Do heart and respiratory rate variability improve prediction of extubation outcomes in critically ill patients?

INTRODUCTION: Prolonged ventilation and failed extubation are associated with increased harm and cost. The added value of heart and respiratory rate variability (HRV and RRV) during spontaneous breathing trials (SBTs) to predict extubation failure remains unknown. METHODS: We enrolled 721 patients in a multicenter (12 sites), prospective, observational study, evaluating clinical estimates of risk of extubation failure, physiologic measures recorded during SBTs, HRV and RRV recorded before and during the last SBT prior to extubation, and extubation outcomes. We excluded 287 patients because of protocol or technical violations, or poor data quality. Measures of variability (97 HRV, 82 RRV) were calculated from electrocardiogram and capnography waveforms followed by automated cleaning and variability analysis using Continuous Individualized Multiorgan Variability Analysis (CIMVA™) software. Repeated randomized subsampling with training, validation, and testing were used to derive and compare predictive models. RESULTS: Of 434 patients with high-quality data, 51 (12%) failed extubation. Two HRV and eight RRV measures showed statistically significant association with extubation failure (P <0.0041, 5% false discovery rate). An ensemble average of five univariate logistic regression models using RRV during SBT, yielding a probability of extubation failure (called WAVE score), demonstrated optimal predictive capacity. With repeated random subsampling and testing, the model showed mean receiver operating characteristic area under the curve (ROC AUC) of 0.69, higher than heart rate (0.51), rapid shallow breathing index (RBSI; 0.61) and respiratory rate (0.63). After deriving a WAVE model based on all data, training-set performance demonstrated that the model increased its predictive power when applied to patients conventionally considered high risk: a WAVE score >0.5 in patients with RSBI >105 and perceived high risk of failure yielded a fold increase in risk of extubation failure of 3.0 (95% confidence interval (CI) 1.2 to 5.2) and 3.5 (95% CI 1.9 to 5.4), respectively. CONCLUSIONS: Altered HRV and RRV (during the SBT prior to extubation) are significantly associated with extubation failure. A predictive model using RRV during the last SBT provided optimal accuracy of prediction in all patients, with improved accuracy when combined with clinical impression or RSBI. This model requires a validation cohort to evaluate accuracy and generalizability. TRIAL REGISTRATION: ClinicalTrials.gov NCT01237886. Registered 13 October 2010.

Feasibility of implementing Extubation Advisor, a clinical decision support tool to improve extubation decision-making in the ICU: a mixed-methods observational study.

OBJECTIVES: Although spontaneous breathing trials (SBTs) are standard of care to extubation readiness, no tool exists that optimises prediction and standardises assessment. In this study, we evaluated the feasibility and clinical impressions of Extubation Advisor (EA), a comprehensive clinical extubation decision support (CDS) tool. DESIGN: Phase I mixed-methods observational study. SETTING: Two Canadian intensive care units (ICUs). PARTICIPANTS: We included patients on mechanical ventilation for ≥24 hours and clinicians (respiratory therapists and intensivists) responsible for extubation decisions. INTERVENTIONS: Components included a predictive model assessment, feasibility evaluation, questionnaires and interviews with clinicians. RESULTS: We enrolled 117 patients, totalling 151 SBTs and 80 extubations. The incidence of extubation failure was 11% in low-risk patients and 21% in high-risk patients stratified by the predictive model; 38% failed extubation when both the model and clinical impression were at high risk. The tool was well rated: 94% and 75% rated the data entry and EA report as average or better, respectively. Interviews (n=15) revealed favourable impressions regarding its user interface and functionality, but unexpectedly, also concerns regarding EA's potential impact on respiratory therapists' job security. CONCLUSIONS: EA implementation was feasible, and users perceived it to have potential to support extubation decision-making. This study helps to understand bedside implementation of CDS tools in a multidisciplinary ICU. TRIAL REGISTRATION NUMBER: NCT02988167.

Adjuvant melatonin for the prevention of recurrence and mortality following lung cancer resection (AMPLCaRe): A randomized placebo controlled clinical trial.

BACKGROUND: Despite curative intent resection in patients with non-small cell lung cancer (NSCLC), recurrence leading to mortality remains too common. Melatonin has shown promise for the treatment of patients with lung cancer; however, its effect following cancer resection has not been studied. We evaluated if melatonin taken after complete resection reduces lung cancer recurrence and mortality, or impacts quality of life (QOL), symptomatology or immune function. METHODS: Participants received melatonin (20 mg) or placebo nightly for one year following surgical resection of primary NSCLC. The primary outcome was two-year disease-free survival (DFS). Secondary outcomes included five-year DFS, adverse events, QOL, fatigue, sleep, depression, anxiety, pain, and biomarkers assessing for immune function/inflammation. This study is registered at https://clinicaltrials.gov NCT00668707. FINDINGS: 709 patients across eight centres were randomized to melatonin (n = 356) versus placebo (n = 353). At two years, melatonin showed a relative risk of 1·01 (95% CI 0·83-1·22), p = 0·94 for DFS. At five years, melatonin showed a hazard ratio of 0·97 (95% CI 0·86-1·09), p = 0·84 for DFS. When stratified by cancer stage (I/II and III/IV), a hazard reduction of 25% (HR 0·75, 95% CI 0·61-0·92, p = 0·005) in five-year DFS was seen for participants in the treatment arm with advanced cancer (stage III/IV). No meaningful differences were seen in any other outcomes. INTERPRETATION: Adjuvant melatonin following resection of NSCLC does not affect DFS for patients with resected early stage NSCLC, yet may increase DFS in patients with late stage disease. Further study is needed to confirm this positive result. No beneficial effects were seen in QOL, symptoms, or immune function. FUNDING: This study was funded by the Lotte and John Hecht Memorial Foundation and the Gateway for Cancer Research Foundation.

Incidence of lateral femoral cutaneous nerve neuropraxia after anterior approach hip arthroplasty.

BACKGROUND: Although injury to the lateral femoral cutaneous nerve (LFCN) is a known complication of anterior approaches to the hip and pelvis, no study has quantified its' incidence in anterior arthroplasty procedures. QUESTIONS/PURPOSES: We therefore defined the incidence, functional impact, and natural history of LFCN neuropraxia after an anterior approach for both hip resurfacing (HR) and primary total hip arthroplasty (THA). METHODS: We followed 132 patients who underwent an anterior hip approach (55 THA; 77 HR). We administered self-reported questionnaires for sensory deficits of LFCN, neuropathic pain score (DN4), visual analog scale, as well as SF-12, UCLA, and WOMAC scores at one year postoperatively. A subset of 60 patients (30 THA; 30 HR) was evaluated at two time intervals. RESULTS: One hundred seven patients (81%) reported LFCN neuropraxia with a mean severity score of 2.32/10 and a mean DN4 score of 2.42/10. Hip resurfacing had a higher incidence of neuropraxia as compared with THA: 91% versus 67%, respectively. No functional limitations were reported on SF-12, WOMAC, or UCLA scores. Of the subset of 60 patients followed over an average of 12 months, 53 (88%) reported neuropraxia at the first followup interval with only three (6%) having complete resolution at second followup. Improvement in DN4 scores was observed over time: 3.6 versus 2.5, respectively. CONCLUSIONS: Although LFCN neuropraxia was a frequent complication after anterior approach THA, it did not lead to functional limitations in our patients. A decrease in symptoms occurred over time but only a small number of patients reported complete resolution. LEVEL OF EVIDENCE: Level III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Incidence of groin pain after metal-on-metal hip resurfacing.

UNLABELLED: Metal-on-metal hip resurfacing is offered as an alternative to traditional THA for the young and active adult with advanced osteoarthritis. However, patients undergoing hip resurfacing may be predisposed to persistent groin pain due to insufficient head/neck offset, an uncovered acetabular component, or both. We therefore determined the incidence of groin pain after metal-on-metal hip resurfacing, its impact on patient function, and possible risk factors contributing to groin pain. We evaluated 116 patients with a followup of at least 12 months after surgery (mean, 26 months; range, 12-61 months). The mean age was 48.8 years (range, 24.0-66.3 years), with 21 women (18%) and 95 men (82%). All patients were evaluated clinically and radiographically and had a Harris hip score, WOMAC, UCLA Activity Rating Scale, and the RAND-36 General Health measure; they were specifically asked if they experienced groin pain currently or since their surgery. Although all patients had functional improvements postoperatively, 21 of 116 of the patients (18%) reported groin pain; 12 of these (10% of the total) stated the pain limited their activities of daily living and 11 (10%) required medication for pain. Female patients were at greater risk of having groin pain. Of the patients with groin pain, three patients had muscle atrophy with a joint effusion on CT; one of these patients had revision surgery for the pain. Patients with metal-on-metal resurfacing may have a higher incidence of pain than those with conventional THA. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Intervention Development Process for a Pragmatic Randomized Controlled Trial: The Thoracic Peri-Operative Integrative Surgical Care Evaluation Trial.

BACKGROUND: Use of complementary therapies is high among people with cancer despite research gaps. The Thoracic Peri-Operative Integrative Surgical Care Evaluation (POISE) Trial will evaluate the impact of an integrative care intervention delivered by naturopathic doctors (NDs) in conjunction with usual care for patients undergoing surgery for lung, gastric, and esophageal cancer. OBJECTIVES: To describe the multistep, multidisciplinary process of defining the integrative care intervention to be used in the Thoracic POISE trial using a principle-based approach that is pragmatic, holistic, safe, feasible, evidence driven, and consensus based. METHODS: An Intervention Development Committee (IDC) made up of a multidisciplinary team of health care providers (NDs, surgeons, oncologists, nurses, dietitians, physiotherapists, pharmacists, and psychologists), researchers, and patients was established to oversee the process. Potential intervention components were identified through a clinical practice survey and expert opinion. Systematic literature reviews were conducted and scores assigned based on the following criteria: usage, safety, goals, feasibility/scalability, and evidence. The IDC selected an intervention to be piloted that consists of a standard palette including core and optional components. Safety, known risks, and interactions with pharmaceuticals were evaluated using industry and professional monographs, a scoping literature review, and consultations with hospital pharmacists. RESULTS: The clinical practice survey and expert opinion identified 28 components for consideration. Following literature reviews, scoring, consensus from the IDC, and safety and interaction considerations, an intervention palette consisting of core and optional components was defined. The intervention options vary based on the patient's phase of treatment and symptom-specific needs. The intervention includes supplements, physical recommendations (exercise), nutritional counseling, and psychological support (audio scripts). CONCLUSION: Through a multistep, multidisciplinary process an integrative care intervention was developed for the Thoracic POISE trial. The intervention will be piloted in a single-arm feasibility study, followed by a single-center randomized controlled trial (RCT), and finally a multicenter RCT.

A prospective metal ion study of large-head metal-on-metal bearing: a matched-pair analysis of hip resurfacing versus total hip replacement.

The current study measured ion release among large-head metal-on-metal hip bearings. Twenty-six patients with a modular, Profemur® TL with A-Class® big femoral head total hip replacement were matched (gender, femoral size, BMI) with a group of 26 patients with the Conserve® Plus implant hip resurfacing. Compared with HR patients, THR patients had higher median serum cobalt ion levels at 6 months (3.26 vs 1.12 µg/L, P = .002) 1 year (4.51 vs 1.02, P = .002), and 2 years (3.77 vs 1.22, P<.001) following surgery. No differences in chromium ions were observed. Further research is required to determine the clinical significance of elevated serum cobalt ions.

Cognitive dysfunction after total knee arthroplasty: effects of intraoperative cerebral embolization and postoperative complications.

Cerebral emboli identified as high-intensity transient signals (HITS) occur during total knee arthroplasty (TKA). Their effects on cognitive outcome remain speculative. Intraoperative HITS and postoperative complications were correlated with the cognitive function of TKA patients. Cognitive function was assessed both before and after surgery (1 week and 3 months). High-intensity transient signals occurred in 22 of 37 patients. Counts of HITSs were higher in patients with sonographically detected intracardiac shunts. Cognitive dysfunction was found in 41% of patients at 1 week, but in only 18% at 3 months. High-intensity transient signal counts were not associated with the prevalence of cognitive deficits. At 1 week, 58% of patients with cognitive deficits had at least 1 postoperative complication (6% in nondeficit patients). All cognitively impaired patients at 3 months had complications (17% in the nondeficit group). This raises the possibility that postoperative complications might be associated with cognitive dysfunction in TKA patients.

Autologous osteoarticular transfer from the proximal tibiofibular joint to the scaphoid and lunate facets in the treatment of severe distal radial fractures: a report of two cases.

PURPOSE: This study was conducted to determine the appropriateness of using the articular cartilaginous surfaces of the proximal tibiofibular joint to resurface damaged distal radial articular surfaces and to assess the clinical results in the first 2 patients. METHOD: Cadaveric specimens of the facets of the proximal tibiofibular joints and distal radius were sized and compared. Two patients underwent transfer of a fibular facet. RESULTS: The surface area of each of the proximal tibiofibular facets were larger than either the scaphoid or lunate facets of the distal radius. The 2 patients had excellent clinical results with minimal donor morbidity. CONCLUSIONS: Use of the articular surfaces from the proximal tibiofibular joint to replace damaged distal radial facets is possible and can be accomplished with excellent results and minimal morbidity.