falls after TKA

1. Journal Club
Dr John Slattery

2. Article
 Potentially preventable
 Significant morbidity & mortality
  risk due to limited perioperative mobility
 Peripheral nerve block speculated to  risk
 Hypothesis – Older & sicker patients at  risk of
falls & choice of anaesthesia/nerve blocks will
affect this risk

3. Methods
 Database (Premier Perspective Inc):
 January 2006 – September 2010
 400 acute care US hospitals
 Demographics, hospital characteristics, billing
info, ICD-9, procedural codes
 Standardised validation process – 7 step
analysis & 100 crosschecks
 Missing data in 28% of cases
 Inclusion – TKA & anaesthesia info (from
billing)
 Routine admissions & elective procedures

4. Methods
 Primary outcome – Inpatient falls
 Not standardised (ICD-9 “accidents
occurring in a residential institution”)
 ?Follow-up period
 Limited variables e.g. comorbidities
 191,570 records:
 10.9% - neuraxial block
 12.9% - combined neuraxial & GA
 76.2% - GA

5. Results
 1.6% fall rate (previously reported 0.85%)
 Older – 68.9 years vs 66.3 years
 GA – 1.6% (NA 1.3%, combined 1.5%)
  comorbidities
 12.1% received peripheral nerve block
 No difference in age/sex/comorbidity
burden
 No significant difference between
proportion falling with peripheral block &
without

6. Multiple logistical regression

7. Comorbidities

8. Complications

9. Conclusion
 1.6% fell
  reporting/aging population
 Inpatient falls associated with worse
outcomes
 Population suffering from falls were older,
male & with more comorbidities
 Reduced motor strength
 Impaired reflexes/balance
 Less willing to ask for help
 More risky/overestimate abilities

10. Conclusion
 Falls associated with various
comorbidities
 Altered sensorium/perceptions
(OSA/psycosis)
 Neuraxial anaesthesia lower odds of falls
compared with GA alone (30% risk )
 Less influence on postoperative cognitive
function & delirium
 Peripheral nerve blocks had no significant
impact on the risk of falls


11. Limitations
 Retrospective case-control study
 Selection bias
 Database with missing information despite
validity checks
 Restricted to elective procedures
 Definition of inpatient falls non-standardised
(PPV of inpatient falls from ICD-9 coding =
54%)
 Limited variables e.g comorbidities –
Neurological disease
 No distinction made between impact of
different types of peripheral nerve block,
doses used etc.

12. Limitations
 ?Alternate practice
 10.9% neuraxial anaesthesia
 No difference in comorbidity burden between
peripheral blockade & non-blockade
 No causal relationships can be made from the
data
 Any falls prevention techniques used in each
hospital
 Insufficient power to comment on the role of
peripheral nerve block

13. References
 Memtsoudis S, Danninger T, Rasul R, et
al. Inpatient Falls after Total Knee
Arthroscopy. The Role of Anesthesia Type
and Peripheral Nerve Blocks.
Anesthesiology, 2014; 120: 551-563.

14. Questions?