Reduction In Intra-abdominal Pressure Research Articles

Elevated Intra-Abdominal Pressure in Acute Decompensated Heart Failure: A Potential Contributor to Worsening Renal Function?

This study sought to determine whether changes in intra-abdominal pressure (IAP) with aggressive diuretic or vasodilator therapy are associated with improvement in renal function in acute decompensated heart failure (ADHF). Elevated IAP (>or=8 mm Hg) is associated with intra-abdominal organ dysfunction. There is potential for ascites and visceral edema causing elevated IAP in patients with ADHF. Forty consecutive patients admitted to a specialized heart failure intensive care unit for management of ADHF with intensive medical therapy were studied. The IAP was measured using a simple transvesical technique at time of admission and before removal of the pulmonary artery catheter. In our study cohort (mean age 59 +/- 13 years, mean left ventricular ejection fraction 19 +/- 9%, baseline serum creatinine 2.0 +/- 0.9 mg/dl), the mean baseline IAP was 8 +/- 4 mm Hg, with 24 (60%) patients having elevated IAP. Elevated IAP was associated with worse renal function (p = 0.009). Intensive medical therapy resulted in improvement in both hemodynamic measurements and IAP. A strong correlation (r = 0.77, p < 0.001) was observed between reduction in IAP and improved renal function in patients with baseline elevated IAP. However, changes in IAP or renal function did not correlate with changes in any hemodynamic variable. Elevated IAP is prevalent in patients with ADHF and is associated with impaired renal function. In the setting of intensive medical therapy for ADHF, changes in IAP were better correlated with changes in renal function than any hemodynamic variable.

Management options for hydrothorax complicating peritoneal dialysis.

Hydrothorax as a result of pleuroperitoneal communication occurs in approximately 2% of continuous ambulatory peritoneal dialysis (CAPD) patients. Although our understanding of its mechanisms is incomplete, it is apparent that the key to successful therapy is obliteration of a transdiaphragmatic route of dialysate leakage (pleuroperitoneal communication), possibly coupled with reduction of intra-abdominal pressure. This review corroborated the findings from 10 major population-based case series in which 60 of the 104 cases (58%) were able to resume long-term peritoneal dialysis (PD). Temporary interruption of PD alone was successful in half of them. As compared to this conservative approach, as well as chemical pleurodesis via intercostal chest drain, video-assisted thoracoscopic intervention (including direct pleurodesis and diaphragmatic repair) has shown a promising role. Efficacy of thoracoscopic treatment has been confirmed by several case series from various centers and the demonstration of a success rate in excess of 90%. With accumulating experience using the thoracoscopic technique, it remains to be seen whether this mode of treatment will obviate the traditional closed pleurodesis.

Reduction of abdominal pressure in patients with ascites reduces gastroesophageal reflux.

The effect of the reduction of intra-abdominal pressure on the lower esophageal sphincter pressure (LESP) and the 24-hour pH monitoring were studied in 16 patients with ascites before and after paracentesis. LESP did not change (P > 0.05) with the reduction of intra-abdominal pressure (before paracentesis: 17.48 mmHg and postparacentesis: 18.67 mmHg). The results were divided into two groups according to the achieved reduction in intra-abdominal pressure group A were those in who the reduction was greater than 70% and B consisted of those a reduction of less than 70%. LESP did not change even when results for each group were considered separately (P > 0.05): group A (before: 15.60 mmHg; after: 18.09 mmHg); group B (before: 23.09 mmHg; after: 20.40 mmHg). However the 24-h pH monitoring showed pathological reflux in patients with ascites that was reduced with the paracentesis (P < 0.05; total number of reflux episodes before paracentesis was 520.26, and after, 136.26). All pH-monitoring parameters were statistically different (P < 0.05) before and after the reduction of intra-abdominal pressure for group A but not for group B. LESP does not change significantly (P > 0.05) when the intra-abdominal pressure is significantly reduced (P < 0.05). Patients with ascites showed gastroesophageal reflux. Intra-abdominal pressure reduction greater than 70% lead to a significant reduction in gastroesophageal reflux.

Abdominal Compartment Syndrome with Massive Lower-Extremity Edema Caused by Colonic Obstruction and Distention

Abdominal compartment syndrome is a well-described condition in which increased intraabdominal pressure causes various physiologic derangements with adverse effects on cardiac, pulmonary, and renal function. A patient presented with radiation-induced distal colonic obstruction, abdominal distention, and severe bilateral leg edema. We performed a diverting transverse loop colostomy as treatment for her obstruction. This resulted in massive, spontaneous diuresis with complete resolution of her lower-limb edema. Abdominal compartment syndrome due to colonic obstruction can contribute to the development of lower-extremity edema. Colon decompression with reduction of intra-abdominal pressure can lead to resolution of edema in this situation.

Treatment of intracranial hypertension using nonsurgical abdominal decompression.

Elevated intra-abdominal pressure (IAP) increases intracranial pressure (ICP) and reduces cerebral perfusion pressure (CPP). We evaluated a nonsurgical means of reducing IAP to reverse this process. Swine with a baseline ICP of 25 mm Hg produced by an intracranial balloon catheter were studied. In group 1 (n = 5), IAP was increased by 25 mm Hg. Continuous negative abdominal pressure (CNAP) was then applied. Group 2 (n = 4) had neither IAP elevation nor CNAP. Group 3 (n = 4) had CNAP without IAP elevation. Elevation of IAP by 25 mm Hg above baseline led to deleterious changes in ICP (25.8+/-0.8 to 39.0+/-2.8; p < 0.05) and CPP (85.2+/-2.0 to 64.8+/-2.6; p < 0.05). CNAP led to a reduction in IAP (30.2+/-1.2 to 20.4+/-1.3; p < 0.05) and improvements in cerebral perfusion (ICP, 33+/-2.7; CPP, 74.4+/-1.2; both p < 0.05). Group 2 had stable ICP (25.8+/-0.25 to 28.7+/-1.7; p > 0.05) and CPP (80.8+/-1.4 to 80.5+/-1.8; p > 0.05). In group 3, CNAP decreased cardiac index (2.9+/-0.2 to 1.1+/-0.4; p < 0.05), mean arterial pressure (105.2+/-4.0 to 38.2+/-12.0; p < 0.05), and CPP (74.2+/-4.7 to 14.5+/-12.2; p < 0.05). Elevations in IAP led to increased ICP and decreased CPP. CNAP ameliorated these intracranial disturbances. With normal IAP, CNAP impaired cerebral perfusion.

What causes pre-eclampsia?

Pre-eclampsia remains a leading cause of maternal and fetal morbidity and mortality. Despite extensive research, the mechanisms that cause pre-eclampsia are unknown and it has been considered to be the ‘disease of theories’. Hippocrates wrote in one of his Aphorisms that ‘convulsions take place from either repletion or depletion’. Since then, obstetricians have been divided on the question of which factor accounted for the convulsions observed during childbirth. Some considered that a sudden reduction in intra-abdominal pressure at delivery led to a pooling of blood diverted from the brain, causing collapse of the cerebral blood vessels and convulsions. Others postulated that cerebral congestion, secondary to compression of the abdominal organs by the large uterus, diverted blood to the brain, causing eclamptic convulsions. It is the purpose of this review to examine those theories about the cause of pre-eclampsia for which modern evidence is available. At present, it is believed that the pathological chain of events leading to pre-eclampsia is scheduled in two steps: an absolute or relative placental ischaemia is followed by a diffuse endothelial cell activation, which causes the clinical features of the disease.

Temporary abdominal closure: a prospective evaluation of its effects on renal and respiratory physiology.

This study prospectively analyzed outcomes in 49 consecutive patients undergoing temporary abdominal closure (TAC) between 1993 and 1996 at a single university hospital. There were 37 males and 12 females, mean age was 57 years (range, 25-79 years), mean Acute Physiology and Chronic Health Evaluation score was 27 (+7.8 SD), and mean Simplified Acute Physiology II score was 53.0 (+/-15.4). The reason for TAC was decompression in 22 patients, inability to close the abdomen in 10 patients, to facilitate reexploration for sepsis in 8 patients, and multifactorial in 9 patients. After TAC, there was a significant reduction in intra-abdominal pressure from 24.2+/-9.3 to 14.1+/-5.5 mm Hg and improvement in lung dynamic compliance from 24.1+/-7.9 to 27.6+/-9.4 mL/cm H2O (p < 0.05). Although 10 patients experienced brisk diuresis, there was no significant improvement in renal function; in fact, serum creatinine increased. The median length of stay was 35 days (range, 1-232 days). The mean number of abdominal operations after mesh insertion was 2.6+/-2.4. There were 21 deaths, for a standardized mortality rate of 0.80. Although it achieved significant reductions in abdominal pressures and improved lung dynamic compliance, TAC did not result in improved renal function or patient oxygenation.

ABDOMINAL COMPARTMENT SYNDROME: The Nashville Experience

Intra-abdominal hypertension is an unusual and often lethal syndrome. It is most often seen in critically ill surgical patients. The most important component of therapy is reduction of intra-abdominal pressure. Unfortunately, even with appropriate treatment, mortality is still high.

Pathophysiologic features of a pneumoperitoneum at laparoscopy: A swine model

OBJECTIVE: The aim of this study was to examine local and systemic reactions of the body to a pneumoperitoneum to elucidate potential dangers and risks of laparoscopic procedures. STUDY DESIGN: Laparoscopy was performed on 25 pigs. The pigs were divided into five groups by level of intraabdominal pressure (14 and 18 mm Hg) and gas used (carbon dixoide and air). The effects of the pneumoperitoneum on cardiopulmonary condition and the peritoneal milieu were observed. These effects should be the result of various changes at the mechanical, ventilatory, cellular, hormonal, and immunologic levels. RESULTS: In this animal study marked changes in the peritoneal milieu were observed, and we demonstrated that these changes were dependent on the gas used, intraabdominal pressure, and duration of application. Locally these changes are manifest in the development of severe peritoneal acidosis, hypercapnia, and the release of various mediators. Systemic changes, in particular cardiopulmonary changes, also depend on the intraabdominal pressure and the gas used. CONCLUSION: During conventional pneumoperitoneum the peritoneum might change to a large extent so that the development of new risks are possibly encouraged. A reduction in intraabdominal pressure with the use of carbon dioxide as the insufflation gas should result in normal acid-base balance. (A M J O BSTET G YNECOL 1996;174:132-40.)

MEDICAL TREATMENT OF HIATAL HERNIA.

Generally the initial treatment for symptomatic, uncomplicated hiatal hernia should be a trial of medical therapy. An ulcer-type regimen is instituted to inhibit reflux of gastric juice into the esophagus and reduce gastric hyperacidity. Other objectives are reduction of intra-abdominal pressure and control of aerophagy. Esophagoscopy is an important part of management. Coexisting chronic peptic ulcer of the esophagus, stomach or duodenum or gastric hyperacidity may tip the scales in favor of surgical repair of the hernia.