NEUROANESTHESIA in neuroscience and .pptx

neuroscience

1. NEUROANESTHESIA SULAYMAN SALAUDEEN A. 239091006 ABOLARIN AYO T. 239091011

2. OUTLINE INTRODUCTION BASIC NEUROANATOMY & NEUROPHYSIOLOGY STRUCTURES AFFECTED BY NEUROANESTHESIA PATHWAYS AND CIRCUITS INVOLVED IN NEUROANESTHESIA MECHANISM OF ACTION NEUROANESTHESIA AND THE BRAIN NEUROANESTHESIA AND THE SPINAL CORD REFERENCES

3. INTRODUCTION TO NEUROANESTHESIA A specialized branch of anesthesia focused on the care of patients undergoing surgery involving the brain, spine, and PNS. Combines principles of neurophysiology, neurosurgery, anesthesiology.

4. BASIC NEUROANATOMY & NEUROPHYSIOLOGY The CNS is a complex network of interconnected neurons that process information and coordinate responses throughout the body. Neuronal signaling involves the transmission of signals through synapses ( Perrais et al., 2023) The blood-brain barrier is a semipermeable membrane that separates the circulating blood from the brain extracellular fluid (Lim et al., 2022)

5. Fig: Image of the brain and its termination in the spinal cord. ( Omidi & Barar , 2012)

6. Fig.: The Blood-Brain Barrier (Lim et al., 2022).

7. STRUCTURES AFFECTED BY NEUROANESTHESIA Neuroanesthesia impacts several brain structures; Cerebral Cortex Subcortical structures (Thalamus, Basal Ganglia) Brainstem (Reticular formation, Cranial nerve nuclei). Spinal Cord (Ma, Uejima & Bebawy , 2023).

8. Fig.: Depiction of cortical and subcortical brain regions. ( Tamuli et al., 2021)

9. PATHWAYS AND CIRCUITS INVOLVED IN NEUROANESTHESIA Ascending Sensory Pathways: Spinothalamic tract, Dorsal Column Medial Lemniscal Pathway Descending Motor Pathways: Corticospinal tract, Extrapyramidal tracts. Pain Pathways: Peripheral, Spinal, Supraspinal. ( Nikolenko et al., 2022).

10. Fig.: Major ascending pathways of the CNS. ( Nikolenko et al., 2022).

11. Fig.: Ascending pathways of nociceptive fibres . ( Nikolenko et al., 2022).

12. Fig.: Representative diagram of corticospinal tracts. ( Nikolenko et al., 2022).

13. PATHWAYS AND CIRCUITS INVOLVED IN NEUROANESTHESIA Neuroanesthesia modulates the ascending and descending pain pathways within the CNS by altering the transmission of signals. A key mechanism is through neurotransmitter system modulation in the CNS. In the descending pathway, neuroanesthesia acts via disinhibition, causing the modulation of pain signals. (Winters et al., 2022)

14. PATHWAYS AND CIRCUITS INVOLVED IN NEUROANESTHESIA Neuroanesthesia impacts the structural connectivity of the ascending and descending pathways (Cai et al., 2023). Neural plasticity is affected, leading to a modulation of ascending and descending pathways (Cai et al., 2023). Metabolic pathways are affected, influencing signaling cascades involved in pain processing (Liu et al., 2023).

15. NEUROANESTHESIA MECHANISM OF ACTION Local anesthesia works by blocking nerve impulses in a specific area, inhibiting pain sensation without affecting consciousness. Regional anesthesia involves blocking sensation in a larger region of the body by targeting specific nerve pathways. General anesthesia induces a reversible state of unconsciousness and loss of sensation throughout the entire body. (Ma, Uejima & Bebawy , 2023).

16. PRINCIPLES OF NEUROANESTHESIA There are certain key principles which aid in risk minimization and promotion of better outcomes including the following; Maintenance of Cerebral Perfusion and Oxygenation Control of Intracranial Pressure Anesthetic Agent Selection Neurophysiological Monitoring (He et al., 2023)

17. Fig.: Image showing a normal optic disk and one with Increased Intracranial Pressure. Wiki

18. NEUROANESTHESIA AND THE BRAIN Cerebral Cortex: Anesthetics suppress cortical activity by acting on neurotransmitter systems, particularly GABA. Limbic System: Anesthetics act on amygdala and hippocampus, leading to transient amnesia and diminished emotional response. Thalamus: Anesthetics inhibit thalamic relay capabilities, preventing the brain from processing external stimuli. (Mandal, Mukherjee, Acharjee & Chakrabarti, 2022)

19. NEUROANESTHESIA AND THE BRAIN Hypothalamus: Anesthetics impact autonomic responses and endocrine regulations, causing altered metabolic states. Brainstem: Anesthetics suppress RAS, leading to loss of consciousness. Cerebellum: Anesthetics disrupt cerebellar pathways, disrupting timing and precision of motor responses. (Mandal, Mukherjee, Acharjee & Chakrabarti, 2022)

20. Fig.: Image showing the right hemisphere of the brain. (Mandal, Mukherjee, Acharjee & Chakrabarti, 2022)

21. NEUROANESTHESIA AND THE SPINAL CORD Dorsal Horn: Anesthetics provide analgesia by preventing transmission of noxious stimuli to higher centres . Ventral Horn: Anesthetics inhibit motor neurons, leading to muscle relaxation. Spinal Anesthesia (Nakatani, 2023)

22. Fig.: Diagram showing cross-section of Spinal Cord. (Nakatani, 2023)

23. PHARMACOLOGY IN NEUROANESTHESIA Commonly used anesthetic agents in neuroanesthesia include both local and inhalational agents. Local agents include procaine, lidocaine, and bupivacaine, and inhalational agents include isoflurane, sevoflurane, and desflurane. ( Mekonnen , AbdeRehman & Seyaka , 2023).

24. PHARMACOLOGY IN NEUROANESTHESIA Adjuvant medications plays a critical role in enhancing the effects of primary anesthetic agent. They aid in managing specific challenges associated with neurosurgical procedures. Examples include induction agents (Thiopental, propofol) and neuromuscular blocking agents (Rocuronium) (ÇETİNKAYA et al., 2022)

25. PHARMACOLOGY IN NEUROANESTHESIA In considering choice of neuroanesthesia to be employed, several factors must be considered to ensure safety and efficacy. Also, the balance between achieving adequate depth of anesthesia and minimizing adverse effects is important. The pharmacological properties of the agents, including their mechanisms of action, potency, and potential side effects must also be considered.

26. TECHNIQUES IN NEUROANESTHESIA General anesthesia serves as the cornerstone of neuroanesthetic management as it controls unconsciousness while maintaining vital physiological functions ( Mekonnen , AbdeRehman & Seyaka , 2023). A commonly-employed technique is the asleep-awake-asleep approach, which allows neurosurgeons to interact with patients during critical phases of the operation (D’Onofrio et al., 2023).

27. TECHNIQUES IN NEUROANESTHESIA For neuroanesthesia , regional anesthesia techniques are favoured such as scalp blocks, thereby reducing pain perception during neurosurgical procedures. By focusing on regional nerve blockade, neuroanesthesiologists can tailor anesthesia regimens to address the unique pain pathways associated with cranial surgeries. (Ma, Uejima & Bebawy , 2023).

28. TECHNIQUES IN NEUROANESTHESIA Awake craniotomy allows for intraoperative neurological assessments and functional mapping while the patient remains conscious (Khan, Rahman, Ziauddin, Chowdhury & Hasan, 2024) . It reduces patient LOS and is cost-effective. It helps to ensure maximal positive outcome while preserving essential brain functions (Moniz-Garcia et al., 2024).

29. Fig: An open craniotomy to excise a glioma. Neurosurgery Journal

30. TECHNIQUES IN NEUROANESTHESIA Adjuvant medications like dexmedetomidine have emerged, offering sedative properties without compromising the patient's ability to cooperate during intraoperative assessments (D’Onofrio et al., 2023). Similarly, the use of techniques such as 5-ALA fluorescence, intraoperative ultrasound and intraoperative neuromonitoring have been employed in awake craniotomy (Kaye et al., 2022)

31. MONITORING & SAFETY In neuroanesthesia , ensuring patient safety and optimal outcomes during neurosurgical procedures is paramount. The goals include maintenance of neurocognitive development and monitoring impacts of anesthetic agents on the CNS. (Mandal, Mukherjee, Acharjee & Chakrabarti, 2022)

32. MONITORING & SAFETY Techniques in patient monitoring include; Trans-nasal humidified rapid insufflation ventilatory exchange (THRIVE) High-flow nasal oxygenation (HFNO) Motor Evoked Potential (MEP) monitoring Somatosensory Evoked Potential (SEP) monitoring Intraoperative Stimulation Mapping Cerebral Perfusion Pressure Optimization Intracranial Pressure monitoring Multimodal intraoperative neurophysiological monitoring. (Majumdar et al., 2023).

33. POST-OPERATIVE CONSIDERATIONS Post-operative care following neuroanesthesia involves ensuring a smooth transition from the operating room to the recovery phase. Neurological assessment is carried out for monitoring signs of neurological deficits or complications post-surgery (Majumdar et al., 2023). Post-operative follow-up care significantly impacts surgical outcomes and patient satisfaction in neuroanesthesia ( Sragi , Farrell, Vasan & Courey , 2023).

34. JOURNAL ARTICLE CRITIQUE Title: Awake Craniotomy Program Implementation Authors: Moniz-Garcia et al., 2024 Abstract Summary: The study was conducted to assess the cost utility of introducing a standardized program of awake craniotomies at Mayo Clinic Florida. Treatment with an awake craniotomy before standardization (2016-2018) was compared with treatment with awake craniotomy after standardization (2018-2021). There was a generalized reduction in length of stay, ICU admission time, and direct medical costs with implementation of an optimized protocol.

35. JOURNAL ARTICLE CRITIQUE Strengths: Comprehensive data analysis; Demonstration of cost savings; Clear measurement of outcomes; Multidisciplinary approach; Institutional context. Weaknesses: Retrospective design; Exclusion criteria; Sample size.

36. REFERENCES Cai, B., Wu, D., Xie, H., Chen, Y., Wang, H., Jin, S., … & Zhang, X. (2023). A direct spino -cortical circuit bypassing the thalamus modulates nociception. Cell Research, 33(10), 775-789. https://doi.org/10.1038/s41422-023-00832-0 ÇETİNKAYA, H., SARIHASAN, B. B., BİLGİN, S., DOST, B., TURUNÇ, E., & ÇETİNKAYA, G. (2022). Retrospective analysis of the patients undergoing neuroanaesthesia between the years 2015-2019. Journal of Experimental and Clinical Medicine, 39(2), 521–524. https://doi.org/10.52142/omujecm.39.2.42 D’Onofrio, G., Izzi , A., Manuali , A., Bisceglia , G., Tancredi, A., Marchello , V., … Del, A. (2023). Anesthetic Management for Awake Craniotomy Applied to Neurosurgery. Brain Sciences, 13(7), 1031–1031. https://doi.org/10.3390/brainsci13071031

37. REFERENCES He, Y., Liu, T., He, Q., Ke, W., Li, X., Du, J., … Peng, B. (2023). Microglia facilitate and stabilize the response to general anesthesia.  BioRxiv (Cold Spring Harbor Laboratory). https://doi.org/10.1101/2023.10.06.561235 Kaye, B., Augusto, R., MacKinnon, G., Dabecco , R., Ibrahim, B., Ali, A., … Badih Adada . (2022). Wide Dissection Trans-Sulcal Approach for Resection of Deep Intra-Axial Lesions in Eloquent Brain Areas. Current Oncology, 29(10), 7396–7410. https://doi.org/10.3390/curroncol29100581 Khan, R. A., Rahman, M. M., Ziauddin, Md., Chowdhury, M., & Hasan, M. (2024). Awake brain mapping by direct cortical stimulation; technical note to get higher resection rate and low morbidity in low grade glioma patients. Annals of Medicine and Surgery. https://doi.org/10.1097/ms9.0000000000001837 Lim, J. W., Park, M. A., & Kim, J. (2022). Photo‐synaptic oxide transistors with al2o3/ siox stacked gate dielectric exhibiting 1024 conduction states with good linearity. Advanced Electronic Materials, 8(10). https://doi.org/10.1002/aelm.202200494 Liu, T., Zhou, N., Fu, Y., Feng, W., & Zheng, X. (2023). Systemic metabolomics characterization of the ascending and descending property.. https://doi.org/10.21203/rs.3.rs-3187361/v1

38. REFERENCES Ma, K., Uejima , J. L., & Bebawy , J. F. (2023). Regional Anesthesia Techniques in Modern Neuroanesthesia Practice: A Narrative Review of the Clinical Evidence. Journal of Neurosurgical Anesthesiology, 36(2), 109–118. https://doi.org/10.1097/ana.0000000000000911 Majumdar, J. R., Fromkin , J. B., Yermal , S. J., Fatata ‐Haim, A. M., Barton‐Burke, M., & Jairath , N. N. (2023). Research Electronic Data Capture ( REDCap ) in an outpatient oncology surgery setting to securely email, collect, and manage survey data. Journal of Advanced Nursing, 80(6), 2592–2597. https://doi.org/10.1111/jan.15983 Mandal, T., Mukherjee, M., Acharjee , A., & Chakrabarti, S. (2022). The comparative effects of desflurane and isoflurane on intraoperative cerebral hemodynamics, cardiovascular changes, and post-operative recovery in patients undergoing craniotomy for supratentorial tumors. Asian Journal of Medical Sciences, 13(7), 63–70. https://doi.org/10.3126/ajms.v13i7.43108

39. REFERENCES Mekonnen , A., Abderehman , K., & Seyaka , F. (2023). Review on Commonly Used Veterinary Anesthetic Drugs in Small Ruminants. Veterinary Sciences, 9(2). https://doi.org/10.17582/journal.vsrr/2023/9.2.103.113 Moniz-Garcia, D., Bojaxhi , E., Borah, B. J., Dholakia, R., Kim, H., Sousa-Pinto, B., … Quiñones -Hinojosa, A. (2024). Awake Craniotomy Program Implementation. JAMA Network Open, 7(1), e2352917–e2352917. https://doi.org/10.1001/jamanetworkopen.2023.52917 Nakatani, R. (2023). Simulation in anesthesia for perioperative neuroscience: present and future. Journal of Neurosurgical Anesthesiology, 36(1), 4-10. https://doi.org/10.1097/ana.0000000000000939 Nikolenko , V. N., Shelomentseva , E. M., Tsvetkova, M. M., Abdeeva , E. I., Giller , D. B., Babayeva , J. V., … Sinelnikov , M. Y. (2022). Nociceptors: Their Role in Body’s Defenses, Tissue Specific Variations and Anatomical Update. Journal of Pain Research, 15, 867–877. https://doi.org/10.2147/JPR.S348324 Omidi , Y., & Barar , J. (2012). Impacts of Blood-Brain Barrier in Drug Delivery and Targeting of Brain Tumors. BioImpacts : BI, 2(1), 5–22. https://doi.org/10.5681/bi.2012.002

40. REFERENCES Perrais , D., Sposini , S., & Angibaud , J. (2023). Imaging of post-synaptic membrane trafficking in neuronal dendrites: progress, limitations, and new developments. Neurophotonics, 10(04). https://doi.org/10.1117/1.nph.10.4.044404 Sragi , Z., Farrell, B., Vasan , V., & Courey , M. S. (2023). Inclusive Healthcare Settings: Promoting Post-operative Follow-up in Transgender Voice Care through Awareness and Education. 4(1), 1–6. https://doi.org/10.47739/2578-3696.womenshealth.1013 Tamuli , D., Kaur, M., Jaryal , A. K., Srivastava, A. K., Kumaran, S. S., & Deepak, K. K. (2021). Structural atrophy of central autonomic network correlates with the functional attributes of autonomic nervous system in spinocerebellar ataxia patients. Journal of Clinical Neuroscience, 93, 274–281. https://doi.org/10.1016/j.jocn.2021.07.031 Winters, B., Lau, B., & Vaughan, C. (2022). Cannabinoids and opioids differentially target extrinsic and intrinsic gabaergic inputs onto the periaqueductal grey descending pathway. Journal of Neuroscience, JN-RM-0997-22. https://doi.org/10.1523/jneurosci.0997-22.2022

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