Cerebrovascular assessment of patients undergoing shoulder surgery in beach chair position using a multiparameter transcranial Doppler approach

Abstract

Although the beach-chair position (BCP) is widely used during shoulder surgery, it has been reported to associate with a reduction in cerebral blood flow, oxygenation, and risk of brain ischaemia. We assessed cerebral haemodynamics using a multiparameter transcranial Doppler-derived approach in patients undergoing shoulder surgery. 23 anaesthetised patients (propofol (2 mg/kg)) without history of neurologic pathology undergoing elective shoulder surgery were included. Arterial blood pressure (ABP, monitored with a finger-cuff plethysmograph calibrated at the auditory meatus level) and cerebral blood flow velocity (FV, monitored in the middle cerebral artery) were recorded in supine and in BCP. All subjects underwent interscalene block ipsilateral to the side of FV measurement. We evaluated non-invasive intracranial pressure (nICP) and cerebral perfusion pressure (nCPP) calculated with a black-box mathematical model; critical closing pressure (CrCP); diastolic closing margin (DCM—pressure reserve available to avoid diastolic flow cessation); cerebral autoregulation index (Mxa); pulsatility index (PI). Significant changes occured for DCM [mean decrease of 6.43 mm Hg (p = 0.01)] and PI [mean increase of 0.11 (p = 0.05)]. ABP, FV, nICP, nCPP and CrCP showed a decreasing trend. Cerebral autoregulation was dysfunctional (Mxa > 0.3) and PI deviated from normal ranges (PI > 0.8) in both phases. ABP and nCPP values were low (< 60 mm Hg) in both phases. Changes between phases did not result in CrCP reaching diastolic ABP, therefore DCM did not reach critical values (≤ 0 mm Hg). BCP resulted in significant cerebral haemodynamic changes. If left untreated, reduction in cerebral blood flow may result in brain ischaemia and post-operative neurologic deficit.

Closed-loop target-controlled infusion system for propofol guided by bispectral index applied in patients undergoing shoulder arthroscopy in the beach chair position- a randomized controlled trial

“…Previous studies have shown that there is a significant decrease in BIS values in head-up position compared with neutral position during general anesthesia [9]. It means that patient's position during anesthesia may affect the BIS values, which may be related to decrease cerebral blood flow [5]. Brain ischemia and transient visual loss caused by decreased cerebral blood flow have been documented in patients who have undergone shoulder surgery in the beach chair position [10][11][12][13][14][15]position.…”

“…After placement of beach chair position, the patient's head and neck form an angle of 90°~110° with the horizontal position. Danilo et al [5] found cerebral perfusion decreased in the beach chair position by using a multiparameter transcranial Doppler-derived approach in patients underwent shoulder surgery. Changes in intracranial blood flow may cause changes in EEG signals and EEG waveform.…”

Journal of Clinical Monitoring and Computing 2019 end of year summary: monitoring tissue oxygenation and perfusion and its autoregulation

“…In the August 2019 issue, Cardim et al [15] investigated cerebral hemodynamics in patients (n = 23) undergoing shoulder surgery in the beach-chair position (BCP). In BCP, the cranial part of the operating table is tilted to an angle between 45-90° (also called sitting position), so that the shoulder is optimally exposed to the surgical team.…”

Could Interscalene Block Possibly be Protective Against Cerebral Ischemia During Shoulder Surgery in a Beach Chair Position?

“…Arthroscopic shoulder surgeries are usually performed in a sitting position. Many studies report rare but significant neurological injuries such as stroke, spinal cord ischemia, and temporary vision loss in the beach chair position [ 5 ]. The incidence of neurologic complications in the beach chair position remains unknown.…”

“…The incidence of neurologic complications in the beach chair position remains unknown. However, some studies have shown that 0.0004% of such patients have a major stroke [ 5 ]. These neurologic complications were reported after shoulder surgery in the beach chair position (BCP) due to hypotension and head above the heart level, perhaps due to cerebral autoregulation failure and cerebral ischemia as a result of decreased cerebral perfusion.…”