ASK
THE EXPERTS: PEDIATRICS
What are sedative syrup drugs used in children? What protocol do you advise for premedication in pediatric anesthesia? —dr_a_ahmed@hotmail.com
Dr.
Charles Coté responds:
The most common premedication of pediatric patients in the US is oral midazolam (see articles by Z. Kain [1]). Generally until the commercial formulation becomes available again, we mix the intravenous formulation with a little bit of cherry flavored syrup form our hospital pharmacy. The usual dose is 0.25-0.33 mg/kg with a maximum dose of 15 mg. Usually this takes about 10-15 minutes to work with minimal effects upon respirations. If a great degree of anxiety is present we can increase the dose all the way to 1 mg/kg but this would be unusual. We do not combine it with other sedating medications unless there is a really upset child who has previously failed this regimen. In that situation we might add atropine 0.02 mg/kg plus ketamine 2-4 mg/kg all combined and given orally. In this circumstance the child must be carefully observed with pulse oximetry. This should not be given to children with abnormal airways.
Reference:
- 1. Kain ZN, Hofstadter MB, Mayes LC, Krivutza DM, Alexander G, Wang SM, Reznick JS. Midazolam: effects on amnesia and anxiety in children. Anesthesiology 2000 Sep;93(3):676-84. Click here for abstract.
What are the current recommendations regarding the placement of cuffed versus uncuffed endotracheal tubes in children under 5 years of age? —pxg9@hotmail.com
Dr.
Charles Coté responds:
Generally over the years the usual practice has been to use uncuffed
endotracheal tubes in children less than about 10 years of age because we
know that the narrowest portion of the airway is in the subglottic region
at the level of the cricoid cartilage. Using an uncuffed tube and checking
for a leak between 20 and 30 cm water peak inflation pressure allowed for the
insertion of a larger diameter endotracheal tube than if we used a cuffed
tube. This was important for children allowed to breath spontaneously.
Now with the increasing use of controlled ventilation this is less of a
concern. Even with a cuffed tube it is important to check for a leak
around the uninflated cuff so as to minimize the potential for subglottic
injury and edema. Recently there have been several publications advocating
cuffed endotracheal tubes even in infants. The reasoning is that by using
a smaller tube one can compensate for any leak with inflation of the cuff
and thereby avoiding having to change the tube. Both arguments are valid
as long as one pays careful attention to leak around the cuff is one
chooses to use a cuffed tube. I would not use a cuffed tube in a child
less than one year of age because the size 3 cuffed tube has quite a large
external diameter. My practice is still to use uncuffed tubes in children
below 8 years of age unless I place for example a 5.5 uncuffed tube and
there is a leak at a very low inflation pressure , e.g. 10 cm water. In
that case I would change it to a 5.0 cuffed tube and inflate the cuff just
enough to allow adequate inflation pressures. Also it is important to
check the cuff periodically if using nitrous oxide since the nitrous oxide
can diffuse into the cuff and cause excessive cuff pressure which then
cause mucosal injury and the potential for subglottic swelling.
What do you think of the practice of carrying a small pediatric patient in your arms to the operating theater? —nickalgarra@rocketmail.com
Dr. Charles Coté responds:
I think that this is a wonderful practice for the small babies who really just want to be held...we do this daily but the concern some have is what if you slip and fall!! I guess a bed can tip over also!
question —xxx
Dr.
xxxx responds:
answer
What are the recommendations for the post-op management of a non-premature infant( less than two months of age) undergoing a minor procedure? Should these children be observed and monitored overnight after their surgery? —stranicknc@aol.com
Dr. Charles Coté responds:
There are no very good data on what to do with this population. We know that there are sporadic case reports of apnea in full term babies and that at least some of these may be children with Sudden Infant Death Syndrome (SIDS)....these generally manifest as periodic breathing and/or apnea in recovery. Periodic breathing is very abnormal in a full term baby and is a red flag for continued and prolonged observation. Many children's hospital have a policy to admit children overnight when full term and less than 30 days of age but the reality is we do not know if this is good practice or a waste of money.
What are the risks of being under anesthesia for a 6 or 7 hour time
period? This is for a 12 year old female in otherwise good health who
will undergo an anterior/posterior spinal fusion. —Heidi Wigand-Nicelyu
Dr.
Charles Coté responds:
For this particular
case and operation it is difficult to provide a complete answer without
knowing the underlying causes of the scoliosis. Anesthetic risk is
generally proportional to the severity of underlying medical conditions.
There is really no additional risk for anesthesia related to time,
rather the risk is primarily related to the potential for rapid and
massive blood loss, injury to the spinal cord during insertion of
the supporting hardware and other risks primarily surgical in origin.
I personally have anesthetized an adult for as long as 46 hours and
even with that extreme duration the only issue was minor depression
of white bloodcells. That is not an issue for an 8 hour procedure.
I would assure thisperson that there is no special risk other than
those described above.
We are interested in starting to use intra-nasal fentanyl 2 micrograms/kg
for our BMT surgeries. I have recently been to a talk where this procedure
has been utilized. I have been unable to find any thing published on
using fentanyl in this manner. What is your experience with this technique,
and or is there any published data on this technique?—karlk@milwpc.com
Dr.
Charles Coté responds:
There are a large
number of papers that have described intranasal administration of a
variety of medications both as a means of providing a premedication
and as a means of providing analgesia postoperatively. [1-6] Sufentanil
1-3 micrograms/kg has been described for premedication;[2;3] several
patients have developed desaturation and higher doses my result in chest
wall rigidity. Another paper described the use of intranasal butorphanol;
a dose of 25 micrograms/kg was felt to be an effective post myringotomy
analgesic.4 The nasal route of drug administration is certainly reasonable,
however, only drugs that are free of neurotoxicity (and their preservatives)
should be considered [7] since there is a direct connection between
the nasal mucosa and the central nervous system along the neurovascular
connections of the olfactory nerve. [8]Nasal fentanyl has been used
in adult patients as an alternative to PCA;[9;10] there is no reason
to assume that it would not be effective for minor postoperative pain
when administered in low doses.
References:
- Walbergh EJ,
Wills RJ, Eckhert J: Plasma concentrations of midazolam in children
following intranasal administration. Anesthesiology 1991;
74: 233-5
Click here for abstract
- Henderson JM,
Brodsky DA, Fisher DM, Brett CM, Hertzka RE: Pre-induction of anesthesia
in pediatric patients with nasally administered sufentanil. Anesthesiology
1988; 68: 671-5
Click here for abstract
- Karl HW, Keifer
AT, Rosenberger JL, Larach MG, Ruffle JM: Comparison of the safety
and efficacy of intranasal midazolam or sufentanil for preinduction
of anesthesia in pediatric patients. Anesthesiology 1992;
76: 209-15
Click
here for abstract
- Bennie RE,
Boehringer LA, Dierdorf SF, Hanna MP, Means LJ: Transnasal butorphanol
is effective for postoperative pain relief in children undergoing
myringotomy. Anesthesiology 1998; 89: 385-90
Click
here for abstract
- Tobias JD,
Rasmussen GE: Transnasal butorphanol for postoperative analgesia
following paediatric surgery in a Third World country. Paediatric
Anaesthesia 1995; 5: 63-6
- Malinovsky
JM, Servin F, Cozian A, Lepage JY, Pinaud M: Ketamine and norketamine
plasma concentrations after I.V., nasal and rectal administration
in children. Br J Anaesth 1996; 77: 203-7
- Malinovsky
JM, Lepage JY, Cozian A, Mussini JM, Pinaudt M, Souron R: Is ketamine
or its preservative responsible for neurotoxicity in the rabbit?
Anesthesiology 1993; 78: 109-15
Click
here for abstract
- Committee on
Drugs American Academy of Pediatrics: Alternate routes of drug administration
- advantages and disadvantages. Pediatrics 1997; 100: 143-52
- Toussaint S,
Maidl J, Schwagmeier R, Striebel HW: Patient-controlled intranasal
analgesia: effective alternative to intravenous PCA for postoperative
pain relief. Can J Anaesth 2000; 47: 299-302
Click
here for abstract
- Zeppetella
G: An assessment of the safety, efficacy, and acceptability of intranasal
fentanyl citrate in the management of cancer-related breakthrough
pain: a pilot study. J Pain Symptom Manage. 2000; 20: 253-8
I do conscious sedation on a regular basis. I use midazolam as a bolus I.V.
injection and follow with a continuous infusion of a mixture of diprivan and
rapifen. I have no problems with this regimen in adult patients. Paediatric
patients on the other hand, seem to get quite agitated at times, despite optimal
oxygenation. I have heard about using ketalar (ketamine) instead. Can you offer
a regimen for use in children? What about the hallucinations known to be a side-effect?
—
Stan West, MBChB, PhD stan.west@webmail.co.za
Dr.
Charles Coté responds:
I guess I would answer
this by first stating that "conscious sedation" is an oxymoron for children
since by definition it means that the child is responsive to verbal command.
The combination of drugs described would not produce that state, and it would
be very difficult to achieve that state . The ASA has decided to use the phrase
"sedation/ analgesia" which is more precise than "conscious sedation". The
new JCAHO regulations now have mild sedation/analgesia, moderate sedation
analgesia and deep sedation analgesia. The first two levels are equivalent
to anxiolysis and sedation/analgesia.
Regarding the drugs -
ketamine in very low doses (0.25-0.5 mg/kg every 5 - 10 minutes) added to
the propofol might work reasonably well but I am not sure for what procedures
this is indicated. Titration of drug to effect, proper monitoring, proper
recovery and the use of atropine to prevent secretions are essential if ketamine
is to be used. You may have to give an initial loading dose of 1-2 mg/kg then
follow with titration of the much smaller doses.
Without knowing more regarding
possible contraindications, however, I cannot fully answer this question.
I have heard that
in children when, in need, a reliable and safe place for administration
of succinylcholine IM is intralingual. I have not found anything written
about this. Would you like to comment? —Andreas Ekman
M.D.
Dr. Charles Coté responds:
There are only a couple of papers describing this route of administration
for succinylcholine It appears that drug uptake is much dependent upon
where it is administered. Drugs administered in the leg (vastus lateralis)
are more slowly absorbed than drugs administered in the deltoid. In
addition drugs administered in the tongue are more rapidly absorbed
than in regular muscle tissue. There is however the potential for intra-oral
bleeding which could compound a difficult airway problem but I have
no personal experience with this route of administration. It would be
important to combine atropine with the succinylcholine so as to avoid
potential bradycardia. One paper has reported "submental"
administration, i.e., external puncture in the submental area into the
tongue. Although this is a blind technique it avoids the need to remove
the face mask from the face or to pry the mouth open in an emergent
situation [1-7].
References:
-
Liu
LM, DeCook TH, Goudsouzian NG, Ryan JF, Liu PL: Dose response to intramuscular
succinylcholine in children. Anesthesiology 1981; 55: 599-602.
-
Moore
GP, Pace SA, Busby W: Comparison of intraosseous, intramuscular, and
intravenous administration of succinylcholine. Pediatr Emerg Care
1989; 5: 209-10
-
Evans
EF, Proctor JD, Fratkin MJ, Velandia J, Wasserman AJ: Blood flow in
muscle groups and drug absorption. Clin Pharmacol Ther 1975;
17: 44-7
-
Mazze
RI, Dunbar RW: Intralingual succinylcholine administration in
children: an alternative to intravenous and intramuscular routes?
Anesth Analg 1968; 47: 605-15
-
Redden
RJ, Miller M, Campbell RL: Submental administration of
succinylcholine in children. Anesth Prog 1990; 37: 296-300
-
Reynolds
LM, Lau M, Brown R, Luks A, Fisher DM: Intramuscular
rocuronium in infants and children. Dose-ranging and tracheal intubating
conditions. Anesthesiology 1996; 85: 231-9
-
Sullivan
KJ, Berman LS, Koska J, Goodwin SR, Setzer N, White SE,
Graves SA, Nall AV: Intramuscular atropine sulfate in children: comparison
of injection sites. Anesth Analg 1997; 84: 54-8
I
am working as an anesthesiologist and intensivist in pediatric cardiac surgery.
In Germany it is quite common to use muscle relaxants such as vecuronium
to prevent pulmonary hypertensive reaction after operations with cardiopulmonary
bypass. Is this reasonable, and do you know of any pharmacological basis
that explains how this works? As far as I know, the muscle relaxants don’t
have any effect on vegetive ganglia in therapeutic doses. Do you know of
any literature on this subject?
—Katharina Walter
Dr. Douglas Coursin responds:
I am not familiar with this as a primary approach to management of pulmonary
hypertension or control of pulmonary artery pressure (PAP). In addition,
after a review of the literature (extensive Medline search) and discussion
with some respected colleagues, I failed to find a primary reference that
would suggest the use of vecuronium or other neuromuscular blocker (NMB)
has a direct effect on the pulmonary vasculature or results in PA vasodilatation.
NMBs may have secondary effects, if the infant or child was shivering or
had an uncompensated acidosis or inadequate ventilation (i.e. low Pa02).
Then chemical paralysis and more effective gas exchange would potentially
indirectly help lower PAPs. If the child was hypervolemic or in heart failure,
venous capacitance could theoretically increase with a paralysis induced
decrease in peripheral muscle tone and venous pump.
There does not appear to be any direct effect of vecuronium on the autonomic
nervous system. Finally, I assume that appropriate sedation and analgesia
are administered along with an NMB and one can only speculate on the role
polypharmacology may have on pulmonary artery pressures.
During the
recovery phase (PACU), is it required to monitor the BP of children <2
yrs? Does the BP accurately measure the child's circulatory status when
he/she is resisting and crying because the BP cuff scares them? —Eric
Watson
Dr. Coté Responds:
Most pediatric hospitals routinely measure blood pressure in children of all ages. We have found that measuring the blood pressure on the calf is less threatening than the arm and it is frequently easier to keep the leg still. If an automated device fails, then blood pressure by palpation is sufficient. Obviously if a child is vigorous and active there is little likelihood that there is a problem. However, if a child has had a procedure where there was blood loss or recently received a drug which could cause an adverse response (allergic reaction), then measurement of blood pressure should be at least attempted and, if unsuccessful, then the reason should be documented. Blood pressure measurements in children are just as important as in adults, but the frequency of an abnormal number is much lower than in adults.
I have been using D5 infusions for the past 10 years in pediatric surgery until very recently when someone told me that glucose is causing some brain and CNS impairment. Can you update me or elaborate on the dangers of glucose, especially in pediatric patients? Also, in general, what can glucose do to the body beside causing hyperglycemia —Joe Haleyalmang, Yap Medical Staff
Dr. Coté Responds:
Hyperglycemia, i.e. a glucose of > 200 mg/dL, has been associated with a larger area of brain injury following an hypoxic event in animal models as well as in outcome data from resuscitation of children. [1-3] These investigations suggest that if a child should suffer a severe hypoxic event, the outcome may be better if the child's blood sugar was less than 200 mg/dL at the time of the event. Hypoglycemia is a rare event in healthy children presenting for elective surgery. Hypoglycemia is even less likely with the liberalized approach to preoperative fasting, i.e. no milk, solid, or breast milk for the standard periods of time, but unlimited clear fluids such as apple juice for up to 2-3 hours prior to anesthetic induction. [4] Most pediatric anesthesiologist no longer routinely use glucose containing solutions unless there is a specific indication, e.g. a severely malnourished child with reduced glucose reserves, neonates, patients receiving intravenous alimentation. This avoids the bolus administration of glucose at the beginning of an anesthetic when one is attempting to replace fasting deficits, third space losses, and blood loss. An alternative approach would be to use lactated ringers solution for the deficits, third space and blood loss, and then "piggy back" the maintenance fluids, using a constant infusion pump, so as to avoid hypoglycemia in children at risk for hypoglycemia. This avoids the bolus of glucose while maintaining blood glucose values at slightly above baseline. The take-home message is that it is clearly not beneficial and may in fact be harmful to provide a large bolus of intravenous fluid with glucose, thus causing a rapid increase in circulating blood glucose.
1. Sieber FE, Traystman RJ. Special issues: glucose and the brain. Crit Care Med. 1992;20:104-114.
2. Wass CT, Lanier WL. Glucose modulation of ischemic brain injury: review and clinical recommendations. Mayo Clin Proc. 1996;71:801-812.
3. Steward DJ, DaSilva CA, Flegel T. Elevated blood glucose levels may increase the danger of neurological deficit following profoundly hypothermic cardiac arrest. Anesthesiology. 1988;68:653.
4. Coté CJ. NPO after midnight for children„a reappraisal. Anesthesiology. 1990;72:589-592.
What is the optimum dose of caudal morphine as treatment for postoperative pain in children undergoing open cardiac surgery? Would you recommend it or local anesthetics? —Alberto M. Tellerña, Spain
Dr. Karl Responds:
Some people have better luck than others in threading catheters to a thoracic operative site from the caudal space. In general, it is more likely to thread in younger patients. Local anesthetics (e.g., bupivacaine at 0.45 mg/kg/hr for patients > 6 mo.; 0.25 mg/kg/hr if < 6 mo.) are not likely to be very helpful if the catheter tip is not well-placed. You can check the tip position radiographically or by assessing the spread of a loading dose of local anesthetic. Morphine, because of it relative hydrophilicity, spreads rostrally in the epidural space and thus is more likely to provide analgesia from a poorly localized catheter. I usually start at doses of 0.033 mg/kg every 6 hours, with fentanyl 1 mcg/kg ordered to cover inadequate analgesia. Particularly in the first 24 hours, it is imperative that patients receiving epidural opioids be well monitored.
We treat very frecuently problems in infants with traumatisms due to street accidents. My question is: Is there a new transoperatory fluid replacement in this cases? —Juan Reyes MD
Dr. Coté Responds:
There are several new rapid transfusion devices such as the Level 1 and Hot Line. These devices are very effective in warming blood or fluid rapidly transfused. These devices do require some degree of training and they are expensive to set up so the down side is primarily cost however, without doubt these devices are a marked improvement over what was previously available. It should be noted that the major limitation is the size of the iv catheter inserted. This is particularly a problem with multilumen cvp catheters.
References: Henker et al. J Emerg. Evaluation of four methods of warming intravenous fluids. Nursing 21:385-390, 1995
Patel N, et al: Comparison of fluid warmer performance during simulated clinical conditions. Can J Anaesth 42:636-642, 1995
Beebe Ds, et al: Comparison of the flow rates of central venous catheters designed for rapid transfusion in infants and small children. Paediatr Anaesth 5:35-39, 1995
Presson RG, Jr, et al: Evaluation of a new fluid warmer effective at low to moderate flow rates. Anesthesiology 78:974-980, 1993
I have an 11 year old patient who came for constructive surgery on her right hand. The problem is that she suffers from dystrophic epidermolysis bullosa. I do appreciate any advice. How about starting her on corticosteroids as premedication, and would 'L M' be better than intubation. In case of large bullae postoperative should I give fluid replacement? —Rafik Ramzy FFARCS
Dr. Coté Responds:
These patients unfortunately can be quite complicated from our standpoint. Anything that applies pressure to the skin or mucous membranes can cause damage. A mask anesthetic is possible but the pressure needed to hold the mask can cause problems. Generally a very gentle larnygoscopy with a smaller than usual endotracheal tube is safe because this removes pressure on anything —the key is the very gentle and skilled laryngoscopy. Even with this they can develop bullae in the mouth. The iv fluid therapy should be tailored to need - if there are no bullae formation then routine maintenance is adequate. If the child has extensive disease with a lot of damaged skin then yes an increased hourly maintenance will be required. Regarding the corticosteroids - I would consult with her dermatologist regarding the need. If she is chronically on steroids then she will need additional stress doses.
What is the optimum dose of oral midazolam as premedication for children aged 3 years and above; and would you recommend it as premedication for children undergoing T&As? —Yasser Samhan
Dr. Coté Responds:
A number of studies have examined 0.25, 0.5, 0.75 and even 1.0 mg/kg of oral midazolam. Studies from Toronto suggest that a dose of 0.5 mg/kg results in a sedated child within 10 minutes. Studies from a variety of institutions suggest that a dose of 0.5 mg/kg does not delay recovery. The upper limit for total dose has been 15 - 20 mg, but these higher doses in older children may delay recovery. A multicenter randomized study has recently been completed and the data submitted to FDA. Final dose recommendations will result.
I am a pediatric dentist certified in the use of intravenous conscious sedation. I know that there is controversy about the term, but that is not my issue. I am sedating children from roughly three years of age and up using midazolam, nalbuphine and nitrous oxide titrated to clinical effect. The children are responsive (moan, open their eyes, pull away) to mild to moderate stimuli such as insertion of a local anesthetic needle, placement of a rubber dam clamp or the rubber dam or brief pinch of the trapezius so I am certain that they are conscious and their airway and swallowing reflexes are intact. My RN and I are certified in PALS and ACLS and we are monitoring by clinical observation, pulse oximetry, NIBP, pre-tracheal stethoscope, EKG and capnography. My question is about etCO2 measurments in an open system. Is it reliable? The literature appears to be controversial and equivocal. Can you direct me to literature which specifically has examined and interpreted etCO2 measurments in this kind of system? —Angel Manguel
Dr. Karl Responds:
Congratulations on your conscientious monitoring!
ET CO2 measurements in an open system are an excellent tool as long as you do not take the numbers too seriously. By this I mean that the calibrated machine can only report what it sees. So if you are using a nasal cannula and the child is breathing through their mouth, you may not get a good sample. Similarly, if the sampling site is very close to the site of oxygen delivery, the CO2 may be diluted.
So here is what you can know:
- The arterial CO2 is always higher than what you measure in the exhaled sample.
- Changes in the measured CO2 with no other changes in the system probably reflect changes in the patient's airway and/or respiratory drive.
- Low ETCO2 readings probably reflect poor sampling. This may or may not be reflected in the shape of the curve.
- Disappearance of a previously present ETCO2 waveform should lead to checking the patient for airway patency.
ETCO2 measurements are an excellent monitor in this most difficult setting for sedation.
Here are some recent articles:
Schmitz BD. Shapiro BA. Capnography. [Review] [26 refs] Respiratory Care Clinics of North America. 1(1):107-17, 1995 Sep.
Egleston CV. Ben Aslam H. Lambert MA. Capnography for monitoring non-intubated spontaneously breathing patients in an emergency room setting. Journal of Accident & Emergency Medicine. 14(4):222-4, 1997 Jul.
Hart LS. Berns SD. Houck CS. Boenning DA. The value of end-tidal CO2 monitoring when comparing three methods of conscious sedation for children undergoing painful procedures in the emergency department. Pediatric Emergency Care. 13(3):189-93, 1997 Jun.
Abramo TJ. Wiebe RA. Scott S. Goto CS. McIntire DD. Noninvasive capnometry monitoring for respiratory status during pediatric seizures. Critical Care Medicine. 25(7):1242-6, 1997 Jul.
I read a recent article that advocated the use of dexamethasone in children undergoing T&A's. But, for the most part, I find that opinions of most anesthesiologists and ENT surgeons seem not to support that finding. I have (at least anecdotally) found that the patients seem to do better post-operatively in the sense of less discomfort, less agitation, and easier return to oral intake. What is the current opinion on this matter? —Robert A. Larter CRNA
Dr. Karl Responds:
The literature is mixed on this question. Two papers from a single anesthesiology group showed that 150 mcg/kg of dexamethasone (maximum dose = 8 mg) decreased the overall incidence of vomiting from 72% (placebo) to 40% (Anesth Analg 83:913-6, 1996), but was less effective than perphenazine (33%)(Anesth Analg 85:534-7,1997).
Papers from surgical groups generally used a broader range of outcome measures. Several groups used 0.5 mg/kg and showed no differences from placebo. One paper reported significant improvement in pain, vomiting and oral intake in dexamethasone-treated patients than in controls (Int J Pedi Otorhinolaryngol 37:115-20, 1996).
The most compelling paper reported on a comparison of 80 children who received 1 mg/kg IV dexamethasone or placebo before electrocautery dissection tonsillectomy and adenoidectomy. They found significantly less trismus, vomiting and fever in the first 6 hours after surgery in the dexamethasone group (Arch Otolaryngol Head Neck Surg 122:117-20, 1996). No investigator in any of these studies reported adverse effects from a single dose of dexamethasone.
Differences in dosing, surgical technique, timing and adjunct medications make it difficult to compare these papers directly. It appears that single intravenous doses (at least 1 mg/kg) before the beginning of electrocautery dissection tonsillectomy and adenoidectomy are reasonably safe and effective in improving postoperative comfort.
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