Early dynamic changes to monocytes following major surgery are associated with subsequent infections.

Background: Post-operative infections are a common cause of morbidity following major surgery. Little is understood about how major surgery perturbs immune function leading to heightened risk of subsequent infection. Through analysis of paired blood samples obtained immediately before and 24 h following surgery, we evaluated changes in circulating immune cell phenotype and function across the first 24 h, to identify early immune changes associated with subsequent infection. Methods: We conducted a prospective observational study of adult patients undergoing major elective gastrointestinal, gynecological, or maxillofacial surgery requiring planned admission to the post-anesthetic care unit. Patients were followed up to hospital discharge or death. Outcome data collected included mortality, length of stay, unplanned intensive care unit admission, and post-operative infections (using the standardized endpoints in perioperative medicine-core outcome measures for perioperative and anesthetic care criteria). Peripheral blood mononuclear cells were isolated prior to and 24 h following surgery from which cellular immune traits including activation and functional status were assessed by multi-parameter flow cytometry and serum immune analytes compared by enzyme-linked immunosorbent assay (ELISA). Results: Forty-eight patients were recruited, 26 (54%) of whom developed a post-operative infection. We observed reduced baseline pre- and post-operative monocyte CXCR4 and CD80 expression (chemokine receptors and co-stimulation markers, respectively) in patients who subsequently developed an infection as well as a profound and selective post-operative increase in CD4+ lymphocyte IL-7 receptor expression in the infection group only. Higher post-operative monocyte count was significantly associated with the development of post-operative infection (false discovery rate < 1%; adjusted p-value = 0.001) with an area under the receiver operating characteristic curve of 0.84 (p < 0.0001). Conclusion: Lower monocyte chemotaxis markers, higher post-operative circulating monocyte counts, and reduced co-stimulatory signals are associated with subsequent post-operative infections. Identifying the underlying mechanisms and therapeutics to reverse defects in immune cell function requires further exploration.

Preoperative aerobic fitness and perioperative outcomes in patients undergoing cystectomy before and after implementation of a national lockdown.

Background: Lower fitness is a predictor of adverse outcomes after radical cystectomy. Lockdown measures during the COVID-19 pandemic affected daily physical activity. We hypothesised that lockdown during the pandemic was associated with a reduction in preoperative aerobic fitness and an increase in postoperative complications in patients undergoing radical cystectomy. Methods: We reviewed routine preoperative cardiopulmonary exercise testing (CPET) data collected prior to the pandemic (September 2018 to March 2020) and after lockdown (March 2020 to July 2021) in patients undergoing radical cystectomy. Differences in CPET variables, Postoperative Morbidity Survey (POMS) data, and length of hospital stay were compared. Results: We identified 267 patients (85 pre-lockdown and 83 during lockdown) who underwent CPET and radical cystectomy. Patients undergoing radical cystectomy throughout lockdown had lower ventilatory anaerobic threshold (9.0 [7.9-10.9] vs 10.3 [9.1-12.3] ml kg-1 min-1; P=0.0002), peak oxygen uptake (15.5 [12.9-19.1] vs 17.5 [14.4-21.0] ml kg-1 min-1; P=0.015), and higher ventilatory equivalents for carbon dioxide (34.7 [31.4-38.5] vs 33.4 [30.5-36.5]; P=0.030) compared with pre-lockdown. Changes were more pronounced in males and those aged >65 yr. Patients undergoing radical cystectomy throughout lockdown had a higher proportion of day 5 POMS-defined morbidity (89% vs 75%, odds ratio [OR] 2.698, 95% confidence interval [CI] 1.143-6.653; P=0.019), specifically related to pulmonary complications (30% vs 13%, OR 2.900, 95% CI 1.368-6.194; P=0.007) and pain (27% vs 9%, OR 3.471, 95% CI 1.427-7.960; P=0.004), compared with pre-lockdown on univariate analysis. Conclusions: Lockdown measures in response to the COVID-19 pandemic were associated with a reduction in fitness and an increase in postoperative morbidity among patients undergoing radical cystectomy.

Objective assessment of metabolism and guidance of ICU rehabilitation with cardiopulmonary exercise testing.

PURPOSE OF REVIEW: Addressing the reduced quality of life that affects ICU survivors is the most pressing challenge in critical care medicine. In order to meet this challenge, we must translate lessons learnt from assessing and training athletes to the clinical population, utilizing measurable and targeted parameters obtained during cardiopulmonary exercise testing (CPET). RECENT FINDINGS: Critical illness survivors demonstrate a persistent reduction in their physical and metabolic function. This manifests in reduced aerobic exercise capacity and metabolic inflexibility. CPET-guided targeted metabolic conditioning has proved beneficial in several clinical populations, including those undergoing high-risk surgery, and could be successfully applied to the rehabilitation of ICU survivors. SUMMARY: CPET shows great promise in the guidance of rehabilitation in functionally limited ICU survivors. Parallels in the physiological response to exercise in athletes and clinical populations with the stress and consequences of critical illness must be investigated and ultimately applied to the burgeoning population of ICU survivors in order to treat the consequences of survival from critical illness.

Assessments of frailty in bladder cancer.

BACKGROUND AND AIMS: The incidence of frailty is increasing as the population ages, which has important clinical implications given the associations between frailty and poor outcomes in the bladder cancer population. Due to a multi-organ system decline and decreased physiologic reserve, frail patients are vulnerable to stressors of disease and have poorer mortality and morbidity rates than their nonfrail peers. The association between frailty and poor outcomes has been documented across multiple populations, including radical cystectomy, creating a need for frailty assessments to be used preoperatively for risk stratification. We aim to provide a review of the common frailty assessments and their relevance to radical cystectomy patients. FINDINGS: A variety of assessments for frailty exist, from short screening items to comprehensive geriatric assessments. The syndrome spans multiple organ systems, as do the potential diagnostic instruments. Some instruments are less practical for use in clinical practice by urologists, such as the Canadian Study of Health and Aging Frailty Index and Comprehensive Geriatric Assessment. The tool most studied in radical cystectomy is the modified Frailty Index, associated with high grade complications and 30-days mortality. Frailty often coexists with malnutrition and sarcopenia, stressing the importance of screening for and addressing these syndromes to improve patient's perioperative outcomes. CONCLUSIONS: There is no universally agreed upon frailty assessment, but the most studied in radical cystectomy is the modified Frailty Index, providing valuable data with which to counsel patients preoperatively. Alterations in immune phenotypes provide potential future diagnostic biomarkers for frailty.

The MARBLE Study Protocol: Modulating ApoE Signaling to Reduce Brain Inflammation, DeLirium, and PostopErative Cognitive Dysfunction.

BACKGROUND: Perioperative neurocognitive disorders (PND) are common complications in older adults associated with increased 1-year mortality and long-term cognitive decline. One risk factor for worsened long-term postoperative cognitive trajectory is the Alzheimer's disease (AD) genetic risk factor APOE4. APOE4 is thought to elevate AD risk partly by increasing neuroinflammation, which is also a theorized mechanism for PND. Yet, it is unclear whether modulating apoE4 protein signaling in older surgical patients would reduce PND risk or severity. OBJECTIVE: MARBLE is a randomized, blinded, placebo-controlled phase II sequential dose escalation trial designed to evaluate perioperative administration of an apoE mimetic peptide drug, CN-105, in older adults (age≥60 years). The primary aim is evaluating the safety of CN-105 administration, as measured by adverse event rates in CN-105 versus placebo-treated patients. Secondary aims include assessing perioperative CN-105 administration feasibility and its efficacy for reducing postoperative neuroinflammation and PND severity. METHODS: 201 patients undergoing non-cardiac, non-neurological surgery will be randomized to control or CN-105 treatment groups and receive placebo or drug before and every six hours after surgery, for up to three days after surgery. Chart reviews, pre- and postoperative cognitive testing, delirium screening, and blood and CSF analyses will be performed to examine effects of CN-105 on perioperative adverse event rates, cognition, and neuroinflammation. Trial results will be disseminated by presentations at conferences and peer-reviewed publications. CONCLUSION: MARBLE is a transdisciplinary study designed to measure CN-105 safety and efficacy for preventing PND in older adults and to provide insight into the pathogenesis of these geriatric syndromes.

Effects of Acetaminophen, NSAIDs, Gabapentinoids, and Their Combinations on Postoperative Pulmonary Complications After Total Hip or Knee Arthroplasty.

OBJECTIVE: Multimodal analgesia has gained popularity in total hip arthroplasty (THA) and total knee arthroplasty (TKA), but large multicenter studies evaluating specific analgesic combinations are lacking. DESIGN: A retrospective study using the Premier Healthcare Database (2009-2014). SUBJECTS: Adults who underwent elective primary THA or TKA. METHODS: We categorized day-of-surgery analgesic exposure using eight mutually exclusive categories: acetaminophen (Ac), nonsteroidal anti-inflammatory drugs (Ns), gabapentinoids (Ga; gabapentin or pregabalin), Ac+Ns, Ac+Ga, Ns+Ga, Ac+Ns+Ga, and none of the three drugs. Multilevel models measured associations of the analgesic categories with a composite of postoperative pulmonary complications (PPCs). RESULTS: Among 863,139 patients, 75.2% received at least one of the three drugs. In multilevel models, compared with none of the three drugs, Ga use was associated with increased odds of PPCs when used alone (adjusted odds ratio [aOR] = 1.35, 95% confidence interval [CI] = 1.27 to 1.44), combined with Ac (aOR = 1.16, 95% CI = 1.08 to 1.26), or combined with Ns (aOR = 1.28, 95% CI = 1.21 to 1.34). In contrast, the Ac+Ns pair was associated with decreased odds of PPCs (OR = 0.86, 95% CI = 0.83 to 0.90) and lower opioid consumption. Ac+Ns+Ga was not associated with PPCs, whereas it was associated with the lowest opioid consumption on the day of surgery. CONCLUSIONS: Gabapentinoids, alone and in single combination with either acetaminophen or nonsteroidal anti-inflammatory drugs, were associated with higher PPCs, whereas the Ac+Ns pair was associated with fewer PPCs and an opioid-sparing effect. Ac+Ns+Ga was not associated with PPCs, whereas it was associated with the lowest opioid consumption on the day of surgery.

Dose-Dependent Association of Gabapentinoids with Pulmonary Complications After Total Hip and Knee Arthroplasties.

BACKGROUND: Gabapentinoids are commonly prescribed in perioperative multimodal analgesia protocols. Despite widespread use, the optimal dose to reduce opioid consumption while minimizing risks is unknown. We assessed dose-dependent effects of gabapentinoids on opioid consumption and postoperative pulmonary complications following total hip or knee arthroplasty (THA or TKA). We hypothesized that use of a gabapentinoid on the day of THA or TKA is associated with an increased risk of postoperative pulmonary complications in a dose-response fashion compared with the risk for patients who did not receive the drug. METHODS: Using the Premier Database, we identified adults who underwent elective primary THA or TKA from 2009 to 2014. The exposure was receipt of a gabapentinoid (gabapentin or pregabalin) on the day of surgery. Gabapentin dose was categorized into 5 groups: none, 1 to 350, 351 to 700, 701 to 1,050, and >1,050 mg per day. Pregabalin dose was categorized into 4 groups: none, 1 to 110, 111 to 250, and >250 mg per day. The primary outcome was a composite of postoperative pulmonary complications, defined as respiratory failure, pneumonia, reintubation, pulmonary edema, noninvasive ventilation, or invasive mechanical ventilation. RESULTS: Of 858,306 patients who underwent THA or TKA, 11.0% received gabapentin and 10.2% received pregabalin. The mean age (and standard deviation) of the patients was 65.6 ± 10.7 years, 39.6% were male, 78.2% were Caucasian, and 55.2% were covered by Medicare. In multilevel regression analysis, receipt of gabapentinoid at any dose on the day of surgery was associated with increased odds of postoperative pulmonary complications. Compared with no exposure to the drug being used by the particular group, all dose ranges of gabapentin and pregabalin were associated with greater odds of postoperative pulmonary complications (odds ratio, 95% confidence interval = 1.51, 1.40 to 1.63, for >1,050 mg of gabapentin and 1.81, 1.57 to 2.09, for >250 mg of pregabalin). We found no clinically meaningful associations between exposure to either gabapentin or pregabalin and perioperative opioid consumption or the length of the hospital stay. CONCLUSIONS: Exposure to gabapentinoids at any dose on the day of THA or TKA was associated with increased odds of postoperative pulmonary complications in a dose-response fashion, with minimal effects on perioperative opioid consumption. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Focused cardiac ultrasound in preoperative assessment: the perioperative provider's new stethoscope?

Focused cardiac ultrasound (FoCUS)-a simplified, qualitative version of echocardiography-is a well-established tool in the armamentarium of critical care and emergency medicine. This review explores the extent to which FoCUS could also be used to enhance the preoperative physical examination to better utilise resources and identify those who would benefit most from detailed echocardiography prior to surgery. Among the range of pathologies that FoCUS can screen for, the conditions it provides the most utility in the preoperative setting are left ventricular systolic dysfunction (LVSD) and, in certain circumstances, significant aortic stenosis (AS). Thus, FoCUS could help answer two common preoperative diagnostic questions. First, in a patient with high cardiovascular risk who subjectively reports a good functional status, is there evidence of LVSD? Second, does an asymptomatic patient with a systolic murmur have significant aortic stenosis? Importantly, many cardiac pathologies of relevance to perioperative care fall outside the scope of FoCUS, including regional wall motion abnormalities, diastolic dysfunction, left ventricular outflow obstruction, and pulmonary hypertension. Current evidence suggests that after structured training in FoCUS and performance of 20-30 supervised examinations, clinicians can achieve competence in basic cardiac ultrasound image acquisition. However, it is not known precisely how many training exams are necessary to achieve competence in FoCUS image interpretation. Given the short history of FoCUS use in preoperative evaluation, further research is needed to determine what additional questions FoCUS is suited to answer in the pre-operative setting.

Impact of an enhanced recovery pathway on length of stay and complications in elective radical cystectomy: a before and after cohort study.

BACKGROUND: Enhanced recovery after surgery (ERAS) pathways aim to standardize and integrate perioperative care, incorporating the best available evidence-based practice throughout the perioperative period targeted at attenuating the surgical stress response while optimizing physiologic function, with the goal of facilitating recovery. Radical cystectomy is associated with significant postoperative morbidity, but comprehensive ERAS pathways have not been well studied in this population. METHODS: This is a before and after cohort study of an ERAS pathway for radical cystectomy at a large academic medical center. Following introduction of the ERAS pathway and a wash in period, we prospectively collected data from the next 100 consecutive subjects undergoing radical cystectomy with the ERAS pathway. This cohort was compared to a retrospective cohort of 100 consecutive patients undergoing radical cystectomy with traditional care. The primary outcome was hospital length of stay. Secondary outcomes included perioperative management, time to recovery milestones, complications, and costs. RESULTS: Implementation of an ERAS pathway for radical cystectomy was associated with reduced hospital length of stay (median LOS 10 days (IQR = 8-18) vs 7 days (IQR = 6-11); p < 0.0001), reduced time to key recovery milestones, including days to first stool (5.83 vs 3.99; p < 0.001) and days to first solid food (9.68 vs 3.2; p < 0.001), reductions in some complications, and a 26.6% reduction in overall costs (p < 0.001). CONCLUSIONS: Our data support the use of an ERAS pathway for radical cystectomy and add to the increasing body of literature supporting enhanced recovery over a wide variety of procedures. TRIAL REGISTRATION: Not applicable.

Surgical Prehabilitation: Nutrition and Exercise.

Complications after major surgery account for a disproportionate amount of in-hospital morbidity and mortality. Recent efforts have focused on preoperative optimization in an attempt to modify the risk associated with major surgery. Underaddressed, but important, modifiable risk factors are physical fitness and nutritional status. Surgical patients are particularly at risk of 3 related, but distinct, conditions: frailty, sarcopenia, and reduced physical fitness. Exercise-based prehabilitation strategies have shown promise in terms of improving aerobic fitness, although their impact on key clinical perioperative outcome measures have not been fully determined. Preoperative nutritional status also has a strong bearing on perioperative outcome.

Molecular Mechanisms Linking Autonomic Dysfunction and Impaired Cardiac Contractility in Critical Illness.

OBJECTIVES: Molecular mechanisms linking autonomic dysfunction with poorer clinical outcomes in critical illness remain unclear. We hypothesized that baroreflex dysfunction alone is sufficient to cause cardiac impairment through neurohormonal activation of (nicotinamide adenine dinucleotide phosphate oxidase dependent) oxidative stress resulting in increased expression of G-protein-coupled receptor kinase 2, a key negative regulator of cardiac function. DESIGN: Laboratory/clinical investigations. SETTING: University laboratory/medical centers. SUBJECTS: Adult rats; wild-type/nicotinamide adenine dinucleotide phosphate oxidase subunit-2-deficient mice; elective surgical patients. INTERVENTIONS: Cardiac performance was assessed by transthoracic echocardiography following experimental baroreflex dysfunction (sino-aortic denervation) in rats and mice. Immunoblots assessed G-protein-coupled receptor recycling proteins expression in rodent cardiomyocytes and patient mononuclear leukocytes. In surgical patients, heart rate recovery after cardiopulmonary exercise testing, time/frequency measures of parasympathetic variables were related to the presence/absence of baroreflex dysfunction (defined by spontaneous baroreflex sensitivity of <6 ms mm Hg). The associations of baroreflex dysfunction with intraoperative cardiac function and outcomes were assessed. MEASUREMENTS AND MAIN RESULTS: Experimental baroreflex dysfunction in rats and mice resulted in impaired cardiac contractility and upregulation of G-protein-coupled receptor kinase 2 expression. In mice, genetic deficiency of gp91 nicotinamide adenine dinucleotide phosphate oxidase subunit-2 prevented upregulation of G-protein-coupled receptor kinase 2 expression in conditions of baroreflex dysfunction and preserved cardiac function. Baroreflex dysfunction was present in 81 of 249 patients (32.5%) and was characterized by lower parasympathetic tone and increased G-protein-coupled receptor kinase 2 expression in mononuclear leukocytes. Baroreflex dysfunction in patients was also associated with impaired intraoperative cardiac contractility. Critical illness and mortality were more frequent in surgical patients with baroreflex dysfunction (relative risk, 1.66 [95% CI, 1.16-2.39]; p = 0.006). CONCLUSIONS: Reduced baroreflex sensitivity is associated with nicotinamide adenine dinucleotide phosphate oxidase subunit-2-mediated upregulation of G-protein-coupled receptor kinase 2 expression in cardiomyocytes and impaired cardiac contractility. Autonomic dysfunction predisposes patients to the development of critical illness and increases mortality.

Individualised oxygen delivery targeted haemodynamic therapy in high-risk surgical patients: a multicentre, randomised, double-blind, controlled, mechanistic trial.

BACKGROUND: Morbidity after major surgery is associated with low oxygen delivery. Haemodynamic therapy aimed at increasing oxygen delivery in an effort to reduce oxygen debt, tissue injury, and morbidity, is controversial. The most appropriate target for this strategy is unclear and might have several off-target effects, including loss of neural (parasympathetic)-mediated cellular protection. We hypothesised that individualised oxygen delivery targeted haemodynamic therapy (goal-directed therapy) in high-risk surgical patients would reduce postoperative morbidity, while secondarily addressing whether goal-directed therapy affected parasympathetic function. METHODS: In this multicentre, randomised, double-blind, controlled trial, adult patients undergoing major elective surgery were allocated by computer-generated randomisation to a postoperative protocol (fluid, with and without dobutamine) targeted to achieve their individual preoperative oxygen delivery value (goal-directed therapy) or standardised care (control). Patients and staff were masked to the intervention. The primary outcome was absolute risk reduction (ARR) in morbidity (defined by Clavien-Dindo grade II or more) on postoperative day 2. We also assessed a secondary outcome focused on parasympathetic function, using time-domain heart rate variability measures. Analyses were done on an intention-to-treat basis. The trial was registered with Controlled Clinical Trials (number ISRCTN76894700). FINDINGS: We enrolled 204 patients between May 20, 2010, and Feb 12, 2014. Intention-to-treat analysis of the 187 (92%) patients who completed the trial intervention period showed that early morbidity was similar between goal-directed therapy (44 [46%] of 95 patients) and control groups (49 [53%] of 92 patients) (ARR -7%, 95% CI -22 to 7; p=0·30). Prespecified secondary analysis showed that 123 (66%) of 187 patients achieved preoperative oxygen delivery (irrespective of intervention). These patients sustained less morbidity (ARR 19%, 95% CI 3-34; p=0·016), including less infectious complications. Goal-directed therapy reduced parasympathetic activity postoperatively (relative risk 1·33, 95% CI 1·01-1·74). INTERPRETATION: Achievement of preoperative oxygen delivery values in the postoperative phase was associated with less morbidity, but this was not affected by the use of an oxygen delivery targeted strategy. Reduced parasympathetic activity after goal-directed therapy was associated with the failure of this intervention to reduce postoperative morbidity. FUNDING: Academy of Medical Sciences and Health Foundation Clinician Scientist Award.

A confirmed Ehrlichia ewingii infection likely acquired through platelet transfusion.

Ehrlichiosis is a tick-borne disease that ranges in severity from asymptomatic infection to fatal sepsis. Ehrlichiosis acquired from transfusion of blood products has not been documented in the literature to date. A case of Ehrlichia ewingii infection likely transmitted by transfusion of leukoreduced platelets is described, and public health implications are discussed.

Biomarkers to guide perioperative management.

Stratifying preoperative risk and guiding perioperative therapy objectively has acquired critical importance, given robust data demonstrating that morbidity following non-cardiac surgery confers substantially increased risk of death, even beyond hospital discharge. The development of useful perioperative biomarkers depends fundamentally on both prospective morbidity data that enable the identification of higher risk patients as well as the translational understanding of pathophysiological mechanisms underlying postoperative organ dysfunction, the development of which may be specific to the perioperative environment. The emergence of cardiac insufficiency, rather than cardiac ischaemia, as the dominant factor associated with excess risk of prolonged postoperative morbidity has promoted the application of biomarkers used commonly in cardiovascular medicine. Several novel, organ specific biomarkers offer potential perioperative application. Nevertheless, common tests/biomarkers that are widely available do provide valuable, objective information that is perhaps under-utilised perioperatively. Despite significant challenges, perioperative medicine presents exciting-arguably unique-opportunities for novel biomarker development.