Phase II study comparing nasal pressure monitoring with capnography during invasive endoscopic procedures: a single-center, single-arm trial.

Nasal pressure signal is commonly used to evaluate obstructive sleep apnea. This study aimed to assess its safety for respiratory monitoring during sedation. A total of 45 adult patients undergoing sedation with propofol and fentanyl for invasive endoscopic procedures were enrolled. While both nasal pressure and capnograph signals were continuously recorded, only the nasal pressure signal was displayed. The primary outcome was the incidence of oxygen desaturation below 90%. The secondary outcomes were the ability to predict the desaturation and incidence of harmful events and false alarms, defined as an apnea waveform lasting more than 3 min without desaturation. Of the 45 participants, 43 completed the study. At least one desaturation event occurred in 12 patients (27.9%; 95% confidence interval 15.3-43.7%). In these 12 patients, more than half of the desaturation events were predictable in 9 patients by capnography and 11 patients by nasal pressure monitoring (p = 0.59). In the 43 patients, false alarms were detected in 7 patients with capnography and 11 patients with nasal pressure monitoring (p = 0.427). Harmful events unrelated to nasal pressure monitoring occurred in 2 patients. Nasal pressure monitoring is safe and possibly useful for respiratory monitoring despite false alarms during sedation.

"Salvage techniques" are the key to overcome difficult biliary cannulation in endoscopic retrograde cholangiopancreatography.

Although the efficacy and safety of salvage techniques for biliary cannulation in endoscopic retrograde cholangiopancreatography (ERCP) have been reported, few reports analyzed the choice of techniques and their clinical outcomes in large cohorts. This study aimed to evaluate the outcomes of biliary cannulation in patients with native papillae. We retrospectively identified 1021 patients who underwent initial ERCP from January 2013 to March 2020. We investigated background factors, treatment details, cannulation success rates, and adverse event rates. Then we analyzed a series of treatment processes, including salvage techniques such as double guidewire technique (DGT), needle knife pre-cutting (NKP), and transpancreatic pre-cut papillotomy (TPPP). The initial ERCP success rate using standard technique alone was 62.8%, which increased to 94.3% including salvage techniques. Salvage techniques were frequently required in patients with long oral protrusions (OR 2.38; 95% CI 1.80-3.15; p < 0.001). A total of 503 cases (49.3%) had long oral protrusions, 47.5% of which required the salvage techniques, much higher than 27.5% of not-long cases. Patients with long oral protrusions had a higher frequency of NKP. In conclusion, patients with long oral protrusions frequently required salvage techniques. Salvage techniques may help to overcome many difficult biliary cannulation cases.

Liver cirrhosis is a risk factor for poor prognosis of acute cholangitis caused by choledocholithiasis.

INTRODUCTION AND OBJECTIVES: Acute cholangitis, which is characterized by biliary infection and acute liver injury, may impact cirrhosis prognosis. However, the prognosis itself remains unclear. MATERIALS AND METHODS: This multicenter retrospective cohort study compared the mortality and liver function change between patients with and without cirrhosis who underwent endoscopic treatment for acute cholangitis caused by choledocholithiasis between January 2004 and December 2019. RESULTS: We analyzed 699 patients, 44 of whom had cirrhosis. The cirrhotic group had a significantly higher 30-day mortality rate than the noncirrhotic group (14% vs. 1%; P < 0.001). The cirrhotic group also had significantly lower total bilirubin and albumin recovery. However, all patients with cirrhosis who survived achieved total-bilirubin recovery, and 91% achieved albumin recovery within 90 days. In multivariable Cox regression analysis, the independent risk factors for total-bilirubin recovery included cirrhosis (hazard ratio, 0.37; 95%CI, 0.24‒0.58; P < 0.001) and high total-bilirubin level (0.46; 95%CI, 0.34‒0.60; P < 0.001), whereas those for albumin recovery were cirrhosis (0.51; 95%CI, 0.33‒0.79; P = 0.002), high age (0.62; 95%CI, 0.47‒0.82; P < 0.001), organ dysfunction (0.62; 95%CI, 0.39‒0.96; P = 0.03), low albumin level (0.57; 95%CI, 0.36‒0.91; P = 0.02), and high C-reactive protein level (0.73; 95%CI, 0.56‒0.95; P = 0.02). CONCLUSIONS: Patients with cirrhosis complicated with acute cholangitis had poor prognosis. Recovery of liver function after endoscopic treatment was slow; nevertheless, most patients who survived could recover within 90 days.

Diagnostic value of peroral cholangioscopy in addition to computed tomography for indeterminate biliary strictures.

BACKGROUND: Peroral cholangioscopy (POCS) has been used to overcome the difficulty in diagnosing indeterminate biliary stricture or tumor spread. However, the value of adding POCS to computed tomography (CT) remains unclear. Our aim was to evaluate the diagnostic value of adding POCS to CT for indeterminate biliary stricture and tumor spread by interpretation of images focusing on the high diagnostic accuracy of visual findings in POCS. METHODS: We retrospectively identified 52 patients with biliary stricture who underwent endoscopic retrograde cholangiography (ERC) at our institution between January 2013 and December 2018. Two teams, each composed of an expert endoscopist and surgeon, performed the interpretation independently, referring to the CT findings of the radiologist. The CT + ERC + POCS images (POCS group) were evaluated 4 weeks after the evaluation of CT + ERC images (CT group). A 5-point scale (1: definitely benign to 5: definitely malignant) was used to determine the confident diagnosis rate, which was defined as an evaluation value of 1 or 5. Tumor spread was also evaluated. RESULTS: In the evaluation of 45 malignant diagnoses, the score was significantly closer to 5 in the POCS group than in the CT group in both teams (P < 0.001). The confident diagnosis rate was significantly higher for the POCS group (92% and 73%) than for the CT group (25% and 12%) in teams 1 and 2, respectively (P < 0.001). We found no significant difference in diagnostic accuracy for tumor spread between the groups. CONCLUSION: Visual POCS findings confirmed the diagnosis of biliary strictures. POCS was useful in cases of indefinite diagnosis of biliary strictures by CT.

Analysis of circulating cell-free DNA after endoscopic ultrasound-guided fine needle aspiration in pancreatic ductal adenocarcinoma.

BACKGROUND/OBJECTIVES: Recently, increase in cell-free DNA (cfDNA) concentration or newly detected KRAS mutation after endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) biopsy were reported to be related to the occurrence of new distant metastasis. In this study, we investigated whether cfDNA concentration increased with the release of tumor components into the blood after EUS-FNA and whether its increase was related to prognosis. METHODS: Sixty-eight patients underwent EUS-FNA and were pathologically confirmed as having pancreatic ductal adenocarcinoma (PDAC). We measured plasma cfDNA concentration and the copy number of KRAS mutation in 68 patients and circulating tumor cells in 8 before and after EUS-FNA. RESULTS: The average cfDNA concentration after EUS-FNA (672.5 ± 919.6 ng/mL) was significantly higher than that before EUS-FNA (527.7 ± 827.3 ng/mL) (P < 0.001). KRAS mutation in plasma was detected in 8 patients (11.8%), however a significant increase in cfDNA concentration after EUS-FNA was not related to the change in KRAS-mutant copy number. Minimal increase in circulating tumor cells was observed in 3 of 8 patients. New distant metastasis was observed within 286 days to initial metastasis detection in 6 of 12 patients with ≥2-fold increase in cfDNA concentration and 26 of 56 patients with <2-fold increase within 185 days. In 32 patients who underwent surgery, ≥2-fold increase in cfDNA did not affect early recurrence. CONCLUSIONS: The increase in cfDNA concentration after EUS-FNA was not caused by tumor cell components released into blood vessels. Hence, the risk of seeding via the blood stream after EUS-FNA may need not be considered.