Changes in stroke volume variation monitored by FloTrac/Vigileo system during mechanical ventilation in patients undergoing pulmonary lobectomy

Abstract

Objective To investigate the changes in stroke volume variation (SVV) monitored by FloTrac/Vigileo system during mechanical ventilation in patients undergoing pulmonary lobectomy.Methods Forty-four ASA Ⅰ or Ⅱ patients aged 44-64 yr weighing 47-86 kg undergoing elective pulmonary lobectomy performed under general anesthesia were studied.Blood volume was maintained by fluid (crystalloid∶ colloid 1∶1) infusion at a rate of 6-8 ml·kg-1 ·h-1.Cardiac output index (CI),stroke volume index (SVI) and SVV were measured based on arterial pressure wave form analysis by FloTrac/Vigileo System (Edwards Co.,USA) and recorded at following time points:at 5 min of two-lung ventilation (TLV) in supine position,2 min TLV in lateral position,during one-lung ventilation (OLV) before thoracotomy,at 5 and 30 min of OLV after thoracotomy,1 and 15 min OLV + PEEP of 5cm H2 O,before and immediately and 1 min after reflation of the remaining lobes.The normal value for SVV is less than 13％.Results The hemodynamic parameters were stable during lobectomy.CI and SVI were within normal range.SVV was less than 13％ at all time points except that at immediately after reflation of the remaining lobes.Conclusion SVV obtained with FloTrac/Vigileo system can be used to guide fluid therapy during OLV in mechanically ventilated patients undergoing pulmonary lobectomy. Key words: Stroke volume; Respiration, artificial; Pneumonectomy