Common Peri-Operative Medications

Respiratory Depression Sarah is a 35 year old female, who underwent GI surgery this morning. She received 5 mg of morphine IV in recovery and is now on your unit. Twenty minutes after admission, you check on her to find that she is unresponsive to verbal stimuli. Her vitals are normal but breathing is 6 breaths per minute. What do you do?

Treatment of Narcotic Overdose Try to awaken pt Recount RR If conts to be low: Call MD(if no standing order) naloxone hydrochloride (Narcan) Repeat dosages as ordered

Naloxone hydrochloride Trade Name - Narcan Reverses all effects of narcotics How?

Atropine Now Sarah is fully awake and breathing normally. But she complains to you that her mouth is very dry and she is thirsty. Providing that she isn’t dehydrated, what explanation would you give to Sarah?.

She was given Atropine prior to surgery It causes drying of the mouth How to treat: Mouth swabs Ice chips or wet cloth for mucus membranes

Atropine An anticholinergic drug Blocks effect of acetylcholine (ACH)

Acetylcholine Excreted by the Parasympathetic system The caretaker system in charge when all is quiet: Heart beats slowly GI tract is active Bladder constricts Pupils constrict Digestive juices  (think of saliva)

ACH = cholinergic. Drugs that prevent ACH from doing it’s work are called “anticholinergics.” (Atropine)

These drugs reverse the effect of ACH

Everyday functions are blocked: Heart beats faster

GI tract slows down Bladder relaxes

Pupils dilate Digestive juices 

Why Atropine Pre-Op? All of these effects help a patient to better tolerate surgery: prevents slowing of heart dries secretions interferes with voiding, slows peristalsis, dilates bronchi

Case Study - Promethazine Hydrochloride (Phenergan) Sarah appreciates all your explanations so far. But she has one more thing to tell you – she is feeling nauseated and it’s gotten worse since an hour ago. Could she please have something for the nausea?

N & V triggered by: GI tract sends “irritation” messages to the “Vomiting Center” “dopamine” transmits the “vomit stimulus” in the vomiting center of the medulla. Must block dopamine to decrease N & V.

Phenergan: Blocks release of dopamine Is also an antihistamine – blocks H2 receptors in the stomach Result: __________ Induces light sleep Decreases anxiety Stims gastric acid

Other Antiemetics Compazine (blocks dopamine) Metochlopramide - Reglan

Zofran (selective serotonin receptor antagonist) Serotonin released from wall of small intestine Stimulates vagal nerve Initiates vomiting reflex Used to prevent N/V in post-op patients

Diazepam - Valium Tory is a 32 year old female undergoing surgery today for a breast biopsy. When you enter the room with her pre-op diazepam, 5 mg, po, she states, “My mother was addicted to Valium, I’d rather not take it.” What should be your response?

a.You are concerned about becoming addicted to Valium. b.Don’t be silly. Just because your mother was addicted you think you’ll become addicted? c.You can’t become addicted to Valium. d.We really don’t have time to talk about this.

Diazepam - Valium Benzodiazepine family Used as a sedative or an antianxiety agent, status epilepticus, muscle relaxation Also used for induction of anesthesia

Bethanechol - Urecholine Mr. Jones has undergone surgery for removal of kidney stone today. As he returns from surgery you note on the doctor’s orders an order for bethanechol. Why would the doctor order this medication for Mr. Jones?

Bethanechol (Urecholine) It increases ACH in the body. Has the opposite effect of Atropine

Bethanechol For urinary retention At normal doses, can cause excessive salivation, increased secretion of gastric acid, abdominal cramps and diarrhea

Meperidine - Demerol Narcotic used for pain Side effects: Respiratory depression Orthostatic hypotension Cough suppresant Constipation Urinary retention Epigastric distress ICP elevation