Thoracic epidural bupivacaine attenuates supraventricular tachyarrhythmias after pulmonary resection

Risk factors and survival analysis of arrhythmia following lung cancer surgery: a retrospective study

Background

Surgical treatment of lung cancer is one of the important treatments for early-stage non-small cell lung cancer (NSCLC). However, arrhythmia, especially atrial fibrillation (AF) and supraventricular arrhythmia, are quite common among patients after surgical treatment of lung cancer. The impact of postoperative arrhythmia (PA) on survival is rarely reported. Our aim was to evaluate the risk factors of PA and its impact on overall survival (OS) after lung cancer surgery.

Methods

A total of 344 patients diagnosed with NSCLC who underwent lung cancer surgery were enrolled in this study. These patients were divided into two groups based on the occurrence of PA. Univariate and multivariate logistic regression analyses were conducted to identify the risk factors of PA. The Kaplan-Meier method was applied to show the OS differences between the two groups.

Results

The incidence of PA was 16% (55/344). Among these 55 patients, 20 had AF, 30 had sinus tachycardia, and 5 had premature beats. A total of 332 patients underwent lung cancer radical resection. Operation type (P<0.001), preoperative abnormal ECG (P=0.032), transfusion (P=0.016), postoperative serum potassium concentration (P=0.001) and clinical stage (P<0.05) were risk factors for PA. PA (HR 2.083, 95% CI, 1.334–3.253; P=0.001), age (HR 1.543, 95% CI, 1.063–2.239; P=0.025) and mediastinal lymph node metastasis (HR 2.655, 95% CI, 1.809–3.897; P<0.001) were independent prognostic risk factors for OS by multivariate cox analysis.

Conclusions

We identified PA as an independent prognostic risk factor to predict poor OS in patients who underwent lung cancer surgery and had risk factors for PA. We therefore provides guidance for PA in improving the prognosis of lung cancer patients.

Neuromodulation for Ventricular Tachycardia and Atrial Fibrillation: A Clinical Scenario-Based Review

Autonomic dysregulation in cardiovascular disease plays a major role in the pathogenesis of arrhythmias. Cardiac neural control relies on complex feedback loops consisting of efferent and afferent limbs, which carry sympathetic and parasympathetic signals from the brain to the heart and sensory signals from the heart to the brain. Cardiac disease leads to neural remodeling and sympathovagal imbalances with arrhythmogenic effects. Preclinical studies of modulation at central and peripheral levels of the cardiac autonomic nervous system have yielded promising results, leading to early stage clinical studies of these techniques in atrial fibrillation and refractory ventricular arrhythmias, particularly in patients with inherited primary arrhythmia syndromes and structural heart disease. However, significant knowledge gaps in basic cardiac neurophysiology limit the success of these neuromodulatory therapies. This review discusses the recent advances in neuromodulation for cardiac arrhythmia management, with a clinical scenario-based approach aimed at bringing neurocardiology closer to the realm of the clinical electrophysiologist.

Segmental thoracic epidural anaesthesia in a dog undergoing intercostal thoracotomy and lung lobectomy

A seven-year-old, 25-kg female crossbreed dog received segmental thoracic epidural anaesthesia for left lateral thoracotomy and lung lobectomy. At presentation mild exercise intolerance and weight loss were reported. A chest CT scan revealed a solitary soft tissue mass in the left caudal lobe. Lung lobectomy surgery was scheduled. Under isoflurane anaesthesia, an epidural catheter was threaded through T13–L1 and advanced 50 mm cranially. Bupivacaine and morphine were administered 30 minutes before incision and at 12-hour intervals thereafter. To minimise side effects, the postoperative dose was titrated to guarantee segmental analgesia. Purposeful movements and signs of sympathetic stimulation in response to surgery were not observed. Intraoperatively, a transient 13% increase in arterial blood pressure occurred, while heart rate remained stable compared with baseline. Although the intended postoperative dose was decreased to prevent side effects, pain scores were below the analgesic intervention score. The catheter was removed on the fourth postoperative day. Complications and neurological sequelae were not noticed.

The effect of bilateral intrapleural infusion of lidocaine with fentanyl versus only lidocaine in relieving pain after coronary artery bypasses surgery

Background and Objective:

Pain control during surgery in order to cause analgesia and reduce the somatic and autonomic response may decrease the morbidity. Intrapleural catheter embedding during surgery under direct vision of surgeon is safe and easy and without potential risk of thoracic epidural block. The aim of this study was to investigate the effect of bilateral intrapleural infusion of lidocaine with fentanyl versus only lidocaine in relieving pain after coronary artery bypass surgery.

Methods:

In this prospective randomized double blind clinical trial,130 adult patients undergoing elective CABG with age range of 20 to 60 years were divided into two groups receiving either lidocaine and fentanyl (group A) or lidocaine (group B). The analgesia was evaluated every two hours in all intubated and non-intubated patients using Visual analog scale (VAS) and data were analyzed using SPSS software package.

Results:

Of all patients, 67 (51.5%) were males and 63 (48.5%) were females. The average age of subjects was 53.49 ± 5.099 years. Mean pain score six hours after the surgery was statistically different between the groups at all times.

Conclusion:

The pain in patients receiving combination of lidocaine and fentanyl is less than patients receiving only lidocaine.

Clinical neurocardiology defining the value of neuroscience-based cardiovascular therapeutics

The autonomic nervous system regulates all aspects of normal cardiac function, and is recognized to play a critical role in the pathophysiology of many cardiovascular diseases. As such, the value of neuroscience-based cardiovascular therapeutics is increasingly evident. This White Paper reviews the current state of understanding of human cardiac neuroanatomy, neurophysiology, pathophysiology in specific disease conditions, autonomic testing, risk stratification, and neuromodulatory strategies to mitigate the progression of cardiovascular diseases.

Association of thoracic epidural analgesia with risk of atrial arrhythmias after pulmonary resection: a retrospective cohort study

PURPOSE

Atrial arrhythmias are common after non-cardiac thoracic surgery. We tested the hypothesis that TEA reduces the risk of new-onset atrial arrhythmias after pulmonary resection.

METHODS

We evaluated patients who had pulmonary resection. New-onset atrial arrhythmias detected before hospital discharge was our primary outcome. Secondary outcomes included other cardiovascular complications, pulmonary complications, time-weighted average pain score over 72 h, and duration of hospitalization. Patients with combination of general anesthesia and TEA were matched on propensity scores with patients given general anesthesia only. The matched groups were compared by use of logistic regression, linear regression, or Cox proportional hazards regression, as appropriate.

RESULTS

Among 1,236 patients who had pulmonary resections, 937 received a combination of general anesthesia and TEA (TEA) and 299 received general anesthesia only (non-TEA). We successfully matched 311 TEA patients with 132 non-TEA patients. We did not find a significant association between TEA and postoperative atrial arrhythmia (odds ratio (95 % CI) of 1.05 (0.50, 2.19), P = 0.9). TEA was not significantly associated with length of hospital stay or postoperative pulmonary complications (odds ratio (95 % CI) of 0.71 (0.22, 2.29), P = 0.47). TEA patients experienced fewer postoperative cardiovascular complications; although the association was not statistically significant (odds ratio (95 % CI) of 0.30 (0.06, 1.45), P = 0.06). Time-weighted average pain scores were similar in the two groups.

CONCLUSION

TEA was not associated with reduced occurrence of postoperative atrial arrhythmia. Although postoperative pulmonary complications were similar with and without TEA, TEA patients tended to experience fewer cardiovascular complications.

Supraventricular arrhythmias after thoracotomy: is there a role for autonomic imbalance?

Supraventricular arrhythmias are common rhythm disturbances following pulmonary surgery. The overall incidence varies between 3.2% and 30% in the literature, while atrial fibrillation is the most common form. These arrhythmias usually have an uneventful clinical course and revert to normal sinus rhythm, usually before patent's discharge from hospital. Their importance lies in the immediate hemodynamic consequences, the potential for systemic embolization and the consequent long-term need for prophylactic drug administration, and the increased cost of hospitalization. Their incidence is probably related to the magnitude of the performed operative procedure, occurring more frequently after pneumonectomy than after lobectomy. Investigators believe that surgical factors (irritation of the atria per se or on the ground of chronic inflammation of aged atria), direct injury to the anatomic structure of the autonomic nervous system in the thoracic cavity, and postthoracotomy pain may contribute independently or in association with each other to the development of these arrhythmias. This review discusses currently available information about the potential mechanisms and risk factors for these rhythm disturbances. The discussion is in particular focused on the role of postoperative pain and its relation to the autonomic imbalance, in an attempt to avoid or minimize discomfort with proper analgesia utilization.

Postoperative atrial fibrillation

Postoperative atrial fibrillation (POAF) is common among surgical patients and associated with a worse outcome. Pathophysiology of POAF is not fully disclosed, and several perioperative factors could be involved. Direct cardiac stimulation from perioperative use of catecholamines or increased sympathetic outflow from volume loss/anaemia/pain may play a role. Metabolic alterations, such as hypo-/hyperglycaemia and electrolyte disturbances, may also contribute to POAF. Moreover, inflammation, both systemic and local, may play a role in its pathogenesis. Strategies to prevent POAF aim at reducing its incidence and ameliorate global outcome of surgical patients. Nonpharmacological prophylaxis includes an adequate control of postoperative pain, the use of thoracic epidural analgesia, optimization of perioperative oxygen delivery, and, possibly, modulation of surgery-associated inflammatory response with immunonutrition and antioxidants. Perioperative potassium and magnesium depletion should be corrected. The impact of those interventions on patients outcome needs to be further investigated.

Effects of high thoracic epidural anesthesia on atrial electrophysiological characteristics and sympathetic nerve sprouting in a canine model of atrial fibrillation

High thoracic epidural anesthesia (HTEA) blocks the afferent and efferent cardiac sympathetic nerve fibers and may affect atrial electrophysiological characteristics and nerve sprouting in patients with atrial fibrillation (AF). In this study, 18 dogs were randomly divided into a control group (n = 6), in which dogs were atrially paced at 400 beats/min for 6 weeks; an HTEA group (n = 6), in which dogs underwent atrial pacing and HTEA for 6 weeks; and a sham-operated group (n = 6), in which dogs underwent the operation but did not receive atrial pacing or HTEA. Electrophysiological examinations were performed in all groups. Cardiac nerves were immunocytochemically stained with anti-growth-associated protein 43 (GAP43) and anti-tyrosine hydroxylase (TH) antibodies. The protein expressions of nerve growth factor (NGF), GAP43 and TH in atrial myocardium were also studied by western blot. In addition, the plasma levels of C-reactive protein (CRP) and norepinephrine, as well as atrial production of superoxide anion (O(2)(·-)) and malondialdehyde, were measured. In the HTEA group, atrial effective refractory period increased (P < 0.05) and AF maintenance decreased (P < 0.01) significantly compared with the control group. The densities of GAP43-positive nerves and TH-positive nerves were significantly lower in the HTEA group compared with the control group. The protein levels of NGF, GAP43 and TH were also lower in the HTEA group compared with the control group. A significant positive correlation between the expressions of NGF and GAP43 (P < 0.01) was observed. A similar correlation was demonstrated for NGF and TH (P < 0.01) in our study. Furthermore, the plasma levels of CRP and norepinephrine, as well as the amount of O(2)(·-) and malondialdehyde produced from myocardium, decreased in the HTEA group compared with the control group. In conclusion, HTEA inhibited electrical and nerve remodeling and reduced the maintenance of AF in a canine AF model, in which process HTEA exhibited anti-inflammatory and antioxidant effects, indicating that, in addition to the efferent cardiac sympathetic nerve, afferent fibers also play an important role in the initiation and/or maintenance of AF.

[Concepts for perioperative pain therapy. A critical stocktaking]

Despite numerous publications, new guidelines for the treatment of acute pain and efforts from a number of initiatives, there is still a tremendous need for improvement in postoperative pain therapy. One of the reasons for the shortcomings in the care of patients with postoperative pain is the lack of applicability of guidelines in daily clinical practice. Therefore, simple but effective and easy to implement concepts need to be developed. In the following review, different concepts that have been developed over recent years are presented and evaluated for their effectiveness. One of these is the notion of balanced analgesia, currently probably one of the most widely used perioperative therapy concepts. The idea of this concept is to reduce the doses of analgesics, e.g. opioids, through combinations of different classes of analgesics, thereby reducing their side effects. However, recent studies and essential meta-analyses indicate pitfalls using this concept. The pros and cons will be discussed and ideas on how to deal with balanced analgesia in daily practice will be given. Another pain concept of "procedure-specific postoperative pain therapy", is an appealing idea of an international initiative from surgeons and anaesthesiologists and an essential part of the German S3 guidelines for acute pain released last year. Critical evaluation of the available recommendations for procedure-specific analgesia together with the presentation of relatively simple but evidence-based algorithms for specific procedures may help to implement this concept in clinical routine.

Risk factors for an intraoperative arrhythmia during esophagectomy

PURPOSE

Arrhythmias after an esophagectomy (most commonly atrial fibrillation) are a significant contributing factor to patient morbidity. However, the significance of an intraoperative arrhythmia is not completely understood. The aim of this retrospective study was to determine the occurrence and risk factors for developing intraoperative arrhythmias in patients undergoing an esophagectomy.

MATERIALS AND METHODS

We reviewed the records of 427 patients who underwent a transthoracic esophagectomy between 2001 and 2005. Variables such as age, sex, hypertension, diabetes, cardiac disease, preoperative pulmonary function test (PFT) results, cancer level, combined radiochemotherapy, intrathoracic cavity adhesions and anastomosis site, hemoglobin, central venous pressure (CVP), fluid balance, serum potassium level, dose of vasopressors, temperature, and combined general and epidural anesthesia were analyzed as risk factors for the occurrence of an arrhythmia. We defined this arrhythmia as one not originating from the sinus node.

RESULTS

The incidence of intraoperative arrhythmia in this subset of patients was 17.1%, with a 37.2% reoccurrence rate during the first three postoperative days. Univariate and multivariate analysis revealed the presence of heart disease, poor PFTs, cervical anastomosis, elevated CVP, and higher ephedrine doses to be independent predictors of the development of an intraoperative arrhythmia.

CONCLUSION

The incidence of intraoperative arrhythmia during esophagectomy was 17.1% with a 37.2% of reoccurrence rate.

Anaesthesia and postoperative analgesia in older patients with chronic obstructive pulmonary disease: special considerations

Chronic obstructive pulmonary disease (COPD) and older age are known to be independent risk factors for severe perioperative adverse outcomes after surgery. A basic understanding of the disease, careful preoperative evaluation and preparation of the patient, as well as a tailored anaesthetic management plan might help to decrease complications in this patient population. Aging affects the pharmacokinetics and pharmacodynamics of almost all drugs and therefore the dosage must be adapted in older patients. The type of anaesthesia (general versus regional anaesthesia) has no substantial effect on perioperative morbidity and mortality. Most patients, even with severe COPD, tolerate general anaesthesia without major problems. One important goal of the anaesthetic management is to prevent reflex-induced bronchoconstriction, which can be accomplished by the use of volatile anaesthetics. Early recovery can be facilitated by the use of short-acting drugs, such as propofol and the new opioid remifentanil. Judicious use of neuromuscular blocking agents is necessary because of the risk of residual paralysis, and those agents associated with histamine liberation should be avoided. Ventilation requires long expiration times to avoid air trapping, and hyperinflation to avoid the possible threat of pneumothorax and a decrease in cardiac output. For postoperative analgesia, a balanced regimen consisting of regional analgesia with local anaesthetics and NSAIDs should be preferred. This will enhance analgesia and reduce opioid toxicity, which is important in patients with COPD, where respiratory depression is especially dangerous.