Hemodynamic management of patients in the first 24 hours after cardiac surgery

The epidemiology of postoperative dobutamine and phosphodiesterase inhibitors after adult elective cardiac surgery and its impact on the length of hospital stay: a post hoc analysis from the multicenter retrospective observational study

The optimal administration of inotrope after cardiac surgery is unknown. This study aimed to investigate the impact of postoperative inotrope on clinical outcomes in adult elective cardiac surgery patients. Data from the Blood Pressure and Relative Optimal Target after Heart Surgery in Epidemiologic Registry study were analyzed, employing propensity score considering the hospital of admission. The primary outcome was the length of hospital stay evaluated using quantile regression. Secondary outcomes were kidney injury progression, renal replacement therapy, atrial fibrillation, mortality, mechanical ventilation duration, and length of intensive care unit (ICU) stay. Among 870 patients from 14 ICUs in Japan, 535 received inotropes within 24 h of ICU admission, with usage rates ranging from 40 to 100% among facilities. After propensity score matching, 218 patients were included in each group. The inotrope group had a significantly longer hospital stay compared to the control group (16 days vs. 14 days; median difference 1.78 [95% confidence interval [CI] 0.31-3.24]; p = 0.018). However, no significant differences were observed in the secondary outcomes, except for mechanical ventilation duration. The results of the sensitivity analysis using a mixed-effects quantile regression analysis considering the hospital of admission for length of hospital stay in the original cohort were consistent with the results of the propensity analyses (median difference in days, 2.35 [95% CI, 0.35-4.36]; p = 0.022). The use of inotropes within 24 h of ICU admission in adult elective cardiac surgery patients was associated with an extended hospitalization period of approximately 2 days, without offering any prognostic benefit. Clinical trial registration: UMIN-CTR, https://www.umin.ac.jp/ctr/index-j.htm , UMIN000037074.

Agitation during anaesthetic emergence: An observational study of adult cardiac surgery patients in two Australian intensive care units

BACKGROUND

Anaesthetic emergence agitation among adult patients being recovered after open cardiac and/or thoracic aorta surgery has not been described.

OBJECTIVES

The objective of this study was to characterise emergence agitation in terms of incidence, clinical features, and consequences in a cohort of cardiac surgery patients being recovered in the intensive care unit (ICU).

METHODS

A prospective, observational pilot study was implemented. Over a 5-week period, the study was conducted in two metropolitan hospitals in Victoria, Australia. The cohort comprised all patients admitted to the ICUs aged ≥18 years, who had undergone cardiac surgery via an open sternotomy with general anaesthetic, and whose emergence was directly observed. Emergence agitation was defined as a Richmond Agitation and Sedation Scale score of ≥+2.

RESULTS

Fifty patients were observed. Emergence agitation occurred in 24/50 (48%) of patients. Patients with emergence agitation experienced more clinical consequences than patients with calm emergence, including a significantly greater number of episodes of airway compromise (12/24, 50%, p < 0.001); ventilator dyssynchrony (23/24, 96%, p = 0.004); and hypertension (13/24, 54%, p = 0.004). Significant treatment interference (potentially dangerous patient movements such as pulling tubes) occurred with 23/24 patients (96%, p < 0.0001). Patients who underwent emergence agitation required significantly more interventions during anaesthetic emergence than patients who underwent a calm emergence. Interventions included extra nursing measures (16/24, 67%, p = 0.001) administration of sedative and/or opioid intravenous boluses (22/24, 92%, p = 0.001) and vasoactive agents (15/24, 63%, p = 0.05).

CONCLUSIONS

In patients recovering from cardiac surgery in the ICU, emergence agitation was clinically important. Immediate interventions were required to prevent and manage complications.

Systolic Blood Pressure Less Than 120 mmHg is a Safe and Effective Method to Minimize Bleeding After Facelift Surgery: A Review of 502 Consecutive Cases

BACKGROUND

Hematoma is the most common complication after facelift surgery. Hypertension is the major risk factor for hematoma following facelift. Measures taken to reduce systolic blood pressure perioperatively significantly reduce the risk of hematoma. There is evidence that treating systolic blood pressure of 140 mmHg or above reduces hematoma; there were no studies to date in which systolic blood pressures below 120 mmHg had been evaluated.

OBJECTIVES

To assess the safety and efficacy of maintaining systolic blood pressures of 120 mmHg or less postoperatively to reduce hematoma after facelift.

METHODS

A retrospective chart review of a single surgeon's series of facelift procedures from January 2004 to July 2018 was undertaken. Implementation of a more stringent perioperative blood pressure protocol (maintaining a systolic blood pressure of less than 120 mmHg postoperatively) was initiated in January of 2013, dividing patients into 2 groups.

RESULTS

A total of 502 consecutive patients who underwent a facelift by F.N. were included in the study. A total of 319 patients underwent a facelift before 2013, and a total of 183 patients underwent a facelift in 2013 or later. Overall, a total of 13 hematomas occurred during the entire 15-year study period (2.59%), of which 12 occurred before the implementation of a strict blood pressure regimen (3.76%), and only 1 occurred after the new protocol (0.5%). There were no adverse events related to the lower blood pressure.

CONCLUSIONS

Treating systolic blood pressure greater than 120 mmHg postoperatively is a safe and effective method for reducing the risk of hematoma after facelift.

Comparison of Intraoperative and Discharge Residual Lesion Severity in Congenital Heart Surgery

BACKGROUND

While the predischarge technical performance score (DC-TPS) is significantly associated with outcomes after congenital cardiac surgery, the utility of the intraoperative TPS (IO-TPS) remains unknown.

METHODS

This was a single-center retrospective review of consecutive patients who underwent congenital cardiac surgery from January 2011 to December 2019. Intraoperative and predischarge echocardiograms were used to assign IO-TPS and DC-TPS, respectively, for each index operation (class 1, no residua; class 2, minor residua; class 3, major residua). Anatomic modules identifying the principal residual lesion were assigned to all class 2/3 patients. Overall and module-specific TPS comparisons were made. Multivariable regression models with IO-TPS and DC-TPS as separate predictors of postoperative outcomes were compared.

RESULTS

Of 6201 patients, overall agreement between IO-TPS and DC-TPS was observed in 4251 patients (68.6%); scores were likelier to be worse at discharge (P < .001). Paired comparative analyses revealed that among patients with at least class 2 atrioventricular and semilunar valve residua, IO-TPS was likelier to worsen than improve (both P < .001). Class 3 patients had a higher risk of in-hospital/early mortality (IO-TPS: odds ratio, 7.5; 95% CI, 2.4-23; DC-TPS: odds ratio, 6.6; 95% CI, 3.0-15), postdischarge/late mortality (IO-TPS: hazard ratio [HR], 3.1, 95% CI, 1.3-7.1; DC-TPS: HR, 2.3; 95% CI, 1.2-4.4), and late unplanned reintervention (IO-TPS: HR, 2.8; 95% CI, 1.9-4.0; DC-TPS: HR, 3.4; 95% CI, 2.8-4.2) vs class 1 (all P < .05). IO- and DC-TPS models were equivalent fits for predicting early and late mortality; the latter was a marginally better fit for late reintervention.

CONCLUSIONS

IO-TPS and DC-TPS are both important adjuncts for quality improvement in congenital cardiac surgery.

The predictive value of pressure recording analytical method for the duration of mechanical ventilation in children undergoing cardiac surgery with an XGBoost-based machine learning model

Objective

Prolonged mechanical ventilation in children undergoing cardiac surgery is related to the decrease in cardiac output. The pressure recording analytical method (PRAM) is a minimally invasive system for continuous hemodynamic monitoring. To evaluate the postoperative prognosis, our study explored the predictive value of hemodynamic management for the duration of mechanical ventilation (DMV).

Methods

This retrospective study included 60 infants who underwent cardiac surgery. Cardiac index (CI), the maximal slope of systolic upstroke (dp/dt_max), and cardiac cycle efficiency (CCE) derived from PRAM were documented in each patient 0, 4, 8, and 12 h (T0, T1, T2, T3, and T4, respectively) after their admission to the intensive care unit (ICU). A linear mixed model was used to deal with the hemodynamic data. Correlation analysis, receiver operating characteristic (ROC), and a XGBoost machine learning model were used to find the key factors for prediction.

Results

Linear mixed model revealed time and group effect in CI and dp/dt_max. Prolonged DMV also have negative correlations with age, weight, CI at and dp/dt_max at T2. dp/dt_max outweighing CI was the strongest predictor (AUC of ROC: 0.978 vs. 0.811, p < 0.01). The machine learning model suggested that dp/dt_max at T2 ≤ 1.049 or < 1.049 in combination with CI at T0 ≤ 2.0 or >2.0 can predict whether prolonged DMV (AUC of ROC = 0.856).

Conclusion

Cardiac dysfunction is associated with a prolonged DMV with hemodynamic evidence. CI measured by PRAM immediately after ICU admission and dp/dt_max 8h later are two key factors in predicting prolonged DMV.

Definition and incidence of hypotension in intensive care unit patients, an international survey of the European Society of Intensive Care Medicine

INTRODUCTION

Although hypotension in ICU patients is associated with adverse outcome, currently used definitions are unknown and no universally accepted definition exists.

METHODS

We conducted an international, peer-reviewed survey among ICU physicians and nurses to provide insight in currently used definitions, estimations of incidence, and duration of hypotension.

RESULTS

Out of 1394 respondents (1055 physicians (76%) and 339 nurses (24%)), 1207 (82%) completed the questionnaire. In all patient categories, hypotension definitions were predominantly based on an absolute MAP of 65 mmHg, except for the neuro(trauma) category (75 mmHg, p < 0.001), without differences between answers from physicians and nurses. Hypotension incidence was estimated at 55%, and time per day spent in hypotension at 15%, both with nurses reporting higher percentages than physicians (estimated mean difference 5%, p = 0.01; and 4%, p < 0.001).

CONCLUSIONS

An absolute MAP threshold of 65 mmHg is most frequently used to define hypotension in ICU patients. In neuro(trauma) patients a higher threshold was reported. The majority of ICU patients are estimated to endure hypotension during their ICU admission for a considerable amount of time, with nurses reporting a higher estimated incidence and time spent in hypotension than physicians.

Risk factors for chylothorax and persistent serous effusions after congenital heart surgery

OBJECTIVES

This study evaluated the various risk factors for chylothorax and persistent serous effusions (>7 days) after congenital heart surgery and developed equations to calculate the probability of their occurrence.

METHODS

We performed a retrospective review of different medical databases at the University Hospital of Erlangen between January 2014 and December 2016. Full model regression analysis was used to identify risk factors, and prediction algorithms were set up to calculate probabilities. Discriminative power of the models was checked with the help of C-statistics.

RESULTS

Of 745 operations on 667 patients, 68 chylothoraxes (9.1%) and 125 persistent pleural effusions (16.8%) were diagnosed. Lowest temperature [P = 0.043; odds ratio (OR) 0.899], trisomy 21 (P = 0.001; OR 5.548), a higher vasoactive inotropic score on the day of surgery (P = 0.001; OR 1.070) and use of an assist device (P = 0.001; OR 5.779) were significantly associated with chylothorax. Risk factors for persistent serous effusions were a given or possible involvement of the aortic arch during the operation (P = 0.000; OR 3.982 and 2.905), univentricular hearts (P = 0.019; OR 2.644), a higher number of previous heart operations (P = 0.014; OR 1.436), a higher vasoactive inotropic score 72 h after surgery (P = 0.019; OR 1.091), a higher central venous pressure directly after surgery (P = 0.046; OR 1.076) and an aortic cross-clamp time >86 min (P = 0.023; OR 2.223), as well as use of an assist device (P = 0.002; OR 10.281). The prediction models for both types of effusions proved to have excellent discriminative power.

CONCLUSIONS

Persistent serous effusion is associated with a higher vasoactive inotropic score 72 h after surgery, an aortic cross-clamp time >86 min and elevated central venous pressure directly after surgery, which, in combination, potentially indicate cardiac stress. The developed logistic algorithm helps to estimate future likelihood.

Fluid responsiveness to passive leg raising in patients with and without coronary artery disease: A prospective observational study

Introduction:

Hemodynamic stability and fluid responsiveness (FR) assume importance in perioperative management of patients undergoing major surgery. Passive leg raising (PLR) is validated in assessing FR in intensive care unit patients. Very few studies have examined FR to PLR in intraoperative scenario. We prospectively studied FR to PLR using transesophageal echocardiography (TEE), in patients with no coronary artery disease (CAD) undergoing major neurosurgery and those with CAD undergoing coronary artery bypass grafting (CABG).

Methods:

We enrolled 29 adult consenting patients undergoing major neurosurgery with TEE monitoring and 25 patients undergoing CABG. After induction of anesthesia, baseline hemodynamic parameters were obtained which was followed by PLR using automated adjustment of the operating table. Clinical and TEE-derived hemodynamic parameters were recorded at 1 and 10 min after PLR following which patients were returned to supine position.

Results:

A total of 162 TEE and clinical examinations were done across baseline, 1 and 10 min after PLR; and paired comparison was done at data intervals of baseline versus 1 min PLR, baseline versus 10 min PLR, and 1 min versus 10 min PLR. There was no significant change in hemodynamic variables at any of the paired comparison intervals in patients undergoing neurosurgery. CABG cases had significant hemodynamic improvement 1 min after PLR, partially sustained at 10 min.

Conclusion:

Patients undergoing CABG had significant hemodynamic response to PLR, whereas non-CAD patients undergoing neurosurgery did not. A blood pressure–left ventricular end-diastolic volume combination represented strong correlation in response prediction (Pearson's coefficient 0.641; P < 0.01).

Changes in Stroke Volume Variation Induced by Passive Leg Raising to Predict Fluid Responsiveness in Cardiac Surgical Patients With Protective Ventilation

OBJECTIVES

Stroke volume variation (SVV) has been used to predict fluid responsiveness. The authors hypothesized the changes in SVV induced by passive leg raising (PLR) might be an indicator of fluid responsiveness in patients with protective ventilation after cardiac surgery.

DESIGN

A prospective single-center observational study.

SETTING

A single cardiac surgery intensive care unit at a tertiary hospital.

PARTICIPANTS

A total of 123 patients undergoing cardiac surgery with hemodynamic instability. Tidal volume was set between 6 and 8 mL/kg of ideal body weight.

INTERVENTIONS

PLR maneuver, fluid challenge.

MEASUREMENTS AND MAIN RESULTS

SVV was continuously recorded using pulse contour analysis before and immediately after a PLR test and after fluid challenge (500 mL of colloid given over 30 min). Sixty-three (51.22%) patients responded to fluid challenge, in which PLR and fluid challenge significantly increased the SV and decreased the SVV. The decrease in SVV induced by PLR was correlated with the SV changes induced by fluid challenge. A 4% decrease in the SVV induced by PLR-discriminated responders to fluid challenge with an area under the curve of 0.90. The gray zone identified a range of SVV changes induced by PLR (between -3.94% and -2.91%) for which fluid responsiveness could not be predicted reliably. The gray zone included 15.45% of the patients. The SVV at baseline predicted fluid responsiveness with an area under the curve of 0.72.

CONCLUSIONS

Changes in the SVV induced by PLR predicted fluid responsiveness in cardiac surgical patients with protective ventilation.

Evaluation of radial artery pulse pressure effects on detection of stroke volume changes after volume loading maneuvers in cardiac surgical patients

BACKGROUND

Fluid responsiveness is defined as an increase in cardiac output (CO) or stroke volume (SV) of >10-15% after fluid challenge (FC). However, CO or SV monitoring is often not available in clinical practice. The aim of this study was to evaluate whether changes in radial artery pulse pressure (rPP) induced by FC or passive leg raising (PLR) correlates with changes in SV in patients after cardiac surgery.

METHODS

This prospective observational study included 102 patients undergoing cardiac surgery, in which rPP and SV were recorded before and immediately after a PLR test and FC with 250 mL of Gelofusine for 10 min. SV was measured using pulse contour analysis. Patients were divided into responders (≥15% increase in SV after FC) and non-responders. The hemodynamic variables between responders and non-responders were analyzed to assess the ability of rPP to track SV changes.

RESULTS

A total of 52% patients were fluid responders in this study. An rPP increase induced by FC was significantly correlated with SV changes after a FC (ΔSV-FC, r=0.62, P<0.01). A fluid-induced increase in rPP (ΔrPP-FC) of >16% detected a fluid-induced increase in SV of >15%, with a sensitivity of 91% and a specificity of 73%. The area under the receiver operating characteristic curve (AUROC) for the fluid-induced changes in rPP identified fluid responsiveness was 0.881 (95% CI: 0.802-0.937). A grey zone of 16-34% included 30% of patients for ΔrPP-FC. The ΔrPP-PLR was weakly correlated with ΔSV-FC (r=0.30, P<0.01). An increase in rPP induced by PLR (ΔrPP-PLR) predicted fluid responsiveness with an AUROC of 0.734 (95% CI: 0.637-0.816). A grey zone of 10-23% included 52% of patients for ΔrPP-PLR.

CONCLUSIONS

Changes in rPP might be used to detect changes in SV via FC in mechanically ventilated patients after cardiac surgery. In contrast, changes in rPP induced by PLR are unreliable predictors of fluid responsiveness.

Exercise is feasible in patients receiving vasoactive medication in a cardiac surgical intensive care unit: A prospective observational study

BACKGROUND

Patients may require vasoactive medication after cardiac surgery. The effect and safety profile of exercise on haemodynamic parameters in these patients is unclear.

OBJECTIVES

The objective of this study was to measure the effect of upright positioning and low-level exercise on haemodynamic parameters in patients after cardiac surgery who were receiving vasoactive therapy and to determine the incidence of adverse events.

METHODS

This was a prospective, single-centre, observational study conducted in an adult intensive care unit of a tertiary, cardiothoracic university-affiliated hospital in Australia. The Flotrac-Vigileo™ system was used to measure haemodynamic changes, including cardiac output, cardiac index, and stroke volume. Normally distributed variables are presented as n (%) and mean (standard deviation), and non-normally distributed variables are presented as median [interquartile range].

RESULTS

There were a total of 20 participants: 16 (80%) male, with a mean age of 65.9 (10.6) years. Upright positioning caused significant increases (p = 0.018) in the mean arterial pressure (MAP), with MAP readings increasing from baseline (supine), from 72.31 (11.91) mmHg to 77.44 (9.55) mmHg when back in supine. There were no clinically significant changes in cardiac output, heart rate, stroke volume, or cardiac index with upright positioning. The incidence of adverse events was low (5%). The adverse event was transient hypotension of low severity.

CONCLUSIONS

Low-level exercise in patients after cardiac surgery receiving vasoactive medication was well tolerated with a low incidence of adverse events and led to significant increases in MAP. Upright positioning and low-level exercise appeared safe and feasible in this patient cohort.

Skeletal muscle microvasculature response to β-adrenergic stimuli is diminished with cardiac surgery

BACKGROUND

Cardiac surgery and cardiopulmonary bypass are associated with alterations in blood pressure in the perioperative period, which, if uncontrolled, can result in end organ damage or dysfunction. Microvessels, significant contributors to blood pressure, both in the myocardium and peripheral skeletal muscle, have diminished responsiveness to major mediators of vascular tone, including thromboxane and serotonin after cardiopulmonary bypass. Responsiveness of these vessels to β-adrenergic stimulation, a major mediator of vascular tone, has not yet been studied. In this report, we investigated the role of β-adrenergic receptors in vascular tone regulation in human skeletal muscle microvessels before and after β-adrenergic stimulation.

METHODS

Skeletal muscle microvessels were isolated from patients undergoing cardiac surgery before and after cardiopulmonary bypass. Vessels were exposed in an ex vivo model to the β-adrenergic agonist isoproterenol, or the direct adenylyl cyclase activator, forskolin, and the selective β-receptor antagonist ICI18.551 hydrochloride plus isoproterenol. Immunofluorescence of β receptors and Western blotting were also performed.

RESULTS

Microvessels showed diminished responsiveness to isoproterenol (10^-6 to 10^-4M) after cardiopulmonary bypass (n = 8/group, P = .01). Pretreatment with the selective β-2 blocker ICI18.551 (10^-6M) prevented isoproterenol-induced microvascular relaxation (P = .001). Forskolin-induced relaxation response was also significantly diminished after cardiopulmonary bypass (n = 4/group, P < .05 versus before cardiopulmonary bypass). No significant changes in the total protein expression of β-1, β-2, and β-3 receptors were detected by western blotting or immunofluorescence.

CONCLUSION

Microvessels isolated from human skeletal muscle show diminished responsiveness to isoproterenol and its downstream activator forskolin after cardiopulmonary bypass, suggesting there is an alteration in β-adrenergic receptor responsive in adenylate cyclase. The relaxation response to isoproterenol was via activation β-2 receptors without changes in β-adrenergic receptor abundance.

Akt is a critical node of acute myocardial insulin resistance and cardiac dysfunction after cardiopulmonary bypass

AIMS

Acute myocardial insulin resistance is an independent risk factor for patients who undergo cardiac surgery with cardiopulmonary bypass (CPB). However, the underlying mechanism of insulin resistance during CPB has not been fully investigated.

MATERIALS AND METHODS

To explore the role of myocardial insulin resistance on the cardiac function and its underlying mechanism, CPB operation and pharmacological intervention were applied in mini pigs, and myocardial insulin signaling, glucose uptake, ATP production and cardiac function were examined.

KEY FINDINGS

Our data showed that CPB elicited not only hyperglycemia and hyperinsulinemia, but also inactivated Akt, and impaired the transposition of membrane glucose transporter-4 (GLUT-4), reduced glucose uptake and ATP production in the myocardium as well, which in turn was accompanied with cardiac dysfunction. Meanwhile, linear correlations were established among reduced myocardial glucose uptake, ATP production, and depressed cardiac systolic or diastolic function. Reactivation of Akt by SC79, an Akt agonist, partially alleviated myocardial insulin resistance and restored post CPB cardiac function via augmenting myocardial glucose uptake and ATP production.

SIGNIFICANCE

These findings revealed that acute myocardial insulin resistance due to inactivation of Akt played a key role in cardiac dysfunction post CPB via suppressing glucose metabolism related energy supply.

Reliability of three-dimensional color flow Doppler and two-dimensional pulse wave Doppler transthoracic echocardiography for estimating cardiac output after cardiac surgery

BACKGROUND

Three-dimensional color flow Doppler (3DCF) is a new convenient technique for cardiac output (CO) measurement. However, to date, no one has evaluated the accuracy of 3DCF echocardiography for CO measurement after cardiac surgery. Therefore, this single-center, prospective study was designed to evaluate the reliability of three-dimensional color flow and two-dimensional pulse wave Doppler (2D-PWD) transthoracic echocardiography for estimating cardiac output after cardiac surgery.

METHODS

Post-cardiac surgical patients with a good acoustic window and a low dose or no dose of vasoactive drugs (norepinephrine < 0.05 μg/kg/min) were enrolled for CO estimation. Three different methods (third generation FloTrac/Vigileo™ [FT/V] system as the reference method, 3DCF, and 2D-PWD) were used to estimate CO before and after interventions (baseline, after volume expansion, and after a dobutamine test).

RESULTS

A total of 20 patients were enrolled in this study, and 59 pairs of CO measurements were collected (one pair was not included because of increasing drainage after the dobutamine test). Pearson's coefficients were 0.260 between the CO-FT/V and CO-PWD measurements and 0.729 between the CO-FT/V and CO-3DCF measurements. Bland-Altman analysis showed the bias between the absolute values of CO-FT/V and CO-PWD measurements was - 0.6 L/min with limits of agreement between - 3.3 L/min and 2.2 L/min, with a percentage error (PE) of 61.3%. The bias between CO-FT/V and CO-3DCF was - 0.14 L/min with limits of agreement between - 1.42 L /min and 1.14 L/min, with a PE of 29.9%. Four-quadrant plot analysis showed the concordance rate between ΔCO-PWD and ΔCO-3FT/V was 93.3%.

CONCLUSIONS

In a comparison with the FT/V system, 3DCF transthoracic echocardiography could accurately estimate CO in post-cardiac surgical patients, and the two methods could be considered interchangeable. Although 2D-PWD echocardiography was not as accurate as the 3D technique, its ability to track directional changes was reliable.

Perioperative Management of the Cardiac Transplant Recipient

Management of the cardiac transplant recipient includes careful titration of inotropes and vasopressors. Recipient pulmonary hypertension and ventilatory status must be optimized to prevent allograft right ventricular failure. Vasoplegia, coagulopathy, arrhythmias, and renal dysfunction also require careful management to achieve an optimal outcome. Primary graft dysfunction (PGD) can be an ominous problem after cardiac transplantation. Although mild degrees of PGD may be managed medically, mechanical circulatory support with extracorporeal membrane oxygenation or temporary ventricular assist devices may be required. Retransplantation may be necessary in some cases.

Effects of levosimendan on mortality in patients undergoing cardiac surgery: A systematic review and meta-analysis

PURPOSE

We sought to determine the impact of levosimendan on mortality following cardiac surgery based on large-scale randomized controlled trials (RCTs).

METHODS

We searched PubMed, Web of Science, Cochrane databases, and ClinicalTrials.gov for RCTs published up to December 2017, on levosimendan for patients undergoing cardiac surgery.

RESULTS

A total of 25 RCTs enrolling 2960 patients met the inclusion criteria; data from 15 placebo-controlled randomized trials were included for meta-analysis. Pooled analysis showed that the all-cause mortality rate was 6.4% (71 of 1106) in the levosimendan group and 8.4% (93 of 1108) in the placebo group (odds ratio [OR], 0.76; 95% confidence interval [CI], 0.55-1.04; P = 0.09). There were no significant differences between the two groups in the rates of myocardial infarction (OR: 0.91; 95% CI, 0.68-1.21; P = 0.52), serious adverse events (OR: 0.84; 95% CI, 0.66-1.07; P = 0.17), hypotension (OR: 1.69; 95% CI, 0.94-3.03; P = 0.08), and low cardiac output syndrome (OR: 0.47; 95% CI, 0.22-1.02; P = 0.05).

CONCLUSION

Levosimendan did not result in a reduction in mortality in adult cardiac surgery patients. Well designed, adequately powered, multicenter trials are necessary to determine the role of levosimendan in adult cardiac surgery.

Levosimendan for Hemodynamic Support after Cardiac Surgery

BACKGROUND

Acute left ventricular dysfunction is a major complication of cardiac surgery and is associated with increased mortality. Meta-analyses of small trials suggest that levosimendan may result in a higher rate of survival among patients undergoing cardiac surgery.

METHODS

We conducted a multicenter, randomized, double-blind, placebo-controlled trial involving patients in whom perioperative hemodynamic support was indicated after cardiac surgery, according to prespecified criteria. Patients were randomly assigned to receive levosimendan (in a continuous infusion at a dose of 0.025 to 0.2 μg per kilogram of body weight per minute) or placebo, for up to 48 hours or until discharge from the intensive care unit (ICU), in addition to standard care. The primary outcome was 30-day mortality.

RESULTS

The trial was stopped for futility after 506 patients were enrolled. A total of 248 patients were assigned to receive levosimendan and 258 to receive placebo. There was no significant difference in 30-day mortality between the levosimendan group and the placebo group (32 patients [12.9%] and 33 patients [12.8%], respectively; absolute risk difference, 0.1 percentage points; 95% confidence interval [CI], -5.7 to 5.9; P=0.97). There were no significant differences between the levosimendan group and the placebo group in the durations of mechanical ventilation (median, 19 hours and 21 hours, respectively; median difference, -2 hours; 95% CI, -5 to 1; P=0.48), ICU stay (median, 72 hours and 84 hours, respectively; median difference, -12 hours; 95% CI, -21 to 2; P=0.09), and hospital stay (median, 14 days and 14 days, respectively; median difference, 0 days; 95% CI, -1 to 2; P=0.39). There was no significant difference between the levosimendan group and the placebo group in rates of hypotension or cardiac arrhythmias.

CONCLUSIONS

In patients who required perioperative hemodynamic support after cardiac surgery, low-dose levosimendan in addition to standard care did not result in lower 30-day mortality than placebo. (Funded by the Italian Ministry of Health; CHEETAH ClinicalTrials.gov number, NCT00994825 .).

Early postoperative blood pressure and blood loss after cardiac surgery: A retrospective analysis

BACKGROUND

Increased blood loss after cardiac surgery is a risk factor for patient morbidity and mortality. Guidelines for postoperative haemodynamics management recommend normotensive blood pressure to avoid increased chest drain volumes. The aim of this study was to verify the correlation of early postoperative hypertension and blood loss in patients after cardiac surgery during the early postoperative period.

METHODS

Postoperative mean blood pressure values and chest drain volumes of 431 patients were registered by an intensive care monitoring system during first 60minutes after intensive care admission. Correlation between blood pressure and blood loss was calculated by linear regression analysis.

RESULTS

In the entire patient cohort and in various subgroup analyses (body-mass-index, type of surgery, comorbidity, emergency surgery, preoperative anticoagulation therapy) no association between early mean blood pressure >80mmHg and increased blood loss was evident in simple regression analysis. Merely, after aortic surgery a correlation of hypertension and blood loss was found. Multiple regression revealed postoperative INR values >1.5 and thrombocyte counts <100.000/nL to impact blood loss in contrast to postoperative hypertension.

CONCLUSION

Evidence for strict blood pressure management to reduce blood loss after cardiac surgery is scarce. Instead, in face of higher INR and low thrombocytes increasing postoperative blood loss, achieving and maintaining a physiological coagulation is essential.

Ultrasonographic caval indices do not significantly contribute to predicting fluid responsiveness immediately after coronary artery bypass grafting when compared to passive leg raising

Background

Appropriate fluid management is one of the most important elements of early goal-directed therapy after cardiothoracic surgery. Reliable determination of fluid responsivenss remains the fundamental issue in volume therapy.

The purpose of the study was to assess the usefulness of dynamic IVC-derived parameters (collapsibility index, distensibility index) in comparison to passive leg raising, in postoperative fluid management in mechanically ventilated patients with left ventricular ejection fraction ≥ 30 %, immediately after elective coronary artery bypass grafting.

Methods

Prospective observational case series study including 35 patients with LVEF ≥ 30 %, undergoingelective coronary artery bypass grafting was conducted. Transthoracic echocardiography, passive leg raising and intravenous administration of saline were performed in all study subjects. Dynamic parameters derived from ultrasonographic assessment of the IVC diameter (collapsibility index–CI and distensibility index–DI), cardiac output

Results

There were 24 (68.57 %) responders in the study population. There were no statistical differences between the groups in relation to: clinical parameters, pre- and postoperative LVEF, fluid balance and CVP. Change in cardiac output after passive leg raising correlated significantly with that after the volume expansion (p=0.000, r=0.822). Dynamic IVC derivatives were slightly higher in fluid responders, however this trend did not reach statistical significance. None of the caval indices correlated with fluid responsiveness.

Conclusion

Dynamic IVC-derived parameters do not predict fluid responsiveness in mechanically ventilated patients with preserved ejection fraction immediately after elective coronary artery bypass grafting. Passive leg raising is not inferior to volume expansion in differentiating between fluid responders and nonresponders. Immediate fluid challenge after CABG is safe and well tolerated.

Electronic supplementary material

The online version of this article (doi:10.1186/s12947-016-0065-4) contains supplementary material, which is available to authorized users.

Postoperative Critical Care of the Adult Cardiac Surgical Patient. Part I: Routine Postoperative Care

OBJECTIVES

Cardiac surgery, including coronary artery bypass, cardiac valve, and aortic procedures, is among the most common surgical procedures performed in the United States. Successful outcomes after cardiac surgery depend on optimum postoperative critical care. The cardiac intensivist must have a comprehensive understanding of cardiopulmonary physiology and the sequelae of cardiopulmonary bypass. In this concise review, targeted at intensivists and surgeons, we discuss the routine management of the postoperative cardiac surgical patient.

DATA SOURCE AND SYNTHESIS

Narrative review of relevant English-language peer-reviewed medical literature.

CONCLUSIONS

Critical care of the cardiac surgical patient is a complex and dynamic endeavor. Adequate fluid resuscitation, appropriate inotropic support, attention to rewarming, and ventilator management are key components. Patient safety is enhanced by experienced personnel, a structured handover between the operating room and ICU teams, and appropriate transfusion strategies.

Clinical practice in perioperative monitoring in adult cardiac surgery: is there a standard of care? Results from an national survey

This study was to investigate and define what is considered as a current clinical practice in hemodynamic monitoring and vasoactive medication use after cardiac surgery in Italy. A 33-item questionnaire was sent to all intensive care units (ICUs) admitting patients after cardiac surgery. 71 out of 92 identified centers (77.2 %) returned a completed questionnaire. Electrocardiogram, invasive blood pressure, central venous pressure, pulse oximetry, diuresis, body temperature and blood gas analysis were identified as routinely used hemodynamic monitoring, whereas advanced monitoring was performed with pulmonary artery catheter or echocardiography. Crystalloids were the fluids of choice for volume replacement (86.8 % of Centers). To guide volume management, central venous pressure (26.7 %) and invasive blood pressure (19.7 %) were the most frequently used parameters. Dobutamine was the first choice for treatment of left heart dysfunction (40 %) and epinephrine was the first choice for right heart dysfunction (26.8 %). Half of the Centers had an internal protocol for vasoactive drugs administration. Intra-aortic balloon pump and extra-corporeal membrane oxygenation were widely available among Cardiothoracic ICUs. Angiotensin-converting enzyme inhibitors were suspended in 28 % of the Centers. The survey shows what is considered as standard monitoring in Italian Cardiac ICUs. Standard, routinely used monitoring consists of ECG, SpO2, etCO2, invasive BP, CVP, diuresis, body temperature, and BGA. It also shows that there is large variability among the various Centers regarding hemodynamic monitoring of fluid therapy and inotropes administration. Further research is required to better standardize and define the indicators to improve the standards of intensive care after cardiac surgery among Italian cardiac ICUs.

Bedside ultrasonographic measurement of the inferior vena cava fails to predict fluid responsiveness in the first 6 hours after cardiac surgery: a prospective case series observational study

OBJECTIVE

To assess validity of respiratory variation of inferior vena cava (IVC) diameter to predict fluid responsiveness and guide fluid therapy in mechanically ventilated patients during the first 6 hours after elective cardiac surgery.

DESIGN

Prospective observational case series study.

SETTING

Single-center hospital.

PATIENTS

50 consecutive patients undergoing elective cardiac surgery.

INTERVENTIONS

Transthoracic bedside echocardiography.

MEASUREMENTS AND MAIN RESULTS

Parameters derived from ultrasonographic assessment of the IVC diameter (collapsibility index [CI], distensibility index [DI], and IVC/aorta index). In the whole study group, change in fluid balance correlated with change in IVC maximum diameter (p = 0.034, r = 0.176). IVC-CI and IVC-DI correlated with IVC/aorta index. A weak correlation between central venous pressure (CVP) and IVC-derived parameters (IVC-CI and IVC-DI) was noticed. Despite statistical significance (p<0.05), all observed correlations expressed low statistical power (r<0.21). There were no statistically significant differences between fluid responders and nonresponders in relation to clinical parameters, CVP, ultrasound IVC measurement, and IVC-derived indices.

CONCLUSION

Dynamic IVC-derived parameters (IVC-CI, IVC-DI, and IVC/aorta index) and CVP are not reliable predictors of fluid responsiveness in the first 6 hours after cardiac surgery. Complexity of physiologic factors modulating cardiac performance in this group may be responsible for the difficulty in finding a plausible monitoring tool for fluid guidance. Bedside ultrasonographic measurement of IVC is unable to predict fluid responsiveness in the first 6 hours after cardiac surgery.

Positive inotropic agents in myocardial ischemia-reperfusion injury: a benefit/risk analysis

Positive inotropic agents should be used judiciously when managing surgical patients with acute myocardial ischemia–reperfusion injury, as use of these inotropes is not without potential adverse effects.

Ivabradine: potential clinical applications in critically ill patients

It has been extensively demonstrated that an elevated heart rate is a modifiable, independent risk factor for cardiovascular events. A high heart rate increases myocardial oxygen consumption and reduces diastolic perfusion time. It can also increase ventricular diastolic pressures and induce ventricular arrhythmias. Critical care patients are prone to develop a stress induced cardiac impairment and consequently an increase in sympathetic tone. This in turn increases heart rate. In this setting, however, heart rate lowering might be difficult because the effects of inotropic drugs could be hindered by heart rate reducing drugs like beta-blockers. Ivabradine is a new selective antagonist of funny channels. It lowers heart rate, reducing the diastolic depolarization slope. Moreover, ivabradine is not active on sympathetic pathways, thus avoiding any interference with inotropic amines. We reviewed the literature available regarding heart rate control in critical care patients, focusing our interest on the use of ivabradine to assess the potential benefits of the drug in this particular setting.

Goal-directed therapy in cardiac surgery: a systematic review and meta-analysis

BACKGROUND

Perioperative mortality after cardiac surgery has decreased in recent years although postoperative morbidity is still significant. Although there is evidence that perioperative goal-directed haemodynamic therapy (GDT) may reduce surgical mortality and morbidity in non-cardiac surgical patients, the data are less clear after cardiac surgery. The objective of this review is to perform a meta-analysis on the effects of perioperative GDT on mortality, morbidity, and length of hospital stay in cardiac surgical patients.

METHODS

We conducted a systematic review using Medline, EMBASE, and the Cochrane Controlled Clinical Trials Register. Additional sources were sought from experts. The inclusion criteria were randomized controlled trials, mortality reported as an outcome, pre-emptive haemodynamic intervention, and cardiac surgical population. Included studies were examined in full and subjected to quantifiable analysis, subgroup analysis, and sensitivity analysis where possible. Data synthesis was obtained by using odds ratio (OR) and mean difference (MD) for continuous data with 95% confidence interval (CI) utilizing a random-effects model.

RESULTS

From 4986 potential studies, 5 met all the inclusion criteria (699 patients). The quantitative analysis showed that the use of GDT reduced the postoperative complication rate (OR 0.33, 95% CI 0.15-0.73; P=0,006) and hospital length of stay (MD -2.44, 95% CI -4.03 to -0.84; P=0,003). There was no significant reduction in mortality.

CONCLUSION

The use of pre-emptive GDT in cardiac surgery reduces morbidity and hospital length of stay.

Preoperative NT-proBNP independently predicts outcome in patients with acute coronary syndrome undergoing CABG

OBJECTIVES

The predictive value of preoperative N-terminal pro-B-type natriuretic peptide (NT-proBNP) was evaluated in patients with acute coronary syndrome undergoing coronary artery bypass grafting (CABG).

DESIGN

As a substudy to a clinical trial 383 patients with acute coronary syndrome undergoing CABG were studied. 17 patients had a concomitant procedure. NT-proBNP was measured immediately preoperatively and evaluated with regard to in-hospital mortality, and severe circulatory failure postoperatively according to prespecified criteria. Follow-up was 3.2 ± 0.9 years.

RESULTS

In patients with isolated CABG, receiver operating characteristics (ROC) analysis showed an area under the curve (AUC) of 0.82 for in-hospital mortality and 0.87 for severe circulatory failure respectively with a best cut-off for preoperative NT-proBNP of 1028 ng/L. This cut-off level independently predicted severe circulatory failure. Patients with NT-proBNP < 1028 ng/L had significantly better long-term survival (p = 0.004). Preoperative NT-proBNP was higher in patients with concomitant procedure than isolated CABG (2146 ± 1858 v 887 ± 1635 ng/L; p = 0.0005). In patients with concomitant procedure ROC analysis showed an AUC of 0.93 for severe circulatory failure with a best cut-off for preoperative NT-proBNP of 3145 ng/L.

CONCLUSIONS

Preoperative NT-proBNP predicted in-hospital mortality, severe circulatory failure postoperatively and long-term survival in patients undergoing surgery for acute coronary syndrome but a higher threshold was found in patients having concomitant procedures.

Post cardiac surgery vasoplegia is associated with high preoperative copeptin plasma concentration

Introduction

Post cardiac surgery vasodilatation (PCSV) is possibly related to a vasopressin deficiency that could relate to chronic stimulation of adeno-hypophysis. To assess vasopressin system activation, a perioperative course of copeptin and vasopressin plasma concentrations were studied in consecutive patients operated on for cardiac surgery.

Methods

Sixty-four consecutive patients scheduled for elective cardiac surgery with cardiopulmonary bypass were studied. Hemodynamic, laboratory and clinical data were recorded before and during cardiopulmonary bypass, and at the eighth postoperative hour (H8). At the same time, blood was withdrawn to determine plasma concentrations of arginine vasopressin (AVP, radioimmunoassay) and copeptin (immunoluminometric assay). PCSV was defined as mean arterial blood pressure < 60 mmHg with cardiac index ≥ 2.2 l/min/m², and was treated with norepinephrine to restore mean blood pressure > 60 mmHg. Patients with PCSV were compared with the other patients (controls). Student's t test, Fisher's exact test, or nonparametric tests (Mann-Whitney, Wilcoxon) were used when appropriate. Correlation between AVP and copeptin was evaluated and receiver-operator characteristic analysis assessed the utility of preoperative copeptin to distinguish between controls and PCSV patients.

Results

Patients who experienced PCSV had significantly higher copeptin plasma concentration before cardiopulmonary bypass (P < 0.001) but lower AVP concentrations at H8 (P < 0.01) than controls. PCSV patients had preoperative hyponatremia and decreased left ventricle ejection fraction, and experienced more complex surgery (redo). The area under the receiver-operator characteristic curve of preoperative copeptin concentration was 0.86 ± 0.04 (95% confidence interval = 0.78 to 0.94; P < 0.001). The best predictive value for preoperative copeptin plasma concentration was 9.43 pmol/l with a sensitivity of 90% and a specificity of 77%.

Conclusions

High preoperative copeptin plasma concentration is predictive of PSCV and suggests an activation of the AVP system before surgery that may facilitate depletion of endogenous AVP stores and a relative AVP deficit after surgery.

The relationship between inotrope exposure, six-hour postoperative physiological variables, hospital mortality and renal dysfunction in patients undergoing cardiac surgery

Introduction

Acute haemodynamic complications are common after cardiac surgery and optimal perioperative use of inotropic agents, typically guided by haemodynamic variables, remains controversial. The aim of this study was to examine the relationship of inotrope use to hospital mortality and renal dysfunction.

Material and methods

A retrospective cohort study of 1,326 cardiac surgery patients was carried out at two university-affiliated ICUs. Multivariable logistic regression analysis and propensity matching were performed to evaluate whether inotrope exposure was independently associated with mortality and renal dysfunction.

Results

Patients exposed to inotropes had a higher mortality rate than those not exposed. After adjusting for differences in Parsonnet score, left ventricular ejection fraction, perioperative intraaortic balloon pump use, bypass time, reoperation and cardiac index, inotrope exposure appeared to be independently associated with increased hospital mortality (adjusted odds ratio (OR) 2.3, 95% confidence interval (95% CI) 1.2 to 4.5) and renal dysfunction (adjusted OR 2.7, 95% CI 1.5 to 4.6). A propensity score-matched analysis similarly demonstrated that death and renal dysfunction were significantly more likely to occur in patients exposed to inotropes (P = 0.01).

Conclusions

Postoperative inotrope exposure was independently associated with worse outcomes in this cohort study. Further research is needed to better elucidate the appropriate use of inotropes in cardiac surgery.

Local epicardial inotropic drug delivery allows targeted pharmacologic intervention with preservation of myocardial loading conditions

Local myocardial application of inotropes may allow the study of pharmacologically augmented central myocardial contraction in the absence of confounding peripheral vasodilating effects and alterations in heart loading conditions. Novel alginate epicardial (EC) drug releasing platforms were used to deliver dobutamine to the left ventricle of rats. Pressure-volume analyses indicated that although both local and systemic intravenous (i.v.) use of inotropic drugs increase stroke volume and contractility, systemic infusion does so through heart unloading. Conversely, EC application preserves heart load and systemic blood pressure. EC dobutamine increased indices of contractility with minimal rise in heart rate and lower reduction in systemic vascular resistance than i.v. infusion. Drug sampling showed that dobutamine concentration was 650-fold higher in the anterior wall than in the inferior wall. The plasma dobutamine concentration with local delivery was about half as much as with systemic infusion. These data suggest that inotropic EC delivery has a localized effect and augments myocardial contraction by different mechanisms than systemic infusion, with far fewer side effects. These studies demonstrate a pharmacologic paradigm that may improve heart function without interference from effects on the vasculature, alterations in heart loading, and may ultimately improve the health of heart failure patients.

Automated Cardiac Drug Infusion System Using Adaptive Fuzzy Neural Networks Controller

This paper presents a fuzzy neural network (FNN) control system to automatically manage the hemodynamic variables of patients with hypertension and congestive heart failure (CHF) via simultaneous infusion of cardiac drugs such as vasodilators and inotropic agents. The developed system includes two FNN sub-controllers for regulating cardiac output (CO) and mean arterial pressure (MAP) by cardiac drugs, considering interactive pharmacological effects. The adaptive FNN controller was tested and evaluated on a cardiovascular model. Six short-term therapy conditions of hypertension and CHF are presented under different sensitivities of a vasodilator drug. The results of the automated system showed that root mean square errors were ≤ 5.56 mmHg and ≤ 0.22 L min-1 for regulating MAP and CO, respectively, providing short settling time responses of MAP (≤ 10.9 min) and CO (≤ 8.22 min) in all therapy conditions. The proposed FNN control scheme can significantly improve the performance of cardiac drug infusion System.

Evaluation of dexmedetomidine versus propofol-based sedation therapy in mechanically ventilated cardiac surgery patients at a tertiary academic medical center

Management of pain and sedation therapy is a vital component of optimizing patient outcomes; however, the ideal pharmacotherapy regimen has not been identified in the postoperative cardiac surgery population. We sought to evaluate efficacy and safety outcomes between postoperative mechanically ventilated cardiac surgery patients receiving dexmedetomidine versus propofol therapy upon arrival to the intensive care unit (ICU). We conducted a single center, descriptive study of clinical practice at a 20-bed cardiac surgery ICU in a tertiary academic medical center. Adult mechanically ventilated postcardiac surgery patients who received either dexmedetomidine or propofol for sedation therapy upon admission to the ICU between October 20, 2006 and December 15, 2006 were evaluated. A pharmacy database was used to identify patients receiving dexmedetomidine or propofol therapy for perioperative sedation during cardiac surgery. Patients were matched according to surgical procedure type. Fifty-six patients who received either dexmedetomidine (n = 28) or propofol (n = 28) were included in the analysis. No differences in the ICU length of stay (58.67 ± 32.61 vs. 61 ± 33.1 hours; P = 0.79) and duration of mechanical ventilation (16.21 ± 6.05 vs. 13.97 ± 4.62 hours; P = 0.13) were seen between the propofol and dexmedetomidine groups, respectively. Hypotension (17 [61%] vs. 9 [32%]; P = 0.04), morphine use (11 [39.3%] vs. 1 [3.6%]; P = 0.002), and nonsteroidal anti-inflammatory use (7 [25%] vs. 1 [3.6%]; P = 0.05) occurred more during dexmedetomidine therapy versus propofol. Dexmedetomidine therapy resulted in a higher incidence of hypotension and analgesic consumption compared with propofol-based sedation therapy. Further evaluation is needed to assess differences in clinical outcomes of propofol and dexmedetomidine-based therapy in mechanically ventilated cardiac surgery patients.

Inadequate visualization and reporting of ventricular function from transthoracic echocardiography after cardiac surgery

OBJECTIVES

The purpose of this study was to determine the incidence of and risk factors for inadequate reporting of ventricular function from transthoracic echocardiography after cardiac surgery.

DESIGN AND SETTING

A retrospective study of cardiac surgical patients at 1 university hospital.

PATIENTS

The first 300 consecutive patients who had transthoracic echocardiogram within the first 7 days after cardiac surgery.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The primary outcomes for this study were inadequate visualization of the left ventricle, the right ventricle, or both ventricles. Analysis of data from 300 patients identified inadequate imaging of the left ventricle in 50 (17%) cases, inadequate imaging of the right ventricle in 112 (37%) cases, inadequate imaging of both ventricles in 37 (12%) cases, and inadequate imaging of either the left or right ventricle in 125 (42%) cases. Increasing age, earlier postoperative day, male sex, and median sternotomy were associated with inadequate imaging.

CONCLUSIONS

Transthoracic imaging is often inadequate in patients who have undergone recent cardiac surgery. Patient and surgical characteristics influence reporting of right and left ventricular function.

The vasopressin and copeptin response in patients with vasodilatory shock after cardiac surgery: a prospective, controlled study

OBJECTIVE

To evaluate arginine vasopressin (AVP) and copeptin plasma concentrations in patients with vasodilatory shock after cardiac surgery.

DESIGN

Prospective, controlled, clinical study.

SETTING

Surgical intensive care unit and cardiac surgery ward in a tertiary university teaching hospital.

PATIENTS AND PARTICIPANTS

Thirty-three critically ill patients with vasodilatory shock after cardiac surgery and ten control patients undergoing uncomplicated aorto-coronary bypass surgery.

MEASUREMENTS AND RESULTS

Hemodynamic, laboratory and clinical data were recorded daily in all patients during the first 7 days after cardiac surgery. At the same time, points blood was withdrawn to determine plasma concentrations of AVP (radioimmunoassay) and copeptin (immunoluminometric assy). Standard tests, a mixed effects model and regression analyses were used for statistical analysis. The course of AVP was significantly different between groups (P < 0.001). While AVP concentrations were lower in the study group on the first postoperative day, they were higher than that in the control group from postoperative day 3 on. There was no difference in the postoperative AVP response between study patients with or without chronic angiotensin-converting enzyme inhibitor therapy. Except during continuous veno-venous hemofiltration, AVP and copeptin correlated significantly with each other (P < 0.001; r = 0.749).

CONCLUSIONS

The AVP response to cardiac surgery is significantly different between patients with vasodilatory shock and patients undergoing uncomplicated aorto-coronary bypass surgery. Although no causative relationship between AVP concentrations and cardiovascular instability can be drawn from these results, our data support the hypothesis that inadequately low AVP plasma levels contribute to the failure to restore vascular tone in vasodilatory shock after cardiac surgery.

Pharmacologic management of the postoperative cardiac surgery patient

Maintaining adequate cardiac output in postoperative cardiac surgery patients is a complex and challenging feat for health care teams. Alterations in preload, afterload, contractility, heart rate, and rhythm can be devastating to these patients and lead to lethal consequences. An array of pharmacologic therapies is available in the critical care setting to help prevent and treat such complications and ensure satisfactory cardiac performance.

Trends in cardiac surgery: exploring the past and looking into the future

Today's successes would not be possible without the foundation of yesterday's practitioners and patients. This article assists in the exploration of cardiac surgery procedures, provides a brief historical review of the significant changes in cardiothoracic surgery, and provides an overview of current and future methods of treatment for coronary revascularization and heart failure. It is difficult for one article to encompass all aspects of cardiothoracic surgery. This article highlights many of the transforming moments that have led us to where we are today and explores the current trends of cardiac surgery and possibilities for tomorrow.