What are Lundberg waves?
Lundberg (or B) waves, defined as repetitive changes in intracranial pressure (ICP) occurring at frequencies of 0.5 to 2 waves/min, have been attributed to cerebral blood flow fluctuations induced by central nervous system pace-makers or cerebral pressure autoregulation.
How do ICP monitors work?
Intracranial pressure (ICP) monitoring is a diagnostic test that helps your doctors determine if high or low cerebrospinal fluid (CSF) pressure is causing your symptoms. The test measures the pressure in your head directly using a small pressure-sensitive probe that is inserted through the skull.
What is an ICP waveform?
The ICP waveform consists of three components—(1) respiratory waveforms (0.1–0.3 Hz) associated with the respiratory cycle (W2), (2) pulse pressure waveforms (frequency equal to heart rate), and (3) slow vasogenic waveforms (e.g., ‘Lundberg A and B waves’) [54].
What is P2 ICP?
P2 is the “tidal wave” (cool name, ) and represents intracranial compliance. Compliance is defined by change in volume / change in pressure, so a poorly compliant brain will accept any additional volume (blood, CSF, brain swelling) by rapidly increasing ICP.
What causes ICP?
Increased ICP can result from bleeding in the brain, a tumor, stroke, aneurysm, high blood pressure, or brain infection. Treatment focuses on lowering increased intracranial pressure around the brain. Increased ICP has serious complications, including long-term (permanent) brain damage and death.
What is P1 on ICP waveform?
When looking at a single ICP waveform, the examiner can identify 3 peaks (P1, P2 and P3) that correlate with the propagation of the arterial pulse pressure [20,21]. P1 (also referred to as systolic or percussion wave) is produced by the transmission of arterial pressure through the choroid plexus into the ventricles.
What is a wave in ICP?
What is ICP and CPP?
Cerebral perfusion pressure (CPP) is the amount of pressure needed to maintain blood flow to the brain. CPP is regulated by two balanced opposing forces: Mean arterial pressure (MAP) is the driving force that pushes blood into the brain. Intracranial pressure (ICP) is the force that keeps blood out.
What does the P2 wave represent in an ICP waveform?
P2 is the pressure generated within the CSF as a result of the forces generated from both the pulsatile blood vessel and the resistance from the intracranial tissue. The higher the resistance is, the greater the pressure within the CSF and therefore the greater the P2 wave amplitude.
What’s a normal CPP?
Dilation and constriction of the intracranial arterial system maintains appropriate CPP. Cerebral blood flow is relatively well-maintained by autoregulation in a normal state (mean arterial pressure (MAP) between about 60 mmHg and 150 mmHg and an intracranial pressure (ICP) of about 10 mmHg).
How is CPP calculated?
In addition, using arterial pressure (AP), the cerebral perfusion pressure (CPP) can be calculated (CPP = AP-ICP). CPP is important in considering extracranial factors, such as changes in blood volume or arterial pressure, resulting in secondary brain swelling and ischemia.
How do you calculate ICP?
Cerebral perfusion pressure is the primary determinant of cerebral blood flow (CBF). Cerebral perfusion pressure is defined as the difference between the mean arterial pressure (MAP) and ICP (CPP = MAP − ICP). Elevated ICP is a common and life-threatening complication of TBI.
What is Pulsus Dicrotic?
The dicrotic pulse is an abnormal carotid pulse found in conjunction with certain conditions characterised by low cardiac output. It is distinguished by two palpable pulsations, the second of which is diastolic and immediately follows the second heart sound.
What is a jerky pulse?
jerky pulse one in which the artery is suddenly and markedly distended. paradoxical pulse one that markedly decreases in amplitude during inhalation, as often occurs in constrictive pericarditis.
How is ICP and CPP calculated?
CPP is equal to mean arterial pressure (MAP) minus ICP (CPP=MAP−ICP). Because CPP cannot be readily measured, MAP and ICP are used as surrogate measures. Goal CPP should be achieved first by reducing ICP, then optimizing MAP.