Description of Modes Available

All modes are listed.  Comparisons are made between  this ventilator's modes and the
ventilators we study in class. (Differences and similarities highlighted). Unique modes
are described well
nCPAP
nCPAP-PC

Volume-targeted (adaptive pressure control)

APVcmv/ (S)CMV+
APVsimv/ SIMV+ mode
Volume Support (VS)

Minimum insp pressure (Ppeak – PEEP) in VS, APVcmv APVsimv is 5cmH2o

Volume modes are delivered by an adaptive volume controller (adaptive with changes
in lung characteristics)…. The adaptive volume controller works by comparing the userset
tidal volume with the average of delivered and exhaled tidal volumes. The controller in turn
adjusts the inspiratory pressure that will be applied during the next breath in order to obtain
the target volume. The inspiratory pressure is adjusted in steps, to a maximum of 2 cmH2O per
breath. The ventilator recalculates the minimal inspiratory pressure needed to achieve the
target volume as lung characteristics change. This continuous reassessment of the patient’s
dynamic lung status helps guarantee the required ventilation while preventing hypoventilation
or barotrauma.

In the modes (S)CMV+ and PCV+, a spontaneous effort of the patient activating the flow trigger,
results in a pressure controlled and time cycled breath.

Breaths can be patient (flow) triggered in all modes except nCPAP and nCPAP-PC, based on an
operatorset flow sensitivity

An operator-set pressure ramp (P-ramp) defines the time required for inspiratory pressure to
rise to the set (target) pressure.

APVcmv: adaptive pressure ventilation with controlled mandatory ventilation

Also known as (S)CMV+ (synchronized controlled mandatory ventilation)
(time-cycled mandatory breaths)

volume targeted, pressure controlled (pressure adjusted breath to breath

to achieve target VT)
will deliver the target VT at the lowest possible pressure (depending on
lung conditions)
ventilator or patient trigger (patient can trigger above set rate)
(mandatory breath)

Pressure will be limited according to the set Plimit/high pressure alarm

Inspiratory pressure will not exceed 10cmH2O below the set Plimit

(assist/control type mode)

APVsimv/ SIMV+: adaptive pressure ventilation w synchronized intermittent
mandatory ventilation
Aka synchronized intermittent mandatory ventilation plus
(volume-targeted mandatory breaths using the lowest pressure)

volume-targeted, time-cycled mandatory breaths and pressure-supported, flow-cycled

spontaneous breaths

Mandatory breaths – volume targeted (set rate)

 VT target
 Rate
 I:E

Spontaneous breaths – pressure supported (pt triggered)

 Delta P (psupp above PEEP)

 ETS
 Tmand, Tspont
 TImax

High pressure boundary is Plimit – 10 cmH2O for inspiratory pressure

Exception is sigh breaths which can come within 3 cmH2O below Plimit

Tmand (mandatory time) -> patient triggers during this period,

mandatory breath is delivered
Tspont (spontaneous time) -> patient triggers breath during this period,
vent delivers a spontaneous pressure-supported breath
(if patient doesn’t trigger a breath during Tspont, mandatory breath will
be delivered at the end of Tmand)

(assisted, controlled, spontaneous)

Volume Support (VS): pure spontaneous mode

volume-targeted (pressure adjusted b/w breaths to achieve
target volume)

decreases support when patient’s effort increases

increases support when patient’s effort decreases

trigger: patient
The biphasic concept It is widely accepted that early spontaneous breathing is beneficial for
many ventilated patients, provided the device lets the patient inspire and exhale whenever the
respiratory muscles contract and relax. In other words, the ventilator needs to be in synchrony
with the patient’s muscle contractions, regardless of how the ventilator’s controls are set.
Accordingly, the HAMILTON-T1’s pneumatics were designed to permit the patient’s free
spontaneous breathing. The ventilator never forces the patient into a preset breathing pattern
but always yields to spontaneous breathing. This is achieved through a special valve control
system independent of any trigger mechanism. This concept is called “biphasic,” because gas
can flow into and out of the patient at any time. The biphasic concept applies in all HAMILTON-
T1 ventilation modes. Implementation of the biphasic concept improves patient breathing
comfort1, as spontaneous breathing is encouraged2, less sedation is required even with
prolonged inspiratory phases3, and there is a free delivery of flow to the patient at any time.
The decelerating inspiratory waveform improves gas distribution, oxygenation, and lowers peak
pressures 2,3,4,5,6. Figures B-1 through B-3 illustrate this concept. Figure B-1 shows a passive
patient ventilated by pressure-controlled ventilation. Gas flows into the patient when pressure
rises and gas flows out of the patient when inspiratory pressure falls.

Mandatory breaths. See Table B-1 for information on mandatory breaths as they apply to the
various modes. Not listed in the table are operator-initiated mandatory (manual) breaths,
which are pressure controlled and time cycled. Mandatory breaths have a decelerating flow
waveform. • Spontaneous breaths. Spontaneous breathing is allowed in all modes at any time.
Additionally, in PSIMV+, SPONT, SIMV+, NIV, NIV-ST, and DuoPAP, spontaneous breaths are
pressure supported and time cycled if the users set flow trigger threshold is passed. In the
modes (S)CMV+ and PCV+, a spontaneous effort of the patient activating the flow trigger,
results in a pressure controlled and time cycled breath. • Triggering. Breaths can be patient
(flow) triggered in all modes except nCPAP and nCPAP-PC, based on an operatorset flow
sensitivity. All modes permit operator-initiated manual breaths. • Pressure. A positive baseline
pressure (PEEP/CPAP) may be set for all breaths in all modes. • Pressure rise time. An operator-
set pressure ramp (P-ramp) defines the time required for inspiratory pressure to rise to the set
(target) pressure. • FiO2. FiO2 can be set in all modes except when oxygen is provided by a low-
pressure supply.

Pressure-Controlled modes
PCV + mode
PSIMV+ mode
PSIMV+ mode with PSync
DuoPAP
APRV
SPONT

PCV+: mandatory
Pressure controlled (delta P/pressure above PEEP)
Rate and I:E
Pramp
 (this mode can be used with a speaking valve)

PSIMV+: pressure controlled SIMV

With or without PSync
(without) mandatory breaths – PCV +
Tmand, and Tspont
Tmand (mandatory time) -> patient triggers during this period,
mandatory breath is delivered
Tspont (spontaneous time) -> patient triggers breath during this period,
vent delivers a spontaneous pressure-supported breath
(if patient doesn’t trigger a breath during Tspont, mandatory breath will
be delivered at the end of Tmand)
Each SIMV breath interval includes mandatory time (Tmand) and spontaneous time (Tspont)
portions (Figure B-16). During Tmand, the ventilator waits for the patient to trigger a breath.
When the patient triggers a breath, the ventilator immediately delivers a mandatory breath. If
the patient does not trigger a breath, the ventilator automatically delivers a mandatory breath
at the end of Tmand. After the mandatory breath is delivered, the patient is free to take any
number of spontaneous breaths for the remainder of the SIMV breath interval.

Delta P set for mandatory breaths

Rate and I:E define timing of breath cycle
Delta P set for PS in spont breaths

(w PSync) IntelliSync is an additional setting to apply the same pressures for

spontaneous and controlled breaths. It allows patients to breath spontaneously when they are
able to maintain the operator-set guaranteed rate.

DuoPAP: ventilator switches automatically and regularly between two operator-selected

levels of positive airway pressure or CPAP. The patient may breathe freely
at either level. In DuoPAP pressure support can be added to these spontaneous
breaths. Cycling between the levels is triggered by DuoPAP timing settings or by patient
effort.

pressure settings Phigh and PEEP/CPAP and time settings Thigh and Rate
Pressure support can be set to assist spontaneous breaths in DuoPAP, whether they
occur at the PEEP/CPAP or Phigh level. Psupport is set relative to PEEP/CPAP the target
pressure becomes PEEP/CPAP. That means that spontaneous breaths at the Phigh level
are supported only when this target pressure is greater than Phigh

APRV: pressure-controlled inverse ratio ventilation

Allows spont breathing at any time
Phigh Plow, Thigh, Tlow
SAFETY MODE:
The blower runs constantly to create inspiratory pressure (Pinsp) (Table B-3). The expiratory
valve switches system pressure levels between PEEP and inspiratory pressure. Patient sensing is
nonfunctional during safety ventilation. You must switch off ventilator power to exit safety
ventilation. If the technical fault alarm is serious enough to possibly compromise safe
ventilation, the ventilator enters the ambient state. The inspiratory channel and expiratory
valves are opened, letting the patient breathe room air unassisted. You must switch off
ventilator power to exit the ambient state.

SPONT: PS set to zero, functions like CPAP

Intelligent

ASV: modernized MMV

Maintains an operator-preset minimum minute ventilation (independent
of patients activity)
Will adjust VT (insp pressure) and rate to deliver a breathing pattern
which results in the least WOB with a lung-protective strategy

Once ASV is started, the HAMILTON-T1 calculates an optimal breath pattern and
associated target values for tidal volume and rate according to the rules
in ASV, then adjusts the inspiratory pressure (Pinsp) and machine rate
(fControl) to achieve the targets.
Otis’ equation

Pressure High Pressure alarm limit, in cmH20

Patient height Patient height, in cm or inches
Gender Sex of patient
%MinVol Desired minute ventilation, in % of normal values
Automatically adjusts for changing patient conditions between active and passive states •
Mandatory breaths are pressure controlled • Spontaneous breaths are pressure supported •
Prevents tachypnea • Prevents AutoPEEP • Prevents dead space ventilation • Does not exceed
a ΔPinsp pressure of 10 cmH2O below the upper pressure limit

ASV interacts with the patient continuously. Whenever the patient’s respiratory mechanics
change, ASV adapts to this change. Whenever the patient’s breathing activity changes, ASV
adapts. To let you view the current status, the HAMILTONT1 provides the ASV target graphics
(ASV Graph) window (Figure C-5). To monitor progress over time, it is recommended that you
plot trends for Pinsp, fTotal, and fSpont. Interpret these trends, together with the %MinVol
setting. Tables C-2 through C-4 provide interpretation of typical ventilatory patterns.
all this without exceeding a plateau pressure of 10 cmH2O below the upper pressure limit.
INTELLiVENT-ASV: INTELLiVENT-ASV is an advanced ventilation mode, based on the proven
Adaptive Support Ventilation (ASV) mode, to automatically regulate CO2 elimination and
oxygenation for both passive and active patients, based on both physiologic data from the
patient and clinician-set targets. With this mode, the clinician sets targets for PetCO2 and SpO2
for the patient. INTELLiVENT-ASV then automates management of the controls for CO2
elimination (%MinVol), and oxygenation (PEEP and Oxygen) based on these targets and on the
physiologic input from the patient (PetCO2 and SpO2). INTELLiVENT-ASV continuously monitors
patient conditions and automatically and safely adjusts parameters to keep the patient within
target ranges, with minimal clinician interac

NIV
NIV-ST
nCPAP
high-flow

Hamilton T1 is that it pressure limits a breath 10 cmH2O below the set pressure alarm e.g. with a pressure
alarm set at 40cmH2O, the delivered breath will be limited to a maximum pressure of 30cmH2O.