Opioid-Related Critical Care Resource Use in US Children’s Hospitals

Discussion

We present the first study of the impact of the current US opioid crisis on the pediatric critical care community using a national sample of patients who were admitted to major pediatric hospitals. In this study, we demonstrate a significant and steady increase in the diagnosis of opioid ingestion and poisoning across all age groups in US children’s hospitals from 2004 to 2015. Not only did the absolute number of opioid-related admissions increase but the rate of both hospital and PICU admissions increased as well. The opioid-related hospital admission rate increase of 39% is substantial as is the 35% increase in the rate of PICU admissions for opioid-ingestion. This increase in PICU use parallels the increase in hospital admissions and is consistent with previously published data that reveal an increase in the annual incidence of hospitalizations and ED encounters for opioid poisoning in children.^7,9

The percentage of PICU patients requiring mechanical ventilation decreased over time, from nearly half of PICU admissions to only one-third. The percentage of PICU admissions for opioid ingestion requiring vasopressors also fell by nearly half. However, because of the increase in the number of patients with opioid-related hospitalizations requiring PICU care across the study period, the absolute number of patients with opioid ingestion requiring mechanical ventilation and vasopressors increased over time. The median cost of care decreased significantly during the study period, likely because of a shorter overall hospital length of stay. However, because of the increases in all hospitalizations and those hospitalizations requiring critical care for opioid ingestion, the actual overall financial burden on the health system increased. Additionally, the total number of hospital days that were attributed to patients with opioid ingestion and the total number of patients requiring mechanical ventilators and/or vasopressors continue to increase over time at an alarming rate.

The only other data that reveal the impact of the US opioid crisis on critical care resource use are from the adult population.¹⁰ Stevens et al¹⁰ found that there was a marked increase in critically ill adult patients who were admitted to the ICU with overdoses from opioids between 2009 and 2015, with an increase in mortality and a near doubling of ICU deaths. In addition, the total cost of care increased by 58% in the adult ICUs over that same period. In contrast, although the total number of pediatric patients admitted to the PICU has also increased significantly, the pediatric health care system has become more efficient, with lower lengths of stay per hospitalization, less mechanical ventilation per hospitalization, less vasopressor use per hospitalization, and reduced mortality over time. The underlying cause of the difference between adult and pediatric critical care outcomes is likely due to the difference in the opioid class leading to hospitalization. In this study, methadone and other opioids were the major contributors to pediatric hospitalization, whereas in the adult study, heroin was shown to be the key driver to adult ICU hospitalization and mortality. Adult heroin users are likely to have a number of clinical comorbidities that may contribute to their increased cost of care. Additionally, illicit heroin can be contaminated with other opioid and nonopioid substances that may make its use more lethal compared with regulated prescription drugs, such as methadone.

The increasing number of adult drug prescriptions is strongly associated with rising pediatric exposures and poisonings; young children are at the greatest risk for exposure, with substantial health care use and morbidity specifically associated with opioid ingestions.⁶ The exploratory nature of young children makes them particularly vulnerable to harm from accidental medication ingestions as opposed to adolescents and teenagers, who are more likely to have intentional ingestions, including for recreational purposes or for self-harm.^5,15 We identified methadone ingestions, in particular, as an important driver for hospital care, with nearly 20% of children <6 years of age being admitted with methadone ingestion. From 2000 to 2007, the US Drug Enforcement Administration data showed a 559% increase in prescriptions for methadone; these data help to inform the findings in this study.⁸ Additionally, data from the American Association of Poison Control Centers revealed that methadone was responsible for 24.9% of serious medical outcomes in all patients who are admitted to health care facilities, which is consistent with our finding of 20%.⁷

Insurance coverage for the majority of pediatric patients in this study who were hospitalized with opioid ingestion was provided by Medicaid. The percentage of patients with opioid ingestion who have Medicaid as the primary payer source has increased over time. Additionally, 66.5% of patients <6 years of age were covered by Medicaid. In the current health care climate, in which proposed changes to the funding of state-based Medicaid programs is under consideration, any reduction of Medicaid funding could have a profound impact on the ability to recuperate the cost of acute hospital care that is associated with pediatric opioid ingestions.

There are a number of limitations to this study. First, the PHIS database offers the unique advantage of detailed, national-level, pediatric data from the majority of US metropolitan areas. The PHIS provides up to 21 diagnosis codes per hospitalization and provides more diagnostic data per patient than most administrative data sets. However, the data provide an unweighted convenience sample because member hospitals change over time. To control for this, only those data from member hospitals that enrolled patients throughout the entire study period were included. Additionally, the data may not be generalizable to nontertiary-care, nonchildren’s hospitals. For example, because of referral bias, the PHIS may overrepresent the true incidence of opioid ingestions requiring PICU care. Also, because the PHIS data represent ∼20% of all pediatric hospitalizations in the United States, the total cost burden to the US health care system is clearly understated. Second, case identification is dependent on ICD-9-CM codes, which, like all administrative data, rely on accurate coding. Errors of both miscoding and the omission of key codes may occur. However, the search strategy used in this study has now been employed in a number of publications and has previously been validated in the literature. Additionally, validation studies involving other common medication poisonings support the use of ICD-9-CM codes for the identification of hospitalizations for medication toxicities in children.¹⁶ Because of the limitations of the ICD-9 and ICD-10 coding system, the identities of the specific opioids ingested are unknown. It is possible that other data may better inform which specific agents are key drivers to pediatric hospitalization and PICU resource use, and they may provide targets for strategic public health initiatives.

The current US opioid crisis is negatively impacting pediatric patients as the rate of hospitalization and PICU care for the ingestion of opioids by children continues to increase over time. With higher volumes of patients being admitted to the PICU because of opioid ingestion, the overall use of pediatric critical care resources, including mechanical ventilation and vasopressors, has increased over time, although efficiencies in both life-sustaining interventions and the total cost of care per patient have improved. Current efforts to reduce prescription opioid use in adults have not curtailed the incidence of pediatric opioid ingestion, and additional efforts are needed to reduce preventable opioid exposure in children.