Effect of increasing age on the haemodynamic response to thoracic epidural anaesthesia An observational study

BACKGROUND Sympathetic blockade with thoracic epidural anaesthesia (TEA) results in circulatory changes and may directly alter cardiac function. Ageing is associated with an impairment of autonomic nervous system control and a deterioration of myocardial diastolic performance. OBJECTIVES We postulated that haemodynamic changes induced by TEA could vary with age. DESIGN An observational study. SETTINGS Tertiary, university hospital. PATIENTS Thirty- five patients scheduled for pulmonary surgery and TEA stratified into three age groups: 18 to 45 years; 46 to 65 years; and at least 66 years. INTERVENTIONS Cardiac performance was evaluated in awake patients using transthoracic echocardiography (TTE) at baseline and 45 min after institution of TEA. Intravenous volume loading was used to preserve preload. MAIN OUTCOME MEASURES Tissue Doppler imaging (TDI) and other derived indices from TTE were used to quantify biventricular systolic and diastolic function. RESULTS Baseline systolic and diastolic left ventricular function and right ventricular diastolic function decreased with age. After TEA, mean arterial pressure ( MAP) decreased (91.2 vs. 79.2 mmHg; P< 0.001) and cardiac index increased (2.7 vs. 3.0 l min - (1)m- 2; P= 0.005), although heart rate and Doppler- derived indices of left ventricular contractility remained unchanged. Right ventricular ejection indices increased and TDI- derived measures of diastolic performance increased for the left ventricle (LV) as well as the right ventricle (RV). With the exception of Tricuspid Annular Plane Systolic Excursion (TAPSE), which increased with increasing age (R=0.53; P= 0.003), TEA effects on biventricular function were not influenced by age. CONCLUSION When preload is preserved with volume loading, TEA predominantly causes systemic vasodilatation and increases global haemodynamic performance. Indices of left ventricular systolic function do not change, whereas left ventricular and right ventricular diastolic function appears to improve. The effects of TEA on right ventricular systolic function are inconclusive. Although increasing age causes a consistent decline of baseline diastolic function, the cardiovascular response to TEA is not impaired in the elderly.