Computed tomography features predictive of intra-abdominal hypertension in acute necrotizing pancreatitis: A prospective study

Intra-abdominal Hypertension Is a Strong Predictor of Mortality and Poor Clinical Outcome in Severe Acute Pancreatitis

BACKGROUND

Acute pancreatitis is one of the leading causes of mortality and morbidity. Most acute pancreatitis scoring systems have no pathophysiologic basis when evaluating severity. Such a limitation led to an interest in measuring intra-abdominal pressure (IAP) as a method to predict outcomes in patients with acute pancreatitis.

AIMS

Investigate the predictive impact of intra-abdominal hypertension (IAH) on mortality and clinical outcomes in a patient hospitalized with severe acute pancreatitis.

METHODS

We conducted a systematic search of the PubMed, Embase, and Cochrane databases from inception through November 2021 for studies evaluating the effect of IAH on acute pancreatitis. Relevant data were extracted and analyzed using STATA 17 software. A random-effects model was used for all variables. Publication bias was assessed using Egger's test.

RESULTS

Fourteen studies investigating 1197 patients were included. Mortality, multiorgan dysfunction syndrome, pancreatic necrosis, renal, respiratory, and cardiovascular failure were more likely in the IAH group. However, infected necrosis and surgical intervention were not statistically significant between the two groups. After excluding abdominal compartment syndrome patients, mortality and respiratory failure were the only outcomes, which remained statistically significant.

CONCLUSIONS

Patients admitted to the hospital with severe acute pancreatitis have higher odds for mortality, multiorgan dysfunction syndrome, renal, respiratory, and cardiovascular failure if they developed IAH. IAH remained a strong predictor of mortality and respiratory failure even in the absence of abdominal compartment syndrome. Therefore, the development of IAH is a strong predictor of mortality and poor clinical outcome in such a population.

Abdominal compartment syndrome: what radiologist needs to know

The intra-abdominal hypertension (IAH) and the abdominal compartment syndrome (ACS) are life-threatening conditions with a significant rate of mortality; therefore, early detection is paramount in their optimal management. IAH is diagnosed when the intra-abdominal pressure (IAP) is more than 12 mmHg. It can occur when the intra-abdominal volume increases (ileus, ascites, trauma, pancreatitis, etc.) and/or the abdominal wall compliance decreases. IAH can cause decreased venous flow, low cardiac output, renal impairment, and decreased respiratory compliance. Consequently, these complications can lead to multiple organ failure and induce the abdominal compartment syndrome (ACS) when IAP rises above 20 mmHg. The diagnosis is usually made with intravesical pressure measurement. However, this measurement was not always possible to obtain; therefore, alternative diagnostic techniques should be considered. In this setting, computed tomography (CT) may play a crucial role, allowing the detection and characterization of pathological conditions that may lead to IAH. This review is focused on the pathogenesis, clinical features, and radiological findings of ACS, because their presence allows radiologists to raise the suspicion of IAH/ACS in critically ill patients, guiding the most appropriate treatment.

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.

Evaluation of Intra-Abdominal Hypertension Parameters in Patients with Acute Pancreatitis

BACKGROUND

Patients with acute pancreatitis develop numerous complications and organ damage due to increased intra-abdominal pressure (IAP). These extrapancreatic complications determine the clinical outcome of the disease.

MATERIALS AND METHODS

A total of 100 patients with acute pancreatitis were included in the prospective cohort study. Observed patients were divided into two groups according to their mean values of IAP (normal IAP values and elevated IAP values), which were compared with examined variables. Patients with intra-abdominal hypertension (IAH) were divided into four groups by IAP values, and those groups of patients were also compared with the examined variables.

RESULTS

Differences between body mass index (BMI) (p = 0.001), lactates (p = 0.006), and the Sequential Organ Failure Assessment (SOFA) score (p = 0.001) were statistically significant within all examined IAH groups. Differences between the mean arterial pressure (MAP) (p = 0.012) and filtration gradient (FG) (p < 0.001) were statistically significant between the first and second IAH groups in relation to the fourth. Differences in diuresis per hour (p = 0.022) showed statistical significance in relation to the first and third groups of IAH patients.

CONCLUSIONS

Changes in IAP values lead to changes in basic vital parameters MAP, APP, FG, diuresis per hour, and lactate levels in patients with acute pancreatitis. Early recognition of changes in the SOFA score accompanying an increase in the IAP value is essential.

A novel clinical prediction model of severity based on red cell distribution width, neutrophil-lymphocyte ratio and intra-abdominal pressure in acute pancreatitis in pregnancy

BACKGROUND

Acute pancreatitis in pregnancy (APIP) with a high risk of death is extremely harmful to mother and fetus. There are few models specifically designed to assess the severity of APIP. Our study aimed to establish a clinical model for early prediction of severity of APIP.

METHODS

A retrospective study in a total of 188 patients with APIP was enrolled. The hematological indicators, IAP (intra-abdominal pressure) and clinical data were obtained for statistical analysis and prediction model construction.

RESULTS

According to univariate and multivariate logistic regression analysis, we found that red cell distribution width (RDW), neutrophil-lymphocyte ratio (NLR) and Intra-abdominal pressure (IAP) are prediction indexes of the severity in APIP (p-value < 0.05). Our novel clinical prediction model was created by based on the above three risk factors and showed superior predictive power in primary cohort (AUC = 0.895) and validation cohort (AUC = 0.863). A nomogram for severe acute pancreatitis in pregnancy (SAPIP) was created based on the three indicators. The nomogram was well-calibrated.

CONCLUSION

RDW, NLR and IAP were the independent risk factors of APIP. Our clinical prediction model of severity in APIP based on RDW, NLR and IAP with predictive evaluation is accurate and effective.

Evaluation of Inflammatory Infiltration in the Retroperitoneal Space of Acute Pancreatitis Using Computer Tomography and Its Correlation with Clinical Severity

This paper investigates the correlation between the degree and severity of CT inflammatory infiltration in the retroperitoneal space of acute pancreatitis (AP). A total of 113 patients were included based on diagnostic criteria. The general data of the patients and the relationship between the computed tomography severity index (CTSI) and pleural effusion (PE), involvement, degree of inflammatory infiltration of retroperitoneal space (RPS), number of peripancreatic effusion sites, and degree of pancreatic necrosis on contrast-enhanced CT at different times were studied. The results showed that the mean age of onset in females was later than that in males; 62 cases involved RPS to varying degrees, with a positive rate of 54.9% (62/113), and the total involvement rates of only the anterior pararenal space (APS); both APS and perirenal space (PS); and APS, PS, and posterior pararenal space (PPS) were 46.9% (53/113), 53.1% (60/113), and 17.7% (20/113), respectively. The degree of inflammatory infiltration in the RPS worsened with the increase in CTSI score; the incidence of PE was higher in the group greater than 48 hours than in the group less than 48 hours; necrosis >50% grade was predominant (43.2%) 5 to 6 days after onset, with a higher detection rate than other time periods (P < 0.05). Thus, when the PPS was involved, the patient's condition can be treated as severe acute pancreatitis (SAP); the higher the degree of inflammatory infiltration in the retroperitoneum, the higher the severity of AP. Enhanced CT examination 5 to 6 days after onset in patients with AP revealed the greatest extent of pancreatic necrosis.

Abdominal Compartment Syndrome in Acute Pancreatitis: A Narrative Review

Abdominal compartment syndrome (ACS) represents a severe complication of acute pancreatitis (AP), resulting from an acute and sustained increase in abdominal pressure >20 mmHg, in association with new organ dysfunction. The harmful effect of high intra-abdominal pressure on regional and global perfusion results in significant multiple organ failure and is associated with increased morbidity and mortality. There are several deleterious consequences of elevated intra-abdominal pressure on end-organ function, including respiratory, cardiovascular, gastrointestinal, neurologic, and renal effects. It is estimated that about 15% of patients with severe AP develop intra-abdominal hypertension or ACS, with a mortality rate around 50%. The treatment of abdominal compartment syndrome in acute pancreatitis begins with medical intervention and percutaneous drainage, where possible. Abdominal compartment syndrome unresponsive to conservatory treatment requires immediate surgical decompression, along with vacuum-assisted closure therapy techniques, followed by early abdominal fascia closure.

Intra-abdominal hypertension and abdominal compartment syndrome

PURPOSE OF REVIEW

Intra-abdominal hypertension (IAH) has been acknowledged as an important contributor to organ dysfunction in critically ill patients, both in surgical and medical conditions. As our understanding of the pathophysiology evolves, risk factors are better recognized, preventive measures can now be implemented and therapeutic interventions tailored to the physiology of the patient. In the current review, we want to highlight developing insights in the epidemiology and treatment of patients with IAH and ACS.

RECENT FINDINGS

The impact of IAH and ACS on kidney function and other outcomes continues to draw attention in recent studies. New methods for IAP measurement are under development, and the search for biomarkers to detect IAH or ACS continues. In conditions wherein IAH and ACS are common, recent studies allow better prevention and treatment of these conditions, based on the contemporary ICU management consisting of IAP measurement, judicious fluid resuscitation and decompressive laparotomy where necessary. Surgical treatment options including open abdomen therapy continue to be improved with demonstrable impact on outcomes.

SUMMARY

In this manuscript, we provide an overview of recent insights and developments in the epidemiology, monitoring and treatment of patients with IAH and/or ACS.

Intra-Abdominal Hypertension: A Systemic Complication of Severe Acute Pancreatitis

Patients with severe acute pancreatitis (SAP) present complications and organ failure, which require treatment in critical care units. These extrapancreatic complications determine the clinical outcome of the disease. Intra-abdominal hypertension (IAH) deteriorates the prognosis of SAP. In this paper, relevant recent literature was reviewed, as well as the authors’ own experiences, concerning the clinical importance of IAH and its treatment in SAP. The principal observations confirmed that IAH is a frequent consequence of SAP but is practically absent in mild disease. Common manifestations of AP such as pain, abdominal distension, and paralytic ileus contribute to increased abdominal pressure, as well as fluid loss in third space and aggressive fluid replacement therapy. A severe increase in IAP can evolve to abdominal compartment syndrome and new onset organ failure. Conservative measures are useful, but invasive interventions are necessary in several cases. Percutaneous drainage of major collections is preferred when possible, but open decompressive laparotomy is the final possibility in some cases in order to definitively reduce abdominal pressure. Intra-abdominal pressure should be measured in all SAP cases that worsen despite adequate treatment in critical care units. Conservative measures must be introduced to treat IAH, including negative fluid balance, digestive decompression by gastric–rectal tube, and prokinetics, including neostigmine. In the case of insufficient responses to these measures, minimally invasive interventions should be preferred.