The PAC (Post-operative Airway Compromise) score - First steps to Develop a Post-Surgery Tool for the Assessment of Upper Airway-related Complications following Anterior Cervical Spine Surgery

BACKGROUND

Acute upper airway compromise is a rare but catastrophic complication after anterior cervical discectomy and fusion (ACDF). This study aims to develop a score to identify patients at risk for acute postoperative airway compromise (PAC).

METHODS

Potential risk factors for acute PAC were selected by a modified Delphi process. Ten patients with acute PAC were identified out of 1,466 patients who underwent elective ACDF between July 2014 - May 2019. A comparison group was created by a randomized selection process (non-PAC group). Associated factors with PAC and a p-value <.10 were entered into a logistic regression model and coefficients contributed each risk factor's overall score. Calibration of the model was evaluated by Hosmer-Lemeshow (H-L) goodness-of-fit test. Quantitative discrimination was calculated and the final model was internally validated with bootstrap sampling.

RESULTS

We identified 18 potential risk factors from our Delphi process, of which 6 factors demonstrated a significant association with airway compromise: age >65 years, current smoking status, ASA >2, history of a bleeding disorder, surgery of upper subaxial cervical spine (>C4), and duration of surgery >179 min. The final prediction model included five predictors with very strong performance characteristics. These five factors formed the PAC-Score (PACS) which had a range from 0 to 100. A score of 20 yielded the greatest balance of sensitivity (80%) and specificity (88%).

CONCLUSIONS

The acute Postoperative Airway Compromise Score (PACS) demonstrates strong performance characteristics. The PAC score may help identify patients at risk for upper airway compromise caused by surgical site abnormalities.

Associations between air pollutants and blood pressure in an ethnically diverse cohort of adolescents in London, England

Longitudinal evidence on the association between air pollution and blood pressure (BP) in adolescence is scarce. We explored this association in an ethnically diverse cohort of schoolchildren. Sex-stratified, linear random-effects modelling was used to examine how modelled residential exposure to annual average nitrogen dioxide (NO2), particulate matter (PM2.5, PM10) and ozone (O3), measures in μg/m3, associated with blood pressure. Estimates were based on 3,284 adolescents; 80% from ethnic minority groups, recruited from 51 schools, and followed up from 11-13 to 14-16 years old. Ethnic minorities were exposed to higher modelled annual average concentrations of pollution at residential postcode level than their White UK peers. A two-pollutant model (NO2 & PM2.5), adjusted for ethnicity, age, anthropometry, and pubertal status, highlighted associations with systolic, but not diastolic BP. A μg/m3 increase in NO2 was associated with a 0.30 mmHg (95% CI 0.18 to 0.40) decrease in systolic BP for girls and 0.19 mmHg (95% CI 0.07 to 0.31) decrease in systolic BP for boys. In contrast, a 1 μg/m3 increase in PM2.5 was associated with 1.34 mmHg (95% CI 0.85 to 1.82) increase in systolic BP for girls and 0.57 mmHg (95% CI 0.04 to 1.03) increase in systolic BP for boys. Associations did not vary by ethnicity, body size or socio-economic advantage. Associations were robust to adjustments for noise levels and lung function at 11-13 years. In summary, higher ambient levels of NO2 were associated with lower and PM2.5 with higher systolic BP across adolescence, with stronger associations for girls.

Air pollution and trajectories of adolescent conduct problems: the roles of ethnicity and racism; evidence from the DASH longitudinal study

PURPOSE

No known UK empirical research has investigated prospective associations between ambient air pollutants and conduct problems in adolescence. Ethnic minority children are disproportionately exposed to structural factors that could moderate any observed relationships. This prospective study examined whether exposure to PM2.5 and NO2 concentrations is associated with conduct problems in adolescence, and whether racism or ethnicity moderate such associations.

METHODS

Longitudinal associations between annual mean estimated PM2.5 and NO2 concentrations at the residential address and trajectories of conduct problems, and the potential influence of racism and ethnicity were examined school-based sample of 4775 participants (2002-2003 to 2005-2006) in London, using growth curve models.

RESULTS

Overall, in the fully adjusted model, exposure to lower concentrations of PM2.5 and NO2 was associated with a decrease in conduct problems during adolescence, while exposure to higher concentrations was associated with a flattened trajectory of conduct symptoms. Racism amplified the effect of PM2.5 (β = 0.05 (95% CI 0.01 to 0.10, p < 0.01)) on adolescent trajectories of conduct problems over time. At higher concentrations of PM2.5, there was a divergence of trajectories of adolescent conduct problems between ethnic minority groups, with White British and Black Caribbean adolescents experiencing an increase in conduct problems over time.

CONCLUSION

These findings suggest that the intersections between air pollution, ethnicity, and racism are important influences on the development of conduct problems in adolescence.

Independent Predictors of Revision Lumbar Fusion Outcomes and the Impact of Spine Surgeon Variability: Does It Matter Whether the Primary Surgeon Revises?

BACKGROUND

There is a paucity of information regarding treatment strategies and variables affecting outcomes of revision lumbar fusions.

OBJECTIVE

To evaluate the influence of primary vs different surgeon on functional outcomes of revisions.

METHODS

All elective lumbar fusion revisions, March 2018 to August 2019, were retrospectively categorized as performed by the same or different surgeon who performed the primary surgery. Oswestry Disability Index (ODI) and clinical variables were collected. Multiple logistic regression identified multivariable-adjusted odds ratio (OR) of independent variables analyzed.

RESULTS

Of the 130 cases, 117 (90%) had complete data. There was a slight difference in age in the same (median: 59; interquartile range [IQR], 54-66) and different surgeon (median: 67; IQR, 56-72) groups (P = .02); all other demographic variables were not significantly different (P > .05). Revision surgery with a different surgeon had an ODI improvement (median: 8; IQR, 2-14) greater than revisions performed by the same surgeon (median: 1.5; IQR, -3 to 10) (P < .01). Revisions who achieved minimum clinically important difference (MCID) performed by different surgeon (59.7%) were also significantly greater than the ones performed by the same surgeon (40%) (P = .042). Multivariate analysis demonstrated that a different surgeon revising (OR, 2.37; [CI]: 1.007-5.575, P = .04) was an independent predictor of MCID achievement, each additional 2 years beyond the last surgery conferred a 2.38 ([CI]: 1.36-4.14, P < .01) times greater odds of MCID achievement, and the anterior lumbar interbody fusion approach decreased the chance of achieving MCID (OR, 0.19; [CI]: 0.04-0.861, P = .03).

CONCLUSION

All revision lumbar spinal fusion approaches may not achieve the same outcomes. This analysis suggests that revision surgeries may have better outcomes when performed by a different surgeon.

Space-Occupying Lesions of the Retropharyngeal Space: An Anatomical Study With Application to Postoperative Retropharyngeal Hematomas

STUDY DESIGN

Cadaver study.

OBJECTIVE

The retropharyngeal space's (RPS's) clinical relevance is apparent in anterior cervical spine surgery with respect to postoperative hematoma, which can cause life-threatening airway obstruction. This cadaver study aims to establish guidance toward a better understanding of the tolerance of the RPS to accommodate fluid accumulation.

METHODS

Five fresh-frozen cadavers were dissected in the supine position. A digital manometer and a 20 Fr Foley catheter were inserted into the RPS via an anterolateral approach. While inflating the Foley catheter, the position of the esophagus/trachea was documented using fluoroscopy, and the retropharyngeal pressure was measured. We quantified the volume required to deviate the esophagus/trachea >1 cm from its original position using fluoroscopy. We also recorded the volume required to cause a visible change to the normal neck contour.

RESULTS

A mean volume of 12.5 mL (mean pressure 1.50 mm Hg) was needed to cause >1 cm of esophageal deviation. Tracheal deviation was encountered at a mean volume of 20.0 mL (mean pressure of 2.39 mm Hg). External visible clinical neck contour changes were apparent at a mean volume of 39 mL.

CONCLUSION

A relatively small volume of fluid in the RPS can cause the esophagus/trachea to radiographically deviate. The esophagus is the structure in the RPS to be most influenced by mass effect. The mean volume of fluid required to cause clinically identifiable changes to the normal neck contour was nearly double the volume required to cause 1 cm of esophageal/tracheal deviation in a cadaver model.

Are Lumbar Fusion Guidelines Followed? A Survey of North American Spine Surgeons

OBJECTIVE

To evaluate the use of guidelines for lumbar spine fusions among spine surgeons in North America.

METHODS

An anonymous survey was electronically sent to all AO Spine North America members. Survey respondents were asked to indicate their opinion surrounding the suitability of instrumented fusion in a variety of clinical scenarios. Fusion indications in accordance with North America Spine Society (NASS) guidelines for lumbar fusion were considered NASS-concordant answers. Respondents were considered to have a NASS-concordant approach if ≥ 70% (13 of 18) of their answers were NASS-concordant answers. Comparisons were performed using bivariable statistics.

RESULTS

A total of 105 responses were entered with complete data available on 70. Sixty percent of the respondents (n = 42) were considered compliant with NASS guidelines. NASS-discordant responses did not differ between surgeons who stated that they include the NASS guidelines in their decision-making algorithm (5.10 ± 1.96) and those that did not (4.68 ± 2.09) (p = 0.395). The greatest number of NASS-discordant answers in the United States. was in the South (5.75 ± 2.09), with the lowest number in the Northeast (3.84 ± 1.70) (p < 0.01). For 5 survey items, rates of NASS-discordant answers were ≥ 40%, with the greatest number of NASS-discordant responses observed in relation to indications for fusion in spinal deformity (80%). Spine surgeons utilizing a NASS-concordant approach had a significant lower number of NASS-discordant answers for synovial cysts (p = 0.03), axial low back pain (p < 0.01), adjacent level disease (p < 0.01), recurrent stenosis (p < 0.01), recurrent disc herniation (p = 0.01), and foraminal stenosis (p < 0.01).

CONCLUSION

This study serves an important role in clarifying the rates of uptake of clinical practice guidelines in spine surgery as well as to identify barriers to their implementation.

Surgical Treatment of Ossifications of the Cervical Anterior Longitudinal Ligament: A Retrospective Cohort Study

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

The study aims to evaluate anterior cervical discectomy and fusion (ACDF) in the treatment of patients with ossification of the anterior longitudinal ligament (OALL).

METHODS

We retrospectively reviewed cases performed at our institution between January 2015 and December 2018; adult (age ≥18 years) patients who underwent anterior cervical decompression and fusion in the presence of dysphagia and OALL. Ten patients (9 male, 1 female, mean age 64.4 years) with OALL who underwent ACDF were included. Charts were reviewed for demographics and comorbidities. Primary outcomes assessed were intra- and postoperative complications. Secondary outcomes were fusion rates, instrumentation failure, postsurgical instability/deformity, and readmission rates.

RESULTS

The average duration of symptoms prior to surgery was 12.3 months. All patients presented with dysphagia (mean Bazaz score 2.0). The average number of levels with OALL was 4.7 (±1.67). All patients underwent ACDF and 3 patients underwent additional posterior cervical fusion for kyphotic deformity correction or when extensive laminectomy was required. We did not encounter any intraoperative complications. Eight patients (72%) had solid fusion demonstrated on the lateral x-rays and no evidence of progressive kyphotic deformity. We did not encounter any instrumentation failure or loosening. Two patients developed recurrence of dysphagia (Bazaz scores 2 and 3 respectively).

CONCLUSION

ACDF for OALL with dysphagia and concomitant myelopathy in our small series of 10 patients demonstrate good fusion and clinical outcomes. Larger studies will be necessary to determine the optimal treatment for patients with dysphagia due to OALL.

Spinal ganglion cyst presenting with radiculopathy: diagnostic challenges and differential

INTRODUCTION

Ganglion cysts are benign soft tissue lesions, usually arising from periarticular connective tissue. These are very rarely reported in the spine, but when seen can cause radiculopathy or myelopathy.

CASE PRESENTATION

A 68-year-old female patient presented with worsening radiculopathy and right foot drop and imaging noted a right L5-S1 foraminal mass. The lesion was gross totally resected. Histological analysis revealed myxoid degeneration and inflammation, without a synovial lining, consistent with ganglion cyst.

DISCUSSION

While uncommon, intra-foraminal ganglion cysts can be distinguished from synovial cysts through imaging and histology and are typically amenable to surgical resection. Greater knowledge and insight about differentiating ganglion versus synovial cyst may prevent resection of facet joints and prevent a fusion procedure.

Risk Factors Associated with 90-Day Readmissions Following Occipitocervical Fusion-A Nationwide Readmissions Database Study

BACKGROUND

Occipitocervical fusion (OCF) procedures are increasing due to an aging population and the prevalence of trauma, rheumatoid arthritis, and tumors. Reoperation rates and readmission risk factors for cervical fusions have been established, but in relation to OCF they have not been explored. This study investigates the patterns of readmissions and complications following OCF using a national database.

METHODS

The 2016 U.S. Nationwide Readmissions Database was used for sample collection. Adults (>18 years) who underwent OCF were identified using the 2016 ICD-10 coding system, and we examined the readmission rates (30-day and 90-day) and reoperation rates.

RESULTS

Between January and September 2016, a total of 477 patients underwent OCF; the 30-day and 90-day readmission rates were 10.4% and 22.4%, respectively. The 90-day reoperation rate related to the index surgery was 5.7%. Mean age (68.58 years) was significantly greater in the readmitted group versus nonreadmitted group (61.76 years) (P < 0.001). The readmitted group had a significantly higher Charlson Comorbidity Index and Elixhauser Comorbidity Index (5.00 and 2.41, respectively) than the nonreadmitted group (3.25 and 1.15, respectively; P < 0.001). Nonelective OCF showed a higher readmission rate (29.18%) versus elective OCF (12.23%) (P < 0.001). Medicare and Medicaid patients showed the highest rates of readmission (27.27% and 20.41%, respectively). Readmitted patients had higher total health care costs.

CONCLUSIONS

Nonelective OCF was found to have a readmission rate of almost 2½× that of elective OCF. Understanding risk factors associated with OCF will help with operative planning and patient optimization.

Pathophysiologic Mechanisms of Concussion, Development of Chronic Traumatic Encephalopathy, and Emerging Diagnostics: A Narrative Review

Pathophysiological mechanisms and cascades take place after a mild traumatic brain injury (mTBI) that can cause long-term sequelae, including chronic traumatic encephalopathy in patients with multiple concurrent TBIs. As diagnostic imaging has become more advanced, microanatomical changes present after mTBI may now be more readily visible. In this narrative review, the authors discuss emerging diagnostics and findings in mTBI through advanced imaging, electroencephalograms, neurophysiologic processes, Q2 biochemical markers, and clinical tissue tests in an effort to help osteopathic physicians to understand, diagnose, and manage the pathophysiology behind mTBI, which is increasingly prevalent in the United States.

The new onset of dysphagia four years after anterior cervical discectomy and fusion: Case report and literature review

Background:

Dysphagia is a common complication immediately following anterior cervical spine surgery. However, its onset more than 1-year postoperatively is rare.

Case Description:

A 45-year-old male initially underwent a C3-4 and C5-6 anterior cervical discectomy and fusion (ACDF). At age 49, 4 years later, he presented with worsening dysphagia accompanied by neck and right upper extremity pain. Radiographs demonstrated an extruded left C3 screw, which had migrated into the prevertebral soft tissues at the C4-C5 level; there was also loosening of the right C3 screw. The subsequent barium swallow study revealed that the screw was embedded in the pharyngeal wall. The patient required a two-stage operation; first, to remove the anterior instrumentation, and second, to perform a posterior instrumented C2-T2 fusion.

Conclusion:

A barium swallow study and other dynamic imaging are a valuable component of the diagnostic workup and therapeutic intervention to evaluate the delayed onset dysphagia following an ACDF.

A Review of Lumbar Radiculopathy, Diagnosis, and Treatment

We review the epidemiology, etiology, symptomatology, clinical presentation, anatomy, pathophysiology, workup, diagnosis, non-surgical and surgical management, postoperative care, outcomes, long-term management, and morbidity of lumbar radiculopathy. We review when outpatient conservative management is appropriate and "red flag" warning symptoms that would necessitate an emergency evaluation. Diagnostic modalities, including magnetic resonance imaging (MRI), computerized tomography (CT), contrast myelogram, electromyogram (EMG), and nerve conduction velocity (NCV), are involved in the diagnosis and decision-making are discussed. Treatment of lumbar radiculopathy requires a multimodal and multispecialty team. We review indications for the involvement of other professionals, including physical therapy (PT), occupational therapy (OT), physical and rehabilitation medicine (PMR), and pain management.

Primary Spinal Astrocytomas: A Literature Review

Primary spinal astrocytoma is a subtype of glioma, the most common spinal cord tumor found in the intradural intramedullary compartment. Spinal astrocytomas account for 6-8% of all spinal cord tumors and are primarily low grade (World Health Organization grade I (WHO I) or WHO II). They are seen in both the adult and pediatric population with the most common presenting symptoms being back pain, sensory dysfunction, or motor dysfunction. Magnetic Resonance Imaging (MRI) with and without gadolinium is the imaging of choice, which usually reveals a hypointense T1 weighted and hyperintense T2 weighted lesion with a heterogeneous pattern of contrast enhancement. Further imaging which may aid in surgical planning includes computerized tomography, diffusion tensor imaging, and tractography. Median survival in spinal cord astrocytomas ranges widely. The factors most significantly associated with poor prognosis and shorter median survival are older age at initial diagnosis, higher grade lesion based on histology, and extent of resection. The mainstay of treatment for primary spinal cord astrocytomas is surgical resection, with the goal of preservation of neurologic function, guided by intraoperative neuromonitoring. Adjunctive radiation has been shown beneficial and may increase overall survival. The role of adjunctive chemotherapy is employed, however, its benefit has not been clearly defined. Primary spinal cord astrocytomas are rare and challenging to treat. The gold standard treatment is surgical resection. Second-line treatments include radiation and chemotherapy, although, the optimal regimen for adjunctive therapy has not yet been clearly defined.

Effectiveness of Method of Repair of Incidental Thoracic and Lumbar Durotomies: A Comparison of Direct Versus Indirect Repair

Introduction

Incidental durotomy (ID) is a well-known complication in spine surgery. Surveys have not identified a consensus for repair method among neurosurgeons. IDs may lead to complications such as cerebrospinal fluid (CSF) fistula, which may predispose patients to infection, additional procedures, increased length of stay and morbidity. This study aims to compare durotomy repair methods with clinical outcomes.

Methods

The neurosurgery database at a single institution, Arrowhead Regional Medical Center, was screened for all patients who underwent thoracic and lumbar spine surgery from 2007-2017. Retrospective chart review of operative reports identified patients with an ID. Data collection included: length of stay, infection, additional procedures, time lying flat, CSF fistula formation (primary endpoint) with analysis using t-tests.

Results

A total of 384 patients underwent initial analysis. Of the 384 patients, 25 had an incidental durotomy based on operative reports. Four patients were excluded from this subset: two were repaired with muscle graft (low N), two were excluded for unclear repair method. The remaining 21 were stratified into two groups, those repaired directly with suture with or without adjunct (N=9) and those repaired indirectly with sealant (N=12). No patients developed a CSF fistula. The indirect group had a length of stay of six days, while the direct group had a length of stay of four days, p=0.184. Two of the nine patients in the direct group and two of the twelve patients in the indirect group developed an infection, p=0.586.

Conclusion

No patients developed CSF fistulas. Secondary endpoints of length of stay and infection rate did not differ. This study was unable to determine if direct versus indirect repair was a more effective repair method for ID. It is possible that if an incidental durotomy is identified and repaired with a water-tight seal, the repair method does not affect the outcome. It is up to the surgeon to individualize repair based on ability and circumstances.

Efficacy of Trauma Catheter and Mushroom Tip Catheter in Evacuation of Chronic Subdural Hematoma and Complications of Drain Placement

Objective The aim of this study was to assess the efficacy and complications of trauma catheter versus mushroom tip catheter placement in the evacuation of chronic subdural hematoma via twist drill craniostomy with closed system drainage. Background Chronic subdural hematoma (cSDH) is one of the most frequent neurosurgical pathologies in patients >70 years of age with an estimated incidence of 8.2 per 100,000 people per year. The most common risk factors for cSDH are advanced age, alcohol abuse, seizures, cerebrospinal fluid (CSF) shunts, coagulopathies, blood thinners, and patients at risk for falling. Twist drill craniostomy can be performed at the bedside under local anesthesia, making it an attractive treatment option, especially in poly-morbid patients who are poor surgical candidates. A closed drainage system is placed at the time of surgery to allow continuous drainage and promote postoperative brain expansion. Despite the increasing prevalence, limited literature exists to guide surgical management, particularly in terms of drain management and selection of catheter.  Methods This is a retrospective review of 205 patients from January 2007 to May 2017 at two-level high volume centers for the evaluation and treatment of cSDH. Inclusion criteria include patients >18 years of age with the radiographic presence of a subdural hematoma for greater than three weeks. All patients were managed with either a trauma catheter or mushroom tip catheter. All patients received computed tomography (CT) of the head without contrast prior to subdural drain placement and within 24 hours after subdural drain removal. Exclusion criteria include patients <18 years of age and patients with depressed skull fractures, vascular malformations, subdural empyema, subdural hygroma, or who initially underwent open craniotomy or burr-hole craniotomy. Results Drain efficiency in evacuating the cSDH was assessed using both radiographic and clinical markers. Analysis of 205 patients treated by twist drill craniostomy and the subsequent closed system drainage utilizing either the mushroom tip catheter or trauma catheter revealed that neither catheter was superior in producing a statistically significant change in the maximum thickness of the cSDH (p = 0.35) and midline shift (p = 0.45). Furthermore, when assessing patients clinically via utilization of the Glasgow Coma Scale (GCS), both the trauma catheter and the mushroom catheter did not show a statistically significant difference in improving GCS after the evacuation of the cSDH (p = 0.35). Neither catheter was associated with an increased incidence of hemorrhage with drain placement requiring open surgery (p = 0.12), need for additional drain placement (p = 0.13) or decline in GCS with intervention (p = 0.065). Conclusion Analysis of the 205 patients treated by twist drill craniostomy with closed system drainage for the evacuation of chronic subdural hematoma utilizing either the mushroom tip or trauma catheters revealed that neither catheter was statistically significant in radiographic or clinical improvement in evacuating cSDH. Furthermore, neither catheter was found to be associated with an increased complication risk.

The neurosurgical wound and factors that can affect cosmetic, functional, and neurological outcomes

Surgically accessing pathological lesions located within the central nervous system (CNS) frequently requires creating an incision in cosmetic regions of the head and neck. The biggest factors of surgical success typically tend to focus on the middle portion of the surgery, but a vast majority of surgical complications tend to happen towards the end of a case, during closure of the surgical site incisions. One of the most difficult complications for a surgeon to deal with is having to take a patient back to the operating room for wound breakdowns and, even worse, wound or CNS infections, which can negate all the positive outcomes from the surgery itself. In this paper, we discuss the underlying anatomy, pharmacological considerations, surgical techniques and nutritional needs necessary to help facilitate appropriate wound healing. A successful surgery begins with preoperative planning regarding the placement of the surgical incision, being cognizant of cosmetics, and the effects of possible adjuvant radiation therapy on healing incisions. We need to assess patient's medications and past medical history to make sure we can optimise conditions for proper wound reepithelialisation, such as minimizing the amount of steroids and certain antibiotics. Contrary to harmful medications, it is imperative to optimise nutritional intake with adequate supplementation and vitamin intake. The goals of this paper are to reinforce the mechanisms by which surgical wounds can fail, leading to postoperative complications, and to provide surgeons with the reminder and techniques that can help foster a more successful surgical outcome.

Use of a Pediatric Craniotome Drill for Cervical and Thoracic Spine Decompression: Safety and Efficacy

BACKGROUND

Laminectomy, using a high-speed drill with an unprotected cutting drill bit, can be rapid and effective, but it has been associated with known complications. Another technique uses a pediatric craniotome drill with the footplate attachment. At present, there are no studies comparing clinical outcomes between these 2 stated decompressive techniques.

METHODS

A retrospective review was conducted at a single institution. Two cohorts of patients were considered based on the technical method of laminectomy for decompression. One group had decompression with utilization of a high-speed drill, whereas the other group had decompression with a pediatric craniotome drill with a footplate attachment. The outcomes from each group were compared based on the length of operation, estimated blood loss, and associated complications.

RESULTS

A total of 91 patients were included in the final analysis. Forty-five of the patients underwent laminectomy using a footplate and 46, using a high-speed drill. The footplate group was associated with significantly shorter operative time (159 vs. 205 minutes; P = 0.008). In addition, the footplate technique demonstrated less estimated blood loss (254 vs. 349 mL), and less incidence of durotomies (2.2% vs. 10.9%); however, neither of these 2 outcomes achieved statistical significance.

CONCLUSIONS

Despite being an older technique, there was a shorter operative time in the footplate group without increased blood loss or incidence of durotomy. Although comparable results are operator dependent, this technique is a safe alternative for performing cervical and thoracic laminectomies.

Resolution of Tachyarrhythmia Following Posterior Fossa Decompression Surgery for Chiari Malformation Type I

INTRODUCTION

Chiari malformation (CM) type I commonly presents with symptoms such as tussive headaches, paresthesias, and, in severe cases, corticobulbar dysfunction. However, patients may present with atypical symptoms lending to the complexity in this patient population. We present a case of a CM patient presenting with atypical cardiac symptoms and arrhythmias, all of which resolved after surgical decompression.

CASE DESCRIPTION

A 31-year-old female presented with atypical chest pain, palpitations, tachycardia, headaches, and dizziness for 2 years. Multiple antiarrhythmics and ultimately cardiac ablation procedure proved to be ineffective. Magnetic resonance imaging revealed CM, and the patient ultimately underwent surgical decompression with subsequent resolution of her symptoms.

CONCLUSION

The surgical management of CM patients presenting with atypical symptoms can be challenging and often lead to delays in intervention. To our knowledge this is the only reported case of a patient presenting with tachyarrhythmia and atypical chest pain with resolution after Chiari decompression. We believe the dramatic improvement documented in the present case should serve to advance Chiari decompression in CM patients presenting with refractory tachyarrhythmia in whom no other discernable cause has been elucidated. Further studies are needed to better correlate the findings and to hopefully establish a criteria for patients that will likely benefit from surgical decompression.

Pial-Dural Intracranial Arteriovenous Fistula with Flow-Associated Aneurysmal Rupture-Case Report with Review of Literature and Proposal on the Mechanism of Hemorrhage and Treatment Options

BACKGROUND

Vascular anomalies in the form of dural arteriovenous fistulas (DAVFs), arteriovenous malformations, and aneurysms are well described in the literature. Pial arteriovenous fistulas (PAVFs) are described to a lesser extent in the literature. When these anomalies are combined, diagnosis and treatment become complex.

CASE DESCRIPTION

A 55-year-old man presented with PAVF/DAVF with a ruptured flow-related aneurysm in the distal left posterior inferior cerebellar artery, which required surgical clipping and disconnection. We performed a PubMed search of all identifiable cases of PAVFs in adults. We then identified which cases had components of DAVFs and flow-related aneurysms. We identified 51 PAVF cases and identified which patients presented with hemorrhage and the treatment modalities of all cases. Of 51 cases identified, 4 were a DAVF/FRA, and 5 were a PAVF/DAVF. One case of PAVF/DAVF/FRA was identified.

CONCLUSIONS

The exact mechanism of PAVF/DAVF formation is unknown. Hemorrhage predilection of PAVF/DAVF is more difficult to predict than a sole fistula, likely secondary to the complex flow dynamics. To our knowledge, this literature review is the largest review to date regarding PAVFs in adult patients and can provide insight into decision making when evaluating treatment options.

Neutrophil gelatinase-associated lipocalin is a biomarker of acute-on-chronic liver failure and prognosis in cirrhosis

BACKGROUND & AIMS

Acute-on-chronic liver failure (ACLF) is a syndrome that occurs in cirrhosis characterized by organ failure(s) and high mortality rate. There are no biomarkers of ACLF. The LCN2 gene and its product, neutrophil gelatinase-associated lipocalin (NGAL), are upregulated in experimental models of liver injury and cultured hepatocytes as a result of injury by toxins or proinflammatory cytokines, particularly Interleukin-6. The aim of this study was to investigate whether NGAL could be a biomarker of ACLF and whether LCN2 gene may be upregulated in the liver in ACLF.

METHODS

We analyzed urine and plasma NGAL levels in 716 patients hospitalized for complications of cirrhosis, 148 with ACLF. LCN2 expression was assessed in liver biopsies from 29 additional patients with decompensated cirrhosis with and without ACLF.

RESULTS

Urine NGAL was markedly increased in ACLF vs. no ACLF patients (108(35-400) vs. 29(12-73)μg/g creatinine; p<0.001) and was an independent predictive factor of ACLF; the independent association persisted after adjustment for kidney function or exclusion of variables present in ACLF definition. Urine NGAL was also an independent predictive factor of 28day transplant-free mortality together with MELD score and leukocyte count (AUROC 0.88(0.83-0.92)). Urine NGAL improved significantly the accuracy of MELD in predicting prognosis. The LCN2 gene was markedly upregulated in the liver of patients with ACLF. Gene expression correlated directly with serum bilirubin and INR (r=0.79; p<0.001 and r=0.67; p<0.001), MELD (r=0.68; p<0.001) and Interleukin-6 (r=0.65; p<0.001).

CONCLUSIONS

NGAL is a biomarker of ACLF and prognosis and correlates with liver failure and systemic inflammation. There is remarkable overexpression of LCN2 gene in the liver in ACLF syndrome.

LAY SUMMARY

Urine NGAL is a biomarker of acute-on-chronic liver failure (ACLF). NGAL is a protein that may be expressed in several tissues in response to injury. The protein is filtered by the kidneys due to its small size and can be measured in the urine. Ariza, Graupera and colleagues found in a series of 716 patients with cirrhosis that urine NGAL was markedly increased in patients with ACLF and correlated with prognosis. Moreover, gene coding NGAL was markedly overexpressed in the liver tissue in ACLF.

Measurement of the charged-pion polarizability

The COMPASS collaboration at CERN has investigated pion Compton scattering, π(-)γ→π(-)γ, at center-of-mass energy below 3.5 pion masses. The process is embedded in the reaction π(-)Ni→π(-)γNi, which is initiated by 190 GeV pions impinging on a nickel target. The exchange of quasireal photons is selected by isolating the sharp Coulomb peak observed at smallest momentum transfers, Q(2)<0.0015  (GeV/c)(2). From a sample of 63,000 events, the pion electric polarizability is determined to be α(π)=(2.0±0.6(stat)±0.7(syst))×10(-4)  fm(3) under the assumption α(π)=-β(π), which relates the electric and magnetic dipole polarizabilities. It is the most precise measurement of this fundamental low-energy parameter of strong interaction that has been addressed since long by various methods with conflicting outcomes. While this result is in tension with previous dedicated measurements, it is found in agreement with the expectation from chiral perturbation theory. An additional measurement replacing pions by muons, for which the cross-section behavior is unambiguously known, was performed for an independent estimate of the systematic uncertainty.

Epidemiology and outcome of sepsis syndromes in Italian ICUs: a muticentre, observational cohort study in the region of Piedmont

BACKGROUND

Sepsis is an important cause of mortality and morbidity in the intensive care unit (ICU). We performed a study to describe the epidemiology of sepsis syndromes in patients admitted to ICUs of the Piedmont region.

METHODS

In this prospective, multicentre, observational study, all 3902 patients admitted to a network of 24 ICUs from 17 hospitals during a 180 day period (April 3-September 29, 2006) were included. Patients were followed from the first day of admission until death or ICU discharge.

RESULTS

The incidence of sepsis during the ICU stay was 11.4% (N.=446), corresponding to an incidence of 25 cases/100,000 inhabitants/year; 141 (31.6%) patients had only sepsis, 160 patients had severe sepsis (35.9%) and 145 patients (32.5%) had septic shock In 227 patients (50.9%), sepsis was observed within 48 hours after admission to the ICU, and 219 patients (49.1%) developed ICU-acquired sepsis. The main sources of infection were the lungs, abdomen, and urinary tract. ICU mortality was higher (41.3 vs. 17.3%, P<0.0001) and the median ICU length of stay longer (15 vs. 2 days, P<0.0001) in patients with sepsis than in those without sepsis. The mortality rate increased with the severity of sepsis. ICU-acquired sepsis was associated with higher ICU mortality rates than sepsis occurring within 48 hours of ICU admission (49.8 vs. 33.0%, P<0.0001).

CONCLUSION

Sepsis is a common occurrence in critically ill patients. Our data underscore the regional variability in the epidemiology and outcome of sepsis syndromes and may be useful to guide appropriate resource allocation.

First measurement of chiral dynamics in π- γ → π- π- π+

The COMPASS Collaboration at CERN has investigated the π- γ → π- π- π+ reaction at center-of-momentum energy below five pion masses, sqrt[s]<5m(π), embedded in the Primakoff reaction of 190 GeV pions impinging on a lead target. Exchange of quasireal photons is selected by isolating the sharp Coulomb peak observed at smallest momentum transfers, t'<0.001  GeV2/c2. Using partial-wave analysis techniques, the scattering intensity of Coulomb production described in terms of chiral dynamics and its dependence on the 3π-invariant mass m(3π)=sqrt[s] were extracted. The absolute cross section was determined in seven bins of sqrt[s] with an overall precision of 20%. At leading order, the result is found to be in good agreement with the prediction of chiral perturbation theory over the whole energy range investigated.

Endoscopic banding for esophageal variceal bleeding: technique and patient outcome

AIM

Endoscopic variceal ligation (EVL) is recommended for the treatment of esophageal variceal bleeding. The aim of this study was to assess the most cost-effective timing of endoscopic follow-up after variceal eradication.

METHODS

Cirrhotics with esophageal varices treated between January 2008 and January 2009 until reached variceal obliteration were retrospectively analyzed for technical aspects and for outcomes.

RESULTS

Out of 127 patients treated with EVL, 103 were included. Number of sessions to achieve variceal obliteration and number of bands for each session were 2.8±1.3 (range 1-7) and 4.6±1 (range 2-7), respectively. The placement of >5 bands per session was not associated with higher incidence of complications (19.6% vs. 17.8%, P=ns). Esophageal ulcers were observed in 42% of patients when the interbanding interval was <20 days (versus 15% for interval >20 days, P<0.05). Once obliteration was achieved, varices reappeared in 28% of patients; the early appearance of small varices was not associated with bleeding.

CONCLUSION

A longer interbanding interval reduces the incidence of procedural-related complications. After variceal obliteration an early endoscopic control is not useful because it does not influence the approach and does not change the patient outcome.

Potential link between Helicobacter pylori and ischemic heart disease: does the bacterium elicit thrombosis?

Over the past fifteen years, numerous observations have linked Helicobacter pylori (H. pylori) infection to ischemic heart disease (IHD). Despite the controversial literature data, it has been postulated that if a role is plausible, it will be in the early events of the acute coronary syndrome. According to this model, we focused on the potential pathogenic mechanisms relating H. pylori to IHD like platelet aggregation and thrombosis. To identify all publications in this field, a MEDLINE search of studies published in English from 1965 to 2009 was conducted. Although very few investigations were found, these showed data of paramount importance. In particular, it has been demonstrated that some strains of H. pylori bind von Willebrand factor and interact with glycoprotein Ib to induce platelet aggregation in humans. In experiments from animal models, such infection promoted the formation of platelet aggregates by both a marked increase in the flux of rolling leukocytes and the appearance of platelet and leukocyte-platelet aggregates in gastric venules. This aggregate formation was abrogated by antibodies against specific adhesion molecules (L- and P-selectin). The future challenge is to gain more knowledge in this field and to translate these information into clinical practice.

Quality-of-life measurement in patients with inflammatory bowel disease receiving social support

BACKGROUND

Crohn's disease and ulcerative colitis, referred to as inflammatory bowel diseases, affect mainly young adults and have an elevated morbidity and a negative effect on quality of life. This study aimed to compare the health-related quality of life between 2 randomized groups of patients with inflammatory bowel disease: (1) the supported group (SG), patients receiving social support for an 18-month period, and (2) the control group (CG), patients receiving no social support.

METHODS

Health-related quality of life was assessed at 4 moments with the Portuguese versions of the Medical Outcomes Study Short Form 36 and the Inflammatory Bowel Disease Questionnaire (IBDQ), both validated in Brazil.

RESULTS

In the SG, using analysis of variance for repeated measures complemented by the Bonferroni test positive variations were observed (1) in the Social Aspects domain, between the first and third evaluations (P = 0.044), and (2) in the Emotional Aspects domain, between the first and second and the third and fourth evaluations (P = 0.029).

CONCLUSIONS

In the sample studied, social support, measured by use of the Inflammatory Bowel Disease Questionnaire, had a positive impact on the social and emotional aspects of quality of life.

Effects of Lactobacillus GG on genes expression pattern in small bowel mucosa

BACKGROUND AND AIMS

Probiotics have been used for cure and prevention of several clinical conditions. However, further insights into the mechanism of action are needed to understand the rationale of their use. The aim of this study was to investigate the influence of Lactobacillus GG on the genetic expression patterns in the small bowel mucosa.

METHODS

Six male patients (38+/-5 years) with endoscopically proven oesophagitis were enrolled. All patients were treated for 1 month with esomeprazole and randomised to receive Lactobacillus GG or placebo. After 1 month of treatment, upper endoscopy was repeated. Biopsies of the duodenal mucosa were taken prior to and after the treatment, and the genes expression patterns were assessed using GeneChip Human U133A array. Genes with significant expression changes were selected and analysed to identify specific cellular pathways modified by Lactobacillus GG. To support the array data, 10 target genes were studied using Syber-Green PCR.

RESULTS

Microarray analysis showed that Lactobacillus GG administration determined the up- and down-regulation of 334 and 92 genes, respectively. Real-time PCR confirmed the reliability of the analysis. Lactobacillus GG mainly affected the expression of genes involved in immune response and inflammation (TGF-beta and TNF family members, cytokines, nitric oxide synthase 1, defensin alpha 1), apoptosis, cell growth and cell differentiation (cyclins and caspases, oncogenes), cell-cell signalling (ICAMs and integrins), cell adhesion (cadherins), signal transcription and transduction.

CONCLUSIONS

These data indicate that administration of Lactobacillus GG is associated with a complex genetic response of the duodenal mucosa, reflected by the up- and down-regulation of several genes involved in specific cellular pathways.

Bronchial hyperresponsiveness and analysis of induced sputum cells in Crohn's disease

With the aim of investigating the presence of latent inflammatory process in the lungs of patients with Crohn's disease, 15 patients with Crohn's disease were evaluated by spirometry, the methacholine challenge test, induced sputum, and skin tests for inhaled antigens. Serum IgE, erythrocyte sedimentation rate and hematocrit were also determined. The patients were compared with 20 healthy controls by the Mann-Whitney and Fisher exact tests. Their respiratory physical examination was normal. None had a personal or family history of clinical atopy. None had a previous history of pulmonary disease, smoking or toxic bronchopulmonary exposure. None had sinusitis, migraine, diabetes mellitus, or cardiac failure. Four (26.6%) of the patients with Crohn's disease had a positive methacholine challenge test whereas none of the 20 controls had a positive methacholine test (P = 0.026, Fisher exact test). Patients with Crohn's disease had a higher level of lymphocytes in induced sputum than controls (mean 14.59%, range 3.2-50 vs 5.46%, 0-26.92%, respectively; P = 0.011, Mann-Whitney test). Patients with Crohn's disease and a positive methacholine challenge test had an even higher percentage of lymphocytes in induced sputum compared with patients with Crohn's disease and a negative methacholine test (mean 24.88%, range 12.87-50 vs 10.48%, 3.2-21.69%; P = 0.047, Mann-Whitney test). The simultaneous findings of bronchopulmonary lymphocytosis and bronchial hyperresponsiveness in patients with Crohn's disease were not reported up to now. These results suggest that patients with Crohn's disease present a subclinical inflammatory process despite the absence of pulmonary symptoms.

Effects of oral nutritional supplementation on the intestinal mucosa of patients with AIDS

Weight loss is a major component of the clinical syndrome in patients with acquired immunodeficiency syndrome (AIDS). The impact of malnutrition on the outcome of the disease has been unappreciated in many investigations. The authors evaluated the effects of oral nutritional supplementation on the morphology and immunology of the intestinal mucosa of patients with AIDS. Twelve patients with AIDS without diarrhea or opportunistic infections, with at least 10% of body weight loss over 1 year, were submitted to anthropometric measures, peripheral blood T-lymphocyte counts, and peroral jejunal biopsy before and after oral nutritional supplementation. An industrialized peptide-based formula containing omega-3 fatty acids was given for 6 weeks. Jejunal samples were analyzed by histomorphometry, including villous-to-crypt ratio, lamina propria, and intraepithelial lymphocyte count. Immunologic assessment of the intestinal mucosa was made by indirect immunoperoxidase using monoclonal antibodies against CD3, CD4, and CD8. Seven patients with irritable bowel syndrome and two healthy volunteers were selected as a control group for histologic and immunohistochemical comparisons. After 6 weeks the patient group maintained their body weight and increased their tricipital fold. The number of peripheral blood T cells, albumin, transferrin, and the number of CD3+, CD4+, and CD8+ cells in jejunal mucosa as well as the intestinal morphometry remained stable. Oral supplementation contributed to maintaining body weight and may constitute a reasonable adjuvant therapeutic tool against AIDS progression.

Humoral intestinal immunity in systemic lupus erythematosus

Forty-five patients with systemic lupus erythematosus (SLE) underwent a cross-sectional study to evaluate intestinal secretory immunity. Peroral jejunal biopsy with histologic and immunohistochemical assessment of the mucosa were carried out in the patients and in 12 healthy volunteers. It was observed that an altered pattern of immunoglobulin-bearing plasma cells distributed in the lamina propria and complementary components were invariably present, mainly in the patients with active disease. The basement membrane of the intestinal crypt epithelium exhibited immunoglobulin and complementary deposits, similar to the lupus band test. None of the immunologic findings correlated with the medical treatment and with the peripheral blood analysis. The local changes in humoral immunity in patients with SLE did not correlate with gastrointestinal symptoms and may reflect the systemic effects of the disease.

Clinical patterns of diarrhea in AIDS. A retrospective study at the Federal University Hospital, Rio de Janeiro

Three hundred and fifty two medical records of AIDS inpatients were analysed in a retrospective study to establish the frequency, clinical patterns and etiology of AIDS-related diarrhea. Diarrhea was observed in 58.8% of the patients, being a chronic symptom in 65.7%, and the first complaint in 24.6%. The most common cause of diarrhea was coccidea and the etiology remained unknown in 56.1% of the patients. Routine stool examination was the most sensitive method in the diagnosis of diarrhea. In countries with limited resources, the use of stool examinations seems to provide appropriate clinical management. The implementation of an objective protocol could improve the etiologic diagnosis of AIDS-related diarrhea without the burden of more complex and invasive technologies.

Quantitative and qualitative changes in intestinal immunoglobulin-bearing plasma cells in jejunal mucosa of 52 HIV-infected patients

1. The purpose of the present study was to evaluate the intestinal secretory immunity of HIV-infected patients. Jejunal biopsies were obtained with a Watson capsule from 52 HIV-infected patients and compared to a control group consisting of 12 healthy subjects, matched for age and sex. IgA- and IgM-containing plasma cells were studied by immunofluorescence by two independent observers who had no knowledge of the history of the slides. 2. The IgA and IgM plasma cell density was significantly decreased in HIV-infected patients when compared to the controls (31/52 for IgA and 42/52 for IgM in the HIV group and normal density in all controls). The depletion of intestinal plasma cells was an early feature of HIV disease and did not correlate with diarrhea, enteropathogens or mucosal atrophy. Although IgA plasma cell depletion has been described in HIV infection, this is the first report of IgM cell density reduction. 3. A peripheral fluorescence pattern was observed in the intestinal cells of HIV-infected patients, contrasting with the normal cytoplasmic fluorescence pattern seen in controls. The cells presenting a rim of peripheral fluorescence in HIV disease might correspond to immature B lymphocytes. 4. The intestinal plasma cell depletion may result in hampered mucosal defense in HIV disease, and is likely to be a direct consequence of T lymphocyte function impairment. 5. The data indicate that the intestinal secretory immune system is altered in AIDS and also in the early stages of HIV disease.

Loss of mucosal CD4 lymphocytes is an early feature of HIV infection

T cell subsets in the gut mucosa are distinct populations and their imbalance in HIV has specific implications in infection. Alterations in T cell subsets in duodenal biopsies were investigated in 17 asymptomatic HIV patients, 24 AIDS patients and 10 controls with non-ulcer dyspepsia. Immunohistochemistry and immunofluorescence using MoAbs to CD3, CD4, CD8, CD68, CD45RA, CD45RO and gp120 were performed on frozen sections. In the lamina propria, there was a significant depletion of CD4+ cells at all stages of HIV, but the density of CD8 lamina propria cells was increased. Intraepithelial lymphocytes were decreased in AIDS patients. There was a significant correlation between cellular density and mucosal CD3+ lymphocytes, and between mucosal CD3+ and CD8+ lymphocytes. Although mucosal CD4,CD45RO+ 'memory' cells were decreased, CD8,CD45RO+ 'memory' cells were increased. Mucosal CD4+ lymphocyte depletion occurred early in HIV, and thus their role in mucosal protection against opportunistic infection should be revised. Mucosal CD8+ lymphocytes initially increased, but decreased when CD4 blood counts were depleted, perhaps contributing to loss of host protection against infection. Intraepithelial lymphocyte depletion may also contribute to opportunistic infection.