Lumbar spine surgery positioning complications: a systematic review

Endoscopic Posterior Cervical Foraminotomy Under Lateral Decubitus Position with Local Anesthesia

BACKGROUND

Endoscopic posterior cervical foraminotomy is gaining popularity among endoscopic spine surgeons for the treatment of radiculopathy caused by foraminal stenosis.

METHODS

This study describes a technique using the lateral decubitus position for endoscopic posterior cervical foraminotomy under monitored anesthesia care and local anesthesia only.

RESULTS

A total of 10 patients with contraindications to general anesthesia underwent the procedure, resulting in improvement in cervical radicular pain with no perioperative complications.

CONCLUSIONS

The findings suggest that this approach is a viable alternative for patients at high risk of general anesthesia care, expanding the surgical options for the treatment of radiculopathy.

The Optimal Patient Position on the Surgical Table for Lateral Lumbar Interbody Fusion in Adult Spinal Deformity Using Three-Dimensional Computed Tomography: A Retrospective Study

Introduction

Lateral lumbar interbody fusion (LLIF) techniques have been extensively used in adult spinal deformity surgery. Preoperative knowledge of the optimal position of the patient on the surgical table is essential for a safe procedure. Therefore, this study aims to determine the optimal angle for positioning the patient on the surgical table during LLIF using three-dimensional computed tomography (3DCT).

Methods

Data from 59 patients (2 males, 57 females, mean age 66.3±8.6 years) with adult spinal deformities treated by performing corrective spinal surgery were included in this observational retrospective study. Simulated fluoroscopic images were obtained using 3DCT images rotated from the reference position with the spinous process of S1 as the midline to the position with the spinous process in the center of the bilateral pedicle of T12-L5. The rotation angle of each vertebra was measured and defined as the optimal rotation angle (ORA). The angle that bisected the angle between the maximum and minimum ORA was defined as the optimal mean angle of the maximum and minimum ORA (OMA) and considered the optimal angle for the patient's position on the surgical table, as this position could minimize the rotation angle of the surgical table during surgery. A multiple regression analysis was performed to predict OMA.

Results

Multiple regression analysis revealed the following equation: OMA=1.959+(0.238×lumbar coronal Cobb angle)+(-0.208×sagittal vertical axis).

Conclusions

When the patient is placed on the surgical table by rotating them at the OMA, the rotation of the surgical table can be reduced, ensuring a safe and efficient surgical procedure.

Intra-abdominal Content Movement in Prone Versus Lateral Decubitus Position Lateral Lumbar Interbody Fusion (LLIF)

STUDY DESIGN

A prospective, anatomical imaging study of healthy volunteer subjects in accurate surgical positions.

OBJECTIVE

To establish if there is a change in the position of the abdominal contents in the lateral decubitus (LD) versus prone position.

SUMMARY OF BACKGROUND DATA

Lateral transpsoas lumbar interbody fusion (LLIF) in the LD position has been validated anatomically and for procedural safety, specifically in relation to visceral risks. Recently, LLIF with the patient in the prone position has been suggested as an alternative to LLIF in the LD position.

MATERIALS AND METHODS

Subjects underwent magnetic resonance imaging of the lumbosacral region in the right LD position with the hips flexed and the prone position with the legs extended. Anatomical measurements were performed on axial magnetic resonance images at the L4-5 disc space.

RESULTS

Thirty-four subjects were included. The distance from the skin to the lateral disc surface was 134.9 mm in prone compared with 118.7 mm in LD ( P <0.0001). The distance between the posterior aspect of the disc and the colon was 20.3 mm in the prone compared with 41.1 mm in LD ( P <0.0001). The colon migrated more posteriorly in relation to the anterior margin of the psoas in the prone compared with LD (21.7  vs . 5.5 mm, respectively; P <0.0001). 100% of subjects had posterior migration of the colon in the prone compared with the LD position, as measured by the distance from the quadratum lumborum to the colon (44.4  vs . 20.5 mm, respectively; P <0.001).

CONCLUSION

There were profound changes in the position of visceral structures between the prone and LD patient positions in relation to the LLIF approach corridor. Compared with LD LLIF, the prone position results in a longer surgical corridor with a substantially smaller working window free of the colon, as evidenced by the significant and uniform posterior migration of the colon. Surgeons should be aware of the potential for increased visceral risks when performing LLIF in the prone position.

LEVEL OF EVIDENCE

Level II-prospective anatomical cohort study.

The Challenges of Spinal Surgery Requiring Ventral Decubitus in the Critical Trauma Patient on Extracorporeal Membrane Oxygenation: A Case Report

Extracorporeal membrane oxygenation (ECMO) provides a bypass of the lungs, ensuring blood oxygenation and carbon dioxide removal in cases of respiratory failure. The nature of the device itself creates many perioperative challenges, including fluid management and the management of anticoagulation. Surgery via the posterior approach for an unstable spinal fracture requiring the ventral decubitus position comes with its own set of difficulties, among which are the need for stability and craniocaudal alignment when rotating the patient, the risk of increased abdominal pressure, and the damage to vulnerable soft tissues like the eyes, nose, and others. The combination of these two situations creates a synergistic effect, which adds to the difficulty of the management of the situation and requires a personalized, multidisciplinary approach. We present a case of a critical trauma patient who was on venovenous ECMO as a consequence of refractory respiratory hypoxemia with an unstable mid-thoracic spinal fracture requiring surgical intervention via the posterior approach (demanding intra-operative ventral decubitus).

Guidelines in Practice: Positioning the Patient

Positioning the patient is an important perioperative task; the recently updated AORN "Guideline for positioning the patient" provides perioperative personnel with background information and evidence-based best practices for perioperative patient positioning and focuses on maintaining patient and staff member safety. The revised guideline includes recommendations for placing patients safely in a variety of positions and avoiding positioning injuries, such as postoperative vision loss. This article provides an overview of positioning recommendations for assessing patients' risk for injury, implementing safe positioning practices, placing patients in the Trendelenburg position, and preventing intraocular injuries. It also includes a patient-focused scenario on preventing adverse events associated with the Trendelenburg position that aligns with information discussed in the article. Perioperative nurses should review the guideline in its entirety and implement appropriate recommendations for positioning patients during procedures.

Anterior To Psoas lumbar and lumbosacral combined with posterior reconstruction in Adult Spinal Deformity: A bicentric European study

Introduction

Lateral lumbar fusion via the trans-psoas approach is popular in adult deformity reconstruction. To overcome its limitations (neurological damage to the plexus and lack of applicability to the lumbosacral junction), a modified anterior-to-psoas (ATP) approach has been described and used.

Research question

To investigate the results of ATP lumbar and lumbosacral fusion, in a cohort of adult patients treated with combined anteroposterior approaches for adult spinal deformity (ASD).

Materials and methods

ASD patients surgically treated at two tertiary spinal centres were followed up. Forty patients were treated with combined ATP and posterior surgery: 11 with open lumbar lateral interbody-fusions (lumbotomy LLIF) and 29 with lesser invasive oblique lateral interbody-fusions (OLIF). Preoperative demographics, aetiology, clinical characteristics, and spinopelvic parameters were comparable between the two cohorts.

Results

At a minimum 2-year follow-up, both cohorts showed significant improvements in patient reported outcome measures (PROMs), i.e. Visual Analogue Scale and Core Outcome Measures Index, as well as radiological parameters, with no significant differences based on the type of surgical approach. No significant differences were found in major (P ​= ​0.457) and minor (P ​= ​0.071) complications between the two cohorts.

Discusson and conclusion

Anterolateral lumbar interbody fusions, whether performed via a direct or oblique approach, proved to be safe and effective adjuvants to posterior surgery in patients with ASD. No significant complication differences were noted between techniques. In addition, the anterior-to-psoas approaches limited the risks of post-operative pseudoarthrosis by providing solid anterior support to lumbar and lumbosacral segments, demonstrating a positive impact on PROMS.

Comparison of pain and discomfort in supine and lateral positions after surgery for lumbar degenerative disease: A prospective randomized controlled study

INTRODUCTION

To compare postoperative pain and discomfort between supine and lateral positions after lumbar surgery, a prospective randomized controlled study was performed.

METHODS

Forty-three patients with lumbar degenerative disease, treated by decompression (n = 23) or fusion surgery (n = 20), were randomly assigned to be placed in either the supine (supine group: n = 21) or lateral (lateral group: n = 22) position postoperatively, and asked to maintain their position until a day after the surgery. Postoperative back pain and discomfort (visual analog scale [VAS], 0-100 mm) and the number of patients who could maintain their position were examined.

RESULTS

The VAS scores for back pain (supine: 64.9 ± 22.0, lateral: 55.7 ± 21.4) showed no significant difference between the positions. However, the supine group showed significantly more severe discomfort (75.6 ± 15.7) than the lateral group (64.9 ± 15.7, p = 0.039). Significantly fewer patients maintained their position in the supine group (28.2%) than in the lateral group (68.2%; p = 0.022). Among patients who underwent fusion surgery, significantly fewer patients maintained their position in the supine group (10.0%) than those in the lateral group (60.0%, p = 0.029).

CONCLUSION

Postoperative discomfort was significantly reduced in the lateral position than in the supine position; thus, the lateral position is more suitable after lumbar surgery in terms of postoperative discomfort.

Resection of disseminated recurrent myxopapillary ependymoma with more than 4-year follow-up: operative nuance for prolonged prone position. Illustrative case

BACKGROUND

Symptomatic disseminated myxopapillary ependymoma (MPE) in a young person presents a daunting challenge because the risks of prolonged prone positioning and spinal cord injury may outweigh the likelihood of attaining the benefit of gross total resection.

OBSERVATIONS

The authors reported the case of a 15-year-old girl with five discrete recurrent spinal cord ependymomas. The patient received a 25-hour surgical procedure for gross total resection of the tumors and fusion over an approximately 33-hour period. She experienced complete resolution of all preoperative neurological symptoms and subsequently received adjuvant radiation therapy. At 52 months after surgery, she was still experiencing neurologically intact, progression-free survival. This case illustrated one of the most extensive recurrent tumor resections for MPE with prolonged disease-free survival reported to date. It may also represent the longest prone position spinal case reported and was notable for a lack of any of the complications commonly associated with the prolonged prone position.

LESSONS

The authors discussed the complexity of surgical decision-making in a symptomatic patient with multiple disseminated metastases, technical considerations for resection of intradural and intramedullary spinal cord tumors, and considerations for avoiding complications during prolonged positioning necessary for spinal surgery.

Surgical management of lumbar spinal stenosis in patients over 80: is there an increased risk?

Management of lumbar spinal stenosis (LSS) represents the first cause of spinal surgery for the elderly and will increase with the aging population. Although the surgery improves quality of life, the procedure involves anaesthetic and operative risks. The aim of this study was to assess whether the postoperative complication rate was higher for elderly patients and to find confounding factors. We conducted a retrospective study including all LSS surgeries between 2012 and 2020 at the University Hospital of Caen. We compared two populations opposing patients aged over 80 with others. The primary endpoint was the occurrence of a severe complication (SC). Minor complications were the secondary endpoint. Comorbidities, history of lumbar spine surgery and surgical characteristics were recorded. Nine hundred ninety-six patients undergoing surgery for degenerative LSS were identified. Patients over 80 were significantly affected by additional comorbidities: hypertension, heart diseases, higher age-adjusted comorbidity Charlson score, ASA score and use of anticoagulants. Knee-chest position was preferred for younger patients. Older patients underwent a more extensive decompression and had more incidental durotomies. Of the patients, 5.2% presented SC. Age over 80 did not appear to be a significant risk factor for SC, but minor complications increased. Multivariate analysis showed that heart diseases, history of laminectomy, AA-CCI and accidental durotomies were independent risk factors for SC. Surgical management for lumbar spinal stenosis is not associated to a higher rate of severe complications for patients over 80 years of age. However, preoperative risk factors should be investigated to warn the elderly patients that the complication risk is increased although an optimal preparation is the way to avoid them.

Patient-Customised Theatre Mattress Supports for Spinal Surgery: A Pilot Study Presenting a Novel Engineering Virtual Design and Manufacturing Technique

Optimal patient positioning for spine surgery is vital for surgical success and the minimisation of complications intra-/post-operatively. In patients with complex co-morbidities, commercially available surgical positioning equipment is inadequate. To overcome this, a novel method was developed to create custom-fit patient-specific theatre mattresses for patients undergoing spine surgery. An innovative digital workflow involving 3D surface scanning, 3D simulation and computer aided design was developed to manufacture customised theatre supports with patient-specific requirements. These supports offered the surgeon an enhanced ability to relieve load bearing on prominent anatomical features or where desired, to tailor the support surface to the patient's anatomy for lengthy surgery. The bespoke theatre mattress was evaluated by whether the support resulted in a complication-free surgery. Using this new workflow, case examples for two patients with complex co-morbidities were described. The spine surgeon and anaesthetist reported the patient-specific custom mattresses were fit as per the required design, provided sufficient clearance around anatomical prominences and areas that required to be unloaded, had sufficient clearance for the anaesthetic method and cannulation, provided excellent surgical access and stability during surgery, and postoperatively no soft tissue overload over bony prominence and implanted devices. Positive patient outcomes after successful lengthy surgical interventions were associated with these patient-specific, contoured mattress supports. Future projects will seek to utilise this technology for other types of surgeries and intra-operative positioning requirements, and for a broader demographic of patients in both the paediatric and adult setting.

Prone Positioning as a Potential Risk Factor for Deep Vein Thrombosis in COVID-19 Patients: A Hypothesis Generating Observation

Aims of the study: Virchow’s triad with stasis, activated coagulation, and endothelial damage is common in SARS-CoV2. Therefore, we sought to retrospectively assess whether the duration of prone position may serve as a risk factor for deep vein thrombosis in critically ill patients. Methods: In this single center retrospective study of a tertiary referral hospital, patients with acute respiratory distress syndrome (ARDS) due to COVID-19 pneumonia admitted to critical care underwent venous ultrasound screening for deep vein thrombosis (DVT). Data on DVT diagnosis, duration of prone positioning, demographic, respiratory, and laboratory parameters were retrospectively collected and compared between DVT and non-DVT patients. Results: 21 patients with ARDS from COVID-19 pneumonia were analyzed. DVT was detected in 11 (52%) patients (76.2% male, median age 64 (58; 68.5) years, median body mass index 31 (27; 33.8) kg/m²). In patients diagnosed with DVT, median prone ventilation had been maintained twice as long as compared to patients without DVT (57 (19; 72) versus 28 (0; 56.3) h, p = 0.227) on ICU day 5 with a trend towards longer prone position time (71 (19; 104) versus 28 (0; 73) h, p = 0.06) on ICU day 7. Conclusions: Prone ventilation and constitutional factors may constitute an additional risk factor for DVT in COVID-19 patients. Since recent studies have shown that therapeutic anticoagulation does not impact the occurrence of thromboembolic events, it may be worthwhile to consider mechanical factors potentially affecting blood flow stasis in this high-risk population. However, due to the limited number of patients, our observations should only be considered as hypothesis-generating. Future studies, sufficiently powered and preferably prospective, will be needed to confirm our hypothesis.

A practical guide to patient position and complication management in neurosurgery: a systematic qualitative review

PURPOSE

Adequate patient positioning is of paramount importance in neurosurgery. Complications related to the position are common and make up for more than 16% of the claims towards anaesthesiologists and neurosurgeons. This paper aims to provide the anaesthesiologist with a practical guide to avoid common pitfalls related to the patient positioning process.

METHOD

We performed a systematic review of the medical literature for the identification, screening, and inclusion of articles. The bibliographic search was conducted on June 1st, 2021 by two of the authors. In this review, we included articles indexed by MEDLINE, Cochrane Library, or Google Scholar.

RESULTS

We retrieved a total of 5706 unique papers from our initial search. However, after the initial screening, 5363 papers were removed is not related to our research leaving a total of 343 papers. We examined the full text of all the 343 articles including 68 of them in the final qualitative analysis.

DISCUSSION

In this review we examine the most common neurosurgical positions: supine, sitting, lateral, park-bench, prone, jack-knife, and knee-chest. For each of them, the proper positioning and related complications are described. Particular attention is given to the prevention and management of these complications, providing a practical guide for clinicians.

Perioperative Care of Patients Undergoing Major Complex Spinal Instrumentation Surgery: Clinical Practice Guidelines From the Society for Neuroscience in Anesthesiology and Critical Care

Evidence-based standardization of the perioperative management of patients undergoing complex spine surgery can improve outcomes such as enhanced patient satisfaction, reduced intensive care and hospital length of stay, and reduced costs. The Society for Neuroscience in Anesthesiology and Critical Care (SNACC) tasked an expert group to review existing evidence and generate recommendations for the perioperative management of patients undergoing complex spine surgery, defined as surgery on 2 or more thoracic and/or lumbar spine levels. Institutional clinical management protocols can be constructed based on the elements included in these clinical practice guidelines, and the evidence presented.

Risk Factors for Facial Pressure Ulcers in Patients Who Underwent Prolonged Prone Orthopedic Spine Surgery

MINI

This study evaluated incidence and risk factors associated with the development of facial pressure ulcers (FPU) in patients who underwent spine surgery in prone position. A total of 300 cases were studied. The incidence of FPU after prone spine surgery using head padded device >3 hours was 27.3%. Hypotension, higher temperature, prolonged operation time, and much crystalloid therapy were the independent risk factors.

Risk factors of meralgia paresthetica after prone position surgery: Possible influence of operating position, laminectomy level, and preoperative thoracic kyphosis

Obesity and a prolonged surgical duration are reported risk factors for meralgia paresthetica (MP) after prone position surgery; however, this fails to explain why MP seldom occurs after prone position craniotomy. We reviewed the incidence of MP after spinal surgery and craniotomy in the prone position and investigated whether unidentified factors are involved in the mechanism of postoperative MP. Between January 2014 and March 2020, we performed 556 prone position surgeries. We excluded patients aged ≤16 years and those who were comatose or who required redo-surgery, and reviewed 446 eligible patients (124 who underwent craniotomies and 322 who underwent posterior spinal surgeries). Postoperative MP occurred in 46 (10.3%) patients with a higher incidence after spinal surgery than after craniotomy (13.7% vs. 1.6%, p < 0.001). Among the 322 patients who received posterior spinal surgery, thoracic and lumbar laminectomies were associated with a higher incidence of MP than cervical laminectomy. Analyses limited to those patients who received thoracic and lumbar laminectomies revealed that the preoperative thoracic kyphosis (TK) angle was significantly greater in patients with MP than in those without MP (average TK angle, 38.9° vs. 23.1°; p < 0.001), and that the preoperative lumbar lordosis angle did not significantly differ between the two groups. Apart from the known predisposing factors, we found that thoracolumbar-sacral laminectomy in patients with a greater TK angle is also a risk factor for MP after prone position surgery.

Perioperative concerns in Pott's spine: A review

Pott's disease is the most common granulomatous spine infection caused by tubercle bacilli and is a common site of osseous tuberculosis, accounting for 50–60% of cases. The delay in establishing diagnosis and management results in complications such as spinal cord compression and spinal deformity. The aim of this narrative review is to discuss the perioperative concerns in patients for spine surgery. The literature source for this review was obtained via PubMed, Medline, Google Scholar, Cochrane database of systematic reviews, and textbooks until December 2019. On the literature search, we could not retrieve any review article specifically discussing the perioperative concerns of spinal tuberculosis. Therefore, the aim of the present narrative review is to discuss the perioperative concerns of patients for spine surgery along with the specific concerns related to spinal tuberculosis.

Hereditary spherocytosis: a risk factor for thigh pressure myonecrosis in posterior spine surgery

The objective of this study was to make surgeons aware of a potential pressure complication in posterior spine surgery for patients with hereditary spherocytosis (HS) and to present a plausible hypothesis for injury. Posterior spine surgery is common practice for adolescent idiopathic scoliosis (AIS). Common, less severe surgical risks include pressure ulcers; while rare, more severe pressure complications include rhabdomyolysis and compartment syndrome. In patients with HS, a familial hemolytic disorder with altered red cell deformability, it is unknown if their red cell disorder is an additional risk factor for pressure-related surgical injuries. Two patients with HS, an 18-year-old male and a 17-year-old female, were both post-splenectomy and underwent revision posterior spinal fusion and instrumentation for progressive AIS. Surgery lasted 9 hours and 7 hours respectively, with no intraoperative complications other than prolonged surgical time due to revision nature of the deformities. Thigh redness and swelling was noted in both patients directly deep to the thigh pads. Thigh myonecrosis was diagnosed with eventual recovery in both cases. Patients with HS may be at inherent more risk of pressure complications during posterior spine surgery. We propose that thigh myonecrosis occurs with decreased perfusion and hemolysis from HS erythrocytes' inherent fragility, decreased deformability within capillaries, and prolonged microvasculature compression from positioning, causing poor microvascular perfusion, tissue ischemia, and reperfusion injury. Level of veidence: IV.

Reducing the Risk and Impact of Brachial Plexus Injury Sustained From Prone Positioning-A Clinical Commentary

INTRODUCTION

Prone positioning is deployed as a critical treatment for improving oxygenation in patients with Acute Respiratory Distress Syndrome. This regimen is currently highly prevalent in the COVID-19 pandemic. The pandemic has brought about increased concern about how best to safely avoid brachial plexus injuries when caring for unconscious proned patients.

METHODS

A review of the published literature on brachial plexus injuries secondary to proning ventilated patients was performed. This was combined with a review of available international critical care guidelines in order to produce a succinct set of guidelines to aid critical care departments in reducing brachial plexus injuries during these challenging times.

DISCUSSION

There is no one manner in which prone positioning an unconscious patient can be made universally safe. This paper provides 6 key steps to reducing the incidence of brachial plexus injuries while proning and suggests a safe and sensible management and referral pathway for the conscious patient in which a brachial plexus injury is identified.

CONCLUSION

There is in truth no completely safe position for every patient and certainly there will be anomalies in anatomy that will predispose certain individuals to nerve injury. Thus the injury rate cannot be reduced to zero but an understanding of the principles of protection will inform those undertaking positioning.

EVALUATION OF INTERBODY FUSION TWO YEARS AFTER LLIF PROCEDURE

ABSTRACT Objectives The LLIF technique, extreme lateral interbody fusion, reaches the disc laterally through the psoas muscle, offering adequate access to the disc space with the added benefit of preventing iatrogenic injury to abdominal vascular structures (aorta and vena cava), the sympathetic plexus (reduces incidence of retrograde ejaculation) and neural structures, that is, preservation of the spinal nerves that cross the posterior aspect of the muscle. The objective of this study is to verify the rates of interbody fusion with the LLIF technique. Methods Retrospective, single center, comparative, non-randomized study. The presence of bone mass with increased hypotransparency in the areas of fusion will be analyzed. For the evaluation of the fusion, the Classification of interbody fusion success: Brantigan, Steffee, Fraser (BSF) will be used. Results Fifty-nine (86%) patients presented complete fusion of the approached level (BSF-3) six months after the procedure. One year after the procedure, 87% of the patients had complete fusion. Similar results were confirmed at two years. Conclusions We conclude that the technique of lateral interbody arthrodesis is safe and effective for the treatment of low back pain, with a fusion rate of 90% in two years. Level of Evidence III. Retrospective study, single center, non-randomized.

Incidence of Pressure-Related Skin Injuries in Patients Operated for Spine Surgery in Prone: A Retrospective Analysis of 307 Patients

Background:

Spine surgery in prone position frequently results in pressure skin lesions (PSLs). No study from Arabic world has published their incidence in literature.

Methods:

We retrospectively analyzed patients who underwent prone position spine surgery from December 1, 2017, to November 30, 2018. They received standardized anesthesia care and were made prone on Jackson table. The face was supported on a nonface contoured foam device, whereas the chest and pelvis were supported on soft cushions. Following completion of surgery, they were turned supine and their skin was inspected for any skin lesions. The lesions were categorized into five grades depending on severity.

Results:

Data of 307 patients were analyzed. Their mean age and weight was 41.5 years and 71 kg, respectively. The mean duration of prone positioning was 470 min. One hundred and three PSLs were observed in 45 patients (14.7%), giving a PSL incidence of 43.7% in affected patients. Majority of patients (18, 40%) with lesions remained in prone position between 421 and 600 min. Multiple lesions were observed in 53.3% of the affected patients. The highest number of patients (21, 46.7%) had one lesion only and it was restricted to face. All lesions were of Grade I, II, or III. Body weight >71 kg was more prone to developing PSLs. Females were more prone to PSLs.

Conclusion:

PSLs in prone position spine surgery occur frequently, and their incidence is proportional to the duration of positioning and weight of the patients. Face is the most commonly affected area.

OPHTHALMOLOGIC COMPLICATIONS IN SPINAL SURGERIES: LITERATURE REVIEW

ABSTRACT Literature review using PubMed, relating ophthalmologic complications in spinal surgery. Ischemic optic neuropathy (ION), central retinal artery occlusion (CRAO) and cortical blindness (CB) constitute the majority of cases. These are rare complications and have a poor prognosis. Post-operative visual loss (POVL) occurs most often in surgical procedures performed in the prone position. Being male, anemia, blood transfusion, and prolonged surgery time are related to ION, while malposition and direct compression of the eyeball are related to the development of CRAO. Level of Evidence III; Systematic reviewbof level III studies.

Prone position surgery for a professional sumo wrestler with thoracic ossification of the posterior longitudinal ligament resulting in intraoperative brachial plexus injury by hypertrophic pectoral muscles

Surgery in the prone position is associated with a variety of complications due to the positioning, including the widely recognized peripheral nerve compression injuries and brachial plexus neuropathy. Previous studies have reported that thin body habitus is a predisposing risk factor for the compressive peripheral nerve injuries due to the prone position surgery. However, prone-position-related brachial plexus injury in patients who are overweight due to hypertrophic muscles have never been reported. Here we report a case of a professional sumo wrestler with severe thoracic ossification of the posterior longitudinal ligament (OPLL). Thoracic OPLL was successfully treated by posterior spinal fusion and decompression surgery. Despite a preoperative simulation and intraoperative inspection of the patient's surgical positioning, he suffered from bilateral upper extremity paralysis immediately after the surgery. Postoperative axillary MRI image revealed a high-intensity area on both sides of his pectoral muscles and axillary fossa, which implied that the pectoral muscles between the ribs and chest pad were pushed out toward the axillary fossa, resulting in compressive brachial plexus injury. His upper extremity motor paralysis was fully recovered in 6 months, but he still has mild tingling sensation even after 12 months of his surgery. In conclusion, overweight patients with hypertrophic muscles pose a risk for brachial plexus entrapment injury by pectoral muscles during prone-position surgery, and therefore it would be more effective to use a wide chest pad to reduce the pressure on the pectoral muscles to prevent it from being pushed out toward the axillary fossa.

Intraoperative angioedema induced by angiotensin II receptor blocker: a case report

Background

Angiotensin II receptor blockers are a class of antihypertensive agent that is developed to exclude the adverse effects of angiotensin converting enzyme inhibitors. However, as angiotensin II receptor blockers have begun to be more widely prescribed, cases of angiotensin II receptor blocker-induced angioedema have been reported. Rare cases of angioedema following surgery in patients using angiotensin converting enzyme inhibitors have been published.

Case presentation

A 38-year-old man with past history of hypertension was admitted for an elective lumbosacral spine surgery. He had been taking Valsartan 160 mg a day for the past 4 years.At the end of the surgical procedure and turning the patient into supine position, we noticed severe swelling in the neck and the face with.an edematous tongue, floor of the mouth, glottis, and supraglottic areas. A diagnosis of drug induced angioedema was made and intravenous dexamethasone, diphenhydramine and ranitidine were given. The patient remained intubated and was transferred to the intensive care unit. The valsartan was suspected to be the precipitating factor for the angioedema and was therefore discontinued.The swelling started to regress after 2 h, and resolved completely by the third day.

Conclusion

The precise mechanism of angiotensin II receptor blocker-induced angioedema is still unknown and should be thoroughly investigated. This report demonstrates a unique case of intraoperative angiotensin II receptor blocker-induced angioedema. Potential differential diagnoses of postoperative facial edema are discussed in detail, including the prolonged prone positioning for posterior spine surgery. Anesthesiologists should be aware of such rare, but potentially dangerous, perioperative adverse reaction that can occur with angiotensin II receptor blockers use.

Incidence and impact of implant subsidence after stand-alone lateral lumbar interbody fusion

BACKGROUND

Few data are available on the occurrence after stand-alone lateral lumbar interbody fusion (LLIF) of implant subsidence, whose definition and incidence vary across studies. The primary objective of this work was to determine the incidence of subsidence 1 year postoperatively, using an original measurement method, whose validity was first assessed. The secondary objective was to assess the clinical impact of subsidence.

HYPOTHESIS

Implant subsidence after stand-alone LLIF is a common complication that can adversely affect clinical outcomes.

MATERIAL AND METHODS

Of 69 included patients who underwent stand-alone LLIF, 67 (97%) were re-evaluated at least 1 year later. Furthermore, 63 (91%) patients had two available computed tomography (CT) scans for assessing subsidence, one performed immediately after surgery and the other 1 year later. Reproducibility of the original measurement method was assessed in a preliminary study. Subsidence was defined as at least 4mm loss of fused space height.

RESULTS

The incidence of subsidence was 32% (20 patients). Subsidence was global in 7 (11%) patients and partial in 13 (21%) patients. Mean loss of height was 5.5±1.5mm. Subsidence predominated anteriorly in 50% of cases. The lordotic curvature of the fused segment was altered in 50% of patients, by a mean of 8°±3°. Fusion was achieved in 67/69 (97%) patients. The Oswestry score and visual analogue scale scores for low-back and nerve-root pain were significantly improved after 1 year in the overall population and in the groups with and without subsidence.

DISCUSSION

Reproducibility of our measurement method was found to be excellent. Subsidence was common but without significant clinical effects after 1 year. Nevertheless, subsidence can be associated with pain and can result in loss of lumbar lordosis, which is a potential risk factor for degenerative disease of the adjacent segments. A score for predicting the risk of subsidence will now be developed by our group as a tool for improving patient selection to stand-alone LLIF.

LEVEL OF EVIDENCE

IV, retrospective cohort study.

Prevalence and Predictors of Pressure Injuries From Spine Surgery in the Prone Position: Do Body Morphological Changes During Deformity Correction Increase the Risks?

MINI: Pressure injuries are prevalent in patients undergoing spine surgery while prone. Multiple risk factors exist and should be addressed. We found that patients undergoing spinal deformity correction surgery are at unique risk (odds ratio 3.31, P = 0.010) due to body morphological changes occurring secondary to intraoperative changes in spinal alignment.

STUDY DESIGN

Review of data and prospective study.

OBJECTIVE

To investigate the prevalence and predictive factors of pressure injuries in spine surgery performed in the prone position, and to determine whether morphological changes and truncal shifts occurring during deformity correction predispose to this complication.

SUMMARY OF BACKGROUND DATA

Spine surgery performed in the prone position presents the risk of developing pressure injuries. This risk is potentially increased in deformity correction, because it tends to involve more extensive procedures, with associated longer operating times.

METHODS

Cases of pressure injuries after spine surgery in the prone position were reviewed to ascertain prevalence and determine risk factors. Data including patient factors (age, sex, height, weight, body mass index, American Society of Anesthesiologists grade, comorbidities, Braden scale, neurological status, spinal pathology) and surgical factors (approach, procedure type, number of screws, operated levels, operative time) were collected. Independent risk factors were identified via multivariate analysis. A subsequent prospective analysis of all patients undergoing spinal deformity correction was conducted by performing intraoperative measurements of body morphological changes and shifts in truncal positions. Statistical correlation was performed to determine whether positional shifts cause pressure injuries.

RESULTS

The prevalence of pressure injuries was 23.0%. Previous skin problems (P = 0.034), myelopathy (P = 0.013), operative time >300 minutes (P = 0.005), and more than four operated levels (P = 0.006) were independent predictors of pressure injuries. Being a spinal deformity patient was also an independent risk factor for developing pressure injuries (odds ratio 3.31, P = 0.010). Significant changes in body measurements during deformity correction were predictive of pressure injuries.

CONCLUSION

Pressure injuries are prevalent in patients undergoing spine surgery while prone. Future studies should investigate strategies to prevent this complication based on the multiple risk factors identified in the present study. Patients undergoing spinal deformity correction surgery are particularly at risk due to intraoperative body morphological changes. Improved padding methods should be trialed in future studies.

LEVEL OF EVIDENCE

3.

Endoscopic Sciatic Nerve Decompression in the Prone Position-An Ischial-Based Approach

Deep gluteal syndrome is described as sciatic nerve entrapment in the region deep to the gluteus maximus muscle. The entrapment can occur from the piriformis muscle, fibrous bands, blood vessels, and hamstrings. Good clinical outcomes have been shown in patients treated by open and endoscopic means. Sciatic nerve decompression with or without piriformis release provides a surgical solution to a difficult diagnostic and therapeutic problem. Previous techniques have used open methods that can now performed endoscopically. The technique of an endoscopic approach to sciatic nerve decompression in the prone position is described as well as its advantages and common findings. Through this ischial-based approach, a familiar anatomy is seen and areas of sciatic nerve entrapment can be readily identified and safely decompressed.

Contemporaneous Evaluation of Intraoperative Ulnar and Median Nerve Somatosensory Evoked Potentials for Patient Positioning: A Review of Four Cases

Somatosensory evoked potentials (SSEPs) are a valuable tool for assessing changes in peripheral nerve pathways caused by patient positioning during spinal surgeries. These changes, when left undiagnosed, may lead to postoperative neurological sequelae. Why an upper extremity SSEP attenuates due to positioning is not necessarily clear and can be multifactorial, affecting the peripheral nerves or elements of the brachial plexus. A conduction block can occur at any point along the course of the nerve secondary to entrapment, compression, and ischemia. These mechanisms of injury may be caused by extreme body habitus, the length of the procedure, or the patient's metabolic underpinnings. The goal of neuromonitoring for positional injury is to predict and prevent both peripheral nerve and brachial plexus injuries. Using ulnar and median nerve SSEPs contemporaneously may lead to better identification of compromised structures when an SSEP change to one or both of the nerves occurs. The investigators provide four case reports where intraoperative SSEP assessment of contemporaneous ulnar and median nerves prevented postoperative upper extremity neural deficits.

Postoperative complications of spine surgery

A variety of surgical approaches are available for the treatment of spine diseases. Complications can arise intraoperatively, in the immediate postoperative period, or in a delayed fashion. These complications may lead to severe or even permanent morbidity if left unrecognized and untreated [1-4]. Here we review a range of complications in the early postoperative period from more benign complications such as postoperative nausea and vomiting (PONV) to more feared complications leading to permanent loss of neurological function or death [5]. Perioperative pain management is covered in a separate review (Chapter 8).