Elevated Intra-abdominal Pressure Research Articles

Umbilical hernia in cirrhotic patients: conservative treatment or surgery?

Background: Background: Ascites is a common complication in patients with cirrhosis, and elevated intraabdominal pressure can lead to the development of abdominal wall hernias, particularly in patients with latent umbilical defects. Objectives: The aim of this study was to report the incidence and benefits of elective surgery for the management of umbilical hernias in cirrhotic patients with ascites. Material and methods: Between January 2015 and January 2019 15 patients with symptomatic umbi- lical hernia underwent elective surgery in a public hospital; 100% were men with a history of alcoho- lism and were hospitalized due to liver cirrhosis. The defect was closed, and a polypropylene mesh was placed in the supra-aponeurotic plane in most cases. Results: The preoperative risk was estimated using the Child-Pugh score. Ascites was evacuated in all the cases. Patients were followed-up every 30 days during the first 6 months and then twice a year. There were no hernia recurrences. Two patients were lost to follow-up 12 months after surgery and 1 patient died 9 months after the procedure due to progression of cirrhosis. Conclusions: Patients with liver cirrhosis and umbilical hernia should undergo elective surgery. Watchful waiting is associated with higher risk of hernia rupture and high morbidity and mortality.

Impact of Different Positive End-Expiratory Pressures on Lung Mechanics in the Setting of Moderately Elevated Intra-Abdominal Pressure and Acute Lung Injury in a Porcine Model.

The effects of a moderately elevated intra-abdominal pressure (IAP) on lung mechanics in acute respiratory distress syndrome (ARDS) have still not been fully analyzed. Moreover, the optimal positive end-expiratory pressure (PEEP) in elevated IAP and ARDS is unclear. In this paper, 18 pigs under general anesthesia received a double hit lung injury. After saline lung lavage and 2 h of injurious mechanical ventilation to induce an acute lung injury (ALI), an intra-abdominal balloon was filled until an IAP of 10 mmHg was generated. Animals were randomly assigned to one of three groups (group A = PEEP 5, B = PEEP 10 and C = PEEP 15 cmH2O) and ventilated for 6 h. We measured end-expiratory lung volume (EELV) per kg bodyweight, driving pressure (ΔP), transpulmonary pressure (ΔPL), static lung compliance (Cstat), oxygenation (P/F ratio) and cardiac index (CI). In group A, we found increases in ΔP (22 ± 1 vs. 28 ± 2 cmH2O; p = 0.006) and ΔPL (16 ± 1 vs. 22 ± 2 cmH2O; p = 0.007), with no change in EELV/kg (15 ± 1 vs. 14 ± 1 mL/kg) when comparing hours 0 and 6. In group B, there was no change in ΔP (26 ± 2 vs. 25 ± 2 cmH2O), ΔPL (19 ± 2 vs. 18 ± 2 cmH2O), Cstat (21 ± 3 vs. 21 ± 2 cmH2O/mL) or EELV/kg (12 ± 2 vs. 13 ± 3 mL/kg). ΔP and ΔPL were significantly lower after 6 h when comparing between group C and A (21 ± 1 vs. 28 ± 2 cmH2O; p = 0.020) and (14 ± 1 vs. 22 ± 2 cmH2O; p = 0.013)). The EELV/kg increased over time in group C (13 ± 1 vs. 19 ± 2 mL/kg; p = 0.034). The P/F ratio increased in all groups over time. CI decreased in groups B and C. The global lung injury score did not significantly differ between groups (A: 0.25 ± 0.05, B: 0.21 ± 0.02, C: 0.22 ± 0.03). In this model of ALI, elevated IAP, ΔP and ΔPL increased further over time in the group with a PEEP of 5 cmH2O applied over 6 h. This was not the case in the groups with a PEEP of 10 and 15 cmH2O. Although ΔP and ΔPL were significantly lower after 6 hours in group C compared to group A, we could not show significant differences in histological lung injury score.

Congestive nephropathy: a neglected entity? Proposal for diagnostic criteria and future perspectives.

Venous congestion has emerged as an important cause of renal dysfunction in patients with cardiorenal syndrome. However, only limited progress has been made in differentiating this haemodynamic phenotype of renal dysfunction, because of a significant overlap with pre‐existing renal impairment due to long‐term hypertension, diabetes, and renovascular disease. We propose congestive nephropathy (CN) as this neglected clinical entity. CN is a potentially reversible subtype of renal dysfunction associated with declining renal venous outflow and progressively increasing renal interstitial pressure. Venous congestion may lead to a vicious cycle of hormonal activation, increased intra‐abdominal pressure, excessive renal tubular sodium reabsorption, and volume overload, leading to further right ventricular (RV) stress. Ultimately, renal replacement therapy may be required to relieve diuretic‐resistant congestion. Effective decongestion could preserve or improve renal function. Congestive acute kidney injury may not be associated with cellular damage, and complete renal function restoration may be a confirmatory diagnostic criterion. In contrast, a persistently low renal perfusion pressure might induce renal dysfunction and histopathological lesions with time. Thus, urinary markers may differ. CN is mostly seen in biventricular heart failure but may also occur secondary to pulmonary arterial hypertension and elevated intra‐abdominal pressure. An increase in central venous pressure to >6 mmHg is associated with a steep decrease in glomerular filtration rate. However, the central venous pressure range that can provide an optimal balance of RV and renal function remains to be determined. We propose criteria to identify cardiorenal syndrome subgroups likely to benefit from decongestive or pulmonary hypertension‐specific therapies and suggest areas for future research.

Mechanism and Management of Fentanyl-Induced Cough.

Fentanyl-induced cough (FIC) often occurs after intravenous bolus administration of fentanyl analogs during induction of general anesthesia and analgesia procedure. The cough is generally benign, but sometimes it causes undesirable side effects, including elevated intra-abdominal, intracranial or intraocular pressure. Therefore, understanding the related mechanisms and influencing factors are of great significance to prevent and treat the cough. This paper reviews the molecular mechanism, influencing factors and preventive administration of FIC, focusing on the efficacy and side effects of various drugs in inhibiting FIC to provide some medical reference for anesthesiologists.

Intra-abdominal Pressure Has a Good Predictive Power for 28-Day Mortality: A Prospective Observational Study Conducted in Critically Ill Children.

Objective: Elevated intra-abdominal pressure (IAP) is associated with organ dysfunction in critically ill children. Thus far, the predictive value of IAP for mortality remains unknown. Moreover, only few studies determined normal IAP values in pediatric intensive care unit (PICU) children. This study aimed to determine the predictive value of IAP for mortality and calculate normal IAP values in PICU patients.Methods: This prospective observational study was conducted in two PICUs of two tertiary care university teaching hospitals. Patients admitted to the PICU between December 2013 and November 2015 were included. IAP was determined by bladder pressure measurements performed every 8 h until 48 h or until PICU discharge. All patients (except neonatal patients) aged ≤ 14 years who were admitted to the PICUs and had no history of chemical neuromuscular blockade use, neurogenic bladder, or bladder surgery were enrolled. Binary logistic regression was used to analyze the predictive value of IAP for 28-day mortality. Receiver operating characteristic curves were generated to evaluate the prediction effect of IAP.Results: Overall, 229 patients were enrolled. IAP (hazard ratio 1.09, 95% confidence interval [CI] 1.029–1.161, P = 0.004) and lactic acid (hazard ratio 3.04, 95% CI 1.769–5.21, P < 0.001) were independent predictors of 28-day mortality. Additionally, IAP had good predictive power for 28-day mortality, with an area under the curve of 0.74. The optimal cutoff point was 12.13 mmHg (sensitivity 0.58, specificity 0.80). The Youden index was 0.38.Furthermore, 111 (48.47%) patients without high-risk factors or clinical manifestations of IAH were analyzed to determine normal IAP values, which were 7.57 ± 2.85 mmHg (range, 1.98–13.16 mmHg). There were no significant differences in normal IAP values according to different diseases, sex, age, weight, or body mass index (BMI).Conclusions: IAP has good predictive power for 28-day mortality. The optimal IAP cutoff point is 12.13 mmHg. The IAP reference range is 2.0–13.2 mmHg, which was not associated with factors such as sex, age, weight, and BMI in PICU children. We recommend that IAP be included in critical illness scoring systems in the future. IAP >12.13 mmHg may be more suitable for IAH definition in PICU patients.

Evaluation of the effects of medial saphenous venous pressures as an indirect method of measurement of intra-abdominal pressures in the horse.

To evaluate the effect of changes in intra-abdominal pressure (IAP) on medial saphenous venous pressure (MSVP) and hemodynamics in normal horses. Experimental, in-vivo study. University Teaching Hospital. Convenience sample of 7 mixed breed horses; 5 geldings, and 2 mares. Pneumoperitoneum was induced in horses under standing sedation with carbon dioxide gas using a laparoscopic insufflator for a total of 60 minutes to simulate clinical elevation in IAP. Pressure was increased stepwise to 20mm Hg over 30 minutes, and maintained at that pressure for 30 minutes to evaluate the effect of sustained intra-abdominal hypertension. The MSVP and vital parameters were recorded, along with direct arterial blood pressure from the transverse facial artery. As IAP increased, MSVP increased in a stepwise manner, in concert with changes in IAP. The consistency in measurement between MSVP and IAP was high (intraclass correlation coefficient=0.92; P<0.001) and repeated measures correlation was excellent (r=0.98; P<0.001). Heart rate was unchanged over the course of the experiment (P=0.09), however, respiratory rate increased with increasing IAP (P<0.001). Arterial blood pressure also increased with insufflation (P<0.001), with a significant difference at an IAP of 15mm Hg (P=0.04). This report provides preliminary data demonstrating a strong correlation between equine MSVP and changes in IAP, similar to that observed in other species. Further investigations are needed to evaluate this relationship, and to confirm these results in clinical patients.

Vasopressin Mediated Hemodynamic Response to Intracranial Hypertension during Acute Elevations of Intraabdominal Pressure

Vasopressin Mediated Hemodynamic Response to Intracranial Hypertension during Acute Elevations of Intraabdominal Pressure

Intra-abdominal Hypertension and Abdominal Compartment Syndrome in patients undergoing emergency laparotomy

Objective: The objectives of the Prospective observational study were to identify the frequency of abdominal compartment syndrome and intraabdominal hypertension in patients undergoing emergency laparotomy for trauma and peritonitis and to determine the impact of raised intraabdominal pressure on the overall morbidity and mortality.&#x0D; Materials and Methods: The study was conducted in the department of surgery Benazir Bhutto Hospital Rawalpindi. From June 2013 to May 2014 a total of 50 patients undergoing emergency laparotomy were included. IAP was measured preoperatively then postoperatively at 0, 6, 24 hours, and the findings were recorded on a specially designed preform. The patients having higher IAP were further evaluated up to 72 hours. All vitals, urine output, oxygen saturation, serum urea, creatinine were noted. The main outcomes were duration of hospital stay, the occurrence of burst abdomen, and mortality.&#x0D; Results: At the preoperative level the incidence of IAH was 86%. The mortality association with IAH at 6 hours postoperatively was quite significant (P&lt;0.029). The incidence of postoperative ACS was 5% among the total patients and it was 15.6% in trauma patients. No significant association was found between IAP and occurrence of burst abdomen at any level (P values 0.4, 0.26, 0.53, 0.58 at intervals preoperatively, 0, 6, 24 hours postoperative respectively. &#x0D; Conclusion: Intraabdominal pressure is an important factor that predicts the mortality of patients undergoing emergency laparotomy. It should be carefully monitored and managed accordingly to avoid the detrimental effects on virtually all organ systems. Abdominal decompression in significantly elevated intraabdominal pressure reverts the physiological derangement of Intrabdominal hypertension.

Evaluation of the effects of intraabdominal hypertension on equine central venous pressure.

To evaluate the effect of changes in intraabdominal pressure (IAP) on central venous pressure (CVP) in normal horses. Experimental, in vivo study. University Teaching Hospital. Convenience sample of 7 mixed breed horses-5 geldings and 2 mares. Pneumoperitoneum was induced in horses under standing sedation with carbon dioxide gas using a laparoscopic insufflator for a total of 60 minutes to simulate clinical elevation in IAP. Pressure was increased stepwise to 20mm Hg over 30 minutes, and maintained at that pressure for 30 minutes to evaluate the effect of sustained intraabdominal hypertension. CVP was obtained from the cranial vena cava, concurrent with pressure obtained from the peritoneal cavity. CVP increased as IAP increased up to 12mm Hg, and declined as IAP increased further. The changes in CVP over time were significantly different (P< 0.03). Repeated measures correlation was positive, and highest, for mean CVP as IAP increased from 0 to 12mm Hg (r=.70; 95% CI, .43-.85; P< 0.0001). Correlation of mean CVP with insufflation pressure became negative as IAP increased further from 15 to 20mm Hg (r=-.47; 95% CI, -.66 to -.21; P= 0.0006). This report provides preliminary data demonstrating a biphasic trend in equine CVP caused by changes in IAP, similar to that observed in other species. Further investigations are needed to evaluate this trend and to confirm these results in clinical patients.

Impact of Pneumoperitoneum on the Development of Acute Kidney Injury: Comparison Between Normal and Diabetic Rats

Minimally invasive surgery is considered the gold-standard approach for many surgical procedures. However, it requires CO2 insufflation and elevated intra-abdominal pressure (IAP), which may result in adverse pulmonary, cardiovascular, gastrointestinal, and renal changes. The kidneys are highly sensitive to pressure changes, where risk factors such as severe infection, dehydration, older age, and chronic kidney disease may aggravate the likelihood for the development of acute kidney injury (AKI). Unfortunately, the impact of diabetes mellitus on the deleterious effects of elevated IAP-induced AKI was not fully studied so far. The present study was designed to examine the effect of pneumoperitoneum on renal function and the development of AKI in diabetic rats. Sprague Dawley rats were divided into 2 groups: control (nondiabetic) rats (n=7) and diabetic rats (n=10). A Veress needle was introduced through the supravesical incision where inflating CO2 allowing the IAP to be increased to the desired pressures 7, 10, and 14 mm Hg for 45 minutes each and at the end of the experiment, the pressure was deflated to zero. During each pressure point, hemodynamic parameters were recorded and urine and blood samples were collected for analysis. The baseline values of renal hemodynamic were significantly lower in diabetic rats. There were no major statistically significant changes from baseline in urinary flow, urinary sodium excretion (UNaV), glomerular filtration rate, and renal plasma flow during 7 mm Hg pressure in both groups. When the IAP was further elevated, a significant deterioration of these parameters was recorded. This trend was more pronounced among diabetic rats. When examining urinary neutrophil gelatinase-associated lipocalin, a linear correlation was observed between the IAP and the biomarker level. This correlation was more significant in the diabetic group. The present study demonstrated a direct correlation between IAP elevation and the development of AKI. Diabetic rats were more sensitive to the deleterious effect of pneumoperitoneum, where urinary neutrophil gelatinase-associated lipocalin levels may be used as a future biomarker to predict postoperative AKI, especially in patients with diabetes.

A finite element analysis of the intra-abdominal pressure and paraspinal muscle compartment pressure interaction through the thoracolumbar fascia

Thoracolumbar fascia involvement is often neglected when studying the biomechanics of the spine. The purpose of this study was to develop, validate, and explore the use of a novel finite element model of the spine, inclusive of the Thoracolumbar Fascia, Paraspinal Muscular Compartment (PMC) and the Intra-Abdominal Pressure (IAP) based on published clinical studies. Reaction forces were acquired at five critical anatomical locations. Results showed that elevated IAP decreased the posterior force and balanced the anterior forces when PMC pressure was asymmetric. This novel finite element study demonstrated a link between the TLF compartments supporting its involvement in spinal stability.

Effect of moderate elevated intra-abdominal pressure on lung mechanics and histological lung injury at different positive end-expiratory pressures.

Intra-abdominal hypertension (IAH) is a well-known phenomenon in critically ill patients. Effects of a moderately elevated intra-abdominal pressure (IAP) on lung mechanics are still not fully analyzed. Moreover, the optimal positive end-expiratory pressure (PEEP) in elevated IAP is unclear. We investigated changes in lung mechanics and transformation in histological lung patterns using three different PEEP levels in eighteen deeply anesthetized pigs with an IAP of 10 mmHg. After establishing the intra-abdominal pressure, we randomized the animals into 3 groups. Each of n = 6 (Group A = PEEP 5, B = PEEP 10 and C = PEEP 15 cmH2O). End-expiratory lung volume (EELV/kg body weight (bw)), pulmonary compliance (Cstat), driving pressure (ΔP) and transpulmonary pressure (ΔPL) were measured for 6 hours. Additionally, the histological lung injury score was calculated. Comparing hours 0 and 6 in group A, there was a decrease of EELV/kg (27±2 vs. 16±1 ml/kg; p<0.05) and of Cstat (42±2 vs. 27±1 ml/cmH2O; p<0.05) and an increase of ΔP (11±0 vs. 17±1 cmH2O; p<0.05) and ΔPL (6±0 vs. 10±1 cmH2O; p<0.05). In group B, there was no significant change in EELV/kg (27±3 vs. 24±3 ml/kg), but a decrease in Cstat (42±3 vs. 32±1 ml/cmH20; p<0.05) and an increase in ΔP (11±1 vs. 15±1 cmH2O; p<0.05) and ΔPL (5±1 vs. 7±0 cmH2O; p<0.05). In group C, there were no significant changes in EELV/kg (27±2 vs. 29±3 ml/kg), ΔP (10±1 vs. 12±1 cmH2O) and ΔPL (5±1 vs. 7±1 cmH2O), but a significant decrease of Cstat (43±1 vs. 37±1 ml/cmH2O; p<0.05). Histological lung injury score was lowest in group B. A moderate elevated IAP of 10 mmHg leads to relevant changes in lung mechanics during mechanical ventilation. In our study, a PEEP of 10 cmH2O was associated with a lower lung injury score and was able to overcome the IAP induced alterations of EELV.

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

Trans-esophagogastric junction pressure gradients during straight leg raise maneuver on high-resolution manometry associate with large hiatus hernias.

Straight leg raise (SLR) while supine increases intra-abdominal pressure. We hypothesized that elevations in intra-abdominal pressure would transmit into the thoracic cavity if the esophagogastric junction (EGJ) was disrupted. Consecutive patients undergoing esophageal HRM were included if they had adequate SLR (hip flexion with knees extended for≥5seconds while supine). EGJ morphology was subtyped based on lower esophageal sphincter (LES) and crural diaphragm (CD) location (type 1: LES and CD overlap; type 2: separation of<3cm; type 3: separation of≥3cm). EGJ tone was assessed using EGJ contractile integral (EGJ-CI). HRM studies were analyzed according to Chicago Classification v3.0. Mean and peak intra-thoracic and abdominal pressures were measured at baseline and during SLR using on-screen software tools. Trans-EGJ gradients were compared, and pressure gradient<1mmHg denoted the equalization of pressures. Of 430 patients, 248 (57.5±0.9years, 69.4% F) completed SLR. EGJ morphology was type 1 in 122 (49.2%), type 2 in 56 (22.6%) and type 3 in 40 (16.1%). In types 1 and 2 EGJ, neither the mean nor peak trans-EGJ pressure gradient changed with SLR (P≥.17 for each). In contrast, in type 3 EGJ, peak pressure gradient decreased significantly following SLR (3.5±1.8mmHg vs. -8.6±4.8mmHg, P=.01). More type 3 EGJ patients equalized peak (65%) pressures across EGJ compared with types 1 and 2 (27%, P<.001). The evaluation of intra-abdominal and intra-thoracic pressures with SLR during esophageal HRM can provide evidence of physiological disruption of the EGJ barrier.

Factors associated with increased intra-abdominal pressure in patients undergoing cardiac surgery.

The aim of this study was to investigate the intra-abdominal pressure changes and risk factors associated with increased intra-abdominal pressure in patients undergoing cardiac surgery. Between July 2016 and January 2017, a total of 100 patients (74 males, 26 females; mean age 55.9±14.3 years; range, 19 to 75 years) who underwent cardiac surgery under cardiopulmonary bypass were included in the study. Patients" data including demographic and clinical characteristics and intra- and postoperative data were recorded. Intra-abdominal pressure was measured via a urinary catheter after anesthesia induction, on admission to the intensive care unit, and at postoperative 12 and 24 h. The patients were divided into two groups according to the intraabdominal pressure as Group 1 (≥12 mmHg; n=49) and Group 2 (<12 mmHg; n=51). In the univariate regression analysis, high intra-abdominal pressure was related to intra-abdominal pressure measured after anesthesia induction (Odds Ratio =0.70, p=0.001), age (odds ratio=0.95, p=0.004), hypertension (odds ratio=4.51, p=0.0001), duration of cardiopulmonary bypass (odds ratio=0.97, p=0.0001), intraoperative lactate levels (odds ratio=0.53, p=0.0001), use of red blood cells (odds ratio=0.24, p=0.0001), use of dopamine (odds ratio=0.21, p=0.002), dobutamine (odds ratio=0.28, p=0.005), use of noradrenaline (odds ratio=0.25, p=0.016), postoperative lactate levels (odds ratio=0.60, p=0.0001), duration of cross-clamp (odds ratio=0.97, p=0.0001), atrial fibrillation (odds ratio=5.89, p=0.004), and acute kidney injury (odds ratio=8.33, p=0.048). In the multivariate analysis, the intra-abdominal pressure at baseline (odds ratio=0.70, p=0.045), age (odds ratio=0.93, p=0.032), hypertension (odds ratio=6.87, p=0.023), duration of cardiopulmonary bypass (odds ratio=0.98, p=0.062), intraoperative lactate levels (odds ratio=0.57, p=0.035), and use of red blood cells (odds ratio=0.19, p=0.003) remained statistically significant. Our study results suggest that age, hypertension, duration of cardiopulmonary bypass, intraoperative lactate levels, and use of red blood cells are risk factors associated with elevated intra-abdominal pressure in patients undergoing cardiac surgery. Increased awareness of these risk factors and the addition of intra-abdominal pressure measurement to the standard follow-up scheme in patients with variable hemodynamics, low cardiac output, and high lactate levels in the intensive care unit may be useful in early diagnosis of complications and in decreasing morbidity.

The effect of laparoscopic pre- and postconditioning on pneumoperitoneum induced injury of the peritoneum.

Pneumoperitoneum, widely used in laparoscopic surgery increases the intraabdominal pressure, leading to hypoperfusion of the abdominal organs, and promoting the buildup of reactive oxygen species(ROS) and inflammatory cytokines which in turn impairs the body postoperatively. Aim of our investigation was to evaluate the potential protective effects of short ischemic episodes on ischemic damages. 70 Wistar rats were used, divided into 7 groups: 1st group sham, 2nd group pneumoperitoneum with 5 mmHg, 3rd group preconditioning with 5 mmHg, 4th group: postconditioning with 5 mmHg, 5th group pneumoperitoneum with 10 mmHg, 6th group: preconditioning with 10 mmHg, 7th group postconditioning with 10 mmHg. Pneumoperitoneum was created by Veres needle. Oxidative stress parameters: malondialdehyde (MDA) concentration, reduced glutathione (GSH), sulfhydril (SH-), myeloperoxidase (MPO) levels and superoxide-dismutase (SOD) activity were measured. We measured TNF-α and IL-6 concentrations. We monitored the activation of anti- and proapoptotic common signaling pathways (bax, bcl-2, p53) during the early phase of reperfusion. Histology was made from kidney samples. GSH concentrations were significantly reduced, MDA concentrations were significantly higher in each group compared to the Sham. SOD enzyme: a pressure of 10 mmHg elicited significantly greater damage than 5 mmHg. There was a significantly higher SOD activity in group 10 mmHg IPC compared to 10 mmHg. We found that the expression of bax was considerably higher in the none conditioned groups. Noticeably higher expression of anti-apoptotic bcl-2 level was measured in 10 mmHg IPC and 10 mmHg IPoC groups. In case of p53 expression: significant decrease could be seen in groups 10 mmHg IPC and 10 mmHg IPoC compared to the 10 mmHg group. Based on our results, the elevated intraabdominal pressure due to pneumoperitoneum induces oxidative stress, which is dependent on the applied pressure. Mostly precondiotioning - but also postconditioning - reduces surgical stress following laparoscopic procedures. In order to explore its mechanism it requires further investigations.

Preoperative Progressive Pneumoperitoneum Enables Defect Closure and Laparoscopic Repair of Large Parastomal Hernias.

Preoperative progressive pneumoperitoneum (PPP) has not been reported in the management of parastomal hernias; therefore, the present study evaluated its effectiveness in the surgical management of large parastomal hernias. This prospective, observational study included 23 consecutive patients with large parastomal hernias who underwent PPP between January 2016 and September 2018. The volume of parastomal hernia (VPH), volume of the abdominal cavity (VAC), and the VPH/VAC ratio were measured before and after PPP using abdominal computed tomography scan data. All the hernias were repaired by a laparoscopic or laparoscopic-open-laparoscopic approach using the intraperitoneal Sugarbaker technique. Before and after PPP, the mean VPH was 1442 and 1581 mL (P<0.01), and the mean VAC was 5667 and 9194 mL (P<0.01). The VAC increased by 3527 mL (P<0.01) and was greater than the mean VPH before PPP. The VPH/VAC ratio after PPP was reduced at an average of 8.1% (P<0.01). Fascial closure was achieved in all patients, with no clinical evidence of elevated intra-abdominal pressures. The mean follow-up was 24 months (13 to 40 mo), and, to date, no hernia recurrences have been reported in these patients. PPP is a feasible and useful tool in the surgical management of large parastomal hernias. It passively expands the abdominal volumes, thereby resulting in respiratory adaptation to elevated intra-abdominal pressures.

Abdominal compartment syndrome: Often overlooked conditions in medical intensive care units.

Intra-abdominal hypertension (IAH) and abdominal compartment syndrome are well recognized entities among surgical patients. Nevertheless, a number of prospective and retrospective observational studies have shown that IAH is prevalent in about half of the critically ill patients in the medical intensive care units (ICU) and has been widely recognized as an independent risk factor for mortality. It is alarming to note that many members of the critical care team in medical ICU are not aware of the consequences of untreated IAH and the delay in making the diagnosis leads to increased morbidity and mortality. Frequently it is underdiagnosed and undertreated in this patient population. Elevated intra-abdominal pressure decreases the blood flow to the kidneys and other abdominal viscera and also results in reduced cardiac output and difficulties in ventilating the patient because of increased intrathoracic pressure. When intraabdominal hypertension is not promptly recognized and treated, it leads to abdominal compartment syndrome, multiorgan dysfunction syndrome and death. Large volume fluid resuscitation is very common in medical ICU patients presenting with sepsis, shock and other inflammatory conditions like pancreatitis and it is one of the major risk factors for the development of intra-abdominal hypertension. This article presents an overview of the epidemiology, definitions, risk factors, pathophysiology and management of IAH and abdominal compartment syndrome in critically ill medical ICU patients.

Intra-abdominal pressure may be elevated in patients with open abdomen after emergent laparotomy.

To estimate the change in intra-abdominal pressure (IAP) among critically ill patient who were left with open abdomen and temporary abdominal closure after laparotomy, during the first 48h after admission. A cohort study in a single ICU in a tertiary care hospital. All adult patients admitted to the ICU after emergent laparotomy for acute abdomen or trauma, who were left with temporary abdominal closure (TAC), were included. Patients were followed up to 48h. IAP was routinely measured at 0, 6, 12, 24, and 48h after admission to ICU. Thirty-nine patients were included, 34 were operated due to acute abdomen and 5 due to abdominal trauma. Seventeen patients were treated with skin closure, 13 with Bogota bag, and 9 with negative pressure wound therapy (NPWT). Eleven patients (28.2%) had IAP of 15mmHg or above at time 0, (mean pressure 19.0 ± 3.0mmHg), and it dropped to 12 ± 4mmHg within 48h (p < 0.01). Reduction in lactate level (2.4 ± 1.0 to 1.2 ± 0.2mmol/L, p < 0.01) and increase in PaO2/FiO2 ratio (163 ± 34 to 231 ± 83, p = 0.03) were observed as well after 48h. This is the first large report of IAP in open abdomen. Elevated IAP may be measured in open abdomen and may subsequently relieve after 48h.

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.