Postsurgical Pain Risk Stratification to Enhance Pain Management Workflow in Adult Patients: Design, Implementation, and Pilot Evaluation.

BACKGROUND: Exposure to opioids after surgery is the initial contact for some people who develop chronic opioid use disorder. Hence, effective postoperative pain management, with less reliance on opioids, is critical. The Perioperative Opioid Quality Improvement (POQI) program developed (1) a digital health platform leveraging patient-survey-reported risk factors and (2) a postsurgical pain risk stratification algorithm to personalize perioperative care by integrating several commercially available digital health solutions into a combined platform. Development was reduced in scope by the COVID-19 pandemic. OBJECTIVE: This pilot study aims to assess the screening performance of the risk algorithm, quantify the use of the POQI platform, and evaluate clinicians' and patients' perceptions of its utility and benefit. METHODS: A POQI platform prototype was implemented in a quality improvement initiative at a Canadian tertiary care center and evaluated from January to September 2022. After surgical booking, a preliminary risk stratification algorithm was applied to health history questionnaire responses. The estimated risk guided the patient assignment to a care pathway based on low or high risk for persistent pain and opioid use. Demographic, procedural, and medication administration data were extracted retrospectively from the electronic medical record. Postoperative inpatient opioid use of >90 morphine milligram equivalents per day was the outcome used to assess algorithm performance. Data were summarized and compared between the low- and high-risk groups. POQI use was assessed by completed surveys on postoperative days 7, 14, 30, 60, 90, and 120. Semistructured patient and clinician interviews provided qualitative feedback on the platform. RESULTS: Overall, 276 eligible patients were admitted for colorectal procedures. The risk algorithm stratified 203 (73.6%) as the low-risk group and 73 (26.4%) as the high-risk group. Among the 214 (77.5%) patients with available data, high-risk patients were younger than low-risk patients (age: median 53, IQR 40-65 years, vs median 59, IQR 49-69 years, median difference five years, 95% CI 1-9; P=.02) and were more often female patients (45/73, 62% vs 80/203, 39.4%; odds ratio 2.5, 95% CI 1.4-4.5; P=.002). The risk stratification was reasonably specific (true negative rate=144/200, 72%) but not sensitive (true positive rate=10/31, 32%). Only 39.7% (85/214) patients completed any postoperative quality of recovery questionnaires (only 14, 6.5% patients beyond 60 days after surgery), and 22.9% (49/214) completed a postdischarge medication survey. Interviewed participants welcomed the initiative but noted usability issues and poor platform education. CONCLUSIONS: An initial POQI platform prototype was deployed operationally; the risk algorithm had reasonable specificity but poor sensitivity. There was a significant loss to follow-up in postdischarge survey completion. Clinicians and patients appreciated the potential impact of preemptively addressing opioid exposure but expressed shortcomings in the platform's design and implementation. Iterative platform redesign with additional features and reevaluation are required before broader implementation.

Association of chronic poststernotomy pain and health-related quality of life: a prospective cohort study.

PURPOSE: Chronic poststernotomy pain (CPSP) after cardiac surgery is multifactorial and impacts patient recovery. We aimed to evaluate the association between CPSP severity and health-related quality of life at six months after cardiac surgery. METHODS: This was a single-centre prospective cohort study of patients who underwent cardiac surgery with median sternotomy between September 2020 and March 2021. Telephone interviews were conducted at six and 12 months postoperatively using the Short Form McGill Pain Questionnaire and the EQ-5D-5L. Strength of correlation was described using Spearman's correlation coefficient. Multivariable regression analysis was used to account for confounding variables. RESULTS: A total of 252 patients responded to the six-month interview (response rate, 65%). The mean (standard deviation) age of respondents was 65 (13) yr. Twenty-nine percent of respondents (72/252) reported CPSP at six months, and 14% (41/252) reported more than mild pain (score ≥ 2/5). At 12 months, of the 89% (64/72) patients who responded, 47% (30/64) still reported pain. The strength of the correlation between pain scores and EQ-5D-5L was weak (Spearman's correlation coefficient, -0.3). Risk factors for CPSP at six months included higher pain score on postoperative day 1, history of chronic pain prior to surgery, and history of depression. Intraoperative infusion of dexmedetomidine or ketamine was associated with a reduced risk of CPSP at six months. CONCLUSION: Chronic poststernotomy pain still affects patient recovery at six and 12 months after cardiac surgery. The severity of that pain is poorly correlated with patients' quality of life. STUDY REGISTRATION: www.osf.io ( https://osf.io/52rsw ); registered 14 May 2022.

RéSUMé: OBJECTIF: La douleur chronique post-sternotomie (DCPS) après une chirurgie cardiaque est multifactorielle et a un impact sur le rétablissement des patient·es. Nous avons cherché à évaluer l'association entre la sévérité de la DCPS et la qualité de vie liée à la santé six mois après la chirurgie cardiaque. MéTHODE: Il s'agissait d'une étude de cohorte prospective monocentrique portant sur des patient·es ayant bénéficié d'une chirurgie cardiaque avec sternotomie médiane entre septembre 2020 et mars 2021. Des entrevues téléphoniques ont été menées à six et 12 mois après l'opération en se servant du questionnaire abrégé de McGill sur la douleur et de l'EQ-5D-5L. La force de corrélation a été décrite à l'aide du coefficient de corrélation de Spearman. Une analyse de régression multivariée a été utilisée pour tenir compte des variables confondantes. RéSULTATS: Au total, 252 patient·es ont répondu à l'entrevue à six mois (taux de réponse de 65 %). L'âge moyen (écart type) des répondant·es était de 65 (13) ans. Vingt-neuf pour cent des personnes répondantes (72/252) ont déclaré avoir été atteintes de DCPS à six mois, et 14 % (41/252) ont signalé une douleur plus que légère (score ≥ 2/5). À 12 mois, sur les 89 % (64/72) personnes ayant répondu, 47 % (30/64) signalaient encore de la douleur. La force de la corrélation entre les scores de douleur et l'EQ-5D-5L était faible (coefficient de corrélation de Spearman, −0,3). Les facteurs de risque de DCPS à six mois comprenaient un score de douleur plus élevé au jour 1 postopératoire, des antécédents de douleur chronique avant la chirurgie et des antécédents de dépression. Une perfusion peropératoire de dexmédétomidine ou de kétamine a été associée à une réduction du risque de DCPS à six mois. CONCLUSION: La douleur chronique post-sternotomie affecte toujours le rétablissement des patient·es six et 12 mois après la chirurgie cardiaque. La sévérité de cette douleur est faiblement corrélée à la qualité de vie des patient·es. ENREGISTREMENT DE L'éTUDE: www.osf.io ( https://osf.io/52rsw ); enregistrée le 14 mai 2022.

Overlaps in pharmacology for the treatment of chronic pain and mental health disorders.

There is significant overlap in the pharmacological management of pain and psychological disorders. Appropriate treatment of patients' comorbid psychological disorders, including sleep disturbances often leads to an improvement in reported pain intensity. The three first line agents for neuropathic pain include tricyclic antidepressants and serotonin norepinephrine reuptake inhibitors which are medications originally developed as antidepressants. The other first line medication for chronic neuropathic pain are anticonvulsant medications initially brought to the market-place for the treatment of epilepsy and are also now being used for the treatment of anxiety disorders and substance withdrawal symptoms. The efficacy of opioids for chronic pain is contentious, but it is agreed that the patients at highest risk for opioid misuse and addiction are patients with underlying psychological disorders who use opioids for their euphoric effects. Similarly, benzodiazepines may present a problem in patients with chronic pain, as up to one third of patients with pain are concomitantly prescribed benzodiazepines, and when combined with other sedating analgesic medications they put patients at increased risk for adverse events and polysubstance misuse. Finally, there is growing evidence for the efficacy of cannabis for treating neuropathic pain, but the consumption of cannabis has been associated with increased risk of psychosis in adolescents, and may be associated with an increased risk for developing bipolar disorder and anxiety disorders. The use of cannabis is associated with an increased risk of substance misuse in both adolescents and adults. In this narrative review, we examine the evidence for the use of several medications used for the treatment of both pain and psychological disorders, and their proposed mechanisms of action, in addition to special concerns for patients with comorbid pain and psychological disorders.

Psychological treatments for the management of postsurgical pain: a systematic review of randomized controlled trials.

BACKGROUND: Inadequately managed pain is a risk factor for chronic postsurgical pain (CPSP), a growing public health challenge. Multidisciplinary pain-management programs with psychological approaches, including cognitive behavioral therapy (CBT), acceptance and commitment therapy (ACT), and mindfulness-based psychotherapy, have shown efficacy as treatments for chronic pain, and show promise as timely interventions in the pre/perioperative periods for the management of PSP. We reviewed the literature to identify randomized controlled trials evaluating the efficacy of these psychotherapy approaches on pain-related surgical outcomes. MATERIALS AND METHODS: We searched Medline, Medline-In-Process, Embase and Embase Classic, and PsycInfo to identify studies meeting our search criteria. After title and abstract review, selected articles were rated for risk of bias. RESULTS: Six papers based on five trials (four back surgery, one cardiac surgery) met our inclusion criteria. Four papers employed CBT and two CBT-physiotherapy variant; no ACT or mindfulness-based studies were identified. Considerable heterogeneity was observed in the timing and delivery of psychological interventions and length of follow-up (1 week to 2-3 years). Whereas pain-intensity reporting varied widely, pain disability was reported using consistent methods across papers. The majority of papers (four of six) reported reduced pain intensity, and all relevant papers (five of five) found improvements in pain disability. General limitations included lack of large-scale data and difficulties with blinding. CONCLUSION: This systematic review provides preliminary evidence that CBT-based psychological interventions reduce PSP intensity and disability. Future research should further clarify the efficacy and optimal delivery of CBT and newer psychological approaches to PSP.

Hyperbaric Oxygen Therapy: A New Treatment for Chronic Pain?

BACKGROUND AND OBJECTIVE: Hyperbaric oxygen therapy (HBOT) is a treatment providing 100% oxygen at a pressure greater than that at sea level. HBOT is becoming increasingly recognized as a potential treatment modality for a broad range of ailments, including chronic pain. In this narrative review, we discuss the current understanding of pathophysiology of nociceptive, inflammatory and neuropathic pain, and the body of animal studies addressing mechanisms by which HBOT may ameliorate these different types of pain. Finally, we review clinical studies suggesting that HBOT may be useful in treating chronic pain syndromes, including chronic headache, fibromyalgia, complex regional pain syndrome, and trigeminal neuralgia. DATABASE AND DATA TREATMENT: A comprehensive search through MEDLINE, EMBASE, Scopus, and Web of Science for studies relating to HBOT and pain was performed using the following keywords: hyperbaric oxygen therapy or hyperbaric oxygen treatment (HBOT), nociceptive pain, inflammatory pain, neuropathic pain, HBOT AND pain, HBOT AND headache, HBOT AND fibromyalgia, HBOT AND complex regional pain syndrome, and HBOT AND trigeminal neuralgia. RESULTS: Twenty-five studies examining the role of HBOT in animal models of pain and human clinical trials were found and reviewed for this narrative review. CONCLUSIONS: HBOT has been shown to reduce pain using animal models. Early clinical research indicates HBOT may also be useful in modulating human pain; however, further studies are required to determine whether HBOT is a safe and efficacious treatment modality for chronic pain conditions.

Use of preoperative antidepressants is not associated with postoperative hospital length of stay.

PURPOSE: Antidepressant medications are commonly prescribed for the treatment of depression, anxiety, and chronic pain. Their use may lead to a number of side effects with important implications in the perioperative period. Our aim was to examine the effect of preoperative antidepressant administration on post-surgical hospital length of stay (LOS) in elective non-cardiac surgery patients. DESIGN: Historical cohort study. METHODS: Demographic and preoperative data were collected by chart review for all non-cardiac surgery patients who were assessed in the preoperative consult clinic from April 2008 through February 2009. Patients were grouped according to whether or not they were taking antidepressant medications. Median length of stay was compared between patients who took antidepressants preoperatively and those who did not. RESULTS: Data were collected for 3,692 patients. Two hundred eighty-nine (7.8%) patients were taking antidepressants preoperatively. Use of antidepressants was not associated with an increased hospital LOS. The median LOS was four days both for patients who took antidepressants preoperatively (95% confidence interval [CI] 4 to 4) and for those who did not (95% CI 3 to 5) (P = 0.13). CONCLUSIONS: The preoperative use of antidepressant medications was not associated with increased postoperative hospital LOS following elective non-cardiac surgery.

A nonsynonymous polymorphism of IRAK4 associated with increased prevalence of gram-positive infection and decreased response to toll-like receptor ligands.

Mutations in IRAK4 have been associated with recurrent Gram-positive infections in children. Given the central role of IRAK4 in innate immunity signaling, we hypothesized that common genetic variants of IRAK4 may be associated with prevalence of Gram-positive infection in critically ill adults. Haplotype clade tag single nucleotide polymorphisms (SNPs) of the IRAK4 gene were selected and genotyped in a cohort of 1,029 critically ill patients with systemic inflammatory response syndrome (SIRS). We found that a haplotype clade tagged by the A allele of the htSNP G29429A (Ala428Thr) was associated with increased relative risk of Gram-positive infection at admission to ICU (RR = 1.2, p < 0.05). Furthermore, the 29429A allele was associated with decreased lymphoblastoid cell response to CpG (as measured by IL-6 production) (raw values ± 95% CI 40.3 ± 32.3 vs. 85.8 ± 29.4 pg/ml; log-transformed values ± 95% CI 1.13 ± 0.37 vs. 1.55 ± 0.18, p < 0.04). We also found that IRAK4-deficient fibroblasts transfected with an IRAK4 expression plasmid containing the 29429A allele produced less IL-6 in response to lipopolysaccharide (p = 0.07). Our data suggest that the IRAK4 haplotype clade marked by 29429A (428Thr) alters susceptibility to Gram-positive bacteria, by decreasing cellular response to TLR ligands.

Hospital administrative database underestimates delirium rate after cardiac surgery.

PURPOSE: Administrative electronic databases are highly specific for postoperative complications, but they lack sensitivity. The objective of this study was to determine the incidence of delirium after cardiac surgery using a targeted prospectively collected dataset and to compare the findings with the incidence of delirium in the same cohort of patients identified in a hospital administrative database. METHODS: Following Research Ethics Board approval, we compared delirium rates in a prospectively collected data research database with delirium rates in the same cohort of patients in an administrative hospital database where delirium was identified from codes entered by coding and abstracting staff. Every 12 hr postoperatively, delirium was assessed with a Confusion Assessment Method in the Intensive Care Unit. The administrative database contained the International Classification of Diseases version 10 (ICD-10) codes for patient diagnoses. The ICD-10 codes were extracted from the administrative database for each patient in the research database and were checked for the presence of the ICD-10 code for delirium. RESULTS: Data from a cohort of 1,528 patients were analyzed. Postoperative delirium was identified in 182 (11.9%) patients (95% confidence interval [CI], 10.3-13.5%) in the research dataset and 46 (3%) patients (95% CI, 2.2-3.8%) in the administrative dataset (P < 0.001). Thirteen (0.85%) patients who were coded for delirium in the administrative database were not identified in the research dataset. The median onset of postoperative delirium in these patients was significantly delayed (4 [3-9] days) compared with patients identified by both datasets (2 [1-9] days) and compared with patients from the research database only (1 [1-14] days) (P = 0.007). CONCLUSION: Postoperative delirium rates after cardiac surgery are underestimated by the hospital administrative database.

Bench-to-bedside review: Association of genetic variation with sepsis.

Susceptibility and response to infectious disease is, in part, heritable. Initial attempts to identify the causal genetic polymorphisms have not been entirely successful because of the complexity of the genetic, epigenetic, and environmental factors that influence susceptibility and response to infectious disease and because of flaws in study design. Potential associations between clinical outcome from sepsis and many inflammatory cytokine gene polymorphisms, innate immunity pathway gene polymorphisms, and coagulation cascade polymorphisms have been observed. Confirmation in large, well conducted, multicenter studies is required to confirm current findings and to make them clinically applicable. Unbiased investigation of all genes in the human genome is an emerging approach. New, economical, high-throughput technologies may make this possible. It is now feasible to genotype thousands of tag single nucleotide polymorphisms across the genome in thousands of patients, thus addressing the issues of small sample size and bias in selecting candidate polymorphisms and genes for genetic association studies. By performing genome-wide association studies, genome-wide scans of nonsynonymous single nucleotide polymorphisms, and testing for differential allelic expression and copy number polymorphisms, we may yet be able to tease out the complex influence of genetic variation on susceptibility and response to infectious disease.

Novel polymorphism of interleukin-18 associated with greater inflammation after cardiac surgery.

INTRODUCTION: Interleukin (IL)-18 is a key modulator of the cytokine response that leads to organ dysfunction and prolonged intensive care unit (ICU) stay after cardiopulmonary bypass surgery. We hypothesised that variation in the pro-inflammatory gene IL-18 is associated with adverse clinical outcome because of a more intense inflammatory response. METHODS: Haplotypes of the IL-18 gene were inferred from genotypes of 23 Coriell Registry subjects. Four haplotype tag single nucleotide polymorphisms (-607 C/A, -137 G/C, 8148 C/T and 9545 T/G) identified four major haplotype clades. These polymorphisms were genotyped in 658 Caucasian patients undergoing cardiopulmonary bypass surgery. Clinical phenotypes were collected by retrospective chart review. RESULTS: Patients homozygous for the T allele of the 9545 T/G polymorphism had an increased occurrence of prolonged ICU stay (6.8% for TT genotype versus 2.7% for GG or GT genotype; p = 0.015). Patients homozygous for the T allele also had increased occurrence of low systemic vascular resistance index (62%) compared with the GG and GT genotypes (53%; p = 0.045). Patients homozygous for the T allele had increased serum IL-18 concentrations 24 hours post-surgery (p = 0.018), increased pro-inflammatory tumour necrosis factor alpha concentrations (p = 0.014) and decreased anti-inflammatory serum IL-10 concentrations (p = 0.018) 24 hours post-surgery. CONCLUSIONS: The TT genotype of the IL-18 9545 T/G polymorphism is associated with an increased occurrence of prolonged ICU stay post-surgery and greater post-surgical inflammation. These results may be explained by greater serum IL-18, leading to greater pro-versus anti-inflammatory cytokine expression.

Fibrinogen-beta gene haplotype is associated with mortality in sepsis.

OBJECTIVES: Fibrinogen plays a key role in coagulation and inflammation. Transcription of the fibrinogen-beta gene (FGB) is the rate-limiting step in fibrinogen production. Our aim was to determine whether haplotypes of FGB are associated with mortality and organ dysfunction in a cohort of patients with sepsis. METHODS: A prospective cohort of 631 consecutive Caucasian patients with sepsis from a tertiary care medical-surgical ICU were enrolled in a gene association study. Patients were genotyped for three polymorphisms in FGB: -854 G/A, -455 G/A, and +9006 G/A. Haplotypes were inferred using PHASE. The primary outcome was mortality. Secondary outcomes were severity of organ dysfunction as measured by days alive and free (DAF) of organ dysfunction. RESULTS: Haplotype GAA was associated with a significantly lower 28-day mortality (28.9% vs. 36.9% for all other haplotypes, p=0.03). Carriers of two copies of haplotype GAA (vs. one and zero copies) had more DAF of organ dysfunction. In a multivariate analysis, haplotype GAA was an independent predictor for lower mortality (OR=0.66, 95% CI=0.46-0.94, p=0.02). CONCLUSIONS: Haplotype GAA in FGB is associated with lower mortality and lower severity of organ dysfunction. Haplotype GAA encompasses a previously described haplotype -1420A/-854G/-455A/-249C/-148T/+1690G that is associated with higher fibrinogen levels.

Issues with polymorphism analysis in sepsis.

Genetic variation has been shown to play a large role in determining susceptibility to and outcome of such complex diseases as sepsis. There is a much higher heritability of death due to infection than death due to cancer or heart disease. More than 8 million single nucleotide polymorphisms (SNPs) have been detected in the human genome, and there is very little understanding of their effect on gene expression and protein function. The use of haplotypes, which are inherited sets of linked SNPs, as the unit of genetic variation in association studies and the marking of these haplotypes with unique "tag SNPs" may help to narrow down the search for causal SNPs. Future studies must be large (thousands of patients) and must be carefully designed to avoid false associations resulting from ethnic differences in genotype frequencies and disease prevalence in order to find true, reproducible associations between genotype and phenotype. Functional studies and careful characterization of intermediate phenotypes must be done to lend biological plausibility to genotype-phenotype associations. Examination of the association between genetic polymorphisms and sepsis promises to provide clinicians with new tools to evaluate prognosis, to intervene early and aggressively in treating high-risk persons, and to avoid the use of therapies with adverse effects in treating low-risk persons.

Polymorphisms in CD14, mannose-binding lectin, and Toll-like receptor-2 are associated with increased prevalence of infection in critically ill adults.

OBJECTIVE: To test for the association of single nucleotide polymorphisms of the innate immunity receptors cluster of differentiation (CD)-14, mannose-binding lectin, and Toll-like receptor-2 with clinical phenotype in critically ill patients with systemic inflammatory response syndrome. DESIGN: Genetic association study. SETTING: Tertiary care mixed medical-surgery intensive care unit at St. Paul's Hospital, Vancouver, BC, a teaching hospital associated with the University of British Columbia. PATIENTS: A cohort of 252 critically ill Caucasians with systemic inflammatory response syndrome. INTERVENTIONS: DNA was extracted from discarded blood. Clinical data were gathered by retrospective chart review. MEASUREMENTS AND MAIN RESULTS: C-159T CD14, the X/Y and B, C, and D polymorphisms of mannose-binding lectin, and T-16933A Toll-like receptor-2 were genotyped using polymerase chain reaction-restriction fragment length polymorphism. We tested for association of genotype with prevalence of positive bacterial cultures, type of organism (Gram-positive, Gram-negative, other), sepsis and septic shock at admission to the intensive care unit, and 28-day survival. CD14 -159TT was associated with increased prevalence of positive bacterial cultures and with Gram-negative bacteria. Mannose-binding lectin haplotype pairs XO/O and O/O were also associated with increased prevalence of positive bacterial cultures but not with a specific organism class. Toll-like receptor-2 -16933AA was associated with increased prevalence of sepsis and with Gram-positive bacteria. In contrast, the polymorphisms were not associated with increased prevalence of septic shock or altered 28-day survival. CONCLUSIONS: Single nucleotide polymorphisms in CD14, mannose-binding lectin, and Toll-like receptor-2 are associated with increased prevalence of positive bacterial cultures and sepsis but not with altered prevalence of septic shock or decreased 28-day survival. Furthermore, CD14 single nucleotide polymorphisms were associated with Gram-negative bacteria and Toll-like receptor-2 with Gram-positive bacteria, whereas mannose-binding lectin was not associated with a particular organism class. Thus, single nucleotide polymorphisms in innate immunity receptors may alter recognition and clearance of bacteria without changing outcomes of critically ill adults with systemic inflammatory response syndrome.

The association of interleukin 6 haplotype clades with mortality in critically ill adults.

BACKGROUND: Interleukin 6 (IL-6) is a key proinflammatory cytokine in the systemic inflammatory response syndrome (SIRS). A G-->C polymorphism at position -174 of the IL-6 gene is associated with an adverse outcome in a number of inflammatory diseases, although its association with sepsis as an outcome remains unclear. We tested the hypothesis that specific haplotype clades of IL-6 may be associated with an outcome of SIRS. METHODS: We studied a cohort of 228 critically ill white patients who met at least 2 of 4 SIRS criteria. Clinical data were collected over 28 days after hospital admission. Haplotypes of IL-6 were inferred from publicly available data using PHASE (software for haplotype reconstruction and recombination rate estimation from population data), and cladistic structure was determined using Molecular Evolutionary Genetic Analyses (MEGA2) software. Then, a minimum set of "haplotype tag" single nucleotide polymorphisms (-174G/C, 1753C/G, and 2954G/C) that defined all 4 major haplotype clades of the IL-6 gene was chosen for further genotyping. RESULTS: Patients who had 2 copies of haplotypes from within the haplotype clades -174C/1753C/2954G (C/C/G), G/G/G, or G/C/C had a greater 28-day mortality compared with patients who carried 1 or no copies of these haplotypes (40.0% vs 26.0%; P = .02). These patients also had fewer days alive and free of multiple system organ dysfunction (P<.05). There were no associations between individual single nucleotide polymorphisms (including -174G/C) and survival or organ dysfunction. CONCLUSIONS: The C/C/G, G/G/G, and G/C/C haplotype clades of IL-6 were strongly associated with increased mortality and more organ dysfunction in a cohort of critically ill patients who had SIRS. Haplotype-based analysis succeeded in identifying this association, whereas individual single nucleotide polymorphism-based analysis failed.