Procollagen I and III as Prognostic Markers in Patients Treated with Extracorporeal Membrane Oxygenation: A Prospective Observational Study

Abstract

Background: Procollagen peptides have been associated with lung fibroproliferation and poor outcomes in patients with acute respiratory distress syndrome (ARDS). Therefore, serum procollagen concentrations might have prognostic value in ARDS patients treated with extracorporeal membrane oxygenation (ECMO). Methods: In a prospective cohort study, serum N-terminal procollagen I-peptide (PINP) and N-terminal procollagen III-peptide (PIIINP) concentrations in twenty-three consecutive patients with severe ARDS treated with ECMO were measured at the time of ECMO initiation and during the course of treatment. The predictive value of PINP and PIIINP at the time of ECMO initiation was tested with a univariable logistic regression and a receiver operating characteristic (ROC) curve analysis. Results: Thirteen patients survived to intensive care unit (ICU) discharge. Non-survivors had higher serum PINP and PIIINP concentrations at all points in time during the course of treatment. Serum PIIINP at the day of ECMO initiation showed an odds ratio of 1.37 (95% CI 1.10-1.89, p = 0.017) with an area under the receiver operating characteristic (ROC) curve (AUC) of 0.87 (95% CI 0.69-1.00, p = 0.0029) for death during the course of treatment. Conclusions: PINP and PIIINP concentrations differ between survivors and non-survivors in ARDS treated with ECMO. This exploratory hypothesis generating study suggests an association between PIIINP serum concentrations at ECMO initiation and an unfavorable clinical outcome.

Keywords: acute respiratory distress syndrome; extracorporeal membrane oxygenation; procollagen I; procollagen III.

Figure 1

N-terminal procollagen I-peptide. Survivor vs. non-survivor, box plots using the Tukey method; PINP, N-terminal procollagen I-peptide. Outliers are marked as circles.

Figure 2

N-terminal procollagen III-peptide. (A) survivor vs. non-survivor, box plots using the Tukey method; (B) ROC curve for PIIINP at the time of ECMO initiation, PIIINP, N-terminal procollagen III-peptide; AUC, area under the ROC curve; ROC, Receiver operating characteristic; ECMO, extracorporeal membrane oxygenation. Outliers are marked as circles.