Prevalence of increased intra-abdominal pressure and its impact on renal function in acute decompensated heart failure: A prospective pilot study

BACKGROUND

Intra-abdominal pressure (IAP) is a frequently overlooked aspect in clinical assessment that can have a significant impact on organ dysfunction in patients with acute decompensated heart failure (ADHF).

AIMS

We aimed to investigate dynamics of IAP in patients with ADHF and its impact on diuretic response.

METHODS

We conducted a prospective observational pilot study on a group consisting of 30 patients admitted for ADHF. In every individual IAP measurement, blood and urine samples were taken upon admission, on the second and third days of hospitalization.

RESULTS

The study showed a high (63.3%) prevalence of intra-abdominal hypertension (IAH) defined as IAP ≥12 mm Hg upon admission, while only roughly 13% had signs of ascites. We observed poorer diuresis on the first day of hospitalization in the IAH group (P = 0.03). IAP was negatively correlated with urine output (P = 0.01) and positively correlated with urine osmolality (P = 0.03) on the first day of hospitalization. During follow-up, there was a significant decrease in IAP in patients with IAH upon admission who received standard decongestive therapy.

CONCLUSIONS

The study shows a high prevalence of IAH in patients admitted for ADHF, even in individuals who do not present symptoms of abdominal congestion. Established correlation between IAP, reduced diuresis, and increased urine osmolality, despite achieving target natriuresis, contributes novel insights into the understanding of pathomechanisms underlying diuretic resistance in ADHF.

A Custom-Tailored Multichannel Pressure Monitoring System Designed for Experimental Surgical Model of Abdominal Compartment Syndrome

In experimental medicine, a wide variety of sensory measurements are used. One of these is real-time precision pressure measurement. For comparative studies of the complex pathophysiology and surgical management of abdominal compartment syndrome, a multichannel pressure measurement system is essential. An important aspect is that this multichannel pressure measurement system should be able to monitor the pressure conditions in different tissue layers, and compartments, under different settings. We created a 12-channel positive-negative sensor system for simultaneous detection of pressure conditions in the abdominal cavity, the intestines, and the circulatory system. The same pressure sensor was used with different measurement ranges. In this paper, we describe the device and major experiences, advantages, and disadvantages. The sensory systems are capable of real-time, variable frequency sampling and data collection. It is also important to note that the pressure measurement system should be able to measure pressure with high sensitivity, independently of the filling medium (gas, liquid). The multichannel pressure measurement system we developed was well suited for abdominal compartment syndrome experiments and provided data for optimizing the method of negative pressure wound management. The system is also suitable for direct blood pressure measurement, making it appropriate for use in additional experimental surgical models.

Evaluation of the TraumaGuard Balloon-in-Balloon Catheter Design for Intra-Abdominal Pressure Monitoring: Insights from Pig and Human Cadaver Studies

Introduction: Intra-abdominal pressure (IAP) monitoring is crucial for the detection and prevention of intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS). In the 1970s, air-filled catheters (AFCs) for urodynamic studies were introduced as a solution to overcome the limitations of water-perfused catheters. Recent studies have shown that for correct IAP measurement with traditional AFC, the bladder needs to be primed with 25 mL of saline solution to allow pressure wave transmission to the transducer outside of the body, which limits continuous IAP monitoring. Methods: In this study, a novel triple balloon, air-filled TraumaGuard (TG) catheter system from Sentinel Medical Technologies (Jacksonville, FL, USA) with a unique balloon-in-balloon design was evaluated in a porcine and cadaver model of IAH via laparoscopy (IAPgold). Results: In total, 27 and 86 paired IAP measurements were performed in two pigs and one human cadaver, respectively. The mean IAPTG was 20.7 ± 10.7 mmHg compared to IAPgold of 20.3 ± 10.3 mmHg in the porcine study. In the cadaver investigation, the mean IAPTG was 15.6 ± 10.8 mmHg compared to IAPgold of 14.4 ± 10.4 mmHg. The correlation, concordance, bias, precision, limits of agreement, and percentage error were all in accordance with the WSACS (Abdominal Compartment Society) recommendations and guidelines for research. Conclusions: These findings support the use of the TG catheter for continuous IAP monitoring, providing early detection of elevated IAP, thus enabling the potential for prevention of IAH and ACS. Confirmation studies with the TraumaGuard system in critically ill patients are warranted to further validate these findings.

Supine transfer test-induced changes in cardiac index predict fluid responsiveness in patients without intra-abdominal hypertension

BACKGROUND

The reversible maneuver that mimics the fluid challenge is a widely used test for evaluating volume responsiveness. However, passive leg raising (PLR) does have certain limitations. The aim of the study is to determine whether the supine transfer test could predict fluid responsiveness in adult patients with acute circulatory failure who do not have intra-abdominal hypertension, by measuring changes in cardiac index (CI).

METHODS

Single-center, prospective clinical study in a 25-bed surgery intensive care unit at the Fudan University Shanghai Cancer Center. Thirty-four patients who presented with acute circulatory failure and were scheduled for fluid therapy. Every patient underwent supine transfer test and fluid challenge with 500 mL saline for 15-30 min. There were four sequential steps in the protocol: (1) baseline-1: a semi-recumbent position with the head of the bed raised to 45°; (2) supine transfer test: patients were transferred from the 45° semi-recumbent position to the strict supine position; (3) baseline-2: return to baseline-1 position; and (4) fluid challenge: administration of 500 mL saline for 15-30 min. Hemodynamic parameters were recorded at each step with arterial pulse contour analysis (ProAQT/Pulsioflex). A fluid responder was defined as an increase in CI ≥ 15% after fluid challenge. The receiver operating characteristic curve and gray zone were defined for CI.

RESULTS

Seventeen patients were fluid challenge. The r value of the linear correlations was 0.73 between the supine transfer test- and fluid challenge-induced relative CI changes. The relative changes in CI induced by supine transfer in predicting fluid responsiveness had an area under the receiver operating characteristic curve of 0.88 (95% confidence interval 0.72-0.97) and predicted a fluid responder with 76.5% (95% confidence interval 50.1-93.2) sensitivity and 88.2% (95% confidence interval 63.6-98.5) specificity, at a best threshold of 5.5%. Nineteen (55%) patients were in the gray zone (CI ranging from -3 and 8 L/min/m2).

CONCLUSION

The supine transfer test can potentially assist in detecting fluid responsiveness in patients with acute circulatory failure without intra-abdominal hypertension. Nevertheless, the small threshold and the 55% gray zone were noteworthy limitation.

TRIAL REGISTRATION

Predicting fluid responsiveness with supine transition test (ChiCTR2200058264). Registered 2022-04-04 and last refreshed on 2023-03-26, https://www.chictr.org.cn/showproj.html?proj=166175 .

Continuous passive paracentesis versus large-volume paracentesis in the prevention and treatment of intra-abdominal hypertension in the critically ill cirrhotic patient with ascites (COPPTRIAHL): study protocol for a randomized controlled trial

BACKGROUND

Critically ill patients with cirrhosis and ascites are at high risk for intra-abdominal hypertension (IAH) which increases mortality. Clinical guidelines recommend maintaining intra-abdominal pressure (IAP) below 16 mmHg; nonetheless, more than three quarters of critically ill patients with cirrhosis develop IAH during their first week of ICU stay. Standard-of-care intermittent large-volume paracentesis (LVP) relieves abdominal wall tension, reduces IAP, optimizes abdominal perfusion pressure, and is associated with short-term improvement in renal and pulmonary dysfunction. However, there is no evidence of the superiority of different paracentesis strategies in the prevention and treatment of IAH in critically ill patients with cirrhosis. This trial aims to compare the outcomes of continuous passive paracentesis versus LVP in the prevention and treatment of IAH in patients with cirrhosis and ascites.

METHODS

An investigator-initiated, open label, randomized controlled trial, set in a general ICU specialized in liver disease, was initiated in August 2022, with an expected duration of 36 months. Seventy patients with cirrhosis and ascites will be randomly assigned, in a 1:1 ratio, to receive one of two methods of therapeutic paracentesis. A stratified randomization method, with maximum creatinine and IAP values as strata, will homogenize patient baseline characteristics before trial group allocation, within 24 h of admission. In the control group, LVP will be performed intermittently according to clinical practice, with a maximum duration of 8 h, while, in the intervention group, continuous passive paracentesis will drain ascitic fluid for up to 7 days. The primary endpoint is serum creatinine concentration, and secondary endpoints include IAP, measured creatinine clearance, daily urine output, stage 3 acute kidney injury and multiorgan dysfunction assessed at day 7 after enrollment, as well as 28-day mortality rate and renal replacement therapy-free days, and length-of-stay. Prespecified values will be used in case of renal replacement therapy or, beforehand ICU discharge, liver transplant and death. Safety analysis will include paracentesis-related complication rate and harm. Data will be analyzed with an intention-to-treat approach.

DISCUSSION

This is the first trial to compare the impact of different therapeutic paracentesis strategies on organ dysfunction and outcomes in the prevention and treatment of IAH in critically ill patients with cirrhosis and ascites.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04322201 . Registered on 20 December 2019.

Intra-abdominal hypertension and abdominal compartment syndrome in acute pancreatitis

Intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) are underrecognized entities in patients of acute pancreatitis (AP). IAH develops in 30% to 60% and ACS in 15% to 30% of all AP patients and they are markers of severe disease with high morbidity and mortality. The detrimental effect of increased IAP has been recognized in several organ systems, including the central nervous system, cardiovascular, respiratory, renal and gastrointestinal systems. The pathophysiology of IAH/ACS development in patients with AP is multifactorial. Pathogenetic mechanisms include over-zealous fluid management, visceral edema, ileus, peripancreatic fluid collections, ascites and retroperitoneal edema. Laboratory and imaging markers are neither sensitive nor specific enough to detect IAH/ACS and intra-abdominal pressure (IAP) monitoring is vital for early diagnosis and the management of patients of AP with IAH/ACS. The treatment of IAH/ACS requires a multi-modality approach with both medical and surgical attention. Medical management consists of nasogastric/rectal decompression, prokinetics, fluid management and diuretics or hemodialysis. If conservative management is not effective, percutaneous drainage of fluid collection or ascites is necessary. Despite medical management, if IAP worsens, surgical decompression is warranted. The review discusses the relevance of IAH/ACS in patients of AP and its management.

Utility of plasma CA125 as a proxy of intra-abdominal pressure in patients with acute heart failure

AIMS

Increased intra-abdominal pressure (IAP) is now considered a potential contributor to organ damage and disease progression in acute heart failure (AHF). In this work, we aimed to determine if antigen carbohydrate 125 (CA125) is associated with IAP and to identify a cutpoint of CA125 useful for ruling out intra-abdominal hypertension (defined as IAP ≥ 12 mmHg).

METHODS AND RESULTS

We prospectively evaluated a cohort of 53 patients admitted with AHF in which IAP was measured within the first 24-h of admission. The mean age was 80 ± 8 years, 31 (58.5%) were female, and 31 (58.5%) had left ventricular ejection fraction ≥50%. The median plasma levels of NT-proBNP and CA125 were 3830 pg/mL (2417-8929) and 45.8 U/mL (29.8-114.0), respectively. The median of IAP was 15 mmHg (11-17), and 39 (73%) patients had an IAP ≥ 12 mmHg. The diagnostic performance of CA125 for identifying an IAP ≥ 12 mmHg was tested using the receiving operating characteristic (ROC) curve. The cut-off for CA125 of 17.1 U/mL showed a sensitivity of 92%, a specificity of 50%, and an area under the ROC curve of 0.71. After multivariate adjustment, CA125 remained non-linearly and positively associated with higher IAP (P-value = 0.003), explaining almost 28% of the model's variability (R2: 27.6%).

CONCLUSIONS

Patients with AHF and intra-abdominal hypertension had higher CA125 plasma levels. A baseline concentration of CA125 below 17.1 U/mL will increase the odds of identifying a subset of patients with normal IAP.

Intra-Abdominal Pressure Measurement Devices: A Technologic Analysis

PURPOSE

The purpose of this Technologic Analysis is to review devices designed to measure intra-abdominal pressure (IAP); these devices are used to detect intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS).

APPROACH

Published literature focusing on devices designed to measure IAP was reviewed, comparing the options available and outlining recommendations for appropriate use. Safety information regarding IAP measurement devices was derived from the Manufacturer and User Facility Device Experience (MAUDE) database.

CONCLUSIONS

Intra-abdominal hypertension is prevalent among critically ill patients of all ages and is linked to adverse consequences, such as abdominal compartment syndrome. The condition is often unrecognized due to the lack of overt clinical symptoms, supporting the need for devices to accurately measure IAP. Commercially available devices measure IAP indirectly, typically via the bladder or stomach. Additional research is needed to demonstrate the benefits of routine screening, further define risk factors for IAH/ACS development, and evaluate the impact of measures to reduce IAP in an effort to improve patient outcomes.

Hemodynamic Collapse Caused by Cardiac Dysfunction and Abdominal Compartment Syndrome in a Patient with Mitochondrial Disease

We herein report a case of mitochondrial disease with heart and intestinal tract involvement resulting in hemodynamic collapse. A 66-year-old woman was transferred to our hospital because of cardiogenic shock. Vasopressors were administered, and a circulatory support device was deployed. However, her hemodynamics did not improve sufficiently, and we detected abdominal compartment syndrome caused by the aggravation of chronic intestinal pseudo-obstruction as a complication. Insertion of a colorectal tube immediately decreased the intra-abdominal pressure, improving the hemodynamics. Finally, we diagnosed her with mitochondrial disease, concluding that the resulting combination of acute heart failure and abdominal compartment syndrome had aggravated the hemodynamics.

Morphological changes in salivary glands of neonatal rats after intra-abdominal hypertension

OBJECTIVE

Given the overall prevalence of elevated Intra-abdominal pressure (IAP), along with earlier detection and appropriate therapy of Intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS), a significant reduction in patient morbidity and mortality is currently achieved by modern medicine. This article assesses the long-term degree of salivary gland damage in rats depending on the severity of experimental IAH during the neonatal period.

MATERIALS AND METHODS

To simulate IAH, newborn rats, under the control of intravesical manometry, were injected into the abdominal cavity with bulking collagen filler in the amount necessary to create a given level of IAP.

RESULTS

As shown by the results obtained, rats exposed to intra-abdominal hypertension for ten days had pathological changes in their salivary glands within 120 days. The severity of sialadenitis revealed a correlation with the severity of IAH. Some rats had individual reactions expressed in relative resistance to their organs' abnormalities under hypoxia.

CONCLUSIONS

It was concluded that children with severe IAH history might need the disease prevention of the CNS, kidneys, digestive, and respiratory systems and oral diseases, particularly diseases involving the salivary glands. Future research is supposed to investigate further the IAH effect on various organs and tissues, including the dentofacial system.

Awareness and management of intra-abdominal hypertension and abdominal compartment syndrome by paediatric intensive care physicians: a national survey

INTRODUCTION

This study aimed to evaluate the current awareness and management of intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) among paediatric intensivists.

MATERIAL AND METHODS

A web-based electronic survey was sent to all physicians working in paedia-tric intensive care units (PICUs) in Saudi Arabia. The survey questions obtained information regarding awareness of ACS and IAH, recognition criteria, monitoring of intra-abdominal pressure (IAP), and experience in managing ACS.

RESULTS

A total of 79 physicians responded to the survey (response rate: 53%). Among respondents 48% were consultants. 85% of respondents were familiar with IAP/IAH/ACS. Only 35% and 10% were aware of the Abdominal Compartment Society consensus definitions for IAH and ACS in the paediatric population, respectively. Most respondents considered the cut-off for IAH to be ≥ 15 mm Hg, and approximately two-thirds thought that the cut-off for ACS was higher than the currently suggested consensus definition (10 mm Hg). More than two-thirds of respondents monitored IAP in the PICU, and it was measured almost exclusively via the bladder (96%); the majority (70%) reported that they instilled volumes well above the current recommendations. Medical management was the most frequent therapeutic approach to treat IAH/ACS, while surgical decompression was the least attempted option. Decisions to decompress the abdomen were predominantly based on the presence of organ dysfunction (74.4%).

CONCLUSIONS

This survey showed that although most responding physicians claim to be familiar with IAH and ACS, their knowledge of published consensus definitions, measurement techniques, and clinical management must be updated.

Urinary catheter monitoring of intra-abdominal pressure after major abdominal surgery, a cost-benefit analysis

OBJECTIVE

To estimate costs and benefits associated with measurement of intra-abdominal pressure (IAP).

METHODS

We built a cost-benefit analysis from the hospital facility perspective and time horizon limited to hospitalization for patients undergoing major abdominal surgery for the intervention of urinary catheter monitoring of IAP. We used real-world data estimating the likelihood of intra-abdominal hypertension (IAH), abdominal compartment syndrome (ACS), and acute kidney injury (AKI) requiring renal replacement therapy (RRT). Costs included catheter costs (estimated $200), costs of additional intensive care unit (ICU) days from IAH and ACS, and costs of CRRT. We took the preventability of IAH/ACS given early detection from a trial of non-surgical interventions in IAH. We evaluated uncertainty through probabilistic sensitivity analysis and the effect of individual model parameters on the primary outcome of cost savings through one-way sensitivity analysis.

RESULTS

In the base case, urinary catheter monitoring of IAP in the perioperative period of major abdominal surgery had 81% fewer cases of IAH of any grade, 64% fewer cases of AKI, and 96% fewer cases of ACS. Patients had 1.5 fewer ICU days attributable to IAH (intervention 1.6 days vs. control of 3.1 days) and a total average cost reduction of $10,468 (intervention $10,809, controls $21,277). In Monte Carlo simulation, 86% of 1,000 replications were cost-saving, for a mean cost savings of $10,349 (95% UCI $8,978, $11,720) attributable to real-time urinary catheter monitoring of intra-abdominal pressure. One-way factor analysis showed the pre-test probability of IAH had the largest effect on cost savings and the intervention was cost-neutral at a prevention rate as low as 2%.

CONCLUSIONS

In a cost-benefit model using real-world data, the potential average in-hospital cost savings for urinary catheter monitoring of IAP for early detection and prevention of IAH, ACS, and AKI far exceed the cost of the catheter.

Effect of continuous hemofiltration on severe acute pancreatitis with different intra-abdominal pressure: A cohort study

BACKGROUND

The clinical efficacy and timing of continuous veno-venous hemofiltration (CVVH) in the treatment of severe acute pancreatitis (SAP) remain uncertain. In this prospective cohort study, patients with SAP were classified according to intra-abdominal pressure (IAP).

METHODS

Seventy-four patients with SAP admitted to the intensive care unit were randomly divided into group A (IAP ≥20 mm Hg) and group B (with IAP ≤20 mm Hg). Then, according to whether CVVH was administered or not, groups A and B were divided into 4 subgroups: group A1 and B1 (non-CVVH treatment), group A2 and B2 (CVVH treatment). Changes in clinical and laboratory indicators were recorded before and on the seventh day after treatment, and clinical outcomes were analyzed.

RESULTS

Before treatment, there was no significant difference in general conditions between subgroups A1 and A2, and between subgroups B1 and B2. After CVVH treatment, the indicators recorded in group A2 were significantly improved compared to those in group A1 (P < .05). In group A2, the 28 day operation rate was lower (P < .05), as mechanical ventilation, gastric decompression, and intensive care unit treatment time were shorter (P < .05). However, there was no statistically significant difference in any of the above indicators between subgroups B (P > .05). Groups A2 and B2 had more days of negative fluid balance within 1 week of admission than groups A1 and B1 (P < .05).

CONCLUSIONS

For SAP, patients with IAP ≥20 mm Hg can benefit from treatment with CVVH, but for patients with IAP ≤20 mm Hg, the efficacy is not clear, and monitoring IAP may be an indicator to decide whether or when to initiate CVVH. Negative fluid balance caused by CVVH treatment may be one of the reasons for the benefit of this group of patients.

Non-Invasive Intra-Abdominal Pressure Measurement by Means of Transient Radar Method: In Vitro Validation of a Novel Radar-Based Sensor

Intra-abdominal hypertension, defined as an intra-abdominal pressure (IAP) equal to or above 12 mmHg is one of the major risk-factors for increased morbidity (organ failure) and mortality in critically ill patients. Therefore, IAP monitoring is highly recommended in intensive care unit (ICU) patients to predict development of abdominal compartment syndrome and to provide a better care for patients hospitalized in the ICU. The IAP measurement through the bladder is the actual reference standard advocated by the abdominal compartment society; however, this measurement technique is cumbersome, non-continuous, and carries a potential risk for urinary tract infections and urethral injury. Using microwave reflectometry has been proposed as one of the most promising IAP measurement alternatives. In this study, a novel radar-based method known as transient radar method (TRM) has been used to monitor the IAP in an in vitro model with an advanced abdominal wall phantom. In the second part of the study, further regression analyses have been done to calibrate the TRM system and measure the absolute value of IAP. A correlation of –0.97 with a p-value of 0.0001 was found between the IAP and the reflection response of the abdominal wall phantom. Additionally, a quadratic relation with a bias of −0.06 mmHg was found between IAP obtained from the TRM technique and the IAP values recorded by a pressure gauge. This study showed a promising future for further developing the TRM technique to use it in clinical monitoring.

Abdominal compartment syndrome in burns patients: Introduction of an evidence-based management guideline and algorithm

ABSTRACT

Abdominal compartment syndrome is a serious potential complication of burn injury, and carries high morbidity and mortality. Although there are generalised published guidelines on managing the condition, to date no management algorithm has yet been published tailored specifically to the burn injury patient. We set out to examine the literature on the subject in order to produce an evidence based management guideline, with the aim of improving outcomes for these patients. The guideline covers early detection and assessment of the condition as well as optimum medical, surgical and postoperative management. We believe that this guideline provides a much needed benchmark for managing burns patients with raised intra-abdominal pressure, as well as providing a template for further research and improvements in care.

The Correlation of Intraabdominal Pressure With Renal Resistive Index

BACKGROUND

To evaluate the correlation between intraabdominal pressure (IAP) measured via the bladder and renal resistive index (RRI) measured by Doppler ultrasonography (USG).

METHODS

Eighty consecutive surgical patients were included into this study. Before Doppler USG evaluation, IAP was measured by a Foley catheter via the bladder. The left and right RRI, the diameters of the inferior vena cava and portal vein were measured by colored Doppler USG. Spearman correlation analysis was used to evaluate the correlation between different measurements. Intraabdominal hypertension (IAH) was defined as of IAP ≥ 12 mmHg. Significantly different variables from the univariate analysis between patients with and without IAH were entered into backward stepwise binary logistic regression analysis of IAH as the dependent variable. P values < 0.05 were accepted as statistically significant.

RESULTS

In total, 80 patients were included into study. In 27 patients (34%) IAP was normal and in 53 patients (66%) IAH was diagnosed. The Spearman correlation analysis of IAP and the ultrasonographic measurements revealed a strong correlation between RRI and IAP (P < 0.001). Patients with IAH were more likely to be diabetic and had abdominal incisional hernia compared with patients with normal IAP (P < 0.05). The results of the multivariate logistic regression analysis revealed right RRI as the only independent predictor of IAH (B: 57.04, S. E.: 13.7, P < 0.001).

CONCLUSIONS

There is a strong correlation between IAP and RRI. RRI can be an alternative, noninvasive technique for the diagnosis and follow-up of IAH after further evaluations in different patient groups.

Bench Validation of a Handcrafted Prototype Catheter for Intra-gastric Pressure Monitoring

BACKGROUND

Abdominal compartment syndrome is a sustained intra-abdominal pressure (IAP) >20 mm Hg associated with new organ dysfunction. In order to prevent its development and related complications, IAP monitoring should be performed in patients with risk factors. Although techniques for its monitoring have been developed, they are of high cost and not always available in low- and lower-middle-income countries. Therefore, we aim to develop and validate in a bench model a handcrafted catheter to be used as an alternative method to measure the intra-gastric pressure (IGP) as a surrogate of the IAP.

METHODS

We used an acrylic water container as a model of the abdomen and four handcrafted catheters made of a 16 Fr Levin tube with a globe finger tied with silk in the distal end, inflated with 1 cm of air. They were placed on the bottom of the container where the water pressure was directly measured as a gold standard. The agreement between the two measures was assessed with the Bland-Altman method.

RESULTS

We performed 120 simultaneous measures. The mean pressure difference was 0.218 (95% CI 0.074 to 0.363).

CONCLUSIONS

The handcrafted prototype catheter and the direct measure were highly correlated. The new catheter is a reliable and reproducible tool for pressure monitoring. However, before it can be used in the clinical setting for IAP monitoring, validation in human models in a real clinical setting needs to be performed.

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.

Expeditious Diagnosis and Laparotomy for Patients with Acute Abdominal Compartment Syndrome May Improve Survival

Causes of abdominal compartment syndrome (ACS) are varied and can result from both medical and surgical diseases. Early recognition of ACS and prompt surgical treatment has been shown to improve mortality. We hypothesize that earlier recognition of ACS and earlier involvement by surgical specialists may improve mortality. A retrospective review between July 2010 and July 2015 was performed of adult patients who underwent decompressive laparotomy for ACS. Patients were divided into surgical and medical intensive care units (SICU and MICU) arms. Twenty patients were included (MICU = 12; SICU = 8) without significant difference between the groups. Median time from admission to suspicion for MICU patients was 60 hours versus 13 hours for SICU patients (P = 0.013). Time from suspicion to surgical consult was 60 minutes versus 0 minutes, respectively (P = 0.003), however, time from surgical consult to intervention was not different. Mortality rate in the MICU was 83 per cent versus 12.5 per cent in the SICU (P = 0.005). Patients in the SICU who developed ACS were more quickly diagnosed than those in the MICU. These patients had a shorter time from suspicion of ACS to surgical consultation and eventual surgical intervention, and was associated with improved survival. A multidisciplinary approach, including early surgical consultation, for patients in whom there is a suspicion of ACS may contribute to improved mortality.

Liver function assessment by indocyanine green plasma disappearance rate in patients with intra-abdominal hypertension after "non-hepatic" abdominal surgery

BACKGROUND AND OBJECTIVE

Liver function assessment in patients with intra-abdominal hypertension (IAH) after major abdominal surgery is complex and often confounding. Elevated intra-abdominal pressure (IAP) often occurs after major abdominal surgery, and is associated with decreased abdominal blood flow and organ dysfunction, and it could cause abdominal compartment syndrome (ACS), which is a life-threatening condition. Plasma disappearance rate (PDR) of indocyanine green (ICG) and ICG retention rate after 15 min (R15) were used to evaluate liver function and as a prognostic parameter after major abdominal surgery.

METHODS

In this prospective/observational study, 51 patients were followed in the surgical intensive care unit after major abdominal surgery (operation of the small and large intestine, stomach, pancreas, spleen, or resection of the abdominal aorta), 29 had IAH. The PDR-ICG and R15 were analyzed 24 h after surgery concurrently with IAP, APP, bilirubin, AST, ALT, prothrombin time, albumin, cardiac index, arterial lactate, oxygen delivery, MAP (mean arterial pressure), APACHE II (acute physiology and chronic health evaluation), SOFA (sequential organ failure assessment), and SAPS II (simplified acute physiology score). IAH has been defined as a peak intra-abdominal pressure (IAP) value of ≥12 mmHg, at a minimum, as two standardized measurements obtained 1-6 h apart.

RESULTS

The PDR-ICG measured 24 h after surgery was not different among groups (20.95% [SD = 10.34] vs 25.40% [SD = 7.42]), p = .094. ICG R15 was significantly higher in patients with IAH, 11.10% [SD = 13.82] vs 8.30 [SD = 11.46], p < .05, respectively. The PDR/ICG value was significantly lower in non-survivors than survivors (16.82 [SD = 10.87] vs 24.35 [SD = 8.48], p < .05).

CONCLUSIONS

The results suggest that PDR/ICG and ICG R15 are useful dynamic tests for evaluation of complex liver function and survival prediction after major abdominal surgery in patients with IAH.

Abdominal compartment syndrome and ruptured aortic aneurysm: Validation of a predictive test (SCA-AAR)

BACKGROUND

The abdominal compartment syndrome (ACS) has been clearly identified as being one of the main causes of mortality after ruptured abdominal aortic aneurysm (rAAA). The ACS is defined as a sustained intra-abdominal pressure > 20 mm Hg associated with a new organ dysfunction or failure. A pilot study was conducted and found that the threshold of 3 among 8 selected criteria, we would predict an ACS occurrence with a 54% positive predictive value and a 92% negative predictive value. But a multicentric prospective study was clearly needed to confirm these results. The outcome of this new study is to assess the qualities of a predictive test on occurrence of the ACS after rAAA surgery.

METHODS

This is a 30 months prospective cohort study conducted in 12 centers and 165 patients will be included. All patients with a rAAA will be consecutively included, whatever the surgical treatment. At the end of surgery, all patients have an abdominal closure and a monitoring of intrabladder pressure will be established every 3 to 4 hours. Decompressive laparotomy will be indicated when ACS occurs. Follow-up period is 1 month. Eight pre- and per-operative criteria will be studied: anemia, hypotension, cardiac arrest, obesity, massive fluid resuscitation, transfusion, hypothermia, and acidosis.

DISCUSSION

In the literature, there is no recommendation about prophylactic decompression, but early decompressive laparotomy appears to improve survival. This study should make it possible to establish a predictive test, detect the ACS early, and consider a prophylactic decompression in the operating room.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT02859662, Registered on 4 August 2016.

[Comparative diagnostic value of various methods of intracavitary pressure measurement in abdominal compartment syndrome]

AIM

To investigate diagnostic value of various methods of biophysical somatic parameters (BSP) monitoring in peritonitis complicated by abdominal compartment syndrome.

MATERIAL AND METHODS

220 patients with advanced peritonitis complicated by compartment syndrome were enrolled. Sensitivity, specificity, diagnostic value of the measurement of intraabdominal, intraintestinal, intrathoracic pressure, paravulnar tissues tension depending on abdominal hypertension severity were determined.

RESULTS

BSP control including intraabdominal, intraintestinal, intrathoracic pressure and paravulnar tissues tension is effective for BPS disturbances diagnosis and abele to detect them significantly more often (p=0.037) compared with M. Cheatham's method alone.

Kidney Failure Due to Abdominal Compartment Syndrome Following Snakebite

Treatment of snakebite complications is challenging, as it is difficult to distinguish what kind of antivenins should be used. Kidney failure as a result of rhabdomyolysis or hemolysis may happen due to accumulated fluids that increase the pressure in the abdomen. This case report describes acute kidney failure probably due to intra-abdominal hypertension following an unknown bite.

Diagnosis and treatment of rare complications of pelvic fractures

PURPOSE

To enhance the awareness of rare complications of pelvic fracture and describe the correct diagnosis and effective treatment.

METHODS

A total of 188 cases of pelvic fractures were retrospectively reviewed, and four patients who suffered from four types of rare pelvic fracture complications were described, namely ureteral obstruction caused by retroperitoneal hematoma-induced abdominal compartment syndrome (ACS), bowel entrapment, external iliac artery injury, and open scrotal sac injury.

RESULTS

We demonstrated that combined measures should be employed to prevent the occurrence of ACS following major pelvic fractures. Ureteral catheter support may be a good option at an early stage when ACS occurred. Contrasted computed tomography examination and sufficient awareness are keys to a correct diagnosis of bowel entrapment following pelvic fractures. Recognition of risk factors, early diagnosis, and prompt treatment of suspected injury of the external iliac artery are keys to patient survival and to avoid limb loss. Scrotal and/or testicular injury complicated by pelvic fractures should be carefully treated to maintain normal gonad function. Additionally, establishment of a sophisticated trauma care system and multi-disciplinary coordination are important for correct diagnosis and treat- ment of rare complications in pelvic fractures.

CONCLUSIONS

Rare complications of pelvic fractures are difficult to diagnose and negatively impact outcome. Recognition of risk factors and sufficient awareness are essential for correct diagnosis and prompt treatment.

[Intra-abdominal pressure as a surgery predictor in patients with acute abdominal pain]

BACKGROUND

Intra-abdominal pressure is the pressure's state of balance within the abdominal cavity when a patient is at rest. This pressure may vary during mechanical ventilation or spontaneous breathing. The objective was to establish the intra-abdominal pressure as a surgery predictor in patients with acute abdominal pain.

METHODS

From April to December, 2013, it was carried out a nested case-control study on patients with acute abdominal pain in the emergency room of a second level hospital. Thirty-seven patients fit the inclusion criteria; they all underwent surgery with a previous measurement of the intra-abdominal pressure. Based on the results of the anatomopathological study, we divided the patients into two groups: those with evidence of acute abdominal inflammatory process (n=28) (case group), and patients without evidence of acute abdominal inflammatory process (n=9) (control group).

RESULTS

In the case group, 100 % of patients shown high intra-abdominal pressure with a p=0.01 (OR=5 [95 % CI=2.578-9.699]. In the case group, the mean intra-abdominal pressure was 11.46, and in the control group 9.2 (p=0.183).

CONCLUSIONS

Abdominal pain requiring surgical intervention is directly related to intra-abdominal pressure>5 mmHg.

Intraoperative Pneumothorax Presenting as Abdominal Distention

A 74-year-old man with a history of lung cancer presented for right upper lobectomy. After induction of anesthesia, it was noted that the abdomen became progressively more distended. Soon afterward, there was a significant decrease in tidal volume. Ultrasonography of the lung showed no sign of pneumothorax at the anterior second intercostal space. However, the roentgenograms showed a massive right-sided pneumothorax and extensive pneumoperitoneum. Both the pneumothorax and the pneumoperitoneum were decompressed in the operating room, and the elective lobectomy proceeded as previously planned. The patient was extubated at the end of the operation, and there were no sequelae postoperatively.

Study on the correlation between the changes in intra-abdominal pressure and renal functional in the patients with abdominal compartment syndrome

OBJECTIVE

To observe the effect on renal function from increased intra-abdominal pressure.

PATIENTS AND METHODS

Sixty patients with abdominal compartment syndrome (ACS) were included in this study. Intra-abdominal pressure, mean arterial pressure (MAP) and central venous pressure (CVP) were recorded three times per day at a fixed time. Meanwhile, blood samples were collected for serum creatinine measurement and urine volume per hour was recorded.

RESULTS

The urine volume gradually decreased with the increasing intra-abdominal pressure, from 92. 6 ± 20 ml/h to 27.9 ± 20 ml/h (p < 0. 05), and the serum creatinine increased from 68.4 ± 39.9 mol/L to 249.4 ± 111.5 mol/L (p < 0. 05). The CVP increased from 0.98 ± 0.19 kPa to 1.56 ± 0.31 kPa with the increase or decrease of the MAP. The increase in intra-abdominal pressure was negatively related to the urine volume (r = -0.193, p < 0.05), and positively related to the serum creatinine (r = 0.162, p < 0.05), but not related to the MAP.

CONCLUSIONS

The increase of intra-abdominal pressure, was closely related to oliguria and increasing serum creatinine. The use of fluid resuscitation and diuretics had few effects on the recovery of the renal function. When the intra-abdominal pressure had decreased, the urine volume increased, and the serum creatinine decreased.

The Decrease of Peripheral Blood CD4+ T Cells Indicates Abdominal Compartment Syndrome in Severe Acute Pancreatitis

OBJECTIVE

Few data are available on the role of T lymphocytes and inflammatory cytokines in abdominal compartment syndrome (ACS) in severe acute pancreatitis (SAP). We conducted a retrospective study to assess the risk factors associated with ACS in SAP.

METHODS

A total of 76 SAP patients who were admitted within 24 hours after symptom onset in our study. There were 36 patients suffering from ACS and 40 from intra-abdominal hypertension (IAH). On the 1st, 3rd and 7th days after hospital admission, the following variables were assessed: serum value of C-reactive protein (CRP), and the proportions of peripheral CD4+ and CD8+ T lymphocytes. Acute Physiology and Chronic Health Evaluation II (APACHE II) score, and computed tomography severity index (CTSI) score were assessed on days 1 and 7 after hospitalization.

RESULTS

Compared with the patients with IAH, ACS patients showed statistically higher CRP value on 7th day after hospital admission, proportions of CD4+ T cells on days 1, 3, 7 and CD4+/CD8+ ratio on day 1 were significantly lower (P < 0.05, respectively). A CD4+ T cell proportion of 30.3% on the 1st day indicated ACS with an area under the curve (AUC) of 0.774, a sensitivity with 82.5% and specificity with 72.0%, respectively. Sensitivity/specificity for predicting ACS in SAP patients on day 1 was 70.0%/68.0% for CD4+/CD8+ ratio, 72.2%/65.0% for APACHE II score.

CONCLUSIONS

The reduction of peripheral blood CD4+ T lymphocytes is associated with ACS in SAP, and may act as a potential predictor of ACS in SAP.

Identifying patients at risk for high-grade intra-abdominal hypertension following trauma laparotomy

BACKGROUND

Abdominal Compartment Syndrome (ACS) is an uncommon but deleterious complication after trauma laparotomy. Early recognition of patients at risk of developing ACS is crucial for their outcome. The aim of this study was to compare the characteristics of patients who developed high-grade intra-abdominal hypertension (IAH) (i.e., grade III or IV; intra-abdominal pressure, IAP >20 mm Hg) following an injury-related laparotomy versus those who did not (i.e., IAP ≤20 mm Hg).

METHODS

A retrospective analysis of consecutive trauma patients admitted to a level 1 trauma centre in Australia between January 1, 1995 and January 31, 2010 was performed. A comparison was made between characteristics of patients who developed high-grade IAH following trauma laparotomy versus those who did not.

RESULTS

A total of 567 patients (median age 31 years) were included in this study. Of these patients 10.2% (58/567) developed high-grade IAH of which 51.7% (30/58) developed ACS. Patients with high-grade IAH were older (p<0.001), had a higher Injury Severity Score (p<0.001), larger base deficit (p<0.001) and lower temperature at admission (p=0.011). In the first 24h of admission, patients with high-grade IAH received larger volumes of crystalloids (p<0.001), larger volumes of colloids (p<0.001) and more units of packed red blood cells (p<0.001). Following surgery prolonged prothrombin (p<0.001) and partial thromboplastin times (p<0.001) were seen. The patients with high-grade IAH suffered higher mortality rates (25.9% (15/58) vs. 12.2% (62/509); p=0.012).

CONCLUSION

Of all patients who underwent a trauma laparotomy, 10.2% developed high-grade IAH, which increases the risk of mortality. Patients with acidosis, coagulopathy, and hypothermia were especially at risk. In these patients, the abdomen should be left open until adequate resuscitation has been achieved, allowing for definitive surgery.

LEVEL OF EVIDENCE

This is a level III retrospective study.

Intra-abdominal pressure correlates with extracellular water content

Background

Secondary increase in intra-abdominal pressure (IAP) may result from extra-abdominal pathology, such as massive fluid resuscitation, capillary leak or sepsis. All these conditions increase the extravascular water content. The aim of this study was to analyze the relationship between IAP and body water volume.

Material and Methods

Adult patients treated for sepsis or septic shock with acute kidney injury (AKI) and patients undergoing elective pharyngolaryngeal or orthopedic surgery were enrolled. IAP was measured in the urinary bladder. Total body water (TBW), extracellular water content (ECW) and volume excess (VE) were measured by whole body bioimpedance. Among critically ill patients, all parameters were analyzed over three consecutive days, and parameters were evaluated perioperatively in surgical patients.

Results

One hundred twenty patients were studied. Taken together, the correlations between IAP and VE, TBW, and ECW were measured at 408 time points. In all participants, IAP strongly correlated with ECW and VE. In critically ill patients, IAP correlated with ECW and VE. In surgical patients, IAP correlated with ECW and TBW. IAP strongly correlated with ECW and VE in the mixed population. IAP also correlated with VE in critically ill patients. ROC curve analysis showed that ECW and VE might be discriminative parameters of risk for increased IAP.

Conclusion

IAP strongly correlates with ECW.

Reliability of intra-abdominal pressure measurements using the modified Kron technique

OBJECTIVES

Assessment of intra-abdominal pressure (IAP) and the likelihood of abdominal compartment syndrome using valid and reliable measures is an important tool in the assessment of critically ill patients. The current method of relying on a single IAP per measurement period to determine patient clinical status raises the question: is a single intermittent IAP measurement an accurate indicator of clinical status or should more than one measurement be taken per measurement period?

METHODS

This study sought to assess the reliability of IAP measurements. Measurements were taken using the modified Kron technique. A total of two transvesical intra-abdominal pressure measurements were undertaken per patient using a standardized protocol. Recordings were taken at intervals of 5 minutes.

RESULTS

The majority of participants (58%) were surgical patients. Thirty-two were males and the mean age was 58 years (SD: 16·7 years). The concordance correlation coefficient between the two measurements was 0·95. Both the scatter and Bland-Altman plots demonstrate that the comparisons of two measurements are highly reproducible.

CONCLUSION

The findings of this study suggest that conducting two IAP measurements on single patient produce comparable results; therefore, there appears to be no advantage in doing two IAP measurements on a single patient. The measurement of an IAP requires the implementation of a standardized protocol and competent and credentialed assessors trained in the procedure.

Airway pressures as surrogate estimates of intra-abdominal pressure

Intra-abdominal pressure (IAP) measurements are essential to the diagnosis and management of patients with intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS). Peak inspiratory pressure (PIP), plateau pressure (Pplat), and mean airway pressure (Paw) are used by some surgeons as surrogate estimates of IAP during abdominal closure. Thirty mechanically ventilated surgical/trauma patients with risk factors for IAH/ACS underwent simultaneous triplicate measurements of PIP, Pplat, Paw, and IAP. PIP, Pplat, and Paw were compared with IAP using both coefficient of determination and Bland and Altman analysis. The coefficient of determination for each airway pressure in predicting change in IAP was: PIP 5 per cent (P = 0.24), Pplat 17 per cent (P = 0.02), and Paw 15 per cent (P = 0.03). Bland and Altman analysis identified that marked variability exists between airway pressure and IAP measurements: PIP 19.3 ± 18.7 mmHg, Pplat 11.1 ± 13.7 mmHg, and Paw 2.0 ± 9.8 mmHg. Airway pressures do not accurately reflect IAP and cannot be substituted for IAP measurements in patients at risk for IAH/ACS.

Predictors of critical acute pancreatitis: a prospective cohort study

Critical acute pancreatitis (CAP) has recently emerged as the most ominous severity category of acute pancreatitis (AP). As such there have been no studies specifically designed to evaluate predictors of CAP. In this study, we aimed to evaluate the accuracy of 4 parameters (Acute Physiology and Chronic Health Evaluation [APACHE] II score, C-reactive protein [CRP], D-dimer, and intra-abdominal pressure [IAP]) for predicting CAP early after hospital admission. During the study period, data on patients with AP were prospectively collected and D-dimer, CRP, and IAP levels were measured using standard methods at admission whereas the APACHE II score was calculated within 24 hours of hospital admission. The receiver-operating characteristic (ROC) curve analysis was applied and the likelihood ratios were calculated to evaluate the predictive accuracy. A total of 173 consecutive patients were included in the analysis and 47 (27%) of them developed CAP. The overall hospital mortality was 11% (19 of 173). APACHE II score ≥11 and IAP ≥13 mm Hg showed significantly better overall predictive accuracy than D-dimer and CRP (area under the ROC curve-0.94 and 0.92 vs. 0.815 and 0.667, correspondingly). The positive likelihood ratio of APACHE II score is excellent (9.9) but of IAP is moderate (4.2). The latter can be improved by adding CRP (5.8). In conclusion, of the parameters studied, APACHE II score and IAP are the best available predictors of CAP within 24 hours of hospital admission. Given that APACHE II score is rather cumbersome, the combination of IAP and CRP appears to be the most practical way to predict critical course of AP early after hospital admission.

Early screening to identify patients at risk of developing intra-abdominal hypertension and abdominal compartment syndrome

BACKGROUND

To develop a screening tool to identify patients at risk of developing intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) within 24 h of a patient's admission to intensive care unit (ICU).

METHODS

Prospective, observational study of 403 consecutively enrolled patients with an indwelling catheter, admitted to a mixed medical-surgical ICU in a tertiary referral, university hospital. Intra-abdominal pressure was measured at least twice daily and IAH and ACS defined as per consensus definitions.

RESULTS

Thirty-nine per cent of patients developed IAH and 2% developed ACS. Abdominal distension, hemoperitoneum/pneumoperitoneum/intra-peritoneal fluid collection, obesity, intravenous fluid received > 2.3 l, abbreviated Sequential Organ Failure Assessment score > 4 points and lactate > 1.4 mmol/l were identified as independent predictors of IAH upon admission to ICU. The presence of three or more of these risk factors at admission identified patients that would develop IAH with a sensitivity of 75% and a specificity of 76%, the development of grades II, III and IV IAH with a sensitivity of 91% and a specificity of 62%. Patients that developed IAH required a significantly longer duration of mechanical ventilation and ICU care. Patients that developed grades II-IV IAH had a significantly higher rate of ICU mortality.

CONCLUSION

IAH is a common clinical entity in the intensive care setting that is associated with morbidity and mortality. A screening tool, based on data readily available within a patient's first 24 h in ICU, was developed and effectively identified patients that required intra-abdominal pressure monitoring.

Postinjury abdominal compartment syndrome: from recognition to prevention

Postinjury abdominal compartment syndrome (ACS) is an example of a deadly clinical occurrence that was eliminated by strategic research and focused preventions. In the 1990s, the syndrome emerged with the widespread use of damage control surgery and aggressive crystalloid-based resuscitation. Patients who previously exsanguinated on the operating table made it to intensive care units, but then developed highly lethal hyperacute respiratory, renal, and cardiac failure due to increased abdominal pressure. Among many factors, delayed haemorrhage control and preload driven excessive use of crystalloid resuscitation were identified as modifiable predictors. The surrogate effect of preventive strategies, including the challenge of the 40-year-old standard of large volume crystalloid resuscitation for traumatic shock, greatly reduced cases of ACS. The discoveries were rapidly translated to civilian and military trauma surgical practices and fundamentally changed the way trauma patients are resuscitated today with substantially improved outcomes.

Embryonal natural orifice transluminal endoscopic surgery treating severe acute pancreatitis complicated by abdominal compartment syndrome

BACKGROUND/AIMS

This study aims to estimate the value of embryonal natural orifice transluminal endoscopic surgery (ENOTES) as a treatment for severe acute pancreatitis (SAP) complicated by abdominal compartment syndrome (ACS).

METHODOLOGY

The patients who were randomized into ENOTES group and surgery group underwent ENOTES and laparotomy, respectively. The Efficacy and complications of these two treatments were compared.

RESULTS

Enterocinesia was observed earlier in patients of ENOTES group than that of surgery group. Acute Physiology and Chronic Health Evaluation II (APACHE II) score of patients in ENOTES group was superior to that of surgery group on the 1st, 3rd and 5th day after treatment (P < 0.05). The cure rate was 96.87% in ENOTES group, which was statistically different from 78.12% in surgery group (P < 0.05). Significant differences in complications and mortality were observed between two groups (P < 0.01).

CONCLUSION

Compared with surgical abdominal decompression, ENOTES and flexible endoscope therapy is a more effective and minimal invasive surgery with less complications.

Intra-abdominal hypertension in postoperative cardiac surgery patients

OBJECTIVE

To investigate screening variables identifying patients at risk of developing intra-abdominal hypertension (IAH) after cardiac surgery.

DESIGN AND SETTING

Prospective observational study in a tertiary general intensive care unit.

PARTICIPANTS

One hundred and eight patients admitted to the ICU after cardiac surgery, with measurements of intraabdominal pressure (IAP).

MAIN OUTCOME MEASURES

Routinely collected clinical, physiological and biochemical variables were analysed with at least twice-daily measurements of IAP during the postoperative stay in the ICU. Variables available within 24 hours of admission to the ICU were evaluated against the incidence of IAH using logistic regression analysis to develop a set of screening criteria to identify patients at risk.

RESULTS

Fifty patients (46%) developed IAH during their stay in the ICU and were ventilated for longer, needed more vasopressors and stayed one more day in the ICU. Plasma albumin concentration, central venous pressure, minimal abdominal perfusion pressure, cardiopulmonary and aortic cross-clamp times and the presence of abdominal distension within the first 24 hours were associated with the occurrence of IAH. A logistic regression model using these variables correctly identified 85% of patients who developed IAH.

CONCLUSIONS

A set of screening criteria routinely available within the first 24 hours of admission to the ICU after cardiac surgery could correctly identify most patients at risk of IAH.

How to diagnose and treat abdominal compartment syndrome after endovascular and open repair of ruptured abdominal aortic aneurysms

Intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) are frequently encountered in patients treated for ruptured abdominal aortic aneurysms (rAAA) and carry a high morbidity and mortality risk. Despite these facts, IAH/ACS are still overlooked by many physicians, timely diagnosis is missed and treatment often inadequate. All staff involved in the treatment of rAAA should be aware of the risk factors predicting IAH/ACS, the profound implications and derangements on all organ systems, the clinical presentation, the appropriate measurement of intra-abdominal pressure to detect IAH/ACS and the current treatment options for these detrimental syndromes. This comprehensive review provides contemporary knowledge that should help to improve patient survival and long-term outcome.

[Measurement of intra-abdominal pressure with intravesical system Unometer Abdo-Pressure]

The measurement of intra-abdominal pressure (IAP) has been incorporated routinely in Critical Units in order to monitor and control those clinical situations that make us suspicious of intraabdominal hypertension (IAH). There are several methods to measure IAP [1-3]: direct measurement, a catheter inserted through suprapubic aspiration, although it is a discouraged procedure by being very invasive; and indirect measurement. In this method there are mainly three different techniques: Through femoral vein puncture: a catheter into the inferior vena cava is channeled. It is a technique being deprecated invasive, associated with venous thrombosis, retroperitoneal hematoma and infection. Through a gastric tube: impractical, requires managing large amounts of water associated with leakage through the pylorus risk. Through intravesical measurement: is the most commonly used method. The bladder catheter allows monitoring the PIA and diuresis and electrolyte control. This method has potential for infection associated with catheterization risk. Although this risk, it is considered the gold standard for the measurement of IAP. Have now been introduced to the market each measuring intravesical kits guaranteeing sterility circuit without disconnections. It is necessary to know the material and the correct procedure for measuring the PIA and how to interpret the results.

A systematic review and individual patient data meta-analysis on intra-abdominal hypertension in critically ill patients: the wake-up project. World initiative on Abdominal Hypertension Epidemiology, a Unifying Project (WAKE-Up!)

Intra-abdominal hypertension (IAH), defined as a pathologically increase in intraabdominal pressure, is commonly found in critically ill patients. While IAH has been associated with several abdominal as well as extra-abdominal conditions, few studies have examined the occurrence of IAH in relation to mortality. The aim of this paper was to evaluate the prognostic role of IAH and its risk factors at admission in critically ill patients across a wide range of settings and countries. An individual patient meta-analysis of all available data and a systematic review of published (in full or as abstract) medical databases and studies between 1996 and June 2012 were performed. The search was limited to "clinical trials" and "randomized controlled trials", "adults", using the terms "intra-abdominal pressure", "intraabdominal hypertension" combined with any of the terms "outcome" and "mortality". All together data on 2707 patients, representing 21 centers from 11 countries was obtained. Data on 1038 patients were not analysed because of the following exclusion criteria: no IAP value on admission (N.=712), absence of information on ICU outcome (N.=195), age <18 or >95 years (N.=131). Data from 1669 individual patients (19 centers from 9 countries) were analyzed in the meta-analysis. Presence of IAH was defined as a sustained increase in IAP equal to or above 12 mmHg. At admission the mean overall IAP was 9.9±5.0 mmHg, with 463 patients (27.7%) presenting IAH with a mean IAP of 16.3±3.4 mmHg. The only independent predictors for IAH were SOFA score and fluid balance on the day of admission. Five hundred thirteen patients (30.8%) died in intensive care. The independent predictors for intensive care mortality were IAH, SAPS II score, SOFA score and admission category. This systematic review and individual patient data meta-analysis shows that IAH is frequently present in critically ill patients and it is an independent predictor for mortality.

[Intra-abdominal hypertension in patients with severe acute pancreatitis]

The role of parapancreatitis in the intra-abdominal hypertension (IAH) progression in patients with severe acute pancreatitis with various forms of organs failure was studied. It was analyzed the treatment results of 63 patients with severe acute pancreatitis. The patients were divided into 4 groups: the first group (n=24) had not the signs of organs failure, the second group (n=15) - with symptoms of acute respiratory failure (ARF), the third group (n=11) - with a combination of ARF and acute cardiovascular failure (CVF) and the fourth group (n=13) - with a combination of ARF, CVF and acute renal failure. Intra-abdominal pressure (IAP) was measured at 1, 3, 5, 7- days from the beginning of the disease with calculation of the abdominal perfusion pressure and filtration gradient values. The prevalence evaluation of parapancreatitis was carried out on the basis of CT-data with bolus-dosing of the contrast agent, ultrasound, video laparoscopy as well as data obtained during operation and autopsy. It was defined that the intra-abdominal pressure (IAP) values was not significantly different and complied with intra-abdominal hypertension of the first grade in patients of the groups 1-3 at the first day. IAP was significantly higher and complied with intra-abdominal hypertension of the second grade in patients of the fourth group. IAP normalized to 5-7th days in patients of the first and the second groups. The patients of the third and the fourth groups had IAH of the second grade in the 7th day. There was reliable (p<0.01) average positive correlation (r=0.57) between the indications of IAH and the scale APACHE II. The patients with common parapancreatitis (n=39) had indications of IAP and APACHE II significantly higher than in patients with local forms of parapancreatitis (n=24; p<0.01). Common defeat of retroperitoneal fat determined persistent increase of IAP more than the presence of effusion in the abdominal cavity. In case of the first grade of IAH the mortality was 6.6%, the second grade - 37.5%, the third grade - 58.3% and the fourth grade - 80%. All died patients had a common parapancreatitis. The authors consider that the indications of IAP and APACHE II let to suppose an adverse outcome by the development of multiple organ failure in the early stages of the disease. Common parapancreatitis is the main feature of the persistent IAH (IAP increase during 5-7 days), which is an indication for early decompression operations on the abdominal wall.

[Role of intra-abdominal hypertension in the development and outcome of ovarian hyperstimulation syndrome]

OBJECTIVE

To evaluate the role of intraabdominal hypertension in the development and outcome of ovarian hyperstimulation syndrome.

MATERIAL AND METHODS

60 patients with varying degrees of ovarian hyperstimulation syndrome (OHSS) due to ongoing pregnancy were involved in the study. Intraabdominal pressure (IAP) was measured in the bladder. Performance of abdominal perfusion pressure, filtration gradient, extensibility and compliance of the anterior abdominal wall were evaluated. A size of the ovaries, chorionic condition and ascites were determined by ultrasonic method. Relation of pregnancy outcome and IAP was analyzed.

RESULTS

The mean value of IAP in patients with light form of ovarian hyperstimulation syndrome was 7.05 +/- 1.76 mm Hg, 13.65 +/- 1.92 mm Hg in patients with moderate form, and 20.60 +/- 2.52 mm Hg in patients with severe form of OHSS. The leading factors in the development and progression of intraabdominal hypertension (IAH) are the volume of the ovaries, ascites, and extensibility of the abdominal wall. The comparison of pregnancy outcome and severity of IAP revealed a strong positive correlation--r = 0.726, p < 0.001.

CONCLUSION

Evaluation of the severity of intra-abdominal hypertension in patients with ovarian hyperstimulation syndrome with considering the clinical data and results of laboratory and instrumental studies allow clarifying the severity of condition and predict the potential complications and pregnancy outcomes.