Kemel A. Ghotme, MD | Universidad de La Sabana (original) (raw)

Papers by Kemel A. Ghotme, MD

Research paper thumbnail of Timing of surgery following SARS-CoV-2 infection: an international prospective cohort study

Anaesthesia, 2021

Peri-operative SARS-CoV-2 infection increases postoperative mortality. The aim of this study was ... more Peri-operative SARS-CoV-2 infection increases postoperative mortality. The aim of this study was to determine the optimal duration of planned delay before surgery in patients who have had SARS-CoV-2 infection. This international, multicentre, prospective cohort study included patients undergoing elective or emergency surgery during October 2020. Surgical patients with pre-operative SARS-CoV-2 infection were compared with those without previous SARS-CoV-2 infection. The primary outcome measure was 30-day postoperative mortality. Logistic regression models were used to calculate adjusted 30-day mortality rates stratified by time from diagnosis of SARS-CoV-2 infection to surgery. Among 140,231 patients (116 countries), 3127 patients (2.2%) had a pre-operative SARS-CoV-2 diagnosis. Adjusted 30-day mortality in patients without SARS-CoV-2 infection was 1.5% (95%CI 1.4-1.5). In patients with a pre-operative SARS-CoV-2 diagnosis, mortality was increased in patients having surgery within 0-2 weeks, 3-4 weeks and 5-6 weeks of the diagnosis (odds ratio (95%CI) 4.1 (3.3-4.8), 3.9 (2.6-5.1) and 3.6 (2.0-5.2), respectively). Surgery performed ≥ 7 weeks after SARS-CoV-2 diagnosis was associated with a similar mortality risk to baseline (odds ratio (95%CI) 1.5 (0.9-2.1)). After a ≥ 7 week delay in undertaking surgery following SARS-CoV-2 infection, patients with ongoing symptoms had a higher mortality than patients whose symptoms had resolved or who had been asymptomatic (6.0% (95%CI 3.2-8.7) vs. 2.4% (95%CI 1.4-3.4) vs. 1.3% (95%CI 0.6-2.0), respectively). Where possible, surgery should be delayed for at least 7 weeks following SARS-CoV-2 infection. Patients with ongoing symptoms ≥ 7 weeks from diagnosis may benefit from further delay.

Research paper thumbnail of Accidentes ofídicos en Yopal y Leticia, Colombia, 1996-1997

Biomédica, 2002

El accidente ofídico presenta un elevado impacto sobre la morbimortalidad en la Amazonia y la Ori... more El accidente ofídico presenta un elevado impacto sobre la morbimortalidad en la Amazonia y la Orinoquia colombianas. En este estudio se revisaron prospectivamente los casos ocurridos en los hospitales de Leticia y Yopal durante el período comprendido entre septiembre de 1996 y junio de 1997. El 57% de los accidentes estudiados ocurrieron en Leticia. El 54% de los accidentes se presentaron en hombres y el grupo de edad más comprometido fue el de 15 a 44 años (41%). El 57% de los casos ocurrió a campo abierto y el pico de accidentalidad se presentó entre las 17 y las 18 horas. El 82% de las mordeduras fue en miembros inferiores. Se presentó un fallecimiento (1,8%) en Yopal y se practicaron 3 fasciotomías y 2 amputaciones; el 16% de los casos presentó infección secundaria. Las horas vespertinas presentan el mayor riesgo de accidente durante la jornada diaria. A pesar del uso generalizado de antibióticos, la infección secundaria fue frecuente en esta serie de casos.

Research paper thumbnail of Preventing birth defects, saving lives, and promoting health equity: an urgent call to action for universal mandatory food fortification with folic acid

Research paper thumbnail of Proposal for a normal pressure hydrocephalus syndrome center of excellence

Interdisciplinary Neurosurgery, 2022

Research paper thumbnail of Desenlace de craniectomía descompresiva primaria y secundaria en pacientes con trauma craneoencefálico severo en la Clínica Universidad de la Sabana

Salud Uninorte, 2022

Objetivos: El propósito de este estudio fue determinar el desenlace en el egreso y en el seguimie... more Objetivos: El propósito de este estudio fue determinar el desenlace en el egreso y en el seguimiento a un año de los pacientes con trauma craneoencefálico severo sometidos a craniectomía descompresiva primaria y secundaria en la Clínica de la Universidad de La Sabana, en un periodo de cinco años. Pacientes y métodos: Se llevó a cabo una serie de casos retrospectiva de pacientes con trauma craneoencefálico severo sometidos a craniectomía descompresiva entre 2008 y 2013. Los desenlaces primarios fueron la sobrevida y el estado funcional medido por la es cala de desenlace de Glasgow al momento del egreso hospitalario y al año de seguimiento. Como desenlaces secundarios se incluyeron el tiempo de latencia para la realización de la craniectomía, las complicaciones intra- y postoperatorias, días de hospitalización y estancia en la unidad de cuidados intensivos, tiempo de ventilación, resultados de la craneoplastia y causa de muerte. Resultados: Treinta y cinco pacientes con trauma craneoe...

Research paper thumbnail of Timing of surgery following SARS‐CoV‐2 infection: an international prospective cohort study

Anaesthesia, 2021

Peri-operative SARS-CoV-2 infection increases postoperative mortality. The aim of this study was ... more Peri-operative SARS-CoV-2 infection increases postoperative mortality. The aim of this study was to determine the optimal duration of planned delay before surgery in patients who have had SARS-CoV-2 infection. This international, multicentre, prospective cohort study included patients undergoing elective or emergency surgery during October 2020. Surgical patients with pre-operative SARS-CoV-2 infection were compared with those without previous SARS-CoV-2 infection. The primary outcome measure was 30-day postoperative mortality. Logistic regression models were used to calculate adjusted 30-day mortality rates stratified by time from diagnosis of SARS-CoV-2 infection to surgery. Among 140,231 patients (116 countries), 3127 patients (2.2%) had a pre-operative SARS-CoV-2 diagnosis. Adjusted 30-day mortality in patients without SARS-CoV-2 infection was 1.5% (95%CI 1.4-1.5). In patients with a pre-operative SARS-CoV-2 diagnosis, mortality was increased in patients having surgery within 0-2 weeks, 3-4 weeks and 5-6 weeks of the diagnosis (odds ratio (95%CI) 4.1% (3.3-4.8), 3.9% (2.6-5.1) and 3.6% (2.0-5.2), respectively). Surgery performed ≥ 7 weeks after SARS-CoV-2 diagnosis was associated with a similar mortality risk to baseline (odds ratio (95%CI) 1.5% (0.9-2.1%)). After a ≥ 7 week delay in undertaking surgery following SARS-CoV-2 infection, patients with ongoing symptoms had a higher mortality than patients whose symptoms had resolved or who had been asymptomatic (6.0% (95%CI 3.2-8.7) vs. 2.4% (95%CI 1.4-3.4) vs. 1.3% (95%CI 0.6-2.0%), respectively). Where possible, surgery should be delayed for at least 7 weeks following SARS-CoV-2 infection. Patients with ongoing symptoms ≥ 7 weeks from diagnosis may benefit from further delay.

Research paper thumbnail of Spontaneous thrombosis of a vein of Galen malformation associated with acute sinusitis: a case report

Child's Nervous System, 2021

The vein of Galen malformation is caused by an abnormal shunting between choroidal arteries and t... more The vein of Galen malformation is caused by an abnormal shunting between choroidal arteries and the median prosencephalic vein during embryological development, leading to increased blood flow to the deep cerebral veins, intracranial damage, and systemic repercussions. Idiopathic spontaneous thrombosis of a vein of Galen malformation is rare, and its association with acute sinusitis has not been reported in the literature. We present the case of a girl with a postnatal diagnosis of a vein of Galen malformation at the age of 16 months, with secondary pulmonary hypertension that was adequately controlled with spironolactone. At 3 years old, while expecting elective endovascular treatment, the patient developed spontaneous thrombosis of the vein of Galen malformation, concomitant to an acute sinusitis episode, with complete resolution of the vascular malformation and secondary pulmonary hypertension. The patient continued with normal neurological development over a 5-year follow-up. We discuss the main pathophysiologic mechanisms that can explain spontaneous thrombosis of VOGMs and the patient’s outcome. Awareness of different mechanisms that can lead to spontaneous thrombosis can help in the decision-making process and prompt targeted approaches to individual patients with a vein of Galen malformation.

Research paper thumbnail of Spinal cord issues in adult patients with MPS: transition of care survey

Child's Nervous System, 2018

PurposeThis study aims to raise awareness of the need for research and appropriate guidelines for... more PurposeThis study aims to raise awareness of the need for research and appropriate guidelines for managing spinal cord issues in adult patients with mucopolysaccharidosis (MPS) and transition of these patients from pediatric to adult care.MethodsPediatric/adult neurosurgeons, orthopedic spine surgeons, and treating physicians with expertise in metabolic disorders and spinal cord issues were invited to complete a survey to assess their experience with spinal cord problems in MPS and their opinion on transitioning routes from pediatric to adult care.ResultsTwenty specialists completed the survey; 16 had treated spinal cord issues in patients with MPS. Foramen magnum and cervical stenosis (87%), atlanto-axial instability (67%), and lumbar spine instability (33%) were the main spinal cord issues encountered; 28% had treated adult patients for one or more spinal cord issues. In 40% of cases, this concerned an intervention or procedures performed during childhood. The main specialist responsible for the care of adult patients with MPS differed considerably between institutions and included both pediatric and adult specialists (30% pediatric neurosurgeons, 10% pediatric spine orthopedic surgeons, 30% adult spine neurosurgeons, 20% general adult surgeons). The preferred option (> 50%) for the transition of care was an interdisciplinary team of pediatric and adult specialists.ConclusionsFurther work needs to be done to address problems of managing spinal cord issues in adult patients with MPS. Currently, the responsibility for the care of patients with MPS with spinal cord issues is inconsistent. The best strategy for transitioning these patients from pediatric to adult care is likely an interdisciplinary approach.

Research paper thumbnail of Abstracts from Hydrocephalus 2016

Fluids and barriers of the CNS, Jan 7, 2017

Introduction: Among the confirmed cases of hydrocephalus in the Middle East, there is no standard... more Introduction: Among the confirmed cases of hydrocephalus in the Middle East, there is no standardization of care or differentiation between various types of hydrocephalus. This is the first study in the Middle Eastern regions that aims at developing a hydrocephalus clinical protocol for appropriate standard of care. Methods: We used a well-established clinical protocol from Johns Hopkins University and adapted it to a locally relevant clinical context with the help of an interdisciplinary panel of experts. The final protocol included diagnostic radiology studies, lumbar punctures (LP) as indication for surgery in hydrocephalus patients, and standardized times for follow-up visits were scheduled for optimal management of care. Baseline and follow-up testing protocol included gait assessment scales [Tinetti Gait and Balance Scale, Timed Up and Go task (TUG)] and ICIQ Urinary Incontinence short form. Results: Key highlights were cultural and language barriers which resulted in editing the testing and measures for use within the region (ex. translation into Arabic, religious beliefs, and education levels were incorporated to modify protocols). Gender roles and space constraints restricted feasibility of gait testing and required invasive procedures (ex. TUG times could not be assessed in a public hallway for women and women demanded inpatient stays for LP). Conclusions: The study highlights the need to raise awareness and standardize clinical protocols for screening and treating NPH in the region. A critical analysis of issues related to the how and why of implementation, and in turn optimizing the appropriateness and relevance to the particular circumstances is essential.

Research paper thumbnail of SARS-CoV-2 vaccination modelling for safe surgery to save lives: data from an international prospective cohort study

British Journal of Surgery, 2021

Background Preoperative SARS-CoV-2 vaccination could support safer elective surgery. Vaccine numb... more Background Preoperative SARS-CoV-2 vaccination could support safer elective surgery. Vaccine numbers are limited so this study aimed to inform their prioritization by modelling. Methods The primary outcome was the number needed to vaccinate (NNV) to prevent one COVID-19-related death in 1 year. NNVs were based on postoperative SARS-CoV-2 rates and mortality in an international cohort study (surgical patients), and community SARS-CoV-2 incidence and case fatality data (general population). NNV estimates were stratified by age (18–49, 50–69, 70 or more years) and type of surgery. Best- and worst-case scenarios were used to describe uncertainty. Results NNVs were more favourable in surgical patients than the general population. The most favourable NNVs were in patients aged 70 years or more needing cancer surgery (351; best case 196, worst case 816) or non-cancer surgery (733; best case 407, worst case 1664). Both exceeded the NNV in the general population (1840; best case 1196, worst ...

Research paper thumbnail of Use of transcranial magnetic stimulation for studying the neural basis of numerical cognition: A systematic review

Journal of Neuroscience Methods

Research paper thumbnail of Gliomas: New Perspectives in Diagnosis, Treatment and Prognosis

Gliomas are central nervous system tumors originated from glial cells, whose incidence and mortal... more Gliomas are central nervous system tumors originated from glial cells, whose incidence and mortality is expected to rise in coming years, especially in developing countries. Diagnosis and classification of gliomas have largely relied on tumor histopathologic features that provide limited information regarding response to therapy or prognosis. Current treatment of gliomas is surgery combined with chemotherapy and/or radiotherapy. However, many tumors show a high resistance to these interventions, and recurrences are frequent since conventional therapies do not take into account the unique molecular features of different subtypes of glioma. Molecular genetics provide new insights in classifying gliomas and predicting response to therapy that can range from conventional treatments to new revolutionary therapeutic approaches. This article offers a review of the intracellular signaling pathways involved in carcinogenesis of gliomas, as well as a description of new tools for their diagnos...

Research paper thumbnail of Evaluación del proceso de gestión educativa para la integración de modelos didácticos mediados por TIC: un estudio de caso múltiple

Ensaio: Avaliação e Políticas Públicas em Educação

Resumen El artículo presenta un estudio orientado a evaluar el efecto de la implementación de los... more Resumen El artículo presenta un estudio orientado a evaluar el efecto de la implementación de los modelos didácticos mediados por TIC, en las prácticas de Enseñanza en algunos contextos educativos colombianos, desde una investigación mixta enmarcada en los diseños de evaluación a partir de las teorías de Guskey para evaluar el efecto del fenómeno estudiado combinado con el diseño de investigación basado en el estudio caso múltiple que permite explicar el aporte de estos modelos en el aprendizaje. Se trabajó con 35 maestros colombianos de escuelas y universidades ubicadas en zonas geográficas rurales y urbanas, caracterizadas por pertenecer a escenarios con limitaciones económicas y realidades sociales marcadas por el conflicto. En las conclusiones fue posible corroborar la hipótesis alternativa (Ha) que declara que la gestión de proyectos de innovación educativa favorece parcialmente la cualificación de las prácticas de Enseñanza; esto, como producto de variables extrañas sobre la b...

Research paper thumbnail of Central and peripheral nervous system involvement by COVID-19: a systematic review of the pathophysiology, clinical manifestations, neuropathology, neuroimaging, electrophysiology, and cerebrospinal fluid findings

BMC Infectious Diseases

Background SARS-CoV-2 can affect the human brain and other neurological structures. An increasing... more Background SARS-CoV-2 can affect the human brain and other neurological structures. An increasing number of publications report neurological manifestations in patients with COVID-19. However, no studies have comprehensively reviewed the clinical and paraclinical characteristics of the central and peripheral nervous system’s involvement in these patients. This study aimed to describe the features of the central and peripheral nervous system involvement by COVID-19 in terms of pathophysiology, clinical manifestations, neuropathology, neuroimaging, electrophysiology, and cerebrospinal fluid findings. Methods We conducted a comprehensive systematic review of all the original studies reporting patients with neurological involvement by COVID-19, from December 2019 to June 2020, without language restriction. We excluded studies with animal subjects, studies not related to the nervous system, and opinion articles. Data analysis combined descriptive measures, frequency measures, central tend...

Research paper thumbnail of SARS-CoV-2 vaccination modelling for safe surgery to save lives: data from an international prospective cohort study

British Journal of Surgery, 2021

Background: Preoperative SARS-CoV-2 vaccination could support safer elective surgery. Vaccine num... more Background: Preoperative SARS-CoV-2 vaccination could support safer elective surgery. Vaccine numbers are limited so this study aimed to inform their prioritization by modelling. Methods: The primary outcome was the number needed to vaccinate (NNV) to prevent one COVID-19-related death in 1 year. NNVs were based on postoperative SARS-CoV-2 rates and mortality in an international cohort study (surgical patients), and community SARS-CoV-2 incidence and case fatality data (general population). NNV estimates were stratified by age (18-49, 50-69, 70 or more years) and type of surgery. Best-and worst-case scenarios were used to describe uncertainty. Results: NNVs were more favourable in surgical patients than the general population. The most favourable NNVs were in patients aged 70 years or more needing cancer surgery (351; best case 196, worst case 816) or non-cancer surgery (733; best case 407, worst case 1664). Both exceeded the NNV in the general population (1840; best case 1196, worst case 3066). NNVs for surgical patients remained favourable at a range of SARS-CoV-2 incidence rates in sensitivity analysis modelling. Globally, prioritizing preoperative vaccination of patients needing elective surgery ahead of the general population could prevent an additional 58 687 (best case 115 007, worst case 20 177) COVID-19-related deaths in 1 year. Conclusion: As global roll out of SARS-CoV-2 vaccination proceeds, patients needing elective surgery should be prioritized ahead of the general population.

Research paper thumbnail of Spontaneous thrombosis of a vein of Galen malformation associated with acute sinusitis: a case report

Child's Nervous System, 2021

The vein of Galen malformation is caused by an abnormal shunting between choroidal arteries and t... more The vein of Galen malformation is caused by an abnormal shunting between choroidal arteries and the median prosencephalic vein during embryological development, leading to increased blood flow to the deep cerebral veins, intracranial damage, and systemic repercussions. Idiopathic spontaneous thrombosis of a vein of Galen malformation is rare, and its association with acute sinusitis has not been reported in the literature. We present the case of a girl with a postnatal diagnosis of a vein of Galen malformation at the age of 16 months, with secondary pulmonary hypertension that was adequately controlled with spironolactone. At 3 years old, while expecting elective endovascular treatment, the patient developed spontaneous thrombosis of the vein of Galen malformation, concomitant to an acute sinusitis episode, with complete resolution of the vascular malformation and secondary pulmonary hypertension. The patient continued with normal neurological development over a 5-year follow-up. We discuss the main pathophysiologic mechanisms that can explain spontaneous thrombosis of VOGMs and the patient's outcome. Awareness of different mechanisms that can lead to spontaneous thrombosis can help in the decision-making process and prompt targeted approaches to individual patients with a vein of Galen malformation.

Research paper thumbnail of SARS-CoV-2 vaccination modelling for safe surgery to save lives: data from an international prospective cohort study

British Journal of Surgery, 2021

Background: Preoperative SARS-CoV-2 vaccination could support safer elective surgery. Vaccine num... more Background: Preoperative SARS-CoV-2 vaccination could support safer elective surgery. Vaccine numbers are limited so this study aimed to inform their prioritization by modelling. Methods: The primary outcome was the number needed to vaccinate (NNV) to prevent one COVID-19-related death in 1 year. NNVs were based on postoperative SARS-CoV-2 rates and mortality in an international cohort study (surgical patients), and community SARS-CoV-2 incidence and case fatality data (general population). NNV estimates were stratified by age (18-49, 50-69, 70 or more years) and type of surgery. Best-and worst-case scenarios were used to describe uncertainty. Results: NNVs were more favourable in surgical patients than the general population. The most favourable NNVs were in patients aged 70 years or more needing cancer surgery (351; best case 196, worst case 816) or non-cancer surgery (733; best case 407, worst case 1664). Both exceeded the NNV in the general population (1840; best case 1196, worst case 3066). NNVs for surgical patients remained favourable at a range of SARS-CoV-2 incidence rates in sensitivity analysis modelling. Globally, prioritizing preoperative vaccination of patients needing elective surgery ahead of the general population could prevent an additional 58 687 (best case 115 007, worst case 20 177) COVID-19-related deaths in 1 year. Conclusion: As global roll out of SARS-CoV-2 vaccination proceeds, patients needing elective surgery should be prioritized ahead of the general population.

Research paper thumbnail of Timing of surgery following SARS-CoV-2 infection: an international prospective cohort study

Anaesthesia, 2021

Peri-operative SARS-CoV-2 infection increases postoperative mortality. The aim of this study was ... more Peri-operative SARS-CoV-2 infection increases postoperative mortality. The aim of this study was to determine the optimal duration of planned delay before surgery in patients who have had SARS-CoV-2 infection. This international, multicentre, prospective cohort study included patients undergoing elective or emergency surgery during October 2020. Surgical patients with pre-operative SARS-CoV-2 infection were compared with those without previous SARS-CoV-2 infection. The primary outcome measure was 30-day postoperative mortality. Logistic regression models were used to calculate adjusted 30-day mortality rates stratified by time from diagnosis of SARS-CoV-2 infection to surgery. Among 140,231 patients (116 countries), 3127 patients (2.2%) had a pre-operative SARS-CoV-2 diagnosis. Adjusted 30-day mortality in patients without SARS-CoV-2 infection was 1.5% (95%CI 1.4-1.5). In patients with a pre-operative SARS-CoV-2 diagnosis, mortality was increased in patients having surgery within 0-2 weeks, 3-4 weeks and 5-6 weeks of the diagnosis (odds ratio (95%CI) 4.1 (3.3-4.8), 3.9 (2.6-5.1) and 3.6 (2.0-5.2), respectively). Surgery performed ≥ 7 weeks after SARS-CoV-2 diagnosis was associated with a similar mortality risk to baseline (odds ratio (95%CI) 1.5 (0.9-2.1)). After a ≥ 7 week delay in undertaking surgery following SARS-CoV-2 infection, patients with ongoing symptoms had a higher mortality than patients whose symptoms had resolved or who had been asymptomatic (6.0% (95%CI 3.2-8.7) vs. 2.4% (95%CI 1.4-3.4) vs. 1.3% (95%CI 0.6-2.0), respectively). Where possible, surgery should be delayed for at least 7 weeks following SARS-CoV-2 infection. Patients with ongoing symptoms ≥ 7 weeks from diagnosis may benefit from further delay.

Research paper thumbnail of Cell therapy for spinal cord injury with olfactory ensheathing glia cells (OECs)

Glia, Jul 13, 2018

The prospects of achieving regeneration in the central nervous system (CNS) have changed, as most... more The prospects of achieving regeneration in the central nervous system (CNS) have changed, as most recent findings indicate that several species, including humans, can produce neurons in adulthood. Studies targeting this property may be considered as potential therapeutic strategies to respond to injury or the effects of demyelinating diseases in the CNS. While CNS trauma may interrupt the axonal tracts that connect neurons with their targets, some neurons remain alive, as seen in optic nerve and spinal cord (SC) injuries (SCIs). The devastating consequences of SCIs are due to the immediate and significant disruption of the ascending and descending spinal pathways, which result in varying degrees of motor and sensory impairment. Recent therapeutic studies for SCI have focused on cell transplantation in animal models, using cells capable of inducing axon regeneration like Schwann cells (SchCs), astrocytes, genetically modified fibroblasts and olfactory ensheathing glia cells (OECs). N...

Research paper thumbnail of Gliomas: New Perspectives in Diagnosis, Treatment and Prognosis

Current topics in medicinal chemistry, Jan 3, 2017

Gliomas are central nervous system tumors originated from glial cells, whose incidence and mortal... more Gliomas are central nervous system tumors originated from glial cells, whose incidence and mortality is expected to rise in coming years, especially in developing countries. Diagnosis and classification of gliomas have largely relied on tumor histopathologic features that provide limited information regarding response to therapy or prognosis. Current treatment of gliomas is surgery combined with chemotherapy and/or radiotherapy. However, many tumors show a high resistance to these interventions, and recurrences are frequent since conventional therapies do not take into account the unique molecular features of different subtypes of glioma. Molecular genetics provide new insights in classifying gliomas and predicting response to therapy that can range from conventional treatments to new revolutionary therapeutic approaches. This article offers a review of the intracellular signaling pathways involved in carcinogenesis of gliomas, as well as a description of new tools for their diagnos...

Research paper thumbnail of Timing of surgery following SARS-CoV-2 infection: an international prospective cohort study

Anaesthesia, 2021

Peri-operative SARS-CoV-2 infection increases postoperative mortality. The aim of this study was ... more Peri-operative SARS-CoV-2 infection increases postoperative mortality. The aim of this study was to determine the optimal duration of planned delay before surgery in patients who have had SARS-CoV-2 infection. This international, multicentre, prospective cohort study included patients undergoing elective or emergency surgery during October 2020. Surgical patients with pre-operative SARS-CoV-2 infection were compared with those without previous SARS-CoV-2 infection. The primary outcome measure was 30-day postoperative mortality. Logistic regression models were used to calculate adjusted 30-day mortality rates stratified by time from diagnosis of SARS-CoV-2 infection to surgery. Among 140,231 patients (116 countries), 3127 patients (2.2%) had a pre-operative SARS-CoV-2 diagnosis. Adjusted 30-day mortality in patients without SARS-CoV-2 infection was 1.5% (95%CI 1.4-1.5). In patients with a pre-operative SARS-CoV-2 diagnosis, mortality was increased in patients having surgery within 0-2 weeks, 3-4 weeks and 5-6 weeks of the diagnosis (odds ratio (95%CI) 4.1 (3.3-4.8), 3.9 (2.6-5.1) and 3.6 (2.0-5.2), respectively). Surgery performed ≥ 7 weeks after SARS-CoV-2 diagnosis was associated with a similar mortality risk to baseline (odds ratio (95%CI) 1.5 (0.9-2.1)). After a ≥ 7 week delay in undertaking surgery following SARS-CoV-2 infection, patients with ongoing symptoms had a higher mortality than patients whose symptoms had resolved or who had been asymptomatic (6.0% (95%CI 3.2-8.7) vs. 2.4% (95%CI 1.4-3.4) vs. 1.3% (95%CI 0.6-2.0), respectively). Where possible, surgery should be delayed for at least 7 weeks following SARS-CoV-2 infection. Patients with ongoing symptoms ≥ 7 weeks from diagnosis may benefit from further delay.

Research paper thumbnail of Accidentes ofídicos en Yopal y Leticia, Colombia, 1996-1997

Biomédica, 2002

El accidente ofídico presenta un elevado impacto sobre la morbimortalidad en la Amazonia y la Ori... more El accidente ofídico presenta un elevado impacto sobre la morbimortalidad en la Amazonia y la Orinoquia colombianas. En este estudio se revisaron prospectivamente los casos ocurridos en los hospitales de Leticia y Yopal durante el período comprendido entre septiembre de 1996 y junio de 1997. El 57% de los accidentes estudiados ocurrieron en Leticia. El 54% de los accidentes se presentaron en hombres y el grupo de edad más comprometido fue el de 15 a 44 años (41%). El 57% de los casos ocurrió a campo abierto y el pico de accidentalidad se presentó entre las 17 y las 18 horas. El 82% de las mordeduras fue en miembros inferiores. Se presentó un fallecimiento (1,8%) en Yopal y se practicaron 3 fasciotomías y 2 amputaciones; el 16% de los casos presentó infección secundaria. Las horas vespertinas presentan el mayor riesgo de accidente durante la jornada diaria. A pesar del uso generalizado de antibióticos, la infección secundaria fue frecuente en esta serie de casos.

Research paper thumbnail of Preventing birth defects, saving lives, and promoting health equity: an urgent call to action for universal mandatory food fortification with folic acid

Research paper thumbnail of Proposal for a normal pressure hydrocephalus syndrome center of excellence

Interdisciplinary Neurosurgery, 2022

Research paper thumbnail of Desenlace de craniectomía descompresiva primaria y secundaria en pacientes con trauma craneoencefálico severo en la Clínica Universidad de la Sabana

Salud Uninorte, 2022

Objetivos: El propósito de este estudio fue determinar el desenlace en el egreso y en el seguimie... more Objetivos: El propósito de este estudio fue determinar el desenlace en el egreso y en el seguimiento a un año de los pacientes con trauma craneoencefálico severo sometidos a craniectomía descompresiva primaria y secundaria en la Clínica de la Universidad de La Sabana, en un periodo de cinco años. Pacientes y métodos: Se llevó a cabo una serie de casos retrospectiva de pacientes con trauma craneoencefálico severo sometidos a craniectomía descompresiva entre 2008 y 2013. Los desenlaces primarios fueron la sobrevida y el estado funcional medido por la es cala de desenlace de Glasgow al momento del egreso hospitalario y al año de seguimiento. Como desenlaces secundarios se incluyeron el tiempo de latencia para la realización de la craniectomía, las complicaciones intra- y postoperatorias, días de hospitalización y estancia en la unidad de cuidados intensivos, tiempo de ventilación, resultados de la craneoplastia y causa de muerte. Resultados: Treinta y cinco pacientes con trauma craneoe...

Research paper thumbnail of Timing of surgery following SARS‐CoV‐2 infection: an international prospective cohort study

Anaesthesia, 2021

Peri-operative SARS-CoV-2 infection increases postoperative mortality. The aim of this study was ... more Peri-operative SARS-CoV-2 infection increases postoperative mortality. The aim of this study was to determine the optimal duration of planned delay before surgery in patients who have had SARS-CoV-2 infection. This international, multicentre, prospective cohort study included patients undergoing elective or emergency surgery during October 2020. Surgical patients with pre-operative SARS-CoV-2 infection were compared with those without previous SARS-CoV-2 infection. The primary outcome measure was 30-day postoperative mortality. Logistic regression models were used to calculate adjusted 30-day mortality rates stratified by time from diagnosis of SARS-CoV-2 infection to surgery. Among 140,231 patients (116 countries), 3127 patients (2.2%) had a pre-operative SARS-CoV-2 diagnosis. Adjusted 30-day mortality in patients without SARS-CoV-2 infection was 1.5% (95%CI 1.4-1.5). In patients with a pre-operative SARS-CoV-2 diagnosis, mortality was increased in patients having surgery within 0-2 weeks, 3-4 weeks and 5-6 weeks of the diagnosis (odds ratio (95%CI) 4.1% (3.3-4.8), 3.9% (2.6-5.1) and 3.6% (2.0-5.2), respectively). Surgery performed ≥ 7 weeks after SARS-CoV-2 diagnosis was associated with a similar mortality risk to baseline (odds ratio (95%CI) 1.5% (0.9-2.1%)). After a ≥ 7 week delay in undertaking surgery following SARS-CoV-2 infection, patients with ongoing symptoms had a higher mortality than patients whose symptoms had resolved or who had been asymptomatic (6.0% (95%CI 3.2-8.7) vs. 2.4% (95%CI 1.4-3.4) vs. 1.3% (95%CI 0.6-2.0%), respectively). Where possible, surgery should be delayed for at least 7 weeks following SARS-CoV-2 infection. Patients with ongoing symptoms ≥ 7 weeks from diagnosis may benefit from further delay.

Research paper thumbnail of Spontaneous thrombosis of a vein of Galen malformation associated with acute sinusitis: a case report

Child's Nervous System, 2021

The vein of Galen malformation is caused by an abnormal shunting between choroidal arteries and t... more The vein of Galen malformation is caused by an abnormal shunting between choroidal arteries and the median prosencephalic vein during embryological development, leading to increased blood flow to the deep cerebral veins, intracranial damage, and systemic repercussions. Idiopathic spontaneous thrombosis of a vein of Galen malformation is rare, and its association with acute sinusitis has not been reported in the literature. We present the case of a girl with a postnatal diagnosis of a vein of Galen malformation at the age of 16 months, with secondary pulmonary hypertension that was adequately controlled with spironolactone. At 3 years old, while expecting elective endovascular treatment, the patient developed spontaneous thrombosis of the vein of Galen malformation, concomitant to an acute sinusitis episode, with complete resolution of the vascular malformation and secondary pulmonary hypertension. The patient continued with normal neurological development over a 5-year follow-up. We discuss the main pathophysiologic mechanisms that can explain spontaneous thrombosis of VOGMs and the patient’s outcome. Awareness of different mechanisms that can lead to spontaneous thrombosis can help in the decision-making process and prompt targeted approaches to individual patients with a vein of Galen malformation.

Research paper thumbnail of Spinal cord issues in adult patients with MPS: transition of care survey

Child's Nervous System, 2018

PurposeThis study aims to raise awareness of the need for research and appropriate guidelines for... more PurposeThis study aims to raise awareness of the need for research and appropriate guidelines for managing spinal cord issues in adult patients with mucopolysaccharidosis (MPS) and transition of these patients from pediatric to adult care.MethodsPediatric/adult neurosurgeons, orthopedic spine surgeons, and treating physicians with expertise in metabolic disorders and spinal cord issues were invited to complete a survey to assess their experience with spinal cord problems in MPS and their opinion on transitioning routes from pediatric to adult care.ResultsTwenty specialists completed the survey; 16 had treated spinal cord issues in patients with MPS. Foramen magnum and cervical stenosis (87%), atlanto-axial instability (67%), and lumbar spine instability (33%) were the main spinal cord issues encountered; 28% had treated adult patients for one or more spinal cord issues. In 40% of cases, this concerned an intervention or procedures performed during childhood. The main specialist responsible for the care of adult patients with MPS differed considerably between institutions and included both pediatric and adult specialists (30% pediatric neurosurgeons, 10% pediatric spine orthopedic surgeons, 30% adult spine neurosurgeons, 20% general adult surgeons). The preferred option (> 50%) for the transition of care was an interdisciplinary team of pediatric and adult specialists.ConclusionsFurther work needs to be done to address problems of managing spinal cord issues in adult patients with MPS. Currently, the responsibility for the care of patients with MPS with spinal cord issues is inconsistent. The best strategy for transitioning these patients from pediatric to adult care is likely an interdisciplinary approach.

Research paper thumbnail of Abstracts from Hydrocephalus 2016

Fluids and barriers of the CNS, Jan 7, 2017

Introduction: Among the confirmed cases of hydrocephalus in the Middle East, there is no standard... more Introduction: Among the confirmed cases of hydrocephalus in the Middle East, there is no standardization of care or differentiation between various types of hydrocephalus. This is the first study in the Middle Eastern regions that aims at developing a hydrocephalus clinical protocol for appropriate standard of care. Methods: We used a well-established clinical protocol from Johns Hopkins University and adapted it to a locally relevant clinical context with the help of an interdisciplinary panel of experts. The final protocol included diagnostic radiology studies, lumbar punctures (LP) as indication for surgery in hydrocephalus patients, and standardized times for follow-up visits were scheduled for optimal management of care. Baseline and follow-up testing protocol included gait assessment scales [Tinetti Gait and Balance Scale, Timed Up and Go task (TUG)] and ICIQ Urinary Incontinence short form. Results: Key highlights were cultural and language barriers which resulted in editing the testing and measures for use within the region (ex. translation into Arabic, religious beliefs, and education levels were incorporated to modify protocols). Gender roles and space constraints restricted feasibility of gait testing and required invasive procedures (ex. TUG times could not be assessed in a public hallway for women and women demanded inpatient stays for LP). Conclusions: The study highlights the need to raise awareness and standardize clinical protocols for screening and treating NPH in the region. A critical analysis of issues related to the how and why of implementation, and in turn optimizing the appropriateness and relevance to the particular circumstances is essential.

Research paper thumbnail of SARS-CoV-2 vaccination modelling for safe surgery to save lives: data from an international prospective cohort study

British Journal of Surgery, 2021

Background Preoperative SARS-CoV-2 vaccination could support safer elective surgery. Vaccine numb... more Background Preoperative SARS-CoV-2 vaccination could support safer elective surgery. Vaccine numbers are limited so this study aimed to inform their prioritization by modelling. Methods The primary outcome was the number needed to vaccinate (NNV) to prevent one COVID-19-related death in 1 year. NNVs were based on postoperative SARS-CoV-2 rates and mortality in an international cohort study (surgical patients), and community SARS-CoV-2 incidence and case fatality data (general population). NNV estimates were stratified by age (18–49, 50–69, 70 or more years) and type of surgery. Best- and worst-case scenarios were used to describe uncertainty. Results NNVs were more favourable in surgical patients than the general population. The most favourable NNVs were in patients aged 70 years or more needing cancer surgery (351; best case 196, worst case 816) or non-cancer surgery (733; best case 407, worst case 1664). Both exceeded the NNV in the general population (1840; best case 1196, worst ...

Research paper thumbnail of Use of transcranial magnetic stimulation for studying the neural basis of numerical cognition: A systematic review

Journal of Neuroscience Methods

Research paper thumbnail of Gliomas: New Perspectives in Diagnosis, Treatment and Prognosis

Gliomas are central nervous system tumors originated from glial cells, whose incidence and mortal... more Gliomas are central nervous system tumors originated from glial cells, whose incidence and mortality is expected to rise in coming years, especially in developing countries. Diagnosis and classification of gliomas have largely relied on tumor histopathologic features that provide limited information regarding response to therapy or prognosis. Current treatment of gliomas is surgery combined with chemotherapy and/or radiotherapy. However, many tumors show a high resistance to these interventions, and recurrences are frequent since conventional therapies do not take into account the unique molecular features of different subtypes of glioma. Molecular genetics provide new insights in classifying gliomas and predicting response to therapy that can range from conventional treatments to new revolutionary therapeutic approaches. This article offers a review of the intracellular signaling pathways involved in carcinogenesis of gliomas, as well as a description of new tools for their diagnos...

Research paper thumbnail of Evaluación del proceso de gestión educativa para la integración de modelos didácticos mediados por TIC: un estudio de caso múltiple

Ensaio: Avaliação e Políticas Públicas em Educação

Resumen El artículo presenta un estudio orientado a evaluar el efecto de la implementación de los... more Resumen El artículo presenta un estudio orientado a evaluar el efecto de la implementación de los modelos didácticos mediados por TIC, en las prácticas de Enseñanza en algunos contextos educativos colombianos, desde una investigación mixta enmarcada en los diseños de evaluación a partir de las teorías de Guskey para evaluar el efecto del fenómeno estudiado combinado con el diseño de investigación basado en el estudio caso múltiple que permite explicar el aporte de estos modelos en el aprendizaje. Se trabajó con 35 maestros colombianos de escuelas y universidades ubicadas en zonas geográficas rurales y urbanas, caracterizadas por pertenecer a escenarios con limitaciones económicas y realidades sociales marcadas por el conflicto. En las conclusiones fue posible corroborar la hipótesis alternativa (Ha) que declara que la gestión de proyectos de innovación educativa favorece parcialmente la cualificación de las prácticas de Enseñanza; esto, como producto de variables extrañas sobre la b...

Research paper thumbnail of Central and peripheral nervous system involvement by COVID-19: a systematic review of the pathophysiology, clinical manifestations, neuropathology, neuroimaging, electrophysiology, and cerebrospinal fluid findings

BMC Infectious Diseases

Background SARS-CoV-2 can affect the human brain and other neurological structures. An increasing... more Background SARS-CoV-2 can affect the human brain and other neurological structures. An increasing number of publications report neurological manifestations in patients with COVID-19. However, no studies have comprehensively reviewed the clinical and paraclinical characteristics of the central and peripheral nervous system’s involvement in these patients. This study aimed to describe the features of the central and peripheral nervous system involvement by COVID-19 in terms of pathophysiology, clinical manifestations, neuropathology, neuroimaging, electrophysiology, and cerebrospinal fluid findings. Methods We conducted a comprehensive systematic review of all the original studies reporting patients with neurological involvement by COVID-19, from December 2019 to June 2020, without language restriction. We excluded studies with animal subjects, studies not related to the nervous system, and opinion articles. Data analysis combined descriptive measures, frequency measures, central tend...

Research paper thumbnail of SARS-CoV-2 vaccination modelling for safe surgery to save lives: data from an international prospective cohort study

British Journal of Surgery, 2021

Background: Preoperative SARS-CoV-2 vaccination could support safer elective surgery. Vaccine num... more Background: Preoperative SARS-CoV-2 vaccination could support safer elective surgery. Vaccine numbers are limited so this study aimed to inform their prioritization by modelling. Methods: The primary outcome was the number needed to vaccinate (NNV) to prevent one COVID-19-related death in 1 year. NNVs were based on postoperative SARS-CoV-2 rates and mortality in an international cohort study (surgical patients), and community SARS-CoV-2 incidence and case fatality data (general population). NNV estimates were stratified by age (18-49, 50-69, 70 or more years) and type of surgery. Best-and worst-case scenarios were used to describe uncertainty. Results: NNVs were more favourable in surgical patients than the general population. The most favourable NNVs were in patients aged 70 years or more needing cancer surgery (351; best case 196, worst case 816) or non-cancer surgery (733; best case 407, worst case 1664). Both exceeded the NNV in the general population (1840; best case 1196, worst case 3066). NNVs for surgical patients remained favourable at a range of SARS-CoV-2 incidence rates in sensitivity analysis modelling. Globally, prioritizing preoperative vaccination of patients needing elective surgery ahead of the general population could prevent an additional 58 687 (best case 115 007, worst case 20 177) COVID-19-related deaths in 1 year. Conclusion: As global roll out of SARS-CoV-2 vaccination proceeds, patients needing elective surgery should be prioritized ahead of the general population.

Research paper thumbnail of Spontaneous thrombosis of a vein of Galen malformation associated with acute sinusitis: a case report

Child's Nervous System, 2021

The vein of Galen malformation is caused by an abnormal shunting between choroidal arteries and t... more The vein of Galen malformation is caused by an abnormal shunting between choroidal arteries and the median prosencephalic vein during embryological development, leading to increased blood flow to the deep cerebral veins, intracranial damage, and systemic repercussions. Idiopathic spontaneous thrombosis of a vein of Galen malformation is rare, and its association with acute sinusitis has not been reported in the literature. We present the case of a girl with a postnatal diagnosis of a vein of Galen malformation at the age of 16 months, with secondary pulmonary hypertension that was adequately controlled with spironolactone. At 3 years old, while expecting elective endovascular treatment, the patient developed spontaneous thrombosis of the vein of Galen malformation, concomitant to an acute sinusitis episode, with complete resolution of the vascular malformation and secondary pulmonary hypertension. The patient continued with normal neurological development over a 5-year follow-up. We discuss the main pathophysiologic mechanisms that can explain spontaneous thrombosis of VOGMs and the patient's outcome. Awareness of different mechanisms that can lead to spontaneous thrombosis can help in the decision-making process and prompt targeted approaches to individual patients with a vein of Galen malformation.

Research paper thumbnail of SARS-CoV-2 vaccination modelling for safe surgery to save lives: data from an international prospective cohort study

British Journal of Surgery, 2021

Background: Preoperative SARS-CoV-2 vaccination could support safer elective surgery. Vaccine num... more Background: Preoperative SARS-CoV-2 vaccination could support safer elective surgery. Vaccine numbers are limited so this study aimed to inform their prioritization by modelling. Methods: The primary outcome was the number needed to vaccinate (NNV) to prevent one COVID-19-related death in 1 year. NNVs were based on postoperative SARS-CoV-2 rates and mortality in an international cohort study (surgical patients), and community SARS-CoV-2 incidence and case fatality data (general population). NNV estimates were stratified by age (18-49, 50-69, 70 or more years) and type of surgery. Best-and worst-case scenarios were used to describe uncertainty. Results: NNVs were more favourable in surgical patients than the general population. The most favourable NNVs were in patients aged 70 years or more needing cancer surgery (351; best case 196, worst case 816) or non-cancer surgery (733; best case 407, worst case 1664). Both exceeded the NNV in the general population (1840; best case 1196, worst case 3066). NNVs for surgical patients remained favourable at a range of SARS-CoV-2 incidence rates in sensitivity analysis modelling. Globally, prioritizing preoperative vaccination of patients needing elective surgery ahead of the general population could prevent an additional 58 687 (best case 115 007, worst case 20 177) COVID-19-related deaths in 1 year. Conclusion: As global roll out of SARS-CoV-2 vaccination proceeds, patients needing elective surgery should be prioritized ahead of the general population.

Research paper thumbnail of Timing of surgery following SARS-CoV-2 infection: an international prospective cohort study

Anaesthesia, 2021

Peri-operative SARS-CoV-2 infection increases postoperative mortality. The aim of this study was ... more Peri-operative SARS-CoV-2 infection increases postoperative mortality. The aim of this study was to determine the optimal duration of planned delay before surgery in patients who have had SARS-CoV-2 infection. This international, multicentre, prospective cohort study included patients undergoing elective or emergency surgery during October 2020. Surgical patients with pre-operative SARS-CoV-2 infection were compared with those without previous SARS-CoV-2 infection. The primary outcome measure was 30-day postoperative mortality. Logistic regression models were used to calculate adjusted 30-day mortality rates stratified by time from diagnosis of SARS-CoV-2 infection to surgery. Among 140,231 patients (116 countries), 3127 patients (2.2%) had a pre-operative SARS-CoV-2 diagnosis. Adjusted 30-day mortality in patients without SARS-CoV-2 infection was 1.5% (95%CI 1.4-1.5). In patients with a pre-operative SARS-CoV-2 diagnosis, mortality was increased in patients having surgery within 0-2 weeks, 3-4 weeks and 5-6 weeks of the diagnosis (odds ratio (95%CI) 4.1 (3.3-4.8), 3.9 (2.6-5.1) and 3.6 (2.0-5.2), respectively). Surgery performed ≥ 7 weeks after SARS-CoV-2 diagnosis was associated with a similar mortality risk to baseline (odds ratio (95%CI) 1.5 (0.9-2.1)). After a ≥ 7 week delay in undertaking surgery following SARS-CoV-2 infection, patients with ongoing symptoms had a higher mortality than patients whose symptoms had resolved or who had been asymptomatic (6.0% (95%CI 3.2-8.7) vs. 2.4% (95%CI 1.4-3.4) vs. 1.3% (95%CI 0.6-2.0), respectively). Where possible, surgery should be delayed for at least 7 weeks following SARS-CoV-2 infection. Patients with ongoing symptoms ≥ 7 weeks from diagnosis may benefit from further delay.

Research paper thumbnail of Cell therapy for spinal cord injury with olfactory ensheathing glia cells (OECs)

Glia, Jul 13, 2018

The prospects of achieving regeneration in the central nervous system (CNS) have changed, as most... more The prospects of achieving regeneration in the central nervous system (CNS) have changed, as most recent findings indicate that several species, including humans, can produce neurons in adulthood. Studies targeting this property may be considered as potential therapeutic strategies to respond to injury or the effects of demyelinating diseases in the CNS. While CNS trauma may interrupt the axonal tracts that connect neurons with their targets, some neurons remain alive, as seen in optic nerve and spinal cord (SC) injuries (SCIs). The devastating consequences of SCIs are due to the immediate and significant disruption of the ascending and descending spinal pathways, which result in varying degrees of motor and sensory impairment. Recent therapeutic studies for SCI have focused on cell transplantation in animal models, using cells capable of inducing axon regeneration like Schwann cells (SchCs), astrocytes, genetically modified fibroblasts and olfactory ensheathing glia cells (OECs). N...

Research paper thumbnail of Gliomas: New Perspectives in Diagnosis, Treatment and Prognosis

Current topics in medicinal chemistry, Jan 3, 2017

Gliomas are central nervous system tumors originated from glial cells, whose incidence and mortal... more Gliomas are central nervous system tumors originated from glial cells, whose incidence and mortality is expected to rise in coming years, especially in developing countries. Diagnosis and classification of gliomas have largely relied on tumor histopathologic features that provide limited information regarding response to therapy or prognosis. Current treatment of gliomas is surgery combined with chemotherapy and/or radiotherapy. However, many tumors show a high resistance to these interventions, and recurrences are frequent since conventional therapies do not take into account the unique molecular features of different subtypes of glioma. Molecular genetics provide new insights in classifying gliomas and predicting response to therapy that can range from conventional treatments to new revolutionary therapeutic approaches. This article offers a review of the intracellular signaling pathways involved in carcinogenesis of gliomas, as well as a description of new tools for their diagnos...