Calcium supplementation during trauma resuscitation: a propensity score-matched analysis from the TraumaRegister DGU®.

BACKGROUND: In major trauma patients, hypocalcemia is associated with increased mortality. Despite the absence of strong evidence on causality, early calcium supplementation has been recommended. This study investigates whether calcium supplementation during trauma resuscitation provides a survival benefit. METHODS: We conducted a retrospective analysis using data from the TraumaRegister DGU® (2015-2019), applying propensity score matching to balance demographics, injury severity, and management between major trauma patients with and without calcium supplementation. 6 h mortality, 24 h mortality, and in-hospital mortality were considered as primary outcome parameters. RESULTS: Within a cohort of 28,323 directly admitted adult major trauma patients at a European trauma center, 1593 (5.6%) received calcium supplementation. Using multivariable logistic regression to generate propensity scores, two comparable groups of 1447 patients could be matched. No significant difference in early mortality (6 h and 24 h) was observed, while in-hospital mortality appeared higher in those with calcium supplementation (28.3% vs. 24.5%, P = 0.020), although this was not significant when adjusted for predicted mortality (P = 0.244). CONCLUSION: In this matched cohort, no evidence was found for or against a survival benefit from calcium supplementation during trauma resuscitation. Further research should focus on understanding the dynamics and kinetics of ionized calcium levels in major trauma patients and identify if specific conditions or subgroups could benefit from calcium supplementation.

Trauma-induced disturbances in ionized calcium levels correlate parabolically with coagulopathy, transfusion, and mortality: a multicentre cohort analysis from the TraumaRegister DGU®.

BACKGROUND: To which extent trauma- induced disturbances in ionized calcium (iCa2+) levels have a linear relationship with adverse outcomes remains controversial. The goal of this study was to determine the association between the distribution and accompanying characteristics of transfusion-independent iCa2+ levels versus outcome in a large cohort of major trauma patients upon arrival at the emergency department. METHODS: A retrospective observational analysis of the TraumaRegister DGU® (2015-2019) was performed. Adult major trauma patients with direct admission to a European trauma centre were selected as the study cohort. Mortality at 6 h and 24 h, in-hospital mortality, coagulopathy, and need for transfusion were considered as relevant outcome parameters. The distribution of iCa2+ levels upon arrival at the emergency department was calculated in relation to these outcome parameters. Multivariable logistic regression analysis was performed to determine independent associations. RESULTS: In the TraumaRegister DGU® 30 183 adult major trauma patients were found eligible for inclusion. iCa2+ disturbances affected 16.4% of patients, with hypocalcemia (< 1.10 mmol/l) being more frequent (13.2%) compared to hypercalcemia (≥ 1.30 mmol/l, 3.2%). Patients with hypo- and hypercalcemia were both more likely (P < .001) to have severe injury, shock, acidosis, coagulopathy, transfusion requirement, and haemorrhage as cause of death. Moreover, both groups had significant lower survival rates. All these findings were most distinct in hypercalcemic patients. When adjusting for potential confounders, mortality at 6 h was independently associated with iCa2+ < 0.90 mmol/L (OR 2.69, 95% CI 1.67-4.34; P < .001), iCa2+ 1.30-1.39 mmol/L (OR 1.56, 95% CI 1.04-2.32, P = 0.030), and iCa2+ ≥ 1.40 mmol/L (OR 2.87, 95% CI 1.57-5.26; P < .001). Moreover, an independent relationship was determined for iCa2+ 1.00-1.09 mmol/L with mortality at 24 h (OR 1.25, 95% CI 1.05-1.48; P = .0011), and with in-hospital mortality (OR 1.29, 95% CI 1.13-1.47; P < .001). Both hypocalcemia < 1.10 mmol/L and hypercalcemia ≥ 1.30 mmol/L had an independent association with coagulopathy and transfusion. CONCLUSIONS: Transfusion-independent iCa2+ levels in major trauma patients upon arrival at the emergency department have a parabolic relationship with coagulopathy, need for transfusion, and mortality. Further research is needed to confirm whether iCa2+ levels change dynamically and are more a reflection of severity of injury and accompanying physiological derangements, rather than an individual parameter that needs to be corrected as such.

The first hour of trauma reception is critical for patients with major thoracic trauma: A retrospective analysis from the TraumaRegister DGU.

BACKGROUND: Up to 25% of trauma deaths are related to thoracic injuries. OBJECTIVE: The primary goal was to analyse the incidence and time distribution of death in adult patients with major thoracic injuries. The secondary goal was to determine if potentially preventable deaths occurred within this time distribution and, if so, identify an associated therapeutic window. DESIGN: Retrospective observational analysis. SETTING: TraumaRegister DGU. PATIENTS: Major thoracic injury was defined as an Abbreviated Injury Scale (AIS) 3 or greater. Patients with severe head injury (AIS ≥ 4) or injuries to other body regions with AIS being greater than the thoracic injury (AIS other >AIS thorax) were excluded to ensure that the most severe injury described was primarily thoracic related. MAIN OUTCOME MEASURES: Incidence and time distribution of mortality were considered the primary outcome measures. Patient and clinical characteristics and resuscitative interventions were analysed in relation to the time distribution of death. RESULTS: Among adult major trauma cases with direct admission from the accident scene, 45% had thoracic injuries and overall mortality was 9.3%. In those with major thoracic trauma ( n  = 24 332) mortality was 5.9% ( n  = 1437). About 25% of these deaths occurred within the first hour after admission and 48% within the first day. No peak in late mortality was seen. The highest incidences of hypoxia and shock were seen in non-survivors with immediate death within 1 h and early death (1 to 6 h). These groups received the largest number of resuscitative interventions. Haemorrhage was the leading cause of death in these groups, whereas organ failure was the leading cause of death amongst those who survived the first 6 h after admission. CONCLUSION: About half of adult major trauma cases had thoracic injuries. In non-survivors with primarily major thoracic trauma, most deaths occurred immediately (<1h) or within the first 6 h after injury. Further research should analyse if improvements in trauma resuscitation performed within this time frame will reduce preventable deaths. TRIAL REGISTRATION: The present study is reported within the publication guidelines of the TraumaRegister DGU® and registered as TR-DGU project ID 2020-022.

The relationship between pulmonary artery acceleration time and mean pulmonary artery pressure in patients undergoing cardiac surgery: An observational study.

BACKGROUND: A noninvasive method of estimating pulmonary arterial pressures is required, as the use of the pulmonary artery catheter (PAC) is decreasing in cardiac anaesthesia. Pulmonary hypertension is defined as a mean pulmonary artery pressure (MPAP) at least 25 mmHg and this can be estimated echocardiographically by measuring the pulmonary acceleration time (PAT). This relationship has not been validated when measured using transoesophageal echocardiography (TOE) in anaesthetised patients having cardiac surgery. OBJECTIVE: We hypothesised that there was a quantifiable relationship between PAT and MPAP. We aimed to assess this relationship in cardiac surgical patients undergoing general anaesthesia with TOE. DESIGN: An observational study. SETTING: Catholic University Hospital, Leuven, Belgium, between August and December 2013. PATIENTS: Ninety-eight patients having cardiac surgery, where intraoperative TOE was used and a PAC was inserted as part of routine care. INTERVENTIONS: Nil. MAIN OUTCOME MEASURES: PAT and MPAP were measured simultaneously with TOE and the PAC and this relationship was assessed. RESULTS: PAT and MPAP measurements were possible in all patients. There was a curvilinear relationship between PAT and MPAP with a PAT of less than 107 ms detecting pulmonary hypertension with a sensitivity of 75% and a specificity of 94.8%. The area under the receiver operating characteristic (ROC) curve was 0.87 [95% confidence interval (95% CI) 0.80 to 0.95]. Below a PAT of 107 ms, the relationship was relatively linear and could be described by the equation MPAP (mmHg) = 77 -  (0.49 x PAT). Ninety-five percent of the pressures estimated by this equation are within ±13.8 mmHg of the measured pressure. CONCLUSION: Estimation of PAT with TOE in anaesthetised cardiac surgical patients is possible. PAT is good at discriminating between patients with and without pulmonary hypertension, with a cut-off of less than 107 ms detecting pulmonary hypertension with a sensitivity of 75% and specificity of 94.8%.

Anesthetic Management for Resection of Bilateral Pulmonary Artery Sarcoma.

We describe a patient who presented with a bilateral pulmonary artery sarcoma, initially treated as pulmonary embolism, that necessitated concomitant pulmonary endarterectomy and pneumonectomy. We reviewed the anesthetic management used for this procedure, which bears many similarities to the management of patients undergoing pulmonary thromboendarterectomy. Right ventricular failure, pulmonary hemorrhage, and cerebral ischemia due to circulatory arrest are life-threatening perioperative complications. The anesthesiologist can play a key role in the prevention (or timely recognition and treatment) of these perioperative complications by establishing adequate hemodynamic, echocardiographic, and neurologic monitoring and by optimizing cardiopulmonary function and coagulation.

Noninvasive estimation of left atrial pressure with transesophageal echocardiography.

BACKGROUND: The pulmonary artery catheter (PAC) has historically been used to measure cardiac filling pressures of which pulmonary capillary wedge pressure (PCWP) has been used as a surrogate of left atrial pressure (LAP) and left ventricular end-diastolic pressure. Increasingly, the use of the PAC has been questioned in the perioperative period with multiple large studies unable to clearly demonstrate benefit in any group of patients, resulting in a declining use in the perioperative period. Alternative methods for the noninvasive estimation of left-sided filling pressures are required. Echocardiography has been used to provide noninvasive estimation of PCWP and LAP, based on evaluating mitral inflow velocity with the E and A waves and looking at movement of the mitral annulus with tissue Doppler (e'). AIM: The aim of our study was to assess the relationship between PCWP and E/e' in cardiac surgical patients with transesophageal echocardiography (TOE). DESIGN: A prospective observational study. SETTING: Cardiac surgical patients in a single quaternary referral university teaching hospital. METHODS: The ratio of mitral inflow velocity (E wave) to mitral annular tissue velocity (e') (the E/e' ratio) and PCWP of 91 patients undergoing general anesthesia and cardiac surgery were simultaneously recorded, with the use of TOE and a PAC. RESULTS: The correlation between E/e' and PCWP was modest with a Spearman rank correlation coefficient of 0.29 (P = 0.005). The area under the receiver operating characteristic curve for using E/e' to predict elevated PCWP (≥18 mmHg) was 0.6825 (95% confidence interval: 0.57-0.80), indicating some predictive utility. The optimum threshold value of E/e' was 10 which had 71% sensitivity and 60% specificity to predict a PCWP ≥18 mmHg. CONCLUSIONS: Noninvasive measurements of E/e' in general cardiac surgical patients have only a modest correlation and does not reliably estimate PCWP.

Pneumoperitoneum Does Not Influence Spread of Local Anesthetics in Midaxillary Approach Transversus Abdominis Plane Block: A Descriptive Cadaver Study.

BACKGROUND AND OBJECTIVES: The transversus abdominis plane (TAP) block can be used as part of a multimodal analgesia protocol after abdominal surgery. This study investigated whether a pneumoperitoneum during abdominal surgery influences the spread of local anesthetics. METHODS: Nine fresh frozen cadavers were used for the study. Using an ultrasound-guided midaxillary technique, a unilateral TAP block-like injection with 20 mL of methylene blue dye was performed. After the injection, a pneumoperitoneum was immediately installed for 1 hour. After desufflation, this ipsilateral side was dissected, and a TAP block-like injection was performed on the contralateral side. One hour after injection, the contralateral side was also dissected. The anatomical dissection was used to determine the extent of dye spread and the nerves stained by the dye. RESULTS: In none of the specimens did the dye reach the posterior origin of the transverse abdominal muscle. There was no statistically significant difference in the number of stained nerves and spread of the dye in the insufflated side compared with the noninsufflated side. In 4 of 9 cadavers, we found a variant course of a nerve preventing staining of that nerve. CONCLUSIONS: The stretch of the abdominal wall caused by the insufflation of the abdomen does not influence the spread of dye in the abdominal wall. Because of the absence of posterior spread, regardless of the timing of a midaxillary ultrasound-guided approach, we believe that a posterior approach should be chosen if posterior spread is desired.

Regional anesthesia outside the operating room: indications and techniques.

PURPOSE OF REVIEW: Regional anesthesia is not only performed in the operating room. There are indications for the use of these techniques for pain relief in the emergency department and for anesthesia support of procedures outside the operating room. In this review, we will provide an overview of the indications for the regional techniques performed in the out-of-operating room environment. RECENT FINDINGS: In the emergency department, patients may experience significant pain, and adequate analgesia is not always provided. Regional analgesia is effective and indicated for many trauma situations including hip fracture, reduction of shoulder dislocation, treatment of upper limb fractures and multiple rib fractures.Ultrasound guidance makes the performance of regional blocks more accessible and safer for use in the emergency department setting.For therapeutic procedures outside the operating room, regional anesthesia is possible for uterine artery embolization and for postoperative analgesia after implantation of cervical brachytherapy needles. SUMMARY: Regional anesthesia is a valuable option for analgesia in trauma patients, enabling improved pain control in the emergency department and has benefits in the anesthetic management of therapeutic procedures outside the operating room. For many blocks, ultrasound guidance is useful.

Thoracic epidural anaesthesia disrupts the protective mechanism of homeometric autoregulation during right ventricular pressure overload by cardiac sympathetic blockade: a randomised controlled animal study.

CONTEXT: Thoracic epidural anaesthesia (TEA) is increasingly used in high-risk surgical patients. We recently demonstrated that TEA-mediated cardiac sympathicolysis prevents the native right ventricular positive inotropic response to the induction of acute pulmonary hypertension. OBJECTIVES: In this subsequent study, we induced a selective TEA after acute pulmonary hypertension had been established. We hypothesised that TEA in these circumstances would also exert negative inotropic effects on the right ventricle, not being mediated by possible effects on vasotonus, right ventricular coronary flow dynamics or right ventricular oxygen balance. DESIGN: Randomised placebo-controlled animal study. SETTING: University hospital animal laboratory. INTERVENTIONS: Eighteen pigs were instrumented with an epidural catheter at the thoracic or lumbar level, a right ventricular pressure-volume catheter, transonic flow probes around the pulmonary artery and the right coronary artery, a pressure catheter in the pulmonary artery and a 22-G catheter within a right ventricular free wall coronary vein. Right ventricular pressure overload was induced by constricting the pulmonary artery. After haemodynamic stabilisation, animals were then assigned to receive TEA (n = 6, 1 ml bupivacaine 0.5%), lumbar epidural anaesthesia (LEA) (n = 6, 4 ml bupivacaine 0.5%) or control (n = 6, isotonic saline). The extent of the sympathetic block was assessed by thermography. Final measurements were performed 30 min after the induction of epidural anaesthesia. RESULTS: Pulmonary artery constriction increased pulmonary artery effective elastance and right ventricular contractility in all groups. TEA caused a sympathetic block ranging from C6 to T6, whereas LEA caused a block from T13 to L5. TEA decreased right ventricular contractility (1.5 ± 0.6 vs. 3.2 ± 0.9 mW s ml(-1)) and cardiac output (1.8 ± 0.3 vs. 2.4 ± 0.3 l min(-1)), although systemic vascular resistance was unaffected. In the LEA group, systemic vascular resistance decreased, but right ventricular contractility remained unchanged. Right ventricular coronary flow, oxygen delivery and consumption were comparable between the groups. CONCLUSION: During acute pulmonary hypertension, selective blockade of cardiac sympathetic nerves by TEA acutely abolished the protective adaptation of right ventricular contractility to right ventricular pressure overload and deteriorated systemic haemodynamics. This effect was attributable solely to the depression of right ventricular contractility and was neither the result of impaired right ventricular coronary flow dynamics nor of systemic vasodilation.

Effects of inhaled iloprost on right ventricular contractility, right ventriculo-vascular coupling and ventricular interdependence: a randomized placebo-controlled trial in an experimental model of acute pulmonary hypertension.

INTRODUCTION: Prostacyclin inhalation is increasingly used to treat acute pulmonary hypertension and right ventricular failure, although its pharmacodynamic properties remain controversial. Prostacyclins not only affect vasomotor tone but may also have cAMP-mediated positive inotropic effects and modulate autonomic nervous system tone. We studied the role of these different mechanisms in the overall haemodynamic effects produced by iloprost inhalation in an experimental model of acute pulmonary hypertension. METHODS: In this prospective, randomized, placebo-controlled animal study, twenty-six pigs (mean weight 35 +/- 2 kg) were instrumented with biventricular conductance catheters, a pulmonary artery flow probe and a high-fidelity pulmonary artery pressure catheter. The effects of inhaled iloprost (50 microg) were studied in the following groups: animals with acute hypoxia-induced pulmonary hypertension, and healthy animals with and without blockade of the autonomic nervous system. RESULTS: During pulmonary hypertension, inhalation of iloprost resulted in a 51% increase in cardiac output compared with placebo (5.6 +/- 0.7 versus 3.7 +/- 0.8 l/minute; P = 0.0013), a selective reduction in right ventricular afterload (effective pulmonary arterial elastance: 0.6 +/- 0.3 versus 1.2 +/- 0.5 mmHg/ml; P = 0.0005) and a significant increase in left ventricular end-diastolic volume (91 +/- 12 versus 70 +/- 20 ml; P = 0.006). Interestingly, right ventricular contractility was reduced after iloprost-treatment (slope of preload recruitable stroke work: 2.2 +/- 0.5 versus 3.4 +/- 0.8 mWatt.s/ml; P = 0.0002), whereas ventriculo-vascular coupling remained essentially preserved (ratio of right ventricular end-systolic elastance to effective pulmonary arterial elastance: 0.97 +/- 0.33 versus 1.03 +/- 0.15). In healthy animals, inhaled iloprost had only minimal haemodynamic effects and produced no direct effects on myocardial contractility, even after pharmacological blockade of the autonomic nervous system. CONCLUSIONS: In animals with acute pulmonary hypertension, inhaled iloprost improved global haemodynamics primarily via selective pulmonary vasodilatation and restoration of left ventricular preload. The reduction in right ventricular afterload is associated with a paradoxical decrease in right ventricular contractility. Our data suggest that this reflects an indirect mechanism by which ventriculo-vascular coupling is maintained at the lowest possible energetic cost. We found no evidence for a direct negative inotropic effect of iloprost.

Epoprostenol treatment of acute pulmonary hypertension is associated with a paradoxical decrease in right ventricular contractility.

OBJECTIVE: Prostacyclins have been suggested to exert positive inotropic effects which would render them particularly suitable for the treatment of right ventricular (RV) dysfunction due to acute pulmonary hypertension (PHT). Data on this subject are controversial, however, and vary with the experimental conditions. We studied the inotropic effects of epoprostenol at clinically recommended doses in an experimental model of acute PHT. DESIGN AND SETTING: Prospective laboratory investigation in a university hospital laboratory. SUBJECTS: Six pigs (36 +/- 7kg). INTERVENTIONS: Pigs were instrumented with biventricular conductance catheters, a pulmonary artery (PA) flow probe, and a high-fidelity pulmonary pressure catheter. Incremental doses of epoprostenol (10, 15, 20, 30, 40ng kg(-1) min(-1)) were administered in undiseased animals and after induction of acute hypoxia-induced PHT. MEASUREMENTS AND RESULTS: In acute PHT epoprostenol markedly reduced RV afterload (slopes of pressure-flow relationship in the PA from 7.0 +/- 0.6 to 4.2 +/- 0.7mmHg minl(-1)). This was associated with a paradoxical and dose-dependent decrease in RV contractility (slope of preload-recruitable stroke-work relationship from 3.0 +/- 0.4 to 1.6 +/- 0.2 mW s ml(-1); slope of endsystolic pressure-volume relationship from 1.5 +/- 0.3 to 0.7 +/- 0.3mmHg ml(-1)). Left ventricular contractility was reduced only at the highest dose. In undiseased animals epoprostenol did not affect vascular tone and produced a mild biventricular decrease in contractility. CONCLUSIONS: Epoprostenol has no positive inotropic effects in vivo. In contrast, epoprostenol-induced pulmonary vasodilation in animals with acute PHT was associated with a paradoxical decrease in RV contractility. This effect is probably caused indirectly by the close coupling of RV contractility to RV afterload. However, data from normal animals suggest that mechanisms unrelated to vasodilation are also involved in the observed negative inotropic response to epoprostenol.

Levosimendan improves right ventriculovascular coupling in a porcine model of right ventricular dysfunction.

OBJECTIVE: Experimental data suggest that levosimendan has pulmonary vasodilatory properties which, in combination with its positive inotropic effects, would render it particularly attractive for the treatment of right ventricular dysfunction. To test this hypothesis, we developed an experimental model of right ventricular failure and analyzed the effects of levosimendan on ventriculovascular coupling between the right ventricle and pulmonary artery (PA). DESIGN: Prospective, randomized, placebo-controlled animal study. SETTING: University hospital laboratory. SUBJECTS: Fourteen pigs (mean weight 36 +/- 1 kg). INTERVENTIONS: Pigs were instrumented with biventricular conductance catheters, a PA and right coronary artery flow probe, and a high-fidelity pulmonary pressure catheter. Right ventricular dysfunction was induced by repetitive episodes of ischemia/reperfusion in the presence of temporary PA constriction. Pigs were randomly assigned to receive levosimendan (120 mg/kg/hr [corrected] for 10 mins followed by continuous infusion of 60 mg/kg/hr [corrected] for 45 mins) or the placebo (control). MEASUREMENTS AND MAIN RESULTS: Induction of right ventricular dysfunction resulted in a 42% decrease in contractility (reduction in slope of preload recruitable stroke work [Mw] from 2.5 +/- 0.4 to 1.8 +/- 0.5 mW x sec x mL(-1); p = .02) and a 60% increase in right ventricular afterload (effective pulmonary arterial elastance [PA-Ea] from 0.6 +/- 0.1 to 1.0 +/- 0.3 mm Hg x mL(-1); p < .01). Right ventriculovascular coupling, as assessed by the quotient of right ventricular end-systolic elastance (E(max)) over PA-Ea, decreased from 1.23 +/- 0.38 to 0.64 +/- 0.21 (p = .03). Treatment with levosimendan improved right ventricular contractility (Mw from 1.9 +/- 0.4 to 2.9 +/- 0.5 mW x sec x mL(-1); p < .01), lowered right ventricular afterload (PA-Ea from 1.1 +/- 0.3 to 0.8 +/- 0.3 mm Hg x mL(-1); p = .02), and restored right ventriculovascular coupling to normal values (E(max)/PA-Ea = 1.54 +/- 0.51). Levosimendan also significantly increased coronary blood flow and left ventricular contractility (Mw from 7.2 +/- 3.3 to 9.5 +/- 2.9 mW x sec x mL(-1); p = .01) but did not affect biventricular diastolic function. CONCLUSIONS: In an experimental model of acute right ventricular dysfunction, levosimendan improved global hemodynamics and optimized right ventriculovascular coupling via a moderate increase in right ventricular contractility and a mild reduction of right ventricular afterload.

Thoracic epidural anesthesia impairs the hemodynamic response to acute pulmonary hypertension by deteriorating right ventricular-pulmonary arterial coupling.

OBJECTIVE: Thoracic epidural anesthesia is increasingly used in critically ill patients. This analgesic technique was shown to decrease left ventricular contractility, but effects on right ventricular function have not been reported. A deterioration of right ventricular performance may be clinically relevant for patients with acute pulmonary hypertension, in which right ventricular function is an important determinant of outcome. In the present study, we tested the hypothesis that thoracic epidural anesthesia decreases right ventricular contractility and limits its capacity to tolerate pulmonary hypertension. DESIGN: Prospective, placebo-controlled study using an established model of acute pulmonary hypertension. SETTING: University hospital laboratory. SUBJECTS: A total of 14 pigs (mean weight, 35 +/- 2 kg). INTERVENTIONS: After instrumentation with an epidural catheter, biventricular conductance catheters, a pulmonary flow probe, and a high-fidelity pulmonary pressure catheter, seven pigs received thoracic epidural anesthesia and seven pigs served as control. Hemodynamic measurements were performed in baseline conditions and after induction of pulmonary hypertension via hypoxic pulmonary vasoconstriction (Fio2 of 0.15). MEASUREMENTS AND MAIN RESULTS: Ventricular contractility was assessed using load- and heart rate-independent variables. Right ventricular afterload was characterized with instantaneous pressure-flow measurements. In baseline conditions, thoracic epidural anesthesia decreased left but not right ventricular contractility. In untreated animals, pulmonary hypertension was associated with an increase in right ventricular contractility and cardiac output. Pretreatment with thoracic epidural anesthesia completely abolished the positive inotropic response to acute pulmonary hypertension. As a result, ventriculo-vascular coupling between the right ventricle and pulmonary-arterial system deteriorated, and cardiac output was significantly lower in animals with thoracic epidural anesthesia than in untreated controls during hypoxia-induced pulmonary hypertension. CONCLUSIONS: Thoracic epidural anesthesia inhibits the native positive inotropic response of the right ventricle to increased afterload and deteriorates the hemodynamic effects of acute pulmonary hypertension.

Combined spinal-epidural anesthesia for cesarean delivery: dose-dependent effects of hyperbaric bupivacaine on maternal hemodynamics.

Hypotension remains an important side effect of spinal anesthesia for cesarean delivery. There is limited evidence that reducing the spinal dose has a favorable effect on maternal hemodynamic stability. We designed the present randomized trial to test the hypothesis that reducing the spinal dose of local anesthetics results in equally effective anesthesia and less maternal hypotension. Fifty term pregnant patients were randomly assigned to two study groups. In the HIGH-group combined spinal-epidural anesthesia was performed using 9.5 mg hyperbaric bupivacaine combined with 2.5 microg sufentanil. In the LOW-group combined spinal-epidural anesthesia was performed using 6.5 mg hyperbaric bupivacaine combined with 2.5 microg sufentanil. Demographic data, obstetrical data, visual analog scale score for pain, number of medical interventions for pain, maternal hemodynamics, and neonatal outcome were recorded. Patients in the HIGH-group experienced more pronounced and longer hypotensive periods as compared with the LOW-group. The mean lowest recorded systolic blood pressure was higher in the LOW-group (102 +/- 16 versus 88 +/- 16 in the HIGH-group; P < 0.05). More patients in the HIGH-group experienced hypotension compared with the LOW-group (68% versus 16%; P < 0.05). In the HIGH-group 15 patients required pharmacological treatment for hypotension compared with 5 in the LOW-group. Duration of effective anesthesia (block to cold sensation above or at T3) was longer in the HIGH-group as compared with the LOW-group (95 +/- 25 versus 68 +/- 18 min, respectively, P < 0.05). We conclude that small-dose spinal anesthesia (6.5 mg hyperbaric bupivacaine combined with sufentanil) better preserves maternal hemodynamic stability with equally effective anesthesia that is of shorter duration.

Longitudinal but not circumferential deformation reflects global contractile function in the right ventricle with open pericardium.

The clinical evaluation of right ventricular (RV) contractility is problematic because instantaneous RV volumetry is difficult to achieve. Our aim was to test whether global RV contractility can be assessed by using regional indexes in the longitudinal and/or circumferential axis. Six anesthetized adult ewes were instrumented with a RV conductance catheter and four RV free wall sonomicrometry crystals (interrogating the longitudinal and circumferential axes). Global and regional preload recruitable stroke work (PRSW) were measured by using acute vena cava occlusions at baseline, during esmolol and dobutamine infusion, and during stable low-preload and high-afterload conditions. The agreement between regional and global PRSW was assessed with regression and Bland-Altman analysis. Both regional PRSW indexes correlated well with global PRSW in baseline conditions, during inotropic modulation (R(2) = 0.83 and 0.74 for longitudinal and circumferential regional PRSW, respectively), and during preload reduction (R(2) = 0.62 and 0.83, respectively), but only longitudinal regional PRSW correlated with global PRSW in increased afterload conditions (R(2) = 0.59 and 0.13 for longitudinal and circumferential regional PRSW, respectively). We conclude that in the open-chest, open-pericardium animal model, deformation in the longitudinal axis accurately reflects global RV contractile function in baseline conditions and during acute load modulation, whereas circumferential motion is influenced by changes in afterload.

Remifentanil for fetal immobilization and maternal sedation during fetoscopic surgery: a randomized, double-blind comparison with diazepam.

Obstetric endoscopy procedures are routinely performed at our institution to treat selected complications of monochorionic twin gestation. We perform these procedures under combined spinal epidural anesthesia plus maternal sedation. In the absence of general anesthesia, fetal immobilization is not achieved. We hypothesized that remifentanil would induce adequate maternal sedation and provide fetal immobilization, which is equal or superior to that induced by diazepam. Fifty-four second trimester pregnant women were included in this randomized, double-blind trial. After combined spinal epidural anesthesia, maternal sedation was initiated using either incremental doses of diazepam or a continuous infusion of remifentanil. Maternal sedation, hemodynamics, side effects, and fetal hemodynamics and immobilization were evaluated before, during, and for 60 min after surgery. Remifentanil produced adequate maternal sedation with mild but clinically irrelevant respiratory depression (respiratory rate 13 +/- 4 breaths/min and Pco(2) 38.6 +/- 4 mm Hg at 40 min of surgery), whereas diazepam resulted in a more pronounced maternal sedation but no respiratory depression (respiratory rate 18 +/- 3 breaths/min and Pco(2) 32.7 +/- 3 mm Hg at 40 min of surgery). Compared with diazepam, fetal immobilization with remifentanil occurred faster and was more pronounced, resulting in improved surgical conditions; the number of gross body and limb movements was 12 +/- 4 (diazepam) versus 2 +/- 1 (remifentanil) at 40 min of surgery. Because of this, the mean (range) duration of surgery was significantly shorter in the remifentanil-treated patients, 60 (54-71) min versus 80 (60-90) min in the diazepam group. We conclude that remifentanil produces improved fetal immobilization with good maternal sedation and only minimal effects on maternal respiration.

Intrathecal clonidine prolongs labour analgesia but worsens fetal outcome: a pilot study.

PURPOSE: Intrathecal clonidine prolongs total duration of spinal bupivacaine analgesia. However, there are contradictory reports about its effect on maternal blood pressure and only limited data are available on fetal and neonatal outcome. In this study, we evaluated the efficacy of spinal clonidine combined with ropivacaine and sufentanil and its effects on maternal and fetal outcome. METHODS: Fifty patients requesting combined spinal epidural analgesia for labour pain relief were randomly assigned to receive intrathecal ropivacaine 3 mg, sufentanil 1.5 microg with or without clonidine 30 microg. Onset time and duration of analgesia, visual analogue scores for pain, blood pressure, ephedrine requirements, heart rate, incidence of nausea, pruritus and motor blockade, umbilical artery pH, fetal heart rate abnormalities and Apgar scores were noted and analyzed. RESULTS: Patients receiving spinal clonidine had significantly longer lasting analgesia compared to patients treated without clonidine (122 +/- 56 min vs 90 +/- 36 min, P < 0.05). Clonidine-treated patients experienced a more pronounced decrease in mean arterial pressure as compared to patients treated without clonidine (25 +/- 10% vs 15 +/- 12%, P < 0.05). The groups also differed in ephedrine requirement (4.91 mg vs 0.75 mg, P < 0.05), number of new onset fetal heart rate abnormalities (28% vs 0%, P < 0.05) and umbilical artery pH (7.219 +/- 0.096 vs 7.289 +/- 0.085, P < 0.05). CONCLUSION: Intrathecal clonidine prolongs spinal analgesia with ropivacaine and sufentanil at the expense of maternal hypotension, worse fetal well being and worse neonatal umbilical artery pH. We do not recommend routine administration of spinal clonidine 30 microg to sufentanil and ropivacaine for labour pain relief.

Morbidity and mortality related to anaesthesia outside the operating room.

PURPOSE OF REVIEW: The purpose of this review is to provide information related to morbidity and mortality associated with anaesthesia outside the operating room. RECENT FINDINGS: There is an increasing demand for anaesthesia at remote locations. Because of its specific characteristics, resulting from the location and the patient, morbidity and mortality rates of remote location anaesthesia could differ from conventional operating room anaesthesia. However, no studies are currently available. On the basis of morbidity and mortality data from conventional operating room anaesthesia, we reached some important conclusions with regard to the safety of anaesthesia outside the operating room. A well-equipped anaesthesia machine, standard monitoring (electrocardiogram, oxygen saturation and non-invasive blood pressure), trained personnel and adequate planning should be standard for all out of the operating room procedures. When all these are in place, the incidence of morbidity or mortality should be comparable to that of anaesthesia provided in the operating room. SUMMARY: There is certainly a need for studies concerning morbidity and mortality at remote location anaesthesia. Special care for the prevention of hypothermia should be given to those patients undergoing long-lasting diagnostic procedures, e.g. magnetic resonance imaging scans or cardiological investigations.