Response to Letter Regarding Article, “Iatrogenic Giant Osborn Waves”
We appreciate Drs Joynt and Edelman's thoughtful comments on our recent publication.1 They suggested that the presence of Osborn waves on ECGs of patients undergoing therapeutic hypothermia depends not only on core body temperature, but also on abnormalities of blood pH. After resuscitation, our patient was initially acidotic, and this was driven mainly by increased lactic acid levels. However, once therapeutic hypothermia was introduced, pH had already normalized (7.37) and remained within normal limits (7.35) even when profound hypothermia (80.6°F) was noted. In a study published in 1959 by Emslie-Smith et al,2 no correlation was found between blood pH and the development of Osborn J waves in hypothermic dogs. Moreover, the deflection was also recorded in dogs that became alkalotic after hyperventilation. More recently, Brunson et al3 found that J waves appeared on the ECG of hypothermic dogs even when pH was within the physiological range. Although low blood pH levels are a common finding in post-resuscitated patients undergoing therapeutic hypothermia, it remains unclear whether they affect the appearance of Osborn waves.
Antonios N. Pavlidis, MD, PhD
Antreas Giannakopoulos, MD
Athanasios J. Manolis, MD
Asklepeion General Hospital
- © 2011 American Heart Association, Inc.