Reader response
Myron Yaster MD
From Jerry Parness MD on the importance of a comma:
Some great PAAD emails last week. HOWEVER, "From Jerry Parness MD, retired on Methadone:".... I am NOT retired on Methadone. I am retired, COMMA, on the subject of Methadone... You are going to get me in trouble with the law!
From Kim Battle
SPA will NOT be distributing naloxone/Narcan at the meeting in Austin. For liability reasons, we do not want to distribute a drug at the meeting. I believe that is why it wasn't done at ASA also.
There will be an "exhibit" table manned by the Disaster Preparedness SIG where they will distribute education materials and teach tourniquet application/hemorrhage control. We will also have a drawing to give away tourniquets.
From Paul Halweg MD Pediatric Anesthesiology - McLane Children’s Medical Center
Many thanks for your commentary & article review. You offer questions that are excellent points for discussion & additional inquiry.
"Is an ultrasound guided pudendal nerve block, or ultrasound guidance for DPN worth the trouble for circumcision?"
In my current practice, the answer to the question is easily a "yes". My typical patient selection for this block is the otherwise healthy patient whom is not a candidate for a caudal - think older child/pre-teen/teenager.
I believe the patient's intra-operative course, PACU recovery, and (home) post-op recovery with ultrasound guided pudendal nerve block/ultrasound guided dorsal penile block illustrate a marked difference. The anesthetic conducted (GA + 100mcg of fentanyl & 1-2 mg of hydromorphone) when a surgeon performs a post-procedure penile/ring block versus anesthetic conducted when I perform a penile block (2 mL or less of 0.5% bupivacaine + dexmedetomidine and zero to minimal IV opiate) is night and day.
I have performed ultrasound guided pudendal nerve blocks for both circumcision & hypospadias repair/revision. Anecdotally, I can report ultrasound guided pudendal nerve blocks are excellent for these surgeries. This bilateral block takes me about 20min to perform, mainly to due to patient positioning needs to facilitate block placement.
I currently utilize ultrasound guided dorsal penile blocks for circumcision & the occasional hypospadias repair/revision. Anecdotally, I can report ultrasound guided dorsal penile blocks have been efficacious for both circumcision & hypospadias surgery. This bilateral block takes me about 10min to perform.
Yes, circumcision pain has been managed without these "fancy" techniques for decades; however, I would challenge the assertion that circumcision pain in the older child/pre-teen/teenager patient group has been managed relatively effectively.
Re: Fabian's commentary "...it is routine for the surgeon to do a dorsal penile nerve block using the traditional landmark approach prior to circumcision. However, the efficacy is far from perfect."
--I agree. The surgeon usually places this block at the conclusion of the surgery, and the proverbial pre-emptive analgesia "ship has sailed". This block's efficacy is usually quite suboptimal.
"This recent paper...claiming equivalence of DPN block and pudendal."
--Given my anecdotal experience - I agree that ultrasound guided pudendal nerve blocks & ultrasound guided dorsal penile blocks seem to be equivalent.
From Lynne Maxwell MD, retired and member of the PAAD’s executive council and frequent contributor
My study was not the first to show that PNB was effective to mitigate circumcision pain. Previous studies showed lower HR, BP, and crying time for PNB during newborn circumcision. The innovation of my study was that a new technology, pulse oximetry, was used to show that crying could be correlated with greater breath holding and associated desaturation in the babies who did not have PNB (a surrogate marker of pain).
Although dorsal PNB may spare the ventral side of the penis, studies have demonstrated that adding a subcutaneous ring block at the ventral base of the penis bilaterally improves efficacy.
More from Paul Halweg MD Pediatric Anesthesiology - McLane Children’s Medical Center
To your question: "Does bradycardia in the absence of hypotension need to be treated?"
My answer: It depends. I keep in mind heart rate x stroke volume = cardiac output, along with the three components of stroke volume - preload, afterload & contractility.
All other things being equal, I assume cardiac myocyte maturation at around 4-6 years of age. (If someone has a go-to resource for this data, I would appreciate a reference)
If conducting an inhaled induction, then I perform the induction in a graded manner with sevoflurane at no greater than 5%, along with nitrous oxide. My goal is to attain induction as smoothly as possible, neither too fast nor too slow while maintaining sinus rhythm.
Presuming a neonate or infant, and the heart rhythm transitions from sinus to a junctional rhythm (junctional escape rhythm) with the likely drop in cardiac output, then I am more likely to treat bradycardia with epinephrine, atropine, or glycopyrrolate. This patient population is heart rate dependent for cardiac output, with little to no ability to modify components of stroke volume, namely contractility. I am also sensitized to the tendency for neonate/infant patient's with trisomy 21 to rapidly progress from sinus rhythm to junctional rhythm to heart block to cardiac arrest.
Presuming an older child (4+ yrs of age), and the heart rhythm transitions from sinus to a junctional rhythm (junctional escape rhythm), then I am more likely to wait, carefully decrease the anesthetic depth and await the patient's return to a sinus rhythm. If this is unsuccessful or I encounter a repeat junctional rhythm episode, then I treat with epinephrine, atropine, or glycopyrrolate. In my judgement, this patient population has some ability to modify the components of stroke volume, namely contractility.