This retrospective study was conducted in accordance with the Ethical Guidelines of the Declaration of Helsinki. This study was approved by the Institutional Review Board of Chonnam National University Hospital (no. CNUH-2018-236).
From October 2008 to December 2017, a total of 4475 consecutive patients underwent endoscopic resection of gastric epithelial neoplasms in our center. Among them, 242 aged 75 years or older were included in this study. The patients underwent ESD or EMR for gastric epithelial neoplasms. We reviewed their medical records and extracted information about their demographic and clinical characteristics, procedural outcomes, and procedure- or sedation-related complications.
Assessment of CCI scores before endoscopic procedure
The components of CCI include: previous myocardial infarction, congestive cardiac failure, peripheral vascular disease, cerebrovascular accident, dementia, chronic obstructive pulmonary disease, connective tissue disease, peptic ulcer disease, diabetes, renal disease, hemiplegia, leukemia, lymphoma, solid tumor with or without metastatic disease, liver disease, and acquired immunodeficiency syndrome status. We calculated the CCI by summing the weights of all comorbid parameters. The total CCI score was 0-33. We divided the patients into those with a CCI < 3 and those with a CCI ≥ 3.
We reviewed the patients’ medical records to investigate their social history, body mass index, and comorbidities. Based on these data, the performance status of all enrolled patients was evaluated using the American Society of Anesthesiologists-Performance Status and Eastern Cooperative Oncology Group-Performance Status.
Endoscopists determined the methods of removal for the lesions (EMR or ESD) according to shape, size, presence of fibrosis, or presence of lesion ulceration before endoscopic resection. For ESD or EMR, patients were placed in the left lateral decubitus position. Each endoscopic procedure was performed using a single-channel upper gastrointestinal endoscope with transparent hood under CO2 insufflation.
Anticoagulants or antiplatelet agents
Anticoagulant and antiplatelet agent therapy was discontinued for endoscopic resection according to the recommended cessation period . The endoscopic procedure was evaluated as a high risk procedure that could cause bleeding, and the discontinuation of the drug was determined individually according to the patient's pre-existing thromboembolic condition.
All procedures were performed with use of endoscopist-directed sedation. Patients were sedated with midazolam and pethidine with or without propofol. The target sedation level was mild to moderate . For sedation induction, midazolam 3 mg and pethidine 25 mg were intravenously injected. Thereafter, additional propofol, midazolam, or pethidine was intravenously injected to ensure adequate sedation or pain control. Oxygen was supplied at a constant level of 2 L/min via a nasal prong during the procedure, and sedative medication doses were adjusted according to the vital signs of patients. We monitored blood pressure, heart rate, and oxygen saturation during the procedure.
The primary outcome was procedure- and sedation-related complications, while the secondary outcomes were procedure time and complete resection rate.
Procedure-related bleeding was defined as bleeding requiring transfusion or emergency endoscopy or that reduced the hemoglobin level by more than 2 g/dL following the procedure. We defined immediate bleeding as bleeding occurring within 24 hours after the endoscopic resection and delayed bleeding as gastrointestinal bleeding occurring later than 24 hours after the endoscopic resection [20, 21]. Procedure-related perforation was defined as endoscopically observed extraluminal space or intra-abdominal free air on chest radiography taken after the procedure .
Sedation-related complications were divided into immediate complications (hypotension, arrhythmia, hypoxia) during endoscopy and post-procedural complications (respiratory complications such as atelectasis and pneumonia).
Hypotension during the procedure was defined as systolic blood pressure below 90 mmHg. Oxygen desaturation was defined as oxygen arterial saturation < 90% for at least 10 seconds. Supplemental oxygen was given to maintain oxygen arterial saturation > 90%. Bradycardia was defined as any episode of heart rate < 40 beats per minute.
All patients underwent pre-procedure chest radiography at the time of admission. Atelectasis was diagnosed by comparison of post-procedure and pre-procedure chest radiographic findings, regardless of clinical symptoms. Radiographic findings of atelectasis include direct signs such as crowding of pulmonary vessels, crowed air bronchogram, and displacement of interlobar fissure as well as indirect signs such as pulmonary opacification and elevation of the ipsilateral diaphragm. Pneumonia was defined as newly developed pulmonary infiltration with clinical symptoms such as cough, sputum, and fever with chilling. In these cases, proper antibiotics were administered.
Procedure time was defined as the time from the start of intravenous administration of the sedative agent to the time of endoscope extubation.
Complete resection was defined as follows: 1) tumor removed in one piece (en bloc resection) and horizontal/vertical margin was histologically free from tumorous glands; or 2) tumor removed in multiple pieces (piecemeal resection) and follow-up endoscopy revealed no recurrence for at least 1 year.
Follow up endoscopy
Follow-up endoscopy was performed 3-6 months after endoscopic resection, and follow-up endoscopy was performed every year thereafter. We defined tumor recurrence as local recurred or metachronous lesions in the stomach after 1 year after endoscopic resection of the primary lesion.
Statistical analysis was performed using SPSS version 23.0 (SPSS Inc., Chicago, IL, USA). Continuous data are shown as mean ± standard deviation or median (range), while categorical data are shown as absolute and relative frequencies. Continuous variables were analyzed using Student’s t-test. Categorical data were examined using Fisher’s exact test or the chi-squared test. On multivariate analysis, binary logistic regression models with forward conditioning were used to investigate CCI-associated complications. The data included in the regression analysis are presented as crude or adjusted odds ratios with 95% confidence intervals (CIs). Variables with P values < 0.05 on the univariate analysis were selected for inclusion in the multivariate analysis.