Hands off Trans-Femoral Venous Intra-Abdominal Pressure Estimates in Children: Results of a Sobering Single-Center Study

BACKGROUND

For a long time, trans-femoral venous pressure (FVP) measurement was considered a simple alternative for estimating intra-abdominal pressure (IAP). Since intravesical [IVP] and intragastric [IGP] pressure measurements are sometimes contraindicated for anatomical and pathophysiological reasons, FVP raised hopes, especially among pediatricians. Pediatric FVP validation studies have never been published; recent results from adult studies cast doubt on their interchangeability. Therefore, we compared for the first time the measurement agreement between FVP and IVP and IGP in children.

MATERIAL AND METHODS

We prospectively compared FVP with IVP and IGP, according to the Abdominal Compartment Society validation criteria. Additionally, we analyzed the agreement as a function of IAP or right heart valve regurgitation and pulmonary hypertension.

RESULTS

In a real-life PICU study design, n = 39 children were included (median age 4.8 y, LOS-PICU 23 days, PRISM III score 11). In n = 660 FVP-IGP measurement pairs, the median IAP was 7 (range 1 to 23) mmHg; in n = 459 FVP-IVP measurement pairs, the median IAP was 6 (range 1to 16) mmHg. The measurement agreement was extremely low with both established methods (FVP-IGP: r² 0.13, mean bias -0.8 ± 4.4 mmHg, limits of agreement (LOA) -9.6/+8.0, percentage error (PE) 55%; FVP-IVP: r² 0.14, bias +0.5 ± 4.2 mmHg, limit of agreement (LOA) -7.9/+8.9, percentage error (PE) 51%). No effect of the a priori defined influencing factors on the measurement agreement could be demonstrated.

CONCLUSIONS

In a study cohort with a high proportion of critically ill children suffering from IAH, FVP did not agree reliably with either IVP or IGP. Its clinical use in critically ill children must therefore be strongly discouraged.

Performance of a six-methylation-marker assay on self-collected cervical samples - A feasibility study

OBJECTIVES

In high-income countries, a high proportion of cervical cancers is diagnosed in screening non-attendees. One approach to improve screening coverage is to offer self-sampling for human papillomavirus (HPV) testing. However, especially young women are often HPV positive without having a precancerous lesion in need of treatment. To improve the rather low specificity of HPV testing additional markers such as DNA-methylation can be used. The aim of this feasibility study was to examine the performance of the methylation marker assay GynTect®, comprising six methylation markers, on dry self-collected cervico-vaginal samples compared to physician-taken samples.

METHODS

We recruited 89 patients from our colposcopy clinic of whom 87 qualified for the study. The women took a self-sample with the Evalyn-Brush. Afterwards the planned colposcopy was performed and smears for cytology and reference HPV testing were taken as well as a biopsy in cases of abnormalities. Physician-taken and self-collected samples were tested for HPV DNA and were analyzed with GynTect®.

RESULTS

We obtained 95.5 % valid results for the self-collected samples which was very close to the physician-taken samples. Only about half of the self-collected samples were GynTect® positive in comparison to the physician-taken samples. GynTect® scores were significantly lower for self-collected than for physician-taken samples (p = 0.001, paired t-test). The overall concordance for GynTect® results was moderate (kappa 0.394; p < 0.001). For HPV testing we obtained a good concordance (kappa 0.586; p < 0.001). The GynTect® results for the self-collected samples showed a sensitivity for the detection of cervical intraepithelial neoplasia 2 or worse (CIN2+) of 26.1 % (95 %-CI: 0.13-0.46) and a specificity of 95.6 % (95 %-CI: 0.85-0.99), in comparison to a sensitivity of 45.5 % (95 %-CI: 0.27-0.65) and a specificity of 78.3 % (95 %-CI: 0.64-0.88) for the physician-taken samples.

CONCLUSIONS

GynTect® methylation marker testing has a satisfactory amount of valid results on self-collected samples. However, the results of the self-collected samples differed clearly in comparison to the reference samples. To justify an application in screening, a larger study with more cases of high-grade cervical dysplasia and HPV positive patients will be needed.