Lower-Dose Propofol Use for MRI: A Retrospective Review of a Pediatric Sedation Team's Experience.

OBJECTIVE: The aim of the study was to evaluate, in children undergoing procedural sedation for magnetic resonance imaging (MRI) scans, whether lower doses of propofol than previously published permitted a high rate of successful MRI completion, whether lower dosages result in a more rapid recovery, and whether age or behavioral diagnosis increases propofol requirements. METHODS: After institutional review board approval, we retrospectively reviewed the pediatric sedation team's sedation database of children receiving propofol infusion for MRI scans between 2007 and 2016. Data collected included propofol induction dose (in milligrams per kilogram), propofol infusion dose (in micrograms per kilogram per hour), total propofol dose (in milligrams per kilogram and in milligrams per kilogram per hour), and the number of administered ancillary sedative medications. Additional data included the American Society of Anesthesiologist status, sedation duration, recovery duration, and successful completion of MRI. Dosing data were also stratified by age. RESULTS: A total of 2354 patients met inclusion criteria. Eight percent of patients received propofol infusion alone, 79% received midazolam before their propofol induction, and 13% received a combination of propofol and other drugs. Mean induction dose was 2.2 + 0.9 mg/kg, mean infusion dose was 93.5 + 29.0 µg/kg per minute, and total mean dose was 9.0 + 3.0 mg/kg per hour. Mean recovery time was 44 minutes, and 99.3% of the scans were completed with good images. We noted an increase requirement in the mean induction dose and total dose in children younger than 1 year. CONCLUSIONS: Propofol infusion doses lower than commonly reported permit successful completion of scans and similar recovery times in a single institution. Younger children require more propofol for successful procedural sedation.

High-Dose Sedation and Analgesia During Extracorporeal Membrane Oxygenation: A Focus on the Adjunctive Use of Ketamine.

Use of ketamine in patients requiring extracorporeal membrane oxygenation (ECMO) has rarely been reported, and the optimal dosing strategy remains unclear. A patient admitted with hypoxic respiratory failure required ECMO in addition to continuous infusion of low-dose ketamine following titration of opioid and sedative medications to high doses. After initiation of ketamine, infusion rates of opioids and/or sedatives were maintained or decreased. Recorded Richmond Agitation-Sedation Scale (RASS) scores were -4 to -5 and documented pain scores were 0. No adverse effects were reported while receiving low-dose ketamine. This case illustrates that use of low-dose ketamine infusion may be a useful adjunctive agent in patients receiving ECMO and high-dose opioid and sedative medications.

Chloramphenicol toxicity revisited: a 12-year-old patient with a brain abscess.

Chloramphenicol, a broad-spectrum antibiotic, is rarely used in the United States due to its well-described adverse effects. Because of its limited use, many clinicians are unfamiliar with its indications, spectrum of activity, and potential adverse drug effects. We describe a 12-year-old patient who presented after two craniotomies for a persistent brain abscess complicated by long-term chloramphenicol administration. Findings for this patient were consistent with many of the adverse drug effects associated with chloramphenicol, including elevated chloramphenicol serum concentrations, anemia, thrombocytopenia, reticulocytopenia, and severe metabolic acidosis. Rare manifestations of chloramphenicol toxicity that developed in this patient included neutropenia, visual field changes, and peripheral neuropathy. Chloramphenicol administration was discontinued, and hemodialysis was initiated for severe metabolic acidosis. The patient recovered with severe visual field deficits. Although chloramphenicol is rarely indicated, it remains an effective antibiotic. Healthcare providers should become familiar with the pharmacology, toxicology, and monitoring parameters for appropriate use of this antibiotic.

Improvement in long-term ECMO by detailed monitoring of anticoagulation: a case report.

INTRODUCTION: The use of unfractionated heparin (UFH) as an anticoagulant during long-term extracorporeal support presents a unique challenge for the clinician in balancing the amount of anticoagulant to maintain adequate anticoagulation without causing excessive bleeding. Activated clotting times (ACT) and activated partial thromboplastin times (aPTT) are the most common modality to monitor UFH on extracorporeal membrane oxygenation (ECMO). Limitations to these tests include consumptive coagulopathies, clotting factor deficiencies, platelet dysfunction, and fibrinolysis. The following case report describes the use of alternative monitoring strategies to assess more accurately anticoagulation during ECMO. CASE REPORT: A 20-month-old female presented to the emergency department with a 5-6 day history of cough, fever, tachypnea, and respiratory distress. She was diagnosed with influenza A and B with pneumonia. The patient was placed on veno-venous ECMO (V-V ECMO) after mechanical ventilation failed. On ECMO day eight, the patient developed a thrombus in her inferior vena cava and pleural effusions, obstructing cannula flow. Laboratory tests revealed the ACT was within range, yet the aPTT was dropping, despite increased heparin. Heparin levels were low and antithrombin-III (AT) concentrations were 40%. Recombinant AT was given and subsequent aPTTs were within the therapeutic range. Later, the aPTT decreased to <50 sec, heparin levels were within the therapeutic range, while fibrinogen was >475 mg/ dL, and Factor VIII >150 IU/dL, suggesting an acute phase reaction or ongoing systemic inflammation, increasing the risk for thrombosis. We maintained heparin assays between 0.5-0.7 IU/mL and AT >60% to assure heparin's effect. The patient showed no signs of excess bleeding, blood product administration, or clots in the circuit, suggesting proper anticoagulation. The patient was successfully weaned on day 33 and is currently alive and at home. CONCLUSION: Monitoring of anti-Xa UFH and AT proved effective for measuring anticoagulation and detecting inconsistencies in other anticoagulation parameters, leading to steady levels of heparin without further complications.

Central venous access via external jugular vein in children.

OBJECTIVE: To determine the success rate and complications of using the external jugular (EJ) vein for central venous access in pediatric patients. METHODS: Prospective cohort study of children who underwent attempts at EJ vein central venous access while receiving care in an 11-bed pediatric intensive care unit at an urban children's hospital. RESULTS: Over a period of 15 months, 50 patients had EJ venous cannulation attempts. Central venous access was achieved in 45 patients (90%). Successful central venous access was performed in 4 children (50%) younger than 1 year and in 36 older children (98%). Catheter-tip malposition on chest radiograph required subsequent line manipulation in 2 patients. No complications of pneumothorax or carotid artery puncture occurred during line insertion. The catheters were used for an average of 7.5 days (range, 1-28 days). Catheter malfunction occurred in 4 (1.21/100 catheter-days), and catheter-related bloodstream infections occurred in 2 patients (6.04/1000 catheter-days). No thrombotic complications were clinically detected. CONCLUSIONS: The EJ vein is a viable site for central venous access with a low complication rate in pediatric patients.

Acute liver failure in children.

OBJECTIVE: To review the incidence, etiologies, pathophysiology, and treatment of acute liver failure (ALF) in children. Emphasis will be placed on the initial management of the multiple organ system involvement of ALF. METHOD: MEDLINE search from 1970 to March 2005 was performed. Search headings were as follows: acute liver failure, fulminant liver failure, pediatric liver failure, hepatic encephalopathy, and liver transplantation. Studies written in English were selected. Pediatric studies were emphasized. Adult studies were referenced if there were no pediatric studies available in regard to a specific aspect of liver failure. CONCLUSIONS: Pediatric acute liver failure is a rare but life-threatening disease. The common etiologies differ for given age groups. Management includes treating specific causes and supporting multiple organ system failure. Commonly associated disorders that require initial recognition and treatment include energy production deficiencies (hypoglycemia), coagulation abnormalities, immune system dysfunctions, encephalopathy, and cerebral edema. Criteria used to determine the need for liver transplant are reviewed as well as the difficulties associated with predicting which patients will meet these criteria and how rapidly liver transplant will become the only option. Finally, experimental procedures that may provide additional time for the liver to recover are briefly reported.

Pediatric hyperglycemic hyperosmolar syndrome: diagnostic difficulties and high mortality rate.

Childhood obesity has become a pandemic health care problem. A complication of childhood obesity is type 2 diabetes mellitus which has increased 10-fold in the past 20 years. A serious complication of type 2 diabetes mellitus is hyperglycemic hyperosmolar syndrome (HHS). The following case is an obese adolescent boy with a newly diagnosed HHS. The demographic and clinical characteristics of our case and those of 17 other cases from recently published small case series are presented. Of the 18 cases, there were 13 deaths (72%). The purpose of this report and literature review is to emphasize the importance of early diagnoses and treatment of pediatric HHS.

Pediatric extracorporeal membrane oxygenation (ECMO): a review of the first ten years of experience at the Medical University of South Carolina.

ECMO can be life saving in pulmonary emergencies unresponsive to conventional ICU support. ECMO technology and expertise has increased immensely over the last decade. Our experience, and others, has demonstrated that the earlier the referral to an ECMO center, the better chance of survival these patients will have. Our survival results exceed the national average and we have used this therapy in a wide variety of disease processes. Long-term sequelae in survivors are infrequent, as most patients return to normal pulmonary function.

Critical care challenges in the adult ECMO patient.

Extracorporeal membrane oxygenation (ECMO) represents an alternative method of pulmonary support for the critically ill patient with severe respiratory distress. It is commonly used in the neonatal and pediatric populations and is being used with increasing frequency in adults. Although ECMO is not new to the intensive care unit setting, it is usually considered a last resort measure in the adult population. ECMO may save a life and present an awarding challenge to the intensive care unit nurse.

Use of extracorporeal membrane oxygenation in a patient with diffuse alveolar hemorrhage.

Extracorporeal membrane oxygenation (ECMO) was developed as a supportive therapy for severe respiratory failure. It has been shown to be life-saving in neonates and children with isolated respiratory failure, however, its usefulness in adults remains controversial. We report the successful use of ECMO in an adult patient with severe hypoxemic respiratory failure secondary to diffuse alveolar hemorrhage from Wegener granulomatosis.

Pneumococcus-induced T-antigen activation in hemolytic uremic syndrome and anemia.

The hemolytic uremic syndrome (HUS) is most commonly associated with Escherichia coli, but has been associated with other infections such as Streptococcus pneumoniae. Pneumococcus-induced HUS carries an increased risk of mortality and renal morbidity compared with E. coli-induced HUS. The pneumococcal organism produces an enzyme, which can expose an antigen (T-antigen) present on erythrocytes, platelets, and glomeruli. Antibodies to the T-antigen, normally found in human serum, bind the exposed T-antigen, and the resultant antigen-antibody reaction (T-activation) can lead to HUS and anemia. Clinicians need to be aware to request specific testing when pneumococcus-induced HUS/anemia is suspected, as current blood banking techniques do not routinely test for the presence of the T-antigen. Once this association is documented, washing all blood products and avoiding plasma products, if possible, is recommended. Plasmapheresis can be considered for the more critically ill patient. The incidence of pneumococcus-induced HUS may be increasing. We report six cases of pneumococcus-induced HUS/anemia presenting at our hospital.

Intrapleural instillation of fibrinolytic agents for treatment of pleural empyema.

OBJECTIVE: To describe the use of intrapleural instillation of fibrinolytic agents as adjunctive therapy for children with complicated pleural effusions and empyema. DESIGN: Retrospective chart review. SETTING: Tertiary care children's hospital in an academic medical center. PATIENTS: Nineteen consecutive patients (median age, 36 months; range, 9 months to 13 yrs) with complicated pleural effusion or empyema by clinical, radiographic, and laboratory criteria who failed to have adequate drainage of the fluid collection by tube thoracostomy. INTERVENTIONS: Patients who remained symptomatic with fever or respiratory distress and who had pleural fluid that could not be drained by tube thoracostomy were treated by intrapleural instillation of either urokinase (13 patients) or streptokinase (six patients) 8-72 hrs after chest tube insertion. MEASUREMENTS AND MAIN RESULTS: Fibrinolytic therapy increased the volume of chest tube drainage in 15 (79%) of 19 patients. Fourteen of the 19 patients were successfully managed without referral for surgical drainage. No significant adverse events or side effects were noted. CONCLUSION: Intrapleural instillation of fibrinolytic agents appears to be an effective and less invasive alternative to surgical drainage for children who have complicated pleural effusions or empyemas that do not drain adequately with tube thoracostomy alone.