Evaluation of respiratory status in patients after thoracic esophagectomy using PiCCO system

Thoracic esophagectomy for esophageal cancer is among the most invasive operations, requiring thoracotomy and laparotomy. With regard to postoperative status, the increment of vascular permeability caused by various inflammatory cytokines might influence the postoperative respiratory condition. The PiCCO (pulse contour cardiac output) system (Pulsion Medical Systems AG, Munich, Germany), a new technique based on an arterial thermodilution technique, allows the measurement of extravascular lung water (EVLW). In this study, we hypothesized that EVLW might be a useful parameter to assess the respiratory condition and evaluated respiratory status using values for EVLW after thoracic esophagectomy.

The PiCCO system was established in the intensive care unit (ICU) in 25 patients immediately after thoracic esophagectomy for esophageal cancer. EVLWI (EVLW/body weight, normal range: 3-7 ml/kg) was measured on ICU days (ICUD) 1, 2, and 3. The PaO(2)/FiO(2) (P/F ratio), pulmonary compliance, and lung injury score (LIS) were also calculated, and relationships between EVLWI and those parameters were evaluated.

Mean operating time, blood volume, and fluid balance during surgery were 515+/- 16 (395-690) min, 721+/- 91 (167-1,770) ml, and 3,462+/- 292 (1,892-7,300) ml, respectively. The mean ICU stay was 3.4 +/- 0.3 (2-10) days, and all patients were discharged from the ICU without complications. EVLWI gradually increased after surgery with values of 8.6+/- 1.9 ml/kg on ICUD 1, 9.7+/- 2.7 ml/kg on ICUD 2, and 10.0+/- 3.0 ml/kg on ICUD 3. EVLWI was well correlated with P/F ratio (r = -0.358, p = 0.0135), pulmonary compliance (r = -0.625, p = 0.0001), and LIS (r = 0.614, p = 0.0001).

EVLWI may be a useful parameter for evaluation of the respiratory condition after thoracic esophagectomy.