HAMILTON-T1 for ventilator-assisted preoxygenation

Article

Author: Clinical Experts Group, Hamilton Medical

Date of first publication: 05.11.2018

Last change: 05.11.2018

Psupport changed to Pinsp; addition of two screenshots

The use of rapid sequence intubation (RSI) in the Emergency Department is often associated with complications, including serious oxygen desaturation.

HAMILTON-T1 for ventilator-assisted preoxygenation

HAMILTON-T1 and VAPOX technique

The use of CPAP and/or NIV for preoxygenation may be particularly effective in reducing the risk of hypoxemia during intubation. A recent study from Australia now describes use of the HAMILTON-T1 to apply a combination of NIV and pressure-controlled ventilation in high-risk patients (Grant S, Khan F, Keijzers G, Shirran M, Marneros L. Ventilator-assisted preoxygenation: Protocol for combining non-invasive ventilation and apnoeic oxygenation using a portable ventilator. Emerg Med Australas. 2016;28(1):67-72. doi:10.1111/1742-6723.125241).

The authors' VAPOX technique (ventilator-assisted preoxygenation) is made possible by the HAMILTON-T1’s biphasic design and open valve system, which enable the application of NIV for preoxygenation followed by mechanical ventilation after intubation, all with the same breathing circuit.

HAMILTON-T1 settings for VAPOX

After completing the preop tests and connecting the oxygen and power supplies, the HAMILTON-T1 is set up in NIV-ST mode with the following settings:

RR: 6–8 breaths/min
Pinsp: 10 cmH2O
PEEP: 5 cmH2O
Oxygen: 100%
ETS (expiratory trigger sensitivity): 50%
Inspiratory flow trigger: 2 l/min
Ti: 2 s
P-ramp: 50 ms

A nasal cannula is applied to the patient with an oxygen flow rate of 15 l/min and then a face mask is applied. The ventilator is started and preoxygenation applied for 3 minutes.

As soon as apnea ensues, the ventilator transitions to PCV+.

Intubation starts after at least 45 sec, with nasal oxygenation continuing until the ETT is in place.

With the tube successfully positioned, the ventilator can be switched to a conventional ventilation mode.

Basic settings window on HAMILTON-T1 — HAMILTON-T1 Basic settings window

More settings window on HAMILTON-T1 — HAMILTON-T1 More settings window

Results with VAPOX

In this series of patients, there was no occurrence of hypoxia. The two patients with the lowest oxygen saturation at the outset (77% and 79%) increased to 100% and 94% post VAPOX, respectively, with values post intubation at 93% and 92%, respectively. These results showed VAPOX to be both safe and effective.

Using the HAMILTON-T1, this promising technique can successfully be applied to minimize hypoxemia during RSI.

Relevant devices: HAMILTON-T1

313-9075_BiTrac_NIV-circuit_Bilevel-CPAP-application_Adult_SU

BiTrac NIV circuit with filter for Bilevel/CPAP application

BiTrac™ NIV Full Face, Adult Small, Fixed Standard Elbow

Tube for pneumatic nebulizer

Footnotes

References

1. Grant S, Khan F, Keijzers G, Shirran M, Marneros L. Ventilator-assisted preoxygenation: Protocol for combining non-invasive ventilation and apnoeic oxygenation using a portable ventilator. Emerg Med Australas. 2016;28(1):67-72. doi:10.1111/1742-6723.12524

Ventilator-assisted preoxygenation: Protocol for combining non-invasive ventilation and apnoeic oxygenation using a portable ventilator.

Grant S, Khan F, Keijzers G, Shirran M, Marneros L. Ventilator-assisted preoxygenation: Protocol for combining non-invasive ventilation and apnoeic oxygenation using a portable ventilator. Emerg Med Australas. 2016;28(1):67-72. doi:10.1111/1742-6723.12524

Link to article

OBJECTIVE

To describe a simple protocol for ventilator-assisted preoxygenation (VAPOX) prior to rapid sequence intubation in the ED using a Hamilton T1 ventilator in an effort to further reduce the incidence of transient and critical hypoxaemia.

METHODS

Ventilator-assisted preoxygenation includes the following steps; preparation for rapid sequence intubation as per institutional protocols, including departmental checklists. Hamilton T1 ventilator is setup in non-invasive spontaneous/timed mode with settings as described. The patient is optimally positioned and nasal cannula applied with an oxygen flow rate of 15 L/min. A face mask is applied with the jaw pulled forward using a two-handed thenar eminence grip and the ventilator is started. Preoxygenation occurs for 3 min. Drugs including neuromuscular blockers are administered, while the operator ensures the airway remains patent. The ventilator transitions into Pressure Controlled Ventilation once apnoea ensues. Nasal oxygen continues until endotracheal tube is successfully secured.

RESULTS

We describe a case series of the first eight consecutive adult patients on who VAPOX was applied. All eight patients were clinically deemed at high risk of oxygen desaturation. No clinically significant hypoxia occurred, and the lowest oxyhaemoglobin desaturation was 92%.

CONCLUSION

Preoxygenation using a ventilator with an open valve system may allow safe combination of non-invasive ventilation, pressure controlled ventilation and apnoeic oxygenation using nasal cannula. VAPOX may be the technique of choice to preoxygenate and apnoeic oxygenate many patients who undergo rapid sequence intubation in the ED equipped with these ventilators.