Orthotopic liver transplantation can be marked by significant hemodynamic instability requiring the use of a variety of hemodynamic monitors to aide in intraoperative management. Invasive blood pressure monitoring is ...Orthotopic liver transplantation can be marked by significant hemodynamic instability requiring the use of a variety of hemodynamic monitors to aide in intraoperative management. Invasive blood pressure monitoring is essential,but the accuracy of peripheral readings in comparison to central measurements has been questioned. When discrepancies exist,central mean arterial pressure,usually measured at the femoral artery,is considered more indicative of adequateperfusion than those measured peripherally. The traditional pulmonary artery catheter is less frequently used due to its invasive nature and known limitations in measuring preload but still plays an important role in measuring cardiac output(CO) when required and in the management of portopulmonary hypertension. Pulse wave analysis is a newer technology that uses computer algorithms to calculate CO,stroke volume variation(SVV) and pulse pressure variation(PPV). Although SVV and PPV have been found to be accurate predicators of fluid responsiveness,CO measurements are not reliable during liver transplantation. Transesophageal echocardiography is finding an increasing role in the realtime monitoring of preload status,cardiac contractility and the diagnosis of a variety of pathologies. It is limited by the expertise required,limited transgastric views during key portions of the operation,the potential for esophageal varix rupture and difficulty in obtaining quantitative measures of CO in the absence of tricuspid regurgitation.展开更多
Background The value of somatosensory evoked potentials （SEPs） in the diagnosis and prognosis of cervical spondylotic myelopathy, as well as the usefulness of monitoring intraoperative potentials in terms of safety ...Background The value of somatosensory evoked potentials （SEPs） in the diagnosis and prognosis of cervical spondylotic myelopathy, as well as the usefulness of monitoring intraoperative potentials in terms of safety and predictive factors were investigated. Methods Each of the 76 myelopathic patients underwent surgical intervention. According to the wave configurations of the SEPs, the cases were categorised into four groups： Type Ⅰ, Ⅱ, Ⅲ and Ⅳ. The clinical myelopathy disability was classified and the severity of neurological deficits was scored. Clinical function after surgery was evaluated. Preoperative potentials and intraoperative monitoring were categorized. The correlations between .evoked potentials detection, monitoring, myelopathy disability and surgical outcome in the different groups were discussed. Results According to the configurations of the SEPs, there were 27 patients （36%） of Type Ⅰ, 30 patients （39%） of Type Ⅱ, 8 patients （11%） of Type Ⅲ, and 11 patients （14%） of Type Ⅳ. The categorised evoked potentials were shown to be significantly associated with the clinical representation of myelopathy （P 〈0.01） and the recovery rate from identifiable SEPs waves （groups A, B and C） was significantly higher than unidentifiable waves （group D, P〈0.01）. A deterioration of SEPs was detected in 23 cases （30%）, whereas there was no change in 40 cases （53%） and improvements in 13 cases （17%）. A significant difference in recovery rates could be observed in various monitoring groups within the short-term follow-up period, while there were no obvious differences in the long-term follow-up groups. Conclusions SEP technique is a valuable and practical tool for the diagnosis, monitoring and prognosis of myelopathy. Classified evoked potentials are well correlated with cervical spondylotic myelopathy disability, and unidentifiable SEPs waves in patients are indicative of a relatively poor outcome. In addition, intraoperative monitoring of SEPs plays an i展开更多
文摘Orthotopic liver transplantation can be marked by significant hemodynamic instability requiring the use of a variety of hemodynamic monitors to aide in intraoperative management. Invasive blood pressure monitoring is essential,but the accuracy of peripheral readings in comparison to central measurements has been questioned. When discrepancies exist,central mean arterial pressure,usually measured at the femoral artery,is considered more indicative of adequateperfusion than those measured peripherally. The traditional pulmonary artery catheter is less frequently used due to its invasive nature and known limitations in measuring preload but still plays an important role in measuring cardiac output(CO) when required and in the management of portopulmonary hypertension. Pulse wave analysis is a newer technology that uses computer algorithms to calculate CO,stroke volume variation(SVV) and pulse pressure variation(PPV). Although SVV and PPV have been found to be accurate predicators of fluid responsiveness,CO measurements are not reliable during liver transplantation. Transesophageal echocardiography is finding an increasing role in the realtime monitoring of preload status,cardiac contractility and the diagnosis of a variety of pathologies. It is limited by the expertise required,limited transgastric views during key portions of the operation,the potential for esophageal varix rupture and difficulty in obtaining quantitative measures of CO in the absence of tricuspid regurgitation.
文摘Background The value of somatosensory evoked potentials （SEPs） in the diagnosis and prognosis of cervical spondylotic myelopathy, as well as the usefulness of monitoring intraoperative potentials in terms of safety and predictive factors were investigated. Methods Each of the 76 myelopathic patients underwent surgical intervention. According to the wave configurations of the SEPs, the cases were categorised into four groups： Type Ⅰ, Ⅱ, Ⅲ and Ⅳ. The clinical myelopathy disability was classified and the severity of neurological deficits was scored. Clinical function after surgery was evaluated. Preoperative potentials and intraoperative monitoring were categorized. The correlations between .evoked potentials detection, monitoring, myelopathy disability and surgical outcome in the different groups were discussed. Results According to the configurations of the SEPs, there were 27 patients （36%） of Type Ⅰ, 30 patients （39%） of Type Ⅱ, 8 patients （11%） of Type Ⅲ, and 11 patients （14%） of Type Ⅳ. The categorised evoked potentials were shown to be significantly associated with the clinical representation of myelopathy （P 〈0.01） and the recovery rate from identifiable SEPs waves （groups A, B and C） was significantly higher than unidentifiable waves （group D, P〈0.01）. A deterioration of SEPs was detected in 23 cases （30%）, whereas there was no change in 40 cases （53%） and improvements in 13 cases （17%）. A significant difference in recovery rates could be observed in various monitoring groups within the short-term follow-up period, while there were no obvious differences in the long-term follow-up groups. Conclusions SEP technique is a valuable and practical tool for the diagnosis, monitoring and prognosis of myelopathy. Classified evoked potentials are well correlated with cervical spondylotic myelopathy disability, and unidentifiable SEPs waves in patients are indicative of a relatively poor outcome. In addition, intraoperative monitoring of SEPs plays an i
