Pentobarbital sedation for patients in the pediatric intensive care unit

Sedation, Analgesia, and Paralysis in COVID-19 Patients in the Setting of Drug Shortages

The rapid spread of the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has led to a global pandemic. The 2019 coronavirus disease (COVID-19) presents with a spectrum of symptoms ranging from mild to critical illness requiring intensive care unit (ICU) admission. Acute respiratory distress syndrome is a major complication in patients with severe COVID-19 disease. Currently, there are no recognized pharmacological therapies for COVID-19. However, a large number of COVID-19 patients require respiratory support, with a high percentage requiring invasive ventilation. The rapid spread of the infection has led to a surge in the rate of hospitalizations and ICU admissions, which created a challenge to public health, research, and medical communities. The high demand for several therapies, including sedatives, analgesics, and paralytics, that are often utilized in the care of COVID-19 patients requiring mechanical ventilation, has created pressure on the supply chain resulting in shortages in these critical medications. This has led clinicians to develop conservation strategies and explore alternative therapies for sedation, analgesia, and paralysis in COVID-19 patients. Several of these alternative approaches have demonstrated acceptable levels of sedation, analgesia, and paralysis in different settings but they are not commonly used in the ICU. Additionally, they have unique pharmaceutical properties, limitations, and adverse effects. This narrative review summarizes the literature on alternative drug therapies for the management of sedation, analgesia, and paralysis in COVID-19 patients. Also, this document serves as a resource for clinicians in current and future respiratory illness pandemics in the setting of drug shortages.

A survey for pain and sedation medications in pediatric patients during extracorporeal membrane oxygenation

Routine administration of large amounts of pain and sedative medication is common to critically ill pediatric patients undergoing extracorporeal membrane oxygenation (ECMO) for cardiopulmonary failure. It has been our experience that pediatric patients are the most difficult age group in which to achieve an ideal pain and sedative control due to the narrow margin of safety. The purpose of this study was to determine the general practice guideline used for pain and anxiolytic pharmacotherapy for pediatric patients at ECMO centers. We sent a survey questionnaire to all ECMO centers in the USA that treat pediatric respiratory failure patients. Of the 46 responding centers (including telephone follow-ups), 37 (80%) centers had an active pediatric ECMO programs for patients with severe respiratory failure. Fentanyl was the most commonly used pain medication and continuous infusion, administered directly to the patient, was preferred. Subjective effectiveness of various pharmacological agents was variable without clear consensus; however, midazolam was considered to be the most effective agent used.

Extracorporeal Life Support in Pediatric and Neonatal Critical Care: A Review

Extracorporeal life support (ECLS) is a modified form of cardiopulmonary bypass used to provide prolonged tissue oxygen delivery in patients with respiratory and/or cardiac failure. The first large-scale success of ECLS was achieved in the management of term newborns with respiratory failure. ECLS has become an accepted therapeutic modality for neonates, children, and adults who have failed conventional therapy and in whom cardiac and/or respiratory insufficiency is potentially reversible. The use of ECLS allows one to reduce other cardiopulmonary supports and apply a gentle ventilation strategy in a population of severely compromised critical care patients. ECLS has now been employed in more than 26,000 neonatal and pediatric patients with an overall survival rate of 68%. ECLS has evolved significantly over 25 years of clinical practice; patient selection for this complex and highly invasive therapy, as well as how ECLS is employed in different patient groups, is constantly changing. Generally, ECLS is used more liberally now than in the past. The number of patients requiring this support, however, is declining yearly, and those patients who receive ECLS compose a more severe subset of an intensive care population. This review provides an overview of the development of ECLS and the equipment and techniques employed. The use of ECLS for neonatal respiratory failure, pediatric respiratory failure, and cardiac support are outlined. Management of the ECLS patient is discussed in detail, and outcome of these patients is reviewed. Finally, current trends and future implications of ECLS in neonatal and pediatric critical care are addressed.

Pentobarbital for Sedation during Mechanical Ventilation in the Pediatric ICU Patient

In most pediatric intensive care units (PICUs), sedation is provided using opioids and benzodiazepines, either alone or in combination. While these agents are effective in most patients, certain situations may arise in which this usual combination is ineffective. There are no large series outlining the use of pentobarbital for sedation in the PICU population. The current report is a retrospective review of the use of pentobarbital for sedation of 50 patients in the PICU and provides information concerning the use of phenobarbital to prevent withdrawal symptoms following the prolonged administration of pentobarbital. The 50 patients ranged in age from 1 month to 14 years and in weight from 3.1 to 56 kg. All required sedation during mechanical ventilation. Prior to changing to pentobarbital, sedation was inadequate despite midazolam doses of ≥0.4 mg/kg/hr, fentanyl doses of ≥10 μg/kg/hr, and morphine doses of ≥100 μg/kg/hr. The duration of pentobarbital infusion ranged from 2 to 37 days (median 4 days) in doses ranging from 1 to 6 mg/kg/hr (median 2 mg/kg/hr). Twelve patients also received an ongoing opioid infusion for more than 48 hours after starting the pentobarbital infusion to control pain related to a surgical procedure or an acute medical illness. There was an increase in pentobarbital infusion requirements over time. In the 14 patients that received pentobarbital for 5 days or more, the requirements increased from 1.2 ± 0.4 mg/kg/hr on day 1 to 3.4 ± 0.7 mg/kg/hr on day 5 ( p < 0.01). Pentobarbital was effective in all 50 patients without significant adverse effects.

Sedation in Critically Ill Children with Respiratory Failure

This article discusses the rationale of sedation in respiratory failure, sedation goals, how to assess the need for sedation as well as effectiveness of interventions in critically ill children, with validated observational sedation scales. The drugs and non-pharmacological approaches used for optimal sedation in ventilated children are reviewed, and specifically the rationale for drug selection, including short- and long-term efficacy and safety aspects of the selected drugs. The specific pharmacokinetic and pharmacodynamic aspects of sedative drugs in the critically ill child and consequences for dosing are presented. Furthermore, we discuss different sedation strategies and their adverse events, such as iatrogenic withdrawal syndrome and delirium. These principles can guide clinicians in the choice of sedative drugs in pediatric respiratory failure.

Is anesthesia bad for the newborn brain?

Although certain data suggest that common general anesthetics may be neurotoxic to immature animals, there are also data suggesting that these same anesthetics may be neuroprotective against hypoxicischemic injury, and that inadequate analgesia during painful procedures may lead to increased neuronal cell death in animals and long-term behavioral changes in humans. The challenge for the pediatric anesthesia community is to design and implement studies in human infants to ascertain the safety of general anesthesia. In this article, the authors review the relevant preclinical and clinical data that are currently available on this topic.

Efficacy of sedation regimens to facilitate mechanical ventilation in the pediatric intensive care unit: a systematic review

OBJECTIVE

Children admitted to pediatric intensive care units (PICUs) often receive sedatives to facilitate mechanical ventilation. However, despite their widespread use, data supporting appropriate dosing, safety, and optimal regimens for sedation during mechanical ventilation are lacking. Therefore, we conducted a systematic review of published data regarding efficacy of sedation to facilitate mechanical ventilation in PICU patients. Our primary objective was to identify and evaluate the quality of evidence supporting sedatives used in PICUs for this purpose.

DATA SOURCES

We searched MEDLINE, EMBASE, and The Cochrane Registry of Clinical Trials from 1966 to June 2008 to identify published articles evaluating sedation regimens to facilitate mechanical ventilation in PICU patients.

STUDY SELECTION

We included only those studies of intubated PICU or pediatric cardiac intensive care unit patients receiving pharmacologic agents to facilitate mechanical ventilation that reported quality of sedation as an outcome.

DATA EXTRACTION

We analyzed studies separately for study type and by agents being studied. Studies were appraised using criteria of particular importance for reviews evaluating sedatives.

DATA SYNTHESIS

Our search strategy yielded 39 studies, including 3 randomized trials, 15 cohort studies, and 21 cases series or reports. The 39 studies evaluated a total of 39 different sedation regimens, with 21 different scoring systems, in a total of 901 PICU/cardiac intensive care unit patients ranging in age from 3 days to 19 years old. Most of the studies were small (<30 patients), and only four studies compared one or more agents to another. Few studies thoroughly evaluated drug safety, and only one study met all quality criteria.

CONCLUSIONS

Despite the widespread use of sedatives to facilitate mechanical ventilation in the PICU, we found that high-quality evidence to guide clinical practice is still limited. Pediatric randomized, controlled trials with reproducible methods and assessment of drug safety are needed.

Continuous pentobarbital infusion in children is associated with high rates of complications

PURPOSE

To evaluate the incidence and severity of complications related to continuous pentobarbital (PB) infusion for sedation in the Pediatric Intensive Care Unit (PICU).

MATERIALS AND METHODS

We conducted a retrospective, chart review study. All patients admitted to the PICU from January 1997 through June 1998 who received continuous IV PB infusion for sedation (n = 8) were included.

RESULTS

All patients were intubated and mechanically ventilated prior to PB infusion. PB was used only as a second line sedative after a combination of an opioid and benzodiazepine failed to achieve adequate sedation. After initiation of PB, we were able to decrease or discontinue benzodiazepines and/or opioid doses and discontinue neuromuscular blocking drugs in all patients. We observed a high incidence of complications (62.5%) related to PB or the phenobarbital treatment used for barbiturate weaning, including blood pressure instability (25%), oversedation (12.5%), drug reaction (12.5%) and neurologic sequelae (12.5%). Discontinuation of the drug was required in 25% of the cases.

CONCLUSIONS

We found continuous PB infusion to be an effective sedative for children when other drugs fail. However, we observed a high rate of clinically significant complications requiring discontinuation of the drug.

Managing sedation withdrawal in children who undergo prolonged PICU admission after discharge to the ward

Children who undergo a prolonged stay within the intensive care unit require adequate sedation and analgesia. During the recovery phase there will need to be a period of sedation withdrawal to prevent occurrence of an abstinence syndrome. We present a strategy developed within our hospital for managing this process which uses the resource of the Pain Service, along with guidelines to help prevent the development of withdrawal, and a plan for managing any signs of abstinence which occur.

Plasma concentrations of midazolam in neonates receiving extracorporeal membrane oxygenation

Drug disposition is affected during extracorporeal membrane oxygenation (ECMO). This study investigates the dose-concentration relationship of midazolam in neonates requiring ECMO during continuous infusion into the circuit (extracorporeally; n = 10) and intravenously (n = 10). Data on hourly doses and sedation scores were collected for 120 hours. Plasma concentrations were analyzed at times 0, 2, 4, 6, 12, 18, and 24, and every 12 hours thereafter. Both groups were clinically similar. Mean (standard deviation) dose for all patients was 250 (185) microg/kg/h, four times greater than previously reported. Doses administered in the first 24 hours were significantly greater extracorporeally [361 (300)] compared with intravenous [258 (190) microg/kg/h, p < 0.001]. Mean (standard deviation) plasma concentrations in all patients at 24, 48, and 72 hours were 1.4 (0.9), 1.8 (1.2), and 2.6 (1.8) microg/ml, respectively. Satisfactory sedation levels were achieved in all patients. Comparison of the actual observed with predicted (simulated) midazolam concentrations suggested significant attenuation of plasma levels during the first 24 hours of ECMO. However, at 48 hours, observed concentrations exceeded those predicted, suggesting accumulation. We conclude that in the first 24 hours of ECMO, because of an expanded circulating volume and sequestration by the circuit, significantly more midazolam is required to achieve adequate sedation. Subsequently, and because of circuit saturation, maintenance doses should be reduced.

Tolerance, withdrawal, and physical dependency after long-term sedation and analgesia of children in the pediatric intensive care unit

OBJECTIVE

To describe the consequences of the prolonged administration of sedative and analgesic agents to the pediatric intensive care unit (PICU) patient. The problems to be investigated include tolerance, physical dependency, and withdrawal.

DATA SOURCES

A MEDLINE search was performed of literature published in the English language. Cross-reference searches were performed using the following terms: sedation, analgesia with PICU, children, physical dependency, withdrawal; tolerance with sedative, analgesics, benzodiazepines, opioids, inhalational anesthetic agents, nitrous oxide, ketamine, barbiturates, propofol, pentobarbital, phenobarbital.

STUDY SELECTION

Studies dealing with the problems of tolerance, physical dependency, and withdrawal in children in the PICU population were selected.

DATA EXTRACTION

All of the above-mentioned studies were reviewed in the current manuscript.

DATA SYNTHESIS

A case by case review is presented, outlining the reported problems of tolerance, physical dependency, and withdrawal after the use of sedative/analgesic agents in the PICU population. This is followed up by a review of the literature discussing current treatment options for these problems.

CONCLUSIONS

Tolerance, physical dependency, and withdrawal can occur after the prolonged administration of any agent used for sedation and analgesia in the PICU population. Important components in the care of such patients include careful observation to identify the occurrence of withdrawal signs and symptoms. Treatment options after prolonged administration of sedative/analgesic agents include slowly tapering the intravenous administration of these agents or, depending on the drug, switching to subcutaneous or oral administration.

Issues of pharmacology in pediatric cardiac extracorporeal membrane oxygenation with special reference to analgesia and sedation

Sufficient analgesia, sedation, and paralysis, if necessary, are cornerstones of extracorporeal membrane oxygenation (ECMO) treatment protocols. However, increased distribution volumes, drug absorption by circuit materials, and impaired drug elimination, as well as alternations of cerebral perfusion and blood brain barrier function, result in the markedly altered pharmacodynamics of applied drugs. Today, narcotics combined with benzodiazepines, sometimes enforced by barbiturates, are commonly used in clinical practice. Paralysis is usually achieved by pancuronium or vecuronium. Although these drugs are used widely, actual efficacy remains uncertain because of the lack of reliable tools to measure pain relief and degree of sedation during ECMO, especially during paralysis. Taking into account the detrimental effects of insufficient pain relief and inadequate sedation in such unstable patients as children during pediatric cardiac ECMO, further studies on this topic seem urgently necessary.

Sedation and analgesia in paediatric intensive care units: a guide to drug selection and use

The indications for sedation in the paediatric intensive care unit (PICU) patient are varied ranging from short term use for various procedures to prolonged administration to provide comfort during mechanical ventilation. When faced with the decision to institute sedation, the healthcare provider must make three decisions: the agent to be used, the route of delivery, and the mode of administration (intermittent versus continuous). There are several agents that have been used to provide sedation in the PICU patient including the inhalational anaesthetic agents, benzodiazepines, opioids, ketamine, propofol, chloral hydrate, phenothiazines, and the barbiturates. This review describes the various agents for sedation and discusses their advantages and disadvantages as they pertain to the PICU. Consequences of and treatment strategies for long term problems with prolonged sedation including tolerance, physical dependency, and withdrawal are reviewed.

Complications of sedation with midazolam in the intensive care unit and a comparison with other sedative regimens

OBJECTIVE

To describe the various complications that have been reported with use of midazolam for sedation in the intensive care unit (ICU).

DATA SOURCES

Publications in scientific literature.

DATA EXTRACTION

Computer search of the literature.

SYNTHESIS

Sedation is required in the ICU in order for patients to tolerate noxious stimuli, particularly mechanical ventilation. Under- and oversedation can lead to complications. To sedate patients in the ICU, midazolam is commonly administered via titrated, continuous infusions. Cardiorespiratory effects tend to be minimal; however, hypotension can occur in hypovolemic patients. Prolonged sedation after cessation of the midazolam infusion may be caused by altered kinetics of the drug in critically ill patients or by accumulation of active metabolites. In addition, paradoxical and psychotic reactions have been rarely reported. Tolerance and tachyphylaxis may occur, particularly with longer-term infusions (> or = 3 days). Benzodiazepine withdrawal syndrome has also been associated with high dose/long-term midazolam infusions. Compared with propofol infusions, midazolam infusions have been associated with a decreased occurrence of hypotension but a more variable time course for recovery of function after the cessation of the infusion. Lorazepam is a more cost-effective choice for long-term (> 24 hrs) sedation.

CONCLUSION

Continuous infusion midazolam provides effective sedation in the ICU with few complications overall, especially when the dose is titrated.

Sedation with intravenous midazolam in the pediatric intensive care unit

Physical and emotional distress can have important effects on patients in the pediatric intensive care unit (ICU). Intravenous (IV) infusion of benzodiazepines is an important adjunct to assisted ventilation and other potentially distressing ICU procedures. Combined with intermittent or continuous infusion of opioids, the benzodiazepines provide smooth control of anxiety, pain, and agitation. Intravenous midazolam (Versed Roche Laboratories) is distinguished from diazepam (Valium, Roche Products) by its water solubility, short elimination half-life, and generally short duration of action. These pharmacological properties, which are also shared, in part, with the more slowly eliminated drug lorazepam (Ativan, Wyeth-Ayerst), facilitate titration of the rate of infusion against patient response and permit regulation of the depth of sedation. The major adverse effects of long-term benzodiazepine infusion are withdrawal symptoms and, occasionally, delayed awakening. The dosage needed to initiate and maintain sedation must be adjusted to body weight, degree of sedation desired, and concomitant medications, as well as to underlying health and cardiovascular status. Benzodiazepines, such as midazolam and lorazepam, represent important choices among drugs used for sedation in the pediatric ICU.

Nicardipine to control mean arterial pressure during extracorporeal membrane oxygenation

The authors present the use of nicardipine to control mean arterial pressure (MAP) in a 19-month-old boy who required venoarterial extracorporeal membrane oxygenation for 11 days for treatment of hydrocarbon aspiration. Nicardipine is an intravenously administered dihydropyridine calcium channel antagonist whose primary physiological action includes vasodilatation. Unlike other calcium channel blockers, it has limited effects on the inotropic and dromotropic function of the myocardium. Nicardipine was started at 5 micrograms.kg-1.min-1 and within five min lowered the MAP from a maximum value of 108 mmHg back to the baseline range of 60 to 80 mmHg. Once the MAP had returned to baseline values, infusion requirements varied from 1 to 3 micrograms.kg-1.min-1 to maintain the MAP at 60 to 80 mmHg during the 11 days of ECMO. No increase in dose requirements were noted during the 11 days.

Sedation and Analgesia for Children in the Pediatric Intensive Care Unit

Several situations arise in the Pediatric Intensive Care Unit (PICU) patient which may require the pharmacologic control of pain and anxiety. The author discusses the various pharmacologic agents available for sedation and analgesia including the inhalational anesthetic agents, nitrous oxide, benzodiasepines, opioids, ketamine, propofol, and the barbiturates. While intravenous administration is generally chosen for the PICU patient, certain situations may arise which preclude this route. The available information concerning alternative routes of delivery for the various agents including subcutaneous and transmucosal administration is presented. The role of various regional anesthetic techniques to control pain in the PICU patient are reviewed.

Outpatient therapy of iatrogenic drug dependency following prolonged sedation in the pediatric intensive care unit

The authors present their clinical experience with the oral administration of lorazepam, methadone, and pentobarbital to prevent or treat withdrawal symptoms following prolonged sedation in the PICU patient. The 3 patients presented required prolonged sedation for mechanical ventilation. Different agents were used for sedation in the 3 patients including intravenous fentanyl, midazolam, and pentobarbital. The switch to oral agents must take into consideration the differences in potency, half-life, and oral bioavailability between the agents. The authors discuss the appropriate conversion factors for opioids, benzodiazepines, and barbiturates. The switch to oral administration eliminated the need for intravenous access in the 3 patients and allowed for earlier discharge home. All 3 patients were discharged home on an oral, taper schedule. Such an approach may lead to earlier home discharge thereby improving the patient's quality of life as well as saving health care dollars.