INTRODUCTION: The implementation of open posterior component separation (PCS) surgery has led to improved outcomes for complex hernias. While the PCS technique has been shown to decrease recurrence rates, and provide a feasible option to repair hernias in nontraditional locations, there is still significant postoperative pain associated with the laparotomy and extensive abdominal wall manipulation. Systemic opioids and thoracic epidural analgesia (TEA) are both commonly utilized, either together or independently, as postoperative analgesic regimens. The benefits of TEA have been studied following a variety of surgeries, however to date no study has been performed to investigate its efficacy in this particular surgery. The aim of this study is to evaluate the benefits of TEA following open PCS. We hypothesized that the incorporation of TEA in a patients postoperative analgesic regimen would show an advantage in time to bowel recovery. METHODS: An electronic medical record query was done to identify patients who had undergone an open PCS. Once this list was compiled, a retrospective chart review was performed and patients receiving TEA (either alone or combined with systemic opioids) were compared to patients receiving only systemic opioids. The primary endpoint compared time to resumption of a full diet, given by the patients postoperative day (POD). Secondarily, time to resumption of a liquid diet, postoperative length of stay (LOS), intensive care unit (ICU) admission rate, ICU LOS, and rates of several postoperative complications were all recorded and compared. A post-hoc analysis was also performed using the same endpoints. This analysis compared cohorts of patients receiving TEA and avoiding all systemic opioids, to patients who received systemic opioids (whether alone or combined with TEA). RESULTS: Based on inclusion parameters, 101 patients met criteria for analysis. In the initial analysis, 62 patients received TEA with or without systemic opioids, and 39 patients received only systemic opioids. In comparing these groups, there was no statistically significant difference in time to full diet (TEA 2.6 ± 1.7 vs Systemic opioids 3.1 ± 2.1 [mean POD ± SD]; P=0.21). In addition, no differences were found in the secondary outcomes of time to liquid diet, ICU admission, ICU LOS, or postoperative complications. In the post-hoc analysis, the 37 patients that received only TEA, were compared against 64 patients that received systemic opioids (either with or without TEA). In this comparison, the group receiving only TEA was found to have a statically shorter time to bowel recovery compared to patients receiving systemic opioids (TEA alone 2.2 ± 1.0 vs Systemic opioids 3.2 ± 2.2, P=0.0033). This subgroup (TEA only) also showed statically shorter time to liquid diet and a decreased postoperative LOS. CONCLUSION: For patients undergoing an open PCS, the inclusion of TEA in the postoperative analgesic regimen did not shorten return of bowel function. However, when TEA was utilized and systemic opioids were avoided, time to bowel recovery and hospital LOS were both significantly shortened.

Made available in DSpace on 2014-06-11T19:22:21Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-02-27Bitstream added on 2014-06-13T19:27:34Z : No. of bitstreams: 1 oliveira_gcv_me_botfm.pdf: 521554 bytes, checksum: 4e1594735e9b4ade8985592087d02570 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Foi realizado estudo experimental em cães para avaliar a eficácia da anestesia peridural torácica e seus efeitos na respiração, comparando-se dois volumes, 0,25 e 0,33 ml/kg do anestésico local ropivacaína a 0,75%. Para isso foram utilizados oito animais, sem raça definida, com idade entre um e três anos, com peso médio de 24,7 ± 6,3 Kg, em boas condições de saúde. Para isso foi necessária anestesia prévia dos animais a fim de se determinar a concentração anestésica mínima na qual o animal apresentasse resposta positiva a um estímulo elétrico. Sendo assim a indução foi realizada com isofluorano na concentração inicial de 5% no vaporizador calibrado, através de máscara facial e a intubação foi efetuada. O estímulo elétrico foi realizado com corrente de 50 V em 50 ciclos/s de 10 milisegundos. Se a resposta fosse negativa, a concentração era reduzida em 0,2%, sendo o procedimento repetido até que o animal apresentasse resposta positiva para a determinação do estímulo supra máximo positivo. Um cateter peridural foi introduzido do espaço lombossacro até a região torácica das vértebras T1-T2. Foi administrada ropivacaína e as avaliações foram realizadas por dois avaliadores que não tinham conhecimento do tratamento utilizado. Os parâmetros aferidos foram freqüência cardíaca, respiratória, pressões arteriais, ritmo cardíaco, concentração expirada de CO2, volume minuto, volume corrente, hemogasometria e temperatura esofágica. A avaliação do bloqueio sensitivo foi realizada através da avaliação do estímulo elétrico e de pinçamento da pele para avaliação do panículo nervoso. Houve redução da freqüência cardíaca e de pressão arterial, o que revela um bloqueio simpático com os dois grupos. Houve depressão respiratória, pois os dois grupos apresentaram elevação do CO2, e foram colocados sob ventilação controlada... / Experimental study was conducted in dogs to assess the effectiveness of the thoracic epidural anesthesia and their effects on respiration, compared two volumes, 0.25 and 0.33 ml / kg of local anesthetic ropivacaine at 0.75%. For that eight animals were used, mixed breed, aged between one and three years, with average weight of 24.7 ± 6.3 kg, in good health. For this was required anesthesia of the animals prior to find the minimum anesthesia concentration that the animal had a positive response to electrical stimulation. Thus the induction was performed with isoflurane in the initial concentration of 5% in precision vaporizer by face mask and intubation was performed. The electrical stimulation was performed with current of 50 V at 50 cycles / s, 10 milliseconds. If the purposeful gross movement was negative, the concentration was reduced by 0.2%, and the procedure repeated until the animal had a positive response for determining the maximum positive stimulus above. An epidural catheter was introduced into the space lombossacro to the region of thoracic vertebrae T1-T2. Ropivacaine was administered and the evaluations were conducted by two evaluators who were not aware of treatment used. The parameters were measured heart rate, breathing, blood pressure, heart rate, expired concentration of CO2, minute volume, tidal volume, blood gas and esophageal temperature. The assessment of sensory block was done through evaluation of electrical stimulation and clamping the skin to assess the panículous nervous. Decreased heart rate and blood pressure, which shows a sympathetic block with the two groups. There was respiratory depression, since both groups had elevation of CO2, and were placed under controlled ventilation, which prevented the evaluation of spontaneous ventilation. The pinch of the skin test showed a blockage in extensive loss of nerve panículous in two groups, with no statistical... (Complete abstract click electronic access below)

Orientador: Valéria Nobre Leal de Souza Oliva / Banca: Denise Tabachi Fantoni / Banca: Stélio Pacca Loureiro Luna / Resumo: Foi realizado estudo experimental em cães para avaliar a eficácia da anestesia peridural torácica e seus efeitos na respiração, comparando-se dois volumes, 0,25 e 0,33 ml/kg do anestésico local ropivacaína a 0,75%. Para isso foram utilizados oito animais, sem raça definida, com idade entre um e três anos, com peso médio de 24,7 ± 6,3 Kg, em boas condições de saúde. Para isso foi necessária anestesia prévia dos animais a fim de se determinar a concentração anestésica mínima na qual o animal apresentasse resposta positiva a um estímulo elétrico. Sendo assim a indução foi realizada com isofluorano na concentração inicial de 5% no vaporizador calibrado, através de máscara facial e a intubação foi efetuada. O estímulo elétrico foi realizado com corrente de 50 V em 50 ciclos/s de 10 milisegundos. Se a resposta fosse negativa, a concentração era reduzida em 0,2%, sendo o procedimento repetido até que o animal apresentasse resposta positiva para a determinação do estímulo supra máximo positivo. Um cateter peridural foi introduzido do espaço lombossacro até a região torácica das vértebras T1-T2. Foi administrada ropivacaína e as avaliações foram realizadas por dois avaliadores que não tinham conhecimento do tratamento utilizado. Os parâmetros aferidos foram freqüência cardíaca, respiratória, pressões arteriais, ritmo cardíaco, concentração expirada de CO2, volume minuto, volume corrente, hemogasometria e temperatura esofágica. A avaliação do bloqueio sensitivo foi realizada através da avaliação do estímulo elétrico e de pinçamento da pele para avaliação do panículo nervoso. Houve redução da freqüência cardíaca e de pressão arterial, o que revela um bloqueio simpático com os dois grupos. Houve depressão respiratória, pois os dois grupos apresentaram elevação do CO2, e foram colocados sob ventilação controlada... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Experimental study was conducted in dogs to assess the effectiveness of the thoracic epidural anesthesia and their effects on respiration, compared two volumes, 0.25 and 0.33 ml / kg of local anesthetic ropivacaine at 0.75%. For that eight animals were used, mixed breed, aged between one and three years, with average weight of 24.7 ± 6.3 kg, in good health. For this was required anesthesia of the animals prior to find the minimum anesthesia concentration that the animal had a positive response to electrical stimulation. Thus the induction was performed with isoflurane in the initial concentration of 5% in precision vaporizer by face mask and intubation was performed. The electrical stimulation was performed with current of 50 V at 50 cycles / s, 10 milliseconds. If the purposeful gross movement was negative, the concentration was reduced by 0.2%, and the procedure repeated until the animal had a positive response for determining the maximum positive stimulus above. An epidural catheter was introduced into the space lombossacro to the region of thoracic vertebrae T1-T2. Ropivacaine was administered and the evaluations were conducted by two evaluators who were not aware of treatment used. The parameters were measured heart rate, breathing, blood pressure, heart rate, expired concentration of CO2, minute volume, tidal volume, blood gas and esophageal temperature. The assessment of sensory block was done through evaluation of electrical stimulation and clamping the skin to assess the panículous nervous. Decreased heart rate and blood pressure, which shows a sympathetic block with the two groups. There was respiratory depression, since both groups had elevation of CO2, and were placed under controlled ventilation, which prevented the evaluation of spontaneous ventilation. The pinch of the skin test showed a blockage in extensive loss of nerve panículous in two groups, with no statistical... (Complete abstract click electronic access below) / Mestre

<p>The aim was to study pathophysiological mechanisms and risk factors for developing atrial fibrillation (AF) after coronary artery bypass grafting (CABG), and the effect of thoracic epidural anaesthesia (TEA).</p><p>The study comprised 141 patients undergoing CABG, including 45 patients randomised for TEA intra- and postoperatively. All patients underwent 24-hour Holter monitoring pre- and postoperatively for the analysis of arrhythmias and heart rate variability (HRV). Catecholamines and neuropeptides (reflecting sympathetic and parasympathetic activity), atrial peptides and echocardiographically assessed atrial arias were obtained pre- and postoperatively.</p><p>Logistic regression analysis identified body mass index (BMI), maximum supraventricular beats (SPB) per minute, and total amount of cardioplegia as independent predictors of postoperative AF. Patients developing AF showed limited diurnal variation of HRV preoperatively. All HRV parameters decreased significantly in all patients postoperatively. The significant postoperative increase in atrial areas and atrial peptides did not differ between patients developing AF and those who did not. TEA had no effect on the incidence of postoperative AF, but resulted in lower heart rate, less increase in adrenaline levels, and decreased neuropeptide levels (reflecting sympathetic and parasympathetic activity). AF was initiated by an SPB in 72.4% of non-TEA and 100% of TEA treated patients, whereas changes in heart rate only, before onset, were seen in 17.2% non-TEA patients.</p><p>The observed risk factors, SPB and cardioplegia, may both induce electrophysiological changes known to increase the susceptibility to AF. The observed postoperative atrial dilatation and autonomic imbalance, indicated by HRV and neuropeptide levels, may further favour the development of AF. The observation that a majority of postoperative AF was initiated by a premature atrial contraction supports our hypothesis that latent atrial foci may be a major trigger mechanism of postoperative AF.</p>

The aim was to study pathophysiological mechanisms and risk factors for developing atrial fibrillation (AF) after coronary artery bypass grafting (CABG), and the effect of thoracic epidural anaesthesia (TEA). The study comprised 141 patients undergoing CABG, including 45 patients randomised for TEA intra- and postoperatively. All patients underwent 24-hour Holter monitoring pre- and postoperatively for the analysis of arrhythmias and heart rate variability (HRV). Catecholamines and neuropeptides (reflecting sympathetic and parasympathetic activity), atrial peptides and echocardiographically assessed atrial arias were obtained pre- and postoperatively. Logistic regression analysis identified body mass index (BMI), maximum supraventricular beats (SPB) per minute, and total amount of cardioplegia as independent predictors of postoperative AF. Patients developing AF showed limited diurnal variation of HRV preoperatively. All HRV parameters decreased significantly in all patients postoperatively. The significant postoperative increase in atrial areas and atrial peptides did not differ between patients developing AF and those who did not. TEA had no effect on the incidence of postoperative AF, but resulted in lower heart rate, less increase in adrenaline levels, and decreased neuropeptide levels (reflecting sympathetic and parasympathetic activity). AF was initiated by an SPB in 72.4% of non-TEA and 100% of TEA treated patients, whereas changes in heart rate only, before onset, were seen in 17.2% non-TEA patients. The observed risk factors, SPB and cardioplegia, may both induce electrophysiological changes known to increase the susceptibility to AF. The observed postoperative atrial dilatation and autonomic imbalance, indicated by HRV and neuropeptide levels, may further favour the development of AF. The observation that a majority of postoperative AF was initiated by a premature atrial contraction supports our hypothesis that latent atrial foci may be a major trigger mechanism of postoperative AF.

OBJECTIVES: Standard blood flow rates for cardiopulmonary bypass have been assumed to be the same for awake cardiac surgery with thoracic epidural anesthesia as for general anesthesia. However, compared to general anesthesia, awake cardiac surgery with epidural anesthesia may be associated with higher oxygen consumption due to missing effect of general anesthetics. This may result in insufficient oxygen delivery and lactic acidosis when standard blood flow rates were used. The primary aim of our study was to investigate if standard blood flow rates are adequate in awake cardiac surgery. The secondary aim was to evaluate postoperative clinical outcomes of patients undergoing awake cardiac surgery. METHODS: Forty-seven patients undergoing elective on-pump cardiac surgery were assigned to receive either epidural (Group TEA, n=17), combined (Group TEA-GA, n=15) or general (Group GA, n=15) anesthesia. To monitor adequacy of standard blood flow rates, arterial lactate, acid base parameters, central venous and jugular bulb saturation were measured at six time points during in all groups. Blood flow rates were adjusted when needed. Subsequently, early and late postoperative outcome data including hospital and 3-year mortality was recorded and compared among the study groups RESULTS: No lactic acidosis has...

A total of 49 patients were studied, using invasive hemodynamic techniques with systemic arterial, pulmonary artery and right atrial pressure recordings together with thermodilution cardiac output determinations. Sixteen of the patients were also subjected to cardiometabolic studies, using measurement of coronary sinus blood flow by the continuous thermodilution technique and analyses of oxygen content and lactate concentration in the systemic and coronary circulation. A common denominator in the five investigations was, that a distributive cardiovascular dysequilibrium was either induced (for surgical or anaesthesiological reasons) or already present due to a pathological condition. Thoracic epidural block from T 1 to T 12 induced marked decrease in systemic blood pressure due to vasodilation and impairment of cardiac performance. Prenalterol administration effectively abolished the low blood pressure by its marked inotropic action, having no effect on systemic vascular resistance. Myocardial oxygen consumption changed in parallel with the changes in cardiac work following both thoracic epidural block and prenalterol. Coronary vascular resistance was markedly decreased by the block and was not affected by prenalterol. It is suggested, that the critically low perfusion pressure is the main cause of the coronary vasodilation and that alpha-blockade induced by the thoracic epidural block is of less importance. The combination of a thoracic epidural block from T 1 to T 12 and selective ßi-stimulation with prenalterol was an effective way to modify the cardiovascular response to infrarenal aortic cross clamping. This treatment transferred the patients to a more favourable cardiac function curve and possibly facilitated the redistribution of blood flow in association with clamping. In association with declamping of the infrarenal aorta or the common iliac arteries, volume loading to a slightly elevated left ventricular filling pressure shortly before declamping was an effective way to counteract the expected blood pressure drop. A normal left ventricular filling pressure prior to declamping did not prevent the blood pressure drop following declamping. It is suggested, that mismatching between vascular volume and blood volume is the main cause of declamping hypotension. In patients with low resistance, distributive septic shock caused by gram negative bacteremias and signs of impaired cardiac function, prenalterol effectively reversed the hypotension and improved tissue perfusion by selectively increasing cardiac output. In parallel to the increased cardiac work, an increase in myocardial metabolic demand was demonstrated. / digitalisering@umu.se

OBJECTIVES: Standard blood flow rates for cardiopulmonary bypass have been assumed to be the same for awake cardiac surgery with thoracic epidural anesthesia as for general anesthesia. However, compared to general anesthesia, awake cardiac surgery with epidural anesthesia may be associated with higher oxygen consumption due to missing effect of general anesthetics. This may result in insufficient oxygen delivery and lactic acidosis when standard blood flow rates were used. The primary aim of our study was to investigate if standard blood flow rates are adequate in awake cardiac surgery. The secondary aim was to evaluate postoperative clinical outcomes of patients undergoing awake cardiac surgery. METHODS: Forty-seven patients undergoing elective on-pump cardiac surgery were assigned to receive either epidural (Group TEA, n=17), combined (Group TEA-GA, n=15) or general (Group GA, n=15) anesthesia. To monitor adequacy of standard blood flow rates, arterial lactate, acid base parameters, central venous and jugular bulb saturation were measured at six time points during in all groups. Blood flow rates were adjusted when needed. Subsequently, early and late postoperative outcome data including hospital and 3-year mortality was recorded and compared among the study groups RESULTS: No lactic acidosis has...