Effect of Patient Positioning on Intracranial Pressures during Laparoscopy
Thursday - September 14, 2017 1:47 pm
Purpose of study was to evaluate Effect of Pneumoperitoneum and Patient Positioning on Intracranial Pressures during Laparoscopy. In the Trendelenburg position, the body is laid supine, or flat on the back with the feet higher than the head by 15-30 degrees. The reverse Trendelenburg position similarly has the body flat, but the head is 15-30 degrees higher than the feet.
In normotensive patients, the head-down tilt increased the preload of both right and left ventricles, increased cardiac output slightly, decreased systemic vascular resistance, and did not change the mean arterial pressure. This effect was probably mediated by baroreceptor stimulation. In hypotensive patients, the Trendelenburg position did not increase preload, slightly increased afterload, and decreased cardiac output. This study failed to document any beneficial hemodynamic effect of the Trendelenburg position in critically ill normo- or hypotensive patients.
Increased intracranial pressure (ICP) is a rise in pressure around brain. It may be due to an increase in the amount of fluid surrounding brain. For example, there may be an increased amount of the cerebrospinal fluid that naturally cushions your brain or an increase in blood in the brain due to trendelenburg position.
Delayed treatment or failure to reduce intracranial pressure can cause temporary brain damage, permanent brain damage, long-term coma, or even death.
When the Trendelenberg position should, and should not, be used
The Trendelenburg position is clinically useful for:
1. Insertion or removal of central venous catheters
2. Certain spinal anaesthetic techniques
The Trendelenburg position is probably not indicated or may have harmful effects in:
1. Resuscitation of patients who are hypotensive
2. Patients in whom mechanical ventilation is difficult, or patients with decreased vital capacity
3. Patients who have increased intracranial pressure
4. Patients who have cerebral oedema
5. Patients who have increased intraocular pressure
6. Patients with ischaemia of the lower limbs
Pneumoperitoneum causes an increase in ICP keeping the pressure limited to 12 or 15mm Hg and decreasing the surgical time and preventing excessive trendelenburg position can minimize this complication.
Although we have insufficient knowledge about the effects of Trendelenburg positions on various hemodynamic parameters, these positions are frequently used to influence cardiac output and blood pressure in critically ill patients.