CO2 Pneumoperitoneum Pressure Research Articles

Application of different CO2 pneumoperitoneum pressure in laparoscopic pyeloplasty for infants with ureteropelvic junction obstruction.

Laparoscopic pyeloplasty is a minimally invasive approach for the therapy of infant ureteropelvic junction obstruction (UPJO), reliant on CO2 pneumoperitoneum insufflation. While the impact of CO2 insufflation on adult and older pediatric populations has been studied, its effects on infants remain less explored. This prospective randomized controlled trial included infants with UPJO undergoing laparoscopic pyeloplasty. Patients were allocated to low pneumoperitoneum pressure (LPP, 5 mmHg) or high pneumoperitoneum pressure (HPP, 8 mmHg) groups. Surgical parameters, postoperative complications, acid-base balance, stress markers, inflammatory cytokines, and oxidative stress markers were evaluated and compared. A total of 116 infants were analyzed. Preoperative characteristics were comparable between LPP and HPP groups. No significant differences in blood loss, operation time, or hospitalization time were observed. Postoperative complications were similar between groups. Acid-base balance analysis revealed a decrease in pH after pneumoperitoneum in both groups, with greater reductions in actual base excess and standard base excess in the HPP group. Stress markers, cytokines, and oxidative stress markers increased postoperatively in both groups, with higher levels in the HPP group. HPP leads to more pronounced physiological responses, including acid-base alterations, stress reactions, and inflammatory cytokine elevations.

Impact of Standard Versus Low Pneumoperitoneum Pressure on Peritoneal Environment in Laparoscopic Cholecystectomy. Randomized Clinical Trial.

High CO 2 pneumoperitoneum pressure during laparoscopy adversely affects the peritoneal environment. This study hypothesized that low pneumoperitoneum pressure may be linked to less peritoneal damage and possibly to better clinical outcomes. One hundred patients undergoing scheduled laparoscopic cholecystectomy were randomized 1:1 to low or to standard pneumoperitoneum pressure. Peritoneal biopsies were performed at baseline time and 1 hour after peritoneum insufflation in all patients. The primary outcome was peritoneal remodeling biomarkers and apoptotic index. Secondary outcomes included biomarker differences at the studied times and some clinical variables such as length of hospital stay, and quality and safety issues related to the procedure. Peritoneal IL6 after 1 hour of surgery was significantly higher in the standard than in the low-pressure group (4.26±1.34 vs. 3.24±1.21; P =0.001). On the contrary, levels of connective tissue growth factor and plasminogen activator inhibitor-I were higher in the low-pressure group (0.89±0.61 vs. 0.61±0.84; P =0.025, and 0.74±0.89 vs. 0.24±1.15; P =0.028, respectively). Regarding apoptotic index, similar levels were found in both groups and were 44.0±10.9 and 42.5±17.8 in low and standard pressure groups, respectively. None of the secondary outcomes showed differences between the 2 groups. Peritoneal inflammation after laparoscopic cholecystectomy is higher when surgery is performed under standard pressure. Adhesion formation seems to be less in this group. The majority of patients undergoing surgery under low pressure were operated under optimal workspace conditions, regardless of the surgeon's expertise.

Effects of sevoflurane and propofol on the optic nerve sheath diameter in patients undergoing laparoscopic gynecological surgery: a randomized controlled clinical studies

BackgroundThe results of studies on changes in intracranial pressure in patients undergoing laparoscopic surgery are inconsistent. Meanwhile, previous neurosurgery studies have suggested that propofol and sevoflurane have inconsistent effects on cerebral blood flow and cerebrovascular self-regulation. The purpose of this study is to compare changes in the optic nerve sheath diameter in patients undergoing laparoscopic gynecological surgery under anesthetic maintenance with propofol versus sevoflurane.MethodsThis study included 110 patients undergoing laparoscopic gynecological surgery with an estimated operative time of more than 2 h under general anesthesia. The study was a randomized controlled study. The optic nerve sheath diameter (ONSD) at various time points was measured by ultrasound, including when the patients entered the operating room (Tawake), after successful anesthesia induction and endotracheal intubation (Tinduction), when the body position was adjusted to the Trendelenburg position and the CO2 pneumoperitoneum pressure reached 14 mmHg, which was recorded as T0. Then, measurements were conducted every 15 min for the first 1 h and then once every hour until the end of the surgery (T15, T30, T45, T1h, T2h …), after the end of surgery and the tracheal tube was removed (Tend), and before the patients were transferred to the ward (Tpacu).ResultsA significant difference in optic nerve sheath diameter was found between two groups at T15, T30, T45 (4.64 ± 0.48 mm and 4.50 ± 0.29 mm, respectively, p = 0.031;4.77 ± 0.45 mm and 4.62 ± 0.28 mm, respectively, p = 0.036;4.84 ± 0.46 mm and 4.65 ± 0.30 mm, respectively, p = 0.012), while there was no significant difference at Tawake and other time points.ConclusionDuring laparoscopic gynecological surgery lasting more than 2 h, the optic nerve sheath diameter was slightly larger in the propofol group than that in the sevoflurane group in the first 45 min. No significant difference was observed between the two groups 1 h after surgery.Trial registrationclinicaltrials.gov, NCT03498235. Retrospectively registered 1 March 2018.The manuscript adheres to CONSORT guidelines.

Effects of different intraabdominal pressure levels on oxidative stress markers in laparoscopic cholecystectomy.

To evaluate the effect of laparoscopic cholecystectomy performed under different intraabdominal pressure on oxidative stress markers. This prospective, randomized, controlled study examined 90 consecutive healthy patients who underwent elective laparoscopic cholecystectomy with the diagnosis of symptomatic cholelithiasis. The patients were divided into three groups, 30 patients in each. Group 1 included patients who underwent laparoscopic cholecystectomy at a CO2 pneumoperitoneum pressure of 7 mmHg, Group 2 patients who underwent laparoscopic cholecystectomy at a CO2 pneumoperitoneum pressure of 10 mmHg, and Group 3 patients who underwent laparoscopic cholecystectomy at a CO2 pneumoperitoneum pressure of 13 mmHg. Blood samples were collected preoperatively, perioperatively, and postoperatively for measurement of the serum levels of ischemia modified albumin and an analysis of total antioxidant status and total oxidant status. Intra-group comparisons were made. Group 1 experienced a significant increase in the postoperative ischemia modified albumin values compared to preoperative ischemia modified albumin values (p=0.013). Group 2 experienced a significant decrease in the perioperative total antioxidant status values compared to preoperative and postoperative total antioxidant status values (p=0.009). Group 3 experienced a significant increase in the perioperative total oxidant status and oxidative stress index values compared to preoperative values (p<0.001). Group 3 experienced a significant increase in the perioperative and postoperative ischemia modified albumin values compared to preoperative values (p<0.001). Increased levels of oxidative stress markers were detected in patients who underwent laparoscopic cholecystectomy at a high intraabdominal pressure level.

Effects of Altered Intra-abdominal Pressure on the Upper Airway Collapsibility in a Porcine Model.

Background:Obstructive sleep apnea is strongly associated with obesity, particularly abdominal obesity common in centrally obese males. Previous studies have demonstrated that intra-abdominal pressure (IAP) is increased in morbid obesity, and tracheal traction forces may influence pharyngeal airway collapsibility. This study aimed to investigate that whether IAP plays a role in the mechanism of upper airway (UA) collapsibility via IAP-related caudal tracheal traction.Methods:An abdominal wall lifting (AWL) system and graded CO2 pneumoperitoneum pressure was applied to four supine, anesthetized Guizhou miniature pigs and its effects on tracheal displacement (TD) and airflow dynamics of UA were studied. Individual run data in 3 min obtained before and after AWL and obtained before and after graded pneumoperitoneum pressure were analyzed. Differences between baseline and AWL/graded pneumoperitoneum pressure data of each pig were examined using a Student's t-test or analysis of variance.Results:Application of AWL resulted in decreased IAP and significant caudal TD. The average displacement amplitude was 0.44 mm (P < 0.001). There were three subjects showed increased tidal volume (TV) (P < 0.01) and peak inspiratory airflow (P < 0.01); however, the change of flow limitation inspiratory UA resistance (Rua) was not significant. Experimental increased IAP by pneumoperitoneum resulted in significant cranial TD. The average displacement amplitude was 1.07 mm (P < 0.001) when IAP was 25 cmH2O compared to baseline. There were three subjects showed reduced Rua while the TV increased (P < 0.01). There was one subject had decreased TV and elevated Rua (P < 0.001).Conclusions:Decreased IAP significantly increased caudal TD, and elevated IAP significantly increased cranial TD. However, the mechanism of UA collapsibility appears primarily mediated by changes in lung volume rather than tracheal traction effect. TV plays an independent role in the mechanism of UA collapsibility.

Influence of carbon dioxide pneumoperitoneum on the growth hormone-insulin-like growth factor I axis in mid- and late-pregnancy rats.

We investigated the influence of carbon dioxide (CO2) pneumoperitoneum on the growth hormone(GH)-insulin-like growth factor I (IGF-I) axis in mid- and late-pregnancy Sprague-Dawley rats. A total of 48 mid-pregnancy rats were randomly assigned to one of three groups: anesthesia only (control group); 1-h CO2 pneumoperitoneum; or 2-h CO2 pneumoperitoneum. Blood samples were collected immediately after the procedure or in late pregnancy. Maternal concentration of serum GH and IGF-I was measured on enzyme-linked immunosorbent assay and compared between different groups. Under the same CO2 pneumoperitoneum pressure, serum GH and IGF-I concentration in the 2-h pneumoperitoneum group were significantly lower than those of the 1-h pneumoperitoneum group or the control group in both mid- and late pregnancy (P < 0.05), but there was no significant difference between the 1-h pneumoperitoneum group and the control group (P > 0.05). Serum GH and IGF-I concentrations were positively correlated in pregnant rats (R(2) = 0.3434, P < 0.05). Under the same CO2 pneumoperitoneum pressure, exposure duration was correlated with effect on maternal GH-IGF-I axis in mid- and late-pregnancy rats. Two h of exposure inhibited the GH-IGF-I axis in both mid- and late pregnancy, and therefore may restrict development of the placenta and fetus.

Optimizing working space in laparoscopy: CT measurement of the influence of small body size in a porcine model

IntroductionIn our continuing research into the determinants of laparoscopic working space, the influence of small body size was investigated. MethodsIn eight 6-kg pigs, the effects of intraabdominal CO2 pneumoperitoneum pressure (IAP), prestretching of the abdominal wall, and neuromuscular blockade (NMB) on laparoscopic working space volume and distances were studied. Computed tomography was used to measure working space during two stepwise abdominal insufflation-runs up to an IAP of 15mm Hg. Results were compared with data from earlier experiments in 20-kg pigs. ResultsCardiorespiratory parameters were stable up to an IAP of 8–10mm Hg. In 6-kg pigs working-space dimensions were five times smaller than in 20-kg pigs. Working-space volume, anteroposterior (AP) diameter and symphysis-diaphragm distance increased linearly up to an IAP of 8mm Hg. Above 8mm Hg, compliance decreased. Eighty percent of the total volume (618ml) and of AP diameter (3cm) at 15mm Hg had been achieved at an IAP of 10mm Hg. Prestretching by a first insufflation resulted in a statistically significant increase in working space volume and in AP diameter during the second insufflation. This effect was significantly larger than in 20-kg pigs. Neuromuscular blockade did not have a significant effect on working-space. ConclusionsWorking space in growing individuals is very limited. Eighty percent of the working space created by an IAP of 15mm Hg was already achieved at 10mm Hg, while cardiorespiratory side effects at an IAP of 8–10mm Hg seem acceptable. Prestretching of the abdominal wall significantly increased working space, even more so than in 20-kg pigs. As in 20-kg pigs, NMB had no significant effect on laparoscopic working space. Prestretching of the abdominal wall is a promising cheap, safe and easy strategy to increase laparoscopic working space, lessening the need for prolonged high-pressure pneumoperitoneum.

Impact of different pneumoperitioneal pressure on pathomorphism and function of intestines following laparoscopic radical gastrectomy

To investigate the influence of different pressures of CO2 pneumoperitioneum on pathomorphism and function of intestines following laparoscopic gastrectomy (LG). Forty-eight gastric cancer patients were prospectively enrolled in the study. Among them, 36 patients scheduled for elective LG were randomly assigned to low pressure group (LP), middle pressure (MP), and high pressure group (HP) with 12 cases in each group. The CO2 pneumoperitoneum pressure was maintained at 8-10 mmhg in LP, 11-13 mmhg in MP, and 14-16 mmhg in HP. The control group was open gastrectomy group (OG) in 12 cases. The intestinal pathomorphism and level of plasma D-lactic acid before, during and after operation, and postoperative intestinal function of four groups were examined and compared. There were no statistical differences in preoperative data among the four groups(all P>0.05). LG group was associated with a lower rate of surgical complications than OG (8.3% vs. 41.7%, P<0.05). No obvious damage of intestinal mucosa was found in OG group. Damage degree of intestinal mucosa after operation in LP, MP and HP groups was 0-1, 1-2, and 2-3 respectively. There was significant change in intestinal pathomorphism after operation in both HP and MP groups. The levels of D-lactic acid before operation were not significantly different among all the four groups, but increased significantly in each group after operation (all P<0.05). HP group had the highest level of plasma D-lactic acid and presented with delayed bowel sound return (4.5 d), time to first flatus (5.4 d), and intake (6.0 d) as compared to the other 3 groups (all P<0.05). Laparoscopic radical gastrectomy is safe and minimally invasive. Higher pneumoperitoneal pressure is harmful to the recovery of intestinal mucosa and function. Therefore the pneumoperitioneum pressure should be maintained as low as possible under clear visualization during operation.

Effect of CO2 pneumoperitoneum on the expression of the chemokine receptors CXCR4 and CCR7 in colorectal carcinoma cells in vitro

Background The ability of pneumoperitoneum in laparoscopic surgery to promote proliferation and metastasis of colorectal cancer has become a focus of research in the field of minimally invasive surgery. The aim of this research was to investigate the effect of CO2 pneumoperitoneum under different pressures and exposed times on the expression of chemokine receptors in colorectal carcinoma cells. Methods We constructed an in vitro pneumoperitoneum model. SW480 colon carcinoma cells were exposed to CO2 pneumoperitoneum under different pressures (6, 9, 12, and 15 mmHg) for 1, 2, and 4 hours. These cells were then cultivated under the same conditions as normal SW480 colon carcinoma cells without CO2 pneumoperitoneum (control group), treated at 37°C, and 5% CO2. The expression of the chemokine receptors CXC receptor 4 (CXCR4) and chemokine C receptor 7 (CCR7) was detected by immunocytochemistry and reverse transcriptase polymerase chain reaction after being cultivated for 0, 24, 48, and 72 hours. Results Immunocytochemistry showed that CXCR4 expression in SW480 cells was significantly decreased in the 6, 9, 12, and 15 mmHg CO2 pneumoperitoneum-treated groups for the same exposure times compared with controls (P &lt;0.05). CCR7 expression in SW480 cells was significantly decreased in the 12 and 15 mmHg CO2 pneumoperitoneum-treated groups compared with controls (P &lt;0.05). CXCR4 and CCR7 expression increased up to the level of the control group after 24 and 48 hours (P &gt;0.05). If the CO2 pneumoperitoneum pressure increased, CXCR4 and CCR7 expression decreased at all exposure times. If the CO2 pneumoperitoneum exposure time prolonged, there were no significant differences in CXCR4 and CCR7 expression under the same pressure. Under all exposure times, CXCR4 and CCR7 mRNA expression was significantly decreased in the 6, 9, 12, and 15 mmHg CO2 pneumoperitoneum-treated groups (P &lt;0.05) compared with controls, and it increased up to the level of controls after being cultivated for 48 hours (P &gt;0.05). If the CO2 pneumoperitoneum pressure increased (with all exposure times) and exposure time prolonged (under the same pressure), there were no significant differences in CXCR4 and CCR7 expression. Conclusions CXCR4 and CCR7 expression is temporarily affected after continuous CO2 pneumoperitoneum treatment. The high pressure of CO2 pneumoperitoneum plays an important role in suppressing the expression of these chemokine receptors. Different lengths of time of exposure to a CO2 pneumoperitoneum-like environment do not change CXCR4 and CCR7 expression.

Toleration to CO2 pneumoperitoneum pressure in mild and severe hydronephrosis of rabbits

Objective To observe the toleration to CO2 pneumoperitoneum pressure in mild and severe hydronephrosis of rabbits.Methods Fifty-six New Zealand White male rabbits were randomly allocated in three groups:normal (N,n =16),mild hydronephrosis (M,n =20) and severe hydronephrosis (S,n =20).The mild and severe hydronephrosis was induced by ureteral tube method.The rabbits in N group were treated with 6,9,12,and 15 mmHg (1 mmHg =0.133 kPa) CO2 pneumoperitoneum pressure,and those in M and S groups were treated with 0,6,9,12 and 15 mm Hg CO2 pneumoperitoneum pressure.The time of pneumoperitoneum pressure was 1 h.The kidneys were harvested for measurement of super oxide dismutase (SOD),malonaldehyde (MDA) and apoptosis index (AI) of tubular cells after 24 h.Results In N group,SOD content was (17.46±1.17),(17.40±0.83),(16.92±1.53) and (12.91 ± 1.30) U/mg,MDA content was (0.13 ±0.03),(0.14 ±0.02),(0.13 ±0.01) and (0.38 ± 0.04) mmol/g,AI was (5.23 ± 1.05),(5.51 ±0.90),(6.13 ±0.90)％ and (41.60 ±3.62)％ respectively.SOD content was significantly decreased,MDA and AI were significantly increased in 15 mmHg as compared with those in 6,9,12 mmHg (P ＜ 0.05).In M group,SOD content was (17.17 ± 1.33),(16.55±1.53),(16.27 ±2.02),(15.98±1.10) and (11.84±0.86) U/mg,MDA content was (0.15 ±0.01),(0.15 ±0.02),(0.15 ±0.01),(0.16 ±0.02) and (0.44 ±0.04) mmol/g,AI was (7.83 ± 1.19),(8.43 ± 1.05),(8.63 ± 0.70),(9.60 ± 1.58) ％ and (43.03 ± 4.39) ％,respectively.In S group,SOD content was (16.52 ± 0.68),(16.43 ±.0.87),(10.54 ± 0.59),(10.26 ±.0.69) and (10.13±0.79) U/mg,MDA content was (0.18 ±0.01),(0.18 ±0.03),(0.44 ±0.06),(0.46 ±0.0) and (0.47 ±0.04) mmol/g,AI was (10.53 ±2.05),(11.68 ±1.69),(44.73 ±3.46),(47.33 ±6.22)％ and (48.28 ±2.85)％,respectively.In M and S groups,SOD content was significantly decreased,and MDA content and AI were significantly decreased (P ＜ 0.05) when the pneumoperitoneum pressure was increased to 15 and 9 mmHg respectively.Conclusion Pressure should be controlled and reduced when performing pneumoperitoneum procedures in the context of kidneys with severe hydronephrosis. Key words: Hydronephrosis ; Pneumoperitoneum pressure; Toleration