Pathological findings associated with the updated European Society of Cardiology 2022 guidelines for preoperative cardiac testing: an observational cohort modelling study

BACKGROUND

In 2022, the European Society of Cardiology updated guidelines for preoperative evaluation. The aims of this study were to quantify: (1) the impact of the updated recommendations on the yield of pathological findings compared with the previous guidelines published in 2014; (2) the impact of preoperative B-type natriuretic peptide (NT-proBNP) use for risk estimation on the yield of pathological findings; and (3) the association between 2022 guideline adherence and outcomes.

METHODS

This was a secondary analysis of MET-REPAIR, an international, prospective observational cohort study (NCT03016936). Primary endpoints were reduced ejection fraction (EF<40%), stress-induced ischaemia, and major adverse cardiovascular events (MACE). The explanatory variables were class of recommendations for transthoracic echocardiography (TTE), stress imaging, and guideline adherence. We conducted second-order Monte Carlo simulations and multivariable regression.

RESULTS

In total, 15,529 patients (39% female, median age 72 [inter-quartile range: 67-78] yr) were included. The 2022 update changed the recommendation for preoperative TTE in 39.7% patients, and for preoperative stress imaging in 12.9% patients. The update resulted in missing 1 EF <40% every 3 fewer conducted TTE, and in 4 additional stress imaging per 1 additionally detected ischaemia events. For cardiac stress testing, four more investigations were performed for every 1 additionally detected ischaemia episodes. Use of NT-proBNP did not improve the yield of pathological findings. Multivariable regression analysis failed to find an association between adherence to the updated guidelines and MACE.

CONCLUSIONS

The 2022 update for preoperative cardiac testing resulted in a relevant increase in tests receiving a stronger recommendation. The updated recommendations for TTE did not improve the yield of pathological cardiac testing.

Perioperative copeptin: predictive value and risk stratification in patients undergoing major noncardiac surgery-a prospective observational cohort study

PURPOSE

Biomarkers can aid in perioperative risk stratification. While preoperative copeptin has been associated with adverse events, intraoperative information is lacking and this association may rather reflect a baseline risk. Knowledge about correlations between postoperative copeptin measurements and clinically relevant outcomes is scarce. We examined the association of perioperative copeptin concentrations with postoperative all-cause mortality and/or major adverse cardiac and cerebrovascular events (MACCE) at 12 months and 30 days as well as with perioperative myocardial injury (PMI).

METHODS

We conducted a prospective observational cohort study of adults undergoing noncardiac surgery with intermediate to high surgical risk in Basel, Switzerland, and Düsseldorf, Germany from February 2016 to December 2020. We measured copeptin and cardiac troponin before surgery, immediately after surgery (0 hr) and once between the second and fourth postoperative day (POD 2-4).

RESULTS

A primary outcome event of a composite of all-cause mortality and/or MACCE at 12 months occurred in 48/502 patients (9.6%). Elevated preoperative copeptin (> 14 pmol·L-1), immediate postoperative copeptin (> 90 pmol·L-1), and copeptin on POD 2-4 (> 14 pmol·L-1) were associated with lower one-year MACCE-free and/or mortality-free survival (hazard ratio [HR], 2.89; 95% confidence interval [CI], 1.62 to 5.2; HR, 2.07; 95% CI, 1.17 to 3.66; and HR, 2.47; 95% CI, 1.36 to 4.46, respectively). Multivariable analysis continued to show an association for preoperative and postoperative copeptin on POD 2-4. Furthermore, elevated copeptin on POD 2-4 showed an association with 30-day MACCE-free survival (HR, 2.15; 95% CI, 1.18 to 3.91). A total of 64 of 489 patients showed PMI (13.1%). Elevated preoperative copeptin was not associated with PMI, while immediate postoperative copeptin was modestly associated with PMI.

CONCLUSION

The results of the present prospective observational cohort study suggest that perioperative copeptin concentrations can help identify patients at risk for all-cause mortality and/or MACCE. Other identified risk factors were revised cardiac risk index, body mass index, surgical risk, and preoperative hemoglobin.

TRIAL REGISTRATION

ClinicalTrials.gov (NCT02687776); first submitted 9 February 2016.

Pressure-Volume Loops for Reviewing Right Ventricular Physiology and Failure in the Context of Left Ventricular Assist Device Implantation

Right ventricular (RV) function is complex as a number of determinants beyond preload, inotropy and afterload play a fundamental role. In particular, arterial elastance (Ea), ventriculo-arterial coupling (VAC), and (systolic) ventricular interdependence play a vital role for the right ventricle. Understanding and actively visualizing these interactions in the failing RV as well as in the altered hemodynamic and morphological situation of left ventricular assist device (LVAD) implantation may aid clinicians in their understanding of RV dysfunction and failure. While, admittedly, hard data is scarce and invasive pressure-volume loop measurements will not become routine in cardiac surgery, we hope that clinicians will benefit from the comprehensive, simulation-based review of RV pathology. In particular, the aim of this article is to first, address and clarify the pathophysiologic hemodynamic factors that lead to RV dysfunction and then, second, expand upon this basis examining the changes occurring by LVAD implantation. This is illustrated using Harvi software which shows elastance, ventricular arterial coupling, and ventricular interdependence by simultaneously showing pressure volume loops of the right and left ventricle.

NT-proBNP or Self-Reported Functional Capacity in Estimating Risk of Cardiovascular Events After Noncardiac Surgery

Importance

Nearly 16 million surgical procedures are conducted in North America yearly, and postoperative cardiovascular events are frequent. Guidelines suggest functional capacity or B-type natriuretic peptides (BNP) to guide perioperative management. Data comparing the performance of these approaches are scarce.

Objective

To compare the addition of either N-terminal pro-BNP (NT-proBNP) or self-reported functional capacity to clinical scores to estimate the risk of major adverse cardiac events (MACE).

Design, Setting, and Participants

This cohort study included patients undergoing inpatient, elective, noncardiac surgery at 25 tertiary care hospitals in Europe between June 2017 and April 2020. Analysis was conducted in January 2023. Eligible patients were either aged 45 years or older with a Revised Cardiac Risk Index (RCRI) of 2 or higher or a National Surgical Quality Improvement Program, Risk Calculator for Myocardial Infarction and Cardiac (NSQIP MICA) above 1%, or they were aged 65 years or older and underwent intermediate or high-risk procedures.

Exposures

Preoperative NT-proBNP and the following self-reported measures of functional capacity were the exposures: (1) questionnaire-estimated metabolic equivalents (METs), (2) ability to climb 1 floor, and (3) level of regular physical activity.

Main Outcome and Measures

MACE was defined as a composite end point of in-hospital cardiovascular mortality, cardiac arrest, myocardial infarction, stroke, and congestive heart failure requiring transfer to a higher unit of care.

Results

A total of 3731 eligible patients undergoing noncardiac surgery were analyzed; 3597 patients had complete data (1258 women [35.0%]; 1463 (40.7%) aged 75 years or older; 86 [2.4%] experienced a MACE). Discrimination of NT-proBNP or functional capacity measures added to clinical scores did not significantly differ (Area under the receiver operating curve: RCRI, age, and 4MET, 0.704; 95% CI, 0.646-0.763; RCRI, age, and 4MET plus floor climbing, 0.702; 95% CI, 0.645-0.760; RCRI, age, and 4MET plus physical activity, 0.724; 95% CI, 0.672-0.775; RCRI, age, and 4MET plus NT-proBNP, 0.736; 95% CI, 0.682-0.790). Benefit analysis favored NT-proBNP at a threshold of 5% or below, ie, if true positives were valued 20 times or more compared with false positives. The findings were similar for NSQIP MICA as baseline clinical scores.

Conclusions and relevance

In this cohort study of nearly 3600 patients with elevated cardiovascular risk undergoing noncardiac surgery, there was no conclusive evidence of a difference between a NT-proBNP-based and a self-reported functional capacity-based estimate of MACE risk.

Trial Registration

ClinicalTrials.gov Identifier: NCT03016936.

Risk assessment for major adverse cardiovascular events after noncardiac surgery using self-reported functional capacity: international prospective cohort study

BACKGROUND

Guidelines endorse self-reported functional capacity for preoperative cardiovascular assessment, although evidence for its predictive value is inconsistent. We hypothesised that self-reported effort tolerance improves prediction of major adverse cardiovascular events (MACEs) after noncardiac surgery.

METHODS

This is an international prospective cohort study (June 2017 to April 2020) in patients undergoing elective noncardiac surgery at elevated cardiovascular risk. Exposures were (i) questionnaire-estimated effort tolerance in metabolic equivalents (METs), (ii) number of floors climbed without resting, (iii) self-perceived cardiopulmonary fitness compared with peers, and (iv) level of regularly performed physical activity. The primary endpoint was in-hospital MACE consisting of cardiovascular mortality, non-fatal cardiac arrest, acute myocardial infarction, stroke, and congestive heart failure requiring transfer to a higher unit of care or resulting in a prolongation of stay on ICU/intermediate care (≥24 h). Mixed-effects logistic regression models were calculated.

RESULTS

In this study, 274 (1.8%) of 15 406 patients experienced MACE. Loss of follow-up was 2%. All self-reported functional capacity measures were independently associated with MACE but did not improve discrimination (area under the curve of receiver operating characteristic [ROC AUC]) over an internal clinical risk model (ROC AUC_baseline 0.74 [0.71-0.77], ROC AUC_{baseline+4METs} 0.74 [0.71-0.77], ROC AUC_{baseline+floors climbed} 0.75 [0.71-0.78], AUC_{baseline+fitnessvspeers} 0.74 [0.71-0.77], and AUC_{baseline+physical activity} 0.75 [0.72-0.78]).

CONCLUSIONS

Assessment of self-reported functional capacity expressed in METs or using the other measures assessed here did not improve prognostic accuracy compared with clinical risk factors. Caution is needed in the use of self-reported functional capacity to guide clinical decisions resulting from risk assessment in patients undergoing noncardiac surgery.

CLINICAL TRIAL REGISTRATION

NCT03016936.

Pain response to cannabidiol in opioid-induced hyperalgesia, acute nociceptive pain, and allodynia using a model mimicking acute pain in healthy adults in a randomized trial (CANAB II)

ABSTRACT

Opioids in general and remifentanil in particular can induce hyperalgesia. Preclinical data suggest that cannabidiol might have the capacity to reduce opioid-induced hyperalgesia (OIH). Thus, we investigated the effect of oral cannabidiol on OIH in healthy volunteers using an established pain model. Twenty-four healthy participants were included in this randomized, double-blinded, crossover study and received either a 1600-mg single-dose oral cannabidiol or placebo. Hyperalgesia, allodynia, and pain were induced by intracutaneous electrical stimulation. To provoke OIH, participants recieved an infusion of 0.1 µg/kg/min remifentanil over a time frame of 30 minutes, starting 100 minutes after oral cannabidiol ingestion. The primary outcome was the area of hyperalgesia (in square centimetres) up to 60 minutes after remifentanil administration. The area of allodynia (in square centimetres) and pain (numeric rating scale) were also assessed.Cannabidiol had no significant effect on hyperalgesia, allodynia, or pain at any time point of measurement compared with placebo. The area of hyperalgesia after remifentanil administration significantly increased compared with baseline (17.0 cm 2 [8.1-28.7] vs 25.3 cm 2 [15.1-39.6]; P = 0.013). Mean cannabidiol blood levels were 4.1 ± 3.0 µg/L (mean ± SD) at 130 minutes after ingestion and were 8.2 μg/L ± 6.9 µg/L (mean ± SD) at 200 minutes. Cannabidiol was well tolerated. We conclude that a high single-oral dose of 1600-mg cannabidiol is not effective in reducing OIH. Before excluding an effect of cannabidiol on OIH, research should focus on drug formulations enabling higher cannabidiol concentrations.

Rotational Thromboelastometry Values After On-Pump Cardiac Surgery - A Retrospective Cohort Study

BACKGROUND

Viscoelastic coagulation monitoring is recommended for coagulation management after cardiac surgery, but optimum target values are poorly defined.

AIMS

To determine "to-be-expected" values in rotational thromboelastometry (ROTEM) after heparin reversal, to correlate ROTEM parameters with fibrinogen levels and platelet count, and to estimate the effect of hemoglobin levels on these measurements.

METHODS

We retrospectively analyzed 571 consecutive adult patients undergoing cardiac surgery with cardiopulmonary bypass from 12/2018 to 08/2020. ROTEM and conventional laboratory measurements were performed 5 to 10 minutes after protamine administration.

RESULTS

Clotting times in EXTEM, INTEM, and FIBTEM were significantly prolonged (72.6%, 96.1%, and 31.8% above reference ranges, respectively). Clot firmness parameters in EXTEM and INTEM were relevantly reduced (7.9% to 14.4% and 9.1% to 32.3% below the reference ranges, respectively). There was an excellent linear correlation of FIBTEM amplitude after 10 min (A10) and of maximal clot firmness (MCF) with fibrinogen concentrations (r = .81 and .80). Areas under receiver operating characteristic (AUROC) for identifying hypofibrinogenemia <1.5 g/L were between .80 and .87. No effect of hematocrit was observed. We also found a linear correlation of EXTEM, INTEM, and EXTEM-FIBTEM at both A10 and MCF with platelet counts (.32 to .68). The AUROCs for identifying thrombocytopenia (<100,000/μL) were .79 to .84, and were greater for A10 than for MCF measurements (P=.074, .001, and <.001, respectively).

CONCLUSIONS

"To-be-expected" ROTEM values after CPB are different from the published reference ranges. ROTEM parameters might allow for reliable estimation of fibrinogen level and platelet count without being influenced by hematocrit.

Analgesic benefit of metamizole and ibuprofen vs. either medication alone: a randomized clinical trial

BACKGROUND

Postoperative pain relief remains a key problem after surgery. Multimodal pain therapy has proven beneficial in alleviating pain to a certain extent. However, when combining non-opioids, the focus has been on NSAIDs and paracetamol, but effects of combined use are only moderate. Metamizole could be a potent adjunct, due to its preclusion in several countries, data on its combined use are sparse, despite its common use in many countries. The aim of this study was to examine whether the combination of metamizole and ibuprofen is superior in relieving postoperative pain to either drug alone.

METHODS

For this randomized, placebo-controlled, cross-over study, 35 patients undergoing bilateral lower third molar extraction were randomized. Each patient received three applications of 1000mg metamizole + 400mg ibuprofen for surgery on one side and either 1000mg metamizole + placebo or 400mg ibuprofen + placebo on the other side. Pain ratings, rescue-medication (tramadol), and sleep were assessed for 18 hours.

RESULTS

The combined treatment of metamizole and ibuprofen showed lower mean pain scores over 12 hours than ibuprofen (2.4±1.3 vs 3.8±1.6; P=0.005)). Further, combined treatment showed lower mean pain scores over 6 hours than ibuprofen (2.0±1.2 vs. 3.1±1.6; P=0.022) or metamizole alone (2.0±1.2 vs. 3.3±1.7; P=0.015). Consumption of rescue medication was lowest in the combination-group (25% vs. 46%-metamizole; 50%-ibuprofen). The trial was stopped prematurely as the COVID-pandemic halted elective surgeries.

CONCLUSIONS

Combined use enables superior pain control compared to ibuprofen after molar extraction and tends to be superior to metamizole alone. The premature study-termination may overestimate this effect.

Pain response to cannabidiol in induced acute nociceptive pain, allodynia, and hyperalgesia by using a model mimicking acute pain in healthy adults in a randomized trial (CANAB I)

ABSTRACT

Preclinical studies have demonstrated the analgesic potential of cannabidiol (CBD). Those suggesting an effect on pain-processing receptors have brought CBD back into focus. This study assessed the effect of CBD on acute pain, hyperalgesia, and allodynia compared with placebo. Twenty healthy volunteers were included in this randomized, placebo-controlled, double-blinded, crossover study assessing pain intensities (using numeric rating scale), secondary hyperalgesia (von Frey filament), and allodynia (dry cotton swab) in a well-established acute pain model with intradermal electrical stimulation. The authors compared the effect of 800-mg orally administered CBD on pain compared with placebo. They further examined the effect on hyperalgesia and allodynia. Cannabidiol whole blood levels were also measured. Pain ratings (mean ± SD) did not differ significantly after CBD application compared with placebo (5.2 ± 0.7 vs 5.3 ± 0.7, P-value 0.928), neither did the areas of hyperalgesia and allodynia differ significantly after CBD application compared with placebo (hyperalgesia 23.9 ± 19.2 cm2 vs 27.4 ± 17.0 cm2, P-value 0.597; allodynia 16.6 ± 13.1 cm2 vs 17.3 ± 14.1 cm2, P-value 0.884). The CBD whole blood level (median, first to third quartile) was 2.0 µg/L (1.5-5.1) 60 minutes and 5.0 µg/L (4.0-10.4) 130 minutes after CBD application. Although the oral application of 800-mg CBD failed to show a significant effect, it is important to focus future research on different dosing, routes of administration, and CBD as a part of multimodal treatment strategies before negating its effects on acute pain.

Assessing Left Ventricular Early Diastolic Velocities With Tissue Doppler and Speckle Tracking by Transesophageal and Transthoracic Echocardiography

BACKGROUND

Assessing diastolic dysfunction is essential and should be part of every routine echocardiography examination. However, clinicians routinely observe lower mitral annular velocities by transesophageal echocardiography (TEE) under anesthesia than described by awake transthoracic echocardiography (TTE). It would be important to know whether this difference persists under constant loading conditions. We hypothesized that mean early diastolic mitral annular velocity, measured by tissue Doppler imaging (TDI, JOURNAL/asag/04.03/00000539-202105000-00029/inline-graphic1/v/2021-04-15T211206Z/r/image-tiff) would be different in the midesophageal 4-chamber (ME 4Ch) than in the apical 4-chamber (AP 4Ch) view under unchanged or constant loading conditions. Secondarily we examined (1) JOURNAL/asag/04.03/00000539-202105000-00029/inline-graphic2/v/2021-04-15T211206Z/r/image-tiff in an alternative transesophageal view with presumed superior Doppler beam alignment, the deep transgastric view (DTG), compared to those in the AP 4Ch, and (2) early diastolic speckle tracking-based strain rate (JOURNAL/asag/04.03/00000539-202105000-00029/inline-graphic3/v/2021-04-15T211206Z/r/image-tiff), in the ME 4Ch and in the AP 4Ch.

METHODS

Twenty-five consecutive adult patients undergoing on-pump cardiac surgery from February 2017 to July 2017 were included. Both TTE and TEE measurements were obtained under anesthesia in a randomized order in the AP 4Ch, ME 4Ch, and DTG views. Within-patient average values were compared by paired t tests with a Bonferroni adjustment. Box plots, correlation, and agreement by Bland-Altman were examined for all 3 comparisons. A second echocardiographer independently acquired and analyzed images; images were reanalyzed after 4 weeks. Image quality and reproducibility were also reported.

RESULTS

Averaged JOURNAL/asag/04.03/00000539-202105000-00029/inline-graphic4/v/2021-04-15T211206Z/r/image-tiff measurements were lower in the ME 4Ch than in the AP 4Ch (6.6 ± 1.7 cm/s vs 7.0 ± 1.5 cm, P = .028; within-patient difference mean ± standard deviation: 0.6 ± 1.2 cm/s). An alternative TEE view for JOURNAL/asag/04.03/00000539-202105000-00029/inline-graphic5/v/2021-04-15T211206Z/r/image-tiff, the DTG, also exhibited lower mean values (6.0 ± 1.6 cm/s, P = .006; within-patient difference mean ± standard deviation: 1.1 ± 1.8 cm/s). JOURNAL/asag/04.03/00000539-202105000-00029/inline-graphic6/v/2021-04-15T211206Z/r/image-tiff strain rate showed a low degree of bias, but greater variability (ME 4Ch: 0.87 ± 0.32%/s vs AP 4Ch: 0.73 ± 0.18%/s, P = .078; within-patient difference mean ± standard deviation: -0.1 ± 0.2%/s).

CONCLUSIONS

This study confirms that TEE modestly underestimates JOURNAL/asag/04.03/00000539-202105000-00029/inline-graphic7/v/2021-04-15T211206Z/r/image-tiff but not to a clinically relevant extent. While JOURNAL/asag/04.03/00000539-202105000-00029/inline-graphic8/v/2021-04-15T211206Z/r/image-tiff in the DTG is not a promising alternative, the future role for speckle tracking-based early diastolic strain rate is unknown.

Rapid, Single-View Speckle-Tracking-Based Method for Examining Left Ventricular Systolic and Diastolic Function in Point of Care Ultrasound

OBJECTIVES

A rapid, reliable quantitative assessment of left ventricular systolic and diastolic function is important for patient treatment in urgent and dynamic settings. Quantification of annular velocities based on a single 2-dimensional image loop, rather than on Doppler velocities, could be useful in point-of-care or focused cardiac ultrasound. We hypothesized that novel speckle-tracking-based mitral annular velocities would correlate with reference standard tissue Doppler imaging (TDI) velocities in a focused cardiac ultrasound-esque setting.

METHODS

Two echocardiographers each performed transthoracic echocardiographic measurements before and after induction of anesthesia in supine patients undergoing cardiac surgery. Speckle-tracking echocardiography (STE)-based systolic (S'_STE ) and diastolic (E'_STE and A'_STE ) velocities were compared to TDI and global longitudinal strain/strain rate. We also compared mitral annular displacement by speckle tracking with M-mode imaging.

RESULTS

Twenty-five patients were included and examined in both preinduction and postinduction states. Speckle-tracking-based velocities correlated with TDI measurements in both states (S', r = 0.73 and 0.76; E', r = 0.87 and 0.65; and A', r = 0.65 and 0.73), showing a mean bias of 25% to 30% of the reference standard measurement. The correlation of S'_STE with strain and the strain rate (S-wave) and E'_STE with the strain rate (E-wave) was good in awake, spontaneously breathing patients but was less strong in the ventilated state. Similarly, displacement by speckle tracking correlated with M-mode measurements in both states (r = 0.91 and 0.84). Measurements required medians of 31 and 34 seconds; reproducibility was acceptable for S'_STE and E'_STE .

CONCLUSIONS

Speckle-tracking-based mitral annular velocities and displacement correlate well with conventional measures as well as with deformation imaging. They may be clinically useful in rapidly assessing both systolic and diastolic function from a single 2-dimensional image loop.

Right Ventricular Systolic Assessment by Transesophageal Versus Transthoracic Echocardiography: Displacement, Velocity, and Myocardial Deformation

OBJECTIVE

First, to compare tricuspid annular displacement and velocity in transthoracic and transesophageal echocardiography (TTE, TEE) using conventional angle-dependent technologies. Second, to evaluate both alternative TEE views as well as an alternative technology (speckle tracking) for overcoming proposed differences in TTE and TEE.

DESIGN

Prospective, comparative, cross-over study with a randomized order of image acquisition.

SETTING

University hospital.

PARTICIPANTS

Adults undergoing cardiac surgery.

INTERVENTIONS

Postinduction standardized image acquisition and analysis in TTE and TEE by 2 echocardiographers.

MEASUREMENTS AND MAIN RESULTS

The authors measured tricuspid annular plane systolic excursion (TAPSE) by M-mode and velocity by tissue Doppler (S') in the apical 4-chamber TTE view and midesophageal 4-chamber TEE view (AP4C, ME4C). They then examined (1) the same measurements in alternative TEE views with proposed better ultrasound angulation; and (2) speckle tracking-based endpoints (TAPSE by speckle tracking, strain, and strain rate). Data were available in 24 of 25 patients. Conventional TAPSE by M-mode and velocity by tissue Doppler (TDI) were underestimated in the ME4C compared with the AP4C reference (mean ± standard deviation: TAPSE: 13.1 ± 3.8 mm v 17.3 ± 4.0 mm; S': 6.7 ± 2.1 cm/s v 9.1 ± 2.2 cm/s; both p < 0.001). Neither a modified deep transgastric view (TAPSE 14.5 ± 4.7 mm, p = 0.017; S' 6.8 ± 1.8 cm/s, p < 0.001) nor a transgastric right ventricular inflow view (TAPSE 12.3 ± 4.0 mm, p = 0.001; S' 6.0 ± 1.3 cm/s, p < 0.001) was similar to the AP4C. Speckle tracking TAPSE was unbiased but with high variability (mean bias = -0.3 mm, 95% limits of agreement = -9.1 to 8.4); strain and strain rate were higher in TEE than for TTE (-17.7 ± 3.6 v -12.6 ± 2.1, p < 0.001; -1.0 ± 0.2/s v -0.7 ± 0.1/s, p < 0.001).

CONCLUSIONS

Right ventricular displacement, velocity, and myocardial deformation measured by TEE versus TTE are different. Neither alternative transesophageal echocardiography views nor speckle tracking-based deformation is promising; TAPSE by speckle tracking is unbiased but imprecise.

Assessing Right Ventricular Function in the Perioperative Setting, Part II: What About Catheters?

An-depth assessment of right ventricular function is important in a many perioperative settings. After exploring 2-dimensional echo-based evaluation, other proposed monitoring modalities are discussed. Pressure-based methods of right ventricular appraisal is discussed. Flow-based assessment is reviewed. An overview of the state of current right ventricular 3-dimensional echocardiography and its potential to construct clinical pressure-volume loops in conjunction with pressure measurements is provided. An overview of right ventricular assessment modalities that do not rely on 2-dimensional echocardiography is discussed. Tailored selection of monitoring modalities can be of great benefit for the perioperative physician. Integrating modalities offers optimal estimations of right ventricular function.

Differences in Two- and Three-Dimensional Assessment of the Mitral Valve by Novices and Experts, Illustrated Using Anterior Mitral Valve Leaflet Length

OBJECTIVES

In this measurement validation study, the authors evaluated agreement between 2-dimensional (2D) and three-dimensional (3D) transesophageal echocardiography (TEE), measuring anterior mitral valve leaflet length by both novice and experienced echocardiographers.

DESIGN

This was a retrospective, observational study.

SETTING

Single university hospital.

PARTICIPANTS

Analyses on datasets from 44 patients.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Fifty datasets from 44 patients with mitral regurgitation were analyzed by 4 observers (2 novices, 2 experts). All observers measured the anterior mitral valve leaflet length from end-systolic 2D TEE images from the midesophageal longitudinal axis view and 3D software-augmented TEE images. The overall mean anterior mitral valve leaflet length was significantly shorter with 3D versus 2D TEE measurements (24.6 ± 4.5 mm v 26.2 ± 5.3 mm; p < 0.001), with novices measuring shorter leaflets than experts for both techniques (p < 0.001 and p = 0.005, respectively). Bland-Altman plots of 3D and 2D TEE measurements showed mean biases (95% limits of agreement) of -1.6 mm (-9.0 to 5.9 mm), -1.8 mm (-9.6 to 6.0 mm), and -1.3 mm (-8.4 to 5.7 mm) for all observers, novices, and experts, respectively. For 2D measurements, interobserver reliability was very strong among experts and strong among novices (Pearson's r = 0.83 v 0.66; p = 0.055). For 3D measurements, interobserver reliability was strong in experts and moderate in novices (Pearson's r = 0.69 v 0.51; p = 0.168).

CONCLUSION

For both novices and experts, 3D TEE measurements of the anterior mitral valve leaflet were significantly shorter than 2D measurements. Interobserver reliability was lowest for novices making 3D TEE measurements, indicating that reliable, quantitative evaluation of 3D TEE may require a greater amount of practice.

Osseointegrative effect of rhBMP-2 covalently bound on a titan-plasma-spray-surface after modification with chromosulfuric acid in a large animal bone gap-healing model with the Göttingen minipig

BACKGROUND

Bone morphogenetic proteins play an important role as osseointegrative factors. It is used widely in orthopedic research and surgery to enhance the osseointegrative potential of implants, e.g., in spinal fusion or alveolar socket augmentation. The aim of the present study was to investigate the benefit of rhBMP-2 on a titan plasma spray (TPS) layer after a special modification with chromosulfuric acid (CSA) at different postoperative times, regarding osseoconduction and osseoinduction.

METHODS

We allocated 27 Göttinger minipigs into three groups consisting of nine animals each. They received four dumbbell-shaped implants in the metaphyseal parts of the femora. The implants had a TPS surface with (CSA group) and without a CSA treatment (TPS group). The former received an additional layer of BMP-2 (BMP-2 group). For the assessment of osseointegration after healing periods of 4, 8, and 12 weeks, histomorphometry was applied to undecalcified specimens after staining according to Masson-Goldner. An intravital labeling with different fluorochromes was used in the gap model. A multivariable analysis with repeated measurement design was performed for statistical evaluation.

RESULTS

We observed several statistical differences in a three-way ANOVA. The comparison between the BMP-2 and the TPS group (two-way ANOVA) showed statistically significant differences in terms of the osseoinduction (osteoid volume), and pronounced for the osseoconduction (bone and osteoid ongrowth), in favor of the BMP-2 group. In the pairwise comparison between BMP-2 and CSA (two-way ANOVA), no statistical significance occurred. The intravital staining with tetracycline, calcein green, and xylenol orange revealed no considerable differences between the groups.

CONCLUSION

BMP-2, covalently bound on a CSA-treated TPS surface, has positive effects on the osseointegration in the large animal bone gap-healing model over the observation period of 12 weeks.

Association of Troponin Trends and Cardiac Morbidity and Mortality After On-Pump Cardiac Surgery

BACKGROUND

Elevated, single-measure, postoperative troponin is associated with adverse events after cardiac surgery. We hypothesized that increases in troponin from the first to the second postoperative day are also associated with all-cause, 12-month mortality and major adverse cardiac events (MACE).

METHODS

This observational study included consecutive adults undergoing on-pump cardiac surgery with cardiac arrest. Troponin T was measured on the first and second postoperative day and was classified as "increasing" (>10%), "unchanged" (10% to -10%), or "decreasing" (<-10%). The primary endpoint was all-cause, 12-month mortality. Secondary endpoints were all-cause 12-month mortality or MACE and both outcomes at 30 days. The main analysis was by multivariable Cox regression.

RESULTS

Of 1,417 included patients, 99 (7.0%) died and 162 (11.4%) died or suffered MACE at 12 months. A significant interaction (p < 0.001) between first postoperative day troponin and the troponin trend from the first to the second postoperative day on 12-month, all-cause mortality precluded an analysis independent of first postoperative day troponin. Consequently, we stratified patients by their first postoperative day troponin (cutoff, 0.8 μg/L). Increasing troponin was associated with higher mortality in patients with first postoperative day troponin T ≥ 0.8 μg/L (hazard ratio, 1.98; 95% CI, 1.09 to 3.59; p = 0.025).

CONCLUSIONS

Troponin changes from the first to the second postoperative day should not be interpreted without consideration of the first postoperative day troponin concentration. For patients with a first postoperative day troponin ≥ 0.8 μg/L, an increase by more than 10% from the first to the second postoperative day was significantly associated with all-cause, 12-month mortality and other adverse events.

Postoperative High-Sensitivity Troponin and Its Association With 30-Day and 12-Month, All-Cause Mortality in Patients Undergoing On-Pump Cardiac Surgery

BACKGROUND

Troponin T is a predictor of cardiac morbidity and mortality after cardiac surgery with most data examining fourth generational troponin T assays. We hypothesize that postoperative high-sensitivity troponin T (hsTnT) measured in increments of the upper limit of the norm independently predicts 30-day all-cause mortality.

METHODS

We included consecutive patients undergoing on-pump cardiac surgery from February 2010 to March 2012 in a prospective cohort that measured hsTnT at 0600 of the first and second postoperative day. Our primary end point was 30-day, all-cause mortality. The secondary end point was 12-month, all-cause mortality in patients surviving the first 30 days. We divided hsTnT into 5 predetermined categorizes based on the upper limit of the norm (ULN). We used Cox regression to examine an association of hsTnT independent of the EuroSCORE II at both 30 days as well as at 12 months in patients surviving the first 30 days. We assessed the area under the receiver operating characteristics curve and the net reassignment improvement for examining the benefit of adding of hsTnT to the EuroSCORE II for prognostication and restratification of 30-day, all-cause mortality.

RESULTS

We included 1122 of 1155 eligible patients (75% male; mean age 66 ± 11 years). We observed 58 (5.2%) deaths at 30 days and another 35 (3.4%) deaths at 12 months in patients surviving 30 days. HsTnT categorized by ULN exhibited a graded response for the mortality. Furthermore, hsTnT remained an independent predictor of all-cause mortality at 30 days (adjusted hazard ratio 1.019 [1.014-1.024] per 10-fold increase in ULN) as well as at 12 months (adjusted hazard ratio 1.019 [1.007-1.032]) in patients surviving the first 30 days. The addition of hsTnT to the EuroSCORE II significantly increased the area under the receiver operating characteristics curve (area under curve: 0.816 [95% confidence interval, 0.754-0.878] versus area under curve: 0.870 [95% confidence interval, 0.822-0.917], respectively; P = .012). Finally, adding hsTnT to the EuroSCORE II improved restratification by the net reassignment improvement, primarily by improving rule-out of events.

CONCLUSIONS

This analysis suggests that, similar to previous assays, higher postoperative concentrations of hsTnT are independently associated with all-cause mortality in patients undergoing on-pump cardiac surgery.

Absolute Postoperative B-Type Natriuretic Peptide Concentrations, but Not Their General Trend, Are Associated With 12-Month, All-Cause Mortality After On-Pump Cardiac Surgery

BACKGROUND

B-type natriuretic peptide (BNP) is a predictor of mortality after on-pump cardiac surgery. However, previous limited and heterogeneous studies have focused on peak concentrations at 3 to 5 days after surgery and may not offer clinicians much help in early decision-making. After confirming the predictive value of first-postoperative-day BNP in a preliminary analysis, we explored the association between isolated second-postoperative-day BNP concentrations, second-day BNP concentrations in conjunction with first-day BNP concentrations, and the change in BNP (ie, ΔBNP) from the first to the second postoperative day and 12-month, all-cause mortality.

METHODS

We included consecutive patients undergoing on-pump cardiac surgery in this observational, secondary analysis of prospectively collected data. We analyzed biomarkers on the first and second postoperative day. ΔBNP was defined as BNP on the second postoperative day minus BNP on the first postoperative day. The primary end point was 12-month, all-cause mortality. The secondary end point was a composite of major adverse cardiac events (MACEs) at 12 months and/or all-cause mortality at 12 months. MACE was defined as nonfatal cardiac arrest, myocardial infarction, and congestive heart failure. The association between BNP and outcomes was examined by receiver operating characteristic curves, as well as univariate and multivariable logistic regression, adjusting for the EuroSCORE II, cross-clamp time, and first-postoperative-day troponin T.

RESULTS

We included 1199 patients in the preliminary analysis focused on BNP on postoperative day 1. In the analyses examining BNP variables requiring second-postoperative-day BNP measurement (n = 708), we observed 66 (9.3%) deaths, 48 (6.8%) MACE, and 104 (14.7%) deaths and/or MACE. Both first- and second-postoperative-day BNP were significant independent predictors of all-cause, 12-month mortality per 100 ng/L increase (adjusted odds ratio [aOR], 1.040 [95% confidence interval (CI), 1.019-1.065] and 1.064 [95% CI, 1.031-1.105], respectively). When used in conjunction with one another, first-day BNP was not significant (aOR, 1.021 [95% CI, 0.995-1.048]), while second-day BNP remained significant (aOR, 1.046 [95% CI, 1.008-1.091]). The ΔBNP per 100 ng/L increase was not associated with 12-month, all-cause mortality in the univariable (OR, 0.977 [95% CI, 0.951-1.007]) or multivariable analysis (aOR, 0.989 [95% CI, 0.962-1.021]).

CONCLUSIONS

Both absolute concentrations of first- and second-postoperative-day BNP are independent predictors of 12-month, all-cause mortality. When modeled together, second-postoperative-day BNP is more predictive of 12-month, all-cause mortality. Although intuitively appealing, the change in BNP from the first to the second postoperative day is a complex variable and should not routinely be used for prognostication.

Analysis of the osseointegrative force of a hyperhydrophilic and nanostructured surface refinement for TPS surfaces in a gap healing model with the Göttingen minipig

Background

A lot of advantages can result in a high wettability as well as a nanostructure at a titanium surface on bone implants. Thus, the aim of this study was to evaluate the osseointegrative potential of a titan plasma-sprayed (TPS) surface refinement by acid-etching with chromosulfuric acid. This results in a hyperhydrophilic surface with a nanostructure and an extreme high wetting rate.

Methods

In total, 72 dumbbell shape titan implants were inserted in the spongy bone of the femora of 18 Göttingen minipigs in a conservative gap model. Thirty-six titan implants were coated with a standard TPS surface and 36 with the hyperhydrophilic chromosulfuric acid (CSA) surface. After a healing period of 4, 8, and 12 weeks, the animals were killed. The chronological healing process was histomorphometrically analyzed.

Results

The de novo bone formation, represented by the bone area (BA), is increased by approximately 1.5 times after 12 weeks with little additional benefit by use of the CSA surface. The bone-to-implant contact (BIC), which represents osseoconductive forces, shows results with a highly increased osteoid production in the CSA implants beginning at 8 and 12 weeks compared to TPS. This culminates in a 17-fold increase in BIC after a healing period of 12 weeks. After 4 weeks, significantly more osteoid was seen in the gap as de novo formation in the CSA group (p = 0.0062). Osteoid was also found more frequently after 12 weeks at the CSA-treated surface (p = 0.0355). The site of implantation, intertrochanteric or intercondylar, may influence on the de novo bone formation in the gap.

Conclusions

There is a benefit by the CSA surface treatment of the TPS layer for osseointegration over an observation time up to 12 weeks. Significant differences were able to be shown in two direct comparisons between the CSA and the TPS surface for osteoid formation in the gap model. Further trials may reveal the benefit of the CSA treatment of the TPS layer involving mechanical tests if possible.

Electronic supplementary material

The online version of this article (doi:10.1186/s13018-016-0434-6) contains supplementary material, which is available to authorized users.

Gastric rupture after bag-mask-ventilation

A 42 year old woman underwent bronchoscopy with procedural propofol sedation. During the procedure, the patient suffered respiratory arrest, and bag-mask ventilation was initiated. During forced mask ventilation, abdominal distention occurred. Even after correct placement of an endotracheal and a nasogastric tube, high inspiratory pressures persisted. The abdominal CT scan revealed a high amount of intraperitoneal free air. An emergent laparotomy confirmed a stomach rupture. Immediately after opening of the peritoneal cavity, peak ventilatory pressures decreased. In this case forceful bag-mask ventilation led to air insufflation into the stomach, increasing gastric pressure, and consecutive stomach rupture.

Scintigraphic evaluation of rhBMP-2-biocoated implants reveals no ectopic bone formation

The main objectives of the study described below were of two-fold nature: (1) to examine if rhBMP-2-biocoated implants in a pig model could lead to ectopic bone formation and (2) if quantitative and/or qualitative differences could be found between adhesively and covalently bonded BMP II using the scintigraphic method. In order to examine these central questions, 26 Göttingen minipigs were allocated to three groups with a control group (n=7) and two study groups (n=9 each) receiving one of three implant types: (a) chromosulfuric acid treated titanium surface as control, (b) non-covalently bonded BMP-2, and (c) covalently bonded and immobilized rhBMP-2. Each animal received four barbell-shaped implants, one in the proximal and distal metaphysis of each femur. The scintigraphic analyses were conducted after four, eight, and 12 weeks postoperatively. The visual (qualitative) analysis failed to show ectopic bone formation in any of the three groups. The statistical analysis of the relative values for bone formation yielded no significant differences between the groups, although the limitation in the applied methods do not enable one to draw conclusions regarding the histomophometric results.