ASA meeting reviews
TIVA for TOTS
By Zulfiqar Ahmed, MD
Director of Pediatric Anesthesia and CME
Anesthesia Associates of Ann Arbor
Drs. Zulfiqar Ahmed (Standing), Greg Schears, Mark Ansermino and Sam Sharar
Sam R. Sharar, MD (University of Washington, Seattle) was the session’s first speaker. He discussed methods to decrease patient anxiety, as well as cognitive distraction techniques when starting an intravenous line (IV) in a child. A child’s perception of psychological and physical discomfort in the hospital depends on a number of factors. Confirmed contributors of anxiety for IV placement are age, co-existing diagnosis, coping style, previous experience, impulsivity, parental coaching and preparation. Among these factors, only patient preparation and parental coaching are modifiable. When preparing a child for IV placement, important factors are:
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Share procedure details honestly and in advance
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Include the child and parents in planning
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Use demonstrations, graphics and videos to increase success.
When preparing the parent for their child’s IV placement, important factors are:
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Equip parents (if willing) with distraction coaching
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Use child’s favorite toys, books and devices as available
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Presence of a child life specialist is ideal
One may consider placing the distractor (books, videos) between the child’s view and IV site. When these resources are not present or are limited, then premedication can be an important part of pre operative preparation.
Gregory J. Schears, MD (Mayo Clinic) presented various technologies useful for facilitating IV access. Difficult vascular access (DVA) is easier to describe than define and includes peripheral, central and or arterial line placement. It depends upon patient condition, clinician skill, luck and equipment availability. DVA in pediatric patients is most common in very young, obese, dark skin toned, edematous or uncooperative patients. Use of ultrasound and near infra-red technology to highlight/augment visualization of veins was discussed. These techniques allow anesthesiologists to see what eyes and fingers cannot find. They can help improve efficiency as DVA is a fairly common phenomenon. These methods can also increase patient and professional satisfaction.
In order to develop ultrasound skills, one needs patience and practice. It takes time to achieve proficiency, understand the sono-anatomy and master necessary manual dexterity skills. To gain confidence and skill, one should use ultrasound for every day IV starts, starting with older children or adults. Optimal technique includes immobilizing and supporting the extremity, sitting in a comfortable position and having the screen face the operator in a neutral position. Lights may be dimmed to improve screen view.
Additional tips include using plenty of sterile gel and avoiding air bubbles within the gel. Excessive amount of gel may affect clean up once the IV is in and needs to be secured. With an in-plane approach, a tortuous vessel may pose problems and a steady hand is essential for success. With an out-of-plane approach, the needle tip may be poorly visualized and alignment of needle and vessel may be problematic.
Near Infrared technology (NIR) includes two types, reflective and transmitive, and offers many advantages. NIR for patient care is especially useful in edematous or obese patients, when more venous access options are needed. This modality helps in choosing the most optimal site, particularly when vessel bifurcations, cul-de-sacs, valves and previous catheter sites make IV placement difficult.
Mark J. Ansermino, MBBCh, FRCPC (British Columbia Children’s Hospital, Canada) concluded the panel discussion with an exploration titled “TIVA in Kids - What Works?” Propofol and Remifentanil are the two most important drugs in TIVA but are not approved for this purpose in children less than three years of age. According to the manufacturers, this is due to insufficient experience and/or safety data. With reference to Propofol, the main concern is Propofol Infusion Syndrome (PIS).
The aetiology for PIS includes impaired fatty acid metabolism (failure of tissue oxygenation), failure of mitochondrial metabolism, suppression of fat metabolism (acyl-carnitine) and exacerbation of inherited defects in beta oxidation.
Published advantages of TIVA in children include:
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Anesthetic of choice for airway procedures (obtunds airway reflexes and causes bronchodilatation)
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Improved respiratory ciliary function
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Easy titratability
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Ability to maintain spontaneous ventilation
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Non-reliance on airway for anesthesia
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No volatile inhalation by surgeon
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Good, quick quality of recovery
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Reduced emergence delirium
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No environmental pollution
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neuro-protection
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Reduced PONV
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Reduced cost
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Myocardial protection,
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Antiepileptogenic
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Reduced risk for awareness
Dr. Ansermino concluded by offering anesthetic dosing guidelines for airway surgery as follows:
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Dexmedetomidine 0.5-1 µg/kg bolus
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Propofol infusion titrated to keep EEG index < 45 (40 at start)
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Remifentanil infusion to keep RR < 15
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Good topical analgesia