Abdominal compartment syndrome in children.

Abdominal compartment syndrome is defined as sustained intra-abdominal pressure greater than 20 mm Hg (with or without abdominal perfusion pressure <60 mm Hg) associated with new organ failure or dysfunction. The syndrome is associated with 90% to 100% mortality if not recognized and treated in a timely manner. Nurses are responsible for accurately measuring intra-abdominal pressure in children with abdominal compartment syndrome and for alerting physicians about important changes. This article provides relevant definitions, outlines risk factors for abdominal compartment syndrome developing in children, and discusses an instructive case involving an adolescent with abdominal compartment syndrome. Techniques for measuring intra-abdominal pressure, normal ranges, and the importance of monitoring in the critical care setting for timely identification of intra-abdominal hypertension and abdominal compartment syndrome also are discussed.

Pediatric critical care nurses' experience with abdominal compartment syndrome.

BACKGROUND: Abdominal compartment syndrome (ACS) is a syndrome associated with multi-system effects of elevated intra-abdominal pressure (IAP) in critically ill children. It has a 90-100% mortality rate if not recognized and treated promptly. Measuring IAP helps identify patients developing intra-abdominal hypertension (IAH) which allows for timely intervention before progression to ACS. IAP helps identify ACS and guides its medical and surgical management. IAP is often measured by the bedside nurse in the intensive care unit. Pediatric critical care nurses (PCCN) play a key role in managing critically ill patients and recognizing potential causes for clinical deterioration such as ACS therefore should be knowledgeable about this entity. OBJECTIVE: The aim of this study was to assess the awareness and current knowledge of ACS among PCCN. METHODS: A ten-item written questionnaire was distributed at a National Critical Care Conference in 2006 and again in 2010. Participants of the conference voluntarily completed and immediately returned the survey. Results from the two questionnaires were compared. RESULTS: Sixty-two percent of 691 questionnaires were completed. The awareness of ACS improved from 69.3% in 2006 to 87.8% in 2010 (p < 0.001) among PCCN. "Years in practice" influenced awareness of ACS. Nurses working for 5-10 and > 10 years were, respectively, 2.34 and 1.89 times more likely to be aware of ACS than those working for < 5 years. Hands-on experience managing a child with ACS by PCCN also improved from 49.1% to 67.9% (p < 0.001) but remains low. The number of participants who never measured IAP fell from 27.3% to 19.1% (p = 0.101). The most common method being used to measure IAP is the bladder method. Knowledge of the definition of ACS remains poor with only 13.2% associating the definition of ACS with organ dysfunction in 2010 which was even lower than in 2006. CONCLUSIONS: There is increasing awareness of ACS and experience in its management among PCCN. However, few PCCN correctly understand the definition of ACS. Since recognition of IAH and early intervention can reduce morbidity and mortality in critically ill patients, further educational efforts should be directed toward improving the knowledge and recognition of ACS by PCCN.

Abdominal decompression in children.

Abdominal compartment syndrome (ACS) increases the risk for mortality in critically ill children. It occurs in association with a wide variety of medical and surgical diagnoses. Management of ACS involves recognizing the development of intra-abdominal hypertension (IAH) by intra-abdominal pressure (IAP) monitoring, treating the underlying cause, and preventing progression to ACS by lowering IAP. When ACS is already present, supporting dysfunctional organs and decreasing IAP to prevent new organ involvement become an additional focus of therapy. Medical management strategies to achieve these goals should be employed but when medical management fails, timely abdominal decompression is essential to reduce the risk of mortality. A literature review was performed to understand the role and outcomes of abdominal decompression among children with ACS. Abdominal decompression appears to have a positive effect on patient survival. However, prospective randomized studies are needed to fully understand the indications and impact of these therapies on survival in children.

Abdominal compartment syndrome: focus on the children.

This article is a concise summary of intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) with an emphasis on factors relevant to their occurrence in children. It discusses the limitations in the direct application of the current World Society of Abdominal Compartment Syndrome consensus definitions and extrapolation of management practices derived from studying adult patients to the pediatric age group. Techniques that may be used for measuring intra-abdominal pressure (IAP) in children, normal IAP ranges, risk factors for developing ACS as well as current medical and surgical management options in children are discussed.

Understanding of Abdominal Compartment Syndrome among Pediatric Healthcare Providers.

Background. The sparse reporting of abdominal compartment syndrome (ACS) in the pediatric literature may reflect inadequate awareness and recognition among pediatric healthcare providers (HCP). Purpose. To assess awareness of ACS, knowledge of the definition and intraabdominal pressure (IAP) measurement techniques used among pediatric HCP. Method. A written survey distributed at two pediatric critical care conferences. Results. Forty-seven percent of 1107 questionnaires were completed. Participants included pediatric intensivists, pediatric nurses, and others. Seventy-seven percent (n = 513) of participants had heard of ACS. Only 46.8% defined ACS correctly. The threshold IAP value used to define ACS was variable among participants. About one-quarter of participants (83/343), had never measured IAP. Conclusion. Twenty-three percent of HCP surveyed were unaware of ACS. Criteria used to define ACS were variable. Focused education on recognition of ACS and measuring IAP should be promoted among pediatric HCP.

What is the normal intra-abdominal pressure in critically ill children and how should we measure it?

INTRODUCTION: The intravesical method has been validated and is considered the gold standard for indirect intra-abdominal pressure (IAP) measurements. In adults, a standard volume (25 mL) is instilled into the bladder to measure IAP. However, the optimal volume for accurate IAP measurements in children has not been well studied and using inappropriate volumes could give erroneous IAP readings. OBJECTIVE: To determine the normal IAP in critically ill children and the optimal volume for IAP measurement by the intravesical method in this population. DESIGN: Prospective observational study. SETTING: Tertiary pediatric intensive care unit. PATIENTS: Ninety-six mechanically ventilated children younger than 18 yrs of age with no clinical evidence of intra-abdominal hypertension. MEASUREMENTS AND RESULTS: Graduated volumes of normal saline in increments of 3-50 mL were instilled in the bladder via a urethral catheter. IAP was recorded by using the AbViser device (WolfeTory Medical, Inc., Salt Lake City, UT) with each instillation. A pressure-volume curve was generated for every patient, and the minimum and mean optimal volumes were determined from this curve. Data were analyzed by stratification of patients according to weights 0-10 kg, >10-20 kg, and >20-50 kg. Descriptive statistics was used for statistical analysis. Normal IAP for critically ill children was 7 +/- 3 and was similar in the different weight groups (p = .745). Although the mean optimal volume to measure accurate IAP was variable in the different weight groups, the minimum optimal volume was 3 mL irrespective of weight. CONCLUSIONS: Mean IAP in critically ill children is 7 +/- 3 mm Hg. The minimum optimal volume needed to accurately measure IAP by the intravesical method in children is 3 mL. We recommend that 3 mL be the standard instillation volume for IAP measurement by the intravesical method in children. IAP >10 mm Hg should be considered elevated in children.

Variability in pediatric brain death determination and documentation in southern California.

OBJECTIVES: Because the concept of brain death is difficult to define and to apply, we hypothesized that significant variability exists in pediatric brain death determination and documentation. METHODS: Children (0-18 years of age) for whom death was determined with neurologic criteria between January 2000 and December 2004, in southern California, were included. Medical charts were reviewed for documented performance of 14 specific elements derived from the 1987 brain death guidelines and confirmatory testing. RESULTS: A total of 51.2% of children (142 of 277 children) referred to OneLegacy became organ donors. Care locations varied, including PICUs (68%), adult ICUs (29%), and other (3%). One patient was <7 days, 6 were 7 days to 2 months, 22 were 2 months to 1 year, and 113 were >1 year of age. The number of brain death examinations performed was 0 (4 patients), 2 (122 patients), 3 (14 patients), or 4 (2 patients). Recommended intervals between examinations were followed for 18% of patients >1 year of age and for no younger patients. A mean of only 5.5 of 14 examination elements were completed by neurologists and pediatric intensivists and 5.8 by neurosurgeons. No apnea testing was recorded in 60% of cases, and inadequate PaCO(2) increase occurred in more than one half. Cerebral blood flow determination was performed as a confirmatory test 74% of the time (83 of 112 cases), compared with 26% (29 of 112 cases) for electroencephalography alone. CONCLUSIONS: Children suffering brain death are cared for in various locations by a diverse group of specialists. Clinical practice varies greatly from established guidelines, and documentation is incomplete for most patients. Physicians rely on cerebral blood flow measurements more than electroencephalography for confirmatory testing. Codifying clinical and testing criteria into a checklist could lend uniformity and enhance the quality and rigor of this crucial determination.

Outcomes of children with abdominal compartment syndrome.

INTRODUCTION: Abdominal compartment syndrome (ACS) is a problem across all critical care scenarios and is associated with a high mortality. It has not been well described in pediatric populations. OBJECTIVE: To describe the occurrence of ACS in a subset of critically ill pediatric patients and determine its effects on mortality and length of pediatric intensive care stay (PICU LOS). We also aimed to find predictors of mortality and development of ACS. SETTING: 25 bed tertiary pediatric intensive care unit. PATIENTS: Patients less than 50 kg on mechanical ventilation and a urethral catheter. MEASUREMENTS: Intra-abdominal pressures (IAP) were monitored using the intra-vesical technique. ACS was defined as IAP of >12mmHg associated with new organ dysfunction or failure. Demographics, physiologic measures of organ dysfunction, PICU LOS and mortality were monitored. MAIN RESULTS: 14 (4.7%) of 294 eligible patients had ACS. Mortality was 50% among those with ACS versus 8.2% without (p<.001). PICU LOS stay did not differ between groups. No difference in mortality or PICU LOS was seen in primary versus secondaryACS or in patients who underwent abdominal decompression compared to those without decompression. IAP and ACS were independent predictors of mortality (odds ratio 1.53, 95% CI, 1.17- 1.99 and 9.09, 95% CI, 1.07 - 76.84) respectively. IAP and a PRISM score of >17 were predictive of developing ACS. CONCLUSIONS: ACS is a clinical problem that increases the risk of mortality in critically ill children. IAP and PRISM scores may help identify children likely to develop ACS.

Myocardial oxygenation and adenosine release in isolated guinea pig hearts during changes in contractility.

Previous work from this laboratory using near-infrared optical spectroscopy of myoglobin has shown that approximately 20% of the myocardium is hypoxic in buffer-perfused hearts that are perfused with fully oxygenated buffer at 37 degrees C. The present study was undertaken to determine cardiac myoglobin saturation in buffer-perfused hearts when cardiac contractility was increased with epinephrine and decreased during cardiac arrest with KCl. Infusion of epinephrine to achieve a doubling of contractility, as measured by left ventricular maximum pressure change over time (dP/dt), resulted in a decrease in mean myoglobin saturation from 79% at baseline to 65% and a decrease in coronary venous oxygen tension from 155 mmHg at baseline to 85 mmHg. Cardiac arrest with KCl increased mean myoglobin saturation to 100% and coronary venous oxygen tension to 390 mmHg. A previously developed computer model of oxygen transport in the myocardium was used to calculate the probability distribution of intracellular oxygen tension and the hypoxic fraction of the myocardium with an oxygen tension below 0.5 mmHg. The hypoxic fraction of the myocardium was approximately 15% at baseline, increased to approximately 30% during epinephrine infusion, and fell to approximately 0% during cardiac arrest. The coronary venous adenosine concentration changed in parallel with the hypoxic fraction of the myocardium during epinephrine and KCl. It is concluded that catecholamine stimulation of buffer-perfused hearts increases hypoxia in the myocardium and that the increase in venous adenosine concentration is a reflection of the larger hypoxic fraction of myocardium that is releasing adenosine.