Latest posts by the anesthesia consultant (see all)
- DO DOCTORS EVER RIDE IN AMBULANCES? - 11 Jul 2019
- REGARDING THE FRENCH ANESTHESIOLOGIST ACCUSED OF MURDER - 1 Jul 2019
- INTRAVENOUS CAFFEINE FOLLOWING GENERAL ANESTHESIA - 18 Jun 2019
Clinical Case of the Month: A 5-year-old boy is scheduled for general anesthesia for a cochlear implant. On your pre-operative phone call to the mother, she tells you that after the same surgery on the other ear, the child was severely agitated in the Recovery Room. The last anesthesiologist told her that agitation was a common side effect for the sevoflurane anesthetic that was used. What will you do?
Discussion: How about this plan: You obtain the old anesthesia record, duplicate the technique exactly, and give earplugs to everyone within ten yards of the Recovery Room? Don’t buy it? Read on.
Before you begin, a colleague says, “Who cares about crying? As long as the anesthetic care is safe, crying in the PACU is no big deal. It’s a sign of an adequate airway.” He continues: “Why, I went on an Interplast trip fixing cleft palates in South America, and all the kids screamed in the Recovery Room. They all survived.”
I’ve got news for him — a screaming child in the Recovery Room is a problem for several people: the nurse, the mother of the child (she’s freaking out herself), the attending anesthesiologist (who, by inference, looks like he doesn’t know how to finish an anesthetic), and every other PACU patient within earshot. I’d submit that the goals of a 21st Century anesthetic go beyond safety — patients or their families feel entitled to wake up as pain-free, nausea-free, and side-effect-free as possible.
Sevoflurane was introduced in Japan in the late 1980’s and in the United States in the 1990’s (Miller’s Anesthesia, 2005, p. 18). Because of its low solubility, sevoflurane represented a significant advance over isoflurane, which dominated the inhaled anesthetic market prior to that time. In addition to its low solubility, sevoflurane was less pungent than isoflurane and could be used instead of halothane for inhalational induction in children. As well, sevoflurane had a lower incidence of cardiac arrhythmias than halothane. These properties made sevoflurane the drug of choice for inhalation induction in children (Johannesson GP, Acta Anaesthesiol Scand. 1995 May;39(4):546-50).
Soon after its introduction into clinical practice, reports of sevoflurane and post-operative agitation and delirium in preschool patients began to appear in the anesthesia literature. The described agitation was unrelated to pain, was inversely related to age, and was most frequent in children 5 years of age or younger. (Miller’s Anesthesia, 2005, p. 2373). Emergence delirium with sevoflurane exceeded the rate of emergence delirium with halothane. Aono reported a 40% incidence of delirium during recovery in preschool boys aged 3 – 5 years old who underwent urologic surgery under sevoflurane, vs. a 10% incidence of delirium for those who were anesthetized with halothane (Anesthesiology, 1997 Dec;87(6):1298-300).
A variety of remedies appeared in the peer-reviewed literature over the ensuing years. A complete discussion of all reported techniques is beyond the scope of this short column. I refer you to PubMed with the keywords sevoflurane, agitation, where you’ll find multiple references to support multiple techniques. Statistical significance was obtained in controlled studies with the following techniques either before or after sevoflurane induction: use of oral midazolam prior to induction; use of a single dose of fentanyl 1 mcg/kg ten minutes prior to emergence; conversion to propofol infusion anesthesia after induction; conversion to isoflurane anesthesia after induction; conversion to desflurane anesthesia after induction; use of IV dexmedetomidine 0.3 – 0.5 mcg/kg after induction; use of PO clonidine premedication 4 mcg/kg before induction; or use of IV clonidine 2 mcg/kg immediately after induction.
I polled my private practice Stanford Adjunct Clinical Faculty colleagues on their preferred methods to minimize pediatric emergence delirium, and three strategies prevailed: 1) the use of heavy midazolam premedication (up to .8 mg/kg); 2) the use of titrated doses of intravenous fentanyl or meperidine prior to emergence; and 3) discontinuance of sevoflurane after inhalation induction — instead substituting isoflurane or propofol for maintenance anesthesia. No one used dexmedetomidine or clonidine.
Let’s return to your 5-year-old patient. You decide to utilize all three options described in the previous paragraph. You begin with the oral midazolam premedication 20 minutes prior to induction. (Because the duration of this surgery is estimated to be 90 minutes, you realize that most of the effect of the midazolam premed will be dissipated at the time of emergence.) After an uneventful sevoflurane mask induction, you place an I.V. and intubate the trachea. At this point you turn off the sevo and switch to isoflurane. Cochlear implant surgery involves drilling into the skull, and despite use of local anesthesia by the surgeon, you can anticipate post-operative pain. It seems prudent to use a narcotic to treat both pain and delirium. At the conclusion of the anesthetic, you administer doses of 5 mg of meperidine, titrated to the child’s respiratory rate. After extubation, you supplement with additional narcotic as needed to affect comfort and tranquility. Because both the surgery and the anesthetic technique may stimulate post-operative nausea or vomiting, you administer doses of I.V. ondansetron and metoclopramide for nausea prophylaxis. You request the mother sit at the bedside in the PACU as soon as the child begins to reawaken, as a humane non-pharmacologic method of easing the child’s emotional discomfort .
There are no trophies given for rapid wake-ups in the pediatric PACU. Your technique produces a gradual calm emergence characterized by safe maintenance of the airway and a relaxed, comfortable child. The 5-year-old’s mother is thrilled with the improvement over the last anesthetic, and the PACU nurses respect that you care about the quality of your patient’s wake-up.
Published in September 2017: The second edition of THE DOCTOR AND MR. DYLAN, Dr. Novak’s debut novel, a medical-legal mystery which blends the science and practice of anesthesiology with unforgettable characters, a page-turning plot, and the legacy of Nobel Prize winner Bob Dylan.
In this debut thriller, tragedies strike an anesthesiologist as he tries to start a new life with his son.
Dr. Nico Antone, an anesthesiologist at Stanford University, is married to Alexandra, a high-powered real estate agent obsessed with money. Their son, Johnny, an 11th-grader with immense potential, struggles to get the grades he’ll need to attend an Ivy League college. After a screaming match with Alexandra, Nico moves himself and Johnny from Palo Alto, California, to his frozen childhood home of Hibbing, Minnesota. The move should help Johnny improve his grades and thus seem more attractive to universities, but Nico loves the freedom from his wife, too. Hibbing also happens to be the hometown of music icon Bob Dylan. Joining the hospital staff, Nico runs afoul of a grouchy nurse anesthetist calling himself Bobby Dylan, who plays Dylan songs twice a week in a bar called Heaven’s Door. As Nico and Johnny settle in, their lives turn around; they even start dating the gorgeous mother/daughter pair of Lena and Echo Johnson. However, when Johnny accidentally impregnates Echo, the lives of the Hibbing transplants start to implode. In true page-turner fashion, first-time novelist Novak gets started by killing soulless Alexandra, which accelerates the downfall of his underdog protagonist now accused of murder. Dialogue is pitch-perfect, and the insults hurled between Nico and his wife are as hilarious as they are hurtful: “Are you my husband, Nico? Or my dependent?” The author’s medical expertise proves central to the plot, and there are a few grisly moments, as when “dark blood percolated” from a patient’s nostrils “like coffee grounds.” Bob Dylan details add quirkiness to what might otherwise be a chilly revenge tale; we’re told, for instance, that Dylan taught “every singer with a less-than-perfect voice…how to sneer and twist off syllables.” Courtroom scenes toward the end crackle with energy, though one scene involving a snowmobile ties up a certain plot thread too neatly. By the end, Nico has rolled with a great many punches.
Nuanced characterization and crafty details help this debut soar.
Click on the image below to reach the Amazon link to The Doctor and Mr. Dylan:
Learn more about Rick Novak’s fiction writing at ricknovak.com by clicking on the picture below: