title: Acquired QT interval changes and neck dissections.
abstract: OBJECTIVE
  To determine if acquired long QT syndrome following right or left, radical or modified, neck dissections result in malignant arrhythmias or deaths.
  
  
  METHODS
  Prospective study.
  
  
  METHODS
  Inpatient head and neck service of the Massachusetts Eye and Ear Infirmary.
  
  
  METHODS
  69 patients who underwent extensive neck surgery, without congenital long QT syndrome, medications known to prolong the QT interval, preoperative ventricular arrhythmias, or electrolyte abnormalities.
  
  
  METHODS
  None.
  
  
  RESULTS
  Preoperative and postoperative electrolytes were evaluated. Preoperative and postoperative electrocardiograms and QT intervals were evaluated. Continuous intraoperative and 10- to 12-hour postoperative monitoring of lead II or V5 were evaluated. Twenty-six patients (Group 1) underwent either right radical neck dissection or modified right radical neck dissection, 25 patients (Group 2) underwent either left radical neck dissection or modified left neck dissection, and 18 patients (Group 3) underwent extensive neck surgery without radical or modified neck dissection. Postoperatively, 38 patients (19 Group 1, 11 Group 2, and 8 Group 3 patients) developed a QT interval corrected for heart rate (QTc) of greater than 440 milliseconds. Repeated measures analysis of variance, comparing preoperative and postoperative QTc showed a statistically significant preoperative to postoperative change, but no significant difference among the three groups. No malignant arrhythmias or deaths were recorded in any of the three groups.
  
  
  CONCLUSIONS
  Acquired long QT syndrome following radical neck dissection, without congenital, metabolic, or pharmacologic disturbance, is unlikely to trigger malignant arrhythmias, as previously reported for right radical neck dissection.
authors.affiliation: Department of Anesthesia, Massachusetts Eye and Ear Infirmary, Boston 02114, USA.
authors.forename: M A
authors.initials: MA
authors.lastname: Acquadro
authors.forename: T X
authors.initials: TX
authors.lastname: Nghiem
authors.forename: T P
authors.initials: TP
authors.lastname: Beach
authors.forename: J V
authors.initials: JV
authors.lastname: Donlon
authors.forename: M P
authors.initials: MP
authors.lastname: Joseph
authors.forename: D K
authors.initials: DK
authors.lastname: Ahern
mesh_terms: D000704:Analysis of Variance; D000762:Anesthesia Recovery Period; D001145:Arrhythmias, Cardiac / Q000209:etiology; D002118:Calcium / Q000032:analysis; D002423:Cause of Death; D004562:Electrocardiography; D015716:Electrocardiography, Ambulatory; D005260:Female; D006339:Heart Rate; D006801:Humans; D008133:Long QT Syndrome / Q000209:etiology*; D008197:Lymph Node Excision / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative; D009333:Neck / Q000601:surgery*; D037981:Neck Dissection / Q000009:adverse effects*; D011182:Postoperative Care; D011188:Potassium / Q000032:analysis; D011446:Prospective Studies
chemical_list: D011188:Potassium; D002118:Calcium