Choice of anesthesia technique is associated with earlier hospital discharge and reduced costs after transcatheter transfemoral aortic valve implantation.

Background: Transcatheter aortic valve implantation (TAVI) has become a viable alternative to palliation in patients with severe aortic stenosis. We compared general anesthesia to conscious sedation for TAVI procedures with respect to post operative morbidity, hospital length of stay, and financial burden. Methods: We conducted a retrospective review of prospectively collected data in patients undergoing transfemoral TAVI procedures from 2012 to 2017. Patients were matched based on age and sex and classed into either general anesthesia or conscious sedation groups respectively. Conscious sedation was provided with a dexmedetomidine infusion, and patients in general anesthesia group received a standard induction, tracheal intubation, and maintenance with sevoflurane. The hospital case costs were compared between the two groups before and after adjustment for inflation. Results: We matched 124 pairs for a total of 248 patients. Both groups were similar with respect to demographic data, past medical history, medications, and intraoperative characteristics. There was no difference in postoperative morbidity and mortality between the two groups. The median hospital length of stay was 5 [interquartile range (IQR): 3, 10] and 7 (IQR: 4, 12) days, P=0.01, and after adjustment for inflation, the total hospital case costs were $48,984 (IQR: $44,802, $61,438) Canadian (CAD) vs. $55,333 (IQR: $46,832, $68,702) CAD, P=0.01, in the conscious sedation and general anesthesia groups, respectively. Conclusions: Advancements in TAVI technologies, conscious sedation and a collaborative, multidisciplinary team approach reduces overall length of hospital stay and procedure costs.

Predicting Early Extubation After Liver Transplantation: External Validation and Improved Generalizability of a Proposed Fast-track Score.

BACKGROUND: Early extubation of liver transplantation recipients is a cornerstone of fast-track (FT) pathways. Identifying suitable candidates has previously been accomplished using perioperative variables to develop a FT probability score. The objective of this study was to externally validate a proposed FT score. METHODS: Following Research Ethics Board approval, data were extracted on liver transplants conducted at a single center from 2009 to 2017. Data extracted included patient characteristics, intraoperative variables, and postoperative outcome variables. The proposed FT score utilized 9 variables: age, gender, body mass index, model of end-stage liver disease, retransplant, preoperative hospital admission, blood transfusion, operative time, and vasopressor use. We calculated the FT score in our cohort, and assessed the discrimination and calibration of the model. Score performance was explored by subgroup analyses, customization and altering the outcome definition. RESULTS: The FT score was found to predict higher rates of successful FT than was observed in the external cohort (n = 1385) and had reduced discrimination (area under the receiver operating curve, 0.711; 95% confidence interval, 0.682-0.741) compared with the original internal validation cohort (area under the receiver operating curve, 0.830; 95% confidence interval, 0.789-0.871; P < 0.0001). Discrimination was improved by customizing the transfusion (P < 0.0001) components of the simplified score or by level 1 customization of all regression model coefficients (P < 0.0001). A time-based definition of FT (early extubation) did not alter the accuracy of the prediction score (P = 0.914), improving the model's generalizability. CONCLUSIONS: The proposed FT score may help identify patients suitable for early extubation and FT pathways after liver transplantation in conjunction with clinical judgment.

Cardiologists' and nephrologists' management of atrial fibrillation in hemodialysis patients
.

BACKGROUND: Antithrombotic therapy for stroke prevention in atrial fibrillation (AF) is considered a standard of care, but for hemodialysis (HD) patients the benefits are unclear, and bleeding risks are high. Our study objective was to compare cardiologists' and nephrologists' stroke prevention practices in different patient risk scenarios. MATERIALS AND METHODS: A cross-sectional, online survey was distributed to members of three Canadian physician societies (Nephrology, Cardiovascular, Heart Rhythm), and to cardiologists affiliated with three Canadian Universities. The questionnaire included four AF scenarios in HD patients with varying stroke and bleeding risks. Physicians selected one of six antithrombotic therapy options for each scenario. RESULTS: Cardiologists were 3 times more likely than nephro-logists to choose anticoagulant therapy over both antiplatelet and no drug therapy, regardless of stroke or bleeding risk (p < 0.001). Physicians' drug therapy choices in regards to level of stroke and bleeding risk reflected the expected pattern based on current evidence. CONCLUSION: Cardiologists were more likely to prescribe anticoagulant therapy for AF in the HD population compared to nephrologists, regardless of patient stroke or bleeding risk.

Utilization and Effectiveness of Desmopressin Acetate After Cardiac Surgery Supplemented With Point-of-Care Hemostatic Testing: A Propensity-Score-Matched Analysis.

OBJECTIVES: To explore the utilization pattern and hemostatic effectiveness of desmopressin acetate (DDAVP) supplemented with point-of-care (POC) hemostatic testing in contemporary cardiac surgery. DESIGN: Retrospective, observational study. SETTING: Single quaternary care university hospital. PARTICIPANTS: The study comprised 2,468 consecutive patients undergoing cardiac surgery-1,237 before and 1,231 after the introduction of POC testing. INTERVENTIONS: The incidence of DDAVP administration during the year before (2012) and after (2013) the initiation of POC-based viscoelastic (ROTEM; Tem International GmBH, Munich, Germany) and platelet function (Plateletworks; Helena Laboratories, Beaumont, TX) testing was determined. Propensity-score matching was used to examine the association between DDAVP administration and major bleeding during each time period. MEASUREMENTS AND MAIN RESULTS: DDAVP was administered more than twice as often after POC implementation (41% v 20%, p<0.001). Major bleeding was defined based on the universal definition of perioperative bleeding in adult cardiac surgery. Propensity matching identified 224 well-balanced pairs of DDAVP recipients and control patients before and 298 such pairs after the implementation of POC testing. After adjusting for matched data, DDAVP administration was associated with 1.70 (95% confidence interval 1.25-2.32, p<0.001) and 1.51 (95% confidence interval 1.15-1.98, p = 0.003) increases in the odds of major bleeding before and after the initiation of POC testing, respectively. CONCLUSIONS: Clinicians should be cognizant of the potential for increased use of DDAVP despite limited evidence of benefit in contemporary cardiac anesthesia practice supplemented with POC-based hemostatic testing.

Serial post-surgical stimulated and unstimulated highly sensitive thyroglobulin measurements in low- and intermediate-risk papillary thyroid carcinoma patients not receiving radioactive iodine.

The purpose of this study was to determine the natural temporal trends of serial thyroglobulin (Tg) among low/intermediate-risk PTC patients not receiving radioactive iodine (RAI) using TSH-stimulated Tg (Stim-Tg) and unstimulated highly sensitive Tg (u-hsTg). We prospectively analyzed serial Stim-Tg measurements after total thyroidectomy ± therapeutic central neck dissection among 121 consecutive low/intermediate-risk PTC patients who did not receive RAI, of whom 104 also had serial u-hsTg measurements available. Median follow-up was 6.5 years with Stim-Tg measurements commencing 3 months after surgery and u-hsTg commencing 1.8 years after surgery (when the assay became available). TSH stimulation was performed with 9-day T3 withdrawal, 22-day T4 withdrawal, or using recombinant human TSH (rhTSH). To account for within-patient correlations of repeated Tg measurements, temporal trends in Stim-Tg and u-hsTg were assessed using Generalized Estimating Equations. Stim-Tg models were adjusted for the method of TSH stimulation, whereas the u-hsTg models were adjusted for concurrent TSH level. Linear regression modeling was used to assess the trend in serial Stim-Tg and u-hsTg measurements as a function time from time of surgery throughout the duration of follow-up. The main outcome measured was the change in u-hsTg and Stim-Tg measurements over time. A total of 337 Stim-Tg (2.8/patient) and 602 u-hsTg (5.8/patient) measurements were analyzed. Among the 337 Stim-Tg measurements, Stim-Tg was assessed using rhTSH in 202 (60 %), T4 withdrawal in 41 (12 %), and T3 withdrawal in 94 (28 %) measurements. The overall mean ± 1SD for Stim-Tg and u-hsTg measured was 1.0 ± 1.2 and 0.2 ± 0.1 µg/L, respectively. When adjusted for method of TSH stimulation, serial Stim-Tg measurements did not significantly change over time (all p = NS). The estimated changes in Stim-Tg per year for rhTSH, T4 withdrawal, and T3 withdrawal were 0.01, -0.08, and 0.04 µg/L, respectively. Upon exclusion of 73 patients with an initial undetectable Stim-Tg (n = 48), serial Stim-Tg measurements did not change significantly over time (all p = NS). For these patients, the estimated changes in Stim-Tg per year for rhTSH, T4 withdrawal, and T3 withdrawal were -0.09, -0.10, and 0.01 µg/L, respectively. Serial u-hsTg measurements did not significantly change over time after adjusting for TSH level (p = NS). The estimated change in u-hsTg per year was -0.003 µg/L. No patients had any clinical or imaging evidence of a recurrence during the duration of their follow-up. Among low/intermediate-risk PTC patients not treated with RAI, serial post-surgical Stim-Tg and u-hsTg measurements do not change significantly over a median follow-up of 6.5 years.

What epidural opioid results in the best analgesia outcomes and fewest side effects after surgery?: a meta-analysis of randomized controlled trials.

BACKGROUND: Epidural opioids are widely used for central neuraxial blockade and postoperative analgesia. However, differences in analgesic efficacy and side effect rates among individual opioids remain controversial. METHODS: We conducted a random-effects meta-analysis of randomized controlled trials that compared at least 2 continuous epidural infusions for acute postoperative analgesia over at least 24 hours. Individual study data were weighted by the inverse-variance method. Visual analog scale (VAS) pain scores were the primary outcome. Secondary outcomes included opioid side effects, such as pruritus, postoperative nausea and vomiting (PONV), sedation, hypotension, and respiratory depression. RESULTS: Nineteen of the 24 trials included compared 2 of the following opioids: morphine, fentanyl, or sufentanil. The total subjects studied were 1513. Pooled analysis by type of surgery showed no clinically significant differences in VAS pain scores at any time after surgery. There were more PONV (OR = 1.91; 95% CI, 1.14-3.18; P = 0.014) and perhaps pruritus (OR = 1.64; 95% CI, 0.98-2.76; P = 0.162) with morphine compared to fentanyl. Total opioid consumption differed only in the trials comparing morphine and fentanyl, where patients in the morphine group required 1.2 mg (of morphine equivalent) less (95% CI, 0.27-2.18). Use of analgesic adjuncts was similar for all but 2 studies. CONCLUSIONS: Analgesic outcome, in terms of VAS pain score, was similar between the epidural opioids studied. These similarities in analgesia may reflect the common practices of concurrently using epidural local anesthetics with the opioids and titrating infusion rates according to a patient's pain status. With respect to side effects, the incidence of PONV and possibly pruritus was higher with morphine compared with fentanyl, despite there being similar total opioid consumption between those groups.

Platelet dysfunction as measured by a point-of-care monitor is an independent predictor of high blood loss in cardiac surgery.

BACKGROUND: Excessive bleeding carries a heavy burden of illness in cardiac surgery. Although platelet dysfunction is considered to be an important cause, it is not routinely measured. Our objective was to explore the relationship between platelet dysfunction and blood loss in cardiac surgery. METHODS: In 100 consenting patients undergoing cardiac surgery requiring cardiopulmonary bypass, platelet function was measured before, during, and after bypass with a point-of-care device that compares platelet counts before and after exposure to an agonist. Clinicians were blinded to the results of testing. Patients whose calculated blood loss was part of the highest quartile for the cohort were classified as having had high blood loss. The independent relationship between platelet function and high blood loss was measured with the aid of multivariable Poisson regression modeling (with a robust error variance) that controlled for patients' overall risk of high blood loss. RESULTS: Calculated blood loss was negatively skewed with a median of 798 mL (25th and 75th percentiles of 380 and 1775 mL). Patients whose blood loss exceeded 1770 mL were classified as having had high blood loss, and 25 patients met this criterion. There was 1 death in the high blood loss group unrelated to hemorrhage. After adjusting for bleeding risk, each 10 × 10/L increase in collagen-activated functional platelet count during rewarming and postprotamine, respectively, was associated with a relative risk of 0.89 (95% confidence interval, 0.82-0.97; P = 0.006) and 0.87 (95% confidence interval, 0.78-0.98; P = 0.02) for high blood loss. CONCLUSIONS: Platelet dysfunction, as measured by a point-of-care method during rewarming and postprotamine, is independently associated with high blood loss in cardiac surgery. Additional studies are needed to determine whether the incorporation of this assay into blood management algorithms might help rationalize blood transfusion therapy, potentially reducing blood loss and improving clinical outcomes.

Cardiorespiratory complications of neuraxial opioids in patients with obstructive sleep apnea: a systematic review.

We sought to determine the rate of cardiorespiratory complications following neuraxial opioid administration in the setting of obstructive sleep apnea (OSA). This systematic review of the leading biomedical databases originated from a university-affiliated, tertiary-care teaching hospital. A systematic search of Medline, Embase, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and the International Pharmaceutical Abstracts Database (1970 - September 2011) was undertaken. Cardiorespiratory complications were stratified into minor and major based on existing OSA literature. Five studies, including a total of 121 patients, were selected for analysis. All studies comprised low-quality evidence. Six major cardiorespiratory complications were reported among 5 (4.1%) patients and included three deaths, one cardiorespiratory arrest, and two episodes of severe respiratory depression. Five of these complications occurred during continuous fentanyl-containing epidural infusions and without concurrent positive airway pressure treatment. The rate of cardiorespiratory complications following the administration of neuraxial opioids to surgical patients with OSA is difficult to determine.

Analysis of histomorphology in malignant hyperthermia-susceptible patients.

BACKGROUND: Malignant hyperthermia (MH) is a potentially lethal disorder of skeletal muscle triggered by anesthetic agents. A histomorphological examination of diseased muscle may provide insight into MH pathophysiology, but it is not a routine part of standard-of-care practice for the identification of MH-susceptibility. In this study, we investigated muscle histomorphology in a large cohort of MH-susceptible (MHS) patients and examined its relationship to genotype and phenotype. METHODS: All consenting patients who were identified as MHS based on a caffeine-halothane contracture test (CHCT) performed during 1992-2011 were retrospectively identified and recruited for this study. Results of the histomorphological examination, which is a routine part of our centre-specific practice, were reviewed. Patient demographics, MH proband status, histological features, CHCTs, and genetic results for MH-causative mutations were summarized. RESULTS: Seven of the 399 patients classified as MHS had histological characteristics consistent with central core disease, and one patient was a carrier of Duchenne's muscular dystrophy. Eighty-six (22%) patients had histological abnormalities, and five (6%) of these had evidence of "frank" myopathy. No histologic abnormalities were consistent among the MHS patients; however, a higher proportion of MH probands had abnormal histomorphology compared with the general MHS population, and patients with evidence of "frank" myopathy showed similarities in clinical history, biochemistry, CHCT, and genetic testing. CONCLUSION: Despite the inability of the histomorphological examination to identify consistent features in MHS patients, histology may serve as a potential adjunct to CHCT and aid in the identification of other myopathies. Nevertheless, the specifics of its utility ought to be assessed in other studies and by way of formal cost-effectiveness analysis.

Predictive value of metastatic cervical lymph node ratio in papillary thyroid carcinoma recurrence.

BACKGROUND: The purpose of this study was to determine whether the proportion of metastatic cervical lymph nodes resected (metastatic lymph node ratio [MLNR]) predicted papillary thyroid carcinoma (PTC) recurrence, and whether MLNR could alter the predictive ability of TNM nodal classification for recurrence in PTC. METHODS: We conducted a retrospective review of patients with PTC who underwent a total or near-total thyroidectomy with at least 1 lymph node removed at our institution. RESULTS: Of 253 patients, 35 (13.8%) developed recurrent disease. The total MLNR (ratio between total metastatic lymph nodes and total number of lymph nodes resected) independently predicted PTC recurrence (odds ratio [OR], 1.024; 95% confidence interval [CI], 1.010-1.039; p = .001). In receiver operating characteristic (ROC) curve analysis, TNM nodal classification with total MLNR had greater accuracy in predicting PTC recurrence than did TNM nodal classification alone (0.726 and 0.675, respectively). CONCLUSION: MLNR is an independent predictor of PTC recurrence and enhances the predictive value of TNM nodal classification.

The clinical utility of an index of global oxygenation for guiding red blood cell transfusion in cardiac surgery.

BACKGROUND: This observational study explored the potential utility of oxygen extraction ratio (O2ER) as an adjunct to the hemoglobin (Hb) concentration for guiding red blood cell (RBC) transfusion decisions after cardiac surgery with cardiopulmonary bypass (CPB). STUDY DESIGN AND METHODS: Hb and O2ER measures were obtained before as well as 15 and 120 minutes after RBC transfusion episodes (defined as 1-2 RBC units given in succession after CPB, within 24 hr. of surgery). Changes related to RBC transfusions among patients with normal (30%) and elevated(>30%) pretransfusion O2ERs were analyzed. RESULTS: Of the 176 patients enrolled, 74 received RBC transfusions. Of these, 50 had data available for 62 transfusion episodes. Pretransfusion episode O2ER values were elevated in 27 cases and normal in 35(56%) cases. Among those who received transfusion for low Hb concentration, 43 percent (27/62) had normal pretransfusion O2ER values. While the posttransfusion O2ER values did not change in patients with normal pretransfusion O2ER values, they did decrease inpatients with elevated pretransfusion O2ER values (% change [+/-SD] at 15 and 120 min after transfusion was -5.2 +/- 7.8 and -3.8 +/- 8.0%, respectively; p < 0.05). CONCLUSION: If a normal O2ER in anemic patients with no evidence of organ dysfunction indicates adequate tissue oxygen delivery, then our findings suggest that incorporating O2ER into the transfusion decision will substantially reduce post-cardiac surgery RBC transfusions by allowing us to safely avoid transfusing this group of patients. Future studies are needed to assess the validity of this conclusion.

Influence of age and primary tumor size on the risk for residual/recurrent well-differentiated thyroid carcinoma.

BACKGROUND: Though age and primary tumor size predict cancer-specific survival in well-differentiated thyroid carcinoma (WDTC), their influence on residual/recurrent disease has not been elucidated. METHODS: In a retrospective study, residual/recurrent disease was defined by the surrogate outcome of positive (>or=2 microg/L) follow-up stimulated thyroglobulin after surgery and radioactive remnant ablation. Age, primary tumor size, and clinical staging systems were examined in the context of stimulated thyroglobulin outcome. RESULTS: A total of 246 patients were followed up for a mean of 5.8 years. No significant difference in age (t(239) = 0.61, p > .05) or tumor size (t(237) = 0.16, p > .05) was found among patients with positive follow-up stimulated thyroglobulin compared with those with negative results. pTNM staging failed to demonstrate significant, stage-dependent increase in the percentage of patients with positive stimulated thyroglobulin, chi(2)(2, N = 229) = 0.17, p > .05, unlike staging based solely on surgical pathology, chi(2)(2, N = 241) = 34.97, p < .001. CONCLUSION: Age, primary tumor size, and pTNM staging do not predict risk for residual/recurrent WDTC, whereas extrathyroidal extension at initial surgery is predictive.