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991.
Vitalis Mung'ayi Karen Mbaya Thikra Sharif Dorothy Kamya 《African health sciences》2015,15(2):466-479
Background
Spinal anaesthesia is a routinely used anaesthetic technique in elderly patients (> 60 years) undergoing operations involving the lower limbs, lower abdomen, pelvis and the perineum. Spinal anaesthesia has several advantages over general anaesthesia including stable haemodynamic variables, less blood loss, less post-operative pain, faster recovery time and less post-operative confusion. Despite these advantages, the sympathetic blockade induced by spinal anaesthesia can result in hypotension, bradycardia, dysrhythmias and cardiac arrests. Conventionally, spinal anaesthesia is performed at the level of L3,4 interspace; with a reported incidence of hypotension in the elderly ranging between 65% and 69%. A possible strategy for reducing spinal induced hypotension would be to minimize the peak block height to as low as possible for the planned procedure.Objective
To determine the difference in haemodynamic stability between elderly patients undergoing spinal anaesthesia at L5, S1 interspace compared to those at L3, 4.Methods
Thirty two elderly patients scheduled for lower limb or pelvic surgery under spinal anaesthesia were randomized into 2 groups (control group and intervention group) using a computer generated table of numbers.Control group; received 2.5 mls 0.5% hyperbaric bupivacaine injected intrathecally at the L3, 4 interspace and Intervention group; 2.5mls 0.5% hyperbaric bupivacaine injected intrathecally at the L5, S1 interspaceResults
The two groups had similar baseline characteristics in age, sex, body mass index and use of anti-hypertensive medications. There was 68.8% proportion of hypotension in the control group and 75% in the intervention group. The difference was not found to be statistically significant (p= 0.694). During the study period, there were 106 episodes of hypotension, out of which, 65 were in the control group and 41 in the intervention group (p=0.004).. Linear regression analysis of the decrease in mean arterial pressures (MAP) showed a higher decrease in MAP in the control group (p 0.018). There were more crystalloids used in the control group (1006mls ± 374) than in the intervention group (606mls ±211) with a p< 0.0001. There was no difference in the amounts of vasopressors used between the two groups (p=0.288). There was no difference in the change in heart rates, conversion to general anaesthesia, use of supplementary intravenous fentanyl and the peak maximum block level achieved. The time to peak maximum sensory block level was 9.06min and 13.07min in the control group and intervention groups, respectively (p<0.0001).Conclusion
Among this population, there was no difference in the proportion of those with hypotension between the elderly patients who received their spinal anaesthesia at L3,4 and those who received spinal anaesthesia at L5,S1. The intervention group had better outcomes with significantly less episodes of hypotension. It took a longer time to achieve a maximum peak sensory block in the intervention group. Performing spinal anaesthesia at the level of L5,S1 was found to provide an adequate sensory block for a wide range of pelvic, perineal and lower limb surgeries. 相似文献992.
Marie-Luise Berres Karen Phaik Har Lim Tricia Peters Jeremy Price Hitoshi Takizawa Hélène Salmon Juliana Idoyaga Albert Ruzo Philip J. Lupo M. John Hicks Albert Shih Stephen J. Simko Harshal Abhyankar Rikhia Chakraborty Marylene Leboeuf Monique Beltr?o Sérgio A. Lira Kenneth M. Heym Bj?rn E. Clausen Venetia Bigley Matthew Collin Markus G. Manz Kenneth McClain Miriam Merad Carl E. Allen 《The Journal of experimental medicine》2015,212(2):281
993.
994.
Rohit B. Sharma Amy C. O’Donnell Rachel E. Stamateris Binh Ha Karen M. McCloskey Paul R. Reynolds Peter Arvan Laura C. Alonso 《The Journal of clinical investigation》2015,125(10):3831-3846
Although stem cell populations mediate regeneration of rapid turnover tissues, such as skin, blood, and gut, a stem cell reservoir has not been identified for some slower turnover tissues, such as the pancreatic islet. Despite lacking identifiable stem cells, murine pancreatic β cell number expands in response to an increase in insulin demand. Lineage tracing shows that new β cells are generated from proliferation of mature, differentiated β cells; however, the mechanism by which these mature cells sense systemic insulin demand and initiate a proliferative response remains unknown. Here, we identified the β cell unfolded protein response (UPR), which senses insulin production, as a regulator of β cell proliferation. Using genetic and physiologic models, we determined that among the population of β cells, those with an active UPR are more likely to proliferate. Moreover, subthreshold endoplasmic reticulum stress (ER stress) drove insulin demand–induced β cell proliferation, through activation of ATF6. We also confirmed that the UPR regulates proliferation of human β cells, suggesting that therapeutic UPR modulation has potential to expand β cell mass in people at risk for diabetes. Together, this work defines a stem cell–independent model of tissue homeostasis, in which differentiated secretory cells use the UPR sensor to adapt organ size to meet demand. 相似文献
995.
996.
997.
Jane Topolovec-Vranic Marlene Santos Andrew J Baker Orla M Smith Karen EA Burns 《Canadian respiratory journal》2014,21(5):293-296
INTRODUCTION:
Alterations from first-party and surrogate decision-maker consent can enhance the feasibility of research involving critically ill patients.OBJECTIVE:
To describe the use of a deferred-consent model to enable participation of critically ill patients in a minimal-risk biomarker study.METHODS:
A prospective observational study was conducted in which serum biomarker samples were collected three times daily over the first 14 days following aneurysmal subarachnoid hemorrhage. Sample collection was initiated on intensive care unit admission and consent was obtained when research personnel could approach the patient or the patient’s surrogate decision maker.RESULTS:
Twenty-seven patients were eligible for the study, of whom only five were capable of providing informed consent. Full consent was obtained for 21 (78%) patients through self- (n=4) and surrogate (n=17) consent. Partial consent or refusal (only permitting the collection of blood samples as a part of routine care or use of data) occurred in three patients. Among the 22 consents sought from surrogates, three (11%) refused participation. The refusals included the sickest patients in the cohort. Once consent was provided, no patient or surrogate withdrew consent before study completion.DISCUSSION:
Use of a deferred consent model enabled participation of critically ill patients in a minimal-risk biomarker study with no withdrawals.CONCLUSIONS:
Further research and enhanced awareness of the potential utility of hybrid models, including deferred consent in addition to patient or surrogate consent, in the conduct of low-risk and minimally interventional time-sensitive studies of critically ill patients are required. 相似文献998.
Rony Zachariah Nathalie Guillerm Selma Berger Ajay M. V. Kumar Srinath Satyanarayana Karen Bissell Mary Edginton Sven Gudmund Hinderaker Katie Tayler‐Smith Rafael Van den Bergh Mohammed Khogali Marcel Manzi Anthony J. Reid Andrew Ramsay John C. Reeder Anthony D. Harries 《Tropical medicine & international health : TM & IH》2014,19(9):1068-1075
999.
Daniel R Perez Nancy E Kemeny Karen T Brown Alexandra N Gewirtz Philip B Paty William R Jarnagin Michael I D'Angelica 《HPB : the official journal of the International Hepato Pancreato Biliary Association》2014,16(8):744-748
Background
Hepatic arterial infusion (HAI) chemotherapy is an effective treatment for patients with liver malignancy. Extrahepatic perfusion (EHP) after HAI pump placement requires correction prior to starting chemotherapy. The aim of this study was to define the origin of arterial branches causing EHP in order to determine if alterations in surgical technique during pump placement might prevent EHP.Methods
A prospectively maintained, single-centre HAI database was reviewed for all patients (2008–2011) with EHP. The origin of arterial branches causing EHP was classified anatomically and patient outcomes were analysed.Results
Of the 327 patients with pumps implanted, 24 evidenced EHP. The arterial branch responsible for EHP perfused the duodenum, pancreas and/or stomach. The branch responsible for EHP arose from the proper hepatic artery (PHA), 1st, 2nd, or 3rd order hepatic artery branches in 7, 10, 5 and 2 patients, respectively. The majority of branches beyond the PHA causing EHP (13/17) originated from the right hepatic artery. In 18 patients, aberrant branches were successfully treated with embolization.Conclusion
These findings provide the anatomic basis for prevention of up to one-third of the cases of EHP intra-operatively, decreasing the number of patients who will require additional procedures for correction of EHP post-operatively. 相似文献1000.
Karen Sliwa Denise Hilfiker‐Kleiner Alexandre Mebazaa Mark C. Petrie Aldo P. Maggioni Vera Regitz‐Zagrosek Maria Schaufelberger Luigi Tavazzi Dirk J. van Veldhuisen Jolien W. Roos‐Hesslink Ajay J. Shah Petar M. Seferovic Uri Elkayam Karin van Spaendonck‐Zwarts Katrin Bachelier‐Walenta Frederic Mouquet Elisabeth Kraigher‐Krainer Roger Hall Piotr Ponikowski John J. V. McMurray Burkert Pieske 《European journal of heart failure》2014,16(5):583-591