Inappropriate labelling of patients as opioid allergic

Opioid prescribing, pain, and hospital stay of general surgery patients with oxycodone allergies in South Australia

BACKGROUND

The frequency of oxycodone adverse reactions, subsequent opioid prescription, effect on pain and patient care in general surgery patients are not well known. This study aimed to determine prevalence of documented oxycodone allergy and intolerances (independent variables) in a general surgical cohort, and association with prescribing other analgesics (particularly opioids), subjective pain scores, and length of hospital stay (dependent variables).

METHODS

This retrospective cohort study included general surgery patients from two South Australian hospitals between April 2020 and March 2022. Multivariable logistic regression evaluated associations between previous oxycodone allergies and intolerances, prescription records, subjective pain scores, and length of hospital stay.

RESULTS

Of 12 846 patients, 216 (1.7%) had oxycodone allergies, and 84 (0.7%) oxycodone intolerances. The 216 oxycodone allergy patients had lower odds of receiving oxycodone (OR 0.17, P < 0.001), higher odds of tramadol (OR 3.01, P < 0.001) and tapentadol (OR 2.87, P = 0.001), but 91 (42.3%) still received oxycodone and 19 (8.8%) morphine. The 84 with oxycodone intolerance patients had lower odds of receiving oxycodone (OR 0.23, P < 0.001), higher odds of fentanyl (OR 3.6, P < 0.001) and tramadol (OR 3.35, P < 0.001), but 42 (50%) still received oxycodone. Patients with oxycodone allergies and intolerances had higher odds of elevated subjective pain (OR 1.60, P = 0.013; OR 2.36, P = 0.002, respectively) and longer length of stay (OR 1.36, P = 0.038; OR 2.24, P = 0.002, respectively) than patients without these.

CONCLUSIONS

General surgery patients with oxycodone allergies and intolerances are at greater risk of worse postoperative pain and longer length of stay, compared to patients without. Many still receive oxycodone, and other opioids that could cause cross-reactivity.

Sex differences in type and occurrence of adverse reactions to opioid analgesics: a retrospective cohort study

OBJECTIVES

Sex as a biological variable affects response to opioids. However, few reports describe the prevalence of specific adverse reactions to commonly prescribed opioids in men and women separately. A large cohort was used to investigate sex differences in type and occurrence of adverse reactions associated with use of codeine, tramadol, oxycodone and hydrocodone.

DESIGN

Retrospective cohort study.

SETTING

Participants in the Right Drug, Right Dose, Right Time (RIGHT) Study.

PARTICIPANTS

The medical records of 8457 participants in the RIGHT Study who received an opioid prescription between 1 January 2004 and 31 December 2017 were reviewed 61% women, 94% white, median age (Q1-Q3)=58 (47-66).

PRIMARY AND SECONDARY OUTCOME MEASURES

Adverse reactions including gastrointestinal, skin, psychiatric and nervous system issues were collected from the allergy section of each patient's medical record. Sex differences in the risk of adverse reactions due to prescribed opioids were modelled using logistic regression adjusted for age, body mass index, race and ethnicity.

RESULTS

From 8457 participants (of which 449 (5.3%) reported adverse reactions), more women (6.5%) than men (3.4%) reported adverse reactions to at least one opioid (OR (95% CI)=2.3 (1.8 to 2.8), p<0.001). Women were more likely to report adverse reactions to tramadol (OR (95% CI)=2.8 (1.8 to 4.4), p<0.001) and oxycodone (OR (95% CI)=2.2 (1.7 to 2.9), p<0.001). Women were more likely to report gastrointestinal (OR (95% CI)=3.1 (2.3 to 4.3), p<0.001), skin (OR (95% CI)=2.1 (1.4 to 3.3), p=0.001) and nervous system issues (OR (95% CI)=2.3 (1.3 to 4.2), p=0.004).

CONCLUSIONS

These findings support the importance of sex as a biological variable to be factored into pain management studies.

Dexmedetomidine Use in a Case of Severe Cancer Pain

A 58-year-old male with chronic pancreatitis was seen by the palliative care service for pain and agitation related to a recent diagnosis of disseminated abdominal cancer. Increasing symptom burden, including pain and nausea, in the face of escalating doses of multiple opioid and sedative medications resulted in the addition of dexmedetomidine to successfully control his symptoms. Visceral sensitization related to his chronic pancreatitis likely increased his pain perception and required a multimodal approach to control his symptoms.

History of opioid allergy: what significance?

Objective. To assess how health professionals would manage a patient’s pain when the patient is labelled as allergic to opioid analgesics.

Methods. A clinical case scenario, describing a patient obviously requiring opioid pain management but reporting a morphine allergy, was designed and pretested. This was distributed to medical (students, interns/residents, registrars, consultants) and nursing staff of Toowoomba Health Service District. All staff had some experience in pain management, though this varied widely. Respondents were asked to review the history and briefly comment on how the patient’s pain should be managed.

Results. Overall response rate was 46%. Doctors returned 47% (39/83) of scenarios, with 53% requesting further information on the nature of the allergy before using opioids. Nurses response rate was 45.2% (42/93), with only 21.4% requesting more information. Eighty three per cent (15/18) of doctors and 60% (20/33) of nurses, who didn’t query the nature of the morphine allergy, recommended opioid medication. No one specifically suggested using structurally dissimilar opioids to morphine if an allergy really existed.

Conclusion. Many health care staff either missed or ignored the allergy or assumed it was really an adverse effect and not significant, potentially placing the patient at risk of serious consequences, including anaphylaxis. Despite the low incidence of true opioid allergy, health professionals must fully investigate purported allergies to determine their validity. Patients should never be administered medications until their likelihood of experiencing a true allergy is determined.

Nuclear medicine tests for acute gastrointestinal conditions

Acute cholecystitis (AC) and lower-gastrointestinal (GI) bleeding are 2 emergencies commonly encountered in nuclear medicine. Evidence of AC on hepatobiliary scintigraphy (HBS) allows for confident diagnosis and provides support for definitive surgical treatment. Proper patient preparation is essential for HBS including fasting and the use of pharmacologic adjuncts is sometimes required. Pharmacologic adjuncts may also be administered during HBS to shorten the length of the examination and increase its specificity. In the interpretation of HBS, there are several sources of false-positive results to be aware of, most commonly chronic cholecystitis. False-negative results on HBS are usually the result of mistaking another structure, such as a dilated cystic duct, for the gallbladder. Abdominal ultrasound is the appropriate initial test in patients with suspected AC, but HBS is an excellent second tier test for the diagnosis of AC in the work-up of indeterminate cases by sonography. GI bleeding scintigraphy plays an important role in the evaluation and management of patients with acute lower-GI bleeding. Scintigraphy serves to localize sites of active GI bleeding and stratify those patients who would benefit from aggressive treatment (surgery or arteriography) vs those who can be managed medically. Pretest involvement of respective services is critical for successful bleeding site confirmation and therapy by interventional radiology or surgery or both. Single photon emission computed tomography/computed tomography erythrocyte scintigraphy has demonstrated superior accuracy and precision over planar scintigraphy in the diagnosis of acute GI bleeding. Additionally, single photon emission computed tomography/computed tomography scintigraphy of GI bleeding provides useful supplemental anatomical information that benefits patient management.

Hepatobiliary scintigraphy in acute cholecystitis

Hepatobiliary scintigraphy is a mature imaging technique for evaluation of patients with acute cholecystitis (AC). It is effective in calculous and acalculous forms of AC. The test is used in contemporary medical practice as the arbiter when the findings from screening abdominal ultrasound do not fit a clinical picture. It is also performed in severely ill patients who have AC suspected on other testing, but whose frail condition and high operative risk demand the highest level of certainty. This review, therefore, examines all technique variations of hepatobiliary scintigraphy, offering an approach that may best fit a variety of clinical situations and philosophies on AC.

Histamine-releasing and allergenic properties of opioid analgesic drugs: resolving the two

Opioid analgesics are amongst the most commonly administered drugs in hospitals. Whether natural or synthetic, they show some common structural features, morphine-like pharmacological action and binding specificity for complementary opioid receptors. Tramadol differs from the other opioid analgesics in possessing monoaminergic activity in addition to its affinity for the µ opioid receptor. Many opioids are potent histamine releasers producing a variety of haemodynamic changes and anaphylactoid reactions, but the relationship of the appearance of these effects to the histamine plasma concentration is complex and there is no direct and invariable relationship between the two. Studies of the histamine-releasing effects, chiefly centred on morphine, reveal variable findings and conclusions often due to a range of factors including differences in technical measurements, dose, mode of administration, site of injection, the anatomical distribution of histamine receptors and heterogeneity of patient responses. Morphine itself has multiple direct effects on the vasculature and other haemodynamically-active mediators released along with histamine contribute to the variable responses to opioid drug administration. Despite their heavy use and occasional apparent anaphylactic-like side-effects, immunoglobulin E antibody-mediated immediate hypersensitivity reactions to the drugs are not often encountered. Uncertainties associated with skin testing with these known histamine-releasers, and the general unavailability of opioid drug-specific immunoglobulin E antibody tests contribute to the frequent failure to adequately investigate and establish underlying mechanisms of reactions by distinguishing anaphylactoid from true anaphylactic reactions. Clinical implications for diagnosis of reactions and some speculations on the rarity of true Type 1 allergies to these drugs are presented.

Intravenous Opioids for Severe Acute Pain in the Emergency Department

Objective:

To review clinical trials of intravenous opioids for severe acute pain in the emergency department (ED) and to provide an approach for optimization of therapy.

Data Sources:

Articles were identified through a search of Ovid/MEDLINE (1948-August 2010), PubMed (1950-August 2010), Cochrane Central Register of Controlled Trials (1991-August 2010), and Google Scholar (1900-August 2010). The search terms used were pain, opioid, and emergency department.

Study Selection and Data Extraction:

The search was limited by age group to adults and by publication type to comparative studies. Studies comparing routes of administration other than intravenous or using non-opioid comparators were not included. Bibliographies of all retrieved articles were reviewed to obtain additional articles. The focus of the search was to identify original research that compared intravenous opioids used for treatment of severe acute pain for adults in the ED.

Data Synthesis:

At equipotent doses, randomized controlled trials have not shown clinically significant differences in analgesic response or adverse effects between opioids studied. Single opioid doses less than 0.1 mg/kg of intravenous morphine, 0.015 mg/kg of intravenous hydromorphone, or 1 μg/kg of intravenous fentanyl are likely to be inadequate for severe, acute pain and the need for additional doses should be anticipated. In none of the randomized controlled trials did patients develop respiratory depression requiring the use of naloxone. Future trials could investigate the safety and efficacy of higher doses of opioids. Implementation of nurse-initiated and patient-driven pain management protocols for opioids in the ED has shown improvements in timely provision of appropriate analgesics and has resulted in better pain reduction.

Conclusions:

Currently, intravenous administration of opioids for severe acute pain in the ED appears to be inadequate. Opioid doses in the ED should be high enough to provide adequate analgesia without additional risk to the patient. EDs could implement institution-specific protocols to standardize the management of pain.

Structured product labeling improves detection of drug-intolerance issues

OBJECTIVES

This study sought to assess the value of the Health Level 7/U.S. Food and Drug Administration Structured Product Labeling (SPL) drug knowledge representation standard and its associated terminology sources for drug-intolerance (allergy) decision support in computerized provider order entry (CPOE) systems.

DESIGN

The Regenstrief Institute CPOE drug-intolerance issue detection system and its knowledge base was compared with a method based on existing SPL label content enriched with knowledge sources used with SPL (NDF-RT/MeSH). Both methods were applied to a large set of drug-intolerance (allergy) records, drug orders, and medication dispensing records covering >50,000 patients over 30 years.

MEASUREMENTS

The number of drug-intolerance issues detected by both methods was counted, as well as the number of patients with issues, number of distinct drugs, and number of distinct intolerances. The difference between drug-intolerance issues detected or missed by either method was qualitatively analyzed.

RESULTS

Although <70% of terms were mapped to SPL, the new approach detected four times as many drug-intolerance issues on twice as many patients.

CONCLUSION

The SPL-based approach is more sensitive and suggests that mapping local dictionaries to SPL, and enhancing the depth and breadth of coverage of SPL content are worth accelerating. The study also highlights specificity problems known to trouble drug-intolerance decision support and suggests how terminology and methods of recording drug intolerances could be improved.