Pilot-RCT of an integrative group therapy for patients with refractory irritable bowel syndrome (ISRCTN02977330).

OBJECTIVE: Different forms of psychotherapeutic treatments have been proven effective in irritable bowel syndrome (IBS), but disorder-oriented and integrative concepts are still rare. Therefore, we implemented and evaluated an integrative group therapeutic concept within an interdisciplinary tertiary care clinic for functional gastrointestinal disorders (FGIDs). AIMS: present our integrative group concept, assess feasibility issues, and evaluate efficacy. METHODS: A pilot-RCT with a randomized controlled wait-listed group design was conducted. The treatment concept was a disorder-oriented multicomponent group therapy (12 90-min weekly sessions) integrating interactive psychoeducation, gut-directed hypnotherapy, and open group phases. All patients received enhanced medical care and completed a short online diary as an active wait-listed control condition. INCLUSION CRITERIA: refractory IBS diagnosed as somatoform autonomic dysfunction of the lower gastrointestinal tract (SAD). PRIMARY OUTCOME: IBS symptom severity (IBS-SSS). RESULTS: Of 294 patients, 220 had IBS (ROME III), 144 were diagnosed as SAD (ICD-10), 51 were eligible regarding inclusion/exclusion criteria, and 30 consented to participate (group intervention: n=16, wait-listed control condition: n=14). Only 1 patient dropped out. Intention-to-treat-analysis with repeated-measures mixed ANOVA showed that the group intervention was not significantly superior to the wait-listed control condition. Nevertheless, the calculated effect size for the between-group difference in IBS-SSS at the end of treatment (post) was moderate (d=0.539). CONCLUSION: Our disorder-oriented integrative group intervention for IBS proved to be acceptable and feasible in an interdisciplinary tertiary care setting. There is promise in this intervention, but a larger RCT may be needed to investigate efficacy.

Incidence of clinically symptomatic pneumothorax in ultrasound-guided infraclavicular and supraclavicular brachial plexus block.

The use of periclavicular brachial plexus block as regional anaesthesia for surgical procedures on the upper extremity is common. However, the proximity of the pleura results in a risk of pneumothorax. Without ultrasound monitoring, the pneumothorax risk has been reported to be as high as 6.1%. We conducted a prospective, observational study to examine the risk of pneumothorax in 6366 ultrasound-guided periclavicular plexus blocks. All patients with a clinically manifest and radiologically confirmed pneumothorax were analysed. Clinically symptomatic pneumothorax occurred in four patients (0.06%; 95% CI 0.001-0.124), in three of them after a two-day latency period. Ultrasound guidance does therefore appear to reduce the risk of pneumothorax. Although all of the anaesthesiologists involved in the complications had previously performed fewer than 20 blocks, we are not able to confirm that a block experience ≤ 20 is a significant risk factor. Faulty image-setting, inability to obtain a view of the needle tip and inadequate supervision are likely to be important risk factors.

[Ultrasound-guided peripheral regional anesthesia : placement and dosage of local anesthetics]. / Ultraschallgesteuerte periphere Regionalanästhesie : Applikationsort und Dosierung des Lokalanästhetikums.

Ever since the use of ultrasound guidance in regional anesthesia became more and more popular in recent years, it seemed obvious that so-called intraneural puncture and injection of local anesthetics was much more common than previously assumed. However, neurologic damage was not seen very often. The ultrasound-guided imaging of the nerves showed that intraneural injection has to be seen as an overall term. This term must be characterized in more detail in accordance with nerve anatomy and morphology. Various studies demonstrated that if intraneural puncture occured the needle usually took a path away from the fascicles (intraneural perifascicular), while intraneural transfascicular puncture seemed relatively rare and intraneural intrafascicular placement of the needle even more uncommon. As long as the needle is placed intraneurally but in an extrafascicular fashion a safe injection and the absence of neurologic damage can be assumed. However, if nerve fascicles are affected neurologic dysfunction can occur. In studies investigating the minimal effective local anesthetic volume needed for successful nerve block, a relevant reduction of injected volume was still achieved by intentionally applying the local anesthetic circumferentially around the outermost nerve layer rather than injecting it into neural structures. As an intraneural -intrafascicular injection carries the risk of nerve injury associated with a decrease in quality of life, the potential of ultrasound guidance in regional anesthesia should be considered. Circumferential administration of local anesthetic rather than creating a single point injection appears to be advantageous.

[Cardioprotection by thoracic epidural anesthesia? : meta-analysis]. / Kardioprotektion durch thorakale Periduralanästhesie? : Metaanalyse.

BACKGROUND: Thoracic epidural analgesia (EDA) is thought to provide cardioprotective effects in patients undergoing noncardiac surgery. The results of two previous meta-analysis showed controversial conclusions regarding the impact of EDA on perioperative survival. The purpose of the present meta-analysis was to evaluate, whether thoracic EDA has the potential to reduce perioperative cardiac morbidity or mortality on the basis of available randomized controlled trials. PATIENTS AND METHODS: A systematic literature search was conducted in medical databases (Med-Line, EBM-Reviews, Embase, Biosis and Biological Abstracts) and relevant clinical trials including patients undergoing noncardiac surgery were evaluated by two independent investigators. All randomized controlled trials investigating the effects of thoracic EDA on perioperative outcome, published from 1980 up to the end of 2008 were included into this quantitative systematic review. Calculations were performed using the statistics program Review Manager 4.1 using a fixed-effects model. RESULTS: Nine studies with a total of 2,768 patients were included in the meta-analysis. Thoracic EDA did not reduce perioperative mortality [odds ratio (Peto OR): 1.08; 95% confidence interval (CI) 0.74-1.58]. Patients receiving thoracic EDA demonstrated a tendency to a lower rate of perioperative myocardial infarction. However, this effect of thoracic EDA did not reach statistical significance (Peto OR: 0.65; 95% CI 0.4-1.05). CONCLUSIONS: The present meta-analysis did not prove any positive influence of thoracic EDA on perioperative in-hospital mortality in patients undergoing noncardiac surgery. Furthermore, it remains questionable if thoracic EDA has the potential to reduce the rate of perioperative myocardial infarction.

The effect of propofol and desflurane anaesthesia on human hepatic blood flow: a pilot study.

This study tested the hypothesis that propofol is associated with a higher hepatic blood flow in humans compared with desflurane. Using a cross over study design, 10 patients received first propofol and then desflurane, and a further 10 patients received desflurane and then propofol. Blood flow index in the right and middle hepatic veins, stroke volume index and cardiac index were assessed by transoesophageal echocardiography. Mean arterial blood pressure, stroke volume index and cardiac index were the same in both groups. Propofol was associated with significantly greater blood flow index in the right hepatic vein (median (IQR [range]) 199 (146-237 [66-388]) vs. 149 (112-189 [42-309]) ml.min(-1).m(-2); p = 0.005) and middle hepatic vein (150 (122-191 [57-341]) vs. 125 (92-149 [47-362]) ml.min(-1).m(-2); p < 0.001) compared with desflurane. In routine clinical conditions, propofol anaesthesia was associated with significantly greater hepatic blood flow than desflurane anaesthesia.

Etomidate reduces glutamate uptake in rat cultured glial cells: involvement of PKA.

BACKGROUND AND PURPOSE: Glutamate is the main excitatory neurotransmitter in the vertebrate CNS. Removal of the transmitter from the synaptic cleft by glial and neuronal glutamate transporters (GLTs) has an important function in terminating glutamatergic neurotransmission and neurological disorders. Five distinct excitatory amino-acid transporters have been characterized, among which the glial transporters excitatory amino-acid transporter 1 (EAAT1) (glutamate aspartate transporter) and EAAT2 (GLT1) are most important for the removal of extracellular glutamate. The purpose of this study was to describe the effect of the commonly used anaesthetic etomidate on glutamate uptake in cultures of glial cells. EXPERIMENTAL APPROACH: The activity of the transporters was determined electrophysiologically using the whole cell configuration of the patch-clamp recording technique. KEY RESULTS: Glutamate uptake was suppressed by etomidate (3-100 microM) in a time- and concentration-dependent manner with a half-maximum effect occurring at 2.4+/-0.6 microM. Maximum inhibition was approximately 50% with respect to the control. Etomidate led to a significant decrease of V(max) whereas the K(m) of the transporter was unaffected. In all cases, suppression of glutamate uptake was reversible within a few minutes upon washout. Furthermore, both GF 109203X, a nonselective inhibitor of PKs, and H89, a selective blocker of PKA, completely abolished the inhibitory effect of etomidate. CONCLUSION AND IMPLICATIONS: Inhibition of glutamate uptake by etomidate at clinically relevant concentrations may affect glutamatergic neurotransmission by increasing the glutamate concentration in the synaptic cleft and may compromise patients suffering from acute or chronic neurological disorders such as CNS trauma or epilepsy.

[Left ventricular diastolic dysfunction. Implications for anesthesia and critical care]. / Linksventrikuläre diastolische Dysfunktion. Bedeutung in Anästhesie und Intensivmedizin.

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.

An unusual case of early fulminant post-traumatic fat embolism syndrome.

A multiple-injured patient developed a very early onset fulminant fat embolism syndrome that was partially masked by haemorrhagic shock. Despite early diagnosis by transoesophageal echocardiography and aggressive symptomatic treatment, there was a rapid evolution to death. Post mortem examination revealed the presence of both pulmonary and systemic fat emboli. This case highlights the ever present risk of masked fat embolism syndrome shortly after trauma.

Noninvasive diagnosis of coronary artery disease: a comparison between cardiokymographic and electrocardiographic stress testing.

Noninvasive cardiokymography has been further developed to be able to record wall motion abnormalities during exercise. The study was designed to evaluate the diagnostic accuracy of stress cardiokymography and electrocardiography in the diagnosis of coronary artery disease. 223 patients were included in a prospective investigation using a newly developed computerized cardiokymography device. Sensitivity, specificity, and positive predictive value were 61, 69 and 90% for exercise cardiokymography, and 57, 74 and 91% for exercise electrocardiography, respectively. There was no statistically significant difference between cardiokymography and electrocardiography. The combination of electrocardiography and cardiokymography did not produce a significant improvement in diagnostic accuracy in comparison to exercise electrocardiography alone.

Is it feasible to monitor total hepatic blood flow by use of transesophageal echography? An experimental study in pigs.

OBJECTIVES: Total hepatic venous blood flow is determined by the common hepatic arterial blood flow and the venous outflow from stomach, spleen, pancreas, small intestine, and bowel, collected by the portal vein, and thus represents overall splanchnic perfusion. We investigated whether transesophageal echography (TEE) can provide a method for bedside assessment of hepatic venous blood flow useful as a noninvasive method for measuring splanchnic perfusion in clinical practice. DESIGN AND SETTING: Experimental study in 15 anesthetized and ventilated pigs in an animal research laboratory. INTERVENTIONS: TEE-derived calculations of hepatic venous blood flow were compared with liver blood flow measurements using perivascular ultrasound flow probes surgically positioned on portal vein and common hepatic artery. Parameters were determined at baseline and after modulating splanchnic perfusion by either PEEP maneuver (15 cmH2O) or intravenous epinephrine (0.1 microgram kg-1 min-1). MEASUREMENTS AND RESULTS: Diameter (d) and velocity time integral (VTI) of all three hepatic veins were determined by TEE, heart rate (HR) was derived from electrocardiography and flow subsequently calculated as Q = pi.(d/2)(2).0.57.VTI.HR. Regression analysis of matched TEE and flow probe values showed a significant linear relationship (r2 = 0.698). Bias analysis revealed a systematic underestimation of liver blood flow by TEE, possibly due to use of 0.57 as correction factor for mean velocity, while changes in liver blood flow were reliably detected. CONCLUSION: TEE offers a noninvasive approach for monitoring hepatic perfusion and may be used in patients.

Electrocardiographic exercise stress testing for cardiac risk assessment in patients undergoing noncardiac surgery.

BACKGROUND: The value of exercise electrocardiography in the prediction of perioperative cardiac risk has yet to be defined. This study was performed to determine the predictive value of exercise electrocardiography as compared with clinical parameters and resting electrocardiography. METHODS: A total of 204 patients at intermediate risk for cardiac complications prospectively underwent exercise electrocardiography before noncardiac surgery. Of these, 185 were included in the final evaluation. All patients underwent follow-up evaluation postoperatively by Holter monitoring for 2 days, daily 12-lead electrocardiogram, and creatine kinase, creatine kinase MB, and troponin-T measurements for 5 days. Cardiac events were defined as cardiac death, myocardial infarction, minor myocardial cell injury, unstable angina pectoris, congestive heart failure, and ventricular tachyarrhythmia. Potential risk factors for an adverse event were identified by univariate and multivariate logistic regression analysis. RESULTS: Perioperative cardiac events were observed in 16 patients. There were 6 cases of myocardial infarction and 10 cases of myocardial cell injury. The multivariate correlates of adverse cardiac events were definite coronary artery disease (odds ratio, 8.8; 95% confidence interval [CI], 1.1--73.1; P = 0.04), major surgery (odds ratio, 4.7; 95% CI, 1.3--16.3; P = 0.02), reduced left ventricular performance (odds ratio, 2.0; 95% CI, 1.1--3.8; P = 0.03), and ST-segment depression of 0.1 mV or more in the exercise electrocardiogram (odds ratio, 5.2; 95% CI, 1.5--18.5; P = 0.01). A combination of clinical variables and exercise electrocardiography improved preoperative risk stratification. CONCLUSIONS: This prospective study shows that a ST-segment depression of 0.1 mV or more in the exercise electrocardiogram is an independent predictor of perioperative cardiac complications.

Use of multi-plane transoesophageal echocardiography in visualization of the main hepatic veins and acquisition of Doppler sonography curves. Comparison with the transabdominal approach.

The role of multi-plane transoesophageal echocardiography (TOE) in the visualization of the three main hepatic veins and acquisition of Doppler sonography curves has not been established. We have studied this diagnostic option of TOE in 34 patients during general anaesthesia. The findings were compared with the results of conventional transabdominal sonography (TAS). Using TOE, each of the three main hepatic veins could be visualized in all patients. In contrast, TAS allowed adequate two-dimensional visualization of the right, middle, and left hepatic vein in only 97%, 85%, and 61% of the patients, respectively. Adequate Doppler tracings of the right and middle hepatic vein could be obtained in 100% and 97% of the patients by TOE and in 91% and 50% of the patients by TAS. Doppler tracings of the left hepatic vein could only be acquired in 18% of the patients by TOE, but in 47% of the patients by TAS. As blood flow may be calculated from the diameter of the vessel, velocity time integral of the Doppler curve and heart rate, TOE may provide an interesting non-invasive tool to monitor blood flow in the right and middle hepatic vein.

[Importance of acute PTCA in the treatment of perioperative myocardial infarction]. / Bedeutung der Akut-PTCA in der Therapie des perioperativen Myokardinfarkts.

The mortality of perioperative myocardial infarction is still high and according to recently published data amounts to 17 to 42%. In the seventies introduction of thrombolytic therapy has led to a dramatic reduction in mortality of non-perioperative myocardial infarction. However, in the perioperative situation thrombolytic therapy remains to be problematic in most cases because of expected severe bleeding complications. In the last 4-6 years acute-PTCA has been established in the therapy of acute myocardial infarction. Up to date no data are available concerning the effect of acute-PTCA on mortality of perioperative myocardial infarction. Nevertheless it can be assumed, that acute-PTCA will lead to a considerable reduction in mortality of perioperative myocardial infarction. Therefore, in patients with significant perioperative myocardial infarction immediate coronary angiography and, if indicated, acute-PTCA should be performed. In principle, thrombolytic therapy is considered to be contraindicated in the intra- or postoperative situation. However, if coronary angiography and PTCA are not possible, thrombolysis might be taken into consideration, in particular if the expected bleeding complications are small in relation to the expected benefit of thrombolysis. Since acute-PTCA has been shown to remarkably reduce mortality in patients with cardiogenic shock after acute myocardial infarction, this group of patients should be especially considered.

[The basics of catecholamine therapy. 2. A guide to clinical use]. / Grundsätze der Katecholamintherapie. Teil 2: Leitfaden der klinischen Anwendung.

Myocardial function is determined by preload, afterload, contractility and heart rate. Pathologic changes of these variables may result in decrease of blood pressure, acute heart failure or cardiogenic shock. Hyperdynamic septic shock is associated with systemic hypotension despite increased cardiac output. Mediators of sepsis induce both myocardial depression and pulmonary arterial hypertension. Moreover, sepsis is characterized by microcirculatory disturbances and dysbalance in regional oxygen delivery and consumption. Severe systemic hypotension is a symptom often requiring catecholamine therapy to restore systemic circulation and to avoid organ damage. As the use of catecholamines is not a causal therapy administration should be limited to an initial measure until correction of the underlying abnormalities can be achieved. Different etiologies of shock as well as diseases requiring specific interventions as pulmonary embolectomy, systemic lysis or coronary angioplasty have to be considered. First line intervention consists of optimizing preload by fluid resuscitation as appropriate and use of dopamine (4-12 micrograms/kg.min) as primary catecholamine to increase contractility and blood pressure. In acute left heart failure inotropic support with dobutamine (4-12 micrograms/kg.min) or epinephrine (0.05-1 microgram/kg.min) may be necessary, frequently combined with a vasodilator (sodium nitroprusside 0.2-5 micrograms/kg.min or nitroglycerine 0.5-2.5 micrograms/kg.min) or phosphodiesterase-III-inhibitor (milrinone 0.3-0.8 microgram/kg.min). In right heart failure norepinephrine is preferred to increase coronary perfusion pressure. Hyperdynamic septic shock with decreased vascular resistance is treated with norepinephrine to restore mean arterial pressure and to improve right ventricular dysfunction induced by pulmonary hypertension.

[Principles of catecholamine therapy. 1. Characterization of clinically relevant sympathomimetics]. / Grundsätze der Katecholamintherapie. Teil 1: Charakterisierung der therapeutisch bedeutsamen Sympathomimetika.

All involuntary innervated structures of the body are controlled by the sympathetic and parasympathetic nervous system. Adrenaline, noradrenaline and dopamine are endogenous catecholamines binding to adrenergic and dopaminergic receptors, respectively, to mediate their clinical effects. Adrenoceptors are classified as alpha 1, alpha 2, beta 1 and beta 2 subtypes which were even further subcharacterized the recent years. Adrenoceptors are membrane proteins interacting with the agonist and, thus, inducing G-protein mediated intracellular effects. Adrenaline induces an extensive increase of heart rate and stroke volume mediated by beta-adrenoceptors and significantly enhances peripheral vascular resistance by alpha-adrenoceptor stimulation, when administered beyond 0.1 microgram/kg.min. In contrast, the clinical effects of noradrenaline are predominantly characterized by alpha-adrenoceptor stimulation resulting in a less pronounced increase of heart rate. Dopamine, less potent on adrenoceptors, shows additional effects on renal as well as on splanchnic circulation mediated by dopaminergic receptors. Dobutamine, primarily acting on beta-adrenoceptors, results in positive inotropic effects without an increase in vascular resistance. Dopexamine, a synthetic catecholamine, induces vasodilation via beta 2-adrenoceptor stimulation and potentially increases splanchnic blood flow by additional effects on dopaminergic receptors. Isoproterenol, the classical beta-adrenoceptor agonist, mediates positive inotropic effects and causes a major increase in heart rate and a significant decrease of systemic vascular resistance. Independent on adrenoceptors, phosphodiesterase-III-inhibitors exert positive inotropic and vasodilating activity by an increase in intracellular cAMP concentration induced by inhibition of cAMP hydrolysis.

Perioperative transcutaneous pacemaker in patients with chronic bifascicular block or left bundle branch block and additional first-degree atrioventricular block.

BACKGROUND: Complete heart block is dreaded perioperatively in patients with chronic bifascicular or left bundle branch block (LBBB) and additional first-degree A-V block. Our aim was to investigate the necessity as well as the efficacy and safety of transcutaneous pacing in the perioperative setting. METHODS: Thirty-nine consecutive patients with asymptomatic chronic bifascicular block or LBBB and prolongation of the P-R interval scheduled to undergo surgery under anesthesia were prospectively enrolled in the study. Preoperatively, a transcutaneous pacemaker (PACE 500 D, Osypka Co.) was applied; its efficacy was checked with intra-arterial blood pressure measurement; the pain level was recorded. Additionally, 24-h Holter monitoring (CM2, CM5) was applied. Occurrences of a block progression or a bradycardia of <40 beats/min with hemodynamic impairment were the defined end points. RESULTS: Thirty-seven of the 39 patients (95%) could be successfully stimulated with a median current strength of 70 mA; whereby 33 of the 39 patients felt moderate to severe pain. There was no perioperative block progression. Three cases of brady-cardia of <40 beats/min with a critical drop in blood pressure occurred; but these patients were successfully treated with drug therapy without pacemaker stimulation. CONCLUSION: The perioperative application and testing of the pacemaker was safe and could be performed in nearly all patients successfully. However, we do not consider a routine prophylactic transcutaneous placement in patients with chronic bifascicular or LBBB and additional first-degree A-V block justified. Nevertheless, appropriate drugs and temporary pacemaker equipment should be easily accessible.

The effect of i.v. enalaprilat in chronically treated hypertensive patients during cardiac surgery.

BACKGROUND: Angiotensin-converting enzyme (ACE) inhibitors are well established as long-term antihypertensives and have also been proved useful in hypertensive emergencies. Therefore, we investigated whether intraoperative i.v. enalaprilat may reduce the incidence of perioperative hypertensive reactions in coronary artery bypass grafting (CABG). METHODS: Thirty-eight male patients chronically treated for arterial hypertension and scheduled for CABG randomly and double-blindly received either enalaprilat 30 micrograms.kg-1 or NaCl 0.9% at the time of skin incision. Intraoperatively, increases of mean arterial pressure (MAP) > 85 mmHg or > 80 mmHg during cardiopulmonary bypass (CPB) were treated by an urapidil bolus. The total intraoperative amount of urapidil was documented for both groups. Systemic and pulmonary hemodynamics as well as the plasma levels of epinephrine, norepinephrine, arginine vasopressin and renin were measured intraoperatively and up to 2 h after admission to the intensive care unit. RESULTS: Mean arterial pressure, cardiac index and systemic vascular resistance did not differ between the enalaprilat and the control group. Renin plasma levels significantly increased after infusion of enalaprilat and did not change in the placebo group. Catecholamine and arginine vasopressin plasma levels increased significantly during CPB and remained high in the postoperative period without any intergroup difference. The same amount of urapidil had to be given in the two groups to maintain MAP below the defined limit. CONCLUSION: We conclude that infusing 30 micrograms.kg-1 enalaprilat in patients chronically treated for arterial hypertension does not prevent hypertensive reactions during CABG.

Perioperative risk of bradyarrhythmias in patients with asymptomatic chronic bifascicular block or left bundle branch block: does an additional first-degree atrioventricular block make any difference?

BACKGROUND: The incidence of perioperative bradyarrhythmias in patients with bifascicular or left bundle branch block (LBBB) and the influence of an additional first-degree atrioventricular (A-V) block has not been evaluated with 24-h Holter electrocardiographic monitoring. Therefore the authors assessed the rate of block progression and bradyarrhythmia in these patients. METHODS: Patients (n = 106) with asymptomatic bifascicular block or LBBB with or without an additional first-degree A-V block scheduled for surgery under general or regional anesthesia were enrolled prospectively. Three patients were excluded. Of the 103 remaining, 56 had a normal P-R interval and 47 had a prolonged one. Holter monitoring (CM2, CM5) was applied to each patient just before induction of anesthesia and was performed for 24 h. The primary endpoint of the study was the occurrence of block progression. As secondary endpoints, bradycardias < 40 beats/min with hemodynamic compromise (systolic blood pressure < 90 mmHg) or asystoles > 5 s were defined. RESULTS: Block progression to second-degree A-V block and consecutive cardiac arrest occurred in one case of LBBB without a prolonged P-R interval Severe bradyarrhythmias with hypotension developed in another eight patients: asystoles > 5 s occurred in two cases and six patients had bradycardias < 40/min. Pharmacotherapy was successful in these eight patients. There was no significant difference for severe bradyarrhythmias associated with hemodynamic compromise between patients with and without P-R prolongation (P = 1.00). CONCLUSIONS: In patients with chronic bifascicular block or LBBB, perioperative progression to complete heart block is rare. However, the rate of bradyarrhythmias with hemodynamic compromise proved to be relevant. Because an additional first-degree A-V block did not increase the incidence of severe bradyarrhythmias and pharmacotherapy by itself was successful in nearly all cases, routine prophylactic insertion of a temporary pacemaker in such patients should be questioned.

Cardiac function in patients with treated hypertension during aortic aneurysm repair.

OBJECTIVES: To investigate the impact of arterial hypertension on cardiac function during aortic cross-clamping and declamping. DESIGN: Prospective study. SETTING: University hospital. PARTICIPANTS: Twenty treated hypertensive males with slight left ventricular hypertrophy and 10 normotensive controls undergoing elective repair of an abdominal aortic aneurysm. INTERVENTIONS: Using transesophageal echocardiography, the mitral inflow profile was evaluated during aortic cross-clamping and declamping. MEASUREMENTS AND MAIN RESULTS: During the clamping period, the ratio of peak atrial to peak early filling velocity (PA/PE) was significantly higher in the hypertensive patients. One minute after aortic cross-clamping, mean arterial pressure (MAP) and pulmonary artery occlusion pressure significantly increased in the hypertensive patients, whereas they did not change in the normotensive group. Cardiac index and heart rate significantly decreased after cross-clamping, and increased after clamp release in both groups. PA/PE significantly dropped in both groups after aortic declamping, and returned to baseline values thereafter. MAP also decreased significantly in both groups after clamp release, but the fall of MAP tended to be more pronounced in the hypertensive patients. CONCLUSIONS: In the treated hypertensive patients, more pronounced hemodynamic and echocardiographic responses to aortic cross-clamping probably mirror the altered diastolic left ventricular function in these patients. With respect to intraoperative management, however, the treated hypertensive patients did not react grossly differently from the normotensive controls.

[Abdominal complications following heart surgery]. / Abdominelle Komplikationen nach kardiochirurgischen Eingriffen.

OBJECTIVE: Intra-abdominal complications occurring after cardiopulmonary bypass operations are rare but often fatal. There are only speculative approaches concerning the pathogenesis and the risk factors of these complications. The aim of our study was therefore to determine the causative factors and to evaluate the diagnostic and therapeutic measures, because early diagnosis and immediate treatment is essential for the outcome of the patients. DESIGN: 500 consecutive patients who underwent cardiopulmonary bypass procedures over a period of 14 months were examined for intra-abdominal complications. The records of these patients were reviewed in relation to possible risk factors and the group with intra-abdominal complications was compared with a random sample of 50 patients in respect of possible risk factors. The diagnostic procedures (serum lactate concentrations, sigmoidoscopy, coloscopy) and the therapeutic interventions were also evaluated. MAIN RESULTS: 9 (1.8%) of the 500 patients developed intra-abdominal complications. The mortality rate was 44% (4 of 9). 5 patients had bowel necrosis or ischaemic colitis. Pseudo-obstruction appeared in 5 cases. One patient developed cholecystitis and one acute haemorrhagic pancreatitis. Gastroduodenal complications were not observed. There was no difference between the group with intra-abdominal complications and the random sample with regard to sex, type of operation and preoperative intra-abdominal diseases. Clinical risk factors identified were: age, occlusive vascular disease, atrial fibrillation, prolonged aortic cross-clamping times and mean bypass times, intraoperative and postoperative need for supply of epinephrine and norepinephrine, implantation of an intraaortic balloon counterpulsation pump, low cardiac output, postoperative multiple organ failure. 8 out of the 9 patients had severe intraoperative surgical complications or general complications in the postoperative course. All patients with bowel necrosis or ischaemic colitis had abnormal serum lactate concentrations. With the aid of sigmoidoscopy in one patient, only bowel necrosis or ischaemic colitis could be detected. In one patient with pseudoobstruction, an operation was probably obviated by decompression of the colon by coloscopy. 6 of the 500 patients after cardiopulmonary bypass required emergency laparotomy. Two patients with bowel necrosis were saved by early hemicolectomy. CONCLUSION: In reviewing both our results and data cited in earlier studies, intra-abdominal complications can generally be attributed to the following: Intraoperative surgical complications with the consequence of prolonged aortic cross clamping and total bypass times can cause low cardiac output and mesenteric hypoperfusion. Predominantly as a result of the low cardiac output, the use of vasopressors increases splanchnic ischaemia, in particular in patients with pre-existing occlusive vascular disease of the mesenteric arteries. Mucosal ischaemia might be aggravated by a concurrent pseudo-obstruction. On the other hand, intraoperative complications and low cardiac output can cause further complications and finally multiple organ failure. Multiple organ failure and ischaemia of the gut can initiate the vicious circle which is responsible for the high mortality from these complications. Early detection by careful physical examination and the combination of the diagnostic procedures and prompt treatment should lead to a reduction of mortality.