Anesthetic Agents J. Michael Semenza, II, MD Island Medical Consultants October 15, 2016

Objectives Inhaled Anesthetics Intravenous Anesthetics Neuromuscular Blocking Drugs

Objectives Inhaled Anesthetics History Nitrous Oxide Isoflurane Sevoflurane Desflurane Intravenous Anesthetics Neuromuscular Blocking Drugs

PACU Patient 35 F with a history of asthma presents with a renal stone and undergoes a cystoscopy with laser lithotripsy for stone removal Anesthetic General anesthetic with an LMA Which inhalational agent would you use?

Inhaled Anesthetics – Ideal Qualities Quick onset/offset Not flammable No organ toxicity Does not promote nausea and vomiting Low cost

Nitrous Oxide - History One of first inhaled anesthetics Joseph Priestly Synthesized in 1772 Sir Humphry Davy “Laughing gas” Horace Wells “Painless dentistry”

Nitrous Oxide Weak general anesthetic and generally not used as a single agent Used as a carrier gas with oxygen in combination with more potent inhalational gases for surgical anesthesia In dentistry, commonly used as a single agent with oxygen for partial sedation. Mask induction for pediatric patients

Nitrous Oxide – Adverse Effects Contraindications Pneumothorax Air embolism Pregnancy Interferes with vitamin B12 and folate metabolism Nausea and vomiting

Isoflurane Introduced into clinical practice in 1980s and widely used clinically Not associated with cardiac dysrhythmias Associated with less toxicity than predecessors Delayed recovery from anesthesia

Sevoflurane Use started in the 1990s Pediatric patients Advantages Rapid onset and rapid recovery of anesthesia Not as pungent as Desflurane Bronchodilator

Desflurane Advantages Rapid onset and recovery of anesthesia useful for outpatient procedures One of the least metabolized to toxic byproducts Disadvantages $$$ Pungent and irritating to the airway more coughing, laryngospasm Significant increase in the BP and HR

PACU Patient 35 F with a history of asthma presents with a renal stone and undergoes a cystoscopy with laser lithotripsy for stone removal Anesthetic General anesthetic with an LMA Which inhalational agent would you use?

PACU Patient 35 F with a history of asthma presents with a renal stone and undergoes a cystoscopy with laser lithotripsy for stone removal Anesthetic General anesthetic with an LMA Which inhalational agent would you use? Sevoflurane, although any agent can be used.

Objectives Inhaled Anesthetics Intravenous Anesthetics Propofol Ketamine Neuromuscular Blocking Drugs

Case Presentation Enhanced Recovery After Surgery (ERAS) Reduction in complications and hospital stay Non opioid analgesia 55 yo M with a history of colon cancer presents for a robotic assisted partial colectomy. General anesthesia What infusion can be run to decrease/eliminate opioid usage during surgery?

Propofol Indications Rapid induction of anesthesia Sedation in the operating room Sedation in intensive care settings

Propofol - Pharmacodynamics Central Nervous System Hypnotic No analgesic properties Cardiovascular System Large decrease in systemic BP Respiratory System Respiratory depressant Other Effects Antiemetic Pain on injection

Propofol

Ketamine PCP derivative Introduced into clinical practice in 1965 Produces significant analgesia Primary Uses Induction and maintenance for anesthesia Sedation or general anesthesia in children Chronic pain management

Ketamine - Pharmacodynamics MOA NMDA receptor antagonist Central Nervous System Increases intracranial pressure Cardiovascular System Significant increase in BP, HR and CO Respiratory System NO significant respiratory depression

Ketamine – Disadvantages Unpleasant Emergence Reactions Vivid colorful dreams Hallucinations Out-of-body experiences Distorted visual, tactile and auditory sensitivity Lesser incidence in children

Case Presentation Enhanced Recovery After Surgery (ERAS) Reduction in complications and hospital stay Non opioid analgesia 55 yo M with a history of colon cancer presents for a robotic assisted partial colectomy. General anesthesia What infusion can be run to decrease/eliminate opioid usage during surgery?

Case Presentation Enhanced Recovery After Surgery (ERAS) Reduction in complications and hospital stay Non opioid analgesia 55 yo M with a history of colon cancer presents for a robotic assisted partial colectomy. General anesthesia What infusion can be run to decrease/eliminate opioid usage during surgery? Ketamine

Objectives Inhaled Anesthetics Intravenous Anesthetics Neuromuscular Blocking Drugs (NMBD) Succinylcholine Rocuronium Cisatracurium

Case Presentation 55 yo male with a history of ESRD on hemodialysis presents for an emergent laparoscopic appendectomy with a full stomach. What labs are important in pre-op? Why? What neuromuscular blocking drugs will be used for intubation and for maintenance?

Neuromuscular Blocking Drugs – Clinical Uses Facilitate tracheal intubation Provide optimal surgical conditions Facilitate mechanical ventilation

Neuromuscular Blocking Drugs – Choice Speed of onset Duration of action Route of elimination Side effects

Neuromuscular Blocking Drugs

DepolarizingNondepolarizing

Neuromuscular Blocking Drugs Depolarizing Nondepolarizing

Neuromuscular Blocking Drugs Classification of Neuromuscular Blocking Drugs Depolarizing (Rapid Onset and Ultrashort-Acting) Succinylcholine Nondepolarizing Long-Acting Pancuronium Intermediate-Acting Vecuronium Rocuronium Cisatracurium Short-Acting Mivacurium

Succinylcholine Only depolarizing NMBD used clinically Structurally similar to acetylcholine Very short duration of action Metabolized very quickly by the enzyme plasma cholinesterase Useful drug when muscle relaxation is needed for only a short time

Succinylcholine – Adverse Effects Cardiac dysrhythmias Sinus bradycardia Junctional Rhythm Sinus arrest Fasciculations Hyperkalemia Myalgia Myoglobinuria Increased intraocular pressure Increased intragastric pressure Trismus

Rocuronium The most rapid onset time for non-depolarizing NMBD Minimal cardiovascular effects Intermediate acting non- depolarizing NMBD

Cisatracurium Not dependent on the kidney for its elimination Hofmann elimination Patients with renal or hepatic failure Intermediate acting non- depolarizing NMBD

Case Presentation 55 yo male with a history of ESRD on hemodialysis presents for an emergent laparoscopic appendectomy with a full stomach. What labs are important in pre-op? Why? What neuromuscular blocking drugs will be used for intubation and for maintenance?

Case Presentation 55 yo male with a history of ESRD on hemodialysis presents for an emergent laparoscopic appendectomy with a full stomach. What labs are important in pre-op? Why? Potassium What neuromuscular blocking drugs will be used for intubation and for maintenance? Succinylcholine for rapid sequence intubation Cisatracurium for maintenance

The End Thank you

References Aladin2 Cassettes. GE Healthcare. Retrieved October 1, 2016 from Almeida. (2012) Nitrous oxide: are you having a laugh? Retrieved October 1, 2016 from Fox, S. (2013). Special Ketamine. Pediatric EM Morsels. Retrieved October 1, 2016 from Harmon, K. (2011). Michael Jackson. Scientific American. What is Propofol – and How Could It Have Killed Michael Jackson. Retrieved October 1, 2016 from michael-jackson-doctor/ michael-jackson-doctor/ Miller, R.D. (2010); Miller’s Anesthesia. 7 th ed., Philadelphia, PA: Churchill Livingstone/Elsevier. Nimbex. Southern Anesthesia Surgical. Retrieved October 2, 2016 from Cisatracurium-Besylate-2mg-ml-10ml-Multiple-Dose-Vial/ https:// Cisatracurium-Besylate-2mg-ml-10ml-Multiple-Dose-Vial/ Stoelting, R.K., Miller, R.D.; (2012) Basics of Anesthesia. 6th ed., Philadelphia, PA: Churchill Livingstone Publishing Company. Succinylcholine. Pharmedium. Retrieved October 3, 2016 from