Getting the Hang of the Hamilton Ventilator

Overview of the Hamilton T1 Ventilator

• Weight: 7kg
• Battery life: Up to 9 hours
• Tidal volume range: 2ml to 2000ml
  • Suitable for all patients, from neonates to bariatric patients
• PEEP settings: 0 to 35 cmH2O
• Inspiratory flow rate: Up to 260 L/min
• FiO2 setting range: 21% to 100%
• Features:
  • Intelligent NIV
  • Integrated nebuliser and high flow options
  • Fully disposable circuits
  • Can operate without compressed air
• Daily checks: Automatic test for tightness, flow sensor, and oxygen cell

Common Ventilation Modes

S-CMV: Synchronised Continuous Mandatory Ventilation

• Pressure-regulated volume-controlled mode
• Steps:
  • Power on
  • Complete daily checks
  • Select patient parameters (adult/pediatric, height, and gender)
  • Adjust RR, I:E, Vt, PEEP, and FiO2
  • Adjust alarm limits as necessary

SIMV: Synchronized Intermittent Mandatory Ventilation

• Volume-controlled mode

Non-Invasive Ventilation (NIV)

• Modes: CPAP, BPAP, NIV, ST-NIV
• Steps:
  • Power on and complete daily checks
  • Select mode and patient parameters
  • Adjust PEEP and alarm limits as required
• CPAP: Set PEEP (EPAP) to desired level
• BPAP: Set PEEP and additional pressure (pInsp) to create IPAP
• Monitor % leak to manage oxygen needs

Alarm Patterns and Meanings

High Priority

• Indicators: Red light and 5 beeps
• Issues: Apnea, minute ventilation, circuit disconnection, oxygen failure

Medium Priority

• Indicators: Yellow light and 3 beeps
• Issues: Pressure limitation, Vt, or PEEP issues

Low Priority

• Indicators: Yellow light and 2 beeps
• Issue: External power loss

Minute Ventilation Alarms

• Calculation: Tidal volume x respiratory rate
• High MVe Alarm: Hyperventilation indicated, adjust TV or RR
• Low MVe Alarm: Check for circuit leak or disconnection

Other Alarms

• pMAX: Default to 35, alarm at pMax-10
• PEEP Alarm: High PEEP indicates elasticity issues like pneumothorax
• Low/High Vt: Monitor for atelectasis or barotrauma

Additional Features and Tips

• Oxygen Consumption Monitoring: Check system tab for l/min usage
• Auto Adjusting Alarms: Use "Auto" button to set limits
• I:E Ratio: Balance inspiration and expiration time
• ASV (Adaptive Support Ventilation):
  • Maintains set MVe with optimal tidal volume and RR
  • Best used in ICU settings

Specific Clinical Settings

ARDS

• Strategies: Controlled oxygen exposure, low tidal volumes (4-6 ml/kg), adequate PEEP, peak pressure <30 cmH2O

Asthma

• Strategies: Reduce RR, maintain Vt, maximize expiration time (I:E 1:5), permissive hypercapnia

COPD

• Strategies: Normal TV (6-8 ml/kg), normal PEEP (5-10 cmH2O), longer I:E ratios

Practice Resources

• Practice on the Hamilton T1
• Use Hamilton-Medicals online modules
• Consult expert anesthetists at your base

Acknowledgments: Dr Satya Varnasi and Dr David Ransley for contributions.