Dr Mehr

NEURAXIAL ANESTHESIANEURAXIAL ANESTHESIABasic OverviewBasic Overview

By:By:Ismail A. Mehr, M.D.Ismail A. Mehr, M.D.December 29December 29thth, 2014, 2014

DisclosureIsmail Mehr MD

I have NO actual or potential conflict of interest in relation to this activity.

I do not have any relevant financial relationships with any commercial interests.

Neuraxial AnesthesiaNeuraxial Anesthesia EpiduralEpidural Intrathecal – “Spinal”Intrathecal – “Spinal”

Neuraxial Anesthesia Neuraxial Anesthesia Neuraxial anesthesia had its greatest Neuraxial anesthesia had its greatest

impact in obstetricsimpact in obstetrics It was first used for surgical It was first used for surgical

procedures at the turn of the last procedures at the turn of the last centurycentury

Neuraxial Neuraxial AnesthesiaAnesthesia

AKA Spinal/Epidural AKA Spinal/Epidural AnesthesiaAnesthesia Blunts stress responseBlunts stress response Decreases intra-operative blood lossDecreases intra-operative blood loss Decreases thromboembolic eventsDecreases thromboembolic events Decreases morbidity and mortalityDecreases morbidity and mortality

ANATOMYANATOMY

The SpineThe Spine 33 33

VertebraeVertebrae 7 CERVICAL7 CERVICAL 12 12

THORACICTHORACIC 5 LUMBAR5 LUMBAR 5 SACRAL5 SACRAL 4 4

COCCYGEALCOCCYGEAL

ANATOMYANATOMY

ANATOMYANATOMY

NEURAXIAL ANESTHESIANEURAXIAL ANESTHESIAPHYSIOLOGYPHYSIOLOGY

Autonomic Nervous SystemAutonomic Nervous System Parasympathetic Nervous SystemParasympathetic Nervous System

Craniosacral outflowCraniosacral outflow Sympathetic Nervous System Sympathetic Nervous System

Thoracolumbar outflow Thoracolumbar outflow T1 – L2T1 – L2

Site of Sympathetic BlockadeSite of Sympathetic Blockade

NEURAXIAL ANESTHESIANEURAXIAL ANESTHESIAPHYSIOLOGYPHYSIOLOGY

Cardiovascular System:Cardiovascular System: Decreased PVRDecreased PVR Decreased venous returnDecreased venous return Decreased HRDecreased HR

Profound hypotension in the setting Profound hypotension in the setting of lost compensatory mechanisms of lost compensatory mechanisms with unopposed vagal tone can lead with unopposed vagal tone can lead to cardiac arrest.to cardiac arrest.

NEURAXIAL ANESTHESIANEURAXIAL ANESTHESIAPHYSIOLOGYPHYSIOLOGY

Pulmonary System:Pulmonary System: Decreased vital capacityDecreased vital capacity Decreased accessory muscle toneDecreased accessory muscle tone

GI SystemGI System Increased peristalsisIncreased peristalsis

Urinary SystemUrinary System Urinary retentionUrinary retention

Neuroendocrine SystemNeuroendocrine System Stress response inhibitionStress response inhibition

NEURAXIAL ANESTHESIANEURAXIAL ANESTHESIAPHARAMACOLOGYPHARAMACOLOGY

Neuraxial opioids and local anesthetic Neuraxial opioids and local anesthetic synergysynergy Opioids:Opioids:

FentanylFentanyl MorphineMorphine SufentanilSufentanil

Local anesthetics (epidural)Local anesthetics (epidural) BupivicaineBupivicaine RopivicaineRopivicaine

Local anesthetics (spinal)Local anesthetics (spinal) LidocaineLidocaine TetracaineTetracaine BupivicaineBupivicaine

NEURAXIAL ANESTHESIANEURAXIAL ANESTHESIASPINAL ANESTHESIA-INTRATHECAL SPINAL ANESTHESIA-INTRATHECAL

In use since early 1900In use since early 1900’’ss Reserved for surgeries below umbilicusReserved for surgeries below umbilicus

Hernia repairsHernia repairs Gynecological proceduresGynecological procedures Urological proceduresUrological procedures Lower extremity procedures Lower extremity procedures

(vascular/ortho)(vascular/ortho) ObstetricsObstetrics

NEURAXIAL ANESTHESIANEURAXIAL ANESTHESIAPROCEDUREPROCEDURE

SPINALSPINAL Positioning: lat decub, sittingPositioning: lat decub, sitting Monitoring: BP & HRMonitoring: BP & HR Approach: midline or paramedianApproach: midline or paramedian Sterile techniqueSterile technique Local skin infilterationLocal skin infilteration Passage of spinal needlePassage of spinal needle

+ CSF flow, no heme, no parasthesias+ CSF flow, no heme, no parasthesias Injection of local/opioid mixtureInjection of local/opioid mixture Supine positioning w/ left uterine tiltSupine positioning w/ left uterine tilt VS/block assessmentVS/block assessment

NEURAXIAL ANESTHESIANEURAXIAL ANESTHESIAEPIDURAL ANESTHESIAEPIDURAL ANESTHESIA

1921 – First epidural1921 – First epidural May be utilized as a primary May be utilized as a primary

anestheticanesthetic Adjuvant to general anesthesiaAdjuvant to general anesthesia Post-op pain managementPost-op pain management Best reserved for surgeries below the Best reserved for surgeries below the

umbilicusumbilicus

NEURAXIAL ANESTHESIANEURAXIAL ANESTHESIAEPIDURAL ANESTHESIAEPIDURAL ANESTHESIA

Post-op pain Post-op pain Intra-abdominal proceduresIntra-abdominal procedures Thoracic surgery/traumaThoracic surgery/trauma Vascular proceduresVascular procedures Orthopedics – joint replacementOrthopedics – joint replacement

NEURAXIAL ANESTHESIANEURAXIAL ANESTHESIAPROCEDUREPROCEDURE

EPIDURALEPIDURAL Positioning: lat decub, sittingPositioning: lat decub, sitting Monitoring: BP & HRMonitoring: BP & HR Approach: midlineApproach: midline Sterile techniqueSterile technique Local skin infilterationLocal skin infilteration

NEURAXIAL ANESTHESIANEURAXIAL ANESTHESIAPROCEDUREPROCEDURE

EPIDURALEPIDURAL Passage of epidural needlePassage of epidural needle

+ve LOR to saline/air without +ve LOR to saline/air without CSF/heme/parathesiasCSF/heme/parathesias

Passage of epidural catheter ~ 4–5cmPassage of epidural catheter ~ 4–5cm Test dose : local/epi Test dose : local/epi

R/O intrathecal and intravascular placementR/O intrathecal and intravascular placement Bolus/continuous infusionBolus/continuous infusion

NEURAXIAL ANESTHESIANEURAXIAL ANESTHESIA SPINAL SPINAL

ANESTHESIAANESTHESIA Less time to Less time to

performperform Rapid onsetRapid onset Denser quality of Denser quality of

blockblock

EPIDURAL EPIDURAL ANESTHESIAANESTHESIA Continuous Continuous

anestheticanesthetic Less sympathetic Less sympathetic

blockblock Post-op analgesiaPost-op analgesia

NEURAXIAL ANESTHESIANEURAXIAL ANESTHESIACONTRAINDICATIONSCONTRAINDICATIONS

RELATIVERELATIVE SepsisSepsis Uncooperative patientUncooperative patient Preexiting neurologic Preexiting neurologic

deficitsdeficits Stenotic valvular Stenotic valvular

heart lesionsheart lesions Severe spinal Severe spinal

deformitydeformity

CONTROVERSIALCONTROVERSIAL Prior back surgery at Prior back surgery at

the site of injectionthe site of injection Inability to Inability to

communicate with communicate with patientpatient

Complicated surgeryComplicated surgery Prolonged operationProlonged operation Major blood lossMajor blood loss Maneuvers that Maneuvers that

compromise respirationcompromise respiration

NEURAXIAL ANESTHESIANEURAXIAL ANESTHESIACONTRAINDICATIONSCONTRAINDICATIONS

ABSOLUTEABSOLUTE Infection at siteInfection at site Patient refusalPatient refusal Coagulopathy or bleeding Coagulopathy or bleeding

diathesisdiathesis Severe hypovolemiaSevere hypovolemia Increased ICPIncreased ICP Severe Aortic stenosisSevere Aortic stenosis Severe Mitral StenosisSevere Mitral Stenosis

NEURAXIAL ANESTHESIANEURAXIAL ANESTHESIACOMPLICATIONSCOMPLICATIONS

BackacheBackache Post-Dural Puncture HeadachePost-Dural Puncture Headache Total spinalTotal spinal Neurological injuryNeurological injury InfectionsInfections Spinal/Epidural hematomaSpinal/Epidural hematoma

DisclosureIsmail Mehr MD

I have NO actual or potential conflict of interest in relation to this activity.

I do not have any relevant financial relationships with any commercial interests.