Evolutionary changes in the electrocardiogram of severe progressive hypothermia

Thompson, Robert; Rich, John Martin; Chmelik, Frank; Nelson, William E.

doi:10.1016/s0022-0736(77)80034-4

Cited by 63 publications

(19 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…7 Subsequent studies found no relationship between the pH, Na ϩ , K ϩ , or Cl Ϫ serum concentrations and the presence of the ''J deflection.'' 15,[26][27][28] The J wave seemed to represent unequal depolarization and repolarization. 19 In addition to the studies in animals, early studies in humans of changes in cardiac conduction showed that drinking iced water resulted in a decrease in the height of the T wave in lead II and inversion of the T wave in lead III.…”

Section: Discussionmentioning

confidence: 99%

A Prospective Evaluation of the Electrocardiographic Manifestations of Hypothermia

Vassallo

Delaney

Hoffman

et al. 1999

Academic Emergency Medicine

View full text Add to dashboard Cite

Abstract. Objective: To determine the effects of body temperature, ethanol use, electrolyte status, and acid-base status on the electrocardiograms (ECGs) of hypothermic patients. Methods: Prospective, two-year, observational study of patients presenting to an urban ED with temperature Յ95ЊF (Յ35ЊC). All patients had at least one ECG obtained. Electrocardiograms were interpreted by a cardiologist blinded to the patient's temperature. J-point elevations known as Osborn waves were defined as present if they were at least 1 mm in height in two consecutive complexes. Results: 100 ECGs were obtained in 43 patients. Presenting temperatures ranged between 74ЊF and 95ЊF (23.3ЊC-35ЊC). Initial rhythms included normal sinus (n = 34), atrial fibrillation (n = 8), and junctional (n = 1). Osborn waves were present in 37 of 43 initial ECGs. Of the six initial ECGs that did not have Osborn waves present, all were obtained in patients whose temperatures were Ն90ЊF (Ն32.2ЊC). For the entire group, the Osborn wave was significantly larger as temperature decreased (p = 0.0001, r = Ϫ0.441). The correlation between temperature and size of the Osborn wave was strongest in six patients with four or more ECGs (range r = Ϫ0.644 to r = Ϫ0.956, p = 0.001). No correlation could be demonstrated between the height of the Osborn waves and the serum electrolytes, including sodium, chloride, potassium, bicarbonate, BUN, creatinine, glucose, anion gap, and blood ethanol levels. Conclusions: The presence and size of the Osborn waves in hypothermic patients appear to be a function of temperature. The magnitude of the Osborn waves is inversely correlated with the temperature. Key words: hypothermia, electrocardiograph; Osborn waves. AC-ADEMIC EMERGENCY MEDICINE 1999; 6:1121-1126 T HE EFFECTS of hypothermia on cardiac conduction were first described in 1892.1 Since then, observations of the physiologic changes that occur with cooling of the heart have been reported in animals 2-14 and in humans undergoing craniotomy for subarachnoid hemorrhage, 15 surgery for cardiac anomalies, [16][17][18][19] and anti-cancer therapy. 20,21The first observation of the changes in the electrocardiogram (ECG) in a patient with unintentional hypothermia was reported in 1938. 22 In the following study, the changes in the ECGs of patients with unintentional hypothermia presenting to a large urban hospital ED are described, and the relationship of these changes to common laboratory parameters are analyzed. A review of the literature focuses on the development of the understanding of the effects of cold on the electrical conduction system of the heart and the resultant physiologic and ECG alterations. METHODSStudy Design. This was a prospective, two-year observational study of hypothermia patients presenting to an urban ED. The study was approved by the institutional review boards of New York University School of Medicine, Bellevue Hospital, and the New York City Health and Hospital Corporation.Study Setting and Population. For the purposes of this study, patients were sele...

show abstract

Section: Discussionmentioning

confidence: 99%

A Prospective Evaluation of the Electrocardiographic Manifestations of Hypothermia

Vassallo

Delaney

Hoffman

et al. 1999

Academic Emergency Medicine

View full text Add to dashboard Cite

show abstract

“…Hypothermia has well-documented effects on the adult cardiovascular system [4][5][6] . The cited randomized controlled trials [1][2][3] involving newborns with moderate to severe HIE report a reversible slowing of the heart rate with cooling.…”

mentioning

confidence: 99%

Changes in the PQRST Intervals and Heart Rate Variability Associated with Rewarming in Two Newborns Undergoing Hypothermia Therapy

et al. 2009

View full text Add to dashboard Cite

Background: Little is known about the effects of hypothermia therapy and subsequent rewarming on the PQRST intervals and heart rate variability (HRV) in term newborns with hypoxic-ischemic encephalopathy (HIE). Objectives: This study describes the changes in the PQRST intervals and HRV during rewarming to normal core body temperature of 2 newborns with HIE after hypothermia therapy. Methods: Within 6 h after birth, 2 newborns with HIE were cooled to a core body temperature of 33.5°C for 72 h using a cooling blanket, followed by gradual rewarming (0.5°C per hour) until the body temperature reached 36.5°C. Custom instrumentation recorded the electrocardiogram from the leads used for clinical monitoring of vital signs. Generalized linear mixed models were calculated to estimate temperature-related changes in PQRST intervals and HRV. Results: For every 1°C increase in body temperature, the heart rate increased by 9.2 bpm (95% CI 6.8–11.6), the QTc interval decreased by 21.6 ms (95% CI 17.3–25.9), and low and high frequency HRV decreased by 0.480 dB (95% CI 0.052–0.907) and 0.938 dB (95% CI 0.460–1.416), respectively. Conclusions: Hypothermia-induced changes in the electrocardiogram should be monitored carefully in future studies.

show abstract

“…Below 33°C the ECG commonly shows a J point elevation that is characteristic in appearance (Figure). As temperature drops, the J wave increases in prominence and is almost always clearly present at core temperatures below 25°C [57,58]. Vectorcardiography reveals that the spatial orientation of the J wave is anterior and leftward, explaining its prominence in the mid and lateral precordial leads [59].…”

Section: Pathophysiolo~ymentioning

confidence: 95%

“…In hypothyroidism, rewarming may increase oxygen demand at a faster rate than the institution of hormone therapy can restore metabolism and thereby precipitate cardiovascular collapse. Patients with myxedema, however, may not respond to slower passive rewarming techniques even if adequate thyroid hormone supplements are provided [57]. If temperature fails to rise adequately despite 12 hours of passive rewarming and hormone therapy, active rewarming should be started.…”

Section: Treatmentmentioning

confidence: 99%

Disorders of Temperature Control: Hypothermia, Part III

Curley

Irwin

1986

J Intensive Care Med

View full text Add to dashboard Cite

Hypothermia, defined as a body core temperature below 35°C, results from exposure to cold, drugs, metabolic dysfunction, or nervous system or skin disorders. The diagnosis and clinical assessment of patients with hypothermia should be based on a thorough knowledge of the characteristic physiologic changes that accompany hypothermia and affect all organ systems. Morbidity and mortality resulting from hypothermia may be reduced when physicians anticipate the well-known complications of hypothermia and carefully rewarm the patient.The rate and method of rewarming must be individualized, taking into account available resources and the patient's cardiopulmonary status and underlying disease.In Parts I and II of this review, the normal physiology of temperature regulation and three hvperthermic syndromes-heat stroke, malignant hyperthermia, and neuroleptic malignant syndrome-were reviewed. This section focuses on unintentional hypothermia and reviews in detail its pathogenesis, pathophysiologic factors, diagnosis, and management. Iatrogenic and intentional hypothermia in the perioperative setting is briefly discussed.Hypothermia, defined as a core temperature below 35°C, is not uncommon; it occurs at all ambient temperatures and in patients of all ages, although more commonly in the elderly. During the winter in Great Britain, 0.7% of all hospital admissions [1], 3% of elderly patients admitted [2], and at least 10% of otherwise healthy elderly individuals examined at home [3] had core temperatures in the hypothermic range. Review of death certificates in the United States reveals an average mortality rate for hypothermia of 0.22 per 100,000 individuals; white women have the lowest rates, and nonwhite men, the highest [4]. When all data are reviewed, the overall mortality from hypothermia in the United States has been conservatively estimated at 17 deaths per million of the general population peryear {5]. The mortality rate for treated hypothermia ranges from 12% [6] to 73% [7]. Cause and PathogenesisAlthough hypothermia can occur in all climates, at nearly all ambient temperatures, and at every age, the most frequent causes (vide infra) appear to be exposure, use of depressant drugs, and hypoglycemia. The elderly, because of a &dquo;normal&dquo; impairment of regulatory function, constitute a large portion of the patients who become hypothermic. A brief review of the causes of hypothermia (Table 1) at UNIVERSITE LAVAL on July 1, 2015 jic.sagepub.com Downloaded from 271 Table 1. Causes of Hypothermia and their pathogenesis will help develop a rational approach to treatment.Exposure to Cold Fatal hypothermia occurs frequently, even in the healthy young adult who simply has been overexposed to the elements. Wet, wind, and exhaustion contribute to increased loss of body heat. Wet clothing loses 90% of its insulating value [8], rendering soaked individuals effectively nude. Exposure to rain or snow was believed to contribute greatly to the development of hypothermia in 15 of 23 incidents in hikers discussed in one rev...

show abstract

Evolutionary changes in the electrocardiogram of severe progressive hypothermia

Cited by 63 publications

References 13 publications

A Prospective Evaluation of the Electrocardiographic Manifestations of Hypothermia

A Prospective Evaluation of the Electrocardiographic Manifestations of Hypothermia

Changes in the PQRST Intervals and Heart Rate Variability Associated with Rewarming in Two Newborns Undergoing Hypothermia Therapy

Disorders of Temperature Control: Hypothermia, Part III

Contact Info

Product

Resources

About