Perioperative Decision-Making in Pulmonary Hypertension.

Pulmonary hypertension (PH) is a haemodynamic manifestation of cardiorespiratory and non-cardiorespiratory pathologies. Cardiorespiratory pathologies account for nearly three-fourths of patients with PH. It is now increasingly being recognised due to routine requests for transthoracic echocardiographic examination in the perioperative setting in patients undergoing intermediate- to high-risk non-cardiac surgery. The increased risks of perioperative morbidity and mortality attributed to PH have been widely acknowledged in the literature. The importance of PH in perioperative decision-making and postoperative outcomes has had little mention in all the guidelines. Understanding the complexity of the pathophysiology of PH may help in anaesthetic and surgical decision-making. Preoperative evaluation and risk assessment are guided by the nature, extent, invasiveness, and duration of surgery. Surgical decision-making and anaesthetic management involve preoperative risk stratification, understanding the interactions between surgical procedures and PH, and understanding the interactions between anaesthetic procedures, PH, and cardiopulmonary interactions. Intraoperative and postoperative monitoring is crucial for maintaining the haemodynamic parameters and helps titrate anaesthetic agents and medication. This narrative review focusses on all issues related to anaesthetic and surgical challenges in patients with PH. This review aimed to suggest a preoperative evaluation plan, surgical decision-making, anaesthetic plan, and anaesthetic management based on the evidence available in the literature.

A review of the therapeutic management of multiple ventricular septal defects.

BACKGROUND AND AIM: We showed in our anatomical review, ventricular septal defects existing as multiple entities can be considered in terms of three major subsets. We address here the diagnostic challenges, associated anomalies, the role and techniques of surgical instead of interventional closure, and the outcomes, including reinterventions, for each subset. METHODS: We reviewed 80 published investigations, noting radiographic findings, and the results of clinical imaging elucidating the location, number, size of septal defects, associated anomalies, and the effect of severe pulmonary hypertension. RESULTS: Overall, perioperative mortality for treatment of residual multiple defects has been cited to be between 0% and 14.2%, with morbidity estimated between 6% and 13%. Perioperative mortality is twice as high for perimembranous compared to muscular defects, with the need for reoperation being over four times higher. Perventricular hybrid approaches are useful for the closure of high anterior or apical defects. Overall, the results have been unsatisfactory. Pooled data reveals incidences between 2.8% and 45% for device-related adverse events. Currently, however, outcomes cannot be assessed on the basis of the different anatomical subsets. CONCLUSIONS: We have addressed the approaches, and the results, of therapeutic treatment in terms of coexisting discrete defects, the Swiss-cheese septum, and the arrangement in which a solitary apical muscular defect gives the impression of multiple defects when viewed from the right ventricular aspect. Treatment should vary according to the specific combination of defects.

Transesophageal Echocardiographic Estimation of Coronary Sinus Blood Flow for Predicting Favorable Postoperative Transit Time Coronary Graft Flow Measurements: A Pilot Study.

BACKGROUND: Augmentation of coronary artery flow by surgical grafting increases coronary sinus blood flow (CSBF), which can be quantified on transesophageal echocardiography (TEE). However, transit time flowmetry (TTF) technology remains the most used intraoperative technique for coronary artery graft assessment. The purpose of the present pilot study was to evaluate the predictive value of TEE-based CSBF estimation for identifying favorable TTF graft measurements. DESIGN: Prospective observational study. SETTING: Single university hospital. PATIENTS: Forty patients undergoing triple vessel coronary artery bypass grafting. MEASUREMENTS AND MAIN RESULTS: CSBF was assessed on TEE examination before and after revascularization, estimating the percentage increase in CSBF (∆CSBF). Postoperative TTF graft measurements were averaged to compute mean diastolic filling (DF) and pulsatility index (PI). Subjects were grouped based on favorable (PI ≤ 3, DF ≥ 50%) and unfavorable (PI > 3, DF < 50%) parameters. The group with PI ≤ 3 (n = 32) had significantly higher ∆CSBF compared with the group with PI > 3 (n = 8) (38.22% ± 12.05%, 13.75% ± 3.37%, p < 0.001). ∆CSBF was higher in the DF ≥ 50% group (n = 35) (36.40 ± 12.99) in contrast to DF < 50% group (n = 5) (11.80 ± 2.59%). A strong negative and significantly positive correlation was observed between ∆CSBF with PI, DF (r = -0.903, 0.571, respectively, p < 0.001). A ∆CSBF ≥15.5% was found to predict a mean PI ≤ 3 and DF ≥ 50% with sensitivity and specificity of 100% and 62.5% for PI and 100% and 100% for DF. A ∆CSBF ≥19% demonstrated a sensitivity and specificity of 100% and 100%, 100% and 91.4% for prediction of PI ≤ 3 and DF ≥ 50%, respectively. CONCLUSION: TEE-based demonstration of an augmented CSBF can ensure favorable TTF graft parameters, guiding the adequacy of surgical revascularization.

A Comparison of the Strain and Tissue Doppler-Based Indices as Echocardiographic Correlates of the Left Ventricular Filling Pressures.

OBJECTIVES: Diastolic strain and strain rate, combined with E (peak transmitral velocity), have been proposed as novel noninvasive predictors of left ventricle (LV) filling pressures, avoiding angulation errors inherent to tissue Doppler indices (TDI). The primary objective was to study the correlation of strain-based indices (SBI) and TDI with pulmonary artery catheter-derived LV end-diastolic pressures (LVEDP). The secondary aim was to determine appropriate cut-off of indices to predict LVEDP ≥15 mmHg. DESIGN: A prospective observational clinical study. SETTING: Single university hospital. PARTICIPANTS: One hundred twenty adults with preserved ejection fraction (EF) undergoing coronary artery bypass grafting. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Two-dimensional speckle-tracking echocardiography estimated global longitudinal diastolic strain (Ds) and strain rate (DSr) at peak mitral filling to compute E/Ds and E/10DSr. TDI was measured as the ratio of E and e' (mitral annular diastolic velocity). E/e', E/Ds, and E/10DSr were significantly higher (p < 0.001) in patients with LVEDP ≥15 mm Hg (31/120). Correlation of E/Ds, E/10DSr with LVEDP was R = 0.86 and 0.88 (p < 0.001), respectively, compared with a correlation of R = 0.63 (p < 0.001) for E/e'. SBI correlated well with LVEDP ≥15 mm Hg compared with TDI. E/Ds ≥11 and E/10DSr ≥12 had higher sensitivity and specificity (96.77%, 93.26%; 100%, 96.63%, respectively; area under the curve [AUC] = 0.99) than E/e'≥13 (74%,75%; AUC = 0.84) for prediction of LVEDP ≥15 mmHg. SBI accurately predicted elevated LVEDP in the indeterminate zone of 8

Transcutaneous nerve stimulation for pain relief during chest tube removal following cardiac surgery.

BACKGROUND AND AIMS: In patients undergoing open heart surgery, chest tubes are removed postoperatively when patients are well awake and stable. Pain during chest tube removal can be moderate to severe and can be the worst experience of hospitalization. Various modalities of pain relief during chest tube removal have been tried with variable results. We sought to examine the effect of transcutaneous electrical nerve stimulation (TENS) as an intervention for pain relief during chest tube removal after cardiac surgery. MATERIAL AND METHODS: In a tertiary care center, fifty patients undergoing open heart surgery were randomized into two groups. Group TENS (n = 25) received TENS from 30 min before and continued up to 30 min after chest tube removal. Control Group (n = 25) did not receive TENS. In both the groups, additional analgesic medication was provided on demand, besides the standard analgesic regime which was injection ketorolac 30 mg intramuscularly every 8 h. Patients were studied for pain during chest drain removal and pain related nausea, vomiting, and sense of well-being. RESULTS: Mean visual analog pain score assessed for chest tube removal was significantly less 4.1 ± 1.2 (P < 0.05) in TENS Group as compared to 6.1 ± 0.8 in Control Group. Significantly greater number of patients (n = 14) (P < 0.05) in Control Group demanded additional analgesia as compared to TENS Group (n = 5). Feeling of well-being, improvement in appetite, and sleep was better in TENS Group as compared to Control Group. CONCLUSION: We conclude that TENS might not replace the conventional analgesics but has definite adjuvant role in decreasing pain scores and improves sense of well-being during chest tube removal after cardiac surgery.

Echocardiographic Predictors of Immediate Postoperative Outcomes in Patients With Severe Left Ventricular Systolic Dysfunction Undergoing On-Pump Coronary Artery Bypass Grafting.

OBJECTIVES: The postoperative course following on-pump coronary artery bypass grafting (CABG) in patients with severe left ventricular (LV) systolic dysfunction is often unpredictable. Therefore, the aim of this study was to identify predictors of poor postoperative outcome in this subset of patients. DESIGN: Prospective observational study SETTING: Single university hospital PARTICIPANTS: Forty patients with severe LV systolic dysfunction undergoing isolated on-pump CABG INTERVENTIONS: None MEASUREMENTS AND MAIN RESULTS: Comprehensive transesophageal echocardiographic examination was performed to obtain the indices of systolic and diastolic LV function after induction of anesthesia. A poor postoperative outcome was defined as patient death or vasoactive inotropic score≥20 for at least 6 hours and/or requiring intra-aortic balloon counterpulsation and/or mechanical ventilation for≥24 hours. Poor postoperative outcome was observed in 40% (16/40) of patients. Patients with poor postoperative outcomes had a significantly higher systolic dyssynchrony index, septal-lateral delay with a significantly lower global longitudinal strain and isovolumic acceleration, end-diastolic volume, end-systolic volume, and lateral and medial mitral annulus systolic velocity. In a binary logistic regression model, global longitudinal strain (odds ratio, 1.5, confidence interval [CI] 95%, 1.19-1.88, p = 0.001), septal-lateral delay (odds ratio, 1.02, 95% CI, 1.01-1.03; p = 0.001) and systolic dyssychrony index (odds ratio, 1.3, 95% CI, 1.13-1.48; p = 0.000) were found to be predictors of poor postoperative outcome. CONCLUSION: Global longitudinal strain, systolic dyssynchrony index, and septal-lateral delay were reliable and accurate predictors of adverse outcomes in patients with severe LV systolic dysfunction undergoing on-pump CABG.

Effect of Levosimendan on Diastolic Function in Patients Undergoing Coronary Artery Bypass Grafting: A Comparative Study.

PURPOSE: To compare the efficacy of levosimendan with nitroglycerin in patients with isolated diastolic dysfunction undergoing coronary artery bypass grafting. PROCEDURE: Thirty patients with isolated diastolic dysfunction undergoing on-pump coronary artery bypass grafting were randomized into 2 groups receiving levosimendan or nitroglycerin infusion. The infusion was started before sternotomy and continued in the postoperative period. Perioperatively, diastolic function was serially evaluated at 3 different time points using echocardiography. N-terminal fragment of pro-B-natriuretic peptide (NT-proBNP) levels were measured in both the groups. RESULTS: There was a significant improvement in diastolic function as measured by isovolumic relaxation time (P = 0.0001, P = 0.001) and deceleration time (P = 0.0001, P = 0.0001) in the levosimendan group from the baseline in patients with impaired relaxation. Similarly, tissue Doppler imaging also revealed an improvement from the baseline in patients with a pseudonormal pattern (P = 0.018, P = 0.001). Furthermore, there was a significant improvement in the above parameters when compared with the nitroglycerin group. The NT-proBNP levels also demonstrated a similar pattern between the 2 groups (P = 0.03, P = 0.02) when levosimendan was compared with nitroglycerin in patients with a pseudonormal pattern on echocardiography. CONCLUSIONS: Levosimendan is superior to nitroglycerin in improving diastolic function irrespective of coronary revascularization.

Perioperative endothelin levels in patients undergoing intracardiac repair for tetralogy of Fallot.

BACKGROUND: Endothelin, a pro-inflammatory molecule, had been extensively studied in patients with cardiovascular illness. Impact on the perioperative outcome of patients with cyanotic congenital heart defects is still unknown. In the present study, we report perioperative changes in endothelin levels and their correlation with preoperative factors and clinical outcomes in a group of patients with tetralogy of Fallot (TOF) undergoing definitive repair. METHODOLOGY: 167 patients with TOF undergoing intracardiac repair under cardiopulmonary bypass were studied. Endothelin levels were taken at three different points of time and correlated with different clinical variables. RESULTS: The baseline endothelin level correlated with patients' nutritional status and degree of cyanosis. The magnitude of inflammatory response in the post-cardiopulmonary bypass (post-CPB) period as measured by endothelin level was much higher and correlated more consistently with adverse clinical outcomes in the younger age group. On multivariable analysis, age at operation, preoperative degree of hypoxemia, and endothelin levels were found to be independent predictors of clinical outcomes. CONCLUSIONS: A rise in serum endothelin levels in patients with TOF undergoing definitive repair on CPB, with preoperative severity of cyanosis, nutritional status, and adverse clinical outcomes. The endothelin levels may be monitored to identify patients with cyanosis at an increased risk of exhibiting augmented inflammatory response to CPB.

Comparison of Left Ventricular Global Longitudinal Strain with Ejection Fraction as a Predictor for Peri-operative IABP Insertion in Patients Undergoing Off-Pump Coronary Artery Bypass Grafting: A Pilot Study.

Background: Prophylactic use of intra-aortic balloon pump (IABP) mainly depends on left ventricular (LV) systolic function. Global longitudinal strain (GLS) is a robust prognostic parameter for LV strain. It has proved to be more sensitive than LV ejection fraction (EF) as a measure of LV systolic function and is a strong predictor of outcome. Aim: To determine whether GLS can be used as a reliable marker and its cut-off value for IABP insertion in patients undergoing elective off-pump coronary artery bypass grafting (OPCABG). Settings and Design: A prospective observational clinical study which included 100 adult patients scheduled for elective OPCABG. Materials and Methods: Two-dimensional (2D) speckle tracking echocardiography (STE)-estimated GLS was computed and compared with LV EF measured by three dimensional (3D) echocardiography for the insertion of IABP. The intensive care unit (ICU) parameters were correlated with echocardiographic parameters to predict early post-operative outcome. Results: IABP insertion correlates better with GLS (post-revascularization > pre-revascularization) than with 3D LV EF. Receiver operating characteristic (ROC) curve analysis revealed the highest area under the curve (AUC, 0.972) with a cut-off value of > -9.8% for GLS compared to 3D LV EF (AUC, 0.938) with a cut-off value of ≤ 44%. ICU parameters show better correlation with E/e'> GLS > WMSI than 3D LV EF. Conclusion: GLS is a better predictor of IABP insertion compared to 3D LV EF in patients undergoing OPCABG.

The surgical anatomy of hearts with isomeric atrial appendages-implications for surgical management.

OBJECTIVES: The most severe combinations of cardiac malformations exist in individuals having jumbled-up thoracic and abdominal organs. These patients make up 2 distinct syndromes. As yet, the consensus is lacking on how best to describe the subsets. The subsets are frequently grouped together in terms of 'heterotaxy'. The surgical approaches to the subsets, however, are markedly different. We reviewed our experiences with regard to the anatomy as observed in the autopsy room, by the analysis of computed tomographic studies, and in the operating room, to assess whether the lesions might be segregated on the basis of isomerism of the atrial appendages. METHODS AND RESULTS: A review of our findings from the examination of specimens from several archives, along with investigation of a large cohort of patients being prepared for surgical treatment, showed that individuals can uniformly be segregated into subgroups on the basis of isomeric arrangement of the atrial appendages. In all instances, this was made possible by using the criterion of the extent of the pectinate muscles within the appendages as judged relative to the atrial vestibules. Segregation on this basis, which correlated excellently with the bronchial arrangement, sets the scene for an appropriate description of the remainder of the heart, providing the cardiac surgeon with all the inferences required for appropriate surgical intervention. CONCLUSIONS: When assessing individuals having the features of so-called 'heterotaxy', it is possible to segregate the groups into subsets of individuals having either isomeric right or left atrial appendages. This approach provides the framework for the assessment of appropriate surgical management.

A Century With Craniopagus Twin Separation Surgeries: Nihilism to Optimism.

Craniopagus conjoined twins are extremely rare, reported 1 in 2.5 million live births. To date, 62 separation attempts in 69 well-documented cases of craniopagus twins have been made. Of these, 34 were performed in a single-stage approach, and 28 were attempted in a multistage approach. One or both twins died of massive intraoperative blood loss and cardiac arrest in 14 cases. We report our surgical experience with conjoined craniopagus twins (JB) with type III total vertical joining and shared circumferential/circular sinus with left-sided dominance. A brief review of the literature is also provided. In our twins, the meticulous preoperative study and planning by the multidisciplinary team consisting of 125-member, first-staged surgical separation consisted of creation of venous conduit to bypass part of shared circumferential sinus and partial hemispheric disconnection. Six weeks later, twin J manifested acute cardiac overload because of one-way fistula development from blocked venous bypass graft necessitating emergency final separation surgery. Unique perioperative issues were abnormal anatomy, hemodynamic sequelae from one-way fistula development after venous bypass graft thrombosis, cardiac arrest after massive venous air embolism requiring prolonged cardiopulmonary resuscitation, and return of spontaneous circulation at 15 minutes immediately after separation. This is the first Indian craniopagus separation surgery in a complex total vertical craniopagus twin reported by a single-center multidisciplinary team. Both twins could be sent home, but one remained severely handicapped. Adequate perioperative planning and multidisciplinary team approach are vital in craniopagus twin separation surgeries.

Perioperative Management of a Child with Klippel-Feil Syndrome and Severe Uncorrected Aortic Stenosis Undergoing Cervical Spine Stabilization.

Severe stenotic aortic valve poses serious anesthetic challenges because of the fixed cardiac output and complex hemodynamics. The challenges magnify in the presence of a difficult airway which not only puts the airway at risk but also disturbs the hemodynamics, which can negatively impact the patient outcome. Moreover, prone positioning, intraoperative hemodynamics, recovery, and extubation are equally challenging for management. This case report highlights the perioperative management of a child with severe uncorrected aortic stenosis and Klippel-Feil syndrome posted for cervical spinal stabilization under anesthesia.

Comparison of flow-independent parameters for grading severity of aortic stenosis using intraoperative transesophageal echocardiography - A prospective observational study.

Introduction: Discrepancies have been reported in grading of severity of aortic stenosis. We propose to compare Aortic valve area by continuity equation, Dimensionless Index and Acceleration time/Ejection time in patients with documented severe aortic stenosis with normal left ventricular function by TEE after induction of anesthesia. This might give use insight about the best parameter we can rely on intra-operatively for decision making. Methodology: 60 patients with severe AS undergoing elective cardiac surgery were enrolled in our study. Post intubation trans-thoracic echocardiography (TEE) was performed and above mentioned parameters was noted. Results: 96.7 % of patients continued in severe AS category when AS was measured using AVA as echo parameter. So there is 3.3 % disparity. There was disparity in 13.3% of cases when DI was considered. And there was 43.3% disparity when AT/ET was considered. Conclusion: Perioperative grading of aortic stenosis continues to be a challenge for cardiac anesthesiologists. Multiple echocardiographic parameters have to be considered. We have found AVA and DI to have less disparity compared to AT/ET.

A Review on the Surgical Management of Subvalvular Aneurysm.

The present perspective is a synthesis of published investigations in the setting of subvalvular aortic aneurysms. We identified 75 investigations and reviewed the clinical presentation, diagnostic modalities used, surgical techniques employed, and their outcomes. Clinical presentation, radiographic findings, transthoracic and transesophageal echocardiography, electrocardiogram-gated computerized tomography, and magnetic resonance imaging provided the diagnostic information and were used to define the disease entity before surgery. In this article, we have attempted to address several issues concerning establishment of diagnosis, varied clinical presentation, and their management. We submit that an increased appreciation of this disease entity will contribute to improved surgical management.

A Review of the Surgical Management of Anomalous Connection of the Right Superior Caval Vein to the Morphologically Left Atrium and Biatrial Drainage of Right Superior Caval Vein.

The present perspective is a synthesis of published investigations in the setting of anomalous connection of the right superior caval vein to the morphologically left atrium or biatrial drainage of the right caval vein. We identified 57 suitable cases from 97 investigations, reviewing the clinical presentation, diagnostic modalities utilized, surgical techniques used, and their outcomes. Clinical presentation, radiographic findings, saline contrast echocardiography, computed tomographic angiocardiography, radionuclide perfusion scan, magnetic resonance imaging, and angiocardiography provided the diagnostic information and were used to define the disease entities before surgery. We have also addressed several issues concerning the influence of the so-called heterotaxy: the establishment of the diagnosis, the variation in clinical presentation, and subsequent management. For the overall group of patients undergoing either surgical intervention or transcatheter treatment with an Amplatzer vascular plug, the operative mortality remains high at 9.5%. We submit that an increased appreciation of these disease entities will contribute to improved future surgical management.

Ventriculo-peritoneal shunt surgery in an infant with double aortic arch, patent ductus arteriosus and atrial septal defect.

Double aortic arch with patent ductus arteriosus and atrial septal defect is an uncommon association. Such complex cardiac lesions may complicate an otherwise normal anesthetic course. We came across a case with aqueductal stenosis and hydrocephalus, scheduled for ventriculo-peritoneal shunt surgery, on an emergent basis. The child was managed successfully. The anesthetic implications of resultant left-to-right shunt with increased intracranial pressure have been described.