Preemptive analgesia for postoperative pain relief in lumbosacral spine surgeries: a randomized controlled trial.

BACKGROUND CONTEXT: Administration of analgesic medication, before the actual onset of painful stimulus, is more effective than that after the onset of painful stimulus. This is the principle of preemptive analgesia. Although it is often considered superior to other forms of analgesia, its role in postoperative pain relief after lumbosacral spinal surgery has not been fully investigated. PURPOSE: To analyze the efficacy of preemptive analgesia with a single caudal epidural injection for patients undergoing surgeries on the lumbosacral spine by the posterior approach. STUDY DESIGN/SETTING: Randomized, double-blinded and controlled clinical trial. PATIENT SAMPLE: Eighty-two patients who underwent discectomy in the lumbosacral spine by the posterior approach, with or without instrumentation, were randomized to the control group (n=40) and to the study group (n=42). METHODS: Patients in control group received a single caudal epidural injection of 20 ml of normal saline. Patients in study group received a single caudal epidural injection of 20 ml containing bupivacaine and tramadol as the active agents. The time interval between this injection and the surgical incision was never less than 20 minutes in either of the groups. This facilitated enough time for the drug to get fixed to the nerve roots, leading to effective preemptive analgesia. OUTCOME MEASURES: Patients were monitored for postoperative pain immediately after surgery when they had completely recovered and regained consciousness from general anesthesia, and subsequently 4, 8, 12 and 24 hours thereafter. Pain was quantified using the visual analog scale (VAS) and the verbal rating scale (VRS). The time at which supplemental analgesic medication was first demanded in the postoperative period by the patient was also noted. RESULTS: The two groups were comparable for age, sex, body weight and the type of surgery they underwent. Because the data did not have a normal Gaussian distribution, the one-tailed Mann-Whitney test, being a nonparametric test, was adopted for statistical analysis. Accordingly, VAS and VRS values at all time intervals were significantly lower (p<.0001) in the study group as compared with the control group. This indicated significantly better pain relief in the study group. There was also a significant delay (p=.0041) in the first demand for supplemental analgesic medication in the postoperative period in the study group. No complication specific to the procedure was noted except for the development of postoperative urinary retention, which was transient and appropriately managed with urinary catheterization. CONCLUSIONS: Preemptive analgesia with a single caudal epidural injection of bupivacaine and tramadol is a safe, simple and effective method for postoperative pain relief.     

Acute impairment of regional myocardial glucose uptake in the apical ballooning (takotsubo) syndrome

BACKGROUND: Apical ballooning syndrome (ABS) is a poorly understood clinical entity characterized by acute, transient systolic dysfunction of the left ventricular (LV) apex in the absence of epicardial coronary artery disease and commonly associated with acute emotional stress. We report abnormal regional myocardial perfusion and glucose uptake in 4 consecutive ABS patients studied using positron emission tomography with 13N-ammonia and 18F-fluorodeoxyglucose within 72 hours of presentation with ABS. METHODS: All patients were postmenopausal females, 3 of whom had a major recent life stress event. Coronary angiography revealed no or minimal obstructive epicardial coronary artery disease. All patients exhibited reduced glucose uptake in the mid-LV and apical myocardial segments, which was out of proportion to perfusion abnormalities in half of the cases. CONCLUSION: In all 4 patients, affected regions subsequently recovered regional LV systolic function within 6 weeks.     

Carotid Stent-Supported Angioplasty via Radiobrachial Route

Endovascular stent-supported angioplasty is a treatment option for atherosclerotic disease of the cervical internal carotid artery in high-risk patients. The traditional transfemoral approach is not suitable for patients who suffer from common femoral artery or abdominal aorta atheropathy. We report a case of carotid stent deployment using the radial route in a 68-year-old man with type B aortic dissection, having severe right internal carotid artery origin stenosis, presenting with ipsilateral retinal ischemic events. Technical aspects of carotid stenting via the radial approach are described and the related literature is discussed.     

An adenovirus type 5 (AdV5) vector encoding an envelope domain III-based tetravalent antigen elicits immune responses against all four dengue viruses in the presence of prior AdV5 immunity

Dengue is a mosquito-borne viral disease caused by four antigenically distinct serotypes of dengue viruses (DENVs). This disease, which is prevalent in over a hundred tropical and sub-tropical countries of the world, represents a significant global public health problem. A tetravalent dengue vaccine capable of protecting against all four DENV serotypes has been elusive so far. Current efforts are focused on producing a tetravalent vaccine by mixing four monovalent vaccine components. In this work, we have utilized a discrete carboxy-terminal region of the major DENV envelope (E) protein, known as domain III (EDIII), which mediates virus entry into target cells and contains multiple serotype-specific neutralizing epitopes, to create a chimeric tetravalent antigen. This antigen derived by in-frame fusion of the EDIII-encoding sequences of the four DENV serotypes was expressed using a replication-defective recombinant human adenovirus type 5 (rAdV5) vaccine vector. This rAdV5 vector induced cell-mediated immune responses and virus-neutralizing antibodies specific to each of the four DENVs in mice. Interestingly, anti-AdV5 antibodies did not suppress the induction of DENV-specific neutralizing antibodies. We observed that anti-AdV5 antibodies in the sera of immunized mice could promote uptake of a rAdV5-derived reporter vector into U937 cells, suggesting that pre-existing immunity to AdV5 may in fact facilitate the uptake of rAdV5 vectored vaccines into antigen presenting cells. This work presents an alternative approach to developing a single component tetravalent vaccine that bypasses the complexities inherent in the currently adopted four-in-one physical mixture approach.     

Recrudescent Tobacco Exposure Following Heart Transplantation: Clinical Profiles and Relationship with Athero-Thrombosis Risk Markers

To identify tobacco recidivism among 86 heart transplant recipients who were smokers but demonstrated compliance with a smoking cessation program pre-transplant, we used a questionnaire and randomly tested urine for nicotine and its by-products. In 36 patients, we also evaluated circulating levels of HS-CRP, homocysteine and MPV. Twenty-eight (32.5%) of 86 patients met our definition for tobacco exposure. In this cohort, 28 (32.5%) of 86 patients met our definition for tobacco exposure. Of these 28, 12 patients self-reported tobacco use and demonstrated biochemical verification; 14 patients demonstrated only biochemical evidence of significant tobacco exposure; 2 patients self-reported tobacco use but did not demonstrate biochemical positivity. Smoking cessation within 6 months of transplantation (r = 0.52) and time post-transplantation (r = 0.43) were independent predictors for recidivism of tobacco use, p < 0.01. No differences in HS-CRP, homocysteine and MPV levels were noted among the groups. Our investigation demonstrates a high rate of tobacco recidivism among heart transplant recipients, yet few admit to it. The adverse effects of tobacco do not appear to be directly modulated by an effect on athero-thrombotic risk markers.     

Protection against 7,12-dimethylbenzanthracene-induced tumour initiation by protein A in mouse skin.

Protein A is an immunostimulating glycoprotein obtained from Staphylococcus aureus Cowan I. Its antitumour activity is proven in various tumour models. Its ability to provide protection against tumour initiation by the chemical carcinogen 7,12-dimethylbenzanthracene (DMBA) has been investigated in the present study using a mouse skin model of two-stage carcinogenesis. Protein A was administered intraperitoneally (1 microgram/animal 20 g body wt.) twice a week for 2 weeks, prior to initiation by DMBA. The promotion was performed by twice weekly applications of 12-O-tetradecanoyl phorbol-13-acetate (TPA) (3 or 5 micrograms/animal in 100 microliters acetone). Protein A provided significant protection to animals from DMBA-induced tumour initiation as was observed by the decrease in cumulative number of tumours, percent of animals developing tumours, number of tumours per animal and rate of tumour growth. Our data indicate that protein A has anticarcinogenic properties.     

Effects of MR imaging on murine natural killer cell cytotoxicity

To determine the effect of MR imaging on the immune system, 21 male C57BL/6 X DBA/2 F1 mice were exposed to MR imaging at a field strength of 0.15 T for 2 hr. Another nine mice (controls) were sham exposed for the same amount of time. Mice were sacrificed and their spleens removed 24, 72, and 144 hr after the exposure (MR or sham). Spleen cell suspensions were passed over nylon wool columns and then used as effector cells in a short-term natural killer cell cytotoxicity assay with 51Cr-labeled YAC-1 cells as target cells. The results showed no evidence of decreased cytotoxicity due to exposure to MR. On the contrary, at all three times after exposure and for all target-to-effector cell ratios, mean cytotoxicity was greater for MR-exposed groups than for sham-exposed groups. The results show that MR exposure has no adverse effect on the immune system, as evidenced by natural killer cell activity.