e211CHAPTER 136 Board Review Questions Rationale The use of inhalational agents in the PICU involves the use of equipment that may be unfamiliar to pediatric intensive care physicians Isoflurane appea[.]
CHAPTER 136 Board Review Questions Rationale The use of inhalational agents in the PICU involves the use of equipment that may be unfamiliar to pediatric intensive care physicians Isoflurane appears to be the best choice, and it offers several useful advantages, including the ability to deeply sedate patients (especially those who are difficult to sedate) without polypharmacy Although they are poorly defined at present, tolerance and a withdrawal-like syndrome have been described; however, they appear to occur more slowly than with other sedative agents Multiple case reports of the use of inhalational agents for status asthmaticus in both adults and children have been published Because of its speed of onset and its bronchodilation effects, isoflurane is a useful adjunct to a2-adrenergic agonists If no improvement occurs, or if unacceptable adverse effects occur, then its effects rapidly wane on discontinuation Isoflurane is recommended for use because of its safer adverse effect profile No reports have been made of renal or hepatic dysfunction despite use of isoflurane for prolonged periods Hypotension seems to be more common in patients receiving isoflurane; it is possibly related to increased intrathoracic pressure and the potential for greater preload reduction with vasodilation Fluid boluses are often required, and occasionally vasopressors are required as well Because isoflurane is not an analgesic agent, opiates may need to be administered for painful or uncomfortable procedures In addition, when the patient is weaned off the isoflurane, additional sedatives will be required Chapter 133: Tolerance, Dependency, and Withdrawal Which agent has the highest oral bioavailability? A Dexmedetomidine B Hydromorphone C Methadone D Midazolam E Morphine Preferred response: C Rationale Advantages of methadone include its longer half-life, allowing for dosing 2–3 times per day, an oral bioavailability of 75–90%, and availability as a liquid Signs and symptoms of withdrawal may include all of the following except: A Agitation B Bradycardia C Dilated pupils D Feeding intolerance E Hypertension Preferred response: B Rationale In general, signs and symptoms of withdrawal involve three major end-organ systems, including the autonomic nervous system, the gastrointestinal tract, and the cardiovascular system Activation and stimulation of the autonomic nervous system results in tachycardia and hypertension e211 A genetically predetermined lack of sensitivity to a medication related to a lack of or alteration in receptors or their subcellular components is known as: A Inherent tolerance B Innate tolerance C Learned tolerance D Pharmacodynamic tolerance E Pharmacokinetic tolerance Preferred response: B Rationale Although rarely encountered in the Pediatric ICU population, innate tolerance is lack of sensitivity to a medication related to a lack of or alteration in receptors or their subcellular components related to genetic variation Pharmacokinetic (dispositional) tolerance refers to changes in a medication’s effects because of alterations in distribution or metabolism Learned tolerance refers to a reduction in a drug’s effect as a result of learned or compensatory mechanisms such as learning to walk a straight line while intoxicated by repeated practice at the task Pharmacodynamic tolerance occurs when drug effect is diminished, although the plasma concentration of the drug remains constant The development of physical dependency is most closely linked to: A The age of the patient B The agent used for sedation C The duration of the infusion D The gender of the patient E The maximum infusion rate Preferred response: C Rationale Regardless of the agent used for sedation, the factors that determine the incidence of withdrawal include the total dose administered over the ICU stay and the duration of the infusion While the dose varies based on the agent, for sedative and analgesics, the incidence of withdrawal approximates 50% for days of administration and 100% for days of administration Which of the following is a predominant clinical finding with dexmedetomidine withdrawal? A Bradycardia B Emesis C Hypertension D Miosis Preferred response: C Rationale Dexmedetomidine is a centrally acting a2-adrenergic agonist that decreases central sympathetic outflow Clinical effects include not only sedation but also a slowing of heart rate and a lowering of blood pressure With abrupt discontinuation following its prolonged administration, activation of the sympathetic nervous system occurs with tachycardia and hypertension Similar clinical findings have been reported with the abrupt withdrawal of clonidine e212 S E C T I O N XV Pediatric Critical Care: Board Review Questions Chapter 134: Pediatric Delirium Pediatric literature has demonstrated decreased delirium rates with the following practice: A Benzodiazepine-based sedation B Daily monitoring of electrolytes C Haloperidol prophylaxis D Implementation of routine delirium screening Preferred response: D Rationale Several studies have demonstrated a decrease in delirium rates after implementation of unit-wide delirium screening With early detection of delirium, and careful attention to the triggers, the burden of delirium can be decreased There is no evidence that antipsychotics prevent or cure delirium, either in adults or children Benzodiazepines have been causally implicated in delirium pathogenesis Delirium in children has NOT been associated with the following outcome: A Increased costs B Increased ICU length of stay C Increased duration of invasive mechanical ventilation D Long-term cognitive impairment E Mortality Preferred response: D Rationale Pediatric delirium has been independently associated with increased duration of mechanical ventilation and longer intensive care unit length of stay There is an excess mortality noted with pediatric delirium, and a dramatic increase in hospital costs Delirium in adults has been associated with long-term cognitive impairment Similar studies, investigating the longer-term effects of delirium in PICU survivors, have not yet been conducted in pediatrics Delirium cannot be diagnosed in the presence of: A Coma B Infancy C Sedation D Significant developmental delay Preferred response: A Rationale Delirium can be reliably diagnosed in nearly all children With attention to developmental stage, delirium can be diagnosed in infancy With establishment of alteration from the child’s neurologic baseline, delirium can be diagnosed in children with developmental delay Children who are mechanically ventilated and/or sedated can be assessed for delirium as well, as long as they are arousable to verbal stimulation and not in a coma Which of the following is NOT a risk factor for delirium in children? A Developmental delay B Increased severity of illness C Infancy D Invasive mechanical ventilation Preferred response: C Rationale Children at increased risk for developing delirium when critically ill include those with higher severity of illness, those requiring invasive mechanical ventilation, those with baseline developmental delay, and those between the ages of and years Infants are not at increased risk for developing delirium when compared with children older than years of age Chapter 135: Procedural Sedation for the Pediatric Intensivist A 14-year-old girl admitted to the inpatient nephrology service is undergoing renal biopsy for concern for focal segmental glomerulosclerosis Upon review of her chart, it is noted that her blood pressure measurements have been consistently over 130/80 on repeated occasions She is evaluated by the hospital’s sedation team Her coagulation panel and complete blood count are within normal limits Which of the following agent(s) would be best suited to provide adequate procedural sedation for this procedure? A Dexmedetomidine IV 0.5 µg/kg/h infusion and fentanyl IV µg/kg bolus B Midazolam intranasal 0.4 mg/kg and ketamine IV mg/kg/h infusion C Propofol bolus followed by IV 6–9 mg/kg/h infusion and fentanyl IV µg/kg slow push D Propofol IV 2–3 mg/kg slow push Preferred response: C Rationale Pediatric sedation specialists must have in-depth knowledge of the sedative, reversal, and rescue agents available in their arsenal In the case of a renal biopsy, which is invasive, painful, and requires patient immobility, the sedation specialist must administer agents that provide deep sedation and subsequent analgesia To achieve this therapeutic effect, propofol and fentanyl would be the agents to best be administered Propofol is easily titratable as an infusion to provide immobility and sedation; however, it does not adequately provide analgesia Thus, fentanyl should adjunctively be administered about 5–7 minutes prior to propofol to provide analgesia A dose of mg/kg IV (maximum of 50 mg) is usually sufficient Although intranasal midazolam and ketamine infusion may be appropriate, in a child with glomerulonephritis and likely hypertension, one would want to avoid further exacerbating elevated blood pressures with ketamine A 6-week-old boy presents for a sedated auditory brainstem response (ABR) test You would like to prescribe an agent which is least neurotoxic and in correlation with the U.S Food and Drug Administration (FDA) guidelines for children less than years old undergoing a repeated or lengthy procedure Which of the following agents is best used in this scenario? A Dexmedetomidine B Etomidate C Ketamine D Propofol Preferred response: A CHAPTER 136 Board Review Questions Rationale In 2016, based on strong preclinical studies and some human observations, the US FDA issued a drug safety announcement warning that repeated or lengthy (greater than hours) use of general anesthetic and sedating drugs during surgeries or procedures in children less years of age, or in pregnant women during their third trimester, may affect neuronal development These medications included etomidate, propofol, and ketamine Animal and human studies have shown dexmedetomidine may in fact have neuroprotective properties Pediatric critical care physicians should take every opportunity to avoid deep or generalized sedation with neurotoxic medications in infants and neonates especially for prolonged procedures A teenage boy is recently diagnosed with acute T lymphoblastic leukemia He is scheduled in the sedation unit for a bonemarrow biopsy, aspiration, and lumbar puncture Upon review of his history and exam, which of the following would be the greatest contraindication for procedural sedation? A Apnea-hypopnea index greater than B ASA class III C Diet soda consumption hours prior D Mediastinal mass Preferred response: D e213 Rationale Not all pediatric patients are candidates for sedation Sedation providers should be aware that certain pediatric conditions necessitate the expertise of pediatric anesthesia providers Such examples include difficult airway (determined by history or physical exam), microcephaly, micrognathia, retrognathia, mandibular/ midface hypoplasia or complex genetic syndromes with known complex airway anatomy In addition, patients with ASA physical status classification of or higher, obstructive sleep apnea (as defined by an apnea-hypopnea index (AHI) of greater than 10), morbid obesity, and complex cardiopulmonary disease (such as unrepaired congenital heart disease) are not the best candidates for outpatient procedural sedation Consultation with an anesthesiologist is strongly recommended A child with mediastinal mass should be approached with caution given tenuous changes in cardiopulmonary interactions which may occur during sedation Such cases warrant a multidisciplinary discussion with anesthesia, surgery, ECMO, and primary services Conf idence is ClinicalKey Evidence-based answers, continually updated The latest answers, always at your fingertips A subscription to ClinicalKey draws content from countless procedural videos, peer-reviewed journals, patient education materials, and books authored by the most respected names in medicine Your patients trust you You can trust ClinicalKey Equip yourself with trusted, current content that provides you with the clinical knowledge to improve patient outcomes Get to know ClinicalKey at store.clinicalkey.com 2019v1.0 ... panel and complete blood count are within normal limits Which of the following agent(s) would be best suited to provide adequate procedural sedation for this procedure? A Dexmedetomidine IV 0.5... include difficult airway (determined by history or physical exam), microcephaly, micrognathia, retrognathia, mandibular/ midface hypoplasia or complex genetic syndromes with known complex airway... years old undergoing a repeated or lengthy procedure Which of the following agents is best used in this scenario? A Dexmedetomidine B Etomidate C Ketamine D Propofol Preferred response: A CHAPTER