Paracetamol-induced fulminant hepatic failure in a child after 5 days of therapeutic doses

Sub-Tenon's injection versus paracetamol in pediatric strabismus surgery

BACKGROUND

Emergence agitation, vomiting, and oculocardiac reflex (OCR) in children undergoing strabismus surgery under general anesthesia are common problems. The purpose of this study was to determine whether the effect of analgesia can reduce the incidence of these problems. We compared the effects of sub-Tenon's injection versus intravenous (IV) and rectal paracetamol in this surgery.

METHODS

In a prospective, randomized, double-blind study, ninety patients ranging in age from 4 to 8 years scheduled for extraocular muscle surgery for strabismus were included in this study. After induction of anesthesia, just before the surgery, children were divided into three groups (n = 30 for each group) Group A received sub-Tenon's anesthesia with 2.5% bupivacaine (0.08 ml/kg). Group B received IV paracetamol (20 mg/kg). Group C received paracetamol rectal suppository (40 mg/kg). The occurrence of oculocardiac reflex (OCR) intraoperatively was recorded. Then, in the Postanesthesia Care Unit, patients were assessed for their emergence behaviors. Vomiting was also noticed.

RESULTS

The OCR developed in few patients, and there was no significant difference between the groups. The highest number of patients with agitation was in Group C followed by Group B then Group A. Vomiting was significantly low in Group A followed by Group B then Group C.

CONCLUSION

Sub-Tenon block in strabismus surgery in children decreased the incidence of postoperative agitation and vomiting compared with IV paracetamol then rectal paracetamol. There was no difference between sub-Tenon block and paracetamol in the incidence of oculocardiac reflex.

[Pediatric perioperative systemic pain therapy: Austrian interdisciplinary recommendations on pediatric perioperative pain management]

BACKGROUND

Many analgesics used in adult medicine are not licensed for pediatric use. Licensing limitations do not, however, justify that children are deprived of a sufficient pain therapy particularly in perioperative pain therapy. The treatment is principally oriented to the strength of the pain. Due to the degree of pain caused, intramuscular and subcutaneous injections should be avoided generally.

NON-OPIOIDS

The basis of systemic pain therapy for children are non-opioids and primarily non-steroidal anti-inflammatory drugs (NSAIDs). They should be used prophylactically. The NSAIDs are clearly more effective than paracetamol for acute posttraumatic and postoperative pain and additionally allow economization of opioids. Severe side effects are rare in children but administration should be carefully considered especially in cases of hepatic and renal dysfunction or coagulation disorders. Paracetamol should only be taken in pregnancy and by children when there are appropriate indications because a possible causal connection with bronchial asthma exists. To ensure a safe dosing the age, body weight, duration of therapy, maximum daily dose and dosing intervals must be taken into account. Dipyrone is used in children for treatment of visceral pain and cholic. According to the current state of knowledge the rare but severe side effect of agranulocytosis does not justify a general rejection for short-term perioperative administration.

OPIOIDS

In cases of insufficient analgesia with non-opioid analgesics, the complementary use of opioids is also appropriate for children of all age groups. They are the medication of choice for episodes of medium to strong pain and are administered in a titrated form oriented to effectiveness. If severe pain is expected to last for more than 24 h, patient-controlled anesthesia should be implemented but requires a comprehensive surveillance by nursing personnel.

KETAMINE

Ketamine is used as an adjuvant in postoperative pain therapy and is recommended for use in pediatric sedation and analgosedation.

Premarketing surveillance of ibuprofen suppositories in febrile children

In many countries, ibuprofen is available only in oral formulations. The authors aimed to investigate parental satisfaction and possible adverse reactions among children receiving newly marketed ibuprofen suppositories, prior to their arrival at the pharmaceutical points of distribution. Children needing antipyretic medication were recruited from 11 pediatric wards and clinics in Israel. Each patient received ibuprofen suppositories (5-10 mg/kg/dose) after completing a data collection form. After 3 to 7 days of treatment, information regarding parent satisfaction, possible adverse reactions, and concomitant use of drugs was obtained. Overall, 490 children completed the study. Parents' satisfaction was high (4.5 ± 0.47 on a scale of 1-5), and 92.2% reported that they would use the medication in the future. Adverse reactions were reported in 8 patients (1.63%, 95% confidence interval = 1.77-3.25), the most common being diarrhea. Rectal administration of ibuprofen suppositories is well tolerated and overall satisfaction and the repeated expected use were high.

Parental calculation of pediatric paracetamol dose: a randomized trial comparing the Parental Analgesia Slide with product information leaflets

OBJECTIVES

To compare the ability of parents to calculate and demonstrate the correct paracetamol (acetaminophen) dose, interval, and frequency for their child when using either product information leaflets or the Parental Analgesia Slide.

BACKGROUND

Prescribing information provided with over-the-counter medication may be a source of confusion for parents delivering analgesics to children at home. Accurate administration is essential to ensure safe and effective treatment of children's pain or fever. The Parental Analgesia Slide is a new device developed with the objective of improving parental dosing accuracy.

METHODS

In this prospective, randomized study, 160 parents accompanying children aged between one and 13 years old were randomly allocated to complete a paracetamol dose calculation and administration questionnaire using one of two sources of prescribing information. Absolute percentage dose error and the number of correct dosage intervals, frequencies, and demonstrated drug volumes were compared.

RESULTS

Use of the Parental Analgesia Slide resulted in a reduction in the absolute percentage dose error from a median of 33.3 to 0% (P < 0.001) and an increase in the number of correct dosage intervals and frequencies (59/80 to 70/80, P = 0.046). There was no difference in the number of correctly demonstrated drug volumes (P = 0.082) despite a greater number of parents opting to use an oral syringe rather than a dosing spoon when using the Slide (24/80 to 44/80, P = 0.002).

CONCLUSIONS

The Parental Analgesia Slide resulted in improved parental ability to calculate paracetamol dose, interval, and frequency while preserving their ability to demonstrate an accurate drug volume.

Acute hepatic failure in an infant caused by acetaminophen (paracetamol) toxicity

A 7-month-old infant developed acute fatal hepatic failure owing to inadvertent duplication of paracetamol prescriptions. Paracetamol toxicity should be considered in the differential diagnosis of infants presenting with acute hepatic failure.

[Systemic analgesia adapted to the children's condition]

A concept of balanced analgesia using nonsteroidal anti-inflammatory drugs (NSAIDs), paracetamol (acetaminophen), opioids, and corticosteroids can also be used in patients with pre-existing illnesses. NSAIDs are the most effective treatment for acute pain of moderate intensity in children; however, these drugs should be avoided in patients at increased risk for serious side effects, e.g. patients with renal impairment, bleeding tendency, or extreme prematurity. NSAIDs can be given with minimal risks to the younger child with mild to moderate asthma, and, in these patients, the use of steroids can be encouraged; in addition to their antiemetic and analgesic action, a beneficial effect on asthma symptoms can be expected. In the non-intubated child with cerebral trauma, exaggerated sedation caused by opioids and increased bleeding tendency caused by NSAIDs must be avoided. In neonates and small infants, the oral administration of sucrose or glucose is helpful to minimize pain reaction during short uncomfortable interventions.

Fulminant hepatic failure and paracetamol overuse with therapeutic intent in febrile children

OBJECTIVE

To evaluate the risk of fulminant hepatic failure in relation to paracetamol overuse with therapeutic intent in febrile children.

METHODS

It was a case control study. Paracetamol ingestion for the current febrile illness was compared between 25 cases of fulminant hepatic failure and 33 hospital age matched controls.

RESULTS

Supra-therapeutic doses of paracetamol (mean 145 mg/kg/day) were consumed by all 25 cases compared to none in the control group. Mean paracetamol level in the cases and controls were, respectively, 26.84 mg /dl and 0.051 mg /dl (p< 0.001). The mean duration of paracetamol intake prior to admission in cases was 3. 45 days compared to 1.85 days in the control group. Nineteen, 5 and 3 were, respectively, graded as hepatic encephalopathy grade 1, 2 and 3. All six patients in grade 2 and 3 had hepatomegaly compared to 78% in the grade 1. Four had jaundice and all were in grade 2 or 3. Mean alanine aminotransferase was 2781 U/L None of the randomly selected cases (6) had serological evidence of Hepatitis A, Hepatitis B or Dengue. Three cases died.

CONCLUSION

Exposure to multiple supratherapeutic doses of paracetamol is a risk factor to develop fulminant hepatic failure in children with an acute viral like febrile illness.

Repeated supratherapeutic doses of paracetamol in children--a literature review and suggested clinical approach

The safety of paracetamol when given in the recommended dosage is well documented. However, in recent years there have been many reports of liver failure associated with repeated exposure to supratherapeutic doses of paracetamol. This paper reviews the literature on chronic supratherapeutic paracetamol exposure in children and the different dosing guidelines. Based on which, we suggest the following approach: liver injury secondary to repeated dosing of paracetamol should be considered when a child has received more than 75 mg/kg/d for at least 2 d, or if risk factors for paracetamol toxicity have been identified. Liver transaminases, coagulation factors, and paracetamol serum concentrations should be measured in these children and in symptomatic children with vomiting, right upper quadrant abdominal pain, and jaundice who have taken paracetamol. Treatment with N-acetyl cysteine should be started regardless of paracetamol concentrations if transaminases or INR are elevated.

CONCLUSION

Liver injury secondary to repeated dosing of paracetamol is rare but may result in severe morbidity and mortality. The cumulative dose of paracetamol should not exceed 75 mg/kg/d. Children treated with higher doses for more than 2 d should be evaluated for possible liver injury and treated with N-acetyl cysteine if evidence of liver injury is found.

Postoperative pain control in children: a guide to drug choice

Postoperative pain in children can usually be well controlled with a combination of analgesics, including acetaminophen (paracetamol), NSAIDs, opioids, and local/regional anesthesia. Recent research has shown that the dosage of acetaminophen required to provide analgesia is higher than the traditional dosages used for the regulation of elevated body temperature. Rectal administration of acetaminophen gives a lower and more variable bioavailability compared with oral administration. There is growing experience with the use of NSAIDs in children and several studies have demonstrated the relatively strong analgesic potential of these drugs. Titration of opioids to analgesic effect, and the use of nurse- and patient-controlled continuous opioid infusions in children have gained widespread use and, with proper education and supervision, are considered excellent methods of pain control. Local peripheral and central blocks decrease the need for anesthetics during surgery and provide effective postoperative pain relief.

The choice of inhalation anaesthetic for major abdominal surgery in children with liver disease

Many children with liver disease undergo major abdominal surgery. Maintenance of anaesthesia is thus an important consideration in this surgical population. Despite a comprehensive and painstaking review of the literature, a sound evidence base, on which a choice of inhalation anaesthetic may be made, is lacking due to limited research in these patients. Differences between the more recent agents such as isoflurane, sevoflurane and desflurane are minor. Sevoflurane is favoured in paediatric practice for gaseous induction, but desflurane or isoflurane are marginally the preferred agents for maintenance of anaesthesia in children with liver disease undergoing major abdominal surgery. However, on the evidence that exists, much of it admittedly in animals and in adults, all three are preferable to halothane in this group of patients. More work is needed in this area before sound conclusions can be drawn and one agent proved to be definitely superior to the others.

Approaches toward repeated supratherapeutic doses of paracetamol in children: a survey of medical directors of poison centres in North America and Europe

BACKGROUND

During the last few years there has been an increase in the number of reports of liver failure associated with prolonged paracetamol (acetaminophen) administration in children for therapeutic reasons.

OBJECTIVE

To describe the approach taken by medical directors of poison centres regarding the treatment of repeated supratherapeutic doses of paracetamol in children.

METHODS

Questionnaires mailed to the medical directors of 76 poison centres in North America and 48 poison centres in Europe asked respondents to comment on the management of a hypothetical case of a child who had received repeated doses of paracetamol at a daily dose of 90 mg/kg during a febrile illness and who presented to the emergency department with mildly elevated serum transaminase levels.

RESULTS

The response rate was 62% for North American centres and 44% for European centres. There was a wide range of answers regarding the maximal safe daily dose of paracetamol. For the case described, 71% of the respondents suggested measuring paracetamol serum concentration. Fifty-four percent suggested treating the patient with acetylcysteine and 35% suggested not treating the patient.

CONCLUSIONS

Our study showed that there is little agreement among medical directors of poison centres on the toxic threshold for chronic exposure to paracetamol in children and on how these cases should be managed.

Protection against acetaminophen-induced liver injury and lethality by interleukin 10: role of inducible nitric oxide synthase

Mechanistic study of idiosyncratic drug-induced hepatitis (DIH) continues to be a challenging problem because of the lack of animal models. The inability to produce this type of hepatotoxicity in animals, and its relative rarity in humans, may be linked to the production of anti-inflammatory factors that prevent drug-protein adducts from causing liver injury by immune and nonimmune mechanisms. We tested this hypothesis by using a model of acetaminophen (APAP)-induced liver injury in mice. After APAP treatment, a significant increase was observed in serum levels of interleukin (IL)-4, IL-10, and IL-13, cytokines that regulate inflammatory mediator production and cell-mediated autoimmunity. When IL-10 knockout (KO) mice were treated with APAP, most of these mice died within 24 to 48 hours from liver injury. This increased susceptibility to APAP-induced liver injury appeared to correlate with an elevated expression of liver proinflammatory cytokines, tumor necrosis factor (TNF)-alpha, and IL-1, as well as inducible nitric oxide synthase (iNOS). In this regard, mice lacking both IL-10 and iNOS genes were protected from APAP-induced liver injury and lethality when compared with IL-10 KO mice. All strains, including wild-type animals, generated similar amounts of liver APAP-protein adducts, indicating that the increased susceptibility of IL-10 KO mice to APAP hepatotoxicity was not caused by an enhanced formation of APAP-protein adducts. In conclusion, these findings suggest that an important feature of the normal response to drug-induced liver injury may be the increased expression of anti-inflammatory factors such as IL-10. Certain polymorphisms of these factors may have a role in determining the susceptibility of individuals to idiosyncratic DIH.

Management of paracetamol overdose: current controversies

Paracetamol (acetaminophen) is one of the most frequently used analgesics, and is the most commonly used substance in self-poisoning in the US and UK. Paracetamol toxicity is manifested primarily in the liver. Treatment with N-acetyl-cysteine (NAC), if started within 10 hours from ingestion, can prevent hepatic damage in most cases. Pharmacokinetic data relating plasma paracetamol concentration to time after ingestion have been used to generate a 'probable hepatoxicity line' to predict which cases of paracetamol overdose will result in hepatotoxicity and should be treated with NAC. However, later studies use a 25% lower line as their 'possible hepatotoxicity line'. Although adopting the original line may save considerable resources, further studies are needed to determine whether such an approach is safe. On the basis of the metabolism of paracetamol, several risk factors for paracetamol toxicity have been proposed. These risk factors include long term alcohol (ethanol) ingestion, fasting and treatment with drugs that induce the cytochrome P450 2E1 enzyme system. Although some studies have suggested that these risk factors may be associated with worse prognosis, the data are inconclusive. However, until further evidence is available, we suggest that the lower line should be used when risk factors are present. In Canada and the UK, the intravenous regimen for NAC is used almost exclusively; in the US, an oral regimen is used. Both regimens have been shown to be effective. There is no large scale study with direct comparison between these 2 therapeutic protocols and controversy still exists as to which regimen is superior. During the last few years there has been an increase in the number of reports of liver failure associated with prolonged paracetamol administration for therapeutic reasons. The true incidence of this phenomenon is not known. We suggest testing liver enzyme levels if a child has received more than 75 mg/kg/day of paracetamol for more than 24 hours during febrile illness, and to treat with NAC when transaminase levels are elevated. Paracetamol overdose during pregnancy should be treated with either oral or intravenous NAC according to the regular protocols in order to prevent maternal, and potentially fetal, toxicity. Unless severe maternal toxicity develops, paracetamol overdose does not appear to increase the risk for adverse pregnancy outcome.

The analgesic efficacy of preoperative high dose (40 mg x kg(-1)) oral acetaminophen after bilateral myringotomy and tube insertion in children

BACKGROUND

The purpose of this study was to measure the plasma levels and analgesic effectiveness of a dose of 40 mg x kg(-1) of preoperative oral acetaminophen.

METHODS

Thirty children aged 55 (17-72) months undergoing bilateral myringotomy and tube insertion (BMT) received acetaminophen 40 mg x kg(-1) p.o. preoperatively. Plasma levels were measured, at 29 (10-51) min and at 60 min in the postanaesthesia care unit (PACU). Children's Hospital of Eastern Ontario Pain Scale (CHEOPS), for all subjects and the Poker Chip Tool (PCT) a self-report scale for subjects aged > 4 years, were used. After discharge, 24-h analgesic efficacy was evaluated using an observer Visual Analogue Scale (VAS) score and further acetaminophen use was recorded.

RESULTS

Plasma concentrations were 259 (60-391) micromol x l(-1) and 250 (135-450) micromol x l(-1), respectively. All 60 min plasma concentrations were > or = 70 micromol x l(-1) (ED50 for adenotonsillectomy) and less than 800 micromol x l(-1) (associated with toxicity). Twenty-six subjects (87%) had adequate analgesia (CHEOPS < or = 8). The PCT was only understood in the PACU by 13 of the 21 children > 4 years (62%). The median worst 24-h observer VAS was 0.5 (0-5.5) (27 subjects). No further analgesic was required after discharge in 16/28 (57%). A higher plasma level was associated with fewer doses of acetaminophen after discharge (r = -0.36, P=0.05).

CONCLUSIONS

No relationship was evident between age, the 60 min plasma acetaminophen level and the CHEOPS carried out at the same time. Acetaminophen 40 mg x g(-1) p.o. results in 60 min plasma levels of 250 (135-450) micromol x l(-1). The in-hospital analgesic efficacy was 87% (CHEOPS < 9, no further analgesics) and the 24-h efficacy was 57% (need for further acetaminophen).

Postoperative pain management in infants and children: new developments

The elimination of pain should be of outstanding importance for all people caring for children. A concept of balanced analgesia including non-steroidal anti-inflammatory drugs, opioids and local anaesthetics is widely accepted. This review focuses on extending analgesia beyond the immediate postoperative period, the understanding of pharmacokinetic-pharmacodynamic interactions of paracetamol, the side-effects of opioids during patient-controlled administration, and the position of ropivacaine in paediatric pain management. For the majority of clinical situations, however, we already have established and functioning concepts for analgesia; we only have to use them!