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991.

Background

Opioid analgesics have been a standard modality for postoperative pain management after total knee arthroplasty (TKA) but are also associated with increased risk of nausea, pruritus, vomiting, respiratory depression, prolonged ileus, and cognitive dysfunction. There is still a need for a method of anesthesia that can deliver effective long-term postoperative pain relief without incurring the high cost and health burden of opioids and nerve blocks.

Questions/purposes

(1) Is liposomal bupivacaine-based periarticular injection (PAI) more effective than morphine-based spinal anesthesia or ropivacaine-based PAI in controlling postoperative pain after TKA? (2) Do patients treated with liposomal bupivacaine-based PAI experience fewer opioid-related adverse events compared with patients treated with morphine-based spinal anesthesia or ropivacaine-based PAI in controlling postoperative pain after TKA?

Methods

This multicenter, blind trial randomized 119 patients undergoing TKA with spinal anesthesia to receive spinal anesthesia plus periarticular injection with liposomal bupivacaine (40 patients), spinal anesthesia with bupivacaine plus intrathecal morphine (41 patients) but no liposomal bupivacaine injection, or spinal anesthesia with bupivacaine (38 patients) and no liposomal bupivacaine injection. The two groups that did not receive periarticular liposomal bupivacaine did receive periarticular injection with ropivacaine, and all three groups had ketorolac (30 mg) plus epinephrine (1:1000) in the periarticular injections. Patients in all three groups received identical perioperative multimodal analgesic and antiemetic drugs. All patients were analyzed in the group to which they were randomized and no patients were lost to followup. The primary study endpoints were visual analog score (VAS) for pain and narcotic use during postoperative day 1. Secondary endpoints included side effects associated with narcotic administration during the hospital stay.

Results

Mean VAS pain in the liposomal bupivacaine PAI group was lower than that for the ropivacaine PAI group at 6 hours (1.8 ± 2.1 versus 3.3 ± 2.3, p = 0.005, mean difference: 1.5, 95% confidence interval [CI], 0.5–2.5) and 12 hours (1.5 ± 2.0 versus 3.3 ± 2.4, p < 0.001, mean difference: 1.8, 95% CI, 0.8–2.8) after surgery. The morphine spinal group had lower pain compared with the liposomal bupivacaine PAI group at 6 hours (0.9 ± 1.8 versus 1.8 ± 2.1, p = 0.035, mean difference: 1.0, 95% CI, 0.1–1.8), but there was no difference at 12 hours (0.8 ± 1.5 versus 1.5 ± 2.0, p = 0.086, mean difference: 0.7, 95% CI, ?0.1 to 1.5). The magnitude of the differences at 6 and 12 hours are near the lower end of minimal clinically important differences reported in the literature, and thus the improvement shown in this study may only represent a small clinical improvement. Both the liposomal bupivacaine group (13% [five of 40]) and the ropivacaine group (5% [two of 38]) had fewer incidents of itching (pruritus) than the spinal morphine group (38% [15 of 41]) (p = 0.001).

Conclusions

This prospective multicenter three-arm blind randomized controlled trial showed potentially improved pain control at 6 and 12 hours in the liposomal bupivacaine and intrathecal morphine groups compared with the ropivacaine group at the cost of much higher incidences of pruritus (itching) in the intrathecal morphine group. Based on these results, we prefer the use of PAI with liposomal bupivacaine as an alternative to spinal anesthesia with intrathecal morphine as a result of similar postoperative pain control and the potential for reducing adverse events.

Level of Evidence

Level I, therapeutic study.
  相似文献   
992.
One contested contraindication to medial unicompartmental knee arthroplasty (UKA) has been status of the patellofemoral joint. Surgeons have avoided UKA when the patellofemoral joint has radiographic evidence of arthritic changes. However, recent studies advocate ignoring patellofemoral joint status when considering UKA. The purpose of this study was to compare the failure rate of mobile-bearing, medial UKA in patients with and without preoperative radiographic evidence of patellofemoral joint degeneration. Preoperative radiographs from a random selection of 503 patients (638 knees) treated with UKA for anteromedial osteoarthritis were assessed by an observer blinded to clinical outcome. The patellofemoral joint was graded using the modified Altman classification from 0 to 3 with 0 being no evidence of changes and 3 being severe, and identified 396 grade 0, 168 grade 1, 65 grade 2, and 9 grade 3 knees. At 1- to 7-year follow-up, there have been 17 revisions for overall survivorship of 97.3%. Kaplan-Meier analysis predicted 97.9% survival in knees with patellofemoral joint disease and 93.8% survival in knees without patellofemoral joint disease at 70 months (P=.1). Failure requiring revision occurred in 3.5% (14/396) of grade 0 knees, 1.2% (2/168) of grade 1, 1.5% (1/65) of grade 2, and 0% (0/9) of grade 3. No survival difference was noted between knees with medial or lateral patellofemoral joint disease (P=.1). No knees were revised for progression of disease in the patellofemoral joint or anterior knee pain. In light of this investigation and the work of others, preoperative radiographic changes in the patellofemoral joint can be safely ignored when considering patients for medial UKA without compromising survivorship.  相似文献   
993.
Mice lacking granulocyte colony-stimulating factor (G-CSF) were generated by targeted disruption of the G-CSF gene in embryonal stem cells. G-CSF-deficient mice (genotype G-CSF-/-) are viable, fertile, and superficially healthy, but have a chronic neutropenia. Peripheral blood neutrophil levels were 20% to 30% of wild-type mice (genotype G- CSF+/+) and mice heterozygous for the null mutation had intermediate neutrophil levels, suggesting a gene-dosage effect. In the marrow of G- CSF-/- mice, granulopoietic precursor cells were reduced by 50% and there were reduced levels of granulocyte, macrophage, and blast progenitor cells. Despite G-CSF deficiency, mature neutrophils were still present in the blood and marrow, indicating that other factors can support neutrophil production in vivo. G-CSF-/- mice had reduced numbers of neutrophils available for rapid mobilization into the circulation by a single dose of G-CSF. G-CSF administration reversed the granulopoietic defect of G-CSF-/- mice. One day of G-CSF administration to G-CSF-/- mice elevated circulating neutrophil levels to normal, and after 4 days of G-CSF administration, G-CSF+/+ and G-CSF- /- marrows were morphologically indistinguishable. G-CSF-/- mice had a markedly impaired ability to control infection with Listeria monocytogenes, with diminished neutrophil and delayed monocyte increases in the blood and reduced infection-driven granulopoiesis. Collectively, these observations indicate that G-CSF is indispensible for maintaining the normal quantitative balance of neutrophil production during "steady-state" granulopoiesis in vivo and also implicate G-CSF in "emergency" granulopoiesis during infections.  相似文献   
994.

Background

Stage III and IV cancers of larynx and hypopharynx often require total laryngectomy which leaves the patient with severe communication handicap. In such laryngectomised patients tracheo-esophageal puncture is the best way for voice rehabilitation using either Blom-Singer® prosthesis or Provox® indwelling valve.

Methods

A prospective comparative study of Blom-Singer® prosthesis and Provox® indwelling valves placed in Tracheo-esophageal Punctures (TEP) for voice rehabilitation following total laryngectomy was carried out at the Tata Memorial Hospital, Mumbai and Malignant Diseases Treatment Centre of Armed Forces, to assess their efficacy. This report comprises of our experience in 41 (39 males and two females) laryngtectomees who underwent TEP of which 15 patients were fitted with low pressure Blom-Singer® prostheses and 26 with Provox® indwelling prostheses.

Results

Prostheses related problems like granuloma formation, leakage, candidal growth over the valves and prosthetic decay were significantly less in the patients fitted with Provox® prosthesis. Dislodgement of prosthesis with closure of the tract or persistent fistula formation and creation of false passage, while reinsertion were problems encountered in the Blom-Singer group. After three months, speech assessment revealed a better quality of voice production and patient compliance in maintaining the prosthesis in the case of Provox® indwelling valve.

Conclusion

In Indian scenario where illitracy amongst the patients hinders in maintainence of Blom-Singer® prosthesis, Provox® indwelling value is an appropriate choice for voice rehabilitation.Key Words: Tracheo-esophageal puncture (TEP), Blom-Singer® prosthesis, Provox® Valve  相似文献   
995.
We applied structural equation modeling to positron emission tomography data in humans to examine functional interactions between the right medial temporal lobe (MTL) and selected right neocortical regions in relation to visual recognition memory. Using a priori knowledge about anatomical connections between these regions as a guiding constraint, we modeled the pattern of interactions [i.e. covariances in regional cerebral blood flow (rCBF)] associated with episodic memory retrieval of spatial location and compared it with the pattern for retrieval of object identity. We also compared these patterns with those associated with perceptual matching of spatial location and object identity. Although displaying no difference in average rCBF across tasks, the right MTL showed domain-specific qualitative differences in interactions with posterior dorsal (parieto-occipital sulcus, supramarginal gyrus) and ventral regions (fusiform gyrus, superior temporal sulcus) but not with a prefrontal region. MTL interactions involving dorsal regions were positive in the spatial retrieval task but negative for object retrieval. Interactions involving ventral regions showed the reverse pattern. No comparable changes were observed during perceptual matching. Using control models, we demonstrated the neuroanatomical specificity of these results. Our results provide support for the notion that the nature of interactions between the MTL and posterior neocortex depends on the domain of information to-be- recovered.   相似文献   
996.

Objective

To screen the chitosan producing ability of endolichenic fungi and its antibacterial activity.

Methods

Lichen collected from mangroves was screened for endophytes and the chitosan producing ability of endolichenic fungi by submerged fermentation was also determined. Antibacterial activity was carried out against different pathogens.

Results

Totally 4 different groups of fungi were isolated from the lichen Roccella montagnei. Among the four genera, Aspergillus niger (A. niger) is potential to produce chitosan (1.3 g/L) on the twelfth day of incubation. Glucose plays an important role in the productivity of chitosan and the yield was maximum at 10% (1.93 g/L). Antibacterial activity revealed that Vibrio cholerae was sensitive to chitosan followed by Escherichia coli.

Conclusions

In conclusion, our findings suggest that A. niger is a potential candidate to produce more chitosan than the other strains and glucose plays an important role in the production of chitosan which proves to have a good antibacterial activity.  相似文献   
997.
998.
999.
OBJECTIVE: To pilot a provincial joint replacement registry using electronic point-of-care data collection. DESIGN: Data collection study. SETTING: Southwestern Ontario, which has a population base of 3.5 million people. PARTICIPANTS: Eighteen orthopedic surgeons. METHOD: Information on total hip and knee replacements was obtained by the orthopedic surgeons over a 6-month period. Information was obtained in paper form and electronically on hand-held computers. MAIN OUTCOME MEASURES: Patient demographics, waiting times from referral to operation, patient satisfaction and relevance and value of electronic records compared with paper records. MAIN RESULTS: Data were collected on 815 total hip and knee arthroplasties. A slightly greater number of hips required revision than knees. The majority of patients were in the 60 to 90-year age range. With respect to the waiting time from referral to operation 10% of patients waited less than 5 weeks, 50% waited less than 30 weeks, and 90% waited less than 59 weeks. There was a high level of patient satisfaction with the operation and with hospital care received. Most surgeons found that the gathering and use of data electronically was relevant and easy. The electronic data were more timely, accurate and complete than paper records. CONCLUSION: Electronic point-of-care data collection is appropriate, particularly in high-volume, high-cost surgical interventions such as total joint replacements.  相似文献   
1000.
Neonatal ovarian cysts: sonographic-pathologic correlation   总被引:4,自引:0,他引:4  
The authors reviewed the prenatal (11 infants) and postnatal (17 infants) sonograms and the clinical, surgical, and pathologic findings in 17 infants with an ovarian cyst to determine the sonographic features and natural history of neonatal ovarian cysts. An uncomplicated cyst (nontwisted, nonhemorrhagic) was completely anechoic and the cyst wall was imperceptible with sonography (five cases). A twisted or hemorrhagic cyst was cystic with a fluid-debris level, cystic with a retracting clot, septated with or without internal echoes, or solid (12 cases). These complicated cysts contained liquid and/or organized hematoma. Eleven of the 12 complicated cysts had a thin, highly echogenic wall. Cyst torsion commonly occurred in utero and could be diagnosed on prenatal sonograms by a typical sonographic appearance (eight cases). All of these infants were asymptomatic after birth. Four infants with hemorrhagic or twisted cysts were symptomatic. All cysts except one that resolved spontaneously were treated surgically, including three twisted cysts that showed no change in size over a 1-8-month interval. All of the cysts were of follicular origin.  相似文献   
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