Nils Petersen, MD, PhD, MSc
Associate Professor TermCards
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Staff Neurointensivist, Neuroscience Intensive Care Unit
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View this doctor's clinical profile on the Yale Medicine website for information about the services we offer and making an appointment.
View Doctor ProfileAdditional Titles
Staff Neurointensivist, Neuroscience Intensive Care Unit
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Are You a Patient?
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Staff Neurointensivist, Neuroscience Intensive Care Unit
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About
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Titles
Associate Professor Term
Staff Neurointensivist, Neuroscience Intensive Care Unit
Biography
Nils Petersen obtained his medical degree and a doctorate in neuroscience from Christian-Albrechts University in Kiel, Germany. He completed his residency in Neurology at Mount Sinai Hospital in New York, NY, where he also served as chief resident in his final year. He then pursued fellowship training in Vascular Neurology at Columbia University and simultaneously completed a Master's degree in Patient-Oriented Research at the Mailman School of Public Health. He next completed a fellowship in Neurocritical Care at Massachusetts General Hospital and also obtained certification in Neurovascular Ultrasound from the American Society of Neuroimaging.
He is the director of the Yale Cerebral Blood Flow Laboratory, which provides the infrastructure for advanced monitoring of brain physiology. His clinical and research interests are in using ultrasound and novel neuromonitoring modalities to better understand brain blood flow regulation. His ongoing clinical care of patients in the Neurologic Intensive Care Unit and Stroke Service continues to inspire his research pursuits, with the goal of improving patient outcomes and preventing neurologic worsening after acute ischemic stroke.
Appointments
Neurology
Associate Professor on TermPrimary
Other Departments & Organizations
- Center for Neuroepidemiology and Clinical Neurological Research
- Janeway Society
- Neurocritical Care & Emergency Surgery
- Neurology
- Petersen Lab
- Stroke Center
- Stroke Telemedicine Program
- Vascular Neurology
- Yale Medicine
Education & Training
- Fellowship
- Massachusetts General Hospital/Brigham and Women's Hospital (2014)
- MSc
- Mailman School of Public Health, Columbia University (2013)
- Fellowship
- Columbia University/New York Presbyterian (2012)
- Residency
- Mount Sinai Medical Center (2010)
- Residency
- University Hospital Schleswig-Holstein (2006)
- PhD
- Christian-Albrechts-University (2004)
- MD
- Christian-Albrechts-University (2004)
Research
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Overview
Medical Research Interests
ORCID
0000-0001-9711-3340- View Lab Website
Petersen Lab
Research at a Glance
Yale Co-Authors
Publications Timeline
Research Interests
Kevin Sheth, MD
Charles Matouk, MD
Guido J. Falcone, MD, ScD, MPH
Adam de Havenon, MD, MSCI
Emily J. Gilmore, MD, FNCS, FACNS
Lauren Hachmann Sansing, MD, MS, FAHA, FANA
Publications
2025
Aggregated postpartum cerebral autoregulatory curves in normotensive individuals, preeclampsia with severe features, and superimposed preeclampsia with severe features
Woolcock H, Katsidoniotaki M, Meng L, Haghighi N, van Wingerden A, Alian A, Booker W, Bello N, Marshall R, Kougioumtzoglou I, Petersen N, Miller E. Aggregated postpartum cerebral autoregulatory curves in normotensive individuals, preeclampsia with severe features, and superimposed preeclampsia with severe features. Physiological Measurement 2025, 46: 09nt01. PMID: 40845907, PMCID: PMC12441783, DOI: 10.1088/1361-6579/adfeb4.Peer-Reviewed Original ResearchMeSH Keywords and ConceptsConceptsMean arterial pressureSuperimposed preeclampsiaPreeclampsia groupProspective observational studyNormotensive groupCerebral blood velocityRetrospective analysisPostpartum participantsAutoregulatory rangeRetrospective analysis of dataAutoregulatory curveContinuous mean arterial pressureImpaired cerebral autoregulationSevere featuresChronic hypertensionPreeclampsiaArterial pressureCerebral autoregulatory curveNormotensive individualsFinger plethysmographyPostpartum periodPair-wise comparisonsTranscranial DopplerAutoregulation curveCerebral autoregulationImpact of Nimodipine-Induced Blood Pressure Reductions on Cerebral Autoregulation and Functional Outcome After Aneurysmal Subarachnoid Hemorrhage
Stoehr K, Bartolome D, Jayasundara S, Thinzar P, Vargas D, Kim J, Magid-Bernstein J, O’Keefe L, de Havenon A, Hebert R, Matouk C, Sheth K, Gilmore E, Ortega-Gutierrez S, Petersen N. Impact of Nimodipine-Induced Blood Pressure Reductions on Cerebral Autoregulation and Functional Outcome After Aneurysmal Subarachnoid Hemorrhage. Neurocritical Care 2025, 1-11. PMID: 40847251, DOI: 10.1007/s12028-025-02338-6.Peer-Reviewed Original ResearchCitationsAltmetricConceptsAneurysmal subarachnoid hemorrhageMean arterial pressureAssociated with worse functional outcomeBP reductionFunctional outcomesNimodipine administrationSubarachnoid hemorrhageHunt & Hess scoreBlood pressureAssociated with BP reductionSevere aneurysmal subarachnoid hemorrhageModified Fisher gradeResponse to nimodipineSensitive to nimodipineCerebral autoregulationDelayed Cerebral IschemiaBlood pressure reductionRegional oxygen saturationObservational cohort studyModified Rankin ScaleLimits of autoregulationFisher gradeHess scoreAneurysm securementNeurological outcomePolygenic Resistance to Blood Pressure Treatment and Stroke Risk: Insights from the All of Us Research Program
Huo S, Rivier C, Clocchiatti‐Tuozzo S, Renedo D, Petersen N, de Havenon A, Meeker D, Zhao H, Ohno‐Machado L, Sheth K, Falcone G. Polygenic Resistance to Blood Pressure Treatment and Stroke Risk: Insights from the All of Us Research Program. Annals Of Neurology 2025 PMID: 40827941, DOI: 10.1002/ana.78009.Peer-Reviewed Original ResearchCitationsAltmetricConceptsUs Research ProgramUncontrolled hypertensionSystolic BPGenetic riskSusceptibility to hypertensionRates of uncontrolled hypertensionPolygenic risk scoresAssociated with higher systolic BPOdds of uncontrolled hypertensionCox proportional hazards regressionUnited Kingdom BiobankGenetic association studiesHigh-risk individualsHigher systolic BPProportional hazards regressionBlood pressure treatmentIncident strokeStroke hazardBlood pressureHigher RatesSystolic blood pressureHypertensive adultsDiagnosed hypertensionBP medicationsHazards regressionEarly CSF inflammatory markers after aneurysmal subarachnoid hemorrhage and their relationship to disease severity and shunt placement
Magid-Bernstein J, Yan J, Herman A, He Z, Johnson C, Beatty H, Choi R, Velazquez S, Sorensen G, Jayasundara S, Grychowski L, Amllay A, Falcone G, Kim J, Petersen N, O’Keefe L, Gilmore E, Matouk C, Sheth K, Sansing L. Early CSF inflammatory markers after aneurysmal subarachnoid hemorrhage and their relationship to disease severity and shunt placement. Journal Of Stroke And Cerebrovascular Diseases 2025, 34: 108395. PMID: 40639751, PMCID: PMC12333380, DOI: 10.1016/j.jstrokecerebrovasdis.2025.108395.Peer-Reviewed Original ResearchCitationsMeSH Keywords and ConceptsConceptsPermanent shunt placementAneurysmal subarachnoid hemorrhage patientsGranulocyte-colony stimulating factorAneurysmal subarachnoid hemorrhageVascular endothelial growth factorCC motif chemokine ligand 2Shunt placementCerebrospinal fluidCerebrospinal fluid samplesInterleukin-6Interleukin-8Disease severityPreclinical modelsSubarachnoid hemorrhageModified Fisher scale scoresModels of CNS inflammationShunt-dependent hydrocephalusAssociated with clinical severityConcentrations of interleukin-6Post-hemorrhagic hydrocephalusMotif chemokine ligand 2Panel of cytokinesCSF inflammatory markersEndothelial growth factorCerebrospinal fluid concentrationsIncreased Blood Pressure Variability is Associated with More Time Spent Outside Personalized Limits of Cerebral Autoregulation in Postpartum Preeclampsia
Kirschner M, Woolcock Martinez H, Haghighi N, Booker W, Marshall R, Bello N, Petersen N, Miller E. Increased Blood Pressure Variability is Associated with More Time Spent Outside Personalized Limits of Cerebral Autoregulation in Postpartum Preeclampsia. Neurocritical Care 2025, 1-11. PMID: 40629211, DOI: 10.1007/s12028-025-02316-y.Peer-Reviewed Original ResearchAltmetricConceptsMeasured mean arterial blood pressureBlood pressure variabilityHigh blood pressure variabilityIncreased blood pressure variabilityRegional oxygen saturationCerebral autoregulationPostpartum patientsTreatment of severe preeclampsiaOxygen saturationMean arterial blood pressureMedian monitoring timePilot clinical trialPressure variabilityCalculate blood pressure variabilityResultsWe analyzed dataArterial blood pressurePostpartum maternal mortalitySevere preeclampsiaPostpartum preeclampsiaObservation armMaternal outcomesIntracranial hemorrhageSympathetic hyperreactivityPreeclampsiaMaternal brainDifferent Responses to Blood Pressure Reduction in Lobar and Deep Intracerebral Hemorrhage
Clocchiatti-Tuozzo S, Rivier C, Qureshi A, Renedo D, Huo S, Matouk C, Petersen N, de Havenon A, Sheth K, Rabinstein A, Falcone G, Hawkes M. Different Responses to Blood Pressure Reduction in Lobar and Deep Intracerebral Hemorrhage. Neurocritical Care 2025, 43: 607-615. PMID: 40293696, DOI: 10.1007/s12028-025-02269-2.Peer-Reviewed Original ResearchAltmetricConceptsRenal adverse eventsDeep intracerebral hemorrhageIntensive BP reductionRisk of renal adverse eventsRisk of HEHematoma expansionBP reductionATACH-2Intracerebral hemorrhageLobar intracerebral hemorrhageFunctional outcomesAntihypertensive Treatment of Acute Cerebral Hemorrhage IIAcute spontaneous intracerebral hemorrhageAcute intracerebral hemorrhageSpontaneous intracerebral hemorrhageAssociated with reduced riskUnfavorable functional outcomeBlood pressure reductionRandomized clinical trialsMultivariate logistic regression resultsPost Hoc AnalysisAntihypertensive treatmentAdverse eventsClinical trialsIncreased riskPolygenic Resistance to Vascular Risk Factor Control in Stroke Survivors (S30.006)
Huo S, Rivier C, Clocchiatti-Tuozzo S, Renedo D, Torres-Lopez V, Sunmonu N, Petersen N, De Havenon A, Sheth K, Falcone G. Polygenic Resistance to Vascular Risk Factor Control in Stroke Survivors (S30.006). Neurology 2025, 104 DOI: 10.1212/wnl.0000000000208802.Peer-Reviewed Original ResearchAltmetricEnhancing Autoregulation-guided Blood Pressure Management after Large-vessel Ischemic Stroke (P9-13.010)
Thinzar P, Jayasundara S, Estrella D, Stoehr K, Gutierrez S, Petersen N. Enhancing Autoregulation-guided Blood Pressure Management after Large-vessel Ischemic Stroke (P9-13.010). Neurology 2025, 104 DOI: 10.1212/wnl.0000000000211008.Peer-Reviewed Original ResearchBlood Pressure Variability as a Marker of Sympathetic Hyperreactivity in Postpartum Patients with Preeclampsia, with and without Chronic Hypertension (P2-7.003)
Kirschner M, Martinez H, Taliadouros L, Haghighi N, Castro P, Booker W, Bello N, Petersen N, Miller E. Blood Pressure Variability as a Marker of Sympathetic Hyperreactivity in Postpartum Patients with Preeclampsia, with and without Chronic Hypertension (P2-7.003). Neurology 2025, 104 DOI: 10.1212/wnl.0000000000211236.Peer-Reviewed Original ResearchElevated Pre-hospital Blood Pressure is Associated with Reduced Infarct Volume in Large Vessel Occlusion Ischemic Strokes (P12-13.016)
Galecio-Castillo M, Shogren S, Olexa M, Begunova Y, Cruz L, Kalakoti P, Brito-Alvarado A, Petersen N, Gutierrez S. Elevated Pre-hospital Blood Pressure is Associated with Reduced Infarct Volume in Large Vessel Occlusion Ischemic Strokes (P12-13.016). Neurology 2025, 104 DOI: 10.1212/wnl.0000000000212687.Peer-Reviewed Original Research
Clinical Trials
Current Trials
Comparison of Anti-coagulation and Anti-Platelet Therapies for Intracranial Vascular Atherostenosis (CAPTIVA)
HIC ID2000031893RoleSub InvestigatorPrimary Completion Date03/07/2028Recruiting ParticipantsGenderBothAge30 years - 80 yearsBlood PREssure Augmentation in Large-vessel Occlusion Stroke Study (PRESS)
HIC ID2000022525RolePrincipal InvestigatorPrimary Completion Date04/30/2019Recruiting ParticipantsGenderBothAge18+ yearsBrain Oxygen Optimization in Severe TBI, Phase 3 (BOOST3)
HIC ID2000024956RoleSub InvestigatorPrimary Completion Date07/01/2023Recruiting ParticipantsGenderBothAge14+ yearsAnticoagulation for Stroke Prevention and Recovery After ICH (ASPIRE)
HIC ID2000026409RoleSub InvestigatorPrimary Completion Date04/30/2028Recruiting ParticipantsGenderBothAge18+ yearsTransforming Acute Stroke Detection through Real Time Neurological Monitoring
HIC ID1605017863RoleSub InvestigatorPrimary Completion Date07/01/2017Recruiting ParticipantsGenderBothAge18+ years
Clinical Care
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Overview
Nils Petersen, MD, PhD, is a neurointensivist in the neuroscience intensive care unit (NICU) of Yale New Haven Hospital. He treats life-threatening diseases that involve the brain, spinal cord and nerves, from stroke to central nervous system infections, neuromuscular diseases and neurosurgical post-operative care. “To be a skilled neurologist requires not only knowledge of how the brain works and the latest treatments,” he says, “but also the clinical acumen to pick up subtle exam findings, interpret complicated histories and apply critical thinking skills to compose the best treatment plan for each patient.”
He was recruited by Yale in 2014 to design and implement a state-of-the-art neurovascular ultrasound lab. “Hospitalization after stroke or in the NICU represents an important and vulnerable time for both patients and families, a time during which physicians have the most impact,” he says. “I feel privileged to be a part of this journey for my patients and their families, a journey that continues to inspire me both personally and scientifically on a regular basis.”
An assistant professor at Yale School of Medicine, Dr. Petersen hopes his research on brain blood flow and how it is affected by neurologic injury, particularly stroke, will help doctors improve functional outcomes after stroke.
Clinical Specialties
Fact Sheets
Ischemic Stroke
Learn More on Yale MedicineSudden Cardiac Arrest
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