When the low pressure alarm on the ventilator sounds it indicates which of the following?

Any alarm that sounds from the HAMILTON-C3 indicates that there is a problem. During the ventilator’s start up, it does an alarm check to ensure that they are functioning properly. These are all adjustable alarms with ranges that can be set depending on the patient.

The maximum time allowed from the beginning of one inspiration to the beginning of the next inspiration. If the patient does not trigger a breath during this time, an alarm sounds. Apnea backup ventilation will begin, if enabled. (The Apnea alarm can be turned off). Take these steps:

• Check the patient’s condition
• Check trigger sensitivity
• Consider a mandatory breather

Low and high expiratory minute volume. If either is reached, the alarm will sound. For a low ExpMinVol alarm, take the following steps:

• Check the patient's condition
• Check the breathing circuit and artificial airway of the patient for leaks and/or disconnection
• Check and confirm settings, including alarms
• Check the %MinVol and Pat. height settings

For a high ExpMinVol alarms, take the following steps:

• Check the patient's condition
• Check and confirm settings including alarms

Low and high monitored total breath rate (fTotal), including both spontaneous and mandatory breaths. If either limit is reached, a medium-priority alarm will sound. For a low fTotal alarm, take the following steps:

• Check the patient's condition
• Adjust the low fTotal alarm limit
• Check the %MinVol and Pat. height settings

For a high fTotal alarm, take the following steps:

• Check the patient for adequate ventilation (VTE)
•  Check alarm limits
• Check the trigger sensitivity
• If the ventilator is in ASV mode, refer to the ASV appendix in the Operator’s Manual

Low and high monitored oxygen concentration. If either limit is reached, a high-priority alarm will sound. This is only applicable if low-pressure oxygen is used. For a low oxygen alarm, take the following steps:

• Check the patient’s condition
• Check the oxygen supply. Provide an alternative source of oxygen, if necessary
• Calibrate the oxygen cell
• Provide alternative ventilation and install a new oxygen cell

For a high oxygen alarm, take the following steps:

• Calibrate the oxygen cell
• Install a new oxygen cell
• Check alarm limits

Low and high monitored Pet-CO2. If either limit is reached, a medium-priority alarm will sound. For a low Pet-CO2 alarm, take the following steps:

• Check the patient’s condition
• Check the breathing circuit and flow sensor/artificial airway of the patient for leaks
• Check and confirm settings including alarms

For a high Pet-CO2 alarm, take the following steps:

• Check the patient’s condition
• Check and confirm the settings including the alarms

Low and high monitored pressure at the patient’s airway (Ppeak). If high pressure is reached, or low pressure is not reached, a high-priority alarm will sound. In addition, when high pressure reaches 10 cmH20 pressure is limited: no further pressure is applied. If high pressure is reached, the ventilator immediately stops gas flow to the patient and opens the expiratory valve to reduce pressure to the PEEP/CPAP level. The HAMILTON-C3 is designed to limit patient airway pressure to 60 cmH2O, but if pressure climbs to 75 cmH2O, the ambient valve opens, releasing pressure to the ambient level. For a low pressure alarm, take the following steps:

• Check the patient’s condition
• Check the breathing circuit for a disconnection between the patient and the flow sensor, or for other large leaks

For a high pressure alarm, take the following steps:

• Check the patient’s condition
• Adjust the pressure alarm limit
• Check the artificial airway of the patient for kinks and occlusions
• Check the breathing circuit and flow sensor tubes for kinks and occlusions
• Provide alternative ventilation once the ventilator enters the ambient state

If the alarm persists, make sure the pressure limit is high enough so that sufficient pressure can be applied for adequate breath delivery.

Low and high expiratory tidal volume, for two consecutive breaths. If either limit is reached, a medium-priority alarm sounds. When the delivered Vt is greater than 1.5 times the set Vt high alarm, the Inspiratory volume limitation alarm is generated. In this case, the device aborts the breath and reduces the pressure to PEEP level. The APV controls reduce the pressure for the next breath by 3 cmH20. For a low Vt warning, take the following steps:

• Check the patient’s condition
• Check and confirm settings (including alarms)
• Check the breathing circuit and artificial airway of the patient for leaks and/or a disconnection
• If the ventilator is in ASV, check for a kinked ET tube

For a high Vt warning, take the following steps:

• Check the pressure and volume settings for potential leaks and/or disconnections
• Check and confirm settings including alarms

Alarms or observations that indicate power failure from either the battery or the external power source. If both power sources are functional, it is unlikely that the ventilator will turn off suddenly and unexpectedly.

These alarms (Table 8-2, Page 159) indicate the battery is not working properly. Connect to an external power source. Check to see if the battery is intact and connected. If not, replace the battery using this guide [In Progress].

An alarm should sound signaling the loss of external power (Table 8-2, Page 167). Check the connection to the external power source. To prevent unintentional disconnection of the power cord, make sure it is well seated into the ventilator socket and secured with the power cord retaining clip.

When connected to AC, there should be a frame around the AC symbol in the bottom right corner of the monitor.

If the disconnection from external power source alarm is a result of the external power failing, the ventilator will begin running on its own battery. Make sure the battery is functional and have secondary batteries on hand if needed. It is recommended that the ventilator’s batteries be fully charged before ventilating a patient in case of an external power source failure.

It is important for the safety of the patient that the ventilator is in the appropriate setting and mode depending on the patient’s age, size, and condition. There are some considerations to take into account before adjusting.

The HAMILTON-C3 has initial conditions for each of these two categories, but it is important to make the distinction if your patient is an adult/ pediatric, or a neonatal. The initial settings for an adult/ pediatric have the option of male or female, height from 30cm to 250cm, and IBW from 3kg to 139kg. The initial settings for an neonatal have the weight set from 0.2kg to 30kg.

If you have not already done so, select the PreOp check button and perform the required tests.

Select the desired patient group: Adult/ Pediatric, Neonatal, or Last Patient (which refers to the patient who was previously using this specific ventilator).

Adjusting settings as follows:

• For adult and pediatric patients, select the Gender and specify the patient height, The ideal body weight (IBW) is automatically calculated and dis- played.
• For neonatal patients, adjust the weight setting. For these patients, the system uses body weight and does not calculate IBW.
• To start ventilating the patient, press “Start Ventilation” on the touchscreen.

To start ventilating the patient, press “Start Ventilation” on the touchscreen.

Open Controls > Basic window

Select a parameter and adjust the value. The change takes effect immediately. Repeat for any other desired parameters.

Touch the “More” tab on the touchscreen to open the Controls > More window and select and adjust parameters as desired.

If applicable, touch the “Apnea” tab to open Controls> Apnea window. Select or deselect “Backup” as required.

If applicable, touch the “TRC” tab on the touchscreen to open Controls > TRC window and select and adjust parameters as desired.

If applicable, touch the “Patient” tab on the touchscreen to open Controls > Patient window and review/adjust the patient height and gender. The “Patient” tab is only available in the Controls window during active ventilation. During standby, the patient controls are greyed out in the Standby window and accessible in the patient tab if “Last Patient setup” is selected.

The ventilator display is showing data that seems to be or is clearly incorrect. A video guide of how to perform the tightness test, flow sensor calibration, CO2 sensor calibration, and O2 sensor calibration can be found here.

Inaccurate readings may be a result of leaking occurring from the breathing circuit. The first thing to try is performing the tightness test to check for leakage in the patient breathing circuit (Section 3.3.2.1, Page 67). Make sure another source of ventilatory support is available during this test. The patient must be disconnected from the ventilator during the test.

Set the ventilator up as for normal ventilation, complete with the breathing circuit.

Touch the System button in the lower right corner and then the Tests & calib tab. To run the tighness test, touch the Tightness button in the upper left of the Tests & calib tab screen (to cancel the tightness test while it is in progress, touch the Tightness button again). The text Disconnect patient should now be displayed.

Disconnect the breathing circuit at the patient side of the flow sensor. Do not block the open end of the flow sensor. The text Tighten patient system should now be displayed.

Now block the opening (wearing a sterilized glove is recommended).

The text Connect patient should now be displayed.

Connect the patient. When the test is complete, verify that there is a green checkmark in the Tightness checkbox. If the test fails, see the section titled Leaking From Breathing Circuit for more troubleshooting options.

Inaccurate readings may be caused by an improperly calibrated flow sensor. Calibrate the flow sensor after connecting a new flow sensor or whenever the Flow sensor calibration needed alarm appears in order to ensure accurate readings or identify a faulty flow sensor. To check and reset the calibration points specific to the flow sensor in use, run the flow sensor calibration. Make sure another source of ventilatory support is available during this calibration. The patient must be disconnected from the ventilator during the test. If there is a mismatch between the active patient profile and the flow sensor type you are using, the calibration fails. Ensure you are using the correct flow sensor for the patient (ex. adult/pediatric flow sensor or neonatal flow sensor). For more information on how to configure patient profiles, change between patient groups, and switch between modes, see the above section titled Ventilator Is In The Wrong Mode.

• To calibrate an adult/pediatric flow sensor (Section 3.3.2.2, Page 68):

Set the ventilator up as for normal ventilation, complete with breathing circuit and flow sensor.

Touch the System button in the lower right corner and then the Tests & calib tab. To run the flow sensor calibration, touch the Flow sensor button on the left-hand side of the Tests & calib tab screen (to cancel the flow sensor calibration while it is in progress, touch the Flow sensor button again). If you have not already disconnected the patient, the message line will display Disconnect patient.

Disconnect the breathing circuit at the patient side of the flow sensor.

Follow the instructions displayed in the message line. When the message line displays Turn flow sensor, attach the adapter (if needed) and turn the flow sensor around as indicated below.

Note: If you are using the disposable flow sensor PN 281637, the additional adapter for calibration must be attached.

Wait. The message line should display Maneuver in progress. When the message line displays Turn flow sensor again, turn the flow sensor back to its starting position and disconnect the adapter (if it was needed).

When calibration is complete, verify that there is a green check mark in the Flow sensor checkbox. If the flow sensor calibration fails, see the subsection titled Flow Sensor Calibration Fails within the section below titled Leaking From Breathing Circuit for more troubleshooting options.

• To calibrate a neonatal flow sensor (Section 5.2.4.1, Page 114):

During calibration, the flow sensor is always placed after the Y-piece, regardless of which ventilator mode is selected. If you are using the nCPAP-PS mode, where the flow sensor is connected directly to the expiratory valve during ventilation, be sure to calibrate the flow sensor with it at the patient end of the breathing circuit, after the Y-piece.

Set up the ventilator for normal ventilation, complete with the breathing circuit and expiratory membrane and cover.

Make sure the Neonatal patient group is selected. See the section above titled Ventilator Is In The Wrong Mode for information on how to change between patient groups and modes and configure patient profiles. Make sure a neonatal-pediatric flow sensor is installed at the patient end of the breathing circuit and the calibration adapter is available.

Touch the System button in the lower right corner and then the Tests & calib tab. To run the flow sensor calibration, touch the Flow sensor button on the left-hand side of the Tests & calib tab screen (to cancel the flow sensor calibration while it is in progress, touch the Flow sensor button again). If you have not already disconnected the patient, the message line will display Disconnect patient.

Disconnect the breathing circuit at the patient side of the flow sensor.

Follow the instructions displayed in the message line. Attach the calibration adapter to the patient end of the flow sensor as shown below.

When prompted, turn the flow sensor around as indicated below and attach the calibration end to the Y-piece.

When prompted to turn the flow sensor again, remove the calibration adapter, and turn the flow sensor back to its starting position.

When calibration is complete, verify that there is a green checkmark in the Flow sensor checkbox. If the flow sensor calibration fails, see the subsection titled Flow Sensor Calibration Fails within the section below titled Leaking From Breathing Circuit for more troubleshooting options.

Erroneous data may be a result of an improperly calibrated or faulty O2 cell. Calibrate the O2 cell to ensure accurate readings or identify a faulty O2 cell (Section 3.3.2.3, Page 69). The oxygen cell calibration requires that the ventilator’s oxygen monitoring be enabled and there must be an oxygen cell in the device. See the repair manual titled [In Progress] for help locating the oxygen cell. To determine whether oxygen monitoring is enabled, touch the System button in the lower right corner and then the Sensors tab and ensure the O2 cell checkbox is selected. If you are using the low-pressure-mode, disconnect all O2 supplies during calibration. After reconnecting, the oxygen concentration is set to 21%. The O2 cell requires approximately 30 minutes warm-up time to reach stable values. O2 monitoring during this time period may be more variable so it is recommend to perform the calibration after the O2 cell is warmed up. Note: When the neonatal patient group is selected, the ventilator must be in Standby to perform the O2 cell calibration.

It is recommended to calibrate the O2 cell using 100% oxygen to improve the stability of measurements at higher oxygen concentrations. To calibrate at 100% oxygen, adjust the settings on the ventilator using the information provided in Table 3-5 below to choose the associated settings and connections for calibration.

Touch the System button in the lower right corner and then the Tests & calib tab. To run the oxygen cell calibration, touch the O2 cell button on the left-hand side of the Tests & calib tab screen.

When the calibration is complete, verify that there is a green check mark in the O2 cell checkbox. If the calibration fails, try the following options, repeating the calibration after each one until it is successful:

1. Ensure the O2 cell is connected and a Hamilton Medical O2 cell (PN 396200) is used.
2. Replace the O2 cell using this guide [In Progress].

Erroneous data may be a result of an improperly calibrated or faulty CO2 sensor/adapter if you are using the optional mainstream CO2 sensor or sidestream CO2 sensor. When running the CO2 sensor/adapter calibration (Section 3.3.2.4, Page 70), always have the sensor attached to the airway adapter and wait at least 20 seconds, or 2 minutes for best results, to perform the calibration after removing the adapter from the patient’s airway. This time allows any CO2 remaining in the adapter to dissipate.

Before running the calibration, make sure the CO2 hardware option is installed and activated and that CO2 monitoring is enabled. To determine whether CO2 monitoring is enabled, touch the System button in the lower right corner and then the Sensors tab and ensure the CO2 checkbox is selected. Once enabled, the sensor requires approximately 90 seconds to warm up.

Disconnect the CO2 sensor from the breathing circuit. Attach the airway adapter to the sensor as indicated in Figure 2-10 for the mainstream CO2 sensor,

or in Figure 2-12 for the sidestream CO2 sensor.

Place the sensor/adapter away from all sources of CO2 (including the patient’s and your own exhaled breath) and the exhaust port of the expiratory valve.

Connect the sensor cable to the CO2 connection on the ventilator (the item labeled (1) in Figure 2-12).

Touch the System button in the lower right corner and then the Tests & calib tab. To run the CO2 sensor/adapter calibration, touch the CO2 button on the left-hand side of the Tests & calib tab screen. Do not move the sensor during calibration.

When the calibration is complete, verify that there is a green check mark in the CO2 checkbox. If the calibration fails, try the following options, repeating the calibration after each one until it is successful:

1. Check airway adapter and clean if necessary.
2. Ensure there is no source of CO2 near the airway adapter.
3. Connect a new airway adapter.
4. Install a new CO2 sensor.

Monitored parameters, alarms, or observations indicate air leaking from the breathing circuit. The following alarms may indicate a leak: Loss of PEEP, Low pressure, Low minute volume, Oxygen supply low, Pet-CO2 low, Vt high/low (Table 8-2, Page 169).

Check if there is displacement of the nasal or combined nasal-oral cannulas. An alarm signaling Pet-CO2 will sound when the lower limit is passed (Section 2.6.2.1, Page 52). To replace or repair these sensors, see the repair guide [In Progress].

Check the breathing circuit for a disconnection between the ventilator and the flow sensor and make sure that the flow sensor and expiratory valve/membrane are properly seated. If the calibration fails again, replace the flow sensor and valve/membrane. To replace or repair these sensors, see the sensor repair guide [In Progress].

Leakage may be more significant because the neonatal ET tubes do not have a cuff. During a leak, Inspiratory tidal volume (VTI) can be much greater than the measured expiratory tidal volume (VTE).

Due to the leakage at the patient interface, displayed exhaled volumes in the noninvasive modes can be substantially smaller than the delivered volumes. These values do not account for leakage between the ventilator and flow sensor. Make sure that the oxygen cell is installed at all times even when oxygen monitoring is disabled. Replace or repair the oxygen cell using this guide [In Progress]. Check the subsection titled Leaking From Breathing Circuit under the above section titled Sensors Displaying Erroneous Data for directions on how to perform the tightness test to check for leakages in the breathing circuit.

This sort of leakage is alright because the open breathing circuit permits air to leak around the mask or through the mouth. The ventilator will maintain the prescribed pressure by adjusting the inspiratory flow.

What does low pressure mean on a ventilator?

What should the respiratory therapist check first when a low pressure alarm is activated on a ventilator?

When the high pressure alarm on the mechanical ventilator alarm sounds the nurse starts to check for the cause which condition triggers the high pressure alarm?

Which is a potential complication of a low pressure in the endotracheal tube cuff?