Association between temporal mean arterial pressure and brachial noninvasive blood pressure during shoulder surgery in the beach chair position during general anesthesia

doi:10.1016/j.jse.2014.05.011

Journal of Shoulder and Elbow Surgery

Volume 24, Issue 1, January 2015, Pages 127-132

https://doi.org/10.1016/j.jse.2014.05.011 Get rights and content

Background

Estimation of cerebral perfusion pressure during elective shoulder surgery in the beach chair position is regularly performed by noninvasive brachial blood pressure (NIBP) measurements. The relationship between brachial mean arterial pressure and estimated temporal mean arterial pressure (eTMAP) is not well established and may vary with patient positioning. Establishing a ratio between eTMAP and NIBP at varying positions may provide a more accurate estimation of cerebral perfusion using noninvasive measurements.

Methods

This prospective study included 57 patients undergoing elective shoulder surgery in the beach chair position. All patients received an interscalene block and general anesthesia. After the induction of general anesthesia, values for eTMAP and NIBP were recorded at 0°, 30°, and 70° of incline.

Results

A statistically significant, strong, and direct correlation between NIBP and eTMAP was found at 0° (r = 0.909, P ≤ .001), 30° (r = 0.874, P < .001), and 70° (r = 0.819, P < .001) of incline. The mean ratios of eTMAP to NIBP at 0°, 30°, and 70° of incline were 0.939 (95% confidence interval [CI], 0.915-0.964), 0.738 (95% CI, 0.704-0.771), and 0.629 (95% CI, 0.584-0.673), respectively. There was a statistically significant decrease in the eTMAP/NIBP ratio as patient incline increased from 0° to 30° (P < .001) and from 30° to 70° (P < .001).

Conclusion

The eTMAP-to-NIBP ratio decreases as an anesthetized patient is placed into the beach chair position. Awareness of this phenomenon is important to ensure adequate cerebral perfusion and prevent hypoxic-related injuries.

Section snippets

Materials and methods

This was a prospective cohort study of 57 patients (32 men, 25 women) undergoing elective shoulder surgery (56 shoulder arthroplasty and 1 humeral fracture fixation), from July 2012 to July 2013, using noninvasive arterial monitoring of blood pressure in the beach chair position. Patients were included if they were having an elective open shoulder procedure and were at least 18 years old. Excluded were minors, pregnant patients, prisoners, and patients with impaired decision-making abilities.

Results

Our results demonstrate a statistically significant effect of inclination on NIBP (P < .001) and eTMAP (P < .001). Mean NIPB was highest at 0° of incline (110 ± 24 mm Hg), with statistically significant decreases seen at inclines of 30° (94 ± 20 mm Hg) and at 70° (81 ± 19 mm Hg; P < .001 for all pairwise comparisons). Increasing the degree of inclination also elicited significant reductions in eTMAP. The highest mean values of eTMAP were recorded at 0° of incline (104 ± 24 mm Hg), with

Discussion

As hypothesized, a statistically significant, strong, and direct correlation exists between NIBP and eTMAP at 0°, 30°, and 70°of inclination. However, contrary to our hypothesis, we found that as the inclination angle increased, a significant decline occurred in the eTMAP-to-NIBP ratio. These results permit a calculated adjustment in NIBP to better reflect expected eTMAP at 0°, 30°, and 70°of inclination. With these ratios accounted for, a change in NIBP at varying positions will provide a more

Conclusion

The ratio of eTMAP to NIBP decreases as an anesthetized patient is placed into the beach chair position. Estimated MAP at the level of the brain can be calculated from NIBP measurements by using defined ratios. These ratios are important in ensuring adequate cerebral perfusion and preventing hypoxic-related injury reported with this position. Proper adjustment in pressure control should be made based on patient position.

Disclaimer

The authors, their immediate families, and any research foundations with which they are affiliated have not received any financial payments or other benefits from any commercial entity related to the subject of this article.

References (42)

N. Alperin et al.
MRI study of cerebral blood flow and CSF flow dynamics in an upright posture: the effect of posture on the intracranial compliance and pressure
Acta Neurochir Suppl
(2005)
A.A. Bendo et al.
Anesthesia for neurosurgery
M.T. Bhatti et al.
Visual loss and ophthalmoplegia after shoulder surgery
Anesth Analg
(2003)
D.J. Cullen et al.
Beach chair position may decrease cerebral perfusion; catastrophic outcomes have occurred
APSF Newsletter
(2007)
D.G. Dalrymple et al.
Cardiorespiratory effects of the sitting position in neurosurgery
Br J Anaesth
(1979)
J.C. Drummond
The lower limit of autoregulation: time to revise our thinking?
Anesthesiology
(1997)
M.A. Frey et al.
Cardiovascular responses to postural changes: differences with age for women and men
J Clin Pharmacol
(1994)
D.J. Friedman et al.
Prevalence of cerebrovascular events during shoulder surgery and association with patient position
Orthopedics
(2009)
R. Gillespie et al.
The safety of controlled hypotension for shoulder arthroscopy in the beach-chair position
J Bone Joint Surg Am
(2012)
R. Kirby et al.
Lower limit of cerebral autoregulation questioned
APSF Newsletter
(2009)

T. Koga et al.

Pituitary apoplexy during general anesthesia in beach chair position for shoulder joint arthroplasty

J Anesth

(2010)

J.L. Koh et al.

Neer Award 2012: cerebral oxygenation in the beach chair position: a prospective study on the effect of general anesthesia compared with regional anesthesia and sedation

J Shoulder Elbow Surg

(2013)

M.J. Krabbe-Hartkamp et al.

Circle of Willis: morphologic variation on three-dimensional time-of-flight MR angiograms

Radiology

(1998)

P. Kurtz et al.

Continuous EEG monitoring: is it ready for prime time?

Curr Opin Crit Care

(2009)

F.S. Larsen et al.

Transcranial Doppler is valid for determination of the lower limit of cerebral blood flow autoregulation

Stroke

(1994)

B.F. Matta et al.

Direct cerebral vasodilatory effects of sevoflurane and isoflurane

Anesthesiology

(1999)

D. Mazzon et al.

Beach chair position, general anesthesia and deliberated hypotension during shoulder surgery: a dangerous combination!

Minerva Anestesiol

(2009)

A.T. Moerman et al.

Cerebral oxygen desaturation during beach chair position

Eur J Anaesthesiol

(2012)

G.S. Murphy et al.

Cerebral oxygen desaturation events assessed by near-infrared spectroscopy during shoulder arthroscopy in the beach chair and lateral decubitus positions

Anesth Analg

(2010)

Y. Ogawa et al.

The effect of sevoflurane on dynamic cerebral blood flow autoregulation assessed by spectral and transfer function analysis

Anesth Analg

(2006)

H. Ohsumi et al.

Preoperative estimation of cerebral blood flow autoregulation curve for control of cerebral circulation after cerebral revascularization

Resuscitation

(1985)

Cited by (5)

Fluid preloading before beach chair positioning for arthroscopic shoulder procedures: a randomized controlled trial
2022, Brazilian Journal of Anesthesiology (English Edition)
Citation Excerpt :
Therefore, patients who were known to use ACEIs and ARBs for preventing deep hypotension were excluded from the study. Triplet et al. stated that NIBP measurement is not reliable in the BCP, especially when used to predict cerebral perfusion pressure.17 In their study, Papadonikolakis et al. emphasized that blood pressure can be inaccurately measured up to 50...mmHg depending on the location of the blood pressure cuff.2 For this reason, the perspective that patients should be monitored more closely in terms of hemodynamics has become widespread over time.
The Beach Chair Position (BCP) has many advantages such as less neurovascular injury and better intra-articular visualization, but it has also negative consequences, including hemodynamic instability. Although maintaining normal Mean Arterial Pressure (MAP) is important, fluid management is also a crucial concept for hemodynamic stability. The main objective of this study is whether preloading before positioning would be effective for less hemodynamic instability.
This randomized, controlled study was conducted in a single center in the Istanbul University, Istanbul Faculty of Medicine. Forty-nine patients undergoing elective arthroscopic surgery in the BCP were recruited. In the study group, crystalloid fluid at 10...mL.kg^-1 of ideal body weight was administered intravenously 30...min before the BCP for preloading. The primary outcome measures were differences of hemodynamic variables as MAP, Stroke Volume (SV), Heart Rate (HR), and Cardiac Output (CO). The secondary outcome measures were Postoperative Nausea and Vomiting (PONV) rates in postoperative first day, surgical satisfaction scale, total ephedrine dose used during surgery, and total amount of fluid.
The MAP, CO, and SV measurements of the study group were higher than those of the control group in the 5th minute after the BCP (respectively, p...=...0.001, p...=...0.016, p...=...0.01). The total amount of crystalloid and surgical satisfaction scales were higher in the study group (respectively, p...=...0.016, p...=...0.001). Total amount of colloid and ephedrine dose used in the intraoperative period, and PONV rates were lower in the study group (p...=...0.003, p...=...0.018, p...=...0.019, respectively).
Consequently, preloading can be favorable approach to preserve hemodynamic stability.
The beach chair position for shoulder surgery in intravenous general anesthesia and controlled hypotension: Impact on cerebral oxygenation, cerebral blood flow and neurobehavioral outcome
2019, Journal of Clinical Anesthesia
Citation Excerpt :
However, if mean arterial pressure was maintained stable at MAP >70 mm Hg at the acoustic meatus level cerebral autoregulation was not affected [42]. This is in accordance with our findings as using a controlled hypotensive protocol, the decrease of blood pressure was significant in the BCP with a consecutive decrease in cerebral blood flow and cerebral oxygen saturation (Fig. 2) Triplet et al. recently demonstrated that in the BCP the decrease of the eTMAP-to-NIBP ratio was related to the degree of BCP elevation [13]. This is in accordance with the conclusion of a review by Pant et al. investigating the role of BCP in shoulder surgery [16].
The aim of this study was to assess the impact of intravenous general anesthesia and controlled hypotension on cerebral saturation (rScO₂), cerebral blood flow measured as middle cerebral artery blood flow velocity (Vmax MCA) and neurobehavioral outcome in patients scheduled for shoulder surgery in beach chair position.
Prospective, assessor-blinded observational study.
University hospital, shoulder surgery operating room.
Forty ASA I-II patients scheduled for shoulder surgery in beach chair position and controlled hypotension.
Neurological and neurobehavioral tests were performed prior and the day after surgery. The baseline data for near-infrared spectroscopy, bispectral index, cerebral blood flow, PaCO₂ and invasive blood pressure (radial artery) were taken prior anesthesia and after anesthesia induction, after beach chair positioning and all 20 min after surgery start until discharge of the patient.
Neurological and neurobehavioral tests, cerebral saturation (rScO₂) using near-infrared spectroscopy, BIS, cerebral blood flow using Doppler of the middle cerebral artery (Vmax MCA), PaCO₂ and invasive blood pressure assessed at heart and at the external acoustic meatus level.
The incidence of cerebral desaturation events (CDEs) was 25%. The blood pressure drop 5 min after beach chair position measured at the acoustic meatus level in the CDE group was higher compared to patients without CDEs (p = 0.009) as was the rScO₂ (p = 0.039) and the Vmax MCA (p = 0.002). There were no neurological deficits but patients with CDEs showed a greater negative impact on neurobehavioral tests 24 h after surgery compared to patients without CDEs (p = 0.001).
In ASA I-II patients intravenous general anesthesia and controlled hypotension in the beach chair position affects cerebral blood flow and cerebral oxygenation with impact on the neurobehavioral outcome.
Preemptive volume therapy to prevent hemodynamic changes caused by the beach chair position: hydroxyethyl starch 130/0.4 versus Ringer's acetate—a controlled randomized trial
2018, Journal of Shoulder and Elbow Surgery
Citation Excerpt :
From our point of view, there are 2 central issues concerning the perioperative management of patients undergoing BCP. First, conventional measuring of (noninvasive) blood pressure is unreliable in BCP, especially when used to estimate cerebral perfusion pressure.45 Papadonikolakis et al36 emphasized in an editorial that depending on the localization of the cuff, noninvasive blood pressure may vary up to 50 mm Hg between the calf and upper arm (not to mention the brain) in BCP.
Hemodynamic instability frequently occurs in beach chair positioning for surgery, putting patients at risk for cerebral adverse events. This study examined whether preoperative volume loading with crystalloids alone or with a crystalloid-colloid combination can prevent hemodynamic changes that may be causative for unfavorable neurologic outcomes.
The study randomly assigned 43 adult patients undergoing shoulder surgery to 3 study groups. Each group received an infusion of 500 mL of Ringer's acetate between induction of anesthesia and being placed in the beach chair position. The crystalloid group received an additional bolus of 1000 mL Ringer's acetate. The hydroxyethyl starch group was administered an additional bolus of 500 mL of 6% hydroxyethyl starch 130/0.4. Hemodynamic monitoring was accomplished via an esophageal Doppler probe. Cerebral oxygen saturation was examined with near-infrared spectroscopy. Changes in stroke volume variation between the prone and beach chair positions were defined as the primary outcome parameter. Secondary outcomes were changes in cardiac output and cerebral oxygen saturation.
The control group was prematurely stopped after enrollment of 4 patients because of adverse events. In the hydroxyethyl starch group, stroke volume variation remained constant during positioning maneuvers (P = .35), whereas a significant increase was observed in the Ringer's acetate group (P < .01; P = .014 for intergroup comparison). This was also valid for changes in cardiac output. Cerebral oxygen saturation significantly decreased in both groups.
Preprocedural boluses of 500 mL of 6% hydroxyethyl starch 130/0.4 as well as 1000 mL of Ringer's acetate were efficient in preserving hemodynamic conditions during beach chair position.
The effectiveness of cerebral oxygenation monitoring during arthroscopic shoulder surgery in the beach chair position: a randomized blinded study
2018, Journal of Shoulder and Elbow Surgery
Citation Excerpt :
The physiologic responses to general anesthesia that increase this risk for cerebral hypoperfusion in the beach chair position include systemic hypotension with decreased baroreceptor response, gravitational positioning of the head above the heart, and decreased middle cerebral artery blood flow velocity.6,20 Various techniques and instruments have been studied to investigate CDEs with the hope of increasing the ability to detect these events, decreasing their incidence, and improving patient care.3,5,8,12,19,23,24 To our knowledge, this is the first study that investigates the incidence of CDEs during shoulder surgery in the beach chair position using NIRS in a random, blinded fashion.
Beach chair positioning for shoulder surgery is associated with measurable cerebral desaturation events (CDEs) in up to 80% of patients. Near-infrared spectroscopy (NIRS) technology allows real-time measurement of cerebral oxygenation and may minimize the frequency of CDEs. The purpose of this study was to investigate the incidence of CDEs when anesthetists were aware of and blinded to NIRS monitoring and to determine the short-term cognitive effects of surgery in the beach chair position.
NIRS was used to monitor cerebral oxygenation saturation in 41 consecutive patients undergoing arthroscopic shoulder surgery in the beach chair position. Patients were randomized to 2 groups, anesthetists aware of or blinded to NIRS data. The Montreal Cognitive Assessment (MoCA) was used to assess cognitive function preoperatively, immediately postoperatively, and at 2 and 6 weeks postoperatively.
Overall, 7 (17.5%) patients experienced a CDE, 5 (25%) in the aware group and 2 (10%) in the blinded group. There was no significant difference in MoCA scores between the aware and blinded groups preoperatively (27.9.1 vs. 28.2; P = .436), immediately postoperatively (26.1 vs. 26.2; P = .778), 2 weeks postoperatively (28.0 vs. 28.1; P = .737), or 6 weeks postoperatively (28.5 vs. 28.4; P = .779). There was a correlation of NIRS with systolic blood pressure (r = 0.448), diastolic blood pressure (r = 0.708), and mean arterial pressure (r = 0.608).
In our series, the incidence of CDEs was much lower than previously reported and was not lowered by use of NIRS. Patients did not have significant cognitive deficits after arthroscopic surgery in the beach chair position, and there was a correlation between NIRS and intraoperative brachial blood pressure.
Cerebral oxygenation in the beach chair position for shoulder surgery in regional anesthesia: impact on cerebral blood flow and neurobehavioral outcome
2016, Journal of Clinical Anesthesia
Citation Excerpt :
However, no differences in cognitive outcome and in serum biomarker levels (S100β, neuron-specific enolase, and glial fibrillary acidic protein) were found between the 2 groups [40]. We found no correlation between Vmax MCA or rSco2 and blood pressure at the acoustic meatus and heart level or its ratio, a ratio describing the dependency of systemic blood pressure on the degree of elevation in the BCP recently suggested by Triplet et al. [41], at any time point, further underlying the fact that systemic blood pressure is only 1 variable influencing CBF and oxygenation. We found a strong positive correlation between Vmax MCA and rSco2 values at all time points (5 minutes after BCP: r = 0.739, P > .001).
Beach chair position is considered a potential risk factor for central neurological events particularly if combined with low blood pressure. The aim of this study was to assess the impact of regional anesthesia on cerebral blood flow and neurobehavioral outcome.
This is a prospective, assessor-blinded observational study evaluating patients in the beach chair position undergoing shoulder surgery under regional anesthesia.
University hospital operating room.
Forty patients with American Society of Anesthesiologists classes I-II physical status scheduled for elective shoulder surgery.
Cerebral saturation and blood flow of the middle cerebral artery were measured prior to anesthesia and continued after beach chair positioning until discharge to the postanesthesia care unit. The anesthesiologist was blinded for these values. Controlled hypotension with systolic blood pressure ≤ 100 mm Hg was maintained during surgery.
Neurobehavioral tests and values of regional cerebral saturation, bispectral index, the mean maximal blood flow of the middle cerebral artery, and invasive blood pressure were measured prior to regional anesthesia, and measurements were repeated after placement of the patient on the beach chair position and every 20 minutes thereafter until discharge to postanesthesia care unit. The neurobehavioral tests were repeated the day after surgery.
The incidence of cerebral desaturation events was 5%. All patients had a significant blood pressure drop 5 minutes after beach chair positioning, measured at the heart as well as the acoustic meatus levels, when compared with baseline values (P < .05). There was no decrease in either the regional cerebral saturation (P = .136) or the maximal blood flow of the middle cerebral artery (P = .212) at the same time points. Some neurocognitive tests showed an impairment 24 hours after surgery (P < .001 for 2 of 3 tests).
Beach chair position in patients undergoing regional anesthesia for shoulder surgery had no major impact on cerebral blood flow and cerebral oxygenation. However, some impact on neurobehavioral outcome 24 hours after surgery was observed.

: This study was approved by the Western Institutional Review Board (Study No. 1132925).

View full text

Basic scienceAssociation between temporal mean arterial pressure and brachial noninvasive blood pressure during shoulder surgery in the beach chair position during general anesthesia

Background

Methods

Results

Conclusion

Section snippets

Materials and methods

Results

Discussion

Conclusion

Disclaimer

MRI study of cerebral blood flow and CSF flow dynamics in an upright posture: the effect of posture on the intracranial compliance and pressure

Acta Neurochir Suppl

Anesthesia for neurosurgery

Visual loss and ophthalmoplegia after shoulder surgery

Anesth Analg

Beach chair position may decrease cerebral perfusion; catastrophic outcomes have occurred

APSF Newsletter

Cardiorespiratory effects of the sitting position in neurosurgery

Br J Anaesth

The lower limit of autoregulation: time to revise our thinking?

Anesthesiology

Cardiovascular responses to postural changes: differences with age for women and men

J Clin Pharmacol

Prevalence of cerebrovascular events during shoulder surgery and association with patient position

Orthopedics

The safety of controlled hypotension for shoulder arthroscopy in the beach-chair position

J Bone Joint Surg Am

Lower limit of cerebral autoregulation questioned

APSF Newsletter

Pituitary apoplexy during general anesthesia in beach chair position for shoulder joint arthroplasty

J Anesth

Neer Award 2012: cerebral oxygenation in the beach chair position: a prospective study on the effect of general anesthesia compared with regional anesthesia and sedation

J Shoulder Elbow Surg

Circle of Willis: morphologic variation on three-dimensional time-of-flight MR angiograms

Radiology

Continuous EEG monitoring: is it ready for prime time?

Curr Opin Crit Care

Transcranial Doppler is valid for determination of the lower limit of cerebral blood flow autoregulation

Stroke

Direct cerebral vasodilatory effects of sevoflurane and isoflurane

Anesthesiology

Beach chair position, general anesthesia and deliberated hypotension during shoulder surgery: a dangerous combination!

Minerva Anestesiol

Cerebral oxygen desaturation during beach chair position

Eur J Anaesthesiol

Cerebral oxygen desaturation events assessed by near-infrared spectroscopy during shoulder arthroscopy in the beach chair and lateral decubitus positions

Anesth Analg

The effect of sevoflurane on dynamic cerebral blood flow autoregulation assessed by spectral and transfer function analysis

Anesth Analg

Preoperative estimation of cerebral blood flow autoregulation curve for control of cerebral circulation after cerebral revascularization

Resuscitation

Basic science
Association between temporal mean arterial pressure and brachial noninvasive blood pressure during shoulder surgery in the beach chair position during general anesthesia