The use of carbon dioxide for insufflation during GI endoscopy: a systematic review

Nomogram to predict gas-related complications during transoral endoscopic resection of upper gastrointestinal submucosal lesions

BACKGROUND

Gas-related complications present a potential risk during transoral endoscopic resection of upper gastrointestinal submucosal lesions. Therefore, the identification of risk factors associated with these complications is essential.

AIM

To develop a nomogram to predict risk of gas-related complications following transoral endoscopic resection of the upper gastrointestinal submucosal lesions.

METHODS

We collected patient data from the First Affiliated Hospital of the Army Medical University. Patients were randomly allocated to training and validation cohorts. Risk factors for gas-related complications were identified in the training cohort using univariate and multivariate analyses. We then constructed a nomogram and evaluated its predictive performance based on the area under the curve, decision curve analysis, and Hosmer-Lemeshow tests.

RESULTS

Gas-related complications developed in 39 of 353 patients who underwent transoral endoscopy at our institution. Diabetes, lesion origin, surgical resection method, and surgical duration were incorporated into the final nomogram. The predictive capability of the nomogram was excellent, with area under the curve values of 0.841 and 0.906 for the training and validation cohorts, respectively.

CONCLUSION

The ability of our four-variable nomogram to efficiently predict gas-related complications during transoral endoscopic resection enhanced postoperative assessments and surgical outcomes.

Preclinical Assessment of Tissue Effects by Gastrointestinal Endoscope Tip Temperature

Background

Endoscope tips are heated by their electrical and illuminating components. During the procedure, they might get in close or even direct contact with intestinal tissues.

Objective

To assess endoscope tip and tissue temperature as well as histopathologic changes of gastrointestinal (GI) tissues when exposed to the heated tip of GI endoscopes.

Methods

The endoscope tip temperatures of four GI endoscopes were measured for 30 minutes in a temperature-controlled chamber. The temperature of ex vivo porcine GI tissues was measured for 5-, 15-, and 120-minute exposure to endoscope tips within a climate chamber to control environmental factors (simulation of fever as worst-case). Exposed tissues were histopathologically examined afterward. Control samples included untreated mucosa, tissue samples exposed to endoscope tips for 120 minutes, as well as tissue samples thermally coagulated with a bipolar high-frequency probe.

Results

Actual endoscope tip temperatures of 59 to 86°C, dependent on the endoscope type, were measured. After 10 to 15 minutes, the maximum temperatures were reached. Maximum tissue temperatures of 44 to 46°C for 5 and 15 minutes, as well as up to 50°C for 120 minutes, were recorded dependent on tissue and endoscope type. No direct heat-induced histopathologic tissue alterations were observed in the 5- and 15-minute samples.

Conclusions

Both clinically relevant and a worst-case control were tested. Even though elevated temperatures were recorded, no heat-related tissue alterations were detected. This overall supports the safety profile of GI endoscopy; however, the study findings are limited by the ex vivo setting (no metabolic tissue alterations accessible, no blood flow) and small sample number.

Esophageal Dilation in Children: A State of the Art Review

Esophageal dilations in children are performed by several pediatric and adult professionals. We aim to summarize improvements in safety and new technology used for the treatment of complex and refractory strictures, including triamcinolone injection, endoscopic electro-incisional therapy, topical mitomycin-C application, stent placement, functional lumen imaging probe assisted dilation, and endoscopic vacuum-assisted closure in the pediatric population.

Clinical study of submucosal tunneling endoscopic resection and endoscopic submucosal dissection in the treatment of submucosal tumor originating from the muscularis propria layer of the esophagus

Herein, we aimed to evaluate the clinical value and safety of transendoscopic submucosal tunnel tumor resection (STER) and endoscopic submucosal dissection (ESD) for the resection of esophageal submucosal intrinsic muscle tumors. We retrospectively analyzed the clinical data of 68 patients with esophageal submucosal intrinsic muscle tumors treated with STER (STER group, n = 38, March 2018 to January 2020) or ESD (ESD group, n = 30, January 2017 to January 2020) at the First People's Hospital of Lianyungang to compare the treatment efficacy, hospitalization time and costs, and postoperative complications between the 2 groups. All 68 cases were of single lesions. The mean operative duration was shorter in the STER group (53.39 ± 11.57 min) than in the ESD group (68.33 ± 18.52 min, P < .05). The postoperative hospital stay duration was significantly shorter in the STER group (5.86 ± 1.01 days; P < .05) than in the ESD group (8.2 ± 3.4 days, P < .05). The mean hospitalization cost was significantly lower in the STER group than in the ESD group (12,468.8 + 4966.8 yuan vs 17,033.3 ± 4547.2 yuan; P < .05). Only 1 case of intraoperative perforation occurred in ESD group. There were no other complications in both groups. The wound healed in both groups, and no residual or recurrent tumors were detected during the follow-up period. Both STER and ESD can be used for the treatment of esophageal intrinsic muscular layer (MP) tumors, and STER is safer and more efficient for lesions with a diameter <3.5 cm.

Efficient Initial Eradication of Large Esophageal Varices by Balloon-compression Endoscopic Injection Sclerotherapy

BACKGROUND

The management of large esophageal varices (EVs) remains challenging because of the difficulty of endoscopic variceal ligation and fatal post-endoscopic variceal ligation bleeding ulcers. The current study evaluated the efficacy and safety of balloon-compression endoscopic injection sclerotherapy (bc-EIS) in the treatment of large EVs.

MATERIALS AND METHODS

This retrospective study included 105 patients with cirrhosis exhibiting large EVs (64 in the bc-EIS group and 41 in the EIS group). Primary outcomes included the initial rate of variceal eradication and intraoperative bleeding signs. Secondary outcomes included incidences of rebleeding, mortality, complications, and optimal time of balloon-compression (bc).

RESULTS

The initial rate of variceal eradication in the bc-EIS group was significantly higher than that in the EIS group (46.9 vs. 24.4%; P=0.021). The incidence of intraoperative bleeding, which was represented as oozing and spurting, in the bc-EIS group was markedly lower than that in the EIS group (43.8 vs. 61.0% and 9.4 vs. 39.0%, respectively; P=0.043). Patients in the bc-EIS group showed a significantly lower incidence of rebleeding (0.0 vs. 17.1%; P=0.001). However, no significant difference in mortality rate was observed between different groups. Chest pain or discomfort tended to be more common in the EIS group than in the bc-EIS group (58.5 vs. 17.2%; P=0.001). The cut-off value of 11.5-minutes appeared to have a maximum combined sensitivity and specificity of 80.0% and 58.8%, respectively. The area under the curve was 0.708 (95% confidence interval =0.576-0.839; P=0.004).

CONCLUSION

bc-EIS could achieve a higher variceal eradication rate and milder intraoperative bleeding signs in large EVs. Furthermore, 11.5-minutes appeared to be the optimal compression time in bc-EIS.

A prospective randomized controlled trial of the safety and efficacy of carbon dioxide insufflation compared with room air insufflation during gastric endoscopic submucosal dissection

BACKGROUND AND AIM

Carbon dioxide (CO₂ ) insufflation during gastric endoscopic submucosal dissection (GESD) under sedation can be used instead of room air insufflation. Appropriate monitoring of the partial pressure of CO₂ during GESD is necessary due to the impaired respiration. The aim of this study was to assess the safety and efficacy of CO₂ insufflation during GESD compared with conventional room air insufflation.

METHODS

Patients with a gastric epithelial neoplasm or early gastric cancer were enrolled. A total of 76 consecutive patients were randomly assigned to the CO₂ insufflation group (CO₂ group) or the room air insufflation group (air group). The primary outcome was the mean difference of end-tidal CO₂ (EtCO₂ ) between two groups.

RESULTS

The upper bound of the 95% CI for the mean EtCO₂ difference between the two groups before the procedure and at 15, 30 and 45 min after insufflation met the criteria for noninferiority. In a subgroup analysis of patients 70 years and older, the mean difference of EtCO₂ was not significantly different between two groups. However, the air group received more analgesics than the CO₂ group after the procedure (67.6% vs 35.1%, P = 0.005). In addition, in terms of improvement of abdominal pain or bowel gas after 24 h of GESD, CO₂ group showed better results than air group (both P < 0.05).

CONCLUSIONS

CO₂ insufflation during GESD is as safe as using room air, and patients, including elderly patients, receiving CO₂ achieve more rapid relief of abdominal pain and intra-abdominal residual gas during and after the procedure.

Transient End-Tidal Carbon Dioxide Elevation During Pediatric Upper Endoscopy With Carbon Dioxide Insufflation: Is It True Hypercapnia?

BACKGROUND

Endoscopic insufflation, long performed using air, is being replaced by carbon dioxide (CO2) at many pediatric centers, despite limited published data on its use in children. We have previously demonstrated that CO2 use during esophagogastroduodenoscopy (EGD) in non-intubated children is associated with transient elevations of end-tidal CO2 (EtCO2). This observation raised concerns about possible CO2 inhalation and systemic absorption. Here, we investigate this concern by concurrently measuring both EtCO2 and transcutaneous CO2 (tCO2) during upper endoscopic procedures in children.

AIM

To determine if elevations in EtCO2 levels seen in non-intubated children undergoing CO2 insufflation during EGD are associated with elevated systemic CO2 levels.

METHODS

Double-blinded, prospective, randomized clinical trial. Children were randomized 1:1 to receive either CO2 or air for endoscopic insufflation. EtCO2 was sampled with a CO2-sampling nasal cannula and tCO2 was monitored using the Radiometer transcutaneous monitoring device.

RESULTS

Fifty nine patients were enrolled; 30 patients in the CO2 insufflation group and 29 in the air group. All patients underwent a procedure involving an EGD. Transient elevations in EtCO2 (defined as >60 mmHg) were observed only in the CO2 insufflation group. This contrasted with the similar elevations of tCO2 between the CO2 and air insufflation groups. None of these events were of clinically significant magnitude or duration.

CONCLUSION

This study demonstrates that the observed transient elevations in EtCO2 seen during EGD in non-intubated children receiving CO2 insufflation are most likely measurements of eructated CO2 without evidence of excessive systemic absorption of CO2.

Relief Effect of Carbon Dioxide Insufflation in Transnasal Endoscopy for Health Checks-A Prospective, Double-Blind, Case-Control Trial

CO2 insufflation has proven effective in reducing patients’ pain after colonoscopies but has not been examined in esophagogastroduodenoscopies. Therefore, we examined the effect of CO2 insufflation in examinees who underwent transnasal endoscopies without sedation. This study is a single-center, prospective, double-blind, case-control trial conducted between March 2017 and August 2018. Subjects were assigned weekly to receive insufflation with either CO2 or air. The primary outcome was improvement of abdominal pain and distension at 2 h and 1-day postprocedure. In total, 336 and 338 examinees were assigned to the CO2 and air groups, respectively. Visual analog scale (VAS) scores for abdominal distension (15.4 vs. 25.5; p < 0.001) and distress from flatus (16.0 vs. 28.8; p < 0.001) at 2 h postprocedure were significantly reduced in the CO2 group. VAS scores for pain during the procedure (33.5 vs. 37.1; p = 0.059) and abdominal pain after the procedure (3.9 vs. 5.7; p = 0.052) also tended to be lower at 2 h postprocedure, but all parameters showed no significant difference at 1-day postprocedure. All procedures were safely completed through the planned program, and no apparent adverse events requiring treatment or follow-up occurred. In conclusion, CO2 insufflation may reduce postprocedural abdominal discomfort from transnasal esophagogastroduodenoscopies. (UMIN000028543).

Suspected cerebrovascular air embolism during endoscopic esophageal varices ligation under sedation with fatal outcome: A case report

BACKGROUND

Air embolism is a very rare, yet serious and potentially fatal complication of digestive endoscopic treatment. Air embolism is the result of air directly entering the arteries or veins. However, to recognize neurological dysfunction under sedation can be difficult. Therefore, it is extremely important to identify high-risk groups and take preventive measures.

CASE SUMMARY

Herein, we report a 74-year-old female patient with esophageal varices who suffered from consciousness disturbance after the third endoscopic ligation of esophageal varices under sedation. Combined with the patient’s imaging examination results and medical history, we highly suspected that the patient had developed paradoxical cerebral air embolism during endoscopic ligation. We learned that the patient died at a later follow-up. In order to be able to identify and prevent the occurrence of air embolism early, we summarize and analyze the risk factors, pathogenesis, clinical manifestations, prevention and treatment options of gastrointestinal endoscopy complicated by cerebral air embolism.

CONCLUSION

Electroencephalographic monitoring helps to recognize the occurrence of air embolism in time and increase the patient's chance of survival.

Low recurrence rate after endoscopic resection in non-ampullary duodenal lesions: A 16-year single-center retrospective study

Endoscopic resection (ER) for non-ampullary duodenal lesions (NADLs) is technically more difficult than lesions of the stomach. However, endoscopic treatment of duodenal lesions has been increasingly performed in recent years. This study aimed to evaluate the efficacy and safety of ER for NADLs.Patients who underwent ER for NADLs between 2004 and 2019 were retrospectively reviewed. Clinical and pathologic features of the lesions including the clinical outcomes and adverse events were analyzed.The study included 80 patients with NADLs. The mean age of patients was 59.3 years (22-80 years), the mean size of the lesion was 8.8 ± 7.0 mm, and the mean procedure time was 13.2 ± 11.2 min. Half (40/80) of the lesions were in the duodenal bulb including the superior duodenal angle. Final histological data showed 56 adenomas (70.5%), 13 Brunner gland tumors (16.2%), and 4 pyloric gland tumors (5.0%). The final diagnoses of 5 lesions after ER showed higher-grade dysplasia compared to pre-ER biopsy findings. The en bloc resection rate was 93.8% (75/80), and the complete resection rate with clear margins was 90.0% (72/80). Micro-perforation occurred in 2 of 80 patients and was successfully treated with conservative treatment. There were no cases of delayed bleeding. The mean follow-up period was 27.0 months (2-119 months) with no cases of recurrence.ER may be an effective treatment for NADLs with favorable long-term outcomes. However, the possibility of perforation complications should always be considered during ER.

When in Trouble Think of the Bubble: Paradoxical Cerebral Arterial Gas Embolism after Endoscopic Retrograde Cholangiopancreatography

Air embolism (a result of direct communication with the vasculature and an external pressure gradient from the gastrointestinal or the biliary tract), although rare, is a potentially devastating adverse event seen in endoscopic retrograde cholangiopancreatography (ERCP) procedures. Whether venous, arterial, or paradoxical, the clinical presentation ranges from asymptomatic patients to cardiorespiratory arrest. This is of particular importance because it makes the diagnosis of air embolism even more difficult in an already sedated patient. Since early recognition increases the chances of patients' survival, endoscopists should be highly motivated and trained to recognize this complication as early as possible. With only 60 cases of air embolism reported (and even fewer related to paradoxical air embolism), we aimed to report a case of paradoxical cerebral air embolism in a patient undergoing ERCP due to a common bile duct stricture and to provide a mini-review of this clinical entity that can serve as a bedside quick reference guide for endoscopists worldwide.

Insufflation of Carbon Dioxide versus Air During Colonoscopy Among Pediatric Patients: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background/Aims:

Carbon dioxide is increasingly used in insufflation during colonoscopy in adult patients; however, air insufflation remains the primary practice among pediatric gastroenterologists. This systematic review and meta-analysis aims to evaluate insufflation using CO₂ versus air in colonoscopies in pediatric patients.

Methods:

Individualized search strategies were performed using MEDLINE, Cochrane Library, EMBASE, and LILACS databases following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and Cochrane working methodology. Randomized control trials (RCTs) were selected for the present meta-analysis. Pooled proportions were calculated for outcomes including procedure time and abdominal pain immediately and 24 hours post-procedure.

Results:

The initial search yielded 644 records, of which five RCTs with a total of 358 patients (CO₂: n=178 versus air: n=180) were included in the final analysis. The procedure time was not different between the CO₂ and air insufflation groups (mean difference, 10.84; 95% confidence interval [CI], -2.55 to 24.22; p=0.11). Abdominal pain immediately post-procedure was significantly lower in the CO₂ group (risk difference [RD], -0.15; 95% CI; -0.26 to -0.03; p=0.01) while abdominal pain at 24 hours post-procedure was similar (RD, -0.05; 95% CI; -0.11 to 0.01; p=0.11).

Conclusions:

Based on this systematic review and meta-analysis of RCT data, CO₂ insufflation reduced abdominal pain immediately following the procedure, while pain was similar at 24 hours post-procedure. These results suggest that CO₂ is a preferred insufflation technique when performing colonoscopy in pediatric patients.

Safety of chronic obstructive pulmonary disease patients undergoing carbon dioxide insufflation in extended endoscopic procedures

Introduction:

Carbon dioxide (CO₂) insufflation for endoscopies has been shown to be more comfortable and safe, but only in patients without underlying chronic obstructive pulmonary disease (COPD). The aim of this study was to show that using CO₂ is safe in COPD patients.

Methods:

Patients were retrospectively identified who underwent extended endoscopic procedures during the time period of January 2012 to December 2017. Patients were included if they also had COPD. A matched control group without COPD was created during the same timeframe. All the patients were sedated with continuous monitoring of their CO₂ levels by end-tidal CO₂ (EtCO₂).

Results:

One hundred and ten patients had COPD and underwent an extended endoscopic procedure. These patients had a higher severity of their comorbidities (American Society of Anesthesiologists class 3 or 4) (93.6% [95% confidence interval [CI], 87.4%–96.9%] vs. 60.3% [95% CI, 51.1%–69.0%]; P < 0.01) and an increase of co-existing obstructive sleep apnea (33.6% vs. 6.3%, P < 0.01). There was no difference in baseline EtCO₂, but the peak EtCO₂ and postprocedure EtCO₂ were both significantly higher in the COPD group. The only postprocedural complication found was an inability to be extubated immediately following the procedure with subsequent need to hospitalize the patient, which occurred in three patients (2.8%; 95% CI, 0.9%–7.9%) in the COPD group and one (0.9%; 95% CI, 0.2%–4.9%) in the non-COPD group (P = 0.37).

Conclusion:

The present study, which was the only study looking at CO₂ insufflation specifically in COPD patients, provides evidence that CO₂ insufflation is safe in COPD despite a slight increase in EtCO₂.

Delayed perforation after endoscopic resection of a colonic laterally spreading tumor: A case report and literature review

BACKGROUND

Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) have been widely used for the treatment of early gastrointestinal cancer. Endoscopic piecemeal mucosal resection (EPMR) is derived from the combination of EMR and ESD. Delayed perforation with peritonitis after colonic EPMR is a rare but severe complication, sometimes requiring surgery. There are some associated risk factors, including patient- (location, diameter, and presence of fibrosis) and procedure-related factors. Early recognition and timely treatment are crucial for its management.

CASE SUMMARY

We report a case in which delayed perforation with peritonitis was treated using endoscopic closure. A 54-year-old man was diagnosed with a 30-mm-diameter laterally spreading tumor in the colonic hepatic curvature. Fifteen hours after endoscopic resection, peritonitis caused by delayed perforation occurred and gradually aggravated. Conservative treatment was ineffective and no obvious perforation was observed. After timely endoscopic closure, the patient was discharged on postoperative day 4.

CONCLUSION

In occasion of localized peritonitis aggravating without macroscopic perforation, endoscopic closure is an effective treatment for delayed perforation with stable vital signs in the early stage.

Is Carbon Dioxide Insufflation During Endoscopy in Children as Safe and as Effective as We Think?

OBJECTIVES

Distension of the gastrointestinal lumen is crucial for visualization and advancement during endoscopic procedures. An increasing number of pediatric centers now use carbon dioxide (CO2) preferentially over air as many adult studies and a few pediatric studies have concluded that CO2 is better tolerated than air, especially for colonoscopy.

AIMS

The aim of the study was to determine if CO2 is as safe and as effective as air and if it reduces abdominal discomfort and distension in children undergoing upper endoscopy and colonoscopy.

METHODS

Double blinded, prospective, randomized clinical study. Patient- and nursing-reported outcomes of pain and distension were recorded. End tidal CO2 (EtCO2) was monitored continuously with a CO2-sampling nasal cannula for patients undergoing procedural sedation and via the endotracheal tube for those who were intubated.

RESULTS

One hundred seventy-eight patients with 180 procedures were enrolled, 91 procedures were randomized to receive CO2, and 89 to air. Groups did not differ significantly with respect to nursing-assessed abdominal discomfort, change in girth from baseline, or endoscopist-perceived ease of inflation. Use of CO2 was associated with transient spikes in the EtCO2 (≥60 mmHg) in a significant number of patients during sedated upper endoscopy without endotracheal intubation. There was a reduction of bloating and flatulence for all procedures in the CO2 group.

CONCLUSIONS

The benefits of using CO2 for insufflation were minimal in our patients. The observed transient elevations of EtCO2 during sedated upper endoscopy raise concerns of possible systemic hypercarbia. The wisdom of its routine use for all pediatric endoscopic procedures is questioned.

Carbon dioxide gas endoscopy of the deep gluteal space

The treatment of hip and pelvic pain associated with abnormalities of the deep gluteal space has evolved and increasingly involves endoscopic techniques with a saline expansion medium. This investigation presents a surgical technique utilizing carbon dioxide as the insufflation medium for deep gluteal space endoscopy in 17 cadaveric hips. This technique was successful in 94% (16/17) of the hips, allowing for visualization of the sciatic nerve, posterior femoral cutaneous nerve, pudendal nerve, branch of the inferior gluteal artery crossing the sciatic nerve, piriformis muscle, hamstring tendon origin, and lesser trochanter. Our experience suggests that gas expansion presents several advantages over fluid expansion.

Efficacy and Safety of Carbon Dioxide Versus Air Insufflation for Colonoscopy in Deeply Sedated Pediatric Patients

OBJECTIVES

Studies have shown the advantages of carbon dioxide (CO2) over air insufflation in the adult population during colonoscopies. This study was designed to investigate the efficacy and safety of CO2 insufflation in deeply sedated children undergoing colonoscopy.

METHODS

This was a prospective, randomized, double-blind clinical trial. We recruited 100 consecutive pediatric patients who had colonoscopy under deep sedation for various indications. Patients were first randomized by history of abdominal pain and then randomly assigned to either CO2 or air insufflation. Postprocedural abdominal pain scores were registered on a 10-point visual analog rating scale and significant pain was defined as a score of 3 or higher. Abdominal circumferences and end tidal CO2 (ETCO2) levels were measured. Complications during and after the procedure were recorded.

RESULTS

We did not find statistically significant difference between CO2 and air insufflation on univariate analysis because of low number of children experiencing significant pain after colonoscopy. After adjusting for baseline pain, we found that pain was significantly lower in patients after CO2 versus air insufflation on multivariable analysis (P = 0.03). The significant factors related to pain were duration of the procedure (P = 0.006), history of abdominal pain (P = 0.002) and previous abdominal surgery (P = 0.02). CO2 insufflation was associated with decreased abdominal circumference after colonoscopy (P = 0.002). Girls were more likely to have pain regardless of intervention (P = .04).

CONCLUSIONS

Most children tolerate endoscopic procedures without significant pain. Our study was underpowered to show significant difference between air and CO2 on univariate analysis. CO2 insufflation during colonoscopy, however, may reduce postprocedural abdominal pain. Significant factors for increased pain on multivariate analysis included colonoscopy length over 30 minutes, history of abdominal pain, and previous abdominal surgery.

Sealing the hole: endoscopic management of acute gastrointestinal perforations

Acute perforations are one of the recognised complications of both diagnostic and therapeutic gastrointestinal (GI) endoscopy. The incidence rate varies according to the type of procedure and the anatomical location within the GI tract. For decades, surgical treatment has been the standard of care, but endoscopic closure has become a more popular approach, due to feasibility and the reduction of the burden of surgery. Various devices are available now such as through-the-scope clips, over-the-scope clips, endoscopic suturing devices, stents, bands and omental patch. All have been tested in studies done on humans or animal models, with a reasonable overall technical and clinical success rate, proving efficiency and feasibility of endoscopic closure. The choice of which device to use depends on the site and the size of the perforation. It also depends on availability of thee device and the endoscopist's experience. A number of factors that could predict success of endoscopic closure or favour surgical treatment have been suggested in different studies. After successful endoscopic closure, patients are usually kept nil by mouth and receive antibiotics for a duration that varied between different studies.

Transcutaneous partial pressure of carbon dioxide monitoring during EUS-guided drainage of peripancreatic fluid collections using carbon dioxide insufflation: A prospective study

Background:

Carbon dioxide (CO₂) insufflation has become more commonly used in EUS-guided interventions in recent years. However, there is a paucity of information regarding methods by which to monitor in vivo CO₂ levels. This study aimed to assess the feasibility of a novel noninvasive method to monitor transcutaneous partial pressure of CO₂ (P_CO2) (P_tcCO2) levels during EUS-guided drainage of peripancreatic fluid collections (PFCs). The safety of CO₂ insufflation in EUS-guided interventions was also investigated.

Patients and Methods:

Patients who underwent EUS-guided PFC drainage between September 2015 and December 2016 at Shengjing Hospital of China Medical University were prospectively enrolled in this study. P_tcCO2 was measured in all patients using a noninvasive sensor throughout the procedure.

Results:

There were 25 patients eligible to be included in this study. The mean procedure time was 53.1 min. The mean P_tcCO2 level was 40 ± 4 mmHg and 48 ± 5 mmHg before and after the procedure, respectively. The mean peak P_tcCO2 during the procedure was significantly higher at 53 ± 6 mmHg (P < 0.0001). No complications associated with CO₂ insufflation such as CO₂ narcosis, gas embolism, or arrhythmias were encountered.

Conclusions:

P_tcCO2 monitoring can accurately reflect the level of P_CO2 continuously and noninvasively. CO₂ insufflation is safe for patients undergoing relatively complicated EUS-guided drainage of PFCs.

Over-the-scope-clip applications for perforated peptic ulcer

AIM

To investigate the effectiveness of over-the-scope-clip (OTSC)-based endoscopic closure in patients with perforated peptic ulcer (PPU).

METHODS

One hundred six patients diagnosed with PPU were treated with either OTSC (n = 26) or conservative treatments (n = 80), respectively. The outcome assessments included technical success rate, clinical success rate, post-treatment complications after 1 month, mortality rate, time to resume oral feeding, length of hospital stay, and the administration of antibiotics.

RESULTS

In the OTSC group, technical and clinical success was achieved in 100% of patients without any complications, including death, incomplete closure, duodenal obstruction, and gastrointestinal bleeding, with a median operation time of 10 min. All patients in the OTSC group were discharged, while the mortality rate in the control group was 13.8%. Subsequent surgeries were required in 30% of patients in the control group. The median times to resume oral feeding were 3.5 (interquartile range [IQR] 2.0-5.25) days in the OTSC group and 7.0 (IQR 5.0-9.0) days in the control group (p < 0.001). One month post-procedure, 30% (24/80) of patients in the control group and 0 (0/26) in the OTSC group required additional operations (p < 0.001). No significant difference was found in the length of the hospital stay and the administration of antibiotics between the two groups (p > 0.05).

CONCLUSIONS

OTSC-based endoscopic technique, with a high clinical success rate and a shorter time to resume oral feeding, was effective in achieving closure of PPU with a diameter < 15 mm.

Carbon dioxide versus room air for colonoscopy in deeply sedated pediatric patients: a randomized controlled trial

Background and study aims  Use of carbon dioxide (CO ₂ ) instead of room air (RA) during colonoscopy in adults revealed significantly less flatulence and abdominal pain in several studies. The objectives of this study were to investigate the effects of CO ₂ usage on post-interventional pain, abdominal discomfort, abdominal girth, pCO ₂ levels, and narcotic requirement in deeply sedated pediatric patients. Patients and methods  A total of 97 children and adolescents aged 4 years to 17 years undergoing colonoscopy were randomized to RA or CO ₂ in a prospective, randomized, controlled trial. Age-appropriate pain scales assessed abdominal pain as primary outcome. In addition, abdominal girth, abdominal bloating, transcutaneous pCO ₂ , narcotic requirement to achieve deeply sedation, and post-procedural analgesic demand was analyzed in 73 patients. Results  Overall, significantly fewer patients reported bloating in the CO ₂ group ( P  = 0.0012). However, we observed only a trend to lower post-interventional pain ( P  = 0.15) and a lower pain score. There was no significant difference in transcutaneous pCO ₂ level and no adverse events occurred. Although there was no difference in the dosage of propofol and midazolam, we observed a significant increased necessity for use of synthetic opioids in the RA group to achieve optimal examination conditions ( P  = 0.023). Conclusions  The benefits using CO ₂ in colonoscopy of deeply sedated children predominate. In particular, CO ₂ insufflation may allow a less painful post-interventional time and it significantly reduces abdominal bloating. Moreover, with CO ₂ , significantly less additional opioids were used. Thus, CO ₂ insufflation can be considered as safe in deeply sedated patients as there was no relevant pulmonary CO ₂ retention observed. (DRKS00013914).

Carbon dioxide versus air insufflation enteroscopy: a systematic review and meta-analysis based on randomized controlled trials

OBJECTIVES

 To compare the insufflation of CO ₂ and ambient air in enteroscopy.

SEARCH SOURCES

 The investigators researched the electronic databases MedLine, Cochrane Library, Central, LILACS, BVS, Scopus and Cinahl. The grey search was conducted in the base of theses of the University of São Paulo, books of digestive endoscopy and references of selected articles and in previous systematic revisions.

STUDY ELIGIBILITY CRITERIA

 The evaluation of eligibility was performed independently, in a non-blind manner, by two reviewers, firstly by title and abstract, followed by complete text. Disagreements between the reviewers were resolved by consensus.

DATA COLLECTION AND ANALYSIS METHOD

 Through the spreadsheet of data extraction, where one author extracted the data and a second author checked the extraction. Disagreements were resolved by debate between the two reviewers. The quality analysis of the studies was performed using the Jadad score. The software RevMan 5 version 5.3 was used for the meta-analysis.

RESULTS

 Four randomized clinical trials were identified, totaling 473 patients submitted to enteroscopy and comparing insufflation of CO ₂ and ambient air. There was no statistical difference in the intubation depth between the two groups. When CO ₂ insufflation was reduced, there was a significant difference in pain levels 1 hour after the procedure (95 % IC, -2.49 [-4.72, -0.26], P : 0.03, I ² : 20%) and 3 hours after the procedure (95% IC, -3.05 [-5.92, -0.18], P : 0.04, I ² : 0 %). There was a usage of lower propofol dosage in the CO ₂ insufflation group, with significant difference (95 % IC, -67.68 [-115.53, -19.84], P : 0.006, I ² : 0 %). There was no significant difference between the groups in relation to the use of pethidine and to the oxygen saturation.

LIMITATIONS

 Restricted number of randomized clinical trials and nonuniformity of data were limitations to the analysis of the outcomes.

CONCLUSION

 The use of CO ₂ as insufflation gas in enteroscopy reduces the pain levels 1 hour and 3 hours after the procedure, in addition to the reduction of the sedation (propofol) dosage used.

Cerebral air embolism following an endoscopic variceal ligation: A case report

BACKGROUND

Cerebral air embolism (CAE) is a rare but potentially devastating complication of endoscopic procedures. Only 3 cases, to our knowledge, have been reported.

CASE PRESENTATION

A 50-year-old female patient presented with hepatitis C virus-related hepatic cirrhosis, emergency endoscopy and endoscopic variceal ligation was performed in an awakened state. CAE occurred during procedure, the patient passed away the next day in the intensive care unit.

CONCLUSIONS

CAE is a rare but potentially devastating complication in endoscopic procedures. We need more preventive tools and treatments.

UK guidelines on oesophageal dilatation in clinical practice

These are updated guidelines which supersede the original version published in 2004. This work has been endorsed by the Clinical Services and Standards Committee of the British Society of Gastroenterology (BSG) under the auspices of the oesophageal section of the BSG. The original guidelines have undergone extensive revision by the 16 members of the Guideline Development Group with representation from individuals across all relevant disciplines, including the Heartburn Cancer UK charity, a nursing representative and a patient representative. The methodological rigour and transparency of the guideline development processes were appraised using the revised Appraisal of Guidelines for Research and Evaluation (AGREE II) tool.Dilatation of the oesophagus is a relatively high-risk intervention, and is required by an increasing range of disease states. Moreover, there is scarcity of evidence in the literature to guide clinicians on how to safely perform this procedure. These guidelines deal specifically with the dilatation procedure using balloon or bougie devices as a primary treatment strategy for non-malignant narrowing of the oesophagus. The use of stents is outside the remit of this paper; however, for cases of dilatation failure, alternative techniques-including stents-will be listed. The guideline is divided into the following subheadings: (1) patient preparation; (2) the dilatation procedure; (3) aftercare and (4) disease-specific considerations. A systematic literature search was performed. The Grading of Recommendations Assessment, Develop-ment and Evaluation (GRADE) tool was used to evaluate the quality of evidence and decide on the strength of recommendations made.

Carbon dioxide insufflation during endoscopic resection of large colorectal polyps can reduce post-procedure abdominal pain: A prospective, double-blind, randomized controlled trial

Background

Studies of the use of CO₂ insufflation during endoscopic resection of large colorectal polyps (LCPs) are lacking.

Objective

We evaluated the effect of CO₂ insufflation on pain after endoscopic resection of LCPs.

Methods

In a prospective randomized controlled trial (RCT), 132 patients were randomly assigned to groups who underwent endoscopic resection with CO₂ insufflation (CO₂ group, n = 66) or air insufflation (air group, n = 66). The primary outcome was abdominal pain post-procedure (PP). The secondary outcomes were abdominal distension, rates of technical success, amounts of sedatives prescribed, use of analgesics, and adverse events.

Results

Baseline patient characteristics were similar between the groups. The mean abdominal pain score was 12.3 in the CO₂ group vs. 17.5 in the air group at 1 h PP (p  =  0.047). Also, the proportion of patients without pain was significantly higher in the CO₂ group at 1 h PP (p = 0.008). The pain score differed more in the endoscopic submucosal dissection group and long-time group. The secondary outcomes were not significantly different between the two groups.

Conclusions

The results of this RCT demonstrate the superiority of CO₂ insufflation for endoscopic resection of LCPs in terms of decreasing PP abdominal pain (KCT0001636).

Endoscopic mucosal resection of non-ampullary sporadic duodenal adenomas: a retrospective analysis with long-term follow-up

OBJECTIVE

We investigate the efficiency of endoscopic mucosal resection (EMR) of non-ampullary sporadic duodenal adenomas (NASDA) in a retrospective analysis with long-term follow-up.

METHODS

Consecutive patients undergoing EMR of NASDA between May 2002 and December 2016 were retrospectively identified from an electronic database. Endoscopic follow-up was scheduled after 3, 6 and 12 months for the first year, then yearly for up to five years.

RESULTS

EMR of 75 NASDA was performed in 68 patients (56% en-bloc, 44% piecemeal). Retroperitoneal perforations occurred in 3/68 (4.4%) patients, were treated by surgical (n = 2) or percutaneous (n = 1) drainage; delayed bleeding was reported in 13/75 (17.3%) resections and was successfully managed by endoscopy (n = 12) or radiologic embolization (n = 1). There was no procedure-related mortality. Follow-up was available in 61/68 patients (89.7%) after a median time of 59 months from resection. Residual and recurrent adenoma were diagnosed in 9 (14.5%) and 6 (10.9%) cases, respectively; all but one were successfully retreated endoscopically.

CONCLUSIONS

EMR for NASDA is effective with a favorable long-term outcome. Local recurrences can be retreated endoscopically. A recall system, patient's compliance to endoscopic follow-up are mandatory to detect recurrences and their prompt treatment.

Management of Inflammatory Fluid Collections and Walled-Off Pancreatic Necrosis

OPINION STATEMENT

Pancreatic fluid collections are a frequent complication of acute pancreatitis. The revised Atlanta criterion classifies chronic fluid collections into pseudocysts and walled-off pancreatic necrosis (WON). Symptomatic PFCs require drainage options that include surgical, percutaneous, or endoscopic approaches. With the advent of newer and more advanced endoscopic tools and expertise, minimally invasive endoscopic drainage has now become the preferred approach. An endoscopic ultrasonography (EUS)-guided approach for pancreatic fluid collection drainage is now the preferred endoscopic approach. Both plastic stents and metal stents are efficacious and safe; however, metal stents may offer an advantage, especially in infected pseudocysts and in WON. Direct endoscopic necrosectomy is often required in WON. Lumen apposing metal stents allow for direct endoscopic necrosectomy and debridement through the stent lumen and are now preferred in these patients. Endoscopic retrograde cholangiopancreatography with pancreatic duct exploration should be performed concurrent to PFC drainage in patients with suspected PD disruption. PD disruption is associated with an increased severity of pancreatitis, an increased risk of recurrent attacks of pancreatitis and long-term complications, and a decreased rate of PFC resolution after drainage. Ideally, pancreatic ductal disruption should be bridged with endoscopic stenting.

Carbon dioxide insufflation is associated with increased serrated polyp detection rate when compared to room air insufflation during screening colonoscopy

BACKGROUND AND STUDY AIMS

Sessile serrated adenomas (SSA) and traditional serrated adenomas (TSA) have been increasingly recognized as precursors of colorectal cancer. The aim of this study was to compare the effect of carbon dioxide insufflation (CO ₂ I) vs. room air insufflation (AI) on serrated polyp detection rate (SPDR) and to identify factors associated with SPDR.

PATIENTS AND METHODS

Single-center retrospective cohort study of 2083 screening colonoscopies performed with AI (November 2011 through January 2013) or CO ₂ I (February 2013 to June 2015). Data on demographics, procedure characteristics and histology results were obtained from a prospectively maintained endoscopy database and chart review. SPDR was defined as proportion of colonoscopies in which ≥ 1 SSA, TSA or hyperplastic polyp (HP) ≥ 10 mm in the right colon was detected. Multi-variate analysis (MVA) was performed to identify predictors of SPDR.

RESULTS

A total of 131 histologically confirmed serrated polyps (129 SSA, 2 TSA and 0 HP ≥ 10 mm) were detected. SPDR was higher with CO ₂ I vs. AI (4.8 % vs. 1.4 %; P  < 0.0001). On MVA, CO ₂ I was associated with higher SPDR when compared to AI (OR: 9.52; 95 % CI: 3.05 - 30.3). Both higher body mass index (OR 1.05; 95 % CI:1.02 - 1.09) and longer colonoscope withdrawal time (OR 1.11; 95 % CI: 1.07 - 1.16) were also associated with higher SPDR.

CONCLUSION

CO ₂ I is associated with higher SPDR when compared to AI during screening colonoscopy. While the mechanism remains unknown, we speculate that the favorable gas characteristics of CO ₂ compared to room air results in improved polyp detection by optimizing bowel insufflation. These findings suggest an additional reason to prefer the use of CO ₂ I over AI during colonoscopy.

Colorectal endoscopic mucosal resection (EMR)

Colonoscopy has the benefit of detecting and treating precancerous adenomatous polyps and thus reduces mortality associated with CRC. Screening colonoscopy is the keystone for prevention of colorectal cancer. Over the last 20 years there has been increased in the management of large colorectal polyps from surgery to endoscopic removal techniques which is less invasive. Traditionally surgical resection was the treatment of choice for many years for larger polyps but colectomy poses significant morbidity of 14-46% and mortality of up to 7%. There are several advantages of endoscopic resection technique over surgery; it is less invasive, less expensive, has rapid recovery, and preserves the normal gut functions. In addition patient satisfaction and efficacy of EMR is higher with minor complications. Thus, this has facilitated the development of advanced resection technique for the treatment of large colorectal polyps called as endoscopic mucosal resection (EMR).

Comparison of carbon dioxide and air insufflation during consecutive EGD and colonoscopy in moderate-sedation patients: a prospective, double-blind, randomized controlled trial

BACKGROUND AND AIMS

Endoscopy is performed with air insufflation and is usually associated with abdominal pain. It is well recognized that carbon dioxide (CO₂) is absorbed more quickly into the body than air; however, to date, few studies have investigated the use of CO₂ insufflation during consecutive EGD and colonoscopy (CEC). Thus, this study evaluated the efficacy of CO₂ insufflation compared with air insufflation in CEC.

METHODS

From March 2014 to April 2016, a total of 215 consecutive patients were randomly assigned to receive CO₂ insufflation (CO₂ group, n = 108) or air insufflation (air group, n = 107). Abdominal pain after CEC was recorded on a visual analogue scale (VAS). The amount of sedatives administered, use of analgesics, polyp detection rate (PDR), adenoma detection rate (ADR), abdominal circumference, and adverse events were also analyzed.

RESULTS

Baseline patient characteristics were not significantly different between the groups. Abdominal pain on the VAS in the CO₂ group and air group 1 hour after CEC was, respectively, 13.8 and 20.1 (P = .010), 3 hours after CEC was 8.3 and 12.5 (P = .056), 6 hours after CEC was 3.5 and 5.3 (P = .246), and 1 day after CEC was 1.8 and 3.4 (P = .192). The dose of sedative administered, analgesic usage, PDR, ADR, and adverse events were not statistically different between the groups. However, the increase in abdominal circumference was significantly higher in the air group than in the CO₂ group.

CONCLUSIONS

CO₂ insufflation was superior to air insufflation with regard to the pain score on the VAS in the hour after CEC. (Clinical trial registration number: KCT0001491.).

Carbon Dioxide versus Air Insufflation in Gastric Endoscopic Submucosal Dissection: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background/Aims

Endoscopic submucosal dissection (ESD) with air insufflation is commonly used for the staging and treatment of early gastric carcinoma. However, carbon dioxide (CO₂) use has been shown to cause less post-procedural pain and fewer adverse events. The objective of this study was to compare the post-procedural pain and adverse events associated with CO₂ and air insufflation in ESD.

Methods

A systematic search was conducted for randomized control trials (RCTs) comparing the two approaches in ESD. The Mantel-Haenszel method was used to analyze the data. The mean difference (MD) and odds ratio (OR) were used for continuous and categorical variables, respectively.

Results

Four RCTs with a total of 391 patients who underwent ESD were included in our meta-analysis. The difference in maximal post-procedural pain between the two groups was statistically significant (MD, -7.41; 95% confidence interval [CI], -13.6 – -1.21; p=0.020). However, no significant differences were found in the length of procedure, end-tidal CO₂, rate of perforation, and postprocedural hemorrhage between the two groups. The incidence of overall adverse events was significantly lower in the CO₂ group (OR, 0.51; CI, 0.32–0.84; p=0.007).

Conclusions:

CO₂ insufflation in gastric ESD is associated with less post-operative pain and discomfort, and a lower risk of overall adverse events compared with air insufflation.

Efficacy and safety of carbon dioxide insufflation versus air insufflation for endoscopic retrograde cholangiopancreatography: A meta-analysis update

BACKGROUND AND OBJECTIVE

Endoscopic retrograde cholangiopancreatography (ERCP) is essential for visualising the biliary tree and pancreatic ducts, and carbon dioxide (CO₂) insufflation during ERCP is considered an alternative technique to air insufflation for relieving post-procedural abdominal discomfort (abdominal pain and distension). The aim of the present study was to evaluate the effect of CO₂ insufflation on the remission of abdominal discomfort and the potential side effects by conducting a meta-analysis.

METHODS

The method recommended by the Cochrane Collaboration was employed to conduct a meta-analysis of randomised controlled trials (RCTs) of CO₂ insufflation versus air insufflation during ERCP. The PubMed, EMBASE, Cochrane Library, ISI Web of Science and China Biology Medicine disc (CBMdisc) databases were comprehensively searched.

RESULTS

Nine high-quality RCTs were reviewed. The updated meta-analysis showed that the CO₂ groups achieved a lower abdominal pain score [1-hour (SMD: -1.44, 95% CI: -2.76, -0.15), 3-hour (SMD: -1.17, 95% CI: -2.18, -0.16) and 6-hour (SMD: -1.39, 95% CI: -2.68, -0.10)], a lower abdominal distension score [1-hour (SMD: -1.05, 95% CI: -1.73, -0.38), 3-hour (SMD: -0.63, 95% CI: -1.10, -0.16) and 6-hour (SMD: -0.54, 95% CI: -0.99, -0.08)] and a lower overall rate of complications (OR: 0.59; 95% CI: 0.37, 0.93). There was no significant difference between the groups regarding abdominal discomfort immediately after recovery or 24-hour post-procedure. There was no evidence to indicate higher pressure of CO₂ (pCO₂) values in the CO₂ groups during the procedure when the patients were under sedation anaesthesia.

CONCLUSIONS

Compared to air insufflation, CO₂ insufflation is currently the preferred method for ERCP and decreases post-procedural abdominal pain and distension without significant side effects.

Carbon dioxide insufflation during colonoscopy in inflammatory bowel disease patients: a double-blind, randomized, single-center trial

OBJECTIVE

Bowel distension by insufflated air causes abdominal discomfort after colonoscopy. Carbon dioxide (CO2) instead of air insufflation during colonoscopy can reduce postprocedural discomfort in diagnostic and screening cases. Discomfort after colonoscopy and CO2 insufflation have never been studied in inflammatory bowel disease (IBD) patients, characterized by younger age, structural changes of the colon, and need for repeated and frequently uncomfortable colonoscopies. Our trial was designed to evaluate postprocedural discomfort associated with CO2 compared with air insufflation in unsedated or minimally sedated patients with known IBD.

METHODS

In a double-blind, randomized, single-center study, 64 patients were randomized to either CO2 insufflation (CO2) or air insufflation colonoscopy (Air). Abdominal pain, bloating, and flatulence scores during 24 h after colonoscopy were recorded using a continuous scale of 0-10 (0=none, 10=maximum discomfort). The primary endpoint used for power calculation was bloating score at 1 h after colonoscopy.

RESULTS

Pain, bloating, and flatulence scores at end, 1, and 3 h after colonoscopy were significantly lower in CO2 than in Air arm (P<0.001). Scores at 6, 12, and 24 h were comparable. Procedural parameters such as cecal and terminal ileum intubation rate, intubation and total time, pain during insertion, need for repositioning, and abdominal compression were not different between arms. No complications were recorded in the study.

CONCLUSION

Compared with air, CO2 insufflation significantly reduces abdominal pain, bloating, and flatulence scores during at least 3 h after colonoscopy in IBD patients, achieving comparable intraprocedural outcomes.

Exploring the Small Bowel: Update on Deep Enteroscopy

Deep enteroscopy allows for the diagnosis and treatment of small bowel disorders that historically required operative intervention. There are a variety of endoscopic platforms using balloons and rotational overtubes to facilitate small bowel intubation and even allow for total enteroscopy. Obscure gastrointestinal bleeding is the most common indication for deep enteroscopy. By visualizing segments of the small bowel not possible through standard EGD or push enteroscopy, deep enteroscopy has an established high rate of identification and treatment of bleeding sources. In addition to obscure bleeding, other common indications include diagnosis and staging of Crohn's disease, evaluation of findings on capsule endoscopy and investigation of possible small bowel tumors. Large endoscopy databases have shown deep enteroscopy to be not only effective but safe. Recent research has focused on comparing the diagnostic rates, efficacy, and total enteroscopy rates of the different endoscopic platforms.

Flexible Gastro-intestinal Endoscopy - Clinical Challenges and Technical Achievements

Flexible gastro-intestinal (GI) endoscopy is an integral diagnostic and therapeutic tool in clinical gastroenterology. High quality standards for safety, patients' comfort, and efficiency have already been achieved. Clinical challenges and technical approaches are discussed in this short review.

Image enhanced endoscopy for further characterization of mucosal and vascular patterns includes dye-spray or virtual chromoendoscopy. For confocal laser endoscopy, endocytoscopy, and autofluorescence clinical value has not yet been finally evaluated. An extended viewing field provided by additional cameras in new endoscopes can augment detection of polyps behind folds. Attachable caps, flaps, or balloons can be used to flatten colonic folds for better visualization and stable position.

Variable stiffness endoscopes, radiation-free visualization of endoscope position, and different overtube devices help reducing painful loop formation in clinical routine. Computer assisted and super flexible self-propelled colonoscopes for painless sedation-free endoscopy need further research. Single-use devices might minimize the risk of infection transmission in the future.

Various exchangeable accessories are available for resection, dissection, tunneling, hemostasis, treatment of stenosis and closure of defects, including dedicated suturing devices. Multiple arm flexible devices controlled via robotic platforms for complex intraluminal and transmural endoscopic procedures require further improvement.

Painless Colonoscopy: Available Techniques and Instruments

During colonoscopy, air insufflation to distend the lumen and facilitate careful inspection and scope insertion can induce pain and cause discomfort. Carbon dioxide (CO₂) insufflation can decrease abdominal pain and discomfort during and after colonoscopy. The advantage of CO₂ insufflation is the rapid absorption of the gas across the intestine. Another painless option is water-assisted colonoscopy. Two methods for water-assisted colonoscopy are available: water immersion and water exchange. In a recent direct comparison, the water exchange method was superior to water immersion, CO₂ insufflation, and air insufflation with respect to pain during colonoscopy, although it still had the disadvantage of being a time-consuming procedure. Cap-assisted colonoscopy is a simple technique involving the use of a small transparent cap attached to the tip of the scope. Three studies showed an advantage of this technique in terms of reduced patient discomfort compared with the conventional method. Three robotic colonoscopy systems (Endotics System [Era Endoscopy], NeoGuide [NeoGuide Systems Inc.], and Invendoscope [Invendo Medical]) have been introduced to evaluate pain reduction during colonoscopy, but none has been widely adopted and used in practice. In this review, clinical trials of several techniques and new devices for painless colonoscopy are described and summarized.

Carbon dioxide insufflation in esophageal endoscopic submucosal dissection reduces mediastinal emphysema: A randomized, double-blind, controlled trial

AIM

To assess the efficacy of CO₂ insufflation for reduction of mediastinal emphysema (ME) immediately after endoscopic submucosal dissection (ESD).

METHODS

A total of 46 patients who were to undergo esophageal ESD were randomly assigned to receive either CO₂ insufflation (CO₂ group, n = 24) or air insufflation (Air group, n = 22). Computed tomography (CT) was carried out immediately after ESD and the next morning. Pain and abdominal distention were chronologically recorded using a 100-mm visual analogue scale (VAS). The volume of residual gas in the digestive tract was measured using CT imaging.

RESULTS

The incidence of ME immediately after ESD in the CO₂ group was significantly lower than that in the Air group (17% vs 55%, P = 0.012). The incidence of ME the next morning was 8.3% vs 32% respectively (P = 0.066). There were no differences in pain scores or distention scores at any post-procedure time points. The volume of residual gas in the digestive tract immediately after ESD was significantly smaller in the CO₂ group than that in the Air group (808 mL vs 1173 mL, P = 0.013).

CONCLUSION

CO₂ insufflation during esophageal ESD significantly reduced postprocedural ME. CO₂ insufflation also reduced the volume of residual gas in the digestive tract immediately after ESD, but not the VAS scores of pain and distention.

Preprocedural Assessment for Sedation in Gastrointestinal Endoscopy

The role of the anesthesia service in sedation for gastrointestinal endoscopy (GIE) has been steadily increasing. The goals of preprocedural assessment are determined by the specific details of the procedure, the issues related to the illness that requires the endoscopy, comorbidities, the goals for sedation, and the risk of complications from the sedation and the endoscopic procedure. Rather than consider these issues as separate entities, they should be considered as part of a continuum of preparation for GIE. This is told from the perspective of an anesthesiologist who regularly participates in the full range of sedation for GIE.

Colonoscopy Comfort: An Evidence-Based Practice Project

Decreased discomfort after colonoscopy is a high priority for patients. Typically, air is used to insufflate the bowel during colonoscopy, but emerging literature shows that carbon dioxide insufflation decreases postoperative discomfort and flatus. An evidence-based practice project was developed and implemented by a surgical department at a community hospital. The Director of Surgical Services brought the evidence to the staff, secured agreement from a physician champion, and the new process was quickly adopted. Patients experienced less discomfort and flatus postprocedure with carbon dioxide insufflation, and were able to be discharged expediently. These patient outcomes validated the literature and confirmed the success of the practice change.

Carbon dioxide insufflation during colonoscopy can significantly decrease post-interventional abdominal discomfort in deeply sedated patients: A prospective, randomized, double-blinded, controlled trial

BACKGROUND AND AIM

CO2 has been reported to be absorbed from the bowel more rapidly than air, resulting in a discomfort reduction after colonoscopy. Its role in deeply sedated patients is limited. This study was designed to investigate the efficacy and safety of CO2 insufflation during colonoscopy in patients deeply sedated with propofol.

METHODS

A total of 125 continuous patients were randomly assigned to receive either CO2 (n = 63) or air (n = 62) insufflation during propofol-sedated colonoscopy. Postcolonoscopy abdominal pain, distention, and satisfaction were assessed at 1, 3, and 24 h after the procedure, and the proportions of pain-free and distention-free patients were compared. Residual bowel gas in the colon and small bowel was evaluated at 1 h after colonoscopy. End-tidal CO2 and O2 saturation was measured for safety analysis.

RESULTS

There was a significant difference between the two groups regarding the postcolonoscopy abdominal pain, distention, and subjective satisfaction at 1 h (P < 0.001) and 3 h (P < 0.01) after the procedure. Patients' pain and distention at 1 and 3 h after the procedure were significantly lower in the CO2 group (P < 0.01). Residual bowel gas in the colon and small bowel was significantly less in the CO2 group (P < 0.001). There was no significant difference in end-tidal CO2 levels between two groups before, during, and after the procedure.

CONCLUSIONS

Compared with air, CO2 insufflation during colonoscopy reduced postcolonoscopy abdominal discomfort and improved patients' satisfaction. It was safe to use CO2 insufflation in deeply sedated colonoscopy.

Insufflation with carbon dioxide reduces pneumoperitoneum after percutaneous endoscopic gastrostomy (PEG): a randomized controlled trial

BACKGROUND AND STUDY AIMS

Pneumoperitoneum following PEG placement has been reported in up to 60 % of cases, and while usually benign and self-limited, it can lead to evaluation for suspected perforation. This study was designed to determine whether using CO2 compared to ambient air for insufflation during PEG reduces post-procedure pneumoperitoneum.

PATIENTS AND METHODS

Prospective, double-blind, randomized trial of 35 consecutive patients undergoing PEG at a single academic medical center. Patients were randomized to insufflation with CO2 or ambient air. The primary outcome was pneumoperitoneum determined by left-lateral decubitus abdominal x-rays 30 minutes after PEG placement. Secondary endpoints included abdominal distention, pain, and bloating.

RESULTS

PEG was successfully placed in 17 patients using CO2 and 18 patients using ambient air. Three patients in each arm were unable or declined to have x-rays completed and were excluded. Pneumoperitoneum was identified in 2/14 (14.3 %) using CO2 and 8/15 (53.3 %) using ambient air (P = 0.05). There was no significant difference in abdominal distention, visual analog scale (VAS) scores for pain or bloating between CO2 and ambient air.

CONCLUSION

Utilizing CO2 significantly reduces the frequency of post-procedural pneumoperitoneum compared to use of ambient air during PEG placement, with no difference in waist circumference, pain or bloating between CO2 and ambient air. CO2 appears to be safe and effective for use and may be the insufflation agent of choice during PEG.

The Endoscopic Treatment of Iatrogenic Gastrointestinal Perforation

BACKGROUND

Iatrogenic gastrointestinal perforation is a life-threatening complication that arises very rarely in routine endoscopic procedures, with an incidence of 0.03-0.8%. It is more likely in highly complex and invasive therapeutic interventions. In certain situations, endoscopic closure of the perforation and treatment with antibiotics can obviate the need for emergency surgical repair.

METHODS

This review is based on pertinent articles retrieved by a selective literature search in PubMed and on a relevant position paper.

RESULTS

Existing clinical studies of treatment for iatrogenic gastrointestinal perforation are mainly retrospective and uncontrolled. No randomized and controlled trials have been performed to date. If the perforation is discovered soon after it arises, endoscopic treatment can be considered. Gastrointestinal perforations that are less than 30 mm in size can be closed with a clip. In the esophagus, expanding metal stents can be used as well. Clip application is successful in 80-100% of cases of gastrointestinal perforation, and the perforation remains permanently closed in 60-100% of cases. Reports on the endoscopic treatment of esophageal perforation show mixed results, with closure rates of roughly 90% and clinical success rates of roughly 80%. If endoscopic treatment is not possible, timely laparoscopic or open surgical repair is needed.

CONCLUSION

The endoscopic treatment of iatrogenic perforations is safe and reliable. Success depends on early detection, adequate endoscopic closure with properly mastered technique, and the early initiation of concomitant antibiotic treatment, which must be continued for a full course. Most patients who are treated in this way do not need emergency surgery.

Autologous collagen induced chondrogenesis (ACIC: Shetty-Kim technique) - A matrix based acellular single stage arthroscopic cartilage repair technique

The defects of articular cartilage in the knee joint are a common degenerative disease and currently there are several established techniques to treat this problem, each with their own advantages and shortcomings. Autologous chondrocyte implantation is the current gold standard but the technique is expensive, time-consuming and most versions require two stage procedures and an arthrotomy. Autologous collagen induced chondrogenesis (ACIC) is a single-stage arthroscopic procedure and we developed. This method uses microfracture technique with atelocollagen mixed with fibrin gel to treat articular cartilage defects. We introduce this ACIC techniques and its scientific background.

Evaluation of abdominal circumference and salivary amylase activities after unsedated colonoscopy using carbon dioxide and air insufflations

OBJECTIVE

To assess and compare abdominal distention and stress in unsedated colonoscopy using carbon dioxide (CO2 ) and air insufflations.

METHODS

Two hundred and five patients underwent colonoscopic examinations without sedation using either CO2 or air insufflation. Abdominal circumference and salivary amylase (sAMY) activities before and 0 and 15 min after colonoscopy were measured by a nurse who was blinded to the grouping of the patients.

RESULTS

In all, 102 and 103 patients were randomly recruited in the CO2 and air insufflation groups, respectively. sAMY activities before and 0 and 15 min after colonoscopy were not significantly different between the two groups. Abdominal circumference measured immediately and 15 min after colonoscopy was significantly smaller in CO2 insufflation group than in the air insufflation group (81.2 cm vs 84.0 cm, and 79.7 cm vs 83.6 cm, respectively; P <0.05). The increasing ratio of abdominal circumference immediately after colonoscopy was not significantly different between the two groups; however, the ratio at 15 min after colonoscopy using CO2 insufflation was significantly lower than that in the air insufflation group (1.007 vs 1.028, P <0.001).

CONCLUSION

sAMY activities after unsedated colonoscopy using CO2 insufflation were not improved; however, CO2 insufflation decreases abdominal circumference after colonoscopy compared with air insufflation.

Efficacy of carbon dioxide insufflation during gastric endoscopic submucosal dissection: a randomized, double-blind, controlled, prospective study

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) is commonly performed under air insufflation and is often accompanied by abdominal discomfort. CO2 is absorbed more rapidly by the body than is air; however, the use of CO2 insufflation in ESD remains controversial. This randomized, double-blind, controlled, prospective study was designed to assess the efficacy of CO2 versus air insufflation in gastric ESD.

METHODS

Between May 2012 and August 2014, a total of 110 patients with gastric tumors were randomly assigned to the CO2 insufflation (CO2 group, n = 54) or air insufflation group (air group, n = 56). Abdominal pain after ESD was chronologically recorded via visual analog scale (VAS) scores. Secondary outcome measurements were adverse events, abdominal circumference, amount of sedatives prescribed, and use of analgesics.

RESULTS

Neither the baseline patient characteristics nor the mean procedural time differed between the groups. The VAS score for abdominal pain was 35.2 in the CO2 insufflation group versus 48.5 in the air insufflation group 1 hour after ESD (P = .026), 27.8 versus 42.5 three hours after ESD (P = .007), 18.4 versus 34.8 six hours after ESD (P = .001), and 9.2 versus 21.9 one day after ESD (P < .001). Changes in abdominal circumference, the amounts of sedative drugs taken, and the adverse events did not differ between the groups. However, the air insufflation group required more analgesics than did the CO2 insufflation group (CO2 group, 22.0% [11/50]; air group, 42.3% [22/52]; P = .028).

CONCLUSIONS

CO2 insufflation during gastric ESD significantly reduced abdominal pain and analgesic usage compared with air insufflation. (

CLINICAL TRIAL REGISTRATION NUMBER

NCT01579071.)