Diastolic heart failure in anaesthesia and critical care

Effect of Sevoflurane Anesthesia on Diastolic Function: A Prospective Observational Study

BACKGROUND

The effect of sevoflurane on left ventricular diastolic function is not well understood. We hypothesized that parameters of diastolic function may improve under sevoflurane anesthesia in patients with preexisting diastolic dysfunction compared to patients with normal diastolic function.

METHODS

This observational study included 60 patients undergoing breast surgery or laparoscopic cholecystectomy. Patients were assigned to diastolic dysfunction (n = 34) or normal (n = 26) groups of septal e' < 8 or ≥ 8.0 cm/s on the first thoracic echocardiography (TTE) performed before anesthesia. During anesthesia, sevoflurane was maintained at 1 to 2 minimum alveolar concentration (MAC) to maintain the bispectral index at 40 to 50. At the end of surgery, the second TTE was performed under 0.8 to 1 MAC of sevoflurane with the patient breathing spontaneously without ventilator support. Primary end point was the percentage change (Δ) of e' on 2 TTEs (Δe'). Secondary end points were ΔE/e', Δleft atrial volume index (ΔLAVI), and Δtricuspid regurgitation maximum velocity (ΔTR Vmax). These percentage changes (Δ) were compared between diastolic dysfunction and normal groups.

RESULTS

e' (Δe': 30 [6, 64] vs 0 [-18, 11]%; P < .001), mitral inflow E wave velocity (E), mitral inflow E/A ratio (E/A), and mitral E velocity deceleration time (DT) improved significantly in diastolic dysfunction group compared to normal group. LAVI decreased in diastolic dysfunction group but did not reach statistical significance between the 2 groups (ΔLAVI:-15 [-31, -3] vs -4 [-20, 10]%, P = .091). ΔE/e' was not different between the 2 groups (11 [-16, 26] vs 12 [-9, 22]%, P = .853) (all: median [interquartile range, IQR]). TR was minimal in both groups.

CONCLUSIONS

In this study, echocardiographic parameters of diastolic function, including septal e', E, E/A, and DT, improved with sevoflurane anesthesia in patients with preexisting diastolic dysfunction, but remained unchanged in patients with normal diastolic function.

The value of a dynamic echocardiographic approach to diastolic dysfunction in intensive care medicine

Diastolic dysfunction is an underestimated feature in the context of the critically ill setting and perioperative medicine. Advances in echocardiography, its noninvasive, safe and easy use, have allowed Doppler echocardiography to become a cornerstone for diagnosing diastolic dysfunction in clinical practice. The diagnosis of diastolic dysfunction and increased filling pressures is nevertheless complex. Using an echocardiographic assessment and the routine application of preload stress maneuvers during echocardiographic examination can help identify early stages of diastolic dysfunction leading to better management of patients at risk of acute heart decompensation in the perioperative period or during ICU stay.

Pre-operative point-of-care assessment of left ventricular diastolic dysfunction, an observational study

BACKGROUND

Left ventricular (LV) diastolic dysfunction is an acknowledged peri-operative risk factor that should be identified before surgery. This study aimed to evaluate a simplified echocardiographic method using e' and E/e' for identification and grading of diastolic dysfunction pre-operatively.

METHODS

Ninety six ambulatory surgical patients were consecutively included to this prospective observational study. Pre-operative transthoracic echocardiography was conducted prior to surgery, and diagnosis of LV diastolic dysfunction was established by comprehensive and simplified assessment, and the results were compared. The accuracy of e'-velocities in order to discriminate patients with diastolic dysfunction was established by calculating accuracy, efficiency, positive (PPV) and negative predictive (NPV) values, and area under the receiver operating characteristic curve (AUROC).

RESULTS

Comprehensive assessment established diastolic dysfunction in 77% (74/96) of patients. Of these, 22/74 was categorized as mild dysfunction, 43/74 as moderate dysfunction and 9/74 as severe dysfunction. Using the simplified method with e' and E/e', diastolic dysfunction was established in 70.8% (68/96) of patients. Of these, 8/68 was categorized as mild dysfunction, 36/68 as moderate dysfunction and 24/68 as severe dysfunction. To discriminate diastolic dysfunction of any grade, e'-velocities (mean < 9 cm s^- 1) had an AUROC of 0.901 (95%CI 0.840-0.962), with a PPV of 55.2%, a NPV of 90.9% and a test efficiency of 0.78.

CONCLUSIONS

The results of this study indicate that a simplified approach with tissue Doppler e'-velocities may be used to rule out patients with diastolic dysfunction pre-operatively, but together with E/e' ratio the severity of diastolic dysfunction may be overestimated.

TRIAL REGISTRATION

Clinicaltrials.gov, Identifier: NCT03349593 . Date of registration 21/11/2017. https://clinicaltrials.gov .

Polymorphic Variants in the GRK5 Gene Promoter Are Associated With Diastolic Dysfunction in Coronary Artery Bypass Graft Surgery Patients

BACKGROUND

The G-protein-coupled receptor kinase 5 (GRK5) is a mediator of cardiovascular homeostasis and participates in inflammation and cardiac fibrosis, both being involved in the development of diastolic dysfunction (DD). While mechanisms of transcriptional regulation of the GRK5 promoter are unclear, we tested the hypotheses, that (1) GRK5 expression varies depending on functional single nucleotide polymorphisms (SNPs) in the GRK5 promoter and (2) this is associated with DD in patients undergoing coronary artery bypass graft (CABG) surgery.

METHODS

We amplified and sequenced the GRK5 promoter followed by cloning, reporter assays, and electrophoretic mobility shift assays (EMSA). GRK5 messenger ribonucleic acid (mRNA) expression was determined in right atrial tissue sampled from 50 patients undergoing CABG surgery. In another prospective study, GRK5 genotypes were associated with determinants of diastolic function using transesophageal echocardiography in 255 patients with CABG with normal systolic left ventricular (LV) function. Specifically, we measured ejection fraction (EF), transmitral Doppler early filling velocity (E), tissue Doppler early diastolic lateral mitral annular velocity (E' lateral), and calculated E/E', E' norm and the difference of E' lateral and E' norm to account for age-related changes in diastolic function.

RESULTS

We identified 6 SNPs creating 3 novel haplotypes with the greatest promoter activation in haplotype tagging (ht) SNP T(-678)C T-allele constructs (P < .001). EMSAs showed allele-specific transcription factor binding proving functional activity. GRK5 mRNA expression was greatest in TT genotypes (TT: 131 fg/µg [95% CI, 108-154]; CT: 109 [95% confidence interval {CI}, 93-124]; CC: 83 [95% CI, 54-112]; P = .012). Moreover, GRK5 genotypes were significantly associated with determinants of diastolic function. Grading of DD revealed more grade 3 patients in TT compared to CT and CC genotypes (58% vs 38% vs 4%; P = .023). E´ lateral was lowest in TT genotypes (P = .007) and corresponding E/E' measurements showed 1.27-fold increased values in TT versus CC genotypes (P = .01), respectively. While E' norm values were not different between genotypes (P = .182), the difference between E' lateral and E' norm was significantly higher in TT genotypes compared to CC and CT genotypes (-1.2 [interquartile range {IQR}, 2.7], -0.5 [IQR, 3.4], and -0.4 [IQR, 4.2; P = .035], respectively).

CONCLUSIONS

A functional GRK5 SNP results in allele-dependent differences in GRK5 promoter activity and mRNA expression. This is associated with altered echocardiographic determinants of diastolic function. Thus, SNPs in the GRK5 promoter are associated with altered perioperative diastolic cardiac function. In the future, preoperative testing for these and other SNPs might allow to initiate more specific diagnostic and perioperative pathways to benefit patients at risk.

Pre-operative transthoracic echocardiography in ambulatory surgery-A cross-sectional study

BACKGROUND

Cardiac disease and aberrations in central volume status are risk factors for perioperative complications, and should be identified prior to surgery. This study investigated the benefit of transthoracic echocardiography (TTE) for pre-operative identification of cardiac disease and hypovolemia in ambulatory surgery.

METHODS

Ninety-six patients, with a mean age of 63.5 ± 12.2 years and body mass index of 27.0 ± 4.3 kg/m² , scheduled for ambulatory surgery (breast, thyroid, and minor gastrointestinal), were consecutively enrolled in this prospective observational study. Pre-operative comprehensive TTE was performed in order to assess heart failure (HF), asymptomatic left ventricular dysfunction, valvular disease, and aberrations in central volume status.

RESULTS

Pre-operative TTE identified a total of 28 cases of HF, 13 cases of HF with reduced or moderately reduced, ejection fraction (EF), and 15 cases of HF with preserved EF. Furthermore, 46 cases of asymptomatic left ventricular (LV) dysfunction were identified. 44/96 patients were hypovolemic, 16 of whom in severe hypovolemia. Seven cases of previously unknown obstructive valvular or myocardial disease and six cases of right ventricular systolic dysfunction were identified. A total of 24% (23/96) were classified as potential critical hemodynamic findings. The number needed (NNT) to treat for pre-operative TTE in order to find one critical finding was 4.2.

CONCLUSION

In this ambulatory surgical cohort, a high prevalence of pre-operative LV dysfunction and aberrations in volume status was observed. The results demonstrate that pre-operative TTE contributed valuable hemodynamic information. The standard pre-operative assessment for this cohort might need to be revised.

Anesthetic management of women with heart failure during pregnancy: a retrospective cohort study

BACKGROUND

The incidence of heart failure among pregnant women with pre-existing cardiac disease is quoted as 13%, with 10% requiring hospitalization. There is limited literature on heart failure in the pregnant population. The study objective was to describe the etiology and management of women hospitalized in our institution for heart failure during pregnancy.

METHODS

A retrospective cohort study investigated women who presented with heart failure in pregnancy between 2004 and 2017. Hospital records were interrogated using International Classification of Diseases v10 codes for heart failure. Patient characteristics, investigations, treatment, obstetric and anesthetic management, and maternal-fetal outcome data were collected and summarized using descriptive statistics.

RESULTS

One-hundred-and-twenty cases (in 93 122 deliveries) were identified across the 13-year period (antepartum heart failure 51%, postpartum heart failure 49%).The most common etiologies were pre-eclampsia (28%), cardiomyopathy (22%), and valvular heart disease (18%). Cesarean delivery occurred in 76% of cases (13% because of the maternal cardiac condition). Neuraxial techniques were used for most deliveries (cesarean 83%; vaginal 90%). For cesarean delivery, titrated epidural or general anesthesia was employed in 48% and 16%, respectively. Cardiac arrest occurred in two cases (1.7%) and 44% required coronary or intensive care unit admission.

CONCLUSIONS

The incidence of heart failure was 0.13% (1:776 deliveries). Pre-eclampsia was the leading cause but may have been historically under-acknowledged. Anesthetic and obstetrical decisions were tailored by means of multidisciplinary input, with cesarean delivery and regional anesthesia used in the majority. The postpartum period warrants heightened attention for these patients.

Diastolic dysfunction of the left ventricle - a practical approach for an anaesthetist

Bedside point-of-care echocardiography is being increasingly incorporated in peri-operative assessment and in intensive care units. Because of availability of tissue Doppler imaging in the modern ultrasound machines there has been an increased interest in research of diastolic function of left ventricle. The diastolic function is crucial for the hemodynamically effective function of the heart. Diastolic dysfunction is a well-established risk factor of the major adverse cardiac events during perioperative period, complications during weaning from ventilator and prognostic factor of mortality in septic shock.

Effect of preoperative fluid therapy on hemodynamic stability during anesthesia induction, a randomized study

BACKGROUND

Preserving perfusion pressure during anesthesia induction is crucial. Standardized anesthesia methods, alert fluid therapy and vasoactive drugs may help maintain adequate hemodynamic conditions throughout the induction procedure. In this randomized study, we hypothesized that a pre-operative volume bolus based on lean body weight would decrease the incidence of significant blood pressure drops (BPD) after induction with target-controlled infusion (TCI) or rapid sequence induction (RSI).

METHODS

Eighty individuals scheduled for non-cardiac surgery were randomized to either a pre-operative colloid fluid bolus of 6 ml kg^-1 lean body weight or no bolus, and then anesthetized by means of TCI or RSI. The main outcome measure was blood pressure drops below the mean arterial pressure 65 mm Hg during the first 20 minutes after anesthesia induction. ClinicalTrials.com Identifier: NCT03394833.

RESULTS

Pre-operative fluid therapy decreased the incidence of BPDs fivefold, from 23 of 40 (57.5%) individuals without fluids to 5 of 40 (12.5%) with fluid management, P < .001. The mean BPD was greater in the groups without pre-operative fluids compared to the groups with fluid management; 53 ± 18 mm Hg vs 43 ± 14 mm Hg, P = .007. The overall mean volume of pre-operative fluid bolus infused was 387 ± 52 ml. There was no difference in hemodynamic stability between TCI and RSI. No correlation was shown between incidence of BPDs and increasing age, medication, hypertension, diabetes, renal failure, or low physical capacity.

CONCLUSIONS

Pre-operative fluid bolus decreased the incidence of significant blood pressure drops during TCI and RSI induction of general anesthesia.

Évaluation de la fonction diastolique du ventricule gauche en réanimation pédiatrique : quelles indications, quels paramètres mesurer ?

L’incidence des patients avec une insuffisance cardiaque diastolique a augmenté au cours des dernières années. De nombreuses études épidémiologiques, physiopathologiques, cliniques ou pronostiques ont été menées pour comprendre cette nouvelle entité. L’étude et l’analyse de la fonction diastolique (FD) sont devenues des temps essentiels de l’examen échocardiographique. Cet article a pour objectifs : 1) de faire le point sur la physiologie de la FD du ventricule gauche (VG) et sur son évaluation chez l’enfant ; 2) d’envisager des applications cliniques en réanimation pédiatrique pour lesquelles son évaluation est importante. L’évaluation de la FD du VG est complexe, en plein essor et encore peu réalisée en pédiatrie. De plus, la tachycardie chez l’enfant et les particularités pédiatriques encore méconnues rendent difficile l’analyse de certains paramètres. L’ETT est l’examen complémentaire incontournable pour évaluer la FD du VG, mais en cours d’étude chez l’enfant. L’évaluation de la FD du VG devrait faire partie intégrante des paramètres échocardiographiques à prendre en considération pour certaines situations (évaluation de la réponse au remplissage vasculaire et de la sevrabilité à la ventilation mécanique, ajustement des traitements…) afin de mieux comprendre sa mesure et l’utiliser en routine clinique. On retiendra que pour l’évaluation échocardiographique chez l’enfant de réanimation : dans un premier temps évaluer la fonction systolique puis s’efforcer d’évaluer l’évolution de la FD par les pressions de remplissage par des paramètres simples (doppler mitral et tissulaire) ajustés au Z-score (urihttp://www.parameterz.comhttp://www.parameterz.com) tels que les rapports E/e’ et E/A, le volume indexé de l’OG, le tout assorti au contexte clinique et à la cinétique des paramètres biologiques (BNP, NT pro-BNP).

Preliminary Exploration of Epidemiologic and Hemodynamic Characteristics of Restrictive Filling Diastolic Dysfunction Based on Echocardiography in Critically Ill Patients: A Retrospective Study

Objective

To preliminarily describe the epidemiologic and hemodynamic characteristics of critically ill patients with restrictive filling diastolic dysfunction based on echocardiography.

Setting

A retrospective study.

Methods

Epidemiologic characteristics of patients with restrictive filling diastolic dysfunction in ICU were described; clinical and hemodynamic data were preliminarily summarized and compared between patients with and without restrictive filling diastolic dysfunction; most of the data were based on echocardiography.

Results

More than half of the patients in ICU had diastolic dysfunction and about 16% of them had restrictive filling pattern. The patients who had restrictive filling diastolic dysfunction were more likely to have wider diameter of IVC (2.18 ± 0.50 versus 1.92 ± 0.43, P = 0.037), higher extravascular lung water score (15.9 ± 9.2 versus 13.2 ± 9.1, P = 0.014), lower left ventricular ejection fraction (EF-S: 53.0 ± 16.3 versus 59.3 ± 12.5, P = 0.014), and lower percentage of normal LAP that was estimated by E/e′ (8.9% versus 90.0%, P = 0.001) when compared with those of patients without restrictive filling diastolic dysfunction.

Conclusion

Our results suggest that critically ill patients with restrictive filling diastolic dysfunction may experience rising volume status, increasing extravascular lung water ultrasonic score, reducing long-axis systolic dysfunction, and less possibility of normal left atrial pressure. Intensivists are advised to pay more attention to patients with diastolic dysfunction, especially the exquisite fluid management of patients with restrictive filling pattern due to the close relationship of restrictive filling diastolic dysfunction with volume status and extravascular lung water in our study.

Pulmonary Edema and Diastolic Heart Failure in the Perioperative Period

Heart failure with preserved ejection fraction (HFPEF) is a diagnosis encountered with increasing frequency in the aging population. We present a case of postoperative pulmonary edema in 63-year-old male with HFPEF. This patient highlights the gap in risk stratification with respect to diastolic heart failure.

A case study of likely wild-type cardiac transthyretin amyloidosis causing rapid deterioration

We present the case of an 88-year-old gentleman who presented to hospital septic with bilateral leg cellulitis, pulmonary oedema and hypotension. He had no history of heart disease but had had bilateral carpal tunnel releases. His condition deteriorated with refractory hypotension in spite of fluid filling, inotropic and vasopressor support. His echocardiogram showed an infiltrative cardiomyopathy with a speckled myocardium, severe concentric left and right ventricular increased wall thickness, diastolic dysfunction, biatrial dilatation and restrictive physiology in keeping with cardiac amyloidosis. He developed atrial fibrillation and worsening respiratory failure due to fluid overload and was intubated and ventilated but continued to decline and passed away. The degree of heart failure in the absence of ischaemia, the patient's advanced age, echocardiographic findings and past history of carpal tunnel syndrome in a male are strongly indicative of a diagnosis of wild-type cardiac transthyretin amyloidosis. We discuss the key features and intensive care management of this disease.

Perioperative management of left ventricular diastolic dysfunction and heart failure: an anesthesiologist's perspective

Anesthesiologists frequently see asymptomatic patients with diastolic dysfunction or heart failure for various surgeries. These patients typically show normal systolic function but abnormal diastolic parameters in their preoperative echocardiographic evaluations. The symptoms that are sometimes seen are similar to those of chronic obstructive pulmonary disease. Patients with diastolic dysfunction, and even with diastolic heart failure, have the potential to develop a hypertensive crisis or pulmonary congestion. Thus, in addition to conventional perioperative risk quantification, it may be important to consider the results of diastolic assessment for predicting the postoperative outcome and making better decisions. If anesthesiologists see female patients older than 70 years of age who have hypertension, diabetes, chronic renal disease, recent weight gain, or exercise intolerance, they should focus on the patient's diastologic echocardiography indicators such as left atrial enlargement or left ventricular hypertrophy. In addition, there is a need for perioperative strategies to mitigate diastolic dysfunction-related morbidity. Specifically, hypertension should be controlled, keeping pulse pressure below diastolic blood pressure, maintaining a sinus rhythm and normovolemia, and avoiding tachycardia and myocardial ischemia. There is no need to classify these diastolic dysfunction, but it is important to manage this condition to avoid worsening outcomes.

The effect of perioperative insulin treatment on cardiodepression in mild adiposity in mice

Background

While most studies focus on cardiovascular morbidity following anesthesia and surgery in excessive obesity, it is unknown whether these intraoperative cardiovascular alterations also occur in milder forms of adiposity without type 2 diabetes and if insulin is a possible treatment to improve intraoperative myocardial performance. In this experimental study we investigated whether mild adiposity without metabolic alterations is already associated with cardiometabolic dysfunction during anesthesia, mechanical ventilation and surgery and whether these myocardial alterations can be neutralized by intraoperative insulin treatment.

Methods

Mice were fed a western (WD) or control diet (CD) for 4 weeks. After metabolic profiling, mice underwent general anesthesia, mechanical ventilation and surgery. Cardiac function was determined with echocardiography and left-ventricular pressure–volume analysis. Myocardial perfusion was determined with contrast-enhanced echocardiography. WD-fed mice were subsequently treated with insulin by hyperinsulinemic euglycemic clamping followed by the same measurements of cardiac function and perfusion.

Results

Western-type diet feeding led to a 13 % increase in bodyweight, (p < 0.0001) and increased adipose tissue mass, without metabolic alterations. Despite this mild phenotype, WD-fed mice had decreased systolic and diastolic function (end-systolic elastance was 2.0 ± 0.5 versus 4.1 ± 2.4 mmHg/μL, p = 0.01 and diastolic beta was 0.07 ± 0.03 versus 0.04 ± 0.01 mmHg/μL, p = 0.02) compared to CD-fed mice. Ventriculo-arterial coupling and myocardial perfusion were decreased by 48 % (p = 0.003) and 43 % (p = 0.03) respectively. Insulin treatment in WD-fed mice improved echo-derived systolic function (fractional shortening 42 ± 5 % to 46 ± 3, p = 0.05), likely due to decreased afterload, but there was no effect on load-independent measures of systolic function or myocardial perfusion. However, there was a trend towards improved diastolic function after insulin treatment (43 % improvement, p = 0.05) in WD-fed mice.

Conclusions

Mild adiposity without metabolic alterations already affected cardiac function and perfusion during anesthesia, mechanical ventilation and surgery in mice. Intraoperative insulin may be beneficial to reduce afterload and enhance intraoperative ventricular relaxation, but not to improve ventricular contractility or myocardial perfusion.

Diastolic dysfunction in the critically ill patient

Left ventricular diastolic dysfunction is a common finding in critically ill patients. It is characterized by a progressive deterioration of the relaxation and the compliance of the left ventricle. Two-dimensional and Doppler echocardiography is a cornerstone in its diagnosis. Acute pulmonary edema associated with hypertensive crisis is the most frequent presentation of diastolic dysfunction critically ill patients. Myocardial ischemia, sepsis and weaning failure from mechanical ventilation also may be associated with diastolic dysfunction. The treatment is based on the reduction of pulmonary congestion and left ventricular filling pressures. Some studies have found a prognostic role of diastolic dysfunction in some diseases such as sepsis. The present review aims to analyze thoroughly the echocardiographic diagnosis and the most frequent scenarios in critically ill patients in whom diastolic dysfunction plays a key role.

Comparison of dexmedetomidine with fentanyl for maintenance of intraoperative hemodynamics in hypertensive patients undergoing major surgery: A randomized controlled trial

Background:

The objective of this study was to study and compare the effects of intravenous dexmedetomidine and fentanyl on intraoperative hemodynamics, opioid consumption, and recovery characteristics in hypertensive patients.

Methods:

Fifty-seven hypertensive patients undergoing major surgery were randomized into two groups, Group D (dexmedetomidine, n = 29) and Group F (fentanyl, n = 28). The patients received 1 μg/kg of either dexmedetomidine or fentanyl, followed by 0.5 μg/kg/h infusion of the same drug, followed by a standard induction protocol. Heart rate (HR), mean arterial pressures (MAPs), end-tidal isoflurane concentration, and use of additional fentanyl and vasopressors were recorded throughout.

Results:

Both dexmedetomidine and fentanyl caused significant fall in HR and MAP after induction and dexmedetomidine significantly reduced the induction dose of thiopentone (P = 0.026). After laryngoscopy and intubation, patients in Group D experienced a fall in HR and a small rise in MAP (P = 0.094) while those in Group F showed significant rise in HR (P = 0.01) and MAP (P = 0.004). The requirement of isoflurane and fentanyl boluses was significantly less in Group D. The duration of postoperative analgesia was longer in Group D (P = 0.015) with significantly lower postoperative nausea and vomiting (PONV) (P < 0.001).

Conclusion:

Infusion of dexmedetomidine in hypertensive patients controlled the sympathetic stress response better than fentanyl and provided stable intraoperative hemodynamics. It reduced the dose of thiopentone, requirement of isoflurane and fentanyl boluses. The postoperative analgesia was prolonged, and incidence of PONV was less in patients who received dexmedetomidine.

Reversible Cardiomyopathies

Cardiomyopathies (CMs) have many etiological factors that can result in severe structural and functional dysregulation. Fortunately, there are several potentially reversible CMs that are known to improve when the root etiological factor is addressed. In this article, we discuss several of these reversible CMs, including tachycardia-induced, peripartum, inflammatory, hyperthyroidism, Takotsubo, and chronic illness-induced CMs. Our discussion also includes a review on their respective pathophysiology, as well as possible management solutions.

[Perioperative care of patients with diastolic heart failure. Interface to anesthesia]

Diastolic heart failure leads to an increase in perioperative morbidity and mortality. The prevalence of this disease is rising and multiple risk factors have already been identified. Besides higher age and female gender, arterial hypertension, diabetes mellitus and coronary artery disease in particular have to be considered. Clinical examination and laboratory analyses are important for preoperative evaluation; however, echocardiography plays the most important role in the diagnostics of diastolic heart failure. The transmitral flow profile can be used to differentiate the grades of diastolic dysfunction using the ratio between early passive ventricular filling (E) and late active filling due to atrial contraction (A). Data concerning the ideal anesthesia technique are for the most part lacking; however, the application of thoracic epidural anesthesia seems to be beneficial. A great deal of attention has to be paid to the intraoperative volume status of patients with diastolic dysfunction as hypovolemia and hypervolemia can both have detrimental effects. Arrhythmias and major changes in blood pressure put this special group of patients at additional risks.

Routine pre-operative focused ultrasonography by anesthesiologists in patients undergoing urgent surgical procedures

BACKGROUND

Unexpected cardiopulmonary complications are well described during surgery and anesthesia. Pre-operative evaluation by focused cardiopulmonary ultrasonography may prevent such mishaps. The aim of this study was to determine the frequency of unexpected cardiopulmonary pathology with focused ultrasonography in patients undergoing urgent surgical procedures.

METHODS

We performed pre-operative focused cardiopulmonary ultrasonography in patients aged 18 years or above undergoing urgent surgical procedures at pre-defined study days. Known and unexpected cardiopulmonary pathology was recorded, and subsequent changes in the anesthesia technique or supportive actions were registered.

RESULTS

A total of 112 patients scheduled for urgent surgical procedures were included. Their mean age (standard deviation) was 62 (21) years. Of these patients, 24% were American Society of Anesthesiologists (ASA) class 1, 39% were ASA class 2, 32% were ASA class 3, and 4% were ASA class 4. Unexpected cardiopulmonary pathology was disclosed in 27% [95% confidence interval (CI) 19-36] of the patients and led to a change in anesthesia technique or supportive actions in 43% (95% CI 25-63) of these. Unexpected pathology leading to changes in anesthesia technique or supportive actions was only disclosed in a group of patients above the age of 60 years and/or in ASA class ≥ 3.

CONCLUSION

Focused cardiopulmonary ultrasonography disclosed unexpected pathology in patients undergoing urgent surgical procedures and induced changes in the anesthesia technique or supportive actions. Pre-operative focused ultrasonography seems feasible in patients above 60 year and/or with physical limitations but not in young, healthy individuals.

Ventricular diastolic abnormalities in the critically ill

PURPOSE OF REVIEW

Left-ventricular diastolic dysfunction is associated with various conditions frequently encountered in ICU patients. Due to prolonged relaxation and increased left-ventricular stiffness, patients with diastolic dysfunction are at high risk of developing abrupt pulmonary venous congestion. The present review describes the clinical spectrum of left-ventricular diastolic abnormalities in ICU patients.

RECENT FINDINGS

Left-ventricular diastolic dysfunction is associated with a preserved ejection fraction in half of the patients presenting with acute pulmonary edema. These patients may have dramatic presentation, such as flash pulmonary edema during a hypertensive crisis. Left-ventricular diastolic dysfunction is frequently involved in patients who fail extubation and may trigger weaning pulmonary edema. Sepsis and myocardial ischemia may also be associated with left-ventricular diastolic dysfunction. The diagnosis of left-ventricular diastolic dysfunction practically relies on two-dimensional and Doppler echocardiography. Further large-scale clinical studies are needed to better characterize the prevalence, the clinical relevance and time-course of left-ventricular diastolic dysfunction in ICU patients.

SUMMARY

Left-ventricular diastolic dysfunction accounts for a growing proportion of cardiogenic pulmonary edema and weaning failure in ICU patients. It may be reversible when induced by sepsis or myocardial ischemia. Its prognostic value in the ICU settings remains to be further investigated.

Echocardiography in pediatric pulmonary hypertension

Pediatric pulmonary hypertension is a complicated disease with multiple etiologies and high mortality. Echocardiography is at the forefront of evaluation as a noninvasive, portable imaging modality that can yield diagnostic and prognostic information regarding this disease. Echocardiography is known for its ability to give an anatomic assessment of the heart and proximal blood vessels. With the additional use of Doppler echocardiography and myocardial motion assessment, the effects of elevated pulmonary pressures on the heart can be evaluated. This can allow for estimation of pulmonary artery pressures and resistances and assessment of ventricular systolic and diastolic functions. However despite its advantages, echocardiography is still an indirect assessment of pulmonary hypertension and not a substitute for cardiac catheterization. The purpose of this review is to discuss common techniques for the assessment of pulmonary hypertension by echocardiography as well as their limitations.

Perioperative assessment of diastolic dysfunction

Assessment of diastolic function should be a component of a comprehensive perioperative transesophageal echocardiographic examination. Abnormal diastolic function exists in >50% of patients presenting for cardiac and high-risk noncardiac surgery, and has been shown to be an independent predictor of adverse postoperative outcome. Normalcy of systolic function in 50% of patients with congestive heart failure implicates diastolic dysfunction as the probable etiology. Comprehensive evaluation of diastolic function requires the use of various, load-dependent Doppler techniques This is further complicated by the additional effects of dehydration and anesthetic drugs on myocardial relaxation and compliance as assessed by these Doppler measures. The availability of more sophisticated Doppler techniques, e.g., Doppler tissue imaging and flow propagation velocity, makes it possible to interrogate left ventricular diastolic function with greater precision, analyze specific stages of diastole, and to differentiate abnormalities of relaxation from compliance. Additionally, various Doppler-derived ratios can be used to estimate left ventricular filling pressures. The varying hemodynamic environment of the operating room mandates modification of the diagnostic algorithms used for ambulatory cardiac patients when left ventricular diastolic function is evaluated with transesophageal echocardiography in anesthetized surgical patients.

Sepsis and the heart

Septic shock, the most severe complication of sepsis, accounts for approximately 10% of all admissions to intensive care. Our understanding of its complex pathophysiology remains incomplete but clearly involves stimulation of the immune system with subsequent inflammation and microvascular dysfunction. Cardiovascular dysfunction is pronounced and characterized by elements of hypovolaemic, cytotoxic, and distributive shock. In addition, significant myocardial depression is commonly observed. This septic cardiomyopathy is characterized by biventricular impairment of intrinsic myocardial contractility, with a subsequent reduction in left ventricular (LV) ejection fraction and LV stroke work index. This review details the myocardial dysfunction observed in adult septic shock, and discusses the underlying pathophysiology. The utility of using the regulatory protein troponin for the detection of myocardial dysfunction is also considered. Finally, options for the management of sepsis-induced LV hypokinesia are discussed, including the use of levosimendan.

Cardiac troponin and skeletal muscle oxygenation in severe post-partum haemorrhage

INTRODUCTION

Cardiac troponin has been shown to be elevated in one-half of the parturients admitted for post-partum haemorrhage. The purpose of the study was to assess whether increased cardiac troponin was associated with a simultaneous alteration in haemoglobin tissue oxygen saturation in peripheral muscles in post-partum haemorrhage.

METHODS

Tissue haemoglobin oxygen saturation of thenar eminence muscle (StO2) was measured via near-infrared spectroscopy technology. Two sets of StO2 parameters (both isolated baseline and during forearm ischaemia-reperfusion tests) were collected at two time points: upon intensive care unit admission and prior to intensive care unit discharge. Comparisons were performed using Wilcoxon paired tests, and univariate associations were assessed using logistic regression model and Wald tests.

RESULTS

The 42 studied parturients, admitted for post-partum haemorrhage, had clinical and biological signs of severe blood loss. Initial cardiac troponin I was increased in 24/42 parturients (0.43 +/- 0.60 microrg/l). All measured parameters of muscular haemoglobin oxygen saturation, including Srecovery, were also altered at admission and improved together with improved haemodynamics, when bleeding was controlled. Multivariate analysis showed that muscular Srecovery <3%/second at admission was strongly associated with increased cardiac troponin.

CONCLUSIONS

Our study confirmed the high incidence of increased cardiac troponin, and demonstrated the simultaneous impairment in the reserve of oxygen delivery to peripheral muscles in parturients admitted for severe post-partum haemorrhage.

[Left ventricular diastolic dysfunction. Implications for anesthesia and critical care]

Over the last two decades there has been a growing recognition that cardiac function is not solely determined by systolic but also essentially by diastolic function. Left ventricular diastolic dysfunction is characterized by an impairment of ventricular filling caused either by abnormal relaxation, an active energy consuming process or decreased compliance, which is determined by passive tissue properties of the ventricle. Doppler echocardiography, including tissue Doppler imaging, has emerged as the preferred clinical tool for the assessment of left ventricular diastolic function. Recently the importance of left ventricular diastolic function is increasingly being recognized also during the perioperative period. Newer studies have shown that after cardiopulmonary bypass there is a significant decrease in left ventricular compliance. Experimental studies have demonstrated that sepsis is associated with a decrease in both active relaxation and ventricular compliance. Initial studies are also focusing on therapeutic options for patients with isolated diastolic dysfunction.