this specific group of patients. Therefore, we look forward to more prospective multicenter investigations in evaluating the efficiency of therapy in the future.

Data management using the personal digital assistant in an acute pain service

Handheld personal digital assistants (PDA) are increasingly being used by physicians for a variety of information and data management purposes. We evaluated a PDA-based data management system for our acute pain service. A structured questionnaire survey was conducted to assess staff experience and attitude towards the paper system before the introduction of the PDA, and three months after introduction of the PDA system. We compared the time taken to conduct the acute pain round before and after the implementation of the PDA. The time saved in data management and the amount of paper saved were estimated. Data from 177 patients with a total of 635 acute pain follow-up visits were entered over a three-month period. User satisfaction, ease of access to drug reference and clinical guidelines were similar between the two systems. The respondents found that the PDA was easy to use but less so than the paper system (P = 0.007), in particular, when accessing a patient's cumulative data (P = 0.007). There was no missed follow-up or data entry with the use of PDA. The time taken to attend follow-up visits was similar for the two systems (Paper: 8.8 +/- 3.2 compared to PDA: 7.0 +/- 2.0 minutes, P = 0.151). The estimated annual amount of paper and time saved in data management was 650 sheets and 130 man-hours respectively. Our experience with the use of the PDA in APS was satisfactory. The PDA system can potentially reduce time and paper use and missed data entry and patient follow-up.

Guillain-Barré syndrome in southern Taiwan: clinical features, prognostic factors and therapeutic outcomes

To determine the clinical features, prognostic factors, and therapeutic results of Guillain-Barré syndrome (GBS) in order to improve the therapeutic strategy for this disease. We retrospectively reviewed the electrodiagnostic study and medical records of patients with GBS admitted to Chang Gung Memorial Hospital, Kaohsiung, between January 1986 and December 2000. Outcomes and prognosis were followed-up after 1 year. Ninety-six patients were enrolled in this study. According to the clinical and electrophysiological findings, 77 patients were acute inflammatory demyelinating polyradiculoneuropathy, seven were Miller Fisher syndrome, and six were axonal forms, and six were unclassified. At a follow-up of 1 year, 61 patients (64%) recovered, 30 (31%) had residua and five (5%) died. Amongst these 30 had residua, including unassisted gait in 19, assisted gait in four, and wheel/bed bound in seven. According to the statistical analysis, disabilities at the nadir (P < 0.0001) and at admission (P = 0.014) were significant prognostic factors. Variables used for the stepwise logistic regression, and the results revealed that after analysis for all the above variables, only disability at the nadir (P < 0.0001) was independently associated with the treatment failure rate. Our study revealed 27% of cases in need of respiratory support during hospitalization, and 5% of hospital-treated patients die from the complications. Furthermore, 31% had residua at a follow-up of 1 year or more. If prognostic factors are considered, disability at the nadir during hospitalization demonstrates consistently poor therapeutic outcomes. Therefore, early diagnosis, choice of appropriate treatment, and preventing complications during acute stages are essential to maximize the potential for survival.

Cerebral infarction in perinatal and childhood bacterial meningitis

BACKGROUND

Cerebral infarction is an important neurological complication of childhood bacterial meningitis, but little is known about its epidemiology and outcomes.

AIM

To determine the predictive factors, clinical features, causative pathogens, and outcomes of cerebral infarction secondary to perinatal and childhood bacterial meningitis.

DESIGN

Retrospective analysis

METHODS

Over the period 1986-2001, 166 perinatal and childhood patients were identified as having culture-proven bacterial meningitis, of whom 14 had cerebral infarction at admission. The clinical and CSF data of patients with and without cerebral infarctions on admission were compared.

RESULTS

Cerebral infarction patients accounted for 10% (14/166) of bacterial meningitis cases, mostly in the first year of life (11/14, 79%). Salmonella species (n = 4) and Streptococcus pneumoniae (n = 4) were the most frequent causative pathogens, accounting for 57% (8/14) of episodes. Single infarctions were found in four patients and multiple infarctions in 10. At 1 year follow-up, outcome was good in three, but poor in 11. Significant differences between the two patient groups at admission included age bands, presence of seizures, hydrocephalus, disturbed consciousness on admission, and CSF lactate concentration.

DISCUSSION

There was a high prevalence of cerebral infarctions when the disease was caused by S. pneumoniae and Salmonella species. Occurrence was highest in the first year of life, and the prognosis in this patient group is poor. Risk factors associated with cerebral infarction in our patients included age 28-365 days, seizures, hydrocephalus, disturbed consciousness on admission, and high CSF lactate concentrations.

Biomechanical comparison of posterior cervical fixation

STUDY DESIGN

Biomechanical stability using four different posterior cervical fixation techniques was evaluated in human cadaveric spine.

OBJECTIVES

To introduce an alternative interspinous fixation technique using wavy-shaped rods, and to compare its in vitro biomechanical stability with that of other posterior cervical fixation techniques.

SUMMARY OF BACKGROUND DATA

Fixation of the posterior cervical spine with interspinous wiring is well known as Rogers' or Bohlman's technique. Recently, several plate fixation techniques have been used for posterior cervical stabilization. Since 1983, the authors have developed the wavy-shaped rod system as an alternative to the interspinous fixation technique. This unique technique has been proven clinically useful in Japan. However, the authors are not aware of any prior biomechanical studies.

METHODS

Seven fresh frozen cervical human spines were tested at the C5-C6 motion segment. Nondestructive static biomechanical testing was performed with flexion-extension, lateral bending, and axial rotation for the following stabilization techniques: intact spine, creation of a Stage 3 distractive-flexion injury followed by fixation with the wavy-shaped rods bounded by three multistrand cables, interspinous wiring with a multistrand cable, triple wiring technique using multistrand cables with a pair of unicortical grafts from the ilium, and lateral mass plate fixation with Magerl's screw technique. Testing was performed on a material testing machine (MTS 858 Bionix test system, MTS, Minneapolis, MN), and load displacement curves were obtained using four linear extensometers and one rotatory extensometer across the C5-C6 motion segment.

RESULTS

In axial compression loading, the reconstructed specimens showed significant differences in range of motion measured at the anterior and posterior positions, and statistical analysis was performed using one-way analysis of variance. In a comparison of the four fixation techniques, the construct with the wavy-shaped rod indicated significantly less motion both anteriorly and posteriorly than with the other fixation techniques. Also in flexion-extension loading, all the techniques significantly limited the intervertebral motion below the level of the intact motion segment. Particularly, the construct with the wavy-shaped rod showed the smallest mobility, 49.9% anteriorly and 9.3% posteriorly, compared with that of the intact spine. In lateral bending, the lateral mass plate provided the greatest stability, which was superior to the intact segment, but the difference was not statistically significant. In axial rotation, all the reconstruction techniques limited the angular motion below the intact level (wavy rod, 68.0%; Rogers' wiring, 75.2%; Bohlman's triple wiring, 59.8%; lateral mass plate, 71.7%), but no significant differences were observed using one-way analysis of variance, as compared with the intact segment.

CONCLUSIONS

All four reconstruction techniques restored the stability of the cervical motion segment to at least the level of the intact motion segment before destabilization. An alternative cervical posterior fixation technique, the Wavy Rod system, was considered the most effective technique in stabilizing a cervical motion segment, particularly in axial compression and flexion extension loading.

Multilaminate resorbable biomedical device under biaxial loading

The design and test of a multilaminate sheet developed for a hernia repair application is presented. As biomaterial applications become more complex, characterization of uniaxial properties becomes insufficient and biaxial testing becomes necessary. A measure of the in-plane biaxial strength of the device is inferred from a ball burst test. The results of this test for different thicknesses of the device are correlated with the uniaxial strength of the material. A biaxial test such as the ball burst test is more indicative of the properties of a planar material than would be a uniaxial test. The interactions in the biaxial mode of failure are of value and can be related back to a classical uniaxial tensile test from the ball burst test. The material used in this study to fabricate the device was a resorbable biomaterial called small intestinal submucosa (SIS). The effects of rehydration on the stiffness and associated ball burst properties of the SIS device were also measured. It is shown that at a rehydration time of 5 min from a reference dry state, steady-state mechanical properties are reached.

Biomechanical evaluation of translaminar facet joint fixation. A comparative study of poly-L-lactide pins, screws, and pedicle fixation

STUDY DESIGN

Nine sheep cadaveric spines were used in this acute postoperative model.

OBJECTIVES

To compare the biomechanical performance of translaminar facet joint fixation techique with that of cortical screws and bioabsorbable poly-L-lactide pins and with that of rigid pedicle screw fixation in the lumbar spine.

SUMMARY OF BACKGROUND DATA

Among numerous posterior spine fixation techniques, pedicle screw fixation has been reported to be the most rigid construct and to provide high fusion rate. Translaminar facet joint screw fixation is an alternative to pedicle screw fixation and is the lowest profile construct that achieves stabilization. The authors have developed a new concept involving application of bioabsorbable poly-L-lactide pins to translaminar facet joint fixation. Degradation in the stiffness of the implants with time may be advantageous for fusion mass remodeling.

METHODS

A total of nine sheep L2-L6 cadaveric spines were used. Each intact spine was nondestructively tested in flexion-extension bending (+/- 5-Nm peak bending moment with 100-N axial compression) on a modified testing machine. Loads were applied for 10-second periods using sinusoid waveforms. After testing the intact spine, bilateral fenestration was performed between L4 and L5 and the medial aspect of the facet capsule was resected. The L4-L5 functional spinal unit was than stabilized by five methods: translaminar facet joint fixation with smooth poly-L-lactide pins; translaminar facet joint fixation with cortical screws; pedicle screw fixation with the Texas Scottish Rite Hospital system; and without instrumentation, in that order. Linear displacement of L4 inferior and L5 superior articular processes in the sagittal plain (delta facet) and L4-L5 intervertebral rotation in the sagittal plain (theta sagittal) were measured by the extensometers mounted to the spine. Ranges of motion (delta facet and theta sagittal), neutral zones, linear elastic zone stiffness, and the total energy absorption during the load-unload cycle (hysteresis) were calculated.

RESULTS

By resecting the facet joint capsules and ligamentum flavum, delta facet and theta sagittal were not increased significantly, whereas the increase of neutral zones and hysteresis were statistically significant. Compared with the intact spine, delta facet was significantly reduced to 41% of normal with translaminar facet joint fixation with poly-L-lactide pins, to 9% with translaminar facet joint fixation with screws, and to 11% with the Texas Scottish Rite Hospital system. Neutral zones of delta facet showed a similar pattern, and these differences were significant. Regarding linear elastic zone stiffness, translaminar facet joint fixation with screws provided a stiffer construct than did pedicle screw fixation in the flexion loading mode, whereas pedicle screw fixation yielded higher values for stiffness in extension loading. Translaminar facet joint fixation with poly-L-lactide pins increased linear elastic zone stiffness in extension loading, but the increase was less than was achieved with the other constructs.

CONCLUSIONS

The facet joint is the only true articulation in the lumbosacral spine. It is logical to fix this part directly to achieve spine fixation. Translaminar facet joint fixation with screws show similar biomechanical performance to pedicle screw fixation. Translaminar facet joint fixation with poly-L-lactide pins is significantly less stiff than either type of screw fixation, but it also restricts the facet joint and intervertebral motions significantly when compared with the intact spine.

[Observation of therapeutic effect by combined administration of Salvia miltiorrhiza, ligustrazine and Panax notoginseng on late hemorrhagic shock of rabbits]

OBJECTIVE

To explore the therapeutic mechanism of Salvia miltiorrhize, ligustrazine and Panax notoginseng in treating late hemorrhagic shock in rabbit.

METHODS

Rabbit hemorrhagic shock models (MPA 5.3 kPa) were set up according to Wiggers' method and administrated Salvia miltiorrhiza, ligustrazine, Panax notoginseng. The values of blood RBC superoxide dismutase (SOD) and blood lactate (BL), plasma malondialdehyde (MDA) and magnesium (Mg++) were continuously monitored before shock, 120 minutes after shock, 60 and 120 minutes after hydraulic dilatation.

RESULTS

(1) In 120 minutes after shock, the level of SOD decreased and the concentrations of MDA, BL, Mg++ were markedly increased, which indicated that the cell membrane damage caused by oxygen free radicals in rabbit hemorrhagic shock. (2) Salvia miltiorrhiza, Ligustrazine or Panax notoginseng could alleviate lipidperoxidation injury to tissue. Compared with the single drug administration groups, the effects of oxygen free radicals scavangers by combined administration with half dose of 2 drugs were better than the single drug with full dose alone and the side effects such as depression of blood pressure and heart rates would be alleviated.

CONCLUSION

Combined administration of Salvia miltiorrhiza, ligustrazine and Panax notoginseng would half the dosage, the blood pressure depression and heart rate reduction alleviated and better result obtained.

Animal study of phoenix total artificial heart implantation

BACKGROUND

It is well accepted that a total artificial heart (TAH) can be used as a bridge to heart transplantation during the waiting period for organ donation. A series of combined studies, conducted by the Kaohsiung Veterans General Hospital, National Yang-Ming Medical College and Municipal Tainan Hospital, has been performed to improve the Phoenix artificial heart developed by Dr. Kevin Kuo-Tsai Cheng.

METHODS

In growing calves (weighed about 80 kg), standard procedures were used to remove the hearts and replace them with the TAHs. Records were made of hemodynamic data, physiological responses, blood biochemistry data and physical activities after operation and until the death of the calves. Finally, autopsies were used to determine the causes of death.

RESULTS

A total of 23 calves were studied. Twenty-two of them survived 1 to 12 days, or an average 4.95 days. One survived more than 30 days. All the calves could breathe, stand, eat and void by themselves two hours after operation. Respiratory failure was the major cause of death.

CONCLUSIONS

No thrombus within the TAH was noted in the last five cases, meaning that turbulent flow or dead space of the TAH was improved. Better intensive care and prevention of infection will be the next challenge for long-term use of TAH.

Colon replacement from esophagus. Clinical experience from 240 cases

The clinical experience in the colon replacement of the esophagus in 240 cases is reported. The overall operative morbidity was 17.5%; the incidence of the anastomotic leaks was 10.4%; and the mortality was 2.80%. The points in surgical technique were: 1) utilizing the left colic artery as the supporting vessel if possible, based on the anatomy of the colon vessel; 2) using the colon segment in an isoperistaltic position, which has been proved much physiological; 3) single-layer anastomosis which is simple and reliable, with minimal inflammation and quick healing; and 4) choosing the channel of the colon transplant according to the disease condition, the age, and the function of the heart and the lung of the patients.

Right gastroepiploic artery: an alternative arterial conduit for coronary artery bypass

From September 1990 to February 1991, 15 cases of myocardial revascularization with the right gastroepiploic artery (RGEA) combined with arterial or venous grafts were performed at VGH-Taipei. All were males, ranging in age from 49 to 64 years (mean age 61.2 +/- 4.6 years). The mean number of distal anastmoses including vein grafts was 3.6 +/- 0.7 and the mean number of graft was 3.1 +/- 0.3 per patient. The mean aortic clamp time was 123.6 +/- 24.0 minutes and the mean cardiopulmonary bypass time was 176 +/- 35 minutes. There was one mortality (6.7%). The other 14 patients are alive without angina. Studied within 3 postoperative months, graft early patency was 100% (6/6) in GEA graft. GEA graft should be a third available arterial conduit for coronary artery bypass.

A new autoperfusion technique for aortic reconstruction of suprarenal aortic aneurysm

Visceral ischemia is a serious factor in the postoperative morbidity and mortality of suprarenal aortic reconstruction. We reported two patients of suprarenal aortic aneurysm involving visceral arteries, who received successful Dacron graft replacement by using Pruitt-Inahara balloon catheters as an autoperfusion for preservation of the visceral organs. No visceral organ ischemia occurred postoperatively except in patient 2 who had preoperative chronic renal failure and persistent renal failure after the operation. The renal function recovered gradually during the follow-up period. Both patients are doing well at the present time. The new autoperfusion technique can directly deliver normothermic blood from the arterial cannula at proximal aorta to the individual visceral arteries by using the balloon perfusion catheters. It is simple, safe, easily instituted and the used products are readily obtainable. It allows the surgeon to provide an effective protection of visceral organs for the suprarenal aortic reconstruction.

[Emergency lung resection in patients with massive hemoptysis]

Emergency lung resection was done in 32 patients with massive hemoptysis. The morbidity and mortality rates were 18.75% and 6.25% respectively. Problems about how to find the focus of hemoptysis, when to perform the operation, how to select anaesthesia, operative techniques and limits of lung resection were discussed.

[Early pericardiectomy of acute purulent pericarditis]

The results of early pericardiectomy in 15 cases of acute purulent pericarditis were reported. 13 cases were followed up from 2 to 8 years, none of them developed chronic constrictive pericarditis. The operation is simple and can shorten the time of hospitalization following thorough debridement of the infected foci.

Experimental study and clinical application of a single-row suturing esophagogastrostomy

A single-row suturing anastomosis (SRA) for an esophagogastrostomy was experimentally investigated in dogs. SRA not only shortened operating time, but also led to better pathological results when compared with double-row suturing anastomosis. Wide-brim suturing and equal distance between the sutures, providing increased and well-distributed blood circulation, are the key points for success of SRA. Its simplicity and safety are advantages of SRA as has been shown in 90 cases in clinical application.

[Clinical study of colic vessels with respect to their significance in the replacement of the esophagus by the colon]

In 162 cases of esophageal replacement by colon we observed the configuration, distribution and pulsation of the middle, left, right and marginal colic arteries. Observation showed that the middle colic artery had only one major stem in 120 cases, 2-4 branches in 37 cases, and was absent in 5 cases. The middle colic artery originated from the superior mesenteric artery in 126 cases, had one stem originating from the superior mesenteric artery and another from the right colic artery in 10 cases. The middle and the right colic arteries forming one stem and originating from the superior mesenteric artery were seen in 21 cases. The distributive patterns of the middle colic arteries showing "T" type was seen in 37 cases, "V" type in 28 cases, and multiple paralleled branches in 9 cases. Vascular anastomoses between the ascending branch of the left colic artery and the middle colic artery were available in 157 cases (97%), 12 cases with the arc of Riolan. The nearest distance between the marginal artery and the colic wall was at the splenic flexure. The origin of the right colic artery varied greatly and its distributive area was small. We advocated the use of the ascending branch of the left colic artery for blood supply and the transverse colon for replacement of the esophagus in an isoperistaltic fashion (131/162 cases) to be the procedure of choice.