Elevated intra-abdominal pressure: A review of current knowledge

Table 1 Effect of intra-abdominal hypertension on different systems

Location	Effect of IAH
Central nervous system	↑ Intracranial pressure
	↓ Cerebral perfusion pressure
	↓ Venous outflow
	↑ Intracerebral venous pooling
Thorax	↑ Intrathoracic pressure
	↑ Inferior vena cava diameter
	↓ Wall compliance
Cardiovascular system	↑ Obstruction of vena cava
	↓ Venous return (preload)
	↓ Cardiac output
	↓ Ventricular compliance and contractility
	↑ Compression of the aorta and systemic vasculature
	↑ Systemic vascular resistance (afterload)
	↑ Compression of pulmonary parenchyma
	↑ Pulmonary vascular resistance
	↑ Central venous pressure
	↑ Pulmonary artery occlusion pressure
Lungs	Atelectasis
	↓Compliance
	↑ Infection rate
	Alveolar volutrauma
	↑ Peak inspiratory pressure
	↑ Mean airway pressure
	↑ Ventilation-perfusion mismatch
	↑ Pulmonary dead space
	↑ PaCO2
	↓ PaO2
Abdomen	↓ Abdominal perfusion pressure
	↓ Wall compliance
	↓ Wall blood flow
	↓ Celiac and mesenteric blood flow
	↑ Mesenteric venous pressure
	↑ Visceral swelling
	↑ Ischaemia
	↑ Feeding intolerance
	↓ Intramucosal pH
	Bacterial translocation
Liver	↓ Portal blood flow
	↓ Hepatic artery blood flow
	↓ Hepatic vein blood flow
	↓ Lactate clearance
Kidney	↓ Renal blood flow
	↑ Renal venous pressure
	↑ Renal vascular resistance
	↓ Glomerular filtration rate
	↓ Diuresis
	↑ Blood urea nitrogen concentration
	↑ Serum creatinine
	↑ Activation of renin-angiotensin-aldosterone axis
	↑ Antidiuretic hormone release

IAH: Intra-abdominal hypertension.