Anaesthesia in the Beach Chair Posihon

38 Pages·2013·6.8 MB·English

by  Mark Hayman

Anaesthesia
 in
 the

Beach
 Chair
 Posi0on

NEURO
 SIG
 Mee0ng

Queenstown
 7-­‐2013

Mark
 Hayman

MBBS,
 MPH,
 FANZCA
Outline

1.  Incidence
 of
 strokes
 during
 beach
 chair

posi0oning
 (BCP)

2.  Physiology
 of
 CBF
 in
 upright
 posi0on

3.  Monitoring
 for
 inadequate
 CBF

4.  Management
 sugges0ons

5.  Conclusions
Disclosures

•  None!
Case
 Report:
 NSW
 2011

•  50yo
 former
 rugby
 player
 died
 of
 a
 massive
 stroke

during
 arthroscopic
 shoulder
 surgery
 in
 “beach-­‐chair”

posi0on.

•  “..caused
 by
 a
 failure
 to
 es0mate
 and
 maintain
 an

appropriate
 level
 of
 mean
 arterial
 pressure
 in
 the

blood
 supply
 of
 the
 brain”

(NSW
 coroner)

•  recommenda/on
 that
 all
 anaesthe0c
 departments

“develop
 guidelines
 for
 the
 appropriate
 adjustment

for
 the
 hydrosta0c
 gradient
 by
 anaesthe0sts
 when

calcula0ng
 MAP
 for
 ‘beach-­‐chair’
 surgery”.
Other
 case
 reports

•  4
 cases
 reported
 by
 Pohl
 &
 Cullen
 in
 2005,

ages
 47-­‐57

•  3
 recent
 cases
 from
 France
 with
 GA
 &

interscalene
 block,
 ages
 54-­‐58

•  Common
 features:
 young
 pa0ents,
 minor

comorbi0es
 &
 periods
 of
 intra-­‐op

hypotension.

•  Morbidity
 presumed
 to
 be
 result
 of
 ischaemic

stroke
 due
 to
 cerebral
 hypoperfusion.

Pohl
 &
 Cullen,
 J
 Clin
 Anesth,
 2005

Villevieille,
 Ann
 Fr
 Anesth,
 2012
Case:
 Incomplete
 Circle
 of
 Willis

•  50yo
 male,
 180cm
 tall,
 smoker,
 Pre-­‐op
 BP
 110/75

•  SBP
 @
 arm
 =
 95-­‐100mmHg,
 lowest
 MAP=61mmHg
 (≈35-­‐40mmHg
 @
 Head)

?
 ACom

 ?
 PCom

MRI
 @
 2
 months:
 Lei
 Anterior
 &
 Middle

Cerebral
 Artery
 territory
 infarct

CTA:
 incomplete
 circle
 of
 willis.

Drummond,
 A&A,
 2012
Incidence
 of
 Brain
 Injury
 following
 surgery
 in

Beach
 Chair
 Posi0on?

N=5177
  BP
  Av.
 Mean
  Average
 BP
  %
 Pa1ents
  Average

  Measureme BP
  Drop
 %
  >1
 episode
  Hypotensio
Retrospec1ve
  nt
  BP
 Drop
  n
 Time
 per

Series

  >40%
 from
  episode

baseline

A
 Line
  75
  14.4
  51%

(heart)

Shoulder

n=682

16.6min

Surgery

NIBP
  74
  19.3
  48%

n=3545

A
 line
 (heart)
  78
  17.6

n=422

Neuro

52%
  16.7min

Cases

A
 Line
 (head)
  75
  19.7

n=528

No
 immediate
 postopera0ve
 catastrophic
 outcomes
 occurred,

upper
 95%
 CI
 =
 7
 per
 10000

Pin-­‐On
 &
 Munis,
 A&A
 2013
Incidence
 of
 Intraopera0ve
 Stroke

•  Survey
 of
 orthopaedic
 surgeons,
 cases
 >
 200K

•  Es0mated
 stroke
 rate:
 0.004%

•  All
 events
 occurred
 in
 pa0ents
 in
 the
 BCP

Friedman,
 Orthopaedics,
 2009

•  And
 yet
 hypotension
 is
 common
 in
 the
 BCP

posi0on.

Pin-­‐On,
 2013,
 Friedman
 2009,
 Yadeau
 2011,
 Rohrbaugh
 2013

•  So
 is
 hypotension
 the
 cause?

 Perhaps…

Lam
 &
 Baldwin,
 Blood
 Pressure
 &
 Adverse
 Periopera/ve
 Neurologic

Outcomes:
 An
 Uncomfortable
 Posi/on,
 A&A
 2012
What
 is
 Hypotension?

•  BP
 while
 asleep:
 drop
 ≈
 30%
 from
 baseline

SBP

MAP

Soo
 et
 al,
 Anaesthesia,
 2011
Blood
 Pressure
 –
 what
 is
 baseline?

Pre-­‐op
 baseline

Day0me
 median
 -­‐9.5%

MAP

mmHg
  Sleep
 median

 -­‐19.5%

Sleep
 nadir

 -­‐33.4%

Intra-­‐op
 nadir

 -­‐35.2%

Soo
 et
 al,
 Anaesthesia,
 2011