Risk Factors for Cerebral Desaturation Events During Shoulder Surgery in the Beach Chair Position

Optimizing Visualization in Shoulder Arthroscopy: An Evidence-Based Guide

Advances in arthroscopy have contributed toward improved understanding and management of diverse pathological conditions in the shoulder. As a result, arthroscopy is often preferred by both patients and surgeons. However, surgery can be complicated by limited visualization. Techniques to improve visualization include patient and portal positioning, mechanical débridement, radiofrequency ablation, epinephrine added to irrigation fluid, tranexamic acid administration, and controlled hypotensive anesthesia. Despite published literature on each, a thorough understanding of the evidence supporting these techniques and adjuvants is essential to interpret the clinical utility of each.

Comparison of Hemodynamic Parameters Based on the Administration of Remimazolam or Sevoflurane in Patients under General Anesthesia in the Beach Chair Position: A Single-Blinded Randomized Controlled Trial

Background: We aimed to evaluate whether the administration of remimazolam as a maintenance agent for general anesthesia affects the occurrence of hypotension compared with sevoflurane when switching to the beach chair position (BCP). Methods: We conducted a prospective randomized controlled trial from June 2023 to October 2023 in adult patients undergoing orthopedic surgery under general anesthesia in the BCP. A total of 78 participants were randomly allocated to the remimazolam (R) or sevoflurane (S) groups. The primary outcome was the incidence of hypotension that occurred immediately after switching to a BCP. The secondary outcomes included differences between the study groups in perioperative blood pressure (BP), heart rate (HR), endotracheal tube extubation time, postoperative complications, and hospital length of stay (LOS). Results: The incidence of hypotension immediately after switching to a BCP was significantly higher in the S group. The risk factors associated with hypotension included sevoflurane administration and a high baseline systolic BP. In the receiver operating characteristic curve analysis for the occurrence of hypotension after the transition to a BCP, the cutoff value for systolic BP was 142 mmHg. The perioperative BP and HR were higher in the R group at several timepoints. Postoperative endotracheal tube extubation time was shorter in the R group. There were no significant differences in the postoperative complications or hospital LOS between the two groups. Conclusions: Remimazolam should be considered as an anesthetic agent to prevent hypotension when switching to BCP, and hypotension may occur frequently in patients with high baseline BP.

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.

Surgical Position of Lateral-Tilted Supine is Suitable for Proximal Humeral Fracture Operations in Geriatric Patients

OBJECTIVE

To report a new surgical position of lateral-tilted supine (LTS) for geriatric proximal humeral fracture operations.

METHODS

Between January 2016 and December 2020, we adopted the LTS position for operations in 65 geriatric patients with proximal humeral fractures.

RESULTS

Sixty-five patients including 25 males and 40 females aged 80.3 ± 8.5 years. The LTS position could be used for almost all proximal humeral fracture surgeries, such as ORIF with plate, suture anchor, and other fixation in 4 patients, open reduction and internal fixation (ORIF) with multiLoc nailing in 48, and shoulder hemiarthroplasty (SHA) in 13. Surgical position setting times were 11.47 ± 2.14 min. The systolic blood pressure changes before and after positioning were 15.07 ± 8.72 mmHg. All of the C-arm X-ray directions, including the cephalic side, contralateral side, and ipsilateral side, can be used in the LTS position surgeries. No surgical complications or no surgical position-related complications were found in these 65 cases.

CONCLUSION

The surgical position of LTS is suitable for geriatric proximal humeral fracture operations.

What Is the Risk of Intraoperative Cerebral Oxygen Desaturation in Patients Undergoing Shoulder Surgery in the Beach Chair Position?

BACKGROUND

Previous studies have shown that intraoperative cerebral desaturation in patients undergoing shoulder surgery in the beach chair position varies widely, from 0% to 80%. To our knowledge, the risk of intraoperative cerebral desaturation is not known after all identified intraoperative modifiable physiologic parameters that influence cerebral blood flow have been controlled for.

QUESTIONS/PURPOSES

(1) What is the risk of intraoperative cerebral desaturation during shoulder surgery with the patient in the beach chair position when patients received combined general anesthesia and an interscalene block, and what other factors associated with intraoperative cerebral desaturation can be identified? (2) Is intraoperative cerebral desaturation associated with 24-hour cognitive decline? (3) What factors are associated with intraoperative hypotension?

METHODS

Between April and December 2020, 51 patients underwent elective shoulder surgery in the beach chair position at one center. Nine patients were excluded: four patients refused to participate, two patients were unable to receive an interscalene brachial plexus block, and three patients were operated on in less than 70° upright position. A total of 42 patients (aged 63 ± 10 years, of whom 52% [22 of 42] were female) were prospectively recruited into this study. Each patient was diagnosed with a rotator cuff tear and underwent arthroscopic repair in the beach chair position, which was performed in an upright position of 70° to 80°. Near-infrared spectroscopy was used to monitor regional cerebral oxygen saturation. The mean arterial pressure was monitored and controlled so that it was more than 70 mmHg in patients without hypertension and within 20% from the baseline mean arterial pressure in patients with hypertension. All patients received the standardized anesthesia protocol, which consisted of an interscalene brachial plexus block and general anesthesia. Intraoperative cerebral desaturation was defined as a decrease in the regional cerebral oxygen saturation level of more than 20% from the baseline value that lasted longer than 15 seconds after induction of anesthesia. Patients' clinical characteristics such as age, sex, BMI, preoperative hemoglobin level, preexisting medical conditions, and continuing antihypertensive medications on the morning of surgery were analyzed to identify the association with intraoperative cerebral desaturation. We used the Montreal Cognitive Assessment to assess cognitive function at preoperative and 24 hours postoperative. Episodes of hypotension and its treatment after maximum head elevation were recorded. The patients' clinical characteristics were analyzed to determine their association with hypotensive events.

RESULTS

In this study, intraoperative cerebral desaturation occurred in 43% (18 of 42) of patients, and female sex was identified as an associated risk (odds ratio 4.3 [95% confidence interval 1.2 to 16.2]; p = 0.03). The median (interquartile range) duration of intraoperative cerebral desaturation was 19 minutes (5 to 38). There was no association between intraoperative cerebral desaturation and 24-hour postoperative cognitive decline (OR 0.6 [95% CI 0.1 to 2.4]; p = 0.44). Risk factors for intraoperative hypotension were a history of hypertension, regardless of whether or not the patient took antihypertensive drugs on the morning of surgery (OR 4.9 [95% CI 1.3 to 18.1]; p = 0.02), and dyslipidemia (OR 4.3 [95% CI 1.2 to 16.3]; p = 0.03).

CONCLUSION

The intraoperative cerebral desaturation risk in the beach chair position was high. Female sex was an intraoperative cerebral desaturation risk factor. However, there was no association between intraoperative cerebral desaturation and postoperative cognitive decline. Patients with hypertension and dyslipidemia are at risk of intraoperative hypotension after positioning. Further large-scale studies are required to identify intraoperative cerebral desaturation-associated adverse neurologic outcome.

LEVEL OF EVIDENCE

Level II, therapeutic study.

Frozen Shoulder 360° Release

Arthroscopic capsular release has emerged as a safe and reliable method for treating severe frozen shoulder in patients with significant loss of range of motion. This article describes a reproducible technique for arthroscopic 360° release of the shoulder performed in the lateral decubitus position.

Cost Effective Technique of Shoulder Arthroscopy Without the Use of Epinephrine in Irrigation Solution

Arthroscopic surgery of the shoulder joint and the subacromial space requires adequate visualization to be effectively performed. Visual clarity is essential to perform a safe and successful arthroscopic procedure. The major determinants to provide visualization in the subacromial space and the glenohumeral joint include adequate inflow (dependent on the dimension of the inflow cannula), flow rate versus pressure, pump system versus gravity, the use of electrocautery and radiofrequency devices, blood pressure control and hypotensive anesthesia, and the type of irrigation solution used with or without the use of epinephrine. In 2012, the cost of a 30-mL (30-mg) vial of epinephrine was $6 (adrenalin/epinephrine injection, USP, Par Pharmaceuticals), and approximately 3 to 4 bottles would be used on average for a single shoulder arthroscopy. In 2019, the same 30-mL bottle of epinephrine cost $237, a nearly 40-fold increase. The purpose of our study is to describe the various factors and techniques that can be used to maintain visual clarity in shoulder arthroscopy without the use of epinephrine in the irrigation solution and the cost savings associated without the use of epinephrine.

Editorial Commentary: "A Rush of Blood From the Head"-Predicting and Preventing Cerebral Deoxygenation During Beach-Chair Shoulder Surgery

Orthopaedic surgeons and anesthesiologists need to work together to avoid catastrophic cerebral ischemic injuries when surgery is performed with patients in the beach-chair position. Patient risk factors include body mass index but are not strongly predictive. Anesthetic management choices, such as regional anesthesia with sedation or normotensive general anesthesia with gradual and limited head elevation and hypercapnia, can significantly decrease the risk of cerebral deoxygenation.