Hemodynamic Effects of Lidocaine in the Thoracic Paravertebral Space During One-Lung Ventilation for Thoracic Surgery

Objective: There is increasing interest in the use of the thoracic paravertebral block (TPVB) in association with general anesthesia for lung-resection surgery. The aim of the study was to evaluate the hemodynamic effects of a 5-mg/kg lidocaine bolus injected in the thoracic paravertebral space during one-lung ventilation (OLV) in noncardiac patients undergoing thoracic surgery.Design: Prospective, observational study.Setting: Tertiary care university hospital.Participant: Twenty patients undergoing thoracotomy for lung resection.Interventions: In addition to standard monitoring, cardiac output, preload parameters (global diastolic volume, total intrathoracic blood volume, and systolic volume variation), and myocardial contractility (dPmax and cardiac function index) were measured with an aortic transpulmonary thermodilution technique.Measurements and Main Results: After OLV initiation, a paravertebral lidocaine bolus of 5 mg/kg (2%) caused decreases in the dPmax and cardiac function index that lasted up to 30 minutes. Accompanying minor reductions in heart rate and systolic blood pressure required no vasoactive drugs and were self-limiting. None of the other hemodynamic parameters studied was significantly altered.Conclusions: In noncardiac patients, TPVB is associated with good hemodynamic stability, despite a small and transient decrease in myocardial contractility that could be related to the drug’s systemic effects after its absorption.