Samir Kashyap

Bio: Samir Kashyap is an academic researcher from Riverside University Health System - Medical Center. The author has contributed to research in topics: External ventricular drain & Traumatic brain injury. The author has an hindex of 5, co-authored 30 publications receiving 76 citations. Previous affiliations of Samir Kashyap include Arrowhead Regional Medical Center & University Health System.

Abdominal pseudocyst as a complication of ventriculoperitoneal shunt placement: Review of the literature and a proposed algorithm for treatment using 4 illustrative cases.

Abstract: Background Ventriculoperitoneal (VP) shunt placement is one of the most commonly performed procedures in neurosurgery. One rare complication is the formation of an abdominal pseudocyst, which can cause shunt malfunction. Case descriptions We present four unique cases of abdominal pseudocyst formation. Our first patient initially presented with a right upper quadrant pseudocyst. Shunt was externalized and the distal end was revised with placement of catheter on the opposite side. He developed another pseudocyst within 5 months of shunt revision and developed another shunt failure. Our second patient had a history of shunt revisions and a known pseudocyst, presented with small bowel obstruction, and underwent laparotomy for the lysis of adhesions with improvement in his symptoms. After multiple readmissions for the same problem, it was thought that the pseudocyst was causing gastric outlet obstruction and his VP shunt was converted into a ventriculopleural shunt followed by percutaneous drainage of his pseudocyst. Our third patient developed hydrocephalus secondary to cryptococcal meningitis. He developed abdominal pain secondary to an abdominal pseudocyst, which was drained percutaneously with relief of symptoms. The fourth patient had a history of multiple shunt revisions and a previous percutaneous pseudocyst drainage that recurred with cellulitis and abscess secondary to hardware infection. Conclusion Abdominal pseudocysts are a rare but important complication of VP shunt placement. Treatment depends on etiology, patient presentation, and clinical manifestations. Techniques for revision include distal repositioning of peritoneal catheter, revision of catheter into pleural space or right atrium, or removal of the shunt completely.

Infections in Deep Brain Stimulator Surgery.

Abstract: Introduction: Deep brain stimulation has emerged as an effective treatment for movement disorders such as Parkinson’s disease, dystonia, and essential tremor with estimates of >100,000 deep brain stimulators (DBSs) implanted worldwide since 1980s. Infections rates vary widely in the literature with rates as high as 25%. Traditional management of infection after deep brain stimulation is systemic antibiotic therapy with wound incision and debridement (I&D) and removal of implanted DBS hardware. The aim of this study is to evaluate the infections occurring after DBS placement and implantable generator (IPG) placement in order to better prevent and manage these infections. Materials/Methods: We conducted a retrospective review of 203 patients who underwent implantation of a DBS at a single institution. For initial electrode placement, patients underwent either unilateral or bilateral electrode placement with implantation of the IPG at the same surgery and IPG replacements occurred as necessary. For patients with unilateral electrodes, repeat surgery for placement of contralateral electrode was performed when desired. Preoperative preparation with ethyl alcohol occurred in all patients while use of intra-operative vancomycin powder was surgeon dependent. All patients received 24 hours of postoperative antibiotics. Primary endpoint was surgical wound infection or brain abscess located near the surgically implanted DBS leads. Infections were classified as early ( 90 days). Infectious organisms were recorded based on intra-operative wound cultures. Number of lead implantations, IPG replacements and choice of presurgical, intra-operative, and postsurgical antibiotics were recorded and outcomes compared. Results: Two hundred and three patients underwent 391 electrode insertions and 244 IPG replacements. Fourteen patients developed an infection (10 early versus 4 late); 12 after implantation surgery (3%) and 2 after IPG replacement surgery (0.8%). No intracranial abscesses were found. Most common sites were the chest and connector. Staphylococcus aureus (MSSA) was the most common organism. Intra-operative vancomycin powder did not decrease infection risk. Vancomycin powder use was shown to increase risk of infection after electrode implantation surgery (Relative Risk 5.5080, p = 0.02063). Complete hardware removal occurred in eight patients, one patient had electrode only removal, three patients with I&D and no removal of hardware, and two patients with removal of IPG and extensor cables only. All patients were treated with postoperative intravenous antibiotics and no recurrent infections were found in patients with hardware left in place. Discussion/Conclusion: Infections after DBS implantation and IPG replacement occurred in 3% and 0.8% of patients respectively in our study which is lower than reported historically. Early infections were more common. No intracranial infections were found. Intra-operative use of vancomycin was not shown to decrease risk of infection after electrode implantation surgery or IPG replacement. However, in our study it was shown to increase risk of infection after electrode implantation surgery. Treatment includes antibiotic therapy and debridement with or without removal of hardware. DBS hardware can be safely left in place in select patients who may have significant adverse effects if it is removed.

Comparison of Ventricular and Lumbar Cerebrospinal Fluid Composition.

Abstract: Objective Cerebrospinal fluid (CSF) analysis is a common diagnostic tool used to evaluate diseases of the central nervous system (CNS). We sought to determine whether there is a difference between the composition of CSF sampled from an external ventricular drain (EVD) and lumbar drain (LD) and whether this made a difference in guiding therapeutic decisions. Patients and Methods This study was a retrospective analysis from a single neurosurgery service between the dates of January 2011 and April 2019. A total of 12,134 patients were screened. Inclusion criteria were ages 18-80 and the presence of both an EVD and LD. Exclusion criteria were not having both routes of CSF sampling and the inability to determine which samples originated from which compartment. Results Six patients underwent simultaneous spinal and ventricular routine CSF sampling <24 hours apart and were analyzed for their compositions. There were 42 samples, but only 20 paired EVD-LD samples that could be analyzed. When comparing the EVD and LD sample compositions, there were statistically significant differences in white blood cells (WBCs; p = 0.040), total protein (p = 0.042), and glucose (p = 0.043). Red blood cells (RBCs; p = 0.104) and polymorphonuclear leukocytes (PMN; p = 0.544) were not statistically significant. We found a statistically significant correlation between cranial and spinal CSF WBC (r = 0.944, p < 0.001), protein (r = 0.679, p = 0.001), and glucose (r = 0.805, p < 0.001). We also found that there was a significant correlation between CSF and serum glucose (r = 0.502, p = 0.040). There was no statistically significant correlation between RBCs (r = 0.276, p = 0.252). Conclusion Our results demonstrate a correlation between the cranial and spinal CSF samples, except for RBCs, with statistically significant differences in WBC, glucose, and protein values between the two sites. This confirms that sampling CSF via lumbar puncture, which carries less risk than a ventriculostomy and provides accurate data to help establish a diagnosis for intracranial pathologies.

Prevalence of Catheter-Associated Urinary Tract Infections in Neurosurgical Intensive Care Patients – The Overdiagnosis of Urinary Tract Infections

Abstract: Background: Hospital-acquired infections (HAIs) are profound causes of prolonged hospital stay and worse patient outcomes. HAIs pose serious risks, particularly in neurosurgical patients in the intensive care unit, as these patients are seldom able to express symptoms of infection, with only elevated temperatures as the initial symptom. Data from Center for Disease Control (CDC) and the Infectious Disease Society of America (IDSA) have shown that of all HAIs, urinary tract infections (UTIs) have been grossly over-reported, resulting in excessive and unnecessary antibiotic usage. Methods: We conducted a retrospective analysis of 686 adult patients that were evaluated by the neurosurgery service at Arrowhead Regional Medical Center between July 2018 and March 2019. Inclusion criteria were adults greater than 18 years of age with neurosurgical pathology requiring a minimum of one full day admission to the intensive care unit (ICU), and an indwelling urinary catheter. Exclusion criteria were patients under the age of 18, those who did not spend any time in the ICU, or with renal pathologies such as renal failure. Results: We reviewed 686 patients from the neurosurgical census. In total, 146 adult patients with indwelling urinary catheters were selected into the statistical analysis. Most individuals spent an average of 8.91 ± 9.70 days in the ICU and had an indwelling catheter for approximately 8.14 ± 7.95 days. Forty-two out of the 146 individuals were found to have a temperature of 100.4°F or higher. Majority of the patients with an elevated temperature had an infectious source other than urine, such as sputum (22 out of 42, 52.38%), blood (three out of 42, 7.14%) or CSF (one out of 42, 2.38%). We were able to find only two individuals (4.76%) with a positive urine culture and no evidence of other positive cultures or deep vein thrombosis. Conclusions: Our analysis shows evidence to support the newest IDSA guidelines that patients with elevated temperatures should have a clinical workup of all alternative etiologies prior to testing for a urinary source unless the clinical suspicion is high. This will help reduce the rate of unnecessary urine cultures, the over-diagnosis of asymptomatic bacteriuria, and the overuse of antibiotics. Based on our current findings, all potential sources of fever should be ruled out prior to obtaining urinalysis, and catheters should be removed as soon as they are not needed. Urinalysis with reflex to urine culture should be reserved for those cases where there remains a high index of clinical suspicion for a urinary source.

Spontaneous Intracranial Hypotension: Case Study and Review of the Literature

Abstract: Spontaneous intracranial hypotension (SIH) is a pathology characterized by orthostatic headaches, diffuse pachymeningeal enhancement on magnetic resonance imaging (MRI), and low to normal cerebrospinal fluid (CSF) pressures. We present the case of a 46-year-old male with refractory postural headaches, found to have a diffuse CSF leak throughout the cervicothoracic (C1-T12) spine. His neurological status declined rapidly to a Glasgow Coma Scale (GCS) of eight, necessitating bilateral subdural drain placement. Despite an overall brisk neurologic recovery, the patient remained unable to speak for nearly a week after the return of the remainder of his function. This raised the concern for possible cerebellar mutism. We review the multiple modalities used in this patient's treatment and explore possible explanations for the failure of initial therapy. The placement of bilateral subdural drains was a temporizing measure to treat the patient's neurologic decline, but it was likely the epidural blood patch with prolonged bedrest that hastened the patient's recovery. His speech function also returned with time and repeated therapy.

Recent update on basic mechanisms of spinal cord injury

Abstract: Spinal cord injury (SCI) is a life-shattering neurological condition that affects between 250,000 and 500,000 individuals each year with an estimated two to three million people worldwide living with an SCI-related disability. The incidence in the USA and Canada is more than that in other countries with motor vehicle accidents being the most common cause, while violence being most common in the developing nations. Its incidence is two- to fivefold higher in males, with a peak in younger adults. Apart from the economic burden associated with medical care costs, SCI predominantly affects a younger adult population. Therefore, the psychological impact of adaptation of an average healthy individual as a paraplegic or quadriplegic with bladder, bowel, or sexual dysfunction in their early life can be devastating. People with SCI are two to five times more likely to die prematurely, with worse survival rates in low- and middle-income countries. This devastating disorder has a complex and multifaceted mechanism. Recently, a lot of research has been published on the restoration of locomotor activity and the therapeutic strategies. Therefore, it is imperative for the treating physicians to understand the complex underlying pathophysiological mechanisms of SCI.

Identifying the risk factors for catheter-associated urinary tract infections: a large cross-sectional study of six hospitals.

Abstract: Motivation Catheter-associated urinary tract infections (CAUTI) are a common and serious healthcare-associated infection. Despite many efforts to reduce the occurrence of CAUTI, there remains a gap in the literature about CAUTI risk factors, especially pertaining to the effect of catheter dwell-time on CAUTI development and patient comorbidities. Objective To examine how the risk for CAUTI changes over time. Additionally, to assess whether time from catheter insertion to CAUTI event varied according to risk factors such as age, sex, patient type (surgical vs medical) and comorbidities. Design Retrospective cohort study of all patients who were catheterised from 2012 to 2016, including those who did and did not develop CAUTIs. Both paediatric and adult patients were included. Indwelling urinary catheterisation is the exposure variable. The variable is interval, as all participants were exposed but for different lengths of time. Setting Urban academic health system of over 2500 beds. The system encompasses two large academic medical centres, two community hospitals and a paediatric hospital. Results The study population was 47 926 patients who had 61 047 catheterisations, of which 861 (1.41%) resulted in a CAUTI. CAUTI rates were found to increase non-linearly for each additional day of catheterisation; CAUTI-free survival was 97.3% (CI: 97.1 to 97.6) at 10 days, 88.2% (CI: 86.9 to 89.5) at 30 days and 71.8% (CI: 66.3 to 77.8) at 60 days. This translated to an instantaneous HR of. 49%–1.65% in the 10–60 day time range. Paraplegia, cerebrovascular disease and female sex were found to statistically increase the chances of a CAUTI. Conclusions Using a very large data set, we demonstrated the incremental risk of CAUTI associated with each additional day of catheterisation, as well as the risk factors that increase the hazard for CAUTI. Special attention should be given to patients carrying these risk factors, for example, females or those with mobility issues.

Manipulation and Mobilization for Treating Chronic Low Back Pain

Abstract: BACKGROUND CONTEXT Mobilization and manipulation therapies are widely used to benefit patients with chronic low back pain. However, questions remain about their efficacy, dosing, safety, and how these approaches compare with other therapies. PURPOSE The present study aims to determine the efficacy, effectiveness, and safety of various mobilization and manipulation therapies for treatment of chronic low back pain. STUDY DESIGN/SETTING This is a systematic literature review and meta-analysis. OUTCOME MEASURES The present study measures self-reported pain, function, health-related quality of life, and adverse events. METHODS We identified studies by searching multiple electronic databases from January 2000 to March 2017, examining reference lists, and communicating with experts. We selected randomized controlled trials comparing manipulation or mobilization therapies with sham, no treatment, other active therapies, and multimodal therapeutic approaches. We assessed risk of bias using Scottish Intercollegiate Guidelines Network criteria. Where possible, we pooled data using random-effects meta-analysis. Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) was applied to determine the confidence in effect estimates. This project is funded by the National Center for Complementary and Integrative Health under Award Number U19AT007912. RESULTS Fifty-one trials were included in the systematic review. Nine trials (1,176 patients) provided sufficient data and were judged similar enough to be pooled for meta-analysis. The standardized mean difference for a reduction of pain was SMD=−0.28, 95% confidence interval (CI) −0.47 to −0.09, p=.004; I2=57% after treatment; within seven trials (923 patients), the reduction in disability was SMD=−0.33, 95% CI −0.63 to −0.03, p=.03; I2=78% for manipulation or mobilization compared with other active therapies. Subgroup analyses showed that manipulation significantly reduced pain and disability, compared with other active comparators including exercise and physical therapy (SMD=−0.43, 95% CI −0.86 to 0.00; p=.05, I2=79%; SMD=−0.86, 95% CI −1.27 to −0.45; p<.0001, I2=46%). Mobilization interventions, compared with other active comparators including exercise regimens, significantly reduced pain (SMD=−0.20, 95% CI −0.35 to −0.04; p=.01; I2=0%) but not disability (SMD=−0.10, 95% CI −0.28 to 0.07; p=.25; I2=21%). Studies comparing manipulation or mobilization with sham or no treatment were too few or too heterogeneous to allow for pooling as were studies examining relationships between dose and outcomes. Few studies assessed health-related quality of life. Twenty-six of 51 trials were multimodal studies and narratively described. CONCLUSION There is moderate-quality evidence that manipulation and mobilization are likely to reduce pain and improve function for patients with chronic low back pain; manipulation appears to produce a larger effect than mobilization. Both therapies appear safe. Multimodal programs may be a promising option.

COVID-19 associated rhino-orbital-cerebral mucormycosis: An observational study from Eastern India, with special emphasis on neurological spectrum.

Abstract: Aims: 1 Describe the epidemiology and determine risk factors for COVID-19 associated mucormycosis. 2 Elaborate the clinical spectrum of Rhino-Orbital-Cerebral Mucormycosis (ROCM), pattern of neuroaxis involvement and it's radiological correlates. Methods Observational study. Consecutive, confirmed cases of mucormycosis (N = 55) were included. A case of mucormycosis was defined as one who had clinical and radiological features consistent with mucormycosis along with demonstration of the fungus in tissue via KOH mount/culture/histopathological examination (HPE). Data pertaining to epidemiology, risk factors, clinico-radiological features were analysed using percentage of total cases. Results Middle aged, diabetic males with recent COVID-19 infection were most affected. New onset upper jaw toothache was a striking observation in several cases. Among neurological manifestations headache, proptosis, vision loss, extraocular movement restriction; cavernous sinus, meningeal and parenchymal involvement were common. Stroke in ROCM followed a definitive pattern with watershed infarction. Conclusions New onset upper jaw toothache and loosening of teeth should prompt an immediate search for mucormycosis in backdrop of diabetic patients with recent COVID-19 disease, aiding earlier diagnosis and treatment initiation. Neuroaxis involvement was characterized by a multitude of features pertaining to involvement of optic nerve, extraocular muscles, meninges, brain parenchyma and internal carotid artery.

Imaging features of rhinocerebral mucormycosis: from onset to vascular complications.

Abstract: Rhinocerebral mucormycosis (RCM) may result in severe intracranial ischemic and hemorrhagic lesions. Both computed tomography (CT) and magnetic resonance imaging (MRI) play an essential role in the diagnosis of RCM, but whereas CT is better for assessing bone erosion, MRI is superior in evaluating soft tissue, intraorbital extension, and in assessing intracranial and vascular invasion. Specific CT and MRI techniques, such as CT angiography or enhanced MR angiography, and more advanced MRI sequences such as gadolinium-3D Black Blood imaging, contribute to the assessment of the extension of vascular invasion.In this pictorial review, we describe specific CT and MRI signs of RCM, mainly focusing on its life-threatening complications due to vascular involvement.