Journal club tracheostomy

1. Peter McCanny

3. Rationale:
- ‘little evidence to guide clinicians regarding optimal timing for
tracheostomy in ICUs’.
Objective:
- To test whether ‘early’ vs ‘late’ tracheostomy would result in
lower mortality in adult patients receiving mechanical
ventilation (MV).
Design:
- Open multicentre RCT, 2004- 2011
- 72 ICU’s in UK (70 general/ 2 cardiothoracic;
13 university/ 59 non-uni)

4. Participants:
- 909 patients: MV <4 days
- Identified by treating physician as likely to require >7days MV
Interventions:
- Randomised to receive ‘early’ (within 4 days) or ‘late’ (after 10
days, if still indicated) tracheostomy.
Outcome measures:
- Primary outcome= 30 day mortality
- Intention to treat analysis

6. ‘For adult patients on MV in UK ICU’s, trachy within 4 days
of critical care admission was not associated with
improvement in 30d mortality, or other important secondary
outcomes’
‘Early tracheostomy should be avoided unless tools to
accurately predict the duration of mechanical ventilation on
individual patients can be developed and validated’

7. • Sponsorship/ conflicting interests of authors?
- Funded by UK Intensive Care Society and Medical
Research Council (UK).
- No industry involvement.
• Journal?
• Authors?

8. • RECRUITMENT:
- Were study subjects representative of the target
population?
- POSSIBLY

9. (12%)

10. • RECRUITMENT
- Was sample adequately powered?
- Pilot studies performed.
- Adjusted during study following updated data in
systematic review (2006).
- Final planned sample size of 1692 patients to detect a
6.3% absolute (21% relative ) reduction in mortality.
- INTENDED SAMPLE SIZE NOT REACHED:
‘final 899- patient study had the power to detect an 8.3%
absolute change in 30-day mortality from the late group
value of 31.5% with 80% power and 5% level of
significance.’

11. • ALLOCATION:
- Was the randomisation method unbiased?
- YES
- Automated 24hr phone service, using algorithm to
minimise imbalance between groups (centre, age, sex,
diagnostic groups).
- Were the groups matched as closely as possible at start
of trial?

13. • MAINTENANCE:
- Was comparable treatment of the 2 groups maintained
throughout the study?
- NO:
- ‘EARLY ‘ group: 85% of patients had trachy within 4 days.
- ‘EARLY’ group: 6.8% did not receive trachy at all.
- ‘LATE’ group: 54% did not receive trachy at all!
- Was transparent information provided to show how and
where subjects were ‘lost’ during the trial?
• - YES: detailed in methods and results sections.

15. • MAINTENANCE:
- Was transparent information provided to show how and
where subjects were ‘lost’ during the trial?
- YES
- Detailed in methods and results sections.

16. •BLINDING:
- Were outcomes measured with blinded subjects and
assessors?
- NO
- Caring team and analysis team not blinded, by nature
of study design.
- Subjects/ relatives not blinded (consent had to be
provided).

17. • OBJECTIVITY OF OUTCOME MEASUREMENT:
- Were outcomes measured objectively?
PRIMARY OUTCOME:
- 30- day mortality…..YES
SECONDARY OUTCOMES:
- ICU, hospital discharge mortality….YES
- 2yr mortality….YES (note: added post- hoc)
- Duration of mechanical ventilation….YES
- Use of sedatives….YES

18. • Could the effect have been due to chance?
• What measure was used and how large was the treatment
effect?

20. • Are the conclusions valid?
- Debatable, given issues around change in sample size,
powering.
• External validity and Generalisability of results to our
population?
- UK system different from ours (occupancy, bed
pressures etc)
- High proportion of ‘Non- University hospitals’
- High overall mortality rates (sick patients)
- Similar patient cohort (except neurosurg), mostly perc
trachy, performed by senior physicians.

21. • Ability of physicians to predict which patients will require MV
> 7 days may be unreliable.
• Despite flaws in study (especially underpowering)- it included
large patient numbers, with a transparent analysis, and
provides us with useful data.
• Early tracheostomy is probably unnecessary in most patients
who require mechanical ventilation for respiratory failure.
• This is in keeping with findings of other randomised studies
on timing of trachy insertion.

24. Background:
- Percutaneous dilational tracheostomy (PDT) frequently
performed by Intensivists in adult ICU’s.
- Complications rare but serious (including perforation,
death)
- Realtime Ultrasound (US) guidance has been proposed to
decrease complications and improve accuracy of
tracheal puncture.

25. Methods:
- 50 patients receiving PDT were randomly assigned to have
tracheal puncture carried out using either traditional anatomical
landmarks or real-time US guidance.
- Puncture position recorded using bronchoscopy.
- Blinded assessors determined the deviation of puncture off
midline, and whether appropriate longitudinal position
(between 1st
- 4th
tracheal rings) was achieved.

27. Results:
Anatomical Ultrasound Stats
Mean deviation from
midline (degrees)
35 (+/- 5) 15 (+/- 3) p= 0.001
Proportion of
‘appropriate’ punctures
(0-30 degrees)
50% 87% RR= 1.74
(CI’s 1.13- 2.67)
p= 0.006
1st
pass success rate 58% 87% RR= 1.49
(CI’s 1.03- 2.07)
p= 0.028
Complication rate 37% 22% RR= 0.58
(CI’s 0.23- 2.47)
p= 0.24

28. Conclusions:
- US guidance significantly improved the rate of 1st
pass puncture
and puncture accuracy.
- Fewer complications were observed, but this did not reach
statistical significance.
- Results suggest wider general use of real-time US guidance as
an additional tool to improve PDT.

29. • Sponsorship/ conflict of interests?
- Unrestricted research grant provided by Australian
Society for Ultrasound in Medicine (ASUM)
- ‘ASUM had no involvement, direct or indirect, in the
design, conduct, or reporting of this trial.’
• Journal? Authors?

30. • RECRUITMENT:
- Were study subjects representative of the target
population?
- PROBABLY
- Though 17 out of potential 72 patients were missed.

31. • RECRUITMENT
- Was sample adequately powered?
- No pilot study for power calculation.
- Sample size calculated based on PRESUMED average
degrees of displacement from midline (25 +/- 15 degrees
from midline in landmark group; and 15+/- 10 degrees in US
group)
- Used assumptions to estimate sample size of 50 required
to detect 80% power with 0.05 CI.

32. • ALLOCATION:
- Was the randomisation method unbiased?
- YES
- According to previously published guidelines
- Were the groups matched as closely as possible at start
of trial?

34. • MAINTENANCE:
- Was comparable treatment of the 2 groups maintained
throughout the study?
- Was transparent information provided to show how and
where subjects were ‘lost’ during the trial?
- Was transparent information provided to show how and
where subjects were ‘lost’ during the trial?

36. •BLINDING:
- Were outcomes measured with blinded subjects and
assessors?
- CARING team: not blinded
- ANALYSIS team: blinded
- Subjects/ relatives not blinded (consent had to be
provided).

37. • OBJECTIVITY OF OUTCOME MEASUREMENT:
- Were outcomes measured objectively?
PRIMARY OUTCOMES:
- Accuracy of tracheal puncture (<30 degrees from
midline)…..
- Appropriate longitudinal puncture (between 1st
- 4th
tracheal rings)….
- Some subjectivity involved, but attempts to minimise
this (consensus opinion of 2 assessors used).
SECONDARY OUTCOMES:
- 1st
pass tracheal puncture….YES
- Measures of safety….some objective, some subjective.

38. • Could the effect have been due to chance?
• What measure was used and how large was the treatment
effect?

39. • Bear in mind small numbers and powering methods of study

40. • Are the conclusions valid?
- YES, but depends on how you interpret in light of power
calculation and small numbers.
• External validity and Generalisability of results to our
population?
- YES:
- Based in Sydney hospitals, with similar patient
cohort.
- PDT practices similar to local ICU’s.

41. • Use of real- time US can improve accuracy of tracheal
puncture in PDT.
• Current study does not allow us to connect this with a clear
improvement in complication rate / outcome (although
intuitive to expect this).
• Hard not to use Ultrasound, given availability and
familiarity with its use nowadays.