Choose the Capno-T if you want the smallest EtCO₂ monitor: 80 g with its lithium battery and adult adapter, 38 × 42 × 44 mm, ready to use without calibration and running 6–8 hours on a full charge. Choose the Capno-H if you want a larger 2.8-inch screen, mains input of 100–250 V and the option of adding SpO₂ and pulse. Both measure CO₂ from 0 to 150 mmHg with the same accuracy bands, update EtCO₂ every breath, count respiration from 3 to 150 per minute, keep a 24-hour trend and give audible and visual alarms.
Capno-H or Capno-T: which portable capnograph should a veterinary clinic buy?
The two models share the CO₂ measurement; they differ in size, screen, power supply and optional parameters. The table lists the published figures that usually decide the choice.
| Decision point | Capno-H | Capno-T |
| Weight (with lithium battery and adult adapter) | 400 g | 80 g |
| Display | 2.8-inch colour TFT | 1.5-inch colour TFT, readable from more than 5 m |
| Parameters | EtCO₂/CO₂ and respiration rate; SpO₂ and pulse optional | EtCO₂/CO₂ and respiration rate |
| CO₂ range and units | 0–150 mmHg; mmHg, kPa or % | 0–150 mmHg; mmHg, kPa or % |
| Respiration rate | 3–150 /min | 3–150 /min |
| Battery | Rechargeable lithium, 3.6 V / 3800 mAh | Rechargeable lithium, 3.7 V / 1.35 Ah; 6–8 h after a full charge |
| Mains input | AC 100–250 V, 50/60 Hz; ≤5 VA | AC 220 V, 50 Hz; ≤10 VA |
| Operating environment | 5–40 °C; 30–75% RH non-condensing; 55–115 kPa | 5–40 °C; 30–75% RH non-condensing; 86–106 kPa |
| Trend and alarms | 24-hour trend kept after power-off; audible and visual alarms | 24-hour trend; audible and visual alarms |
The Capno-T suits an anaesthesia station, recovery or transport where the monitor should add almost no weight and take no bench space. The Capno-H suits clinics that want one handheld unit for CO₂ plus SpO₂ and pulse, that run on 110–120 V mains, or that work at high altitude: its operating pressure range goes down to 55 kPa, against 86 kPa for the Capno-T.
How accurate are the Capno-H and Capno-T EtCO₂ readings?
Both models publish the same EtCO₂ accuracy, which tightens at the lower end of the range:
| EtCO₂ reading | Published accuracy (Capno-H and Capno-T) |
| 0–40 mmHg | ±2 mmHg |
| 41–70 mmHg | ±5% |
| 71–100 mmHg | ±8% |
| 100–150 mmHg | ±10% |
The Capno-H uses infrared CO₂ analysis with temperature and pressure compensation and zero readjustment. The Capno-T compensates for atmospheric pressure automatically, shows the first EtCO₂ value in 5 seconds and accurate readings in 15 seconds; its respiration-rate accuracy is the greater of ±1% or ±1 breath per minute. Both let you switch the display between mmHg, kPa and %, so the unit can match the one used in your anaesthesia records.
Can either capnograph also measure SpO₂ and pulse?
Only the Capno-H, and only as an option. With the SpO₂ option it measures SpO₂ from 0 to 100% (±3% at 50–69%, ±2% at 70–100%) and pulse from 30 to 250 bpm (the greater of ±2 bpm or ±2%). If you need it, ask for the SpO₂ sensor and extension cable to be listed as separate lines in the quotation.
The Capno-T measures CO₂ and respiration rate. If you prefer its size but also want oxygen saturation, pair it with the H-100V handheld pulse oximeter (SpO₂ 1–100%, pulse 25–350 bpm) or the 250 g HM-3T mini monitor with SpO₂, NIBP and temperature.
How long does the battery last, and what mains voltage do they need?
The Capno-T runs 6–8 hours on its 3.7 V / 1.35 Ah lithium battery after a full charge. Its published mains input is AC 220 V, 50 Hz, so in 110–120 V countries confirm the charger version and plug type before ordering. The Capno-H takes AC 100–250 V at 50 or 60 Hz and uses a 3.6 V / 3800 mAh lithium battery, which makes it the simpler choice when the same model will be shipped to clinics on different mains supplies.
Which airway adapters and spare parts should be in the quotation?
Both published weights include an adult adapter, and both models alarm when the adapter needs checking. For cats, small dogs and other small patients, the adapter size matters as much as the monitor. A complete quotation lists:
- The number and sizes of airway adapters supplied, based on the smallest patients you anaesthetise.
- The charger version and plug type for your mains supply (especially for the Capno-T).
- A spare lithium battery if the unit will be used for long procedures or transport.
- For the Capno-H with the SpO₂ option: the SpO₂ sensor type and extension cable.
- Replacement adapters and other consumables, with part numbers, so reorders match the original kit.
Stand-alone capnograph or a patient monitor with EtCO₂?
A stand-alone capnograph adds CO₂ monitoring to an existing anaesthesia machine and monitor without replacing them, and it can move between the surgery, recovery and the ambulance. If you are equipping a new operating room, compare it with a veterinary patient monitor that has a CO₂ module, so ECG, SpO₂, NIBP, temperature and EtCO₂ appear on one screen.
What to send HQS for a Capno-H or Capno-T quote
- Model and quantity, and whether you need the Capno-H SpO₂ option.
- Your mains voltage, frequency and plug type.
- The species and smallest body sizes you monitor, so the adapter sizes can be matched.
- The accessories and spare parts you want quoted.
- The destination country, so the shipping and import documents for that market are prepared with the quotation.
