INTRA-ABDOMINAL PRESSURE MONITORING DURING LÁZARO DA SILVA'S PROCEDURE FOR VENTRAL HERNIA REPAIR: A CROSS-SECTIONAL STUDY.

BACKGROUND: Maintaining normal intra-abdominal pressure (IAP) levels must be one major outcome of any ventral hernia repair, avoiding hypertension or abdominal compartment syndrome. AIMS: To evaluate IAP during ventral hernia repair using Lázaro da Silva's procedure. METHODS: IAP measurements using intravesical pressure were performed during four crucial intraoperative moments. Twenty-eight patients submitted to incisional herniorrhaphy were analyzed. RESULTS: The IAP increased by 0.5 mmHg during the procedure, regardless of the type of prior laparotomy, sex, age, obesity, or hernia width. CONCLUSIONS: Despite the IAP increase observed, Lázaro da Silva's procedure did not result in intra-abdominal hypertension or abdominal compartment syndrome.

Validation of continuous intraabdominal pressure measurement: feasibility and accuracy assessment using a capsular device in in-vivo studies.

BACKGROUND: Monitoring Intraabdominal Pressure (IAP) is essential in critical care, as elevated IAP can lead to severe complications, including Abdominal Compartment Syndrome (ACS). Advances in technology, such as digital capsules, have opened new avenues for measuring IAP non-invasively. This study assesses the feasibility and effectiveness of using a capsular device for IAP measurement in an animal model. METHOD: In our controlled experiment, we anesthetized pigs and simulated elevated IAP conditions by infusing CO2 into the peritoneal cavity. We compared IAP measurements obtained from three different methods: an intravesical catheter (IAPivp), a capsular device (IAPdot), and a direct peritoneal catheter (IAPdir). The data from these methods were analyzed to evaluate agreement and accuracy. RESULTS: The capsular sensor (IAPdot) provided continuous and accurate detection of IAP over 144 h, with a total of 53,065,487 measurement triplets recorded. The correlation coefficient (R²) between IAPdot and IAPdir was excellent at 0.9241, demonstrating high agreement. Similarly, IAPivp and IAPdir showed strong correlation with an R² of 0.9168. CONCLUSION: The use of capsular sensors for continuous and accurate assessment of IAP marks a significant advancement in the field of critical care monitoring. The high correlation between measurements from different locations and methods underscores the potential of capsular devices to transform clinical practices by providing reliable, non-invasive IAP monitoring.

[Abdominal compartment syndrome in visceral surgery and intensive care medicine : Causes, prevention, detection, treatment]. / Abdominelles Kompartmentsyndrom in der Viszeralchirurgie und Intensivmedizin : Ursachen, Prävention, Erkennung, Therapie.

An increased intra-abdominal pressure can result in a manifest abdominal compartment syndrome (ACS) with significant organ damage, which is a life-threatening situation associated with a high mortality. Although the etiology is manifold and critically ill patients on the intensive care unit are particularly endangered, the disease is often not diagnosed even though the measurement of bladder pressure is available as a simple and standardized method; however, particularly the early detection of an increased intra-abdominal pressure is decisive in order to prevent the occurrence of a manifest ACS with (multi)organ failure by means of conservative measures. In cases of a conservative refractory situation, decompressive laparotomy is indicated.

The role of Cushing's reflex and the vasopressin-mediated oligoanuric response to intracranial hypertension in patients with abdominal compartment syndrome.

BACKGROUND: We examined the link between increased intra-abdominal pressure, intracranial pressure, and vasopressin release as a potential mechanism. Intra-abdominal pressure, produced by abdominal-cavity insufflation with carbon dioxide (CO2) during laparoscopic abdominal procedures to facilitate visualization, is associated with various complications, including arterial hypertension and oliguria. METHODS: Mean arterial pressure, optic nerve sheath diameter, measured as a proxy for intracranial pressure, plasma vasopressin, serum and urine osmolarity, and urine output were measured 4 times during laparoscopic sleeve gastrectomy in 42 patients: before insufflation with CO2 (T0); after insufflation to 15 cm water (H2O) pressure, with 5 cm H2O positive end-expiratory pressure (T1); after positive end-expiratory pressure was raised to 10 cm H2O (T2); and after a return to the baseline state (T3). Mean values at T0 to T3 and the directional consistency of changes (increase/decrease/ unchanged) were compared among the 4 data-collection points. RESULTS: Statistically significant elevations (all P ≤ .001) were noted from T0 to T1 and from T0 to T2 in mean arterial pressure, optic nerve sheath diameter, and vasopressin, followed by decreases at T3. For optic nerve sheath diameter and vasopressin, the increases at T1 and T2 occurred in 98% and 100% of patients, ultimately exceeding normal levels in 88 and 97%, respectively. Conversely, urine output fell from T0 to T1 and T2 by 60.9 and 73.4%, decreasing in 88.1% of patients (all P < .001). Patients with class II obesity exhibited statistically greater increases in optic nerve sheath diameter and vasopressin, but statistically less impact on urine output, than patients with class III obesity. CONCLUSION: Increased mean arterial pressure, intracranial pressure, and vasopressin release appear to be intermediary steps between increased intra-abdominal pressure and oliguria. Further research is necessary to determine any causative links between these physiological changes.

Do we have the guts to go? The abdominal compartment, intra-abdominal hypertension, the human microbiome and exploration class space missions.

Humans are destined to explore space, yet critical illness and injury may be catastrophically limiting for extraterrestrial travel. Humans are superorganisms living in symbiosis with their microbiomes, whose genetic diversity dwarfs that of humans. Symbiosis is critical and imbalances are associated with disease, occurring within hours of serious illness and injury. There are many characteristics of space flight that negatively influence the microbiome, especially deep space itself, with its increased radiation and absence of gravity. Prolonged weightlessness causes many physiologic changes that are detrimental; some resemble aging and will adversely affect the ability to tolerate critical illness or injury and subsequent treatment. Critical illness-induced intra-abdominal hypertension (IAH) may induce malperfusion of both the viscera and microbiome, with potentially catastrophic effects. Evidence from animal models confirms profound IAH effects on the gut, namely ischemia and disruption of barrier function, mechanistically linking IAH to resultant organ dysfunction. Therefore, a pathologic dysbiome, space-induced immune dysfunction and a diminished cardiorespiratory reserve with exacerbated susceptibility to IAH, imply that a space-deconditioned astronaut will be vulnerable to IAH-induced gut malperfusion. This sets the stage for severe gut ischemia and massive biomediator generation in an astronaut with reduced cardiorespiratory/immunological capacity. Fortunately, experiments in weightless analogue environments suggest that IAH may be ameliorated by conformational abdominal wall changes and a resetting of thoracoabdominal mechanics. Thus, review of the interactions of physiologic changes with prolonged weightlessness and IAH is required to identify appropriate questions for planning exploration class space surgical care.

L'humanité est à l'aube d'une nouvelle ère d'exploration spatiale, mais le risque de maladies et blessures graves pourrait restreindre de manière catastrophique le potentiel des voyages dans l'espace. L'être humain est un superorganisme vivant en symbiose avec son microbiote, dont la diversité génétique éclipse celle de l'hôte. Cette symbiose est essentielle : tout déséquilibre est associé à une dégradation de l'état de santé dans les heures suivant l'occurrence d'une blessure ou d'une maladie grave. Bon nombre de caractéristiques propres au vol spatial ont des répercussions négatives sur le microbiote; l'espace lointain présente des dangers particuliers en raison de l'exposition accrue au rayonnement et de l'absence de gravité. L'exposition prolongée à l'apesanteur cause une myriade de changements physiologiques nuisant à la santé. Certains ressemblent à des processus de vieillissement et réduiront la capacité à tolérer une blessure ou une maladie grave et son traitement. L'hypertension intra-abdominale (HIA) causée par une maladie grave peut réduire la perfusion des viscères et du microbiote, ce qui peut avoir des conséquences catastrophiques. Des études sur modèle animal ont confirmé les effets profondément délétères de l'HIA sur les intestins par l'apparition d'une ischémie et une altération de la barrière intestinale; cette découverte permettrait d'établir un lien mécanistique entre l'HIA et la défaillance d'organes résultante. Par conséquent, une dysbiose pathologique, associée à un dysfonctionnement immunitaire en apesanteur et à une réduction de la réserve cardiorespiratoire accompagnée d'une exacerbation de la susceptibilité à l'HIA, pourrait signifier qu'un astronaute exposé à l'effet déconditionnant de l'apesanteur serait vulnérable aux problèmes de perfusion de l'intestin découlant de l'HIA. Ce problème pourrait à son tour mener à une ischémie intestinale grave et à une production massive de biomédiateurs chez un astronaute présentant déjà une capacité cardiorespiratoire et immunitaire réduite. Heureusement, des expériences dans des environnements simulant l'apesanteur semblent indiquer que les effets de l'HIA pourraient être contrés par des changements conformationnels de la paroi abdominale et un rétablissement de la mécanique thoracoabdominale. Par conséquent, un examen des interactions des changements physiologiques associés à un état d'apesanteur prolongé et à l'HIA est requis pour déterminer les questions à poser afin de planifier adéquatement les soins chirurgicaux en contexte d'exploration spatiale.

Hipertensão intra-abdominal e síndrome compartimental abdominal: repercussões e tratamento clínico no paciente crítico / Intra-abdominal hypertension and abdominal compartment syndrome: repercussions and clinical treatment in critically ill patients

A hipertensão intra-abdominal e a síndrome compartimental abdominal foram durante muitas décadas mal compreendidas e dissociadas de suas repercussões clínicas. Trata-se de um distúrbio que pode levar à disfunção de múltiplos órgãos devido ao desequilíbrio circulatório desencadeado pelo aumento de pressão no compartimento abdominal. As manifestações envolvem os sistemas cardiovascular, respiratório, renal, nervoso e gastrintestinal e estão largamente relacionadas com o fator de morbimortalidade no paciente crítico. A despeito da importância clínica, a hipertensão intra-abdominal e à síndrome compartimental abdominal ainda são temas pouco dominados pelos médicos, e fazem-se necessários o reconhecimento precoce e o estabelecimento de estratégias clínicas objetivas no contexto de uma síndrome com desfecho tão desfavorável. Portanto, foi realizada uma revisão da literatura não sistematizada com objetivo de compreender os principais pontos sobre definições, prevalência, fatores de risco, fisiopatologia, diagnóstico e tratamento acerca da hipertensão intra-abdominal e a síndrome compartimental abdominal.

Intra-abdominal hypertension and abdominal compartment syndrome have been, for many decades, poorly understood and dissociated from their clinical repercussions. It is a disorder that can lead to organ dysfunction due to circulatory impairment triggered by increased pressure in the abdominal compartment. The manifestations involve cardiovascular, respiratory, renal, nervous, and gastrointestinal systems, and are widely associated with significant morbidity and mortality in critically ill patients. Despite their clinical importance, intra-abdominal hypertension and abdominal compartment syndrome are still not sufficiently known by physicians and, early recognition and the establishment of objective clinical strategies for managing these highly morbid syndromes are required. Therefore, a non-systematized review was carried out to understand the main points about definitions, prevalence, risk factors, pathophysiology, diagnosis, and treatment of intra-abdominal hypertension and abdominal compartment syndrome.

Successful intraoperative management in patients with abdominal compartment syndrome induced by giant liposarcomas: Two case reports.

RATIONALE: Giant intra-abdominal liposarcomas weighing over 20 kg often increase the intra-abdominal pressure (IAP), which has severe effects on the cardiovascular and respiratory systems. Abdominal compartment syndrome is defined typically as the combination of a raised IAP of 20 mm Hg or higher and new onset of organ dysfunction or failure. The anesthetic management and perioperative management are very challenging. PATIENTS CONCERNS: We presented 2 patients with rare giant growing liposarcoma of the abdomen, weighing 21 kg and over 35 kg, respectively. Circulatory management was particularly difficult in the first case, while respiratory management and massive blood loss was very challenging in the second one. DIAGNOSIS: With a computed tomography scan and peritoneal-to-abdominal height ratio measurement, preoperatively the risk of developing intra-abdominal hypertension and abdominal compartment syndrome was recognized early in each patient. The inferior vena cava and right atrium of the first patient was compressed and malformed due to the uplifted diaphragm, while there was severe decreased lung volume and increased airway resistance, because of rare giant retroperitoneal liposarcomas in the second case. Histologic examination revealed dedifferentiated liposarcoma in both cases. INTERVENTIONS: Both of the patients underwent resection surgery with multiple monitoring; transesophageal echocardiography monitoring in the first case and pressure-controlled ventilation volume guaranteed mechanical ventilation mode in both cases. OUTCOMES: Intraoperatively and postoperatively no cardiopulmonary complications in both patients. The first patient was discharged without any complications on postoperative day 10, and the second patient underwent another surgery because of anastomotic leakage resulting from bowel resection. LESSONS: Multiple monitorings, in particular transesophageal echocardiography should be considered in patients with increased IAP due to a giant mass, while an appropriate lung protection ventilation strategy is crucial in these patients.

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.

Basic Fibroblast Growth Factor (bFGF) Protects the Blood-Brain Barrier by Binding of FGFR1 and Activating the ERK Signaling Pathway After Intra-Abdominal Hypertension and Traumatic Brain Injury.

BACKGROUND Intra-abdominal hypertension (IAH) is associated with high morbidity and mortality. IAH leads to intra-abdominal tissue damage and causes dysfunction in distal organs such as the brain. The effect of a combined injury due to IAH and traumatic brain injury (TBI) on the integrity of the blood-brain barrier (BBB) has not been investigated. MATERIAL AND METHODS Intracranial pressure (ICP) monitoring, brain water content, EB permeability detection, immunofluorescence staining, real-time PCR, and Western blot analysis were used to examine the effects of IAH and TBI on the BBB in rats, and to characterize the protective effects of basic fibroblast growth factor (bFGF) on combined injury-induced BBB damage. RESULTS Combined injury from IAH and TBI to the BBB resulted in brain edema and increased intracranial pressure. The effects of bFGF on alleviating the rat BBB injuries were determined, indicating that bFGF regulated the expression levels of the tight junction (TJ), adhesion junction (AJ), matrix metalloproteinase (MMP), and IL-1ß, as well as reduced BBB permeability, brain edema, and intracranial pressure. Moreover, the FGFR1 antagonist PD 173074 and the ERK antagonist PD 98059 decreased the protective effects of bFGF. CONCLUSIONS bFGF effectively protected the BBB from damage caused by combined injury from IAH and TBI, and binding of FGFR1 and activation of the ERK signaling pathway was involved in these effects.

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

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

The Cushing reflex and the vasopressin-mediated hemodynamic response to increased intracranial pressure during acute elevations in intraabdominal pressure.

BACKGROUND: Abdominal compartment syndrome has been linked to detrimental hemodynamic side effects that include increased intracranial pressure and diminished renal function, but the mechanisms behind this continue to be elucidated. In this study, we sought to investigate any direct association between acute elevations in intra-abdominal pressure and intracranial hypertension during experimentally induced abdominal compartment syndrome and between acutely elevated intracranial pressure and the hemodynamic response that might be elicited by a vasopressin-induced Cushing reflex affecting urine osmolality and urine output. The aim of this study is to explain the Cushing reflex and the vasopressin-mediated hemodynamic response to intracranial pressure during acute elevations in intra-abdominal pressure. METHODS: We measured intra-abdominal pressure, intrathoracic pressure, optic nerve sheath diameter as an indirect sign of intracranial pressure, vasopressin levels in blood, urine osmolality, and urine output at 4 time points during surgery in 16 patients undergoing sleeve gastrectomy for morbid obesity. Values for the 4 time points were compared by repeated-measures analysis of variance. RESULTS: More than 50-fold elevations in serum vasopressin paralleled increases in optic nerve sheath diameter, rising throughout prepneumoperitoneum and tapering off afterward, in conjunction with a marked decrease in urine but not serum osmolality. Mean arterial pressure rose transiently during pneumoperitoneum without elevated positive end-expiratory pressure but was not significantly elevated thereafter. CONCLUSIONS: These findings support our hypothesis that the oliguric response observed in abdominal compartment syndrome might be the result of the acutely elevated intra-abdominal pressure triggering increased intrathoracic pressure, decreased venous outflow from the central nervous system, increased intracranial pressure, and resultant vasopressin release via a Cushing reflex.

Abdominal perfusion pressure is superior from intra-abdominal pressure to detect deterioration of renal perfusion in critically Ill patients.

BACKGROUND: Intra-abdominal hypertension (IAH) is a frequent cause of acute kidney injury (AKI) among critically ill patients who have risk factors. This study aimed to determine the relation between Abdominal Perfusion Pressure (APP) and AKI showed by the Doppler-based renal resistive index (RRI). METHODS: In this study, 38 patients older than 18 years old who received mechanical ventilation and had risk factors for the development of IAH were prospectively studied. All measurements and parameters were divided into two groups according to renal dysfunction (Group I: RRI <0.72 vs Group II: RRI >0.72). RESULTS: The mean IAPs were not significant between the groups, 11.5±6.9 mm Hg in Group I (n=35) and 13.5±5.8 in Group II (n=33), respectively. APPs were statistically higher in Group I (81.2±13.6) than Group II (66.4±9.5) (p<0.001). The AUC for the association between APP at RRI >0.72 was 0.802 (p<0.001), with the APP ≤72 mmHg having a sensitivity of the 76% (95% CI 58-89%) and a specificity of 71% (95% CI 54-85%). CONCLUSION: Our findings suggest that an APP with a threshold of ≤72 mmHg is associated with a significant increase in renal RRI, which may be predictive of worsening of renal perfusion.

Polycompartment syndrome - intra-abdominal pressure measurement.

Intra-abdominal hypertension and the abdominal compartment syndrome are well-known, serious, life-threatening clinical entities in acute care surgery. A common characteristic of these syndromes is the permanent and irreversible damage that may affect the organs which can be found inside the given compartment if quick intervention cannot be provided. All factors which may and can lead to a sudden increase in the intra-abdominal pressure can be found among the triggering factors of abdominal compartment syndrome. Despite the modern and quick diagnostics, and the adequate surgical interventions performed in time, the mortality of this syndrome is extremely high (38-71%). It affects practically all vital organ systems: cardiovascular, respiratory, urinary and central nervous system. There are four major compartments in the human body: the head, the chest, the abdomen and the extremities. When two or more compartments have elevated pressures the name of the clinical entity is polycompartment syndrome, first described in 2007. The only possible way of establishing the diagnosis is to measure the intra-abdominal pressure, a widespread manner of which is the measurement through the bladder. Treatment of abdominal and polycompartment syndrome is nearly always surgical decompression with temporary abdominal wall closure or open abdominal treatment. Clinicians need to be aware of the real existence of polycompartment syndrome and the complex and constant interplay of raised pressure between compartments. This highlights the importance of research and development of new intra-abdominal pressure measurement techniques.

Editor's Choice - Abdominal Compartment Syndrome after Surgery for Abdominal Aortic Aneurysm: Subgroups, Risk Factors, and Outcome.

OBJECTIVES: Abdominal compartment syndrome (ACS) is a serious complication after abdominal aortic aneurysm (AAA) repair. The aim was to investigate outcome among subgroups and factors associated with outcome, with emphasis on the duration of intra-abdominal hypertension before treatment. METHODS: Since 2008, ACS and decompressive laparotomy (DL) after AAA repair are registered prospectively in the Swedish vascular registry (Swedvasc). Registry data and case records were reviewed. Subgroups were defined by main pathophysiological finding at DL, timing of DL after AAA repair, and treatment modality. RESULTS: During 2008-2015, 120 of 8765 patients undergoing surgery for infrarenal AAA developed post-operative ACS (1.4%). Eighty-three followed ruptured AAA (rAAA); 45 open surgical repairs (OSR) and 38 endovascular (EVAR), and thirty-seven after intact AAA (iAAA); 30 OSR and seven EVAR. The main pathophysiological findings at DL were bowel ischaemia in 27 (23.3%), post-operative bleeding in 34 (29.3%), and general oedema in 55 (47.4%). DL was performed <24 hours after AAA repair in 56 (48.7%), 24-48 hours in 30 (26.1%), and >48 hours in 29 patients (25.2%). The overall 90 day mortality was 50.0%, neither different depending on main pathophysiological finding, nor on the timing of DL. In multivariable regression analysis, age was a predictor of mortality (p = .017), while duration of intra-abdominal hypertension (IAH) prior to DL predicted the need for renal replacement therapy (RRT) (p = .033). DL was performed earlier after EVAR compared with OSR in rAAA (p < .001). CONCLUSIONS: Mortality in ACS was high, irrespective of the main pathophysiological finding and timing of DL. The duration of IAH prior to DL predicted the need for RRT. DL was performed earlier after EVAR than after OSR for rAAA, underlining the importance of monitoring IAP after EVAR for rAAA.

Effect of intra-abdominal hypertension on plasma exogenous creatinine clearance in conscious and anesthetized dogs.

OBJECTIVE: To evaluate the effect of intra-abdominal pressure (IAP) on plasma exogenous creatinine clearance in both conscious and anesthetized dog models using a balloon technique to generate intra-abdominal hypertension. DESIGN: Prospective, cross-over, experimental study. SETTING: University-based small animal research facility. ANIMALS: Six healthy male Beagle dogs. INTERVENTIONS: A balloon device comprising a Foley urinary catheter and latex balloon was placed in the intra-abdominal cavity. Plasma exogenous creatinine clearance was compared after intravenous administration of exogenous creatinine solution at 80 mg/kg under 4 different treatment conditions as follows: control and IAP levels of 25 mm Hg in conscious dogs and control and IAP levels of 25 mm Hg in anesthetized dogs (CC, C25, AC, and A25, respectively). Samples were obtained before (T0) and 10, 20, 30, 60, 90, 120, 240, 360, 480, and 600 min after administration of creatinine in all treatment groups. MEASUREMENTS AND MAIN RESULTS: There were no significant differences in plasma creatinine concentration for CC, AC, and C25 during the treatment period. However, in the A25 treatment condition, the plasma creatinine concentration increased significantly at 10, 20, 30, 60, 90, and 120 min after administration of creatinine (P < 0.05). Plasma creatinine clearances were 5.0 ± 0.5, 4.7 ± 1.2, 5.5 ± 0.9, and 2.5 ± 0.5 mL/kg/min for 600 min (CC, AC, C25, and A25, respectively). In the A25 treatment condition, the plasma exogenous creatinine clearance decreased significantly to 50%, 47%, and 55% of that under control conditions (CC, AC, and C25, respectively). After decompression of the abdomen, plasma creatinine concentrations declined rapidly and returned to basal concentrations. CONCLUSIONS: Intra-abdominal hypertension under general anesthesia could cause renal hypoperfusion. Timely decompression may improve the outcome of acutely increased IAP when surgery and/or general anesthesia is required in canine patients.

Respiratory Mechanics, Lung Recruitability, and Gas Exchange in Pulmonary and Extrapulmonary Acute Respiratory Distress Syndrome.

OBJECTIVES: Acute respiratory distress syndrome is a clinical syndrome characterized by a refractory hypoxemia due to an inflammatory and high permeability pulmonary edema secondary to direct or indirect lung insult (pulmonary and extrapulmonary form). Aim of this study was to evaluate in a large database of acute respiratory distress syndrome patients, the pulmonary versus extrapulmonary form in terms of respiratory mechanics, lung recruitment, gas exchange, and positive end-expiratory pressure response. DESIGN: A secondary analysis of previously published data. PATIENTS: One-hundred eighty-one sedated and paralyzed acute respiratory distress syndrome patients (age 60 yr [46-72 yr], body mass index 25 kg/m [22-28 kg/m], and PaO2/FIO2 184 ± 66). INTERVENTIONS: Lung CT scan performed at 5 and 45 cm H2O. Two levels of positive end-expiratory pressure (5 and 15 cm H2O) were randomly applied. MEASUREMENTS AND MAIN RESULTS: Ninety-seven and 84 patients had a pulmonary and extrapulmonary acute respiratory distress syndrome. The median time from intensive care admission to the CT scan and respiratory mechanics analysis was 4 days (interquartile range, 2-6). At both positive end-expiratory pressure levels, pulmonary acute respiratory distress syndrome presented a significantly lower PaO2/FIO2 and higher physiologic dead space compared with extrapulmonary acute respiratory distress syndrome. The lung and chest wall elastance were similar between groups. The intra-abdominal pressure was significantly higher in extrapulmonary compared with pulmonary acute respiratory distress syndrome (10 mm Hg [7-12 mm Hg] vs 7 mm Hg [5-8 mm Hg]). The lung weight and lung recruitability were significantly higher in pulmonary acute respiratory distress syndrome (1,534 g [1,286-1,835 g] vs 1,342 g [1,090-1,507 g] and 16% [9-25%] vs 9% [5-14%]). CONCLUSIONS: In the early stage, pulmonary acute respiratory distress syndrome is characterized by a greater impairment of gas exchange and higher lung recruitability. The recognition of the origin of acute respiratory distress syndrome is important for a more customized ventilatory management.

Electro-acupuncture attenuates inflammatory responses and intraabdominal pressure in septic patients: A randomized controlled trial.

BACKGROUND: A pathological increase in intraabdominal pressure (IAP) and inflammatory responses have negative effects on splanchnic, respiratory, cardiovascular, renal, and neurological function in septic patients with intestinal dysfunction. Electro-acupuncture (EA) has been evidenced to have a bidirectional neuron-endocrine-immune system regulating effect in patients with intestinal dysfunction. The purpose of current study was to evaluate the effects of EA at "Zusanli" (ST36) and "Shangjuxu" (ST37) on inflammatory responses and IAP in septic patients with intestinal dysfunction manifested syndrome of obstruction of the bowels Qi. METHODS: Eighty-two septic patients with intestinal dysfunction manifested syndrome of obstruction of the bowels Qi were randomly assigned to control group (n = 41) and EA group (n = 41). Patients in control group were given conventional therapies including fluid resuscitation, antiinfection, vasoactive agents, mechanical ventilation (MV), supply of enteral nutrition, and glutamine as soon as possible. In addition to conventional therapies, patients in EA group underwent 20-minutes of EA at ST36-ST37 twice a day for 5 days. At baseline, posttreatment 1, 3, and 7 days, serum levels of tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß) and IAP levels, were measured, respectively. And days on MV, length of stay in intensive care unit (ICU) and 28 days mortality were recorded. RESULTS: The serum levels of TNF-α and IL-1ß and IAP levels at posttreatment 1, 3, and 7 days were lower significantly in the EA group compared with the control group (mean [SD]; 61.03 [20.39] vs 79.28 [20.69]; P < .005, mean [SD]; 35.34 [18.75] vs 66.53 [30.43]; P < .005 and mean [SD]; 20.32 [11.30] vs 32.99 [20.62]; P = .001, respectively, TNF-α. Mean [SD]; 14.11 [5.21] vs 16.72 [5.59]; P = .032, mean [SD]; 9.02 [3.62] vs 12.10 [4.13]; P = .001 and mean [SD]; 5.11 [1.79] vs 8.19 [2.99]; P < .005, respectively, IL-1ß. Mean [SD]; 14.83 [5.58] vs 17.55 [3.37]; P = .009, mean [SD]; 11.20 [2.57] vs 14.85 [3.01]; P < .005 and mean [SD]; 8.62 [2.55] vs 11.25 [2.72]; P < .005, respectively, IAP). There were no significant differences in the duration of MV, length of stay in ICU, and 28d mortality between the groups. CONCLUSION: EA at ST36-ST37 attenuated inflammatory responses through reduction in serum levels of TNF-α and IL-1ß and IAP in septic patients with intestinal dysfunction manifested syndrome of obstruction of the bowels Qi.