Cerebral oxygenation in patients undergoing shoulder surgery in beach chair position: comparing general to regional anesthesia and the impact on neurobehavioral outcome

Postoperative cognitive dysfunction after beach chair positioning compared to supine position in orthopaedic surgery in the elderly

INTRODUCTION

Postoperative cognitive dysfunction (POCD) occurs in up to 26% of patients older than 60 years 1 week after non-cardiac surgery. Intraoperative beach chair positioning (BCP) is advantageous for some types of shoulder surgery. However, this kind of positioning leads to a downward bound redistribution of blood volume, with possible hypoperfusion of the brain. We hypothesized that patients > 60 years undergoing orthopaedic shoulder surgery in a BCP might experience more POCD than patients operated in the supine position (SP).

MATERIAL AND METHODS

A single-centre, prospective observational trial of 114 orthopaedic patients was performed. Study groups were established according to the type of intraoperative positioning. Anaesthesiological management was carried out similarly in both groups, including types of anaesthetics and blood pressure levels. POCD was evaluated using the Trail Making Test, the Letter-Number Span and the Regensburger Word Fluency Test. The frequency of POCD 1 week after surgery was considered primary outcome.

RESULTS

Baseline characteristics, including duration of surgery, were comparable in both groups. POCD after 1 week occurred in 10.5% of SP patients and in 21.1% of BCP patients (p = 0.123; hazard ratio 2.0 (CI 95% 0.794-5.038)). After 4 weeks, the incidence of POCD decreased (SP: 8.8% vs. BCP: 5.3%; p = 0.463). 12/18 patients with POCD showed changes in their Word Fluency Tests. Near-infrared spectroscopy (NIRS) values were not lower in patients with POCD compared to those without POCD (54% (50/61) vs. 57% (51/61); p = 0.671).

CONCLUSION

POCD at 1 week after surgery tended to occur more often in patients operated in beach chair position compared to patients in supine position without being statistically significant.

Ultrasound-guided interscalene block anesthesia performed by an orthopedic surgeon: a study of 1322 cases of shoulder surgery

Background

Interscalene blocks are becoming increasingly common for shoulder surgeries. This study primarily aimed to demonstrate the efficacy and complications and the secondarily to investigate the anesthesia-related time and patient satisfaction of an ultrasound-guided interscalene block performed by an orthopedic surgeon.

Methods

We retrospectively reviewed the medical records of 1322 consecutive patients (arthroscopic, 1225 cases; open, 97 cases) with a mean age of 64.2 years, who underwent shoulder surgery (arthroscopic or opensurgery) under an ultrasound-guided interscalene block performed by an orthopedic surgeon at a single institution between December 2012 and December 2019. We investigated patient satisfaction, block success rates, and complications and also compared the anesthesia-related time of an interscalene block with that of general anesthesia (428 cases, arthroscopic, 257 cases; open, 171 cases) for shoulder surgery with patients in the beach chair position during the same period. Difference between total anesthesia time and surgical time was defined as anesthesia-related time.

Results

Approximately 98.3% of patients were satisfied with an interscalene block, and the block success rate on the first attempt was 99.9%. Total complication incidence was 2.3%, with no recorded life-threatening complications. Anesthesia-related times were significantly shorter in the interscalene block group than those in the general anesthesia group (45 ± 14 min vs. 100 ± 26 min, P < .001).

Conclusion

An ultrasound-guided interscalene block performed by an orthopedic surgeon for shoulder surgery is effective and safe, requires less time, and has a high patient acceptance rate, making it a feasible and alternative to the block performed by anesthesiologists.

Neuromonitoring during general anesthesia in non-neurologic surgery

Cerebral complications are common in perioperative settings even in non-neurosurgical procedures. These include postoperative cognitive dysfunction or delirium as well as cerebrovascular accidents. During surgery, it is essential to ensure an adequate degree of sedation and analgesia, and at the same time, to provide hemodynamic and respiratory stability in order to minimize neurological complications. In this context, the role of neuromonitoring in the operating room is gaining interest, even in the non-neurolosurgical population. The use of multimodal neuromonitoring can potentially reduce the occurrence of adverse effects during and after surgery, and optimize the administration of anesthetic drugs. In addition to the traditional focus on monitoring hemodynamic and respiratory systems during general anesthesia, the ability to constantly monitor the activity and maintenance of brain homeostasis, creating evidence-based protocols, should also become part of the standard of care: in this challenge, neuromonitoring comes to our aid. In this review, we aim to describe the role of the main types of noninvasive neuromonitoring such as those based on electroencephalography (EEG) waves (EEG, Entropy module, Bispectral Index, Narcotrend Monitor), near-infrared spectroscopy (NIRS) based on noninvasive measurement of cerebral regional oxygenation, and Transcranial Doppler used in the perioperative settings in non-neurosurgical intervention. We also describe the advantages, disadvantage, and limitation of each monitoring technique.

Early Recognition of a Transient Ischemic Attack Utilizing Cerebral Oxygenation Monitoring During Shoulder Surgery in the Beach Chair Position: A Case Report

Shoulder surgery in the beach chair position is routinely performed, and central neurological events are rare but potentially devastating. We present a patient with transient neurological deficits after a sudden blood pressure drop with a simultaneous decrease of regional cerebral saturation values registered by cerebral oximetry. We reviewed published cases and proposed possible strategies to prevent the occurrence of similar complications in this context.

Cerebral Oxygenation in the Sitting Position Is Not Compromised During Spontaneous or Positive-Pressure Ventilation

BACKGROUND

General anesthesia with neuromuscular blockade may facilitate total shoulder arthroplasty but appears to increase risk of cerebral oxygen desaturation. Cerebral desaturation is undesirable and is a proxy for risk of stroke.

PURPOSES/QUESTIONS

This study tested the hypothesis that cerebral oxygen desaturation occurs frequently during general anesthesia with neuromuscular blockade and positive-pressure ventilation but does not occur with spontaneous ventilation. Correlations were sought among cerebral oxygen saturation, blood pressure, and cardiac index.

METHODS

We designed a prospective, observational, cohort study to measure cerebral oxygenation in 25 patients during general anesthesia, both with and without positive-pressure ventilation. Patients undergoing elective shoulder arthroplasty in the sitting position received an arterial catheter, near-infrared spectroscopic measurement of cerebral oxygenation, and non-invasive cardiac output measurement. Moderate hypotension was allowed. Blood pressure was supported as needed with ephedrine or low-dose epinephrine (but avoiding phenylephrine). Hypercapnia (45 to 55 mmHg) was targeted during positive-pressure ventilation.

RESULTS

No cerebral oxygen desaturations occurred, regardless of ventilation mode. Under positive-pressure ventilation, the median (interquartile range: Q1, Q3) cerebral oxygenation was 110% of baseline (104, 113), the mean arterial pressure was 62% of baseline (59, 69), and the cardiac index was 82% of baseline (71, 104). Cerebral oxygenation did not correlate with blood pressure or cardiac index but had moderate correlation with end-tidal carbon dioxide. No strokes occurred.

CONCLUSIONS

There were no signs of inadequate brain perfusion during general anesthesia using paralytic agents. Positive-pressure ventilation with moderate hypotension in the sitting position does not endanger patients, in the context of moderate hypercapnia and hemodynamic support using ephedrine or epinephrine.

The beach chair position for shoulder surgery in intravenous general anesthesia and controlled hypotension: Impact on cerebral oxygenation, cerebral blood flow and neurobehavioral outcome

STUDY OBJECTIVES

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.

DESIGN

Prospective, assessor-blinded observational study.

SETTING

University hospital, shoulder surgery operating room.

PATIENTS

Forty ASA I-II patients scheduled for shoulder surgery in beach chair position and controlled hypotension.

INTERVENTIONS

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.

MEASUREMENTS

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.

MAIN RESULTS

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).

CONCLUSIONS

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.

Cerebral near-infrared spectroscopy (NIRS) for perioperative monitoring of brain oxygenation in children and adults

BACKGROUND

Various techniques have been employed for the early detection of perioperative cerebral ischaemia and hypoxia. Cerebral near-infrared spectroscopy (NIRS) is increasingly used in this clinical scenario to monitor brain oxygenation. However, it is unknown whether perioperative cerebral NIRS monitoring and the subsequent treatment strategies are of benefit to patients.

OBJECTIVES

To assess the effects of perioperative cerebral NIRS monitoring and corresponding treatment strategies in adults and children, compared with blinded or no cerebral oxygenation monitoring, or cerebral oxygenation monitoring based on non-NIRS technologies, on the detection of cerebral oxygen desaturation events (CDEs), neurological outcomes, non-neurological outcomes and socioeconomic impact (including cost of hospitalization and length of hospital stay).

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL 2016, Issue 12), Embase (1974 to 20 December 2016) and MEDLINE (PubMed) (1975 to 20 December 2016). We also searched the World Health Organization (WHO) International Clinical Trials Registry Platform for ongoing studies on 20 December 2016. We updated this search in November 2017, but these results have not yet been incorporated in the review. We imposed no language restriction.

SELECTION CRITERIA

We included all relevant randomized controlled trials (RCTs) dealing with the use of cerebral NIRS in the perioperative setting (during the operation and within 72 hours after the operation), including the operating room, the postanaesthesia care unit and the intensive care unit.

DATA COLLECTION AND ANALYSIS

Two authors independently selected studies, assessed risk of bias and extracted data. For binary outcomes, we calculated the risk ratio (RR) and its 95% confidence interval (CI). For continuous data, we estimated the mean difference (MD) between groups and its 95% CI. As we expected clinical and methodological heterogeneity between studies, we employed a random-effects model for analyses and we examined the data for heterogeneity (I2 statistic). We created a 'Summary of findings' table using GRADEpro.

MAIN RESULTS

We included 15 studies in the review, comprising a total of 1822 adult participants. There are 12 studies awaiting classification, and eight ongoing studies.None of the 15 included studies considered the paediatric population. Four studies were conducted in the abdominal and orthopaedic surgery setting (lumbar spine, or knee and hip replacement), one study in the carotid endarterectomy setting, and the remaining 10 studies in the aortic or cardiac surgery setting. The main sources of bias in the included studies related to potential conflict of interest from industry sponsorship, unclear blinding status or missing participant data.Two studies with 312 participants considered postoperative neurological injury, however no pooled effect estimate could be calculated due to discordant direction of effect between studies (low-quality evidence). One study (N = 126) in participants undergoing major abdominal surgery reported that 4/66 participants experienced neurological injury with blinded monitoring versus 0/56 in the active monitoring group. A second study (N = 195) in participants having coronary artery bypass surgery reported that 1/96 participants experienced neurological injury in the blinded monitoring group compared with 4/94 participants in the active monitoring group.We are uncertain whether active cerebral NIRS monitoring has an important effect on the risk of postoperative stroke because of the low number of events and wide confidence interval (RR 0.25, 95% CI 0.03 to 2.20; 2 studies, 240 participants; low-quality evidence).We are uncertain whether active cerebral NIRS monitoring has an important effect on postoperative delirium because of the wide confidence interval (RR 0.63, 95% CI 0.27 to 1.45; 1 study, 190 participants; low-quality evidence).Two studies with 126 participants showed that active cerebral NIRS monitoring may reduce the incidence of mild postoperative cognitive dysfunction (POCD) as defined by the original studies at one week after surgery (RR 0.53, 95% CI 0.30 to 0.95, I2 = 49%, low-quality evidence).Based on six studies with 962 participants, there was moderate-quality evidence that active cerebral oxygenation monitoring probably does not decrease the occurrence of POCD (decline in cognitive function) at one week after surgery (RR 0.62, 95% CI 0.37 to 1.04, I2 = 80%). The different type of monitoring equipment in one study could potentially be the cause of the heterogeneity.We are uncertain whether active cerebral NIRS monitoring has an important effect on intraoperative mortality or postoperative mortality because of the low number of events and wide confidence interval (RR 0.63, 95% CI 0.08 to 5.03, I2= 0%; 3 studies, 390 participants; low-quality evidence). There was no evidence to determine whether routine use of NIRS-based cerebral oxygenation monitoring causes adverse effects.

AUTHORS' CONCLUSIONS

The effects of perioperative active cerebral NIRS monitoring of brain oxygenation in adults for reducing the occurrence of short-term, mild POCD are uncertain due to the low quality of the evidence. There is uncertainty as to whether active cerebral NIRS monitoring has an important effect on postoperative stroke, delirium or death because of the low number of events and wide confidence intervals. The conclusions of this review may change when the eight ongoing studies are published and the 12 studies awaiting assessment are classified. More RCTs performed in the paediatric population and high-risk patients undergoing non-cardiac surgery (e.g. neurosurgery, carotid endarterectomy and other surgery) are needed.

Spinal versus general anesthesia for lumbar spine surgery in high risk patients: Perioperative hemodynamic stability, complications and costs

OBJECTIVE

More stable perioperative hemodynamic conditions, lower costs and a lower perioperative complication rate were reported in young healthy patients undergoing lumbar spine surgery in spinal anesthesia (SA) compared to general anesthesia (GA). However, the benefits of SA in high risk patients (ASA≥II suffering from cardiovascular and/or pulmonary pathologies) undergoing this surgery are unclear. Our objective was to analyze whether SA leads to an improved perioperative hemodynamic stability and to a more cost-effective management compared to GA in high risk patients undergoing this surgery.

METHODS

In a retrospective analysis 146 ASA II-III patients who underwent lumbar spine surgery in SA were compared with 292 ASA I-III patients who were operated in GA between 2000 and 2014. Hemodynamic effects, hospitalization times, complications, and costs according to the Swiss billing system were assessed. The data extraction was conducted according to Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) initiative for cohort studies.

RESULTS

The patients in the SA group were older (75years (±9.6) vs 69 (±11.5), p<0.001), had a lower BMI (25.8kg/m2 (±4.8) vs 27.2 (±4.7), p=0.003) and showed a higher ASA score (3 vs 2, p<0.001). However, SA was associated with significantly better perioperative hemodynamic stability with less need for intraoperative vasopressors (15% vs 57%, p<0.001), volume supplementation (1113ml ±458 vs 1589±644, p<0.001) and transfusions (0% vs 4%, p<0.001). Additionally, the number of hypotension episodes was lower in the SA group (15% vs 47%, p<0.001). Furthermore, the SA group showed a significantly shorter duration of surgery (70min (±1.2) vs 91 (±41), p<0.001), lower postoperative nausea and vomiting (PONV) (4% vs 28%, p<0.001) and pain in the post anesthesia care unit (PACU) (visual analogue scale (VAS) 2.3 (±1.1) vs 0.8 (±0.8), p<0.001), whereas pain after 24h did not differ (VAS 0.9 (±1) vs 0.8 (±1.1), p=ns). The postoperative complication (7% vs 5%, p=0.286) and revision rates (4% vs 5%, p=0.626) were similar in both groups. Total costs (United States Dollars (USD) 6377 (±2332) vs 7018 (±4056), p=0.003) and PACU time were significantly lower in the SA group (35min (±12) vs 109 (±173), p<0.001).

CONCLUSIONS

Lumbar spine surgery in cardiovascular high risk patients with SA is safe, allows good perioperative hemodynamic stability and might lead to lower health care costs. Further prospective studies are needed to confirm these findings.

Cerebral desaturation events in the beach chair position: correlation of noninvasive blood pressure and estimated temporal mean arterial pressure

BACKGROUND

Cerebral oximetry (rSO2) has emerged as an important tool for monitoring of cerebral perfusion during surgery. High rates of cerebral desaturation events (CDEs) have been reported during surgery in the beach chair position. However, correlations have not been made with blood pressure measured at the cerebral level. The purpose of this study was to examine the correlations between brachial noninvasive blood pressure (NIBP) and estimated temporal mean arterial pressure (eTMAP) during CDEs in the beach chair position.

METHODS

Fifty-seven patients underwent elective shoulder surgery in the beach chair position. Values for eTMAP, NIBP, and rSO2 were recorded supine (0°) after induction and when a CDE occurred in the 70° beach chair position. Twenty-six patients experienced 45 CDEs, defined as a 20% drop in rSO2 from baseline.

RESULTS

Median reduction in NIBP, eTMAP, and rSO2 from baseline to the CDE were 48.2%, 75.5%, and 33.3%, respectively. At baseline, there was a significant weak negative correlation between rSO2 and NIBP (rs = -0.300; P = .045) and no significant association between rSO2 and eTMAP (rs = -0.202; P = .183). During CDEs, there were no significant correlations between rSO2 and NIBP (rs = -0.240; P = .112) or between rSO2 and eTMAP (rs = -0.190; P = .212). No significant correlation between the decrease in rSO2 and NIBP (rs = 0.064; P = .675) or between rSO2 and eTMAP (rs = 0.121; P = .430) from baseline to CDE was found.

CONCLUSION

NIBP and eTMAP are unreliable methods for identifying a CDE in the beach chair position. Cerebral oximetry provides additional information to the values obtained from NIBP and eTMAP, and all should be considered independently and collectively.

A comparison of the lateral decubitus and beach-chair positions for shoulder surgery: advantages and complications

Arthroscopic or open shoulder surgery can be performed using the lateral decubitus or beach-chair position. Advantages of the lateral decubitus position include better visualization and instrument access for certain procedures and decreased risk for cerebral hypoperfusion. Complications associated with this position include traction injuries, resulting in neurapraxia, thromboembolic events, difficulty with airway management, and the potential need to convert to an anterior open approach. One advantage of the beach-chair position is easier setup from a supine to upright position, which allows the surgeon the option to convert to an open procedure if necessary. Although rare, patients in this position may experience cerebral hypoperfusion and complications that range from cranial nerve injury to infarction. Other complications related to this position include cervical traction neurapraxia, blindness, and cardiac and embolic events. The surgeon must be cognizant of the complications associated with both positions and take extra care in the initial patient setup and coordination with the anesthesiologist to minimize the risk of complications and morbidity.