Incidence of and Factors Associated With Prolonged and Persistent Postoperative Opioid Use in Children 0-18 Years of Age.

Edition:

Ward A, De Souza E, Miller D, et al. Anesth Analg. 2020;131(4):1237-1248

Study summary:

This is a retrospective cohort study from the USA using de-identified data from one of their national insurance provider’s administrative claims database, spanning 15 years (2002-2017).  The study attempted to look for incidence and factors associated with prolonged (≥1 opioid prescription filled in the 90-180 days after surgery, “POUS”) and persistent (≥60 days of opioid prescriptions filled in the 90-365 days after surgery, “PPOU”) opioid use after surgery, among children aged 0-18 years old.

The study sample size is 173,388 patients from a total of 11,262,713 patients aged 0-18 found from the database, and categorised into 4 age groups: 0 to <2 years (14,684), 2 to <6 years (42,467), 6 to <12 years (47,545) and 12 to 18 years (68,692).

  1. Inclusion criteria:
  2. Underwent at least 1 of the 20 most common surgery types within their respective age group
  3. Opioid naïve (not having filled an opioid prescription in the 90 days before surgery). Opioids included are opiate agonists and partial agonists, but excluded opiates used in cough suppressants
  • Filled an opioid prescription from 30 days before surgery to 14 days after surgery
  1. Had a general anaesthesia recorded within 1 calendar day of the recorded surgical code
  2. Enrolled in the insurance scheme for at least 1 year before surgery and remain enrolled for at least 1 year after surgery for age 2-18
  3. Remain enrolled for at least 1 year after surgery for age 0-<2
  4. Exclusion criteria:
  5. No anaesthesia given
  6. Had a general anaesthesia claim either in the 3-365 days before surgery date, or in the 3-365 days following surgery.
  • Surgery date fell within a hospital stay that exceeded 30 days

 

The study control group (reference baseline incidence of opioid use) consisted of random sampling of 25% patients in 4 age groups that did not have surgery, and they were then randomly assigned a fictitious surgery date.   The control group inclusion criteria are otherwise matched to the study group in terms of being opioid naïve and insurance scheme enrolment, and the exclusion criteria are patients that had a general anaesthesia claim either in the 1 year before their fictitious surgery date, or in the 1 year following their fictitious surgery date.

Covariates and potential confounders identified from adult and paediatric literature are included in their logistic regression models for all age groups.  These are age, sex, race, year of surgery, cancer, chronic pain, mood/personality disorders (for ages 6-<12 & 12-18), and paediatric complex chronic conditions classification system. The statistical methods and analysis are well described and appear appropriate, and the sample size exceeds minimum requirement for power analysis.

Findings:

  1. Incidence of POUS (prolonged opioid use after surgery) are 0.77%, 0.76%, 1% & 3.8% of surgical patients ages 0-< 2, 2-<6, 6-<12 and 12-18 respectively.
  2. Type of surgery associated with increased rates of POUS by age groups:
  3. Ages 0-<2: myringotomy
  4. Ages 2-<6: adenoidectomy, tonsillectomy, adenotonsillectomy
  • Ages 6-<12: tonsillectomy, adenotonsillectomy, tympanoplasty with tympanomeatal flap, laparoscopic appendicectomy
  1. Ages 12-18: tonsillectomy, adenotonsillectomy, closed treatment of nose fracture, septoplasty, laparoscopic appendicectomy, removal of deep fixation device, arthroscopic knee chondroplasty, arthroscopic knee partial synovectomy, arthroscopic shoulder capsulorrhaphy.
  2. For ages 12-18, removal of completely impacted tooth negatively associated with POUS
  3. For ages 12-18:
  4. increasing age, history of mood/personality disorder, and history of chronic pain is positively associated with POUS
  5. male gender and Asian race are negatively associated with POUS
  6. For ages 2-18, a more recent year of surgery was negatively associated with POUS, probably reflecting increased awareness of opioid risks and overall decline in opioid prescription from 2013-2018 as reported by American Medical Association 2019 Opioid Task Force
  7. For PPOU (persistent post-operative opioid use)
  8. For ages 0-<12, PPOU occurred in fewer than 10 of the 105,449 (<0.009%) surgical patients with PPOU, and 11 of the 883,200 (0.001%) nonsurgical patients
  9. For ages 12-18, PPOU occurred in 37 (0.053%) surgical patients, and 107 (0.023%) nonsurgical patients
  • PPOU numbers were too low to build adjusted regression models across all 4 age groups

 

Comments:

This is a lengthy paper describing well a study with a large sample size that adds insight into incidence and some factors contributing to prolonged opioid use in paediatric surgical patients, which thankfully, is a rare outcome (approximately 1% overall).

Several limitations in the study that are discussed by the authors included:

  1. prescription fills at pharmacy do not necessarily reflect consumption by patients
  2. study population are patients with private insurance thus may not be generalizable to all paediatric populations
  3. there may be other unknown or unmeasured confounders

 

The authors also stated that use of multimodal analgesia and patient education can reduce postoperative pain and need for opioids, but went on to state that this is not translatable to reduction of POUS and PPOU, based on a 2017 paper1. This statement is somewhat misleading, as the study does not specifically look at types of multimodal analgesia used, use of regional anaesthesia in settings other than knee arthroscopy, management of perioperative patient and parental/carers anxiety, multi-disciplinary team input such as a dedicated theatre pharmacist, physiotherapy, occupational therapy and play therapy, and other complementary therapies such as hypnosis and cognitive behavioural therapy.

Additionally, confounding factors such as degree of social deprivation, parental/carer opioid use/misuse including usage of their child’s prescribed opioid, presence of opioid in breast milk especially in breastfeeding mothers on chronic opioids, cultural context such as regional variability of prescriber behaviour and accepted social norms, may also significantly affect the outcome of this study.

Take home message:

As anaesthetists, we are gatekeepers to surgical patients’ access to opioids.  We need to be consciously aware of the potential for POUS and PPOU, and individualise our postoperative pain management for each patient we look after, including optimising use of allied and support services in our workplace.  We can take an active role to help educate our medical and surgical colleagues, juniors and the public.

 

  1. Sun EC, Bateman BT, Memtsoudis SG, Neuman MD, Mariano ER, Baker LC. Lack of Association Between the Use of Nerve Blockade and the Risk of Postoperative Chronic Opioid Use Among Patients Undergoing Total Knee Arthroplasty: Evidence From the Marketscan Database. Anesth Analg. 2017;125(3):999-1007.

 

Reviewed by Dr K.C. Law

Journal Watch Search