Introduction

Health expenditures, including laboratory tests, are gradually increasing worldwide [1], and the cost-effective use of medical laboratories has become a much-debated subject. Ordering a large number of unnecessary tests in the diagnosis and follow up of patients increases costs, and also uses up valuable workforce time, which may lead to failure to notice actual illnesses because of increased workload. This subject has emerged as an important concern in the world, and various solutions have been discussed. The cost of unnecessary testing amounts to billions of dollars in the United States [2]. There are many studies in the literature regarding the regular use of laboratory tests and attempts to reduce laboratory expenditures [3,4]. Studies into changing the habits of clinicians on the use of laboratory tests have followed different strategies, and the information technology (IT) departments of hospitals have come up with instructions such as “Best Practice Advisories” to prompt users to order only rational tests. Monitoring laboratory usage and informing clinicians about laboratory costs decrease the number of test orders, and there have been various studies that support the training of clinicians in good laboratory practices that have played an important role in changing habits [5,6].

In seeking to avoid the increasing number of malpractice lawsuits which can result in substantial indemnity payments, clinicians have tended towards ordering more tests than necessary, so as not to overlook any illnesses [7]. Studies to date have reported on efforts to avoid unnecessary testing in the preanalytical phase through informative training programs, warning messages, and suggestion prompts when tests are being ordered. Recently introduced artificial intelligence software programs have led to the prevention of the use of certain tests in the analytical phase, and such programs have been created for ordering additional, related tests. Commercial kit manufacturers introduced artificial intelligence programs into the market to boost their sales by reducing test orders that do not match up with the kit policies. However, it is possible to use these programs contrary to their manufacturers’ purpose. The use of artificial intelligence programs to prevent the ordering of unnecessary tests in the analytical phase may prevent the ordering of tests that have become a regular practice, thus saving billions of dollars.

Artificial intelligence programs have been used widely to prevent the ordering of related tests in the analytical phase. AST is one such test, which is commonly used to screen for liver diseases; its levels increase correspondingly with ALT levels [8,9]. There are only a very few conditions under which ALT is found to be within normal ranges and where AST is elevated above the normal limits, hemolysis being the most common of those [10]. An AST test order should be rejected in hemolytic samples because if the test is carried out, the result would not be significant and would result in unnecessary costs [11]. Parenteral injections are another factor that affects AST levels, while muscle disease is an important condition in which AST is affected, but ALT is not [12]. Creatine kinase (CK) should also be used in conditions, such as AST, and can be found in places other than the muscle. Hence, orders for AST tests could be canceled in the analytical phase when ALT is found to be normal. Total bilirubin levels increase in liver diseases and bile duct obstruction [13], and this is used in conjunction with direct bilirubin during diagnosis. Direct bilirubin testing makes no sense if total bilirubin is normal. Thus, it would be appropriate to cancel the test order in the analytical phase. Total PSA levels are increased in many prostatic diseases and operations [14] Free PSA testing makes no sense if the total PSA is normal, and so its use can be canceled in the analytical phase. The main focus of the present study is to demonstrate the effectiveness of artificial intelligence programs in the avoidance of tests in the analytical phase.

Material and Method

This study was conducted using data obtained from certain tests using the ALIN IQ software developed by Abbott Core Laboratory, which can implement the algorithms defined by the information management system of the hospital. AST, direct bilirubin, and free PSA were the only blocked tests. The software was set to run ALT, total bilirubin, and total PSA as the preferences when ordered by a clinician along with other tests sent to the c16000 biochemistry analyzer. All AST tests for patients with normal ALT values in the analysis, direct bilirubin tests for patients with normal total bilirubin values, and free PSA tests for patients with normal total PSA values were canceled. AST, direct bilirubin, and free PSA tests were only run if the results of the other tests were outside normal limits. The mean number of AST, ALT, total bilirubin, direct bilirubin, total PSA, and free PSA tests run per month, and AST/ALT, direct bilirubin/total bilirubin, and free PSA/total PSA ratios before and after the use of ALIN IQ software were calculated, and the differences in the number of AST, ALT, total bilirubin, direct bilirubin, total PSA, and free PSA tests and differences in AST/ALT, direct bilirubin/total bilirubin, and free PSA/total PSA ratios before and after the use of ALIN IQ software were calculated, with the magnitude of change recorded separately.

Results

In this study, 14,667 ALT tests and 13,888 AST tests were run in a one-month period before the use of ALIN IQ software. After the ALIN IQ software was deployed, 16,445 ALT tests and 2,751 AST tests were run over a one-month period (Figure 1). Before the use of ALIN IQ software, the AST tests corresponded to 94.68% of all ALT tests. The use of ALIN IQ software eliminated 77.96% of unnecessary AST tests, with the total number of AST tests corresponding to only 16.72% of the ALT tests (Figure 2).

Before the use of ALIN IQ software, 9,243 total bilirubin and 9,184 direct bilirubin tests were run in a one-month period. After the ALIN IQ software was deployed, 10,512 total bilirubin and 2,328 direct bilirubin tests were run over a one-month period (Figure 1). Before the use of ALIN IQ software, direct bilirubin tests corresponded to 99.36% of the total bilirubin tests. The use of ALIN IQ software eliminated 77.22% of unnecessary direct bilirubin tests, with the total number of direct bilirubin tests corresponding to only 22.14% of the total bilirubin tests (Figure 2).

Before the use of ALIN IQ software, 1,870 total PSA and 1,820 free PSA tests were run in a one-month period. After the ALIN IQ software was deployed, 1,930 total PSA tests and 480 free PSA tests were run over a one-month period (Figure 1). Before the use of ALIN IQ software, free PSA tests corresponded to 97.32% of the total PSA tests. The use of ALIN IQ software eliminated 72.45% of unnecessary free PSA tests, with the total number of free PSA tests corresponding to only 24.87% of the total PSA tests (Figure 2).

The software provided savings of 11,137 (77.96%) AST tests, 6,856 (77.22%) direct bilirubin tests, and 1,340 (77.45%) free PSA tests in a one-month period (Figures 3 and 4), corresponding to projected savings of 133,644 AST tests, 82,272 direct bilirubin tests, and 16,080 free PSA tests over the course of a year. In a laboratory that runs 2,444,024 tests per year, ALIN IQ software provided an projected saving of 231,996 tests by blocking the ordering of three unnecessary tests. The amount of savings corresponds to 9.49% of the total number of tests ordered.

Discussion

Inappropriately ordered laboratory tests represent a problem that arises from several possible reasons that have been widely discussed in the literature [15,16]. Given that all physicians undergo medical education in tertiary healthcare facilities at which extensive laboratory workup is performed, defensive medicine, fear of involvement in malpractice cases, lack of laboratory history, lack of sufficient knowledge among doctors, and patient pressure are among the reasons that unnecessary tests are ordered [17,18]. Billions of dollars are spent on unnecessary tests and medical supplies in the United States [19], and various methods have been developed to prevent unnecessary testing costs and to improve test usage to address this global problem. The most commonly employed methods tend to focus on the preanalytical phase [20].

In a meta-analysis by Solomon et al., informing clinicians, auditing laboratory usage, and sharing information on laboratory costs with clinicians were suggested as effective methods to change habits in the use of laboratory services [21]. In another study, the effects of cost education, cost auditing, and the use of clinical cards were compared in their efficiency to reduce the quantity of ordered laboratory tests, and use of clinical cards was found to be the most effective method [22]. In the United States, new health policies support the allocation of resources to the comparative effectiveness studies and to prepare “evidence-based guidelines” to decide which tests or therapies are superior [23]. Education and feedback would be important components in adherence to these guidelines [24].

In a model tested in a private hospital, a hospital information system that allowed clinicians to order tests online was re-arranged to prompt the correct use of laboratory tests. In this model, reminders referred to as “Best Practice Advisories” were integrated into the system, with advice determined by a committee established in the hospital to direct clinicians during the ordering of tests. Warning messages are generated. For example when ordering HBsAg, the warning, “Please make sure that the patient did not have a hepatitis vaccine shot in the last two weeks” is given, or in the case of a repeated test, the warning, “You are ordering the same test for the second time” is given [25].

Test ordering habits could be changed through training of clinicians [26]. As part of this training, ways to limit the ordering of certain tests and to change test ordering habits have been suggested [27]. In another study that compared methods of informing clinicians, no feedback was provided to one group of clinicians; feedback was provided to a second group regarding their laboratory usage habits; for a third group, a document regarding the cost-effective use of laboratory testing was provided; while a fourth group received feedback about their own laboratory usage habits and the cost-effective use of the laboratory. The highest cost reduction, amounting to 42%, was noted in the fourth group [28].

A “Computerized Clinician Order Login Screen” has been used to alert clinicians regarding the implementation of targeted strategies. Daily routine laboratory test order panels prepared by the clinicians (routine biochemistry, calcium/phosphor/magnesium, and complete blood count) constitute the majority of test orders in inpatient cases. The system requires an explanation from the clinician when making repeat test orders within a three-day period. Thus, test orders could be limited. In one study, the use of this method was found to reduce test orders by 24% in inpatient cases [29].

Modifications to the login screens used by clinicians are another method that has been investigated. In one study, redundant tests with limited clinical efficacy were removed from the quick order screen, making the ordering of such tests more difficult. For example, lactate dehydrogenase (LDH) is found to be abnormal in many conditions and it provides similar results to creatine kinase and transaminases tests. Removal of the LDH test from the order entry screen via a quick scan has resulted in an approximate 50% reduction in unnecessary LDH orders for inpatients [30].

Controlling ordering frequency is another proposed method. In one study of intensive care unit patients, the ordering of complete blood counts, biochemistries, and coagulation tests more than once in a 24-hour period was blocked, and this was reported to reduce order numbers without causing any side effects or affecting discharge times [31].

Relentless strategies, such as blocking laboratory tests at the time of order, are undesirable because they restrict the clinicians’ freedom and may lead to concerns that conditions may not be diagnosed in time. Blocking tests that are related to each other in the analytical phase would not raise any objections because it would not restrict the clinicians’ freedom. A literature review showed that preanalytical variables and measures have been the subject of previous studies. However, to our knowledge, there are no studies to date that aimed to reduce the number of unnecessary tests ordered in the analytical phase. In this regard, this research is the first study of its kind in the literature.

In this study, for the first time in the literature, an attempt was made to avoid unnecessary tests being ordered in the analytical phase by defining algorithms described in the method sections for ALIN IQ software, developed by Abbott Core Laboratory, for use in the clinical biochemistry laboratory of the Harran University Training and Research Hospital. In proportion to the total number of test orders, ALIN IQ achieved a 77.96% reduction in AST tests, a 77.22% reduction in direct bilirubin tests, and a 72.45% reduction in free PSA tests (Figure 4). In a laboratory that runs 2,444,024 tests per year, the ALIN IQ software provided projected savings of 231,996 tests by blocking the ordering of three different and unnecessary tests. The savings corresponds to 9.49% of the total number of tests ordered. ALIN IQ and similar software programs may provide more savings in hospitals with a high patient load. Furthermore, these software programs, in addition to providing cost savings, can also calculate daily test averages and will prompt users if systematic errors are detected. Also, they can detect any calibration shifts that may occur during the day. The Delta check feature also permits the detection of significant differences between previous and current test results in patients in the validation phase, while the automatic validation of normal test results may reduce waiting times.

Conclusion

This study has shown that software programs can provide significant savings in routine clinical biochemistry laboratories. Algorithms that aim to eliminate unnecessary tests can be used for hepatitis markers, expensive immunoassays, and PCR tests, in addition to biochemistry. ALIN IQ and similar smart software programs do not depend on the device brand and can be adapted to any analyzer capable of the data transfer. The use of such software programs in diagnostic laboratories with high workloads can be considered a cost-effective approach given that their costs are lower than the savings they achieve.

Scientific Responsibility Statement

The authors declare that they are responsible for the article’s scientific content including study design, data collection, analysis and interpretation, writing, some of the main line, or all of the preparation and scientific review of the contents and approval of the final version of the article.

Animal and human rights statement

All procedures performed in this study were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. No animal or human studies were carried out by the authors for this article.

Funding: None

Conflict of interest

None of the authors received any type of financial support that could be considered potential conflict of interest regarding the manuscript or its submission.

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Introduction

Poisoning is one of the most commonly encountered medical emergencies and is a common reason for emergency department visits and admissions to the intensive care unit. In 16 countries with high or medium income levels, poisoning was identified as the fourth leading cause of unintentional injury following motor vehicle accidents, fires, and drowning [1].

Poisoning is also the second leading cause of injuries requiring hospitalization in children younger than 5 years [2]. The mortality rate varies based on the causative agent, the dose, and patient characteristics [3].

Identifying clinical characteristics of patients admitted with a diagnosis of poisoning may contribute to the development of appropriate treatment measures. We identify clinical characteristics of patients admitted to the pediatric intensive care unit (PICU) with a diagnosis of poisoning as well as the frequencies of the chemical agents involved in the poisoning and the antidotes used.

Material and Method

This was a retrospective, single-center, cross-sectional study. All patients who were admitted to the PICU of Kayseri Training and Research Hospital between December 2012 and June 2017 for poisoning by a chemical substance were included in the study. The PICU of Kayseri Training and Research Hospital consists of 22 ICU beds, including 12 Level 3 and 10 Level 2 beds. The annual volume is approximately 340 patients.

The study was approved by the Clinical Research Board of Erciyes University School of Medicine (approval no. 2017/135). The study was exempted from obtaining patient consent because it was a retrospective study.

Eligibility criteria included age <18 years and admission to the PICU with a diagnosis of poisoning. Exclusion criteria included poisoning due to food or animals (e.g., a scorpion or snake bite). The diagnosis was made based on information obtained from the patient or caregivers regarding any history of ingestion of suspicious chemicals and clinical signs and symptoms.

Data were extracted from patient records and intoxication data sheets completed for all patients with chemical poisoning. Data regarding age, sex, body weight, dates of PICU admission and discharge, reason for ingestion (unintentional, suicidal intent, substance abuse), previous history of suicide attempt, history of psychiatric therapy, drugs ingested and their doses, presence or absence of gastric lavage and/or active charcoal administration, route of intake (oral, intravenous, inhalation), Pediatric Risk of Mortality (PRISM) and Glasgow Coma Scale (GCS) scores at presentation, administration of any antidote, use of mechanical ventilation, clinical and laboratory findings, and mortality were recorded on the intoxication data sheet.

The primary aim of this study was to determine agents that lead to poisoning in patients admitted to the PICU with a diagnosis of poisoning by a chemical substance. Secondary aims were to determine the frequency of admissions due to poisoning; the demographic, clinical, and laboratory findings of patients; the antidotes used; and the mortality rate. Data are presented as frequencies (%).

All statistical analyses were performed using IBM Statistics for Windows version 21.0. Normality was tested using the Kolmogorov–Smirnov test. Nonparametric data are presented as medians (25th–75th percentiles). Categorical data are presented as frequencies (%). A p-value <0.05 was considered to indicate statistical significance.

Results

Overall, 1093 patients were admitted to the PICU during the study period (December 1, 2012–June 1, 2017), including 223 patients with poisoning by chemical substances. The incidence of admissions to the PICU due to poisoning was 11.7%. During the same period, 1139 patients presented to the emergency department with poisoning by a chemical substance, but only 223 (19.57%) of these were admitted to the PICU.

In this study population, the median age was 154 (30–193) months, and the median body weight was 35 (13–54.7) kg. There were 131 girls (58.7%) and 92 boys (41.3%). The median age was 183 (143–195) months in girls and 40 (24–176) months in boys; it was 37 (25–63) months in patients with unintentional poisoning and 186 (178–198) months in patients who had attempted suicide (p < 0.001).

The GCS score at presentation was <8 in 12 (5.38 %) patients, 8–14 in 17.5%, and 15 in 77.1% (n = 172). The median PRISM score was 0 (0–8). The median length of ICU stay was 1 (1–2) day.

Poisoning was unintentional in 130 (58.3%) patients. It was associated with suicidal intent in 89 (39.9%) and with substance use in 4 (1.8%) of patients. Of all patients, 33 ( 14.8%) were receiving psychiatric therapy at the time of admission.

Of those diagnosed with poisoning accompanied by suicidal intent (n=89), 29 (32.6%) were receiving psychiatric therapy, 15 (16.9%) had at least one prior suicide attempt, and 19 (21.3%) had ingested prescribed medication in the suicide attempt.

Intake of multiple drugs was identified in 65 (29.1%) and intake of a single drug in 145 (65%); no information regarding the number of drugs taken was available for 13 (5.8%) of the study population. The rate of intake of multiple drugs was 46 (51.7%) among patients with suicidal intent compared to 22 (16.9%) among those with unintentional poisoning (p < 0.001).

The route of intake was oral in 214 (96%) of patients, inhalation in 7 (3.1%), and intravenous in 1 (0.4%). In 13 (5.8%) patients, no information was available on the causative agent, although a history of the poisoning event was taken. No gastric lavage was performed in 204 (91.5%) of patients, and no active charcoal administration was performed in 199 (89.2%). Of the study population, 4 (1.79%) required mechanical ventilation. Mechanical ventilation support was needed because of laryngeal edema from anti-lime intake in one patient, shock, and multiple organ failure due to colchicine and iron intoxication in two patients, and myocarditis and cardiac arrest due to lighter fluid inhalation in one.

Overall, three patients 3 (1.3%) died, including one patient who died from cardiopulmonary arrest caused by lighter fluid inhalation, one patient who died from hepatic and renal failure caused by massive oral iron intake, and one patient who died with multiple organ failure caused by colchicine intoxication.

Three patients 3 (1.3%) were transferred to another facility for treatment, including one patient who required plasmapheresis and two who required hyperbaric oxygen therapy.

Evaluation of the drugs that resulted in intoxication revealed 352 agents. The combination of an analgesic plus an antitussive plus a decongestant (7.7%; n = 27) was the most common agent resulting in intoxication, followed by paracetamol (6.8%; n = 24) and nonsteroidal anti-inflammatory drugs. The drug classes included CNS agents (23.3%), cardiovascular agents (15.6%), environmental poisons (3.4%), pesticides (2.3%), narcotics (1.1%), and analgesic-antipyretic agents and other pharmaceuticals (54.3%). Table 1 lists the drugs that resulted in intoxication in the study population.

An antidote was used in 17.5% of cases, with N-acetyl cysteine being the most commonly used antidote. Table 2 presents the antidotes used.

No clinical or laboratory findings were seen in 161 (72.2%) of patients, whereas both clinical and laboratory findings were observed in 14 (6.3%). Clinical findings alone were identified in 22 (9.9%) of patients, and laboratory findings alone were identified in 26 (11.7%). Table 3 shows the clinical and laboratory findings.

Discussion

In the present study, PICU admissions for poisoning by chemical substances showed the following characteristics: Such poisonings were frequent, unintentional intoxication was the most common form of poisoning, an analgesic–antitussive–decongestant combination was the most common agent, N-acetyl cysteine was the most commonly used antidote, unintentional poisoning was more common among boys and adolescents, colchicine intoxication was more prevalent than previously reported in the literature, most cases had an asymptomatic course, the most common findings in symptomatic patients were cardiovascular in nature, and mortality was rare.

Poisoning is a significant cause of PICU admission and an important health issue in childhood. In ICUs, 5–30% of beds are used for poisoning cases [4]. In our study, 11.7% of ICU admissions were for poisoning by chemical substances.

Age and sex are the most important factors influencing the pattern of poisoning [4]. Poisonings are mostly unintentional, and they are more common in boys than in girls before adolescence. In girls, they are more commonly associated with suicidal intent during adolescence [5, 6].

A study by Andiran et al. [7] found that poisoning due to therapeutic errors was most common in children aged <1 year, unintentional intake was most common in children ages 1–5 years, and intake with suicidal intent was most common in children aged >10 years. A study by Ozdogan et al. [8] found that poisoning was most frequent between 13 months and 4 years of age. In agreement with the literature, the present study found that poisoning with suicidal intent was more common in adolescence and among girls, whereas unintentional poisoning was more common in boys and preadolescents.

In a study in Diyarbakır Province, Ozdogan et al. [8] found that unintentional poisoning was the most common cause of intoxication among cases presenting at the emergency department. Similarly, unintentional intake was the most common cause of poisoning in our study. No poisoning due to misuse of a therapeutic dose was observed in our study. In addition to poisoning with suicidal intent, we also observed cases of poisoning due to substance abuse among adolescents. Poisoning with suicidal intent was more frequent in adolescents and showed a higher incidence in patients with psychiatric risk factors [9]. In our study, of patients diagnosed with poisoning with suicidal intent, 32.6% were receiving psychiatric therapy, 16.9% had at least one prior suicidal attempt, and 21.3% had ingested prescription medication in the suicide attempt. Thus, when considering prescribing psychiatric treatment, one should keep in mind that patients may attempt to poison themselves using prescription medication.

It has been reported that multiple drugs are ingested in the majority of poisoning cases [9]. However, intake of a single drug was observed in the majority of our patients. Intake of multiple drugs was more frequent in cases of poisoning with suicidal intent.

Studies by Ozdemir et al. [3] and Andiran et al. [7] found that analgesics were the most common drugs causing intoxication. In agreement with the literature, an analgesic–antitussive–antipyretic combination, paracetamol, and nonsteroidal anti-inflammatory drugs were the most common agents of intoxication in our study. Among CNS agents, antipsychotic agents were the leading cause of intoxication, followed by SSRIs and tricyclic antidepressants.

Colchicine intoxication is a rare and fatal form of poisoning. According to data from the American Association of Poison Control Centers, the incidence of colchicine intoxication is 0.0046% among children aged <19 years [10]. In our study, colchicine intoxication was observed in 3.4% of the patient population, a markedly higher rate than reported in the literature. This may be because of the higher incidence of Familial Mediterranean Fever in Turkey, for which colchicine is a common treatment.

In a study of patients who presented to the emergency department with poisoning in Eskisehir Province, Sahin et al. [11] reported that the incidence of corrosive agent ingestion was 21.3%, and carbon monoxide intoxication was the third leading cause of poisoning. In our study, the frequencies of corrosive agent ingestion and carbon monoxide intoxication were both low. This may be because of the practice of admitting only children with the potential for severe complications who require close monitoring to the ICU and admitting the majority of cases with corrosive agent ingestion or carbon monoxide intoxication to a regular ward.

In Turkey, volatile substances are the most commonly abused substances after alcohol and cigarettes because they are readily available, inexpensive, and fast acting [12]. In our study, two adolescent patients were admitted to the ICU for lighter fluid inhalation (butane). One of these patients died from myocarditis.

Another readily available environmental toxin is firework cracker, a kind of toy that contains yellow phosphorus, which can result in fatal poisoning. Yellow phosphorus is a potent local and systemic toxin that causes injury to the gastrointestinal system, liver, cardiovascular system, and kidneys [13]. Unfortunately, firework cracker is readily available to children in Turkey. Our study population included two cases of poisoning caused by firework cracker. No impairment in clinical and laboratory parameters was observed in these patients during follow-up.

Currently, gastric lavage is not routinely recommended in poisoning cases. It may be considered only within the first 60 min after ingestion and in cases in which a potentially life-threatening amount of poison has been ingested [9, 14]. Because a broad spectrum of indications is used for gastric lavage in our hospital, gastric lavage was used in all patients except those with hydrocarbon or heavy metal poisoning. This may be because clinicians were concerned about legal liability if they did not use gastric lavage.

Antidotes are available for a limited number of substances causing intoxication, and timely administration of an appropriate antidote improves the clinical picture. However, many centers have problems with their supplies of antidotes [15]. In a study by Andiran et al. [7], an antidote was administered to 7.9% of patients who presented with poisoning. In our study, an antidote was given to 17.5% of patients, the most common being N-acetyl cysteine. Furthermore, antidotes were used in all poisonings for which they were indicated, and several antidotes were used without encountering any problems with supply.

Childhood poisoning cases may show an asymptomatic course, or minor symptoms may be observed [16]. In our study, the majority of patients were asymptomatic (69.5%). The most common clinical findings included hemodynamic abnormalities and cardiac conduction and rhythm disorders, followed by gastrointestinal findings. A shorter ICU stay was associated with high GCS and low PRISM scores at presentation as well as an asymptomatic course.

The mortality rate is low in cases of poisoning, and mortality is more commonly reported in children aged <6 years [6]. In a study of emergency department patients, Andiran et al. [7] reported a mortality rate of 0.4%. In our study, only three patients did not survive; one patient with disseminated intravascular coagulation caused by massive iron intoxication, one with multiple organ failure caused by colchicine intoxication, and one with myocarditis and cardiopulmonary arrest caused by lighter fluid inhalation. Colchicine intoxication is one of the most severe forms of poisoning, and doses of colchicine >0.8 mg/kg are considered lethal [10]. In Turkey, colchicine is marketed in 0.5 mg tablets and sold in cartoon blister packaging. Unintentional intoxication is frequent in younger children, as colchicine is commonly used to treat familial Mediterranean fever and is marketed without safety packaging. In our study, a 3-year-old girl ingested colchicine at a dose >0.8 mg/kg. The rapid development of multiple organ failure and collapse was observed, eventually resulting in death despite plasmapheresis.

A study by Ozdemir et al. [3] found that mortality was higher in cases of poisoning with a nontherapeutic substance compared to poisoning with medication. In our study, no mortality was observed in patients intoxicated by chemical substances except one patient poisoned by lighter fluid. Ingestion of highly alkaline or acidic substances is a major cause of morbidity and mortality worldwide, particularly in developing regions [17]. In our study, a 3-year-old girl unintentionally ingested anti-lime solution. Respiratory arrest and subsequent cardiac arrest developed due to laryngeal edema, and the patient required mechanical ventilation via tracheostomy.

Limitation of the study is the retrospective design and the low number of the patients.

In conclusion, admission to the PICU for intoxication with chemical substances is rather frequent. Although the majority of patients are asymptomatic, mortality is not rare. Understanding the clinical characteristics of patients admitted to the ICU for poisoning is beneficial to the process of establishing appropriate treatment measures.

Acknowledgements

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Scientific Responsibility Statement

The authors declare that they are responsible for the article’s scientific content including study design, data collection, analysis and interpretation, writing, some of the main line, or all of the preparation and scientific review of the contents and approval of the final version of the article.

Animal and human rights statement

All procedures performed in this study were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. No animal or human studies were carried out by the authors for this article.

Funding: None

Conflict of interest

None of the authors received any type of financial support that could be considered potential conflict of interest regarding the manuscript or its submission.

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