Abstract:
:Although previous studies have established the feasibility of monitoring esophageal temperature during radiofrequency cardiac ablation using an esophageal temperature probe (ETP), some questions remain regarding its efficacy. The aims of this study were to study the effect of the location of the ETP on the temperature reached, and to test the characteristics of ETP as used in clinical practice. We constructed an agar phantom to model the thermal and electrical characteristics of the biological tissues (left atrium, esophagus and connective tissue). The ETP was positioned at 6.5 mm from an ablation electrode and at distances of 0, 5, 10, 15, 20 mm from the catheter axis. A thermocouple was located on the probe to measure the actual temperature of the external esophageal layer during the ablations (55 degrees C, 60 s). The mean temperatures reached at the thermocouple were significantly higher than those measured by the ETP (48.3 +/- 1.9 degrees C versus 39.6 +/- 1.1 degrees C). The temperature values measured with the ETP were significantly lower when the probe was located further from the catheter axis (up to 2.5 degrees C lower when the distance from the probe-catheter axis was 2 cm). The dynamic calibration of the ETP showed a mean value for the time constant of 8 s. In conclusion, the temperature measured by the ETP always underestimates the temperature reached in the thermocouple. This fact can be explained by the distance gap between the thermocouple and probe and by the dynamic response of the ETP. The longer the distance between the ETP and catheter axis, the higher is the temperature difference.
journal_name
Physiol Measjournal_title
Physiological measurementauthors
Rodríguez I,Lequerica JL,Berjano EJ,Herrero M,Hornero Fdoi
10.1088/0967-3334/28/5/001subject
Has Abstractpub_date
2007-05-01 00:00:00pages
453-63issue
5eissn
0967-3334issn
1361-6579pii
S0967-3334(07)36017-6journal_volume
28pub_type
杂志文章abstract::Neural gastric electrical stimulation (NGES) is a new method for invoking gastric contractions under microprocessor control. However, optimization of this technique using feedback mechanisms to minimize power consumption and maximize effectiveness has been lacking. The present pilot study proposes a prototype feedback...
journal_title:Physiological measurement
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abstract::The changes in haemoglobin oxygenation (SO2) occurring in the tuberculin reaction in human skin were measured using macro- and micro-lightguide spectrophotometry and the results compared. A significant difference was found between the measurements from the respective instruments, demonstrating that the micro-lightguid...
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更新日期:1994-05-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章,评审
doi:10.1088/1361-6579/ab3827
更新日期:2019-09-03 00:00:00
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更新日期:2014-08-01 00:00:00
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doi:10.1088/0967-3334/37/7/981
更新日期:2016-07-01 00:00:00
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pub_type: 杂志文章
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/36/10/2159
更新日期:2015-10-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/38/1/63
更新日期:2017-01-01 00:00:00
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pub_type: 杂志文章
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更新日期:2019-07-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
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更新日期:2017-06-22 00:00:00
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doi:10.1088/1361-6579/aa9d60
更新日期:2018-01-31 00:00:00
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pub_type: 杂志文章
doi:10.1088/0967-3334/31/8/S06
更新日期:2010-08-01 00:00:00
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journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
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更新日期:1996-08-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/16/4/003
更新日期:1995-11-01 00:00:00
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pub_type: 杂志文章
doi:10.1088/0967-3334/28/7/S10
更新日期:2007-07-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/ab921e
更新日期:2020-07-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
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更新日期:2017-07-24 00:00:00
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pub_type: 杂志文章
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更新日期:2004-12-01 00:00:00
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更新日期:2010-07-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
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更新日期:2015-06-01 00:00:00
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更新日期:2020-07-09 00:00:00
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更新日期:2005-12-01 00:00:00
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更新日期:2009-07-01 00:00:00
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更新日期:2020-05-07 00:00:00
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更新日期:2017-02-01 00:00:00