1. Grupo Neuroanestesia HUFSFB
REPORTS OF ORIGINAL INVESTIGATIONS
Effects of an alveolar recruitment maneuver on subdural
pressure, brain swelling, and mean arterial pressure in patients
undergoing supratentorial tumour resection: a randomized
crossover study
Effets d’une manœuvre de recrutement alve´olaire sur la pression
sous-durale, l’œde`me ce´re´bral et la tension arte´rielle moyenne
chez les patients subissant une re´section de tumeur sus-tentorielle:
une e´tude croise´e randomise´e
Alana M. Flexman, MD, FRCPC . Peter A. Gooderham, MD, FRCSC .
Donald E. Griesdale, MD, MSc, FRCPC . Ruth Argue, BScN . Brian Toyota, MD,
FRCSC
Received: 22 August 2016 / Revised: 11 January 2017 / Accepted: 13 March 2017
Ó Canadian Anesthesiologists’ Society 2017
REPORTS OF ORIGINAL INVESTIGATIONS
Effects of an alveolar recruitment maneuver on subdural
pressure, brain swelling, and mean arterial pressure in patients
undergoing supratentorial tumour resection: a randomized
crossover study
Effets d’une manœuvre de recrutement alve´olaire sur la pression
sous-durale, l’œde`me ce´re´bral et la tension arte´rielle moyenne
chez les patients subissant une re´section de tumeur sus-tentorielle:
une e´tude croise´e randomise´e
Alana M. Flexman, MD, FRCPC . Peter A. Gooderham, MD, FRCSC .
Donald E. Griesdale, MD, MSc, FRCPC . Ruth Argue, BScN . Brian Toyota, MD,
FRCSC
Received: 22 August 2016 / Revised: 11 January 2017 / Accepted: 13 March 2017
Ó Canadian Anesthesiologists’ Society 2017
Abstract
Purpose Although recruitment maneuvers have been
advocated as part of a lung protective ventilation
strategy, their effects on cerebral physiology during
elective neurosurgery are unknown. Our objectives were
to determine the effects of an alveolar recruitment
maneuver on subdural pressure (SDP), brain relaxation
Methods In this prospective crossover study, patients
scheduled for resection of a supratentorial brain tumour
were randomized to undergo either a recruitment
maneuver (30 cm of water for 30 sec) or a ‘‘sham’’
maneuver (5 cm of water for 30 sec), followed by the
alternative intervention after a 90-sec equilibration period.
Subdural pressure was measured through a dural
DOI 10.1007/s12630-017-0863-7
2. INTRODUCCIÓN
• MRA à Oxigenación, reclutamiento alveolar, disminución stress alveolar
• Ventilación protectora
• MRA + BVC + PEEP à < Mortalidad à SDRA
• Potencial beneficio à Neuroquirurgicos
• Efecto Altas presiones intratoracias à PIC, PPC
• TCE à Afectación à Electiva??
3. OBJETIVO
• “Our objectives were to determine the effects of an alveolar
recruitment maneuver on subdural pressure (SDP), brain
relaxation score (BRS), and cerebral perfusion pressure
among patients undergoing supratentorial tumour resection”
4. METODOLOGÍA
• Vancouver General Hospital
• Clinical Research Ethics Board of the University of British Columbia
• ClinicalTrials.gov (NCT02093117)
• 30 cm of water continuous airway pressure for 30 sec
• ‘‘sham’’ recruitment maneuver: 5 cm of water for 30 sec
• brief 90-sec equilibration period à 30-sec baseline measurement
5. METODOLOGÍA
0 1
Recruitment
Maneuver
Sham
Time (min)
Baseline Treatment Period #2Equilibration
30 seconds 30 seconds 90 seconds 30 seconds
3.5
Treatment Period #1
Randomization
R
Sham
Recruitment
Maneuver
SD0 SD2SD1
2.5 3.0
Baseline
30 seconds
SD0
0.5
Fig. 1 The randomized crossover study design involved two
treatment periods of either a recruitment maneuver of 30 cm H2O
for 30 sec, or a sham procedures of 5 cm H2O for 30 sec, separated by
an equilibration period of 120 sec. Subdural pressure (SD) was
measured prior to and at the end of each treatment period
Recruitment maneuver during brain tumor resection
7. • ASA + LAI
• Inducción a discreción
• Remifentanil 0.05-0.3 mcg/kg/min +
sevoflurane o desflurane 0.5-0.7
MAC
• Rocuronio
• VC 6-8 ml/kg à PaCO2 32-38
mmHg
• Dexametasona, manitol
• Supino + lateral
• J: 22G/0.9-mm à Subdural (PIC)
à c/5 seg
• Relajación cerebral à Neurocirujano
(1-4)
• PPC (PAM-PIC) à c/ 5 seg
METODOLOGÍA
8. • MSD à 7.0 (5.5) mmHg.
• Type I error of 0.05, a type II error of 0.2, and a two-sided
• Approximately 22 patients à ≠ 3.5 mmHg
• Shapiro-Wilk W-test
• Student’s t test and Wilcoxon signed-rank test
• Spearman’s rank correlation coefficient.
METODOLOGÍA
9. • 22 pacientes à 21
• Fentanyl, lidocaine, propofol, and rocuronium à 100%
• TIVA à 1 (NVPO)
• 14 (67%) à Manitol
RESULTADOS
10. RESULTADOS
Table 1 Characteristics of the study population
Variable Overall (n=21) Recruitment Maneuver Sham Maneuver
Age, mean (SD) 52 (17)
Body mass index, mean (SD) 27 (11)
Tumour diameter (mm) mean (SD) 35 (22)
Midline shift present, n (%) 6 (29)
Recurrent tumour, n (%) 5 (24)
Right-sided tumour, n (%) 10 (50)
Tumour type, n (%)
Glioblastoma 2 (9.5)
Glioma 9 (42.9)
Meningioma 6 (28.6)
Metastasis 4 (19)
Recruitment maneuver first, n (%) 11 (52)
Baseline Measurements
Baseline PaCO2 (mmHg), mean (SD) 36 (3) 35 (3)
Baseline SDP (mmHg), mean (SD) 12 (4) 12 (4)
Baseline BRS, median [IQR] 2 [1-2] 2 [1-2]
Baseline MAP (mmHg), mean (SD) 67 (8) 67 (9)
Baseline HR (beatsÁmin-1
), mean (SD) 58 (7) 58 (7)
BRS = brain relaxation score; HR = heart rate; IQR = interquartile range; MAP = mean arterial pressure; PaCO2 = arterial partial pressure of
carbon dioxide; SD = standard deviation;SDP = subdural pressure
Table 2 Effects of the recruitment and sham maneuvers on outcome variables
Recruitment maneuver during brain tumor resection
11. RESULTADOS
volatile anesthesia (desflurane or sevoflurane). Fourteen
participants (67%) received mannitol prior to the study
intervention, and all participants received dexamethasone.
Baseline subdural pressure, BRS, MAP, HR, and PaCO2
were similar between the two treatment groups (Table 1).
The recruitment maneuvers were not abandoned in any
Mean arterial pressure decreased significantly more in the
recruitment maneuver compared with the sham maneuver
(mean difference, -9.0 mmHg; 95% CI, -12.5 to -5.6; P
0.0001). As a result of the increased subdural pressure
and decreased MAP, the calculated cerebral perfusion
pressure (MAP-SDP) decreased an average of 14 mmHg
Baseline PaCO2 (mmHg), mean (SD) 36 (3) 35 (3)
Baseline SDP (mmHg), mean (SD) 12 (4) 12 (4)
Baseline BRS, median [IQR] 2 [1-2] 2 [1-2]
Baseline MAP (mmHg), mean (SD) 67 (8) 67 (9)
Baseline HR (beatsÁmin-1
), mean (SD) 58 (7) 58 (7)
BRS = brain relaxation score; HR = heart rate; IQR = interquartile range; MAP = mean arterial pressure; PaCO2 = arterial partial pressure of
carbon dioxide; SD = standard deviation;SDP = subdural pressure
Table 2 Effects of the recruitment and sham maneuvers on outcome variables
Variable Recruitment Sham Difference (95% CI) P value
SDP change, mean (SD) 4.7 (3.6) 0.8 (1.8) 3.9 (2.2 to 5.6) 0.001
BRS change, median [IQR] 0 [0-0] 0 [0-0] 0 (-1 to 1) 1.00
MAP change, mean (SD) -9.2 (7.2) -0.2 (1.5) -9.0 (-12.5 to -5.6) 0.001
HR change, mean (SD) -5.5 (5.1) 0.8 (1.1) -6.3 (-8.7 to -3.9) 0.001
BRS = brain relaxation score; CI = confidence interval; HR = heart rate; IQR = interquartile range; MAP = mean arterial pressure; SD = standard
deviation; SDP = subdural pressure. SDP and MAP reported in mmHg; HR reported in beats per minute
MRA à PPC = -14 mmHg (95% CI, 4 to 24)
13. • ∆ SDP ≈
• Edad, (rho, -0.28; P = 0.28)
• BMI (rho, 0.14; P = 0.53)
• Diámetro del tumor (rho, 0.06; P = 0.80)
• Desviación de línea media (P = 0.18).
• > SDP: 1º MRA = 1º Placebo DM: -1.2 mmHg, (-4.5 to 2.2; P = 0.47).
RESULTADOS
14. DISCUSIÓN
• > SDP, < PAM y PIC à << PPC 14 mmHg (95% CI, 4 to 24), BRS =
• El comportamiento en estos pacientes ambulatorios à TCE
• HSAà > PIC 7 mmHg, < PAM 13 mmHg à MRA: 35 cmH2O for 40 seg.
• Neuro-UCI à > PIC 3 mmHg, < PAM 11 mmHg à MRA: 60 cmH2O.
• Impacto clinico à Largo plazo
• Riesgo / Beneficio
• Cx de Resección tumor cerebral à Incidencia global 4.4% à Falla respiratoria
aguda.
15. Limitaciones
• SDP ≈ PIC
• Validez externa (tumores infratentoriales, prono, otras patologías
intracraneales, otras maniobras de reclutamiento).
• Manitol à BRS = (Poder)
• PPC à Resultados
16. CONCLUSIONES
• “In conclusion, our study results show that a recruitment maneuver of 30
cmH2O for 30 sec results in an average increase in subdural pressure of 4.7
mmHg (95% CI, 1 to 12), leading to a mean reduction in cerebral perfusion
pressure of 14 mmHg (95% CI, 4 to 24) (…) Whether this finding correlates
with long-term clinically meaningful outcomes is a potential area of future
research that should be investigated prior to recommending routine use of
these maneuvers”
