The effect of sevoflurane on the corrected interval between the Q wave and T wave of the electrocardiogram (QTc) in patients with diabetes mellitus.

The effect of sevoflurane on the corrected QT interval (QTc), QTc dispersion, the interval between peak to end of T wave (Tp-e) and Tp-e/QTc ratio in diabetic and non diabetic women undergoing elective non-laparoscopic surgery requiring general anaesthesia with endotracheal intubation

Status

Completed

Phases

Phase 4

Study type

Interventional

Source

ANZCTR

Registry ID

ACTRN12610000259044

Enrollment

Registered

2010-03-30

Start date

2010-09-30

Completion date

2014-11-25

Last updated

2021-11-29

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

None listed

Brief summary

Sevoflurane is one of the widely used anaesthetic vapours for general anaesthesia. This vapour is delivered to the patients lungs through a breathing tube. It is known to alter the electrical activity of the heart. This manifests as a prolonged QTc interval of the electrocardiogram (ECG). One of the potential dangers associated with this phenomenon is the occurrence of a dangerous irregular heart beat. However, it is a very rare condition. People with diabetes mellitus are more prone to have a prolonged QTc interval due to various reasons. It is not known whether the diabetic patients are at an increased risk of QTc prolongation compared with non diabetics on exposure to sevoflurane anaesthesia. This study tries to look at the impact of sevoflurane on the QTc interval in patients with diabetes mellitus. The primary outcome parameters of interest are the Tp-e interval and Tp-e / QTc ratio of the ECG, as these measures are sensitive in predicting dangerous arrhythmias. The secondary outcome measures of interest are Qtc and QTcd values of the ECG.

Interventions

General anaesthesia with sevoflurane at 1.0 minimum alveolar concentration (MAC) administered through an endotracheal tube in to the patients lungs during the surgical period which is roughly two hours.

Study design

Allocation

Non-randomised trial

Intervention model

Other

Primary purpose

Prevention

Masking

Open (masking not used)

Eligibility

Sex/Gender

All

Age

40 Years to No maximum

Healthy volunteers

Inclusion criteria

Women aged > 40 yr ASA I – III (American society of Anesthesiologists physical status) scheduled for elective non-laparoscopic surgical procedures lasting more than 60 min requiring general anaesthesia with endotracheal intubation would be recruited in this study. Medically managed (both oral hypoglycaemic agents and insulin) diabetic patients with the duration of the disease for atleast two years or those who have atleast one HbA1c (glycosylated haemoglobin) level more than 7% recorded prior to the presentation would be compared with a control group of non diabetic patients.

Exclusion criteria

Patients with a preoperative QTc interval greater than 440ms, having conduction defects and arrhythmias, taking medications affecting the QTc interval , suffering from ischemic heart disease as defined by previous history of angina, myocardial infarction or ischaemic cardiomyopathy, patients with congenital or acquired cardiac defects, preexisting electrolyte imbalances and thyroid and renal dysfunction as defined by the estimated glomerular filtration rate (eGFR) < 60 ml/min/ 1.73m 2 would be excluded. Diabetic patients on diet control and patients with known or suspected family history of malignant hyperthermia would also be excluded

Outcome results