Elevated PPV predicts increased LOS and morbidity in high risk abdominal surgery

Patient Population
High risk abdominal & bariatric surgery.

LiDCO Monitor
LiDCOrapid fluid optimisation.

Trial Design
Prospective observational study.  Maintaining a threshold of 13% for PPV% was deemed adequate fluid management.

Outcome Impact
Patients with PPV maintained at threshold had decreased LOS (10.1 to 6.1 days) and a reduction in postoperative complication rates.

High-risk abdominal surgery has been reported to have patient morbidity between 20-40% and a mortality of up to 10%. Intraoperative fluid resuscitation has been shown to reduce morbidity and hospital length of stay (LOS). Functional hemodynamic parameters are sensitive and specific for fluid responsiveness and could be effective to guide intraoperative goal-directed therapy. We performed a prospective observational study to evaluate the effect of LOS in high-risk abdominal surgery patients with adequate resuscitation, based on the percent of intraoperative time that the patient spent below a PPV threshold of 13%.

After IRB approval and informed consent, 28 patients of ASA class 2-4 scheduled for major elective intra-abdominal surgery (with potential EBL of 500+cc) were enrolled in this prospective observational trial conducted between 9/2009 and 3/2010. Exclusion criteria were patients with arrhythmias, CHF, or hemodynamically significant heart disease, and patients with intraoperative massive transfusion. Of the 28 patients enrolled, 3 were excluded due to ASA status, unrecorded data (equipment malfunction) and massive transfusion. After induction of GA, a radial arterial line was placed. Hemodynamic values were recorded using the LIDCOrapid. At case termination, audit values of PPV threshold >13% were utilized for analysis as determined by LIDCOview Pro software. All patients were followed prospectively. Patients were divided into adequate resuscitation and inadequate resuscitation groups based on the percent of intraoperative time spent above or below a PPV threshold of 13%. Adequate resuscitation was defined as less than or equal to 25% of intraoperative time spent above a PPV threshold value of 13%. Inadequate resusciation was defined as >25% of intraoperative time spent above a PPV threshold of 13%. The primary analysis was to evaluate for differences in LOS between groups. Secondary anlaysis included a reduction of postoperative complication rates including PONV, cardiac, renal or bowel dysfunction, and mortality if present. Data was analyzed utilizing an un-paired t-test, chi square or fisher’s exact test as appropriate. A p-value of <0.05 was considered significant.


In patients that had adequate resuscitation a significant decrease in LOS was observed from 10.1 to 6.1 days respectively (p<.02 95% CI=-7.20 to -0.79). The adequate resuscitation group had a reduction in postoperative complication rates 7 vs. 1 (P= 0.03). No significant difference was noted between groups with regard to case duration, EBL, crystalloid (5.7 vs. 5.6 l) or colloid administration (0.917 vs. 1.0 l), age, gender or ASA status. There was one patient mortality in the inadequate resuscitation group but this was not statistically significant.

A significant decrease in LOS was noted in the adequate resuscitation group based on PPV threshold audit analysis of 25% case duration. This group also had a reduction in post-operative complications. Further study utilizing this and other functional hemodynamic parameters to guide intraoperative fluid resuscitation should be performed and could improve the quality and safety of healthcare delivery to these patients.