CO2 Insufflation Research Articles

Improved Safety of Endoscopic Vessel Harvesting During the COVID-19 Pandemic

The COVID-19 pandemic has necessitated that operating room procedures be modified to ensure the safety of staff and patients. Specifically, procedures that have the potential to create aerosolization must be reassessed, given the risk of viral transmission via aerosolization. We present the use of a nonsealed endoscopic vessel harvesting approach during coronary surgery that does not necessitate the use of CO2 insufflation and utilizes suction through an ultra low particulate filter, thus mitigating the risk of possible viral transmission via aerosolization or surgical smoke production. This approach is technically feasible and can minimize the risk of viral transmission during endoscopic vessel harvesting.

Tu1085 POST-OPERATIVE CROHN'S DISEASE PATIENTS UNDERGOING COLONOSCOPY REQUIRE SIGNIFICANTLY MORE ANALGESIA & SEDATION COMPARED TO A NON-IBD POST-OPERATIVE POPULATION

Rates of surgical intervention in Crohn’s disease have declined. However, a significant proportion of patients still require surgical resection and have been shown to have higher post-op pain scores and analgesia requirements. The aim of this study was to assess sedation requirements and comfort scores of post-operative Crohn’s disease patients at endoscopy. Patients with a previous intestinal resection undergoing colonoscopy 2014-2017 were identified via an electronic reporting system. Data regarding patient & disease characteristics, sedation requirements, Gloucester comfort scores and endoscopy reports were collected.Crohn’s disease patients with prior intestinal resection were compared to a non-IBD population post-intestinal resection. 212 patients were included. n=66 Crohn’s disease, n=2 UC and n=144 non-IBD patients underwent colonoscopy. Patient characteristics described in Table 1. 10.8% of patients had a documented history of chronic pain, hysterectomy or other relevant conditions that may affect comfort scores. 53% of patients with Crohn’s disease were on active treatment for IBD at the time of endoscopy. The median dose of midazolam administered was 3mg (IQR 2.12-4mg); median fentanyl dose was 50mcg. (IQR 50-75mcg).Significantly more midazolam was used in 2014 compared to procedures performed in 2016-17. (median 4mg vs 3mg; p=0.014). The median dose of Midazolam given was significantly higher in patients with Crohn’s disease (3mg IQR 3-5mg vs 3mg IQR 2-4; p=0.009).The median dose of fentanyl required was significantly higher in post-operative Crohn’s disease patients. (75mcg IQR 50-100mcg vs 50mcg ; p=0.001). The median comfort score in the Crohn’s disease patients was higher (indicating more discomfort) when compared to the non-IBD cohort. (median score 2 & 1 respectively) There was no significant difference in the proportion of patients with chronic pain etc or with multiple intestinal resections. (p=0.5 and p=0.41). There was a statistically significant difference in comfort scores with only n=25 Crohn’s disease patients (37.9%) having comfort score 1 when compared to n=79 non-IBD patients (55%) (p=0.04). Post-op Crohn’s disease patients with significant active endoscopic disease required significantly higher doses of midazolam compared to those patients with quiescent disease.(4mg IQR 3-5mg vs 3mg IQR 2.5-4mg;p=0.038) There was a trend towards significance in fentanyl dose. (75mcg IQR 50-100mcg vs 50mcg IQR 50-100mcg;p=0.06) Patients with Crohn’s disease undergoing colonoscopy in the post-operative setting have significantly higher analgesia requirements. Comfort scores are significantly worse when compared to non-IBD patients who have had similar intestinal resections. Endoscopists should use techniques e.g. CO2 insufflation, in addition to medication to ensure comfort amongst patients with Crohn’s disease.

Mo1695 WATER EXCHANGE (WE) INCREASES SESSILE SERRATED POLYP DETECTION RATE (SSPDR) COMPARED WITH AIR (AI) OR CARBON DIOXIDE (CO2) INSUFFLATION - POOLED DATA ANALYSIS OF FOUR RECENT REPORTS

A net-work meta-analysis (GIE. 2018;88:589) showed water exchange (WE) provided the highest adenoma detection rate (ADR). The impact on sessile serrated polyp detection rate (SSPDR) was not addressed. SSP have increased malignant potential (Curr Treat Options Gastroenterol. 2015;13:156). They have subtle appearance (AJG. 2012;107:1315). They cluster in the proximal colon (61%) (Arch Pathol Lab Med. 2015;139:388) co-localizing with interval cancers (64% to 68%) (Gastro. 2014;146:950; Cancer. 2012;118:3044). The finding of SSPs was mentioned in several RCTs comparing WE with air (AI) or carbon dioxide (CO2) insufflation. We test the hypothesis that compared with air (AI) or carbon dioxide (CO2) insufflation, water exchange (WE) could enhance the real-time detection of SSP. The aim is to assess the impact of WE (vs. AI or CO2) on SSPDR. Four reports with data on SSP and WE vs. AI or CO2 insufflation were identified. Demographic, procedural and SSP data were extracted, pooled and analyzed. By pooling the data in four RCTs the pitfall of type II error due to small sample size could be avoided. Table 1 summarizes the salient demographic and procedural features. Table 2 shows that the pooled SSPDR of WE (8.0%) was significantly higher than that of air or CO2 insufflation combined (5.0%) (p=0.0017, Fisher exact test). The combined data showed WE significantly increased SSPDR by 3%. With an estimated 19 million colonoscopies in the US in 2018 (https://idataresearch.com/an-astounding-19-million-colonoscopies-are-performed-annually-in-the-united-states/), 3.0% of 19 million (570,000) is clinically meaningful. The improved outcomes of increased SSPDR add value to WE colonoscopy. The improved value appears to justify consideration to incorporate WE into colorectal cancer prevention programs.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

Hyperamylasemia Post Living Donor Nephrectomy Does Not Relate to Pain.

IntroductionThe aetiology of pain after laparoscopic donor nephrectomy remains unclear. Given the proximity of the left kidney to the tail of the pancreas, we aimed to assess whether mobilisation and retrieval of the left kidney might inflame the pancreas, leading to pain and hyperamylasaemia in the post-operative period.Patient and methodsIn the present study, 16 consecutive live kidney donors were analysed in the same three months period. Amylase levels were measured on days 1 and 2. For each 24-hour period post-operatively analgesia consumption was recorded, as well as pain scores at rest on a visual analogue scale (VAS).ResultsThree out of 16 donors presented hyperamylasemia. A multiple regression analysis found levobupivacaine dose, propofol dose, transversus abdominis plane block and day 1 amylase did not significantly predict pain scores. Interestingly, body mass index significantly correlated with increased pain scores (p = 0.041). Also, increasing CO2 insufflation pressure and use of local anaesthetic infusion catheters predicted a decreased deep pain score (p = 0.036 and p = 0.037).ConclusionThere was no correlation of amylase levels and pain scores. Pancreatitis is a rare complication of nephrectomy and no overt cases were seen in the case of donor nephrectomy.

End-expiratory lung volume assessment using helium and carbon dioxide in an experimental model of pediatric capnoperitoneum.

Capnoperitoneum during laparoscopy leads to cranial shift of the diaphragm, loss in lung volume, and risk of impaired gas exchange. Infants are susceptible to these changes and bedside assessment of lung volume during laparoscopy might assist with optimizing the ventilation. Thus, the primary aim was to investigate the monitoring value of a continuous end-expiratory lung volume (EELV) assessment method based on CO2 dynamics ( ) in a pediatric capnoperitoneum model by evaluating the correlation and trending ability against helium washout (EELVHe ). Intra-abdominal pressure (IAP) was randomly varied between 0, 6, and 12mmHg with CO2 insufflation, while positive end-expiratory pressure (PEEP) levels of 3, 6, and 9cm H2 O were randomly applied in eight anesthetized and mechanically ventilated chinchilla rabbits. Concomitant and EELVHe and lung clearance index (LCI) were obtained under each experimental condition. Significant correlations were found between and EELVHe before capnoperitoneum (r=.85, P<.001), although increased IAP distorted this relationship. The negative influence of IAP was counteracted by the application of PEEP 9, which restored the correlation between and EELVHe and resulted in 100% concordance rate between the methods regarding changes in lung volume. EELVHe and LCI showed a curvilinear relationship, and an EELVHe of approximately 20mLkg-1 , determined with a receiver operating characteristic curve, was associated with near-normal LCI values. In this animal model of pediatric capnoperitoneum, reliable assessment of changes in EELV based on requires an open lung strategy, defined as EELV above approximately 20mLkg-1 .

Pneumoperitoneum in Veterinary Laparoscopy: A Review.

Objective: To review the effects of carbon dioxide pneumoperitoneum during laparoscopy, evaluate alternative techniques to establishing a working space and compare this to current recommendations in veterinary surgery. Study Design: Literature review. Sample Population: 92 peer-reviewed articles. Methods: An electronic database search identified human and veterinary literature on the effects of pneumoperitoneum (carbon dioxide insufflation for laparoscopy) and alternatives with a focus on adaptation to the veterinary field. Results: Laparoscopy is the preferred surgical approach for many human and several veterinary procedures due to the lower morbidity associated with minimally invasive surgery, compared to laparotomy. The establishment of a pneumoperitoneum with a gas most commonly facilitates a working space. Carbon dioxide is the preferred gas for insufflation as it is inert, inexpensive, noncombustible, colorless, excreted by the lungs and highly soluble in water. Detrimental side effects such as acidosis, hypercapnia, reduction in cardiac output, decreased pulmonary compliance, hypothermia and post-operative pain have been associated with a pneumoperitoneum established with CO2 insufflation. As such alternatives have been suggested such as helium, nitrous oxide, warmed and humidified carbon dioxide and gasless laparoscopy. None of these alternatives have found a consistent benefit over standard carbon dioxide insufflation. Conclusions: The physiologic alterations seen with CO2 insufflation at the current recommended intra-abdominal pressures are mild and of transient duration. Clinical Significance: The current recommendations in veterinary laparoscopy for a pneumoperitoneum using carbon dioxide appear to be safe and effective.

The influence of esophagogastroduodenoscopy using carbon dioxide insufflation on abdominal ultrasonographic imaging efficiency.

The ability to perform abdominal ultrasonography after esophagogastroduodenoscopy (EGD) is hypothesized to improve examination efficiency. Therefore, we performed abdominal ultrasonography before and after EGD to verify the effects of EGD on abdominal ultrasonographic imaging efficiency. We performed abdominal ultrasonography before, immediately after, 30min after, and 60min after EGD with carbon dioxide (CO2) insufflation in 23 consecutive patients who visited our center between July 2015 and December 2016. We examined the visualization status of the head, body, and tail of the pancreas; extrahepatic bile duct; and inferior pole of the right kidney. The visualization status of the pancreas decreased immediately after EGD in approximately 50% of patients; however, at 30min and after, the status was almost the same as for imaging performed before endoscopy. Visualization of the extrahepatic bile duct decreased slightly immediately after the procedure; however, 30min and later, it was almost the same as before endoscopy. The inferior pole of the right kidney was observable from the dorsal side and could be visualized at all examination points in all patients. There was no difficulty in performing abdominal ultrasonography at 30min or later following EGD with CO2 insufflation. Additionally, visualization of the head, body, and tail of the pancreas as well as the extrahepatic bile duct was improved in some patients.

Comparison of Detection Methods for Tracheoesophageal Fistulae With a Novel Method: Capnography With CO2 Insufflation.

Tracheoesophageal fistulae (TEF) are difficult to detect and require a high index of suspicion. We hypothesized that capnography to identify a spike in end-tidal carbon dioxide (etCO2) during esophagoscopy with carbon dioxide (CO2) insufflation would facilitate TEF diagnosis because of gas passage from the esophagus to the trachea. Medical records of 42 consecutive cases of recurrent, acquired, or missed congenital TEF diagnosed between January 2015 and November 2019 that underwent esophagoscopy with CO2 insufflation were reviewed. A control cohort of 97 similarly endoscopically evaluated patients with surgical confirmation of absence of recurrent TEF (eg, patients undergoing posterior tracheopexy) was also collected. All patients underwent pre-operative esophagoscopy, bronchoscopy, and capnography; diagnostic abilities of various combinations of modalities for TEF identification were calculated. Statistical analysis identified a maximum intra-esophagoscopy end-tidal CO2 level of 68 mmHg as the optimal discriminator between cases and controls, though in practice, we anecdotally find that recurrent TEFs typically permit rapid rise ≥90 mmHg. Increasing numbers of diagnostic modalities increased diagnostic sensitivity to detect recurrent TEF; the highest diagnostic sensitivity for TEF identification was achieved by the combination of intra-esophagoscopy fluoroscopy with bronchoscopy and capnography ≥68 mmHg (sensitivity = 88.1%). There were multiple cases of TEF (N = 7 for etCO2 ≥68 mmHg, N = 3 for etCO2 ≥90 mmHg) identified by capnography that were missed by esophagoscopy. There were 5 (for etCO2 ≥68 mmHg) or 6 (for etCO2 ≥90 mmHg) cases of recurrent TEF that were missed by all nonsurgical methods. Attention to etCO2 during esophagoscopy with CO2 insufflation represents a simple, novel way to detect TEF. Identification of TEF remains challenging, though combinations of diagnostic modalities improve diagnostic sensitivity.

Adult cardiac surgery and the COVID-19 pandemic: Aggressive infection mitigation strategies are necessary in the operating room and surgical recovery

The COVID-19 pandemic necessitates aggressive infection mitigation strategies to reduce the risk to patients and healthcare providers. This document is intended to provide a framework for the adult cardiac surgeon to consider in this rapidly changing environment. Preoperative, intraoperative, and postoperative detailed protective measures are outlined. These are guidance recommendations during a pandemic surge to be used for all patients while local COVID-19 disease burden remains elevated.

Effect of Different Levels of Positive End-Expiratory Pressure (PEEP) on Respiratory Status during Gynecologic Laparoscopy.

BackgroundDuring gynecologic laparoscopy, pneumoperitoneum, and the position of the patient's head can lead to pathophysiologic changes in cardiovascular and respiratory systems, complicating the management of anesthesia in these patients. One of the strategies for improving the respiratory status of patients undergoing laparoscopy is the use of Positive End-Expiratory Pressure (PEEP).ObjectivesThis study aimed to evaluate the effect of different levels of PEEP on the respiratory status of patients undergoing gynecologic laparoscopy.MethodsIn this clinical trial, 60 patients with ASA I were randomly assigned to three groups to control anesthesia: ZEEP (PEEP 0 cmH2O; 20 cases), PEEP5 (PEEP 5 cmH2O; 20 cases), and PEEP10 (PEEP 10 cmH2O; 20 cases). Respiratory and hemodynamic variables of patients were compared before general anesthetic induction and immediately after CO2 insufflation at intervals of 5, 10, 20, 30, and 60 min and the end of the operation in the three study groups.ResultsThe PEEP application improved pH, PaCO2, and PaO2 levels at the end of pneumoperitoneum compared to baseline when compared with the non-use of PEEP (ZEEP group). Also, the frequency of dysrhythmia in the use of PEEP in controlled ventilation was significantly lower in patients with PEEP10 (P < 0.05). The application of PEEP5 resulted in similar effects to PEEP10 in the levels of respiratory variables.ConclusionsThe PEEP application is associated with improved arterial blood gas in patients with gynecologic laparoscopy. The use of PEEP10 has a greater effect on the improvement of respiratory parameters and complications of pneumoperitoneum.

MP04-06 THE IMPACT OF PNEUMOPERITONEUM ON RENAL FUNCTION AND THE DEVELOPMENT OF ACUTE KIDNEY INJURY

INTRODUCTION AND OBJECTIVE: Minimally invasive surgery is considered the gold standard approach for many urologic surgical procedures. However, it requires CO2 insufflation that causes elevated intra-abdominal pressure (IAP) and may result in adverse pulmonary, cardiovascular, gastrointestinal and renal changes. One of the main risk factors for developing post-operative acute kidney injury (AKI) is diabetes mellitus (DM). DM is considered an epidemic disease with rising incidence; hence the aim of this study was to examine whether the effect of pneumoperitoneum on renal function and the development of AKI is more pronounced in diabetic rats compared with normal rats. METHODS: Sprague Dawley rats were divided into two groups: Control (non-diabetic) rats (n=7) and diabetic rats (n=10). A Veress needle was used for CO2 inflation allowing the intra-abdominal pressure to be increased to desired levels of: 7, 10 and 14 mmHg for the duration of 45 minutes each. At the end, CO2 was deflated allowing pressure to decrease to 0 mmHg for 60 minutes (recovery phase). During each pressure point hemodynamic parameters were recorded and urine samples were collected for analysis of NGAL (neutrophil gelatinase associated lipocalin) a novel AKI biomarker. RESULTS: As shown in the Table, there were no statistically significant changes from baseline in urinary flow, urinary sodium excretion (UNaV), GFR, and RPF during 7 mmHg pressure in both groups. When the intra-abdominal pressure was further elevated, a significant deterioration of these parameters was recorded. This trend was more pronounced among the diabetic rats. When examining urinary NGAL, a linear correlation was observed between the intra-abdominal pressure and the biomarker level. This correlation was more significant in the diabetic group. CONCLUSIONS: The present study demonstrated a direct correlation between intra-abdominal pressure elevation and the development of AKI. Diabetic rats were more sensitive to the deleterious effect of pneumoperitoneum and urinary NGAL levels may be used as a future biomarker to predict post-operative AKI especially in diabetic patients.Source of Funding: None

Effects of pneumoperitoneum with carbon dioxide on renal and hepatic functions in rats.

IntroductionLaparoscopic surgery is a preferred method based on its many benefits. However, increasing abdominal pressure by CO2 insufflation during the implementation of this technique poses challenges.AimTo determine the degree of renal and liver injury that occurs in a pneumoperitoneum (PP) model of prolonged CO2 insufflation.Material and methodsTwenty-one female Sprague Dawley rats were separated randomly into three groups. Group 1 was the control group and given anesthesia for 3 h. In group 2, PP was administered under anesthesia for 1 h. In the last group, PP was administered under anesthesia to animals for 3 h. We measured renal and liver injury biomarkers and made a histopathological evaluation to estimate the degree of injury and assessed the correlation of biomarkers including kidney injury molecule-1 (KIM-1) with histopathological findings.ResultsHistopathological analysis according to the kidney ischemia tubular damage score showed a statistically significant difference between the 3 groups (p < 0.001). There was an increase in KIM-1 levels in the groups, although it was not statistically significant (p = 0.062, p = 0.156, p = 0.350 respectively). According to the correlation test in this research, KIM-1 results had a statistically significant association with creatinine, urea, aspartate aminotransferase and alanine aminotransferase levels in all control and study groups.ConclusionsAccording to our results, the increase in KIM-1 was correlated with Cr levels and compatible with histopathological analysis. Moreover, intra-abdominal pressure statistically significantly increased the degree of kidney injury and there was not a significant increase in the levels of KIM-1. There was no difference in liver damage between groups.

Protective effects of postconditioning in transvaginally created pneumoperitoneum.

There are reports of ischemic complications in clinical practice after laparoscopy using pneumoperitoneum. Conditioning has a beneficial effect for various ischemic diseases. This experimental study was designed to evaluate the effects of postconditioning in transvaginally created pneumoperitoneum. Sixty adult female rats, weighing 300±50 g were divided into four equal groups. Pneumoperitoneum was created by CO2 insufflation under a pressure of 10 mmHg. Rats in the first group (sham) were subjected to only sham-operation or gas insufflation. The second group (TV/PP) was subjected to pneumoperitoneum for 60 min followed by 30 min of desufflation. The third group (post-5) was subjected to pneumoperitoneum for 60 min followed by 5 min of desufflation, 5 min of insufflation and again followed by 30 min of desufflation. The fourth group (post-2.5) was subjected to pneumoperitoneum for 60 min followed by 2.5 min of desufflation and 2.5 min of insufflation-repeated in two cycles- and then followed by 30 min of desufflation. The rats were sacrificed, and blood was collected after 30 min, 2 and 6 h from the last desufflation. Levels of oxidative stress markers, malondialdehyde (MDA), superoxide dismutase (SOD), reduced glutathione (GSH), sulfhydryl groups (SH) and inflammatory cytokine TNF-α, were analyzed. Levels of MDA in the post-5 group were significantly reduced compared to the TV/PP and post-2.5 groups. The level of GSH in TV/PP animals was markedly reduced compared to the Sham, Post-5 and Post-2.5 groups. In addition, levels of SH were increased in the Post-5 group in comparison to the Sham, TV/PP and Post-2.5 groups. No difference in the activity of SOD between the groups was found, and the concentration of TNF-α in TV/PP animals was significantly higher than that in the Sham and postconditioning groups. Overall, the results of the present study indicate that postconditioning can reduce pneumoperitoneum-induced oxidative injury.

Evaluation of a ventral and a left lateral approach to coelioscopy in bearded dragons (Pogona vitticeps).

To compare a ventral and a left lateral endoscopic approach to coelioscopy in bearded dragons (Pogona vitticeps). 18 adult bearded dragons. In a randomized crossover design involving 2 surgical approaches, anesthetized bearded dragons first underwent coelioscopy with a ventral approach (left lateral of midline next to the umbilicus; animal positioned in dorsal recumbency) or left lateral approach (intercostal; animal positioned in right lateral recumbency) and then with the alternate approach. A 2.7-mm × 18-cm, 30° oblique telescope with a 4.8-mm operating sheath and CO2 insufflation at 2 to 5 mm Hg were used. Ease of entry into the coelom and ease of visual examination of visceral structures were scored. Both approaches were straightforward, with the left lateral approach requiring significantly more time than the ventral approach. Scores for ease of visual examination for the heart, lungs, liver, stomach, intestines, pancreas, gallbladder, left kidney, gonads, and fat body were good to excellent. Visual examination of the spleen and adrenal glands was difficult in most animals via either approach. The left kidney, testis, and vas deferens were easier to see with the left lateral approach, whereas the pancreas in females and gallbladder in both sexes were easier to see with the ventral approach. All bearded dragons recovered without complications from the procedures, except for one with nephritis, renal gout, and hepatic necrosis. Both coelioscopy approaches could be safely and effectively used in bearded dragons. Choice of approach should be based on the coelomic structures requiring evaluation.

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

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. 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. 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). 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.

P618 Post-operative Crohn’s disease patients undergoing colonoscopy require significantly more analgesia and sedation compared with a non-IBD population

Abstract Background Rates of surgical intervention in Crohn’s disease have declined. However, a significant proportion of patients still require surgical resection and have been shown to have higher post-op pain scores and analgesia requirements. The aim of this study was to assess sedation requirements and comfort scores of post-operative Crohn’s disease patients at endoscopy. Methods Patients with a previous intestinal resection undergoing colonoscopy in 2017 were identified using an electronic reporting system. Data regarding patient demographics, disease characteristics, sedation requirements, comfort scores and endoscopy reports were collected. Patients with Crohn’s disease were compared with a non-IBD post-op population. Results n = 153 patients were included. n = 56 Crohn’s disease, n = 2 UC and n = 95 non-IBD patients underwent colonoscopy. Patient characteristics in Table 1. 13.6% of patients had a documented history of chronic pain or other relevant conditions that may affect comfort scores. 68.3% of patients with Crohn’s disease were on therapy at the time of endoscopy. The median dose of midazolam administered was 3 mg (IQR 2–4 mg); median fentanyl dose was 50 μg. (IQR 50–75 μg). The median dose of Midazolam was significantly higher in patients with Crohn’s disease (3 mg IQR 3–4 mg vs. 3 mg IQR 2–3; p = 0.006). The median dose of fentanyl required was also significantly higher in post-operative Crohn’s patients (50 μg IQR 50–100 μg vs. 50 μg; p = 0.001). The median comfort score in Crohn’s disease patients was higher (indicating more discomfort) when compared with the non-IBD cohort. (median score 2 and 1 respectively) There was no significant difference in the proportion of patients with chronic pain or multiple intestinal resections (p = 0.84 and p = 0.142). There was a statistically significant difference in comfort scores;n = 19 Crohn’s disease patients (39.6%) had comfort score 1, compared with n = 70 non-IBD patients (71.4%) (p = 0.04). There was no significant difference in the median doses of midazolam or fentanyl when comparing Crohn’s disease patients with and without active endoscopic disease. (p = 0.07 and p = 0.10 respectively). Conclusion Patients with Crohn’s disease undergoing colonoscopy in the post-operative setting have significantly higher analgesia requirements. Comfort scores are significantly worse when compared with non-IBD patients who have had similar intestinal resections. Endoscopists should use techniques, e.g. CO2 insufflation in addition to medication to ensure comfort amongst patients with Crohn’s disease.

Efficacy and safety of water-exchange enteroscopy compared to carbon dioxide insufflation during enteroscopy.

carbon dioxide (CO2) insufflation during enteroscopy reduces procedure time and subsequent symptoms and increases the insertion depth compared with room air. In colonoscopy, the water-exchange (WE) technique is associated with less pain compared with CO2 insufflation. The WE technique is not well studied in enteroscopy. The aim of this study was to compare the efficacy and safety of enteroscopy with WE and CO2. a prospective, comparative and observational study was performed of double balloon enteroscopies (DBE) that were randomized in two groups. The first group used WE while the second group used CO2 insufflation. The data collected was evaluated via univariate analysis and multiple logistic regression (variables with p ≤ 0.10 according to the univariate analysis). forty-six DBE were included; 23 in each arm. The median age of cases was 63.5 years and 37% were female. There were no statistical differences between the groups with regard to the access route, findings, therapy and complications. Four patients (20%) in the CO2 group had adverse events (abdominal distension and pain) and one in the WE group (nausea), which was not statistically significant. The median insertion depth was greater in the CO2 group; 260 cm vs 160 cm (p = 0.048). Multiple logistic regression showed a statistically significant difference in the insertion depth using CO2 insufflation (OR 1.009, 1.001-1.017; p = 0.034). DBE with a CO2 insufflation technique and WE are safe with a greater insertion depth with CO2.

Effects of intra-abdominal pressure on laparoscopic working space in domestic rabbits (Oryctolagus cuniculus).

To assess the effects of 3 intra-abdominal pressures (IAPs) on pneumoperitoneal (laparoscopic working space) volume in domestic rabbits (Oryctolagus cuniculus). 6 female New Zealand White rabbits. A Latin-square design was used to randomly allocate sequences of 3 IAPs (4, 8, and 12 mm Hg) to each rabbit in a crossover study. Rabbits were anesthetized, subumbilical cannulae were placed, and CT scans were performed to obtain baseline measurements. Each IAP was achieved with CO2 insufflation and maintained for ≥ 15 minutes; CT scans were performed with rabbits in dorsal, left lateral oblique, and right lateral oblique recumbency. The abdomen was desufflated for 5 minutes between treatments (the 3 IAPs). Pneumoperitoneal volumes were calculated from CT measurements with 3-D medical imaging software. Mixed linear regression models evaluated effects of IAP, rabbit position, and treatment order on working space volume. Mean working space volume at an IAP of 8 mm Hg was significantly greater (a 19% increase) than that at 4 mm Hg, and was significantly greater (a 6.9% increase) at 12 mm Hg than that at 8 mm Hg. Treatment order, but not rabbit position, also had a significant effect on working space. Minor adverse effects reported in other species were observed in some rabbits. A nonlinear increase in abdominal working space was observed with increasing IAP. Depending on the type of procedure and visual access requirements, IAPs > 8 mm Hg may not provide a clinically important benefit for laparoscopy in rabbits.

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.

Relationship between Gastric pH Measurement and Intra-abdominal Pressure in Patients Undergoing Laparoscopic Surgery.

Objectives:Laparoscopic surgery (LS) is a safe and widely used technique. During LS, carbon dioxide insufflation may produce significant hemodynamic and ventilatory consequences, such as elevated intra-abdominal pressure (IAP) and hypercarbia. Splanchnic and cardiovascular blood flow can be affected by the elevated IAP, which can result in ischemia in the splanchnic region prior to hemodynamic changes. Changes in gastric pH may be an early precursor of changes in splanchnic blood circulation. This study investigated the relationship between gastric pH measurement and IAP in patients undergoing LS.Methods:This study included 49 patients aged 18–65 years with American Society of Anesthesiologists (ASA) physical status I – III who were undergoing elective laparoscopic cholecystectomy. A gastric pH tonometer probe was applied using an orogastric catheter. Simultaneously, insufflation pressure, cardiac apex beat (CAB), and mean arterial blood pressure (MAP) values were recorded. Indirect IAP was then measured through the bladder. Measurements were performed at baseline; at 15, 30, and 60 minutes after onset of insufflation (AI 15, AI 30, and AI 60, respectively); and at the end of insufflation (EI). Two pH measurements were obtained with a gastric tonometer pH probe, using an automated function of the gastric tonometer to improve measurement reliability.Results:IAP was significantly higher than baseline at AI 15, AI 30, AI 60, and EI (p<0.001). The pH1 and pH2 levels were significantly lower at AI 15 and AI 30, compared with baseline (p<0.001). There were no significant differences between pH1 and pH2 measurements at AI 60 and EI. Compared with baseline, CAB was significantly lower at AI 15, AI 30, AI 60, and EI (p=0.001, p<0.001, p=0.006). There were no statistically significant differences in MAP changes at any time point.Conclusion:Elevated IAP caused by CO2 insufflation during LS led to reductions of pH1 and pH2. There was a correlation between gastric pH measurement and IAP. Measurement of gastric pH may be useful to assess blood circulation in the splenic area during LS.