Ensure that patient and health care provider safety standards are met during this procedure including:

  • Risk assessment and appropriate PPE
  • 4 Moments of Hand Hygiene
  • Procedural Safety Pause is performed
  • Two patient identification
  • Safe patient handling practices
  • Biomedical waste disposal policies
  1. Monitor ECG
  2. Monitor Cardiovascular System
  3. Maintain Hemodynamic Monitoring Circuit
  4. Identify Need for Arterial Line
  5. Set Alarms
  6. Document



Monitor ECG

All CCTC patients have continuous ECG monitoring See ECG Monitoring Standard.


Monitor Cardiovascular System

Monitor invasive BP (Systolic/Diastolic/Mean), PAP (Systolic/ Diastolic/ Mean), HR, RR and SpO2 continuously.  Maintain HR and arterial blood pressure alarms.  

Document Vital Signs Q1H and PRN for all new admissions, for patients with invasive monitoring (arterial lines or pulmonary artery catheters), for patients receiving continuous of medications that influence blood pressure, or patients whose neurological, cardiovascular or respiratory status has varied or is concerning during the previous 24 hours or for patients considered to be at risk for deterioration. Q1H and PRN is the default monitoring frequency.

The minimum frequency for monitoring Vital Signs for patients in CCTC is at the start of the shift and Q4H.  Less frequent monitoring than Q shift may be appropriate for patients who are awaiting a bed on the ward.

Critical Care Nurses will increase the frequency of monitoring for any change in patient condition or where there are concerning findings; an order is not required to increase the frequency but may warrant an order to increase the ongoing frequency if a previously placed order was for less frequent monitoring.

Critical Care Nurses may decrease the frequency of BP monitoring in patients who remain stable without intervention, and who do not meet any of the requirements noted above. When the frequency of monitoring is decreased, the rationale used to support the frequency change must be documented.

Assess Color, Sensation and Movement of extremities distal to intravascular catheters q 1 h. Assess pulses and capillary refill q shift and document in the eHR. Assess pulses and document findings in graphic record q 1-4 for patients with femoral lines, lower limb trauma, vascular surgery or impaired circulation.  

Report all adverse findings or changes to a patient cardiovascular condition to the provider.  Loss of a pulse is a very late finding for patients with compartment syndrome; if there is concern for compartment syndrome (palor, puffiness or swelling, paresthesia/sensory changes or paralysis/motor weakness), notify the provider promptly.  Pain that is disproportionate to that expected for a given injury may indicate muscle necrosis. 

Maintain visibility (minimal linen whenever possible) of arterial line sites for prompt detection of bleeding.

Ensure luer-locked connections on all invasive lines, including the venting stopcock at the transducer (hemorrhage and infection risk if vented cap left in place).


Vasopressors may be administered temporarily via peripheral IV and without placement of an arterial line, but an order to administer peripheral vasopressors and a separate order to defer arterial line placement must be entered in One Chart.  This practice can facilitate faster resolution of shock and improves the safety of line placement by deferral to a more controlled setting.

The intent of peripheral vasopressor and arterial line deferral is also to avoid unnecessary line placement for patients who only require a short course of vasopressor therapy.  Patients will require frequent NIBP activation when running vasoactive drugs to ensure BP is within target range.  Frequent NIBP activation can disrupt sleep and be uncomfortable for patients; activation of the NIBP cuff may transiently increase the blood pressure and can mask a true low reading.

Nurses must be aware of the protocol for peripheral vasopressor administration and the deferral of arterial line placement, and recognize when a central line and arterial line is indicated. Patients who remain unstable, require escalating doses or multiple infusions require central and arterial lines.  

Nurses must also be aware of acceptable IV sites for peripheral vasopressor administration (require a minimum of 2 peripheral IVs in forearm of upper arm including an emergency vasopressor backup, that are 20 gage or higher, should not be administered via the antecubital fossa vessels).

It is essential that nurses assess the site of peripheral vasopressor administration at least Q1H and document findings, as peripheral vasopressors do carry significant risk for harm.  Early detection of potential infiltration or vessel injury before serious harm occurs is an essential critical care nursing requirement.  Assess the site using the LHSC Infiltration and Phlebitis approved scales. 

If an assessment of 1 or higher is identified on either scale, switch the peripheral vasopressors to the backup site and notify the physician.  Do not flush or saline lock the IV site of concern, but leave it in place until assessed by the provider in case phentolamine injection into an interstitial catheter is indicated. Review the decision tree for vasopressor infiltration.

NIBP Versus Arterial Line Pressures

The systolic and diastolic pressures between an NIBP and arterial line catheter should not be expected to match.  If there is a patent arterial catheter with a good quality arterial waveform, and the line is appropriately pressurized, flushed and leveled, the arterial pressure should be the most accurate reading. The systolic pressure of peripheral arterial catheters will usually overestimate the systolic and underestimate the diastolic pressures when compared to the NIBP, but the MAP should compare more closely.

NIBP cuffs do not provide continuous pressure monitoring. Although more accurate than auscultative BP monitoring, NIBP cuffs can become inaccurate when peripheral circulation is compromised. NIBP cuffs are uncomfortable and can produce bruising in susceptible patients; they are not appropriate when >q1h BP monitoring is required. Repetitive inflation of a BP cuff can lead to false readings. NIBP measurements utilize different technology and may produce systolic readings that do not match the arterial line systolic reading. 

If the patient has a good quality arterial catheter, the NIBP should only be assessed at the start of the shift and PRN; do not leave the NIBP cuff on the patient's arm or activate it on an ongoing basis if the arterial pressure is accurate.

Comparison of NIBP and arterial line pressures should always consider:

  • Are you comparing MAPs (and not S/D)?
  • Is the quality of the arterial waveform adequate?
  • Was the arterial transducer correctly leveled and is there an adequate volume and pressure in the flush bag?
  • Was the arterial line pressure taken immediately after the NIBP (and not 5 minutes apart)?
  • Were both pressures measured from the same limb?
  • Could the NIBP reading be influenced by the noxious stimulation associated with cuff activation? Compare the arterial pressure immediately after NIBP activation. 
  • Was the correct sized cuff used for the NIBP measurement and was the arm relaxed and at heart level?
  • Could the variance in MAP values be due to an arrhythmia and variability in beat-to-beat stroke volume?  This is easier to evaluated from a continuous arterial line pressure.

Immediately following arterial line insertion, vasospasm can accentuate the systolic pressure further.  Patients with valvular heart disease or other cardiac disorders can have an extra systolic pulse wave (pulsus bisferiens) on their arterial waveform. Vasospasm may be decreased by wrapping the limb in a warm blanket or with sufficient time post insertion.

DO NOT adjust the filter frequency of the Philip's monitor to alter the displayed pressures - this will lead to a continuous alteration of all subsequent pressures by an equivalent amount until the patient is discharged from the monitor.

Always evaluate the patients blood pressure in the context of their level of consciousness, urine output, heart and respiratory rate changes and lactate/ScvO2).  This is more meaningful that any isolated number and helps to determine the optimal pressures for a given patient.

Change peripheral IVs when there is a concern of potential infection, contamination or for abnormal Infiltration and Phlebitis Scale results. 


Maintain Hemodynamic Circuit

RNs in CCTC are responsible for the priming, zeroing, leveling, and maintenance of hemodynamic pressure monitoring circuits and for the assessment and monitoring of hemodynamic pressures and waveforms.

Ensure that pressurized flush devices are on separate IV poles, 1 meter away from the articulating arms.

Confirm at least 250 mL remaining in saline flush and bags are pressurized to 300 mmHg or higher at the start of each shift, Q4H and with any change in waveforms.

RNs in CCTC may flush hemodynamic monitoring circuits as required to maintain patency.

Select a scale with a defined "0" baseline when monitoring invasive pressure waves continuously (arterial line, continuous right atrial or pulmonary artery waveforms from a right heart catheter). Use of "optimize scale" is not recommended.  Optimize scale will always adjust the peak and trough pressures so that the wave fills the entire waveform space.  When left in optimize scale, the ability to recognize subtle waveform dampening that might prompt earlier interventions for patency loss or the need to repressurize the flush system is lost, which may contribute to premature loss of the arterial line.  It also eliminates the visual assessment of either an increase or decrease in pressure.

Select a scale with a zero baseline that maximizes the pressure waveform size, and revise the scale for significant changes in arterial pressure after assessing and intervening for the waveform change (real or erroneous circuit problem). 


Identify Need for Arterial Pressure Monitoring

Continuous arterial pressure monitoring is indicated for patients requiring BP monitoring >q1h, receiving continuous IV infusion of medications that affect cardiac output/blood pressure, requiring frequent blood gas monitoring, or who are hemodynamically/neurologically unstable.

Arterial lines with continuous MAP monitoring is also required for patients with Intracranial Pressure Monitoring in order to continuously identify Cerebral Perfusion Pressure.

Prior to recording hemodynamic values, evaluate pressure waveforms, verify transducer levels, and ensure that there is at least 250 mL of saline in the flush bag, and the flush bag is adequately pressurized.

See Standard for Arterial Line Monitoring.

Cuff BP measurements become increasing less accurate when hypotension develops. Accuracy is also affected by user technique and cuff size. Insertion of an arterial line is easiest when a patient has an adequate BP. Continuous infusion of vasoactive drugs necessitates continuous BP monitoring to evaluate response to drug therapy and to identify adverse effects (see policy for deferred arterial line placement).

Patients may have differing BPs between left and right limbs, and peripheral circulation may be reduced in shock. Femoral or central arterial catheters may be more accurate in severe shock states.


Set Alarms

alarms must be on for all patients requiring continuous arterial pressure monitoring. Alarm settings should be selected based on the degree of fluctuation in the patient's BP. Upper and lower alarm limits that represent clinically important changes are selected for each individual patient.  

Nursing discretion is used to determine appropriate alarm parameters based on patient stability, variability and risk.

High and low alarm settings must be assessed Q1H and confirmation documented at the start of each shift and Q4H when invasive monitoring is in use.

Alarms may need to be disabled if an arterial line becomes positional. If an arterial line alarms is disabled, document in the Device Band of the EHR is required. Documentation should include the reason for disabling the alarm and should describe troubleshooting strategies.



Record S/D and M BP in IView in the vital signs section of the eHR. Record the actual mean calculated by the Philip's monitor.

Nurse creates a Dynamic Group under Adult Lines-Devices Band for each peripheral, arterial and central line that includes the insertion site and catheter size.

If the line is inserted by someone other than the nurse who creates the Dynamic Group, document the name of the inserter. To capture the insertion date and time under the Activity field, select inserted.

Document each assessment of site, patency, CSM, dressing appearance and waveform quality at the start of each shift and Q4H PRN in the Dynamic Group. 

Document the Infiltration and Phlebitis Scales Q1H and PRN when peripheral vasopressors or vesicants (such as Dextrose > 12%, electrolyte boluses, bicarbonate, hypertonic saline or mannitol) are administered.

Document abnormal vascular findings in the assess/reassess section of the Dynamic Group. Change peripheral IVs when there is a concern and notify provider for lines that cannot be resolved by the nurse.

Print a waveform at the start of each shift and PRN to record line placement and to confirm waveform quality for all invasive lines.  Post this to the paper-based portion of the health record.

Document reasons for turning the alarms off along with troubleshooting steps attempted to maintain "alarms on" in the Assess/Reassess section of the line specific Dynamic Group or Vital Signs section (for HR alarms).

Document dressing changes in the line specific Dynamic Group and record abnormal findings in the assess/reassess section.

Document deferral of an arterial line and peripheral vasopressors administration in the eHR in the assess/reassess section of the Dynamic Group. Ensure there is an order for both protocol variances and review the ongoing practice with the Consultant/Senior Resident every 12 hours.  Document the discussion in the Multi-Disciplinary Teams record.

Document assessment of site and CSM following arterial line removal at the time the pressure is released, 15 minutes later, then Q 30 minutes X 2, then Q 1 H X 4.

Document any abnormal cardiovascular findings in the assess/reassess section and notify provider.

Document that the date/time that the line was discontinued in the Activity field, then inactivate the Dynamic Group. 

Communicate the recent line removal or any CVS concerns during shift-to-shift report. Include this information in the documented Transfer of Accountability.

Last Updated: February 8, 2023 (BM)