Bradycardia, also known as bradyarrhythmia, is a slow heart rate, namely, a resting heart rate of under 60 beats per minute (BPM) in adults.It is a type of cardiac arrhythmia. It seldom results in symptoms until the rate drops below 50 BPM
Bradycardia can cause dizziness, weakness, lack of energy or fainting spells.If bradycardia is caused by a medical illness, there will be additional symptoms that are specific to that illness. For example, people whose bradycardia is due to severe hypothyroidism also can have constipation, muscle cramps, weight gain (often despite poor appetite), very dry skin, hair that is thin and dry, an abnormal sensitivity to cold temperatures and other symptoms related to low levels of thyroid hormones.
Preoperatively hypotension developed in 85 patients (2.8%), and bradycardia in 54 patients (4.5%). Intraoperatively, hypotension was observed in 380 patients (31.6%), and bradycardia in 153 patients (12.7%). Hypotension and bradycardia were not influenced by the type of surgical procedure, the type of maintenance of general anaesthesia (inhalational versus total intravenous general anaesthesia) and the level of epidural block (lumbar versus thoracic); but they were more frequent in patients with ASA physical status II and III-IV compared to patients with ASA physical status I (p < 0.05). Prophylactic volume preload decreased the incidence of hypotension from 41.5% to 22.4% (p < 0.0001), while prophylactic atropine before epidural block did not affect the incidence of bradycardia. Patients receiving epidural clonidine showed an increased incidence of intraoperative bradycardia compared to those who did not receive it (p < 0.0001).Randomized, controlled studies should be advocated in order to compare the incidence of hypotension and bradycardia during integrated anaesthesia and during epidural block alone. Our results demonstrated that the use of integrated epidural/general anaesthesia produces an incidence of perioperative hypotension and bradycardia similar to that reported when central blocks are used alone