Exploration of Overdose Risk Score and Postoperative Complications and Health Care Use After Total Knee Arthroplasty

IMPORTANCE

The adverse outcomes after total knee arthroplasty (TKA) associated with preoperative prescription drug use (ie, use of narcotics, sedatives, and stimulants) have been established but are not well quantified.

OBJECTIVE

To test the association of preoperative overdose risk score (ORS) with postoperative health care use.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study was conducted using data on a consecutive sample of individuals who underwent primary TKA from November 2018 through March 2020 at a tertiary care health system. Data were collected using the Orthopaedic Minimal Data Set Episode of Care, a validated data-collection system for all elective orthopedic surgical interventions taking place within the health care system. Outcomes were assessed at 90 days postoperatively. Individuals whose preoperative baseline characteristics or ORS were not provided or who declined to participate were excluded. Data were analyzed from September through October 2020.

EXPOSURE

Patient-specific preoperative ORS, as measured using NarxCare, associated with patterns of prescription drug use.

MAIN OUTCOMES AND MEASURES

Associations between patient-specific ORS categories and 90-day postoperative health care use (ie, prolonged hospital length of stay [LOS; ie, >2 days], nonhome discharge, all-cause 90-day readmission, emergency department [ED] visits, and reoperation) were evaluated. Outcomes were also compared between a group of individuals with ORS less than 300 vs those with ORS 300 or greater who were propensity score matched (4:1; caliper, 0.1) using demographic characteristics (ie, age, sex, race, body mass index, and smoking status) and baseline comorbidities.

RESULTS

Among 4326 individuals who underwent primary TKA, 2623 (60.63%) were women, 3602 individuals (83.26%) were White, the mean (SD) BMI was 32.8 (6.9), and the mean (SD) age was 66.6 (9.2) years; 90-day follow-up was available for the entire cohort. The predominant preoperative diagnosis was osteoarthritis, occurring among 4170 individuals (96.4%). For individuals with an ORS of 300 to 399, there were significantly higher odds of a prolonged LOS (odds ratio [OR], 2.03; 95% CI, 1.46-2.82; P < .001), nonhome discharge (OR, 2.01; 95% CI, 1.37-2.94; P < .001), all-cause 90-day readmission (OR, 1.56; 95% CI, 1.01-2.42; P < .001), and ED visits (OR, 1.62; 95% CI, 1.11-2.38; P = .01) compared with individuals who were prescription drug naive (ie, ORS = 0). Individuals in the highest ORS category (ie, ORS ≥ 500) had the highest ORs for prolonged LOS (OR, 3.71; 95% CI, 2.00-6.87; P < .001), nonhome discharge (OR, 4.09; 95% CI, 2.02-8.29; P < .001), 90-day readmission (OR, 4.41; 95% CI, 2.23-8.71; P < .001), and 90-day reoperation (OR, 6.09; 95% CI, 1.44-25.80; P = .01). Propensity score matching confirmed the association between an ORS of 300 or greater and the incidence of prolonged LOS (244 individuals [11.6%] vs 130 individuals [23.0%]; P < .001), nonhome discharge (176 individuals [8.4%] vs 93 individuals [16.4%]; P < .001), all-cause 90-day readmission (119 individuals [5.7%] vs 65 individuals [11.5%]; P < .001), and all-cause ED visits (198 individuals [9.4%] vs 76 individuals [13.4%]; P = .006).

CONCLUSIONS AND RELEVANCE

This study found that higher ORS was associated with increased health care use after primary TKA. These findings suggest that an ORS of 300 or greater could be used to designate increased risk and guide the preoperative surgeon-patient discussion to modify prescription drug use patterns.

Identifying and classifying opioid-related overdoses: A validation study

PURPOSE

The study aims to develop and validate algorithms to identify and classify opioid overdoses using claims and other coded data, and clinical text extracted from electronic health records using natural language processing (NLP).

METHODS

Primary data were derived from Kaiser Permanente Northwest (2008-2014), an integrated health care system (~n > 475 000 unique individuals per year). Data included International Classification of Diseases, Ninth Revision (ICD-9) codes for nonfatal diagnoses, International Classification of Diseases, Tenth Revision (ICD-10) codes for fatal events, clinical notes, and prescription medication records. We assessed sensitivity, specificity, positive predictive value, and negative predictive value for algorithms relative to medical chart review and conducted assessments of algorithm portability in Kaiser Permanente Washington, Tennessee State Medicaid, and Optum.

RESULTS

Code-based algorithm performance was excellent for opioid-related overdoses (sensitivity = 97.2%, specificity = 84.6%) and classification of heroin-involved overdoses (sensitivity = 91.8%, specificity = 99.0%). Performance was acceptable for code-based suicide/suicide attempt classifications (sensitivity = 70.7%, specificity = 90.5%); sensitivity improved with NLP (sensitivity = 78.7%, specificity = 91.0%). Performance was acceptable for the code-based substance abuse-involved classification (sensitivity = 75.3%, specificity = 79.5%); sensitivity improved with the NLP-enhanced algorithm (sensitivity = 80.5%, specificity = 76.3%). The opioid-related overdose algorithm performed well across portability assessment sites, with sensitivity greater than 96% and specificity greater than 84%. Cross-site sensitivity for heroin-involved overdose was greater than 87%, specificity greater than or equal to 99%.

CONCLUSIONS

Code-based algorithms developed to detect opioid-related overdoses and classify them according to heroin involvement perform well. Algorithms for classifying suicides/attempts and abuse-related opioid overdoses perform adequately for use for research, particularly given the complexity of classifying such overdoses. The NLP-enhanced algorithms for suicides/suicide attempts and abuse-related overdoses perform significantly better than code-based algorithms and are appropriate for use in settings that have data and capacity to use NLP.

Performance of the Centers for Medicare & Medicaid Services' Opioid Overutilization Criteria for Classifying Opioid Use Disorder or Overdose

This study characterizes the accuracy of CMS’ Overutilization Monitoring System for correctly identifying prescription opioid users at risk of opioid use disorder (OUD) or overdose between 2011 and 2014.

State Unintentional Drug Overdose Reporting Surveillance: Opioid Overdose Deaths and Characteristics in Rhode Island

Unintentional opioid overdoses are a growing public health epidemic in the United States. Rhode Island is also faced with a challenging crisis of drug overdose deaths. The State Unintentional Drug Overdose Reporting Surveillance (SUDORS) data from the second half of 2016 were used to present opioid overdose deaths and characteristics in Rhode Island. During July-December 2016, 142 individuals died of opioid overdose in Rhode Island. People who died by opioid overdose were more likely to be 25-65 years old, male, and non-Hispanic white. The most common precipitating circumstances were substance abuse (88%), current mental health problems (43%), and physical health problems (27.5%). Over 83% of decedents had 2 or more substances attribute to causing their death, with fentanyl (71.1%) as the most common substance. Only 36.6% of decedents had naloxone administered. Fatal opioid overdose data are important for understanding this public health crisis and can guide overdose intervention efforts.

Misuse of the Naranjo Adverse Drug Reaction Probability Scale in toxicology

CONTEXT

When an adverse event occurs in an overdose patient, it may be difficult to determine whether the event was caused by the ingested drug or by medical therapy. Naranjo et al. developed a probability scale, the Naranjo Adverse Drug Reaction Probability Scale (Naranjo Scale), to assess the probability that a drug administered in therapeutic doses caused an adverse event thereby classifying the event as an adverse drug reaction (ADR). Although Naranjo et al. specifically excluded the application of this scale to adverse events in overdose patients, case reports demonstrate that authors continue to apply the Naranjo Scale to events in these patients.

OBJECTIVE

The World Health Organization defines an ADR as occurring only when drugs are administered in therapeutic doses. Yet ADRs continue to be reported in overdose patients. We sought to examine the use of the Naranjo scale in case reports of overdose patients to assess the potential consequences of that application.

METHODS

A Medline search via PubMed without language limits, through September 2012, using the search terms "Naranjo" and "overdose" or "poisoning" yielded 146 publications. Additional searches were performed to find articles with keywords of the Naranjo Scale development, current applications and validity of application in specific populations such as critically ill and overdose patients.

RESULTS

From the 146 publications, we identified 17 case reports or case series of overdose patients in which the Naranjo Scale was applied to a clinical complication to support a causal relationship between an administered drug and the clinical complication and thereby classify the clinical complication as an ADR. We also identified a recent publication in which the Naranjo Scale was applied to a new treatment modality (lipid emulsion) that is currently administered to overdose patients. Original publication of the Naranjo Scale and studies evaluating its use in critically ill patients or those with drug-induced disease were also retrieved.

CONCLUSION

Adverse events that occur in overdose patients are excluded from the definition of ADR. Yet in case reports or series of overdose patients, the Naranjo Scale has been applied to assess the probability an event was caused by the ingested drug or therapeutic modality. This application of the Naranjo Scale is not scientifically valid and may lead to erroneous conclusions. There is no evidence to support the application of the Naranjo scale to any events that occur in overdose patients.

[Dosis sola facit venenum: outcome of intoxications in a Swiss university hospital]

Poisoning is a frequent disease in an emergency division. During four years we observed patients with poisoning related to there reason of intoxication, the degree of severity, age group and sex, and tried to make conclusions about lethal outcome on behalf of our data. The severity was defined by the «poison severity scale» (PSS). 1515 patients with intoxication in four years were documented. 152 (10%) of them had a severe intoxication or lethal outcome. In women suicide predominated as reason of severe intoxication, whereas in men an abuse of alcool and drugs was mostly seen. A multidisciplinary approach is important for handling intoxicated patients. Our investigation showed a good somatical outcome of patients with severe intoxication. Mortality was 5% (7/152 patients).

TESS-based dose–response using pediatric clonidine exposures

OBJECTIVE

The toxic and lethal doses of clonidine in children are unclear. This study was designed to determine whether data from the American Association of Poison Control Centers Toxic Exposure Surveillance System (TESS) could be utilized to determine a dose-response relationship for pediatric clonidine exposure.

METHODS

3,458 single-substance clonidine exposures in children <6 years of age reported to TESS from January 2000 through December 2003 were examined. Dose ingested, age, and medical outcome were available for 1550 cases. Respiratory arrest cases (n = 8) were classified as the most severe of the medical outcome categories (Arrest, Major, Moderate, Mild, and No effect). Exposures reported as a "taste or lick" (n = 51) were included as a dose of 1/10 of the dosage form involved. Dose ranged from 0.4 to 1980 (median 13) microg/kg. Weight was imputed based on a quadratic estimate of weight for age. Dose certainty was coded as exact (26% of cases) or not exact (74%). Medical outcome (response) was examined via logistic regression using SAS JMP (release 5.1).

RESULTS

The logistic model describing medical outcome (P < 0.0001) included Log dose/kg (P = 0.0000) and Certainty (P = 0.045).

CONCLUSION

TESS data can provide the basis for a statistically sound description of dose-response for pediatric clonidine poisoning exposures.

Predictors of accidental fatal drug overdose among a cohort of injection drug users

OBJECTIVES

This study evaluated factors associated with accidental fatal drug overdose among a cohort of injection drug users (IDUs).

METHODS

In a prospective cohort study of 2849 IDUs in King County, Washington, deaths were identified by electronically merging subject identifiers with death certificate records. Univariate and multivariate Cox regression analyses were performed to identify predictors of overdose mortality.

RESULTS

Thirty-two overdoses were observed. Independent predictors of overdose mortality were bisexual sexual orientation (relative risk [RR] = 4.86; 95% confidence interval [CI] = 2.30, 13.2), homelessness (RR = 2.30; 95% CI = 1.06, 5.01), infrequent injection of speedballs (RR = 5.36; 95% CI = 1.58, 18.1), daily use of powdered cocaine (RR = 4.84; 95% CI = 1.13, 20.8), and daily use of poppers (RR = 22.0; 95% CI = 1.74, 278).

CONCLUSIONS

Sexual orientation, homelessness, and drug use identify IDUs who may benefit from targeted interventions.

Lithium poisoning from a poison control center perspective

The purpose of this study was to evaluate the severity of lithium poisoning from a poison control center-based population and the correlation of the Hansen and Amdisen classification with outcome and lithium levels in that setting. All lithium overdoses brought to the attention of the poison control center were prospectively observed during 1 year. Demographic data, amount ingested, coingestants, symptoms and signs, lithium levels, treatment, and outcome were recorded. There were 12 acute lithium overdoses: 5, 5, and 2 with grade 0, 1, and 2, respectively. No patients required hemodialysis or had sequelae or died. There were 174 acute-on-chronic overdoses: 66, 85, 15, and 8 with grade 0, 1, 2, and 3, respectively. Six patients underwent hemodialysis; none had sequelae but one died. There were 19 chronic poisonings: 9, 9, and 1 with grade 1, 2, and 3, respectively. Three patients underwent hemodialysis; one had sequelae and one died. Patients classified as grade 2 had higher lithium levels than those with grade 1 in patients with only lithium poisoning (3.08 +/- 0.77 vs. 2.09 +/- 0.91 mmol/L P = 0.03). The study concluded that morbidity (0.5%) and mortality (1%) associated with lithium poisoning are rarely observed. The Hansen and Amdisen classification does not appear to be a useful clinical tool to predict either morbidity or mortality and does not correlate well with lithium levels.

Deadliness of declining drug abuse

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Intentional drug overdose: predictors of clinical course in the intensive care unit

OBJECTIVE

To examine the characteristics of patients admitted to the Medical Intensive Care Unit (MICU) after intentional drug overdose.

DESIGN

Retrospective chart review, descriptive.

SETTING

Midwestern teaching hospital.

SUBJECTS

Convenience sample of 43 patients admitted to the MICU after intentional drug overdose.

OUTCOME MEASURES

Survival and disposition of those patients who survived and were discharged from the MICU.

RESULTS

Ninety-five percent of the patients survived and were discharged from the MICU; Acute Physiology and Chronic Health Evaluation II scores ranged from 1 to 29 (mean, 8); Glascow Coma Scale scores ranged from 3 to 15 (mean 12.5); five patients were intubated and two patients had serious electrocardiograph changes requiring pharmacologic intervention for dysrhythmia.

CONCLUSIONS

Neurologic findings were the best indicators of serious complications after drug overdose. THerefore, patients with a Glascow Coma Scale score of more than six, and who are not intubated, may not need admission to an intensive care unit.

Prognostic score for kerosene oil poisoning

Ninety five consecutive children with kerosene oil poisoning were studied, the first 70 retrospectively (internal group) and the rest 25, prospectively (external group) over a period of 3 years and 8 months. Based on clinical features and severity of illness in initial 70 cases, a weighted scoring system to determine the outcome was evolved. This included: (i) fever--absent 0, present 1; (ii) severe malnutrition--absent 0, present 1; (iii) respiratory distress--absent 0, present 2, with cyanosis 4; and (iv) neurological symptoms--absent 0, present 2, with convulsions 4. The scores ranged from 0 to 10 in the internal group. Using discriminate function analysis, a score of 4 or more was found to be associated with prolonged hospital stay and complications. The risk of dying increased if the score was equal to or more than 8. The predictive value of the score was 85.7%. For validation, this scoring was applied to the external group as well and 84% of cases could be correctly predicted.

Prompt recovery from severe cholinesterase-inhibitor poisoning--remarks on classification and therapy of organophosphate poisoning

In organophosphate intoxication the assessment of both the degree of severity of poisoning and the initial dose of pralidoxime and atropine are as yet based only on clinical symptoms. We present three patients with clinically severe organophosphate poisoning in whom a prompt recovery from central nervous symptoms occurred after the administration of low doses of atropine and pralidoxime. It is suggested that the true severity of organophosphate intoxication as well as the initial therapy should be determined by the amount ingested, the propensity for aging, and the pharmacodynamic properties of the organophosphorus compound, as well as by the time interval between exposure and initiation of appropriate treatment, as far as these data can be verified in the individual patient.

A critical study of the APACHE II scoring system using earlier data collection

The APACHE II severity of illness scoring system was prospectively studied on 756 patients admitted to a general intensive care unit (ICU) from January 1986 to June 1988. Admission data were used. Individual and group risk of death were calculated for 3 diagnostic categories commonly seen in the A&E department and requiring admission to an ICU. The APACHE II score on admission tended to underestimate the risk of death following operative and non-operative trauma, and self-poisoning. This may have been related to the use of an analysis not yet validated against values obtained on admission to ICU. Such validation is urgently needed on a UK population if APACHE II scoring is to be of value in the A&E department.

Evaluation of the validity of the Done nomogram in the management of acute salicylate intoxication

To evaluate the validity of the Done nomogram in the management of acute adult salicylate intoxications, a retrospective review of cases at our institution was performed. The degree of severity (ie, asymptomatic, mild, moderate, or severe) as determined by plotting the serum concentration and time on the nomogram for 55 acute salicylate intoxications was compared with the degree of severity decided on by three experienced emergency physicians who based their decision on the clinical presentation of the cases and the original criteria devised by Done for each category of severity. Discordant classifications between the nomogram and the physicians provided a basis on which a predictive index for the nomogram and various subsets of cases could be determined. The calculated predictive index for the nomogram was 0.42, with the highest predictive index of 0.79 in the mild salicylate category. The nomogram tends to overpredict the severity of intoxication in the moderate and severe categories. There was no significant difference between predictive indexes of mixed versus nonmixed or enteric-coated acetylsalicylic acid versus plain acetylsalicylic acid cases, although the nomogram had a higher predictive index when used for concentrations drawn six to 12 hours after ingestion (P less than .01, Fisher's exact test). Decisions on management of an acute salicylate overdose should be based on clinical presentation and good judgment as well as the serum salicylate concentration in relation to the time of ingestion.