Make sure you know all of the things on this ventilator
- evaluate health
- guide treatment
- evaluate effects of treatment
Gives you regular/ continuous recording and evaluation of physiological functioning
What can be monitored?
- general systemic observations
- cardiovascular system
- respiratory system
- renal/ kidney
Why do physios need to know about monitoring?
- treating pts who are monitored
- need to use the information from monitoring to guide management decisions
- safety with moving pts and handling monitoring equipment (dont want to pull something out)
What are some things you generally observe?
- Obs- frequency depends on the status of the pt
- obs are on bed chart in general ward setting
- obs are on flw chart in critical care setting
How does the monitoring system work?
- monitoring involves the sensing of physiological parameters and then turning this into a displace
- very complex but involves:
* a sensor to pick up physiological change
* an amplifier to increase the magnitude of the signal
* a recording/ displace of the signal
- transducer turn pressure changes into waveform display
- pressure transducer- piezoeletric crystal which converts pressure canges into a voltage change then converted to a trace
- pressure transducers need to be zeroed against the point at which the catheter tip isassume to rest- for cardiac pressures- normally 4ICS, M.A.L
- the transducer needs to be in the right place for it to deliver an accurate reading- haemodynamic messures = RA (point of right atrium when you stand up)
What is a non invasive way to measure the CVS?
What are some invasive ways for haemodynamic monitoring?
- CO and chamber pressures
- PAP (pulmonary artery pressure)
- PCWP (pulmonary capillary wedge pressure)
What is the normal pressure for PCWP?
- pulmonary capillary wedge pressure
How do you work out MAP?
MAP = DBP + SBP - DBP/ 3
What is the normal value for MAP?
How do u measure BP?
How do you measure arterial blood pressure?
- arterial blood line
- transducer needs to be at the level of the right atrium
- movt may compromise trace
What are the parts of an arterial waveform?
- arterial BP
- systolic pressure (peak)
- dichrotic notch- need this trace to know if it is an accurate reading
- diastolic pressure
- pulse pressure is all of the above
- MAP- straight line thru reading
- for more info look at lecture
Arterial BP picture
What other tests can be done via an arterial line?
What is CVP?
- central venous pressure
How is CVP measured?
- thru a venous line from the SVC (superior vena cava) (right arterial pressure)
What does a measurement of the CVP estimate?
- intravascular volume status
- RV preload
What is the usual range for CVP?
Note when dead CVP= 5
- not overly useful but good for understanding fluid levels/ balance
What is a type of pulmonary artery catheter?
- swan ganz catheter
Would you mobilise someone with a Pulmonary artery catheter?
- at lot of places wont let you
What are some of the things pulmonary catheters measure?
- pulmonary artery pressure
- pulmonary wedge pressure
Describe the bits of a pulmonary artery catheter
- balloon tipped, flow directed catheter
- mulitple lumen- along tube
- distal port PA
- proximal part- CVP
- indicated when precise measurements of cardiac status are neede
- not used alot
PA catheter pictures
When the balloon inflated with a pulmonary artery catheter what is it measuring?
- once it occludes the PA it is measuring the PCWP
what is the normal PCWP?
What is pulmonary capillary wedge pressure?
- pressure in the pulmonary capillaries
- unrestricted vascular channel thru the PA, pul vasc bed, PV, LA and LV (when mitral open)
- reflection of the pressures in the left atrium and therefore left ventricular diastolic (LVEDP)
- if LVEDP increases there is an increase is LVEDV - volume
- also measure pulmonary fluid overload
What does a high PWCP mean?
- pulmonary congestion- 18-20 (interstitual)
-pulmonary oedema if >20-30 (fluid in arterial space)
- if colloid osmotic pressure is decreased (albium) pulmonary oedema will occur at a lower PCWP
When is pulmonary congestion evident?
- PCWP 18-20
When is pulmonary oedema evident with PCWP?
- fluid in arterial space
What does a low PCWP mean?
What is hypovolaemia?
is a state of decreased blood volume; more specifically, decrease in volume of blood plasma
What does it mean if you have a high PAP?
- pulmonary disease and pulmonary vascular disease
-increased pulmonary blood flow (left to right shunt)
- positive pressure ventilation
How is cardiac output measured?
- temp change
What is a normal CO?
What is the cardiac index in relation to CO?
WHat are some complications of a pulmonary artery catheter?
- pulmonary infection
- balloon rupture
- damage to PA
- thrombolitic effects
- kinking or twisting of the line
These are the reasons why they are moving away from these
What is IABP?
- intra- aortic balloon pump
- form of cardiac support
- used for pts waiting for heart replacements
- helps increase pressures
What are the effects of IABP?
- increases LVEDP
- ↑ coronary blood flow
- decreases LV afterload
- increases CO
- decreases work- decrease oxygen consumption
- increase diasotlic pressure for blood to get around
- guided by an ECG
Where does the IABP sit?
- in the arch of the aorta
- inflated balloon- on a systolic contraction
Is pulmonary artery pressure higher or lower than normal artery pressure?
What is pulmonary artery pressure more influenced by?
- respiratory status and right heart function than PCWP
- Not PAPD is closely related to PCWP
What do you need to be careful about with pts with IABP?
- moving ECG lines
- Dont do percs and vibes
- Don't sit up past 30 degrees hip flex
What will you see with both PAP and PCWP in relation to primary cardiac disorder?
- both will be affected
- heart failure
What are the indications for cardiac support- IABP?
- heart failure
- failure to wean from CPB (cardiopulmonary bypass) eg post cardiac curgery
- prophylatic- transplant
What are some complications of cardiac support IABP?
- limb ischaemia
- vascular trauma- dissection of artery
- balloon rupture
- haematological complications
- malposition- kinking
What are the different types of Cardiac support?
What is VAD cardiac support?
- ventricular assist device
- helps the ventricles work
- temporary device- can be external or implantable
- can be a continuous flow or not
How does the VAD cardiac support work?
- blood withdrawn from the heart chamber
- pumped through device
- returned to outflow (aorta/PA)
What are the indications for VAD?
- bridge transplant
- post op heart failure
What is the cardiac support ECMO?
- extra corporeal membrane oxygenation
- bi- ventricular bypass
- used recently for influenza outbreaks
- being used more and more
- if pt very ill place them on their belly
Things monitored with respiratory system
- arterial blood gases
- end tidal CO2
- ventilator settings
What is measure with the CNS?
Why is ICP measured?
- traumatic brain injury
-trying to prevent secondary complicaitons
Where does the catheter sit to measure ICP?
- near the site of the lesion
- it is linked to a transducer which converts pressure to a plethymographic trace and number
What are your options when measuring ICP?
- Epidural - not a accurate
- subarachnoid/ subdural
What is another was CNS can be monitored?
- CPP (MAP- ICP)
- glascow coma scale
How do you calculate CPP?
MAP - ICP
What is ARF?
- acute renal failure
What is CRF?
- chronic renal failure
When is renal replacement therapy conducted/ indications
- mulitorgan failure
- if urea and creatine are rising above normal levels
What are the aims of renal therapy?
- control fluid balance
- control electrolyte balance
- control acid base
- get rid of toxins and drugs
What is dialysis based on?
- the removal of solutes and water via a semipermeable membrane- either biological or artificial
WHat are your options for renal replacement therapy?
- arterial or venous
- external pump or own driving pressure
- haemofiltration or haemodialysis
WHat does conventional haemodialysis involve?
- blood pumped through extracorporeal system, separated by a semipermeable membrane from a dialystate soution- diffusion of substances across an electrochemical gradient, fluid goes across by haemostatic pressure
- poorly tolerated by critically ill pts
-take out and clean then put back in
What is haemofiltraion (HF)?
- removal of water and solutes by diffusion and convection
- hydrostatic pressure drives filtrate through the membrane and solutes are taken across
- lost liquid is replaced with plasma
- slow- takes 24hrs
- pressure changes affect how well it works
- can be used continuously
What is haemofiltration also known as?
- CVVHD- continuous, veno- venous haemofilations with dialysis
- CAVHD- continuous, arteriovenous haemofiltration with dialysis
- CRRT- continuous replacement therapy
What is peritoneal dialysis?
- use the peritoneum as a semipermiable membrace
- not as effective as HD- therefore not used in critically ill patients
What are complications with peritoneal dialysis?
- impair diaphragm function
- cant walk around with it
What are some important points?
- know what the monitors are- ask and what info u can get from them
- the equipment itself doesnt have CI to physio- the underlying pathology might be
- dont pull stuff out
- alarms- know what to do if they go off
- treating pts- make sure transducers are at the right level, monitor pt, safety, stop and check etc