Switch to
| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
1
|
| pubmed:dateCreated |
1992-3-3
|
| pubmed:abstractText |
The diagnostic accuracy of exercise electrocardiography has been improved by incorporation of R-wave gain factor to correct the measured ST-segment changes. If marked changes in R-wave amplitude occur in individual patients during cardiac operations, a similar gain factor correction may improve the intraoperative diagnosis of myocardial ischemia. This investigation was designed to determine the frequency and magnitude of intraoperative V5 R-wave amplitude changes during cardiac operations. Electrocardiograms were recorded from 83 patients while patients were awake, anesthetized (baseline), after placement of the Favaloro and Canadian sternal retractors, and at end-operation. Compared with baseline values, placement of the Canadian sternal retractor was associated with a reduction in V5 R-wave amplitude from 15 +/- 1 to 10 +/- 1 mm (mean +/- SEM), in V5 S-wave amplitude from 3.5 +/- 0.4 to 1.7 +/- 0.3 mm, and in absolute ST-segment deviation from 0.50 +/- 0.04 to 0.39 +/- 0.05 mm. Changes in V5 R-wave amplitude were correlated with changes in ST-segment deviation in patients with baseline ST-segment deviations greater than or equal to 0.5 mm (r = 0.55, P = 0.0004, n = 37). Changes associated with the Favaloro retractor and the respiratory cycle were less marked. However, the V5 R-wave amplitude was decreased from 15 +/- 1 to 9 +/- 1 mm at end-operation. In conclusion, sternal spreading with the Canadian retractor was associated with marked reductions in V5 R- and S-wave amplitudes and ST-segment deviations. Marked changes in V5 R-wave amplitude persisted after sternal closure.(ABSTRACT TRUNCATED AT 250 WORDS)
|
| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:citationSubset |
AIM
|
| pubmed:status |
MEDLINE
|
| pubmed:month |
Jan
|
| pubmed:issn |
0003-2999
|
| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:volume |
74
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
|
| pubmed:pagination |
26-31
|
| pubmed:dateRevised |
2006-11-15
|
| pubmed:meshHeading |
pubmed-meshheading:1734793-Blood Pressure,
pubmed-meshheading:1734793-Cardiac Surgical Procedures,
pubmed-meshheading:1734793-Electrocardiography,
pubmed-meshheading:1734793-Female,
pubmed-meshheading:1734793-Heart Rate,
pubmed-meshheading:1734793-Humans,
pubmed-meshheading:1734793-Intraoperative Period,
pubmed-meshheading:1734793-Male,
pubmed-meshheading:1734793-Monitoring, Intraoperative
|
| pubmed:year |
1992
|
| pubmed:articleTitle |
Electrocardiographic R-wave changes during cardiac surgery.
|
| pubmed:affiliation |
Department of Anesthesia, Harvard Medical School, Brigham and Women's Hospital, Boston, Massachusetts 02115.
|
| pubmed:publicationType |
Journal Article,
Research Support, Non-U.S. Gov't
|