Anaesthesia for spinal surgery in adults

Monitored Anesthesia Care in Minimally Invasive Spine Surgery-A Retrospective Case Series Study

Background and Objectives: Minimally invasive spine surgery (MISS) under monitored anesthesia care (MAC) has emerged as a treatment modality for spinal radiculopathy. It is essential to secure the airway and guarantee spontaneous respiration without endotracheal intubation during MISS in a prone position. Materials and Methods: To evaluate the feasibility and safety of MAC with dexmedetomidine during MISS, we retrospectively reviewed clinical cases. A retrospective review of medical records was conducted between September 2015 and June 2016. A total of 17 patients undergoing MISS were included. Vital signs were analyzed every 15 min. The depth of sedation was assessed using the bispectral index (BIS) and the frequency of rescue sedatives. Adverse events during anesthesia, including bradycardia, hypotension, respiratory depression, postoperative nausea, and vomiting, were evaluated. Results: All cases were completed without the occurrence of airway-related complications. None of the patients needed conversion to general anesthesia. The median maintenance dosage of dexmedetomidine for adequate sedation was 0.40 (IQR 0.40-0.60) mcg/kg/hr with a median loading dose of 0.70 (IQR 0.67-0.82) mcg/kg. The mean BIS during the main procedure was 76.46 ± 10.75. Rescue sedatives were administered in four cases (23.6%) with a mean of 1.5 mg intravenous midazolam. After dexmedetomidine administration, hypotension and bradycardia developed in six (35.3%) and three (17.6%) of the seventeen patients, respectively. Conclusions: MAC using dexmedetomidine is a feasible anesthetic method for MISS in a prone position. Hypotension and bradycardia should be monitored carefully during dexmedetomidine administration.

Optimizing Patient Outcomes in Spinal Surgery: An Investigation Into Anesthesiologists' Case Volume

Introduction Nearly one million patients in the United States undergo spine surgical procedures annually to seek relief from chronic back and neck pain. A multidisciplinary approach is key to ensuring the efficiency and safety of the surgical process, with the anesthesia team, nursing, surgeon, and healthcare facilities all playing a role. The purpose of this study is to capture potential associations between the anesthesiologists' case volume and patient postoperative outcomes in the early recovery period. Methods A retrospective review of anterior cervical discectomy and fusion (ACDF), lumbar decompression (LD), and lumbar fusion (LF) patients from July 2019 to June 2023 was performed. Anesthesiologists were categorized into low, medium, and high volumes of spine surgical cases. Univariate analysis was performed on patient demographics, intraoperative measures, post-anesthesia care unit (PACU) measures, and postoperative measures by anesthesiologist volume. Results This study included 545 ACDF, 815 LD, and 1,144 LF patients. There were no differences between groups in ACDF patients by anesthesiologist volume. When examining patients undergoing LD, there was a difference in patients with an American Society of Anesthesiologists (ASA) physical status classification of three or greater (low volume: 41.7% vs. medium volume: 53.7% vs. high volume: 45.0%; p=0.029). When examining patients undergoing LF, there were differences in patients with low temperatures in PACU (low volume: 2.8% vs. medium volume: 7.3% vs. high volume: 4.2%; p=0.044) and the percentage of patients with a 90-day emergency department return (low volume: 7.7% vs. medium volume: 11.9% vs. high volume: 7.0%; p=0.024). Conclusion While this study found a minimal impact of anesthesiologist volume on postoperative outcomes, recent literature has emphasized the critical role of teamwork and specialized surgical teams to enhance efficiency and patient care. Further studies are warranted to identify other variables in anesthesia, nursing, and surgical team workflow that may impact postoperative outcomes in spinal surgeries.

Predictive factors for respiratory failure and in-hospital mortality after surgery for spinal metastasis

PURPOSE

Spinal metastasis surgeries carry substantial risk of complications. PRF is among complications that significantly increase mortality rate and length of hospital stay. The risk factor of PRF after spinal metastasis surgery has not been investigated. This study aims to identify the predictors of postoperative respiratory failure (PRF) and in-hospital death after spinal metastasis surgery.

METHODS

We retrospectively reviewed consecutive patients with spinal metastasis surgically treated between 2008 and 2018. PRF was defined as mechanical ventilator dependence > 48 h postoperatively (MVD) or unplanned postoperative intubation (UPI). Collected data include demographics, laboratory data, radiographic and operative data, and postoperative complications. Stepwise logistic regression analysis was used to determine predictors independently associated with PRFs and in-hospital death.

RESULTS

This study included 236 patients (average age 57 ± 14 years, 126 males). MVD and UPI occurred in 13 (5.5%) patients and 13 (5.5%) patients, respectively. During admission, 14 (5.9%) patients had died postoperatively. Multivariate logistic regression analysis revealed significant predictors of MVD included intraoperative blood loss > 2000 mL (odds ratio [OR] 12.28, 95% confidence interval [CI] 2.88-52.36), surgery involving cervical spine (OR 9.58, 95% CI 1.94-47.25), and ASA classification ≥ 4 (OR 6.59, 95% CI 1.85-23.42). The predictive factors of UPI included postoperative sepsis (OR 20.48, 95% CI 3.47-120.86), central nervous system (CNS) metastasis (OR 10.21, 95% CI 1.42-73.18), lung metastasis (OR 7.18, 95% CI 1.09-47.4), and postoperative pulmonary complications (OR 6.85, 95% CI 1.44-32.52). The predictive factors of in-hospital death included postoperative sepsis (OR 13.15, 95% CI 2.92-59.26), CNS metastasis (OR 10.55, 95% CI 1.54-72.05), and postoperative pulmonary complications (OR 9.87, 95% CI 2.35-41.45).

CONCLUSION

PRFs and in-hospital death are not uncommon after spinal metastasis surgery. Predictive factors for PRFs included preoperative comorbidities, intraoperative massive blood loss, and postoperative complications. Identification of risk factors may help guide therapeutic decision-making and patient counseling.

The effect of extubation in prone position on emergence and recovery in lumbar spinal surgery

BACKGROUND

Extubation of patients in supine position after prone operations may lead to unwanted effects on hemodynamic and respiratory parameters during emergence and recovery period. We aimed to observe the effects of prone position on emergence and recovery periods after prone surgery.

METHODS

This randomized controlled trial was studied with sixty patients extubated either in prone position (30 patients) or in supine position (30 patients) after lumbar spinal surgery in tertiary educational hospitals. Heart rate, non-invasive arterial blood pressure, peripheral oxygen saturation and Bispectral Index values were measured, and recorded in all patients during operation, at the time an anesthetic agent was discontinued, before and after extubation. The number of the mouth suctioning, Aldrete recovery score, and Ricker agitation score were recorded together with the severity of cough during emergence and recovery. Incidents such as nausea, vomiting, respiratory failure, uncontrolled airway, and decreased saturation were also recorded.

RESULTS

Heart rate and mean arterial pressure values were significantly lower in the prone group during emergence and recovery period compared with the supine group (P<0.05). Aldrete Recovery Scores were higher in the prone group (P<0.001). The number of the mouth suctioning and the cough severity were lower in the prone group (P<0.001).

CONCLUSIONS

Extubation in the prone position provides a more comfortable emergence and recovery periods by less altering the hemodynamic and respiratory status with better recovery profile.

[Anesthesia in spinal surgery]

Over the past 20 years improvements in surgical techniques and perioperative patient care have led to a considerable increase in surgical procedures of the spine worldwide. Therefore, the spectrum was extended from minimally invasive procedures up to complex operations over several segments of the spinal column with high loss of blood and complex perioperative management. This article presents the principal pillars of preoperative, intraoperative and postoperative management relating to spinal surgery. Furthermore, procedure-specific features, such as airway management in cervical spine instability or implementation of intraoperative neuromonitoring are dealt with in detail.

A Double-Blind, Randomized Controlled Pilot Trial to Assess the Analgesic Efficacy of Ultrasound-Guided Preemptive Caudal Morphine as an Adjunct to Bupivacaine for Lumbosacral Spine Surgeries in Adults

Background

The analgesic efficacy of preemptive administration of caudal morphine for spine surgeries in adults is not well studied. In a double-blinded, randomized controlled trial, safety and analgesic efficacy of preemptive, single-shot caudal morphine and bupivacaine was compared with caudal bupivacaine alone in lumbosacral spine surgeries.

Methods

After Institutional Ethics Committee approval, 40 patients aged 18-60 yrs planned for lumbosacral spine surgery were randomized to groups of 20 patients each. After induction and prone positioning, an ultrasound-guided caudal block was performed with morphine 50 µg/kg with 20 ml 0.25% bupivacaine in the study group (LM) and only bupivacaine in the control group (LA). Postoperatively, both groups received intravenous morphine via patient-controlled analgesia (PCA) pump (No basal, 1 mg/bolus, 10 minutes lockout interval). Intraoperative fentanyl use, postoperative 24-h morphine consumption, visual analogue pain scores (VAS) and adverse effects of morphine were noted.

Results

Demographics and baseline data were comparable. Postoperative 24-hour morphine requirement was more in LA group (34.3 ± 10.7 mg vs 19.65 ± 11.8 mg, p=0.0001). Total intraoperative supplemental fentanyl requirement was similar (79.25 ± 67.60 µg in LA vs 54 ± 50.20 µg in LM group, p=0.28). VAS scores at 2/4/6/12-hour in group-LM were significantly less than group-LA (p=0.005, 0.002, 0.001 and 0.047) but were comparable at 18 and 24 hours (p=0.25, 0.42). Postoperative incidence of adverse effects of morphine was comparable.

Conclusions

Ultrasound-guided, single-shot preemptive administration of caudal morphine with bupivacaine is a safe and effective modality of analgesia for patients undergoing lumbosacral spine surgeries.

Hemostats in Spine Surgery: Literature Review and Expert Panel Recommendations

Bleeding in spine surgery is a common occurrence but when bleeding is uncontrolled the consequences can be severe due to the potential for spinal cord compression and damage to the central nervous system. There are many factors that influence bleeding during spine surgery including patient factors and those related to the type of surgery and the surgical approach to bleeding. There are a range of methods that can be employed to both reduce the risk of bleeding and achieve hemostasis, one of which is the adjunct use of hemostatic agents. Hemostatic agents are available in a variety of forms and materials and with considerable variation in cost, but specific evidence to support their use in spine surgery is sparse. A literature review was conducted to identify the pre-, peri-, and postsurgical considerations around bleeding in spine surgery. The review generated a set of recommendations that were discussed and ratified by a wider expert group of spine surgeons. The results are intended to provide a practical guide to the selection of hemostats for specific bleeding situations that may be encountered in spine surgery.

The Prognostic Value of Intraoperative Neuromonitoring by Combining Somatosensory- and Motor-Evoked Potentials for Thoracic Spinal Decompression Surgery in Patients with Neurological Deficit

STUDY DESIGN

Retrospective study.

OBJECTIVE

To explore a relation between somatosensory- and motor-evoked potential (SEPs, MEPs) and corresponding thoracic cord function for thoracic spinal decompression surgery (TSDS) in patients with neurological deficit.

SUMMARY OF BACKGROUND DATA

Although SEPs and MEPs monitoring has been developed as an essential technique in spinal surgery. There are limited data on the reliability of using SEPs and MEPs for TSDS and its prognosis.

METHODS

One hundred twenty patients underwent TSDS in our hospital, 91 patients completed the trial. All the patients were divided into three subgroups according to the changes of MEPs and SEPs: neither SEPs nor MEP deteriorated -. Simply MEP deteriorated and both SEPs and MEP deteriorated -. Bispectral (BIS) was used to monitor the depth of sedation, which ranged from 40 to 60 by varying the infusion speed of anesthetics. The pre- and postoperative spinal function was assessed by muscle strength and Japanese Orthopaedic Association (JOA) score at three time points:1) before surgery; 2) immediately after general anesthesia recovery; 3) after 3-month follow-up.

RESULTS

Sixty-nine cases showed neither SEPs nor MEP deteriorated -, 10 cases showed only MEP deteriorated, and 12 cases showed both SEPs and MEP deteriorated -. The patients in the group where neither SEPs nor MEP deteriorated had the best recovery of the extremity muscle strength, the shortest recovery time (8.10 ± 1.60, P < 0.05), and toe movement time (8.50 ± 1.60, P < 0.05). There is a strong correlation between SEPs variability ratio at T4 time point and JOA recovery ratio (JOA RR) in the 3-month follow-up.

CONCLUSION

Combined SEPs and MEPs monitoring are important for TSDS in patients with neurological deficit and it is helpful for evaluating postoperative prognosis. It is more accurate to record SEPs at T4 time point to predict the patients' prognosis.Level of Evidence: 3.

Resistance to Neuromuscular Blockade by Rocuronium in Surgical Patients with Spastic Cerebral Palsy

Individuals with spastic cerebral palsy (CP) often exhibit altered sensitivities to neuromuscular blocking agents (NMBAs) used for surgical intubation. We assessed usage of the NMBA rocuronium in patients with spastic CP and evaluated potential modifiers of dosing including gross motor function classification system (GMFCS) level, birthweight, gestational age, and the use of anticonvulsant therapy. In a case-control study, surgical patients with spastic CP (n = 64) or with idiopathic or non-neuromuscular conditions (n = 73) were enrolled after informed consent/assent. Patient data, GMFCS level, anticonvulsant use, and rocuronium dosing for intubation and post-intubation neuromuscular blockade were obtained from medical records. Findings reveal participants with CP required more rocuronium per body weight for intubation than controls (1.00 ± 0.08 versus 0.64 ± 0.03 mg/kg; p < 0.0001). Dosing increased with GMFCS level (Spearman's rho = 0.323; p = 0.005), and participants with moderate to severe disability (GMFCS III-V) had elevated rocuronium with (1.21 ± 0.13 mg/kg) or without (0.86 ± 0.09 mg/kg) concurrent anticonvulsant therapy. Children born full-term or with birthweight >2.5 kg in the CP cohort required more rocuronium than preterm and low birthweight counterparts. Individuals with CP exhibited highly varied and significant resistance to neuromuscular blockade with rocuronium that was related to GMFCS and gestational age and weight at birth.

Effects of ventilation mode type on intra-abdominal pressure and intra-operative blood loss in patients undergoing lumbar spine surgery: A randomised clinical study

Background and Aims:

The aim of the study was to evaluate the effect of mode of mechanical ventilation; pressure-controlled ventilation (PCV) vs. volume-controlled ventilation (VCV) on airway pressures, intra-abdominal pressure (IAP) and intra-operative surgical bleeding in patients undergoing lumbar spine surgery.

Methods:

This was a prospective, randomised study that included 50 American Society of Anesthesiologists class I and II patients undergoing lumbar spine surgery who were mechanically ventilated using PCV or VCV mode. The respiratory parameters (peak and plateau pressures) and IAP were measured after anaesthesia induction in supine position, 10 min after the patients were changed from supine to prone position, at the end of the surgery in prone position, and after the patients were changed from prone to supine position. The amount of intraoperative surgical bleeding was measured by objective and subjective methods.

Results:

The primary outcome was the amount of intraoperative surgical bleeding. It was significantly less in the PCV group than in the VCV group (137 ± 24.37 mL vs. 311 ± 66.98 mL) (P = 0.000). Similarly, on comparing other parameters like peak inspiratory pressures, plateaupressures and IAP, the patients in PCV group had significantly lower parameters than those in VCV group (P < 0.05). No harmful events were recorded.

Conclusion:

In patie,nts undergoing lumbar spine surgery, use of PCV mode decreased intraoperative surgical bleeding, which may be related to lower intraoperative respiratory pressures and IAP.

Effect of prone position without volume expansion on pulse pressure variation in spinal surgery : a prospective observational study

Background : Pulse pressure variation (PPV) is a predictor of fluid responsiveness in supine patients under mechanical ventilation. Its use has also been validated in the prone position. The aim of this study was to assess changes in PPV induced by prone position in patients undergoing spinal surgery. Methods : Ninety-six patients aged 12 to 75 years, scheduled for elective spinal surgery were included. Patients were excluded if they had clinical signs related to any organ failure, or if they required vasoactive drugs and/or volume expansion during the early stages of anesthesia. Patients received a standardized anesthesia protocol. Fluid expansion was not allowed from induction until 10 minutes after positioning. Hemodynamic measurements recorded before the induction of anesthesia (T0) included : arterial pressure (systolic (SAP) diastolic (DAP) and mean (MAP)) and heart rate (HR). Radial artery was cannulated after intubation and measurements, as well as PPV, were noted in supine position (T1). Patients were then placed in prone position hemodynamics and PPV measurements were repeated (T2). Results : Forty-eight patients completed the study. Anesthesia induction induced a significant decrease in SAP, DAP, and MAP with no effect on HR. Prone position did not induce any significant changes in SAP, MAP, DAP, and HR. A significant difference was found between PPV values in supine (Mean=10.5, SD=4.5) and prone positions (Mean=15.2, SD=7.1) ; t=-4.15 (p<0.001). The mean increase in PPV was 4.7%. Conclusion : Prone position without prior volume expansion induces a significant increase in PPV prior to any modification in arterial blood pressure and heart rate.

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.

Is it mandatory to routinely use image intensifier during scoliosis surgery? – Results of an email survey

Background

Methods

Results

Conclusions

The effect of dexmedetomidine on motor-evoked potentials during pediatric posterior spinal fusion surgery: a retrospective case-control study

PURPOSE

Motor-evoked potentials (MEPs) are frequently used in pediatric posterior spinal fusion surgery (PSFS) to detect spinal cord ischemia. Dexmedetomidine is increasingly being used as an adjunct to total intravenous anesthesia, but its effect on MEP amplitude has been variably reported. The purpose of this study was to evaluate the effect of an infusion of dexmedetomidine on the amplitude of MEPs.

METHODS

We performed a retrospective case-control study of 30 pediatric patients who received a 0.5 µg·kg^-1·hr^-1 infusion of dexmedetomidine, ten patients who received 0.3 µg·kg^-1·hr^-1 dexmedetomidine, and 30 control patients who did not receive dexmedetomidine during PSFS. Two neurophysiologists reviewed the MEP amplitudes in six muscle groups at three time points: when the patient was turned prone (baseline; T1), one hour after incision (T2), and after exposure of the spine but before insertion of the first screw (T3).

RESULTS

In all muscles tested, the mean MEP amplitude was reduced by T3 when dexmedetomidine was infused at 0.5 µg·kg^-1·hr^-1. The greatest reduction from baseline MEP amplitude was 829 µV (95% confidence interval, 352 to 1230; P < 0.001) seen in first right dorsus interosseous. When dexmedetomidine was infused at 0.3 µg·kg^-1·hr^-1, there was a significant reduction in MEP amplitude in four of the six muscles tested at T3 compared with the control group.

CONCLUSIONS

Dexmedetomidine at commonly used infusion rates of 0.3 µg·kg^-1·hr^-1 or 0.5 µg·kg^-1·hr^-1 causes a significant decrease in MEP amplitude during pediatric PSFS. We suggest that dexmedetomidine should be avoided in children undergoing PSFS so as not to confuse the interpretation of this important neurophysiological monitor.

Consensus document for multimodal intraoperatory neurophisiological monitoring in neurosurgical procedures. Basic fundamentals

The present work aims to establish a guide to action, agreed by anaesthesiologists and neurophysiologists alike, to perform effective intraoperative neurophysiological monitoring for procedures presenting a risk of functional neurological injury, and neurosurgical procedures. The first section discusses the main techniques currently used for intraoperative neurophysiological monitoring. The second exposes the anaesthetic and non-anaesthetic factors that are likely to affect the electrical records of the nervous system structures. This section is followed by an analysis detailing the adverse effects associated with the most common techniques and their use. Finally, the last section describes a series of guidelines to be followed upon the various intraoperative clinical events.

Long-Term Opioid Prescriptions After Spine Surgery: A Meta-Analysis of Prevalence and Risk Factors

BACKGROUND

Opioids are frequently prescribed for back pain, but the prevalence of and risk factors for long-term opioid use after spine surgery were not clearly reported. We conducted a systematic review and meta-analysis to summarize the evidence for long-term opioid use (>90 days) among adults who underwent spine surgery.

METHODS

PubMed, EMBASE, and Cochrane indexing databases were searched until November 9, 2018 for studies reporting the prevalence of and risk factors for long-term opioid use after spine surgery. Separate meta-analyses were conducted for commercial claims databases or registries (claims/registries) and nonclaims observational studies using the random-effects model to estimate the pooled odds ratio (OR). Prevalence meta-analysis was performed in a clinically homogeneous subset of these patients who underwent lumbar spine surgery.

RESULTS

Eight claims and 5 nonclaims were meta-analyzed to avoid double-counting participants. The meta-analysis showed that preoperative opioid users (OR, 5.59; 95% confidence interval [CI], 3.37-9.27 vs. OR 4.21; 95% CI, 2.72-6.51) and participants with preexisting depression and/or anxiety (OR, 1.86, 95% CI, 1.43-2.42 and OR, 1.20; 95% CI, 0.83-1.74, respectively) had a statistically significantly higher odds of long-term postoperative opioids, compared with their peers. Males showed lower odds of long-term postoperative opioid use in the claims group (OR, 0.85; 95% CI, 0.79-0.92), but not in the nonclaims group (OR, 0.99; 95% CI, 0.71-1.39). The pooled prevalence of post-lumbar spine surgery long-term opioid use was 63% (95% CI, 50%-74%) in claims and 47% (95% CI, 38%-56%) in nonclaims.

CONCLUSIONS

Patients undergoing spine surgery represent a high-risk surgical population requiring special attention and targeted interventions, with the strongest evidence for those treated with opioids before surgery and those with psychiatric comorbidities.

Reducing Allogenic Blood Transfusion in Pediatric Scoliosis Surgery:: Reporting 15 Years of a Multidisciplinary, Evidence-Based Quality Improvement Project

STUDY DESIGN

Retrospective review of prospectively collected spinal surgery and transfusion databases.

OBJECTIVES

To evaluate the efficacy of a care pathway developed at our institution since 2003 with a focus on reducing the need for blood transfusions in children undergoing scoliosis correction surgery. The care pathway includes nurse-led clinics facilitating preoperative hemoglobin optimization, intraoperative cell salvage, the use of tranexamic acid, and a transfusion criteria awareness program.

METHODS

Retrospective review of our institution's prospectively recorded spinal surgery and transfusion databases including all cases of scoliosis surgery in patients 18 years and younger between 2001 and 2015.

RESULTS

A total of 1039 procedures were included in the analysis. Overall, 24.4% of patients received a transfusion. The proportion of patients transfused was 89.2% in 2001-2003, 39.6% in 2004-2006, 16.5% in 2007-2009, 15.6% in 2010-2012, and 20.1% in 2013-2015. The volume of blood products transfused in those undergoing transfusion was 9.1 units in 2001-2003, 4.8 units in 2004-2006, 5.0 units in 2007-2009, 2.3 units in 2010-2012, and 2.1 units in 2013-2015. A multivariate logistic regression demonstrated adjusted odds ratios for the probability of receiving any transfusion of 5.45 (95% confidence interval 3.62-8.11) for patients with neuromuscular diagnoses and 11.17 (5.02-24.86) for those undergoing combined anterior and posterior surgical approach.

CONCLUSIONS

We have demonstrated over a 15-year period that the introduction of a multifaceted, multidisciplinary pathway can dramatically and sustainably reduce the need for blood transfusions and their attendant risks in pediatric scoliosis surgery. This data lends weight to the adoption of such a care pathway in pediatric scoliosis surgery.

Comparison between effect of desflurane/remifentanil and propofol/remifentanil anesthesia on somatosensory evoked potential monitoring during scoliosis surgery-A randomized controlled trial

BACKGROUND

Drugs used in anesthesia can affect somatosensory evoked potential (SSEP) monitoring, which is used routinely for intraoperative monitoring of spinal cord integrity during spinal surgery.

OBJECTIVE

The objective of this study was to determine whether combined total intravenous anesthesia (TIVA) technique with propofol/remifentanil is associated with less SSEP suppression when compared to combined volatile agent desflurane/remifentanil anesthesia during corrective scoliosis surgery at a comparable depth of anesthesia.

DESIGN

It is a randomized controlled trial.

SETTING

The study was conducted at the Single tertiary University Hospital during October 2014 to June 2015.

PATIENTS

Patients who required SSEP and had no neurological deficits, and were of American Society of Anesthesiologist I and II physical status, were included. Patients who had sensory or motor deficits preoperatively and significant cardiovascular and respiratory disease were excluded. A total of 72 patients were screened, and 67 patients were randomized and allocated to two groups: 34 in desflurane/remifentanil group and 33 in TIVA group. Four patients from desflurane/remifentanil group and three from TIVA group were withdrawn due to decrease in SSEP amplitude to <0.3 µV after induction of anesthesia. Thirty patients from each group were analyzed.

INTERVENTIONS

Sixty-seven patients were randomized to receive TIVA or desflurane/remifentanil anesthesia.

MAIN OUTCOME MEASURES

The measurements taken were the amplitude and latency of SSEP monitoring at five different time points during surgery: before and after the induction of anesthesia, at skin incision, at pedicle screw insertion, and at rod insertion.

RESULTS

Both anesthesia techniques, TIVA and desflurane/remifentanil, resulted in decreased amplitude and increased latencies of both cervical and cortical peaks. The desflurane/remifentanil group had a significantly greater reduction in the amplitude ( p = 0.004) and an increase in latency ( p = 0.002) of P40 compared with the TIVA group. However, there were no differences in both amplitude ( p = 0.214) and latency ( p = 0.16) in cervical SSEP between the two groups.

CONCLUSIONS

Compared with TIVA technique, desflurane/remifentanil anesthesia caused more suppression in cortical SSEP, but not in cervical SSEP, at a comparable depth of anesthesia.

Multimodal Analgesia for Perioperative Management of Patients presenting for Spinal Surgery

Multimodal, non-opioid based analgesia has become the cornerstone of ERAS protocols for effective analgesia after spinal surgery. Opioid side effects, dependence and legislation restricting long term opioid use has led to a resurgence in interest in opioid sparing techniques. The increasing array of multimodal opioid sparing analgesics available for spinal surgery targeting novel receptors, transmitters, and altering epigenetics can help provide an optimal perioperative experience with less opioid side effects and long-term dependence. Epigenetic mechanisms of pain may enhance or suppress gene expression, without altering the genome itself. Such mechanisms are complex, dynamic and responsive to environment. Alterations that occur can affect the pathophysiology of pain management at a DNA level, modifying perceived pain relief. In this review, we provide a brief overview of epigenetics of pain, systemic local anesthetics and neuraxial techniques that continue to remain useful for spinal surgery, neuropathic agents, as well as other common and less common target receptors for a truly multimodal approach to perioperative pain management.

Lumbar Spine Surgeries Under Spinal Anesthesia in High-Risk Patients: A Retrospective Analysis

OBJECTIVE

To determine outcomes of spinal anesthesia (SA) in high-risk patients undergoing lumbar spine surgery in whom general anesthesia (GA) was contraindicated.

METHODS

A retrospective study was conducted in Bansal Hospital, Bhopal, India. SA was achieved with a heavy spinal dose of bupivacaine administered in the sitting position. After assessing sensory level, patients were placed into prone position. Throughout surgery, hemodynamic parameters were monitored. At the end of surgery, patients were placed into supine position and taken out of the operating room for monitoring in the recovery room. Postoperatively, time spent in the postanesthesia care unit, hemodynamic changes, incidence of nausea and vomiting, urinary retention, spinal headache, analgesic use, regression of sensory block, and length of hospital stay were documented. Patient and surgeon satisfaction was also assessed.

RESULTS

The study included 18 high-risk patients with lumbar spine disease. Twelve patients were classified as American Society of Anesthesiologists IV, and 6 were classified as American Society of Anesthesiologists III. Ten patients underwent microdiscectomy, and 8 patients underwent canal and lateral recess decompression. None of the patients had anesthetic or surgical complications. Postoperative pain relief was excellent. There were no incidences of postoperative vomiting or urinary retention. Only 2 patients (11.11%) developed nausea. Both surgeons and patients reported a high level of satisfaction. SA was 12% cheaper than general anesthesia.

CONCLUSIONS

SA is a safe, reliable, and satisfactory alternative to general anesthesia in high-risk lumbar spine surgeries. Postoperative morbidity and mortality can be reduced by SA and spinal analgesia techniques. SA allows good perioperative hemodynamic stability. It is also more cost-effective.

Efficacy of local wound infiltration analgesia with ropivacaine and dexmedetomidine in tubercular spine surgery - A pilot randomised double-blind controlled trial

Background and Aims:

Regional analgesic techniques are difficult to use in tubercular spine patients due to distorted spinal anatomy and presence of infection. This study was conducted with the aim to evaluate analgesic efficacy of local wound infiltration before wound closure in tubercular spine patients.

Methods:

This pilot randomised double-blind controlled study was conducted in 32 American Society of Anesthesiologists I-III patients, age ≥15 years, undergoing elective surgery for spinal tuberculosis. All the patients received general anaesthesia using standard technique and intravenous morphine for intraoperative analgesia. They received wound infiltration with either normal saline (group C) or local infiltration analgesia with 0.375% ropivacaine 3 mg/kg, adrenaline 5 μg/mL and dexmedetomidine 1 μg/kg in a total volume of 0.8 mL/kg (group LIA) before wound closure. Patient-controlled analgesia using intravenous morphine provided postoperative analgesia. The primary objective was to study 24-h morphine consumption, whereas the secondary objectives included pain scores, complications and patient satisfaction. Repeated measures analysis of variance, Chi-square test and Mann–Whitney U test were used for statistical analysis.

Results:

Morphine requirement was lower in group LIA (6.7 ± 2.7 mg) than in group C (27.7 ± 7.9 mg);P < 0.001. Group LIA also had lower pain scores (P < 0.001), longer time to rescue analgesic (P < 0.001), better patient satisfaction to pain relief (P = 0.001) and lower incidence of postoperative nausea and vomiting than group C.

Conclusion:

Wound infiltration with ropivacaine, adrenaline and dexmedetomidine before wound closure provided good postoperative analgesia with lower morphine requirement.

Postoperative Complications Associated With rhBMP2 Use in Posterior/Posterolateral Lumbar Fusion

STUDY DESIGN

Retrospective database review.

OBJECTIVE

Posterior/posterolateral lumbar fusion (PLF) is an effective treatment for a variety of spinal disorders; however, variations in surgical technique have different complication profiles. The aim of our study was to quantify the frequency of various complications in patients undergoing PLF with and without human recombinant bone morphogenetic protein 2 (rhBMP2).

METHODS

We queried the orthopedic subset of the Medicare database (PearlDiver) between 2005 and 2011 for patients undergoing PLF procedures with and without rhBMP2. Complication and reoperation rates were analyzed within 1 year of the index procedure. Complications assessed include: acute renal failure, deep vein thrombosis, dural tear, hematoma, heterotopic ossification, incision and drainage, cardiac complications, nervous system complications, osteolysis, pneumonia, pseudarthrosis, pulmonary embolism, radiculopathy, respiratory complications, sepsis, urinary retention, urinary tract infection, mechanical, and wound complications. Chi-square analysis was used to calculate the complication differences between the groups.

RESULTS

Our data revealed higher overall complication rates in patients undergoing PLF with rhBMP2 versus no_rhBMP2 (76.9% vs 68.8%, P < .05). Stratified by gender, rhBMP2 males had higher rates of mechanical complications, pseudarthrosis, and reoperations compared with no_rhBMP2 males (P < .05), whereas rhBMP2 females had higher rates of pseudarthrosis, urinary tract infection, and urinary retention compared with no_rhBMP2 females (P < .05).

CONCLUSION

Our data revealed higher overall complication rates in PLF patients given rhBMP2 compared with no_rhBMP2. Furthermore, our data suggests that rhBMP2-associated complications may be gender specific.

A prospective randomized study comparing recovery following anesthesia with a combination of intravenous dexmedetomidine and desflurane or sevoflurane in spinal surgeries

Background and Aims:

Desflurane and sevoflurane are inhalational anesthetics which provide stable intraoperative hemodynamics and rapid emergence from anesthesia. Dexmedetomidine is an α2-agonist with sedative and hypnotic effects. We compared recovery following anesthesia with a combination of a continuous intravenous infusion of dexmedetomidine and desflurane or sevoflurane in cases of spine surgeries because no such data are available from India.

Material and Methods:

It was a single-blind, prospective, randomized study. After institutional ethics committee approval, patients were randomly allocated to one of the two groups of fifty patients each. Group D received desflurane and Group S received sevoflurane, along with dexmedetomidine 0.5 μg/kg/h IV infusion for maintenance of anesthesia.

Results and Conclusions:

Extubation time (ET) in Group D was shorter by 4.2 min than in Group S (10.1 ± 2.2 and 14.2 ± 1.3; P = 0.004). Postoperative recovery, postoperative analgesic, and antiemetic requirement between the groups were comparable The mean dial setting required to maintain the minimum alveolar concentration of 1 intraoperatively was 3.1 for desflurane and 0.7 for sevoflurane.

Comparison of bispectral index and end-tidal anaesthetic concentration monitoring on recovery profile of desflurane in patients undergoing lumbar spine surgery

Background and Aims:

Several techniques have evolved over time to monitor depth of anesthesia and ensure enhanced recovery. This randomized double-blinded trial was designed to compare bispectral index (BIS) or end-tidal anaesthetic concentration (ETAC) monitoring on the recovery characteristics of patients undergoing thoracolumbar spine surgeries.

Methods:

Seventy American Society of Anesthesiologist I–II patients of either sex were randomized to Group B – BIS-guided protocol, Group E – ETAC-guided protocol, or Group S – Standard protocol. After intravenous induction, anaesthesia was maintained with desflurane in O₂/N₂O (50:50) mixture. In BIS, ETAC and Standard groups, inspired end-tidal desflurane concentration was varied to achieve BIS of 45–55, 0.8–1.0 age-corrected minimum alveolar concentration, and haemodynamic parameters within 20% of the baseline, respectively. Time to eye opening (emergence time, the primary outcome), time to extubation, and time to name recall from the discontinuation of the anaesthetic agent were recorded. Incidence of nausea, vomiting, and total analgesic consumption was noted for 24 h.

Results:

Emergence time (mean ± SD) in ETAC (5.1 ± 1.53 min) and BIS (5.0 ± 2.12 min)-guided groups was significantly lower than Standard group (7.5 ± 2.90 min). Extubation time in ETAC (6.3 ± 2.22 min) and BIS-guided group (6.5 ± 1.78 min) was significantly lower than Standard group (9.0 ± 3.20 min) (P < 0.001). Time to achieve fast track score of more than 12 was significantly less in BIS-guided group (13.12 ± 2.59 min).

Conclusion:

ETAC-guided anaesthesia is comparable to BIS-guided anaesthesia in achieving early recovery.

Predictors of Long-term Opioid Use Following Lumbar Fusion Surgery

STUDY DESIGN

A population-based retrospective cohort study.

OBJECTIVE

The aim of this study was to examine risk factors for long-term opioid use following lumbar spinal fusion surgery in a nationally representative cohort of commercially insured adults.

SUMMARY OF BACKGROUND DATA

Opioid prescription rates for the management of low back pain have more than doubled in the US over the past decade. Although opioids are commonly used for the management of pain following lumbar spinal fusion surgery, to date, no large-scale nationally representative studies have examined the risk factors for long-term opioid use following such surgical intervention.

METHODS

Using one of the nation's largest commercial insurance databases, we conducted a retrospective cohort study of 8377 adults, aged 21 to 63 years, who underwent lumbar spinal fusion surgery between January 1, 2009, and December 31, 2012. Long-term opioid use was defined as ≥365 days of filled opioid prescriptions in the 24 months following lumbar fusion. Multivariable logistic regression was used to calculate adjusted odds ratios (ORs) and 95% confidence intervals for the risk of long-term opioid use following lumbar fusion.

RESULTS

After adjusting for covariates, the following factors were associated with an increased risk of long-term opioid use following surgery: duration of opioid use in the year before lumbar surgery [Referent (0 days); Quartile 1 (1-22 days) OR = 2.27, 95% CI = 1.48-3.49; Quartile 2 (23-72 days): OR = 5.94, 95% CI = 4.00-8.83; Quartile 3: (73-250 days) OR = 25.31, 95% CI = 17.26-37.10; Quartile 4 (≥250 days) OR = 219.95, 95% CI = 148.53-325.71)], refusion surgery (OR = 1.32, 95% CI = 1.02-1.72), and diagnosis of depression (OR = 1.43, 95% CI = 1.18-1.74). Receipt of anterior fusion was associated with a modest decrease in the risk of long-term opioid use (OR = 0.79, 95% CI = 0.63-0.99).

CONCLUSION

These findings may provide clinically relevant information to physicians, patients, and their families regarding the risk factors for opioid dependence following lumbar fusion surgery.

LEVEL OF EVIDENCE

3.

Cervical Spine Surgery Complications and Risks in the Elderly

STUDY DESIGN

Cervical decompression (CD) and cervical fusion (CF) patients in 5% Medicare Part B claims data.

OBJECTIVE

Evaluate the complication rate and associated risk factors after cervical spine surgery using a national sample of elderly patients.

SUMMARY OF BACKGROUND DATA

The number of cervical spine procedures in the United States has risen along with associated hospital costs. Postoperative complications lead to longer hospitalizations and greater costs.

METHODS

Demographic information and postoperative complications (90 days) were evaluated. Multivariate Cox regression was used to evaluate the risk factors for the complications, while adjusting for age, socioeconomic status, Charlson comorbidity index, race, census region, sex, and year of surgery.

RESULTS

Between 2010 and 2012, 1519 CD and 1273 CF Medicare patients were identified in the dataset. Respiratory complications (CD: 12.1% and CF: 14.6%), urinary retention (CD: 8.2% and CF: 9.1%), acute delirium (CD: 5.3% and CF: 6.0%), and nausea/vomiting (CD: 2.8% and CF: 3.1%) were the most commonly diagnosed complications. All other complications had an incidence of less than 1.5%. Older patients had higher risks of respiratory complications for both procedures, and CD patients with Charlson scores of 1 to 2 and 5+ were also at higher risk of respiratory complications. Males (P <0.001) were at higher risk of urinary retention. Patients with dementia (P <0.001) had a higher risk of acute delirium after both CD and CF. For CD patients, those aged 85 years and over had higher risk of acute delirium, along with patients with transient ischemic attack/stroke. Age was also a significant risk factor (P = 0.019) for acute delirium for CF patients. Females were at a significantly higher risk of nausea/vomiting after CD and CF.

CONCLUSION

These data help to provide baseline information regarding the complication rates in the elderly CD and CF patient population in the United States, and will serve to help minimize these complications.

LEVEL OF EVIDENCE

3.

A comparative study of Sterofundin and Ringer lactate based infusion protocol in scoliosis correction surgery

Background:

A major change in anesthesia practice as regards to intraoperative infusion therapy is the present requirement. Switching over to balanced fluids can substantially decrease the incidence of lactic acidosis and hyperchloremic acidosis. The deleterious effects of unbalanced fluids are more recognizable during major surgeries. We prospectively studied the influence of Sterofundin (SF) and Ringer lactate (RL) on acid–base changes, hemodynamics, and readiness for extubation during scoliosis surgery.

Subjects and Methods:

Thirty consecutive children posted for scoliosis surgery were randomized to receive either RL (n = 15) or SF (n = 15) as intraoperative fluid at 10 mg/kg/h. Fluid boluses were added according to the study fluid algorithm. Arterial blood was sampled and analyzed at hourly intervals during surgery. Red blood cell transfusion was guided by hematocrit below 27. Patients were followed for 24 h postoperatively in the Intensive Care Unit.

Results:

There was no statistically significant difference in the volume of infused fluid (2400 ± 512 ml in Group RL and 2200 ± 640 ml in Group SF. There were no significant changes in pH of patients infused with SF. Statistically, significant higher lactate levels were seen in RL-infused group. The strong ion difference was decreased in both groups, but it normalized earlier with SF.

Conclusions:

SF-infused patients had nonremarkable changes in acid–base physiology in scoliosis surgery.

Presentation of neurogenic shock within the emergency department

BACKGROUND

Injury to the spinal cord can result in loss of sympathetic innervation causing a drop in BP and HR, this condition is known as neurogenic shock. There is debate among the literature on how and when neurogenic shock presents and what values of HR and BP should be used to define it. Previous studies do not take into account multiple prehospital and emergency department recordings.

OBJECTIVE

To improve understanding of how neurogenic shock presents in humans, allowing better identification and treatment.

METHODS

The Trauma Audit and Research Network database for an adult major trauma centre was used to isolate patients with a spinal cord injury. Qualifying patients had all available BPs and HRs collated into a database. Patients with neurogenic shock were isolated, allowing data analysis.

RESULTS

Out of 3069 trauma patients, 33 met the inclusion criteria, of which 15 experienced neurogenic shock. 87% of the patients who had neurogenic shock experienced it within 2 hours of injury. Neurogenic shock below the T6 level was less common (p=0.009); however, there were still four cases in the cohort. More patients with complete spinal cord injury had neurogenic shock (p=0.039).

CONCLUSIONS

Neurogenic shock is variable and unpredictable. It can present in the prehospital environment and without warning in a patient with previously normal vital signs. The medical team should be aware of it in all patients with spinal cord injury regardless of injury level.

Emergency Neurological Life Support: Traumatic Spine Injury

Traumatic spine injuries (TSIs) carry significantly high risks of morbidity, mortality, and exorbitant health care costs from associated medical needs following injury. For these reasons, TSI was chosen as an ENLS protocol. This article offers a comprehensive review on the management of spinal column injuries using the best available evidence. Alhough the review focuses primarily on cervical spinal column injuries, thoracolumbar injuries are briefly discussed as well. The initial emergency department clinical evaluation of possible spinal fractures and cord injuries, along with the definitive early management of confirmed injuries, is also covered.

Postoperative respiratory failure necessitating transfer to the intensive care unit in orthopedic surgery patients: risk factors, costs, and outcomes

Background

Postoperative pulmonary complications in orthopedic surgery patients have been associated with worse clinical outcomes. Identifying patients with respiratory risk factors requiring enhanced monitoring and management modifications is an important part of postoperative care. Patients with unanticipated respiratory decompensation requiring transfer to the intensive care unit (ICU) have not been studied in sufficient detail.

Methods

A retrospective case-control study of elective orthopedic surgery patients (knee, hip, shoulder, or spine, n = 51) who developed unanticipated respiratory failure (RF) necessitating transfer to the ICU over a 3-year period was conducted. Controls (n = 153) were frequency matched to cases by gender, age, and surgical procedure. Patient and perioperative care factors, clinical outcomes, and cost of care were examined.

Results

Transfer to the ICU occurred within 48 h of surgery in 73 % of the cases, 31 % required non-invasive ventilation, and 18 % required mechanical ventilation. Cases had a higher prevalence of chronic obstructive pulmonary disease (COPD), obstructive sleep apnea (OSA), and regular psychotropic medication use than controls. Cases received more intravenous opioids during the first 24 postoperative hours, were hospitalized 4 days longer, had higher in-hospital mortality, and had excess hospitalization costs of US$26,571. COPD, OSA, preoperative psychotropic medications, and anesthesia time were associated with risk of RF in a multivariate analysis.

Conclusions

Unanticipated RF after orthopedic surgery is associated with extended hospitalization, increased mortality, and higher cost of care. Hospital protocols that include risk factor assessment, enhanced monitoring, and a cautious approach to opioid use in high-risk patients may reduce the frequency of this complication.

Comparative Efficacy of the Air-Q Intubating Laryngeal Airway during General Anesthesia in Pediatric Patients: A Systematic Review and Meta-Analysis

Air-Q® (air-Q) is a supraglottic airway device which can be used as a guidance of intubation in pediatric as well as in adult patients. We evaluated the efficacy and safety of air-Q compared to other airway devices during general anesthesia in pediatric patients by conducting a systematic review and meta-analysis. A total of 10 studies including 789 patients were included in the final analysis. Compared with other supraglottic airway devices, air-Q showed no evidence for a difference in leakage pressure and insertion time. The ease of insertion was significantly lower than other supraglottic airway devices. The success rate of intubation was significantly lower than other airway devices. However, fiberoptic view was better through the air-Q than other supraglottic airway devices. Therefore, air-Q could be a safe substitute for other airway devices and may provide better fiberoptic bronchoscopic view.

Transcranial Motor-Evoked Potentials Are More Readily Acquired Than Somatosensory-Evoked Potentials in Children Younger Than 6 Years

BACKGROUND

There is a general belief that somatosensory-evoked potentials (SSEPs) are more easily obtained than transcranial motor-evoked potentials (TcMEPs) in children younger than 6 years. We tested this assumption and the assumption that motor-evoked potentials are rarely obtained in children younger than 2 years.

METHODS

The records of all patients who were monitored during surgical procedures between April 1, 2010, and June 30, 2013, were reviewed and those who were younger than 72 months at the time of surgery were identified and analyzed for the rate of obtaining clinically useful SSEPs and motor-evoked potentials. Subgroup analysis was performed by age.

RESULTS

A total of 146 patients were identified, 9 had SSEPs without TcMEPs monitored, 117 had both TcMEPs and SSEPs monitored, and the remainder had only electromyographic monitoring. All patients who were to have TcMEPs recorded received a total IV anesthetic. Among the 117 patients who had both SSEPs and TcMEPs monitored, clinically relevant TcMEPs were obtained more frequently than SSEPs (110/117 vs 89/117; χ = 14.82; P = 0.00012). There were significant differences between the rates of obtaining SSEPs and TcMEPs in the 0- to 23-month (P = 0.0038) and 24- to 47-month (P = 0.0056) age groups. Utilization of a double-train stimulation technique facilitated obtaining TcMEPs in the youngest patients.

CONCLUSIONS

TcMEPs can be obtained more easily than SSEPs in patients younger than 72 months if a permissive anesthetic technique is used. The success rate for obtaining TcMEPs can be further enhanced by the use of a temporal facilitation (double-train) stimulation technique.

Immediate postoperative pain level from lumbar arthrodesis following epidural infiltration of morphine sulfate

Objective

To evaluate the pain level in patients treated with epidural infusion of morphine sulfate in a single dose, after a surgical procedure to perform lumber arthrodesis.

Methods

Forty patients underwent posterolateral lumbar arthrodesis or intersomatic lumbar arthrodesis via a posterior route at one, two or three levels. They were prospectively randomized into two groups of 20. In the first group (study group), 2 mg of morphine sulfate diluted in 10 mL of physiological serum was infiltrated into the epidural space, through the laminectomy area. The second group (controls) did not receive analgesia. The patients were asked about their pain levels before and after the operation, using a visual analog scale (VAS).

Results

It was found that the patients presented a significant diminution of pain as shown by the VAS. From before to after the operation, it decreased by an average of 4.7 points (p = 0.0001), which corresponded to 53.2% (p = 0.0001).

Conclusion

Application of 2 mg of morphine sulfate in a single epidural dose was shown to be a good technique for pain therapy following lumbar spinal surgery.

Translating mechanisms of neuroprotection, regeneration, and repair to treatment of spinal cord injury

One of the big challenges in neuroscience that remains to be understood is why the central nervous system is not able to regenerate to the extent that the peripheral nervous system does. This is especially problematic after traumatic injuries, like spinal cord injury (SCI), since the lack of regeneration leads to lifelong deficits and paralysis. Treatment of SCI has improved during the last several decades due to standardized protocols for emergency medical response teams and improved medical, surgical, and rehabilitative treatments. However, SCI continues to result in profound impairments for the individual. There are many processes that lead to the pathophysiology of SCI, such as ischemia, vascular disruption, neuroinflammation, oxidative stress, excitotoxicity, demyelination, and cell death. Current treatments include surgical decompression, hemodynamic control, and methylprednisolone. However, these early treatments are associated with modest functional recovery. Some treatments currently being investigated for use in SCI target neuroprotective (riluzole, minocycline, G-CSF, FGF-2, and polyethylene glycol) or neuroregenerative (chondroitinase ABC, self-assembling peptides, and rho inhibition) strategies, while many cell therapies (embryonic stem cells, neural stem cells, induced pluripotent stem cells, mesenchymal stromal cells, Schwann cells, olfactory ensheathing cells, and macrophages) have also shown promise. However, since SCI has multiple factors that determine the progress of the injury, a combinatorial therapeutic approach will most likely be required for the most effective treatment of SCI.