Review article: the abdominal compartment syndrome

Hemodynamic pathways of gestational hypertension and preeclampsia

Gestational hypertension and preeclampsia are the 2 main types of hypertensive disorders in pregnancy. Noninvasive maternal cardiovascular function assessment, which helps obtain information from all the components of circulation, has shown that venous hemodynamic dysfunction is a feature of preeclampsia but not of gestational hypertension. Venous congestion is a known cause of organ dysfunction, but its potential role in the pathophysiology of preeclampsia is currently poorly investigated. Body water volume expansion occurs in both gestational hypertension and preeclampsia, and this is associated with the common feature of new-onset hypertension after 20 weeks of gestation. Blood pressure, by definition, is the product of intravascular volume load and vascular resistance (Ohm's law). Fundamentally, hypertension may present as a spectrum of cardiovascular states varying between 2 extremes: one with a predominance of raised cardiac output and the other with a predominance of increased total peripheral resistance. In clinical practice, however, this bipolar nature of hypertension is rarely considered, despite the important implications for screening, prevention, management, and monitoring of disease. This review summarizes the evidence of type-specific hemodynamic profiles in the latent and clinical stages of hypertensive disorders in pregnancy. Gestational volume expansion superimposed on an early gestational closed circulatory circuit in a pressure- or volume-overloaded condition predisposes a patient to the gradual deterioration of overall circulatory function, finally presenting as gestational hypertension or preeclampsia-the latter when venous dysfunction is involved. The eventual phenotype of hypertensive disorder is already predictable from early gestation onward, on the condition of including information from all the major components of circulation into the maternal cardiovascular assessment: the heart, central and peripheral arteries, conductive and capacitance veins, and body water content. The relevance of this approach, outlined in this review, openly invites for more in-depth research into the fundamental hemodynamics of gestational hypertensive disorders, not only from the perspective of the physiologist or the scientist, but also in assistance of clinicians toward understanding and managing effectively these severe complications of pregnancy.

The prevalence, incidence and mortality associated with intra-abdominal hypertension among patients in intensive care units of a low-income country: a cohort study

Background: Intra-abdominal hypertension (IAH) is sustained increase in intra-abdominal pressure (IAP) ≥12 mmHg in adults and ≥10 mmHg in children. IAH has been noted to be associated with increased morbidity and mortality among critically ill patients. Measurement of IAP is common among at risk patients in the developed world. However, it has not received due attention in the majority of intensive care units (ICUs) in low-income countries, Uganda being one of these. This is evidenced by paucity of data and lack of protocols from the Ugandan Ministry of Health. This multi-center study was thus conducted to assess the prevalence, incidence and mortality associated with IAH among patients admitted to Ugandan ICUs.Methods:A multi-center prospective cohort study was conducted from September 2017 to February 2018 at three ICUs in Uganda. We consecutively enrolled 126 patients into the study. IAP was measured using the Harrahil manometer technique. Categorical variables were analyzed using the Chi square test and continuous variables analyzed using the t-test and Man Whitney test. The prevalence and incidence were determined using proportions and mortality was determined using survival analysis.Results:The median age was 33 years (26-48.5) for the patients without IAH and 42 years (29-55) for those with IAH. The majority of the patients were male and 9.6% of the patients were below 18 years. The prevalence of IAH was 62.7 (CI 54.1-71.3), whereas the 24 hour and 72 hour incidence of IAH was 9.3% (CI 1.3-17.2) and 14.3 % (CI 4.1-24.4), respectively.  Mortality was higher in patients with IAH compared to those without (p-value 0.003 and 0.028, mean and maximum IAP, respectively). Conclusion:We found a high prevalence and incidence of IAH among critically ill patients, associated with a high mortality. Routine screening for IAH can preempt management strategies to mitigate this.

A Case of Hepatorenal Syndrome and Abdominal Compartment Syndrome with High Renal Congestion

BACKGROUND Hepatorenal syndrome (HRS) is a reversible renal impairment that occurs in patients with acute liver failure and advanced liver cirrhosis. HRS is due to a renal vasoconstriction that results from extreme vasodilatation. It is therefore a functional disorder, not associated with structural kidney damage. On the other hand, end-stage liver diseases are often complicated by massive ascites. Massive ascites may cause abdominal compartment syndrome (ACS), which includes impairment of renal blood flow, but there are no reports indicating that kidney lesions caused by ACS may pathologically contribute to end-stage liver diseases. CASE REPORT A 40-year-old man with acute liver failure was admitted to our hospital. He was diagnosed with type 1 HRS and showed ACS at the same time. He died 30 days after admission. There were signs of congestion in the kidneys upon dissection and advanced erythroid fullness in the renal tubules. CONCLUSIONS We report an autopsy case with HRS and ACS diagnosed with a clinical and histopathological consideration of liver and kidney. Further clinical studies are needed to improve management of renal failure in patients with acute liver failure and advanced liver cirrhosis.

Liver injury in malignant ascites-induced abdominal compartment syndrome

Liver injury in malignant ascites-induced abdominal compartment syndrome (MAACS) has received little attention. In recent years, due to the gradual clarification of pathogenesis and pathological physiology of abdominal interval syndrome, liver injury in MAACS has become a hot research topic. In this paper, we will review the pathophysiological process, pathological changes, and treatment of liver injury in MAACS.

A novel nonoperative approach to abdominal compartment syndrome after abdominal wall reconstruction

INTRODUCTION

Intraabdominal hypertension and abdominal compartment syndrome have been increasingly recognized as significant causes of morbidity and mortality in both medical and surgical patients. The gold standard remains surgical intervention; however, nonoperative approaches have been investigated less. Here, we describe the successful treatment of a severe acute case by intubation, nasogastric decompression, and paralysis--a novel approach not previously described in the literature.

CASE DESCRIPTION

After the patient underwent laparoscopic bilateral component separation and repair of a large recurrent ventral hernia with a 20 30-cm Strattice mesh (LifeCell Corp, Branchburg, NJ), acute renal failure developed within 12 hours postoperatively, and was associated with oliguria, hyperkalemia, and elevated peak airway and bladder pressures. The patient was treated nonoperatively with intubation, nasogastric tube decompression, and paralysis with a vecuronium drip. Rapid reversal was seen, avoiding further surgery. Within 2 hours after intubation and paralysis, our patient's urine output improved dramatically with an initial diuresis of approximately 1 L, his bladder pressures decreased, and within 12 hours his creatinine level had normalized.

DISCUSSION

Although surgical intervention has traditionally been thought of as the most effective--and thus the gold standard--for abdominal compartment syndrome, this preliminary experience demonstrates nonoperative management as highly efficacious, with the added benefit of decreased morbidity. Therefore, nonoperative management could be considered first-line therapy, with laparotomy reserved for refractory cases only. This suggests a more complex pathology than the traditional teaching of congestion and edema alone.

Measurement of intra-abdominal pressure in dogs and cats

OBJECTIVE

To review and summarize the human and veterinary literature on intra-abdominal pressure measurement techniques.

DATA SOURCES

Human and veterinary clinical studies, research articles, reviews, and textbooks with no date restrictions with a focus on techniques for intra-abdominal pressure (IAP) measurement and their limitations.

HUMAN DATA SYNTHESIS

Human literature has established the intravesicular method as the gold standard for indirect measurement of IAP. However, current research has explored the intragastric method as a valid alternative. Recently, debate has focused on the shortcomings of the various measurement methods.

VETERINARY DATA SYNTHESIS

Early human literature using dogs as models contributed to the original data for IAP measurements in small animals. Since that time, a number of clinical studies and 1 case report have contributed to that original information. A reference interval for IAP measured by the intravesicular method has recently been determined in healthy cats.

CONCLUSIONS

Further studies investigating IAP in critically ill veterinary patients are required to establish the optimal technique for this measurement in veterinary medicine.

Intra-abdominal hypertension in the current era of modern trauma resuscitation

BACKGROUND

This study aimed to determine the incidence and outcome of post-traumatic (PT) intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) after the advances in haemostatic resuscitation.

METHODS

This is a prospective cohort study from January 2009-December 2011 involving patients with PT haemorrhagic shock. Patients' demographics, fluid resuscitation (<24 h) and damage control laparotomy (DCL), morbidity and mortality were assessed. Patients were divided into group 1 (no DCL) and group 2 (DCL needed). Further, group 1 was subdivided into three subgroups (IA pressure (IAP) <12, 12-20 and >20 mmHg).

RESULTS

One hundred seventeen patients enrolled in the study (102 in group 1 and 15 in group 2) with a mean age of 35 ± 14, injury severity score (ISS) of 23 ± 10, base deficit of -8.7 ± 2.7 mmol/L, serum lactate of 4.6 ± 2.5 mg/dL and haemoglobin level of 8.8 ± 2. Patients received 7 ± 5 red blood cell units, 6 ± 4.7 fresh frozen plasma units and 8.3 ± 3 L of crystalloid per 24 h. There were significant difference between the two groups regarding crystalloid volume, blood transfusion, base deficit and intensive care unit length of stay. However, mortality was higher in group 2 (20% versus 6%). IAP ≥ 20 mmHg was reported in 16.7% patients, while 25.5% had IAP < 12 and 57.8% had IAP of 12-20 mmHg. Patients with IAP > 20 had worse metabolic acidosis and received more blood compared with other groups. One patient died because of ACS (0.9%). Overall multiorgan failure and mortality were 5 and 7.7%, respectively.

CONCLUSION

With current practice of minimal fluid resuscitation and liberal use of damage control strategies among trauma patients, the IAH was common transient phenomena but the incidence of ACS is remarkably low.

[Abdominal compartment syndrome in severe acute pancreatitis -- literature review]

The incidence of intraabdominal hypertension or abdominal compartment syndrome, as the more severe form is called, is relatively high in patients with severe acute pancreatitis, and therefore more attention is needed to the topic. If conservative treatment fails, immediate surgical decompression is indicated. The most commonly used operation is a full thickness median laparotomy, but a transversal laparotomy may also be effective. Although subcutaneous linea alba, or bilateral anterior rectus fasciotomy is safe and effective, decompressive laparotomy is indicated in failure of these methods. The open abdomen therapy is not advised due to high morbidity. Primary closure of the abdomen is preferable.

Open versus closed abdomen treatment on liver function in rats with sepsis and abdominal compartment syndrome

BACKGROUND

Despite recent advances in understanding the mechanisms of sepsis and abdominal compartment syndrome (ACS) and of improvements in their management, the mortality rates from these conditions remain high. Few studies have compared liver injuries in patients undergoing open and closed abdomen treatment. The aim of this study was to compare the effects of open versus conservative abdominal closure approaches upon liver function using a controlled and randomized model of intra-abdominal hypertension and sepsis in a rat model.

METHODS

Healthy Sprague-Dawley rats underwent cecal ligation and puncture to induce sepsis, followed by intraperitoneal injection of air to induce intra-abdominal hypertension. Twenty-four hours later, the rats were randomly divided into two groups, one (n = 36) undergoing abdominal closure and the other (n = 36) undergoing open abdomen. Rats were killed after 1 hour, 6 hours, 1 day, 3 days, 5 days, and 7 days. Liver injury was evaluated by Hepatic Injury Severity Scoring. The levels of expression of Toll-like receptor 4 (TLR4), tumor necrosis factor-α, interleukin-6, signaling transducer and activator of transcription 3 mRNA, and suppressor of cytokine signaling 3 mRNA were assayed by reverse transcription-polymerase chain reaction.

RESULTS

The levels of tumor necrosis factor-α, interleukin-6, and signaling transducer and activator of transcription 3 mRNA were higher, and those of TLR4 and suppressor of cytokine signaling 3 mRNA were lower, in the open than in the closed group (p < 0.05 each). Serum concentrations of aspartate aminotransferase and alanine aminotransferase were also lower in the open group (p < 0.05 each).

CONCLUSIONS

Open abdominal management may improve liver regeneration soon after surgery, as well as reducing inflammatory responses, by reducing TLR4 expression.

Abdominal compartment syndrome - Intra-abdominal hypertension: Defining, diagnosing, and managing

Abdominal compartment syndrome (ACS) and intra-abdominal hypertension (IAH) are increasingly recognized as potential complications in intensive care unit (ICU) patients. ACS and IAH affect all body systems, most notably the cardiac, respiratory, renal, and neurologic systems. ACS/IAH affects blood flow to various organs and plays a significant role in the prognosis of the patients. Recognition of ACS/IAH, its risk factors and clinical signs can reduce the morbidity and mortality associated. Moreover, knowledge of the pathophysiology may help rationalize the therapeutic approach. We start this article with a brief historic review on ACS/IAH. Then, we present the definitions concerning parameters necessary in understanding ACS/IAH. Finally, pathophysiology aspects of both phenomena are presented, prior to exploring the various facets of ACS/IAH management.

Acute compartment syndrome--a life and limb threatening surgical emergency

Acute compartment syndrome is a life and limb threatening condition. Clinical assessment is the diagnostic cornerstone of compartment syndrome but pressure monitoring also has a role in equivocal cases, in unconscious or uncooperative patients, and in patients with nerve blocks and other forms of regional and epidural anesthesia. A high degree of suspicion and early decompression of all compartments at risk are important for a satisfactory outcome.

Effect of elevated intra-abdominal pressure and 100% oxygen on superior mesenteric artery blood flow and enterocyte turnover in a rat

PURPOSE

Elevated intra-abdominal pressure (IAP) has been shown to reduce mesenteric blood flow and cause intestinal damage. The purpose of the present study was to evaluate the effects of IAP and hyperoxia on superior mesenteric artery (SMA) blood flow, enterocyte proliferation and apoptosis in a rat model of abdominal compartment syndrome (ACS).

METHODS

Male rats underwent midline laparotomy. SMA was isolated and ultrasonic blood flow probes were placed on the vessel for continuous measurement of regional blood flow. Two catheters were introduced into the peritoneal cavity for inflation of air and for measurement of IAP. Rats were divided into three experimental groups: (1) Sham rats were subjected to IAP of 0 mmHg, (2) ACS-air rats were subjected to IAP of 6 mmHg for 2 h and were ventilated with air, and (3) ACS-O(2) rats were subjected to IAP of 6 mmHg and were ventilated with 100% oxygen (O(2)) during the operation and for 6 h after the operation. Intestinal structural changes, enterocyte proliferation and enterocyte apoptosis were evaluated at 24 h after operation. A paired Student's t test and the non-parametric Kruskal-Wallis ANOVA test were used as indicated. P < 0.05 was considered statistically significant.

RESULTS

IAP at 6 mmHg caused a moderate decrease in SMA blood flow. Inhalation of 100% oxygen resulted in a trend toward an increase in SMA flow when compared to air-ventilated animals. ACS rats demonstrated a significantly lower index of proliferation in jejunum and ileum as well as a significantly greater apoptotic index in jejunum compared to sham animals. Exposure to 100% oxygen resulted in a significant increase in cell proliferation in jejunum and ileum as well as in a significant decrease in cell apoptosis in jejunum compared to air-breathing animals.

CONCLUSIONS

In a rat model of ACS, elevated IAP decreases SMA blood flow and inhibits enterocyte turnover. Hyperoxia results in a trend toward an increase in SMA blood flow, increases enterocyte proliferation and inhibits cell death via apoptosis. These findings may have significant implications for ventilation strategies during laparoscopy.