Association between access block and time to parenteral opioid analgesia in renal colic: a pilot study

Emerg Med Australas. 2009 Feb;21(1):38-42. doi: 10.1111/j.1742-6723.2008.01146.x.


Objective: To seek an association between access block and time to parenteral opioid analgesia (POA) in ED patients presenting with renal colic.

Methods: Renal colic patients given POA were retrospectively identified over 3 months. Time of administration of POA was abstracted from patients' charts. Access block data, time of arrival and demographics were retrieved electronically. A logistic regression was used to seek an association between time to POA (dichotomized into <1 h and >1 h of arrival) with daily access block (proportion of patients requiring hospital admission in a 24 h period who have a total ED time >8 h, dichotomized at its median), time of administration of POA (00.00-07.59 hours [T1], 08.00-15.59 hours [T2], 16.00-23.59 hours [T3] ), age and sex.

Results: Of 69 patients, 42 (60.1%, 95% CI 51-70%) received POA within 1 h. Access block occurred daily (median 28.8%, range 6.8-53.1%). Mean hourly ED attendance rates for all patients during T1, T2 and T3 were 4.0, 11.7 and 7.8 patients/h respectively. As predictors of time to POA (>1 h vs<or=1 h), the adjusted OR for access block (>or=29% vs <29%) was 1.0 (95% CI 0.4-2.9), T3 versus T2 was 5.0 (95% CI 1.4-17.7), T1 versus T2 was 1.0 (95% CI 0.3-23.8), age (>or=47 years vs <47 years) was 0.8 (95% CI 0.3-2.3) and for sex (female vs male) was 0.4 (95% CI 0.1-1.6).

Conclusion: Time to POA was related to time of administration, but not to access block. Access block might be too crude a measure to quantify ED overcrowding, and so its influence on time to POA may not be exhibited.

MeSH terms

  • Adult
  • Analgesia / instrumentation
  • Analgesia / methods*
  • Analgesics, Opioid / administration & dosage*
  • Colic / drug therapy*
  • Drug Administration Schedule
  • Female
  • Health Services Accessibility / statistics & numerical data*
  • Humans
  • Infusions, Parenteral
  • Kidney Diseases / drug therapy*
  • Male
  • Middle Aged
  • Pilot Projects
  • Quality Assurance, Health Care / methods*
  • Queensland
  • Retrospective Studies


  • Analgesics, Opioid