How long can the aorta be cross clamped?
The clamping of the aorta excludes the systemic circulation, by definition, thus causing an ischemia. When a long cross-clamping period (longer than 25 min) or a drop in distal aortic pressure below 50–60 mmHg is anticipated, the use of an intraoperative shunt may prevent complications such as paraplegia.
What is the major concern of clamping the aorta?
Aortic cross-clamping decreases renal blood flow from 80% to 90%, resulting in an ischemic insult. The risk is higher in older patients with coronary artery disease, diabetes, or preexisting renal dysfunction. Acute renal failure is a major predictor of increased morbidity and mortality.
What is cardiopulmonary bypass time?
CPB can be used for the induction of total body hypothermia, a state in which the body can be maintained for up to 45 minutes without perfusion (blood flow). If blood flow is stopped at normal body temperature, permanent brain damage normally occurs in three to four minutes – death may follow shortly afterward.
What causes Declamping shock?
declamping phenomenon shock or hypotension following abrupt release of clamps from a large portion of the vascular bed, as from the aorta; apparently caused by transient pooling of blood in a previously ischemic area.
What is a normal cross-clamp time?
In the majority of patients, 30–90 min of cross-clamp time was required. Less than 2% of patients required cross-clamp times greater than 120 min and these patients were excluded for the reasons noted above.
What is a normal cross clamp time?
What is the most dramatic and consistent effect of aortic cross clamping?
Arterial hypertension is the most dramatic and consistent component of the hemodynamic response to aortic cross-clamping.
What is cross clamp time?
Cross-clamp time is an independent predictor of mortality and morbidity in low- and high-risk cardiac patients. Int J Surg.
What is considered a long bypass time?
Conclusions: Prolonged CPB times could predict postoperative clinical events, in particular mortality. To minimize the occurrence of unfavorable adverse outcomes, it is recommended that the CPB/graft time and cumulative CPB time be kept below 56 minutes and 180 minutes respectively.
What is the meaning of Declamping?
[ dē-klăm′pĭng ] n. The occurrence of shock or hypotension following the abrupt release of clamps from a large portion of the vascular bed, such as the aorta, that is believed to be caused by transient pooling of blood in a previously ischemic area.