Accuracy of plethysmographic indices as predictors of fluid responsiveness in mechanically ventilated adults: a systematic review and meta-analysis.

PURPOSE: To systematically review the accuracy of the variation in pulse oxymetry plethysmographic waveform amplitude (∆POP) and the Pleth Variability Index (PVI) as predictors of fluid responsiveness in mechanically ventilated adults. METHODS: MEDLINE, Scopus and the Cochrane Database of Systematic Reviews were screened for clinical studies in which the accuracy of ∆POP/PVI in predicting the hemodynamic response to a subsequent fluid bolus had been investigated. Random-effects meta-analysis was used to summarize the results. Data were stratified according to the amount of fluid bolus (large vs. small) and to the study index (∆POP vs. PVI). RESULTS: Ten studies in 233 patients were included in this meta-analysis. All patients were in normal sinus rhythm. The pooled area under the receiver operating characteristic curve (AUC) for identification of fluid responders was 0.85 [95 % confidence interval (CI) 0.79-0.92]. Pooled sensitivity and specificity were 0.80 (95 % CI 0.74-0.85) and 0.76 (0.68-0.82), respectively. No heterogeneity was found within studies with the same amount of fluid bolus, nor between studies on ∆POP and those on PVI. The AUC was significantly larger in studies with a large bolus amount than in those with a small bolus [0.92 (95 % CI 0.87-0.96) vs. 0.70 (0.62-0.79); p < 0.0001]. Sensitivity and specificity were also higher in studies with a large bolus [0.84 (95 % CI 0.77-0.90) vs. 0.72 (0.60-0.82) (small bolus), p = 0.08 and 0.86 (95 % CI 0.75-0.93) vs. 0.68 (0.56-0.77) (small bolus), p = 0.02], respectively. CONCLUSIONS: Based on our meta-analysis, we conclude that ∆POP and PVI are equally effective for predicting fluid responsiveness in ventilated adult patients in sinus rhythm. Prediction is more accurate when a large fluid bolus is administered.

Diagnostic accuracy of passive leg raising for prediction of fluid responsiveness in adults: systematic review and meta-analysis of clinical studies.

PURPOSE: To systematically review the published evidence on the ability of passive leg raising-induced changes in cardiac output (PLR-cCO) and in arterial pulse pressure (PLR-cPP) to predict fluid responsiveness. METHODS: MEDLINE, EMBASE and the Cochrane Database of Systematic Reviews were screened. Clinical trials on human adults published as full-text articles in indexed journals were included. Two authors independently used a standardized form to extract data about study characteristics and results. Study quality was assessed by using the QUADAS scale. RESULTS: Nine articles including a total of 353 patients were included in the final analysis. Data are reported as point estimate (95% confidence intervals). The pooled sensitivity and specificity of PLR-cCO were 89.4% (84.1-93.4%) and 91.4% (85.9-95.2%) respectively. Diagnostic odds ratio was 89.0 (40.2-197.3). The pooled area under the receiver operating characteristics curve (AUC) was 0.95 (0.92-0.97). The pooled correlation coefficient r between baseline value of PLR-cCO and CO increase after fluid load was 0.81 (0.75-0.86). The pooled difference in mean PLR-cCO values between responders and non-responders was 17.7% (13.6-21.8%). No significant differences were identified between patients adapted to ventilator versus those with inspiratory efforts nor between patients in sinus rhythm versus those with arrhythmias. The pooled AUC for PLR-cPP was 0.76 (0.67-0.86) and was significantly lower than the AUC for PLR-cCO (p < 0.001). The pooled difference in mean PLR-cPP values between responders and non-responders was 10.3% (6.5-14.1%). CONCLUSIONS: Passive leg raising-induced changes in cardiac output can reliably predict fluid responsiveness regardless of ventilation mode and cardiac rhythm. PLR-cCO has a significantly higher predictive value than PLR-cPP.

Are patients brain-dead after successful resuscitation from cardiac arrest suitable as organ donors? A systematic review.

AIM: To compare the outcome of organs retrieved from patients brain dead due to cardiac arrest (CA) with that of organs retrieved from patients brain dead due to other causes (non-CA). METHODS: Systematic review. Clinical studies comparing the outcome of patients and organs retrieved from donors brain dead after being resuscitated from cardiac arrest with that of patients and organs retrieved from donors brain dead not due to cardiac arrest were considered for inclusion. Full-text articles were searched on MEDLINE, EmBASE, Cochrane Register of Controlled Trials and Cochrane Register of Systematic Reviews. MAIN OUTCOME MEASURE: One-year patient or organ survival rate. RESULTS: Four studies fulfilling inclusion criteria were found and three had sufficient quality to be included in final analysis. A total of 858 organs were transplanted from 741 donors. Since the transplanted organs (heart, liver, kidney, lung and intestine) were different in the three studies, metanalysis was not performed. There were no significant differences in 1-year survival rates between CA and non-CA groups. No significant differences were reported for 5-year survival rates, early recovery of transplanted organ function, and organ rejection rates. CONCLUSION: Survival rates of kidneys, livers, hearts and intestines retrieved from CA donors were not significantly different from that of organs transplanted from non-CA donors. Patients brain dead after having been resuscitated from cardiac arrest can be considered as potential donors for organ transplantation.