Management of rocuronium neuromuscular block using a protocol for qualitative monitoring and reversal with neostigmine.

BACKGROUND: Neuromuscular block using subjective monitoring and neostigmine reversal is commonly associated with postoperative residual neuromuscular block. We tested whether a protocol for the management of neuromuscular block that specified appropriate dosing and optimal neostigmine reversal was associated with a reduction in postoperative residual neuromuscular block. METHODS: Rocuronium administration was guided by surgical requirements and based on the ideal body weight, with dose reductions for female sex and age >55 yr. Neostigmine was administered in adjusted doses after a train-of-four count of four was confirmed at the thumb. The protocol ensured a minimum of 10 min between neostigmine administration and tracheal extubation. We measured the postoperative residual neuromuscular block in patients undergoing abdominal surgery before and after introduction of the protocol. Pre-specified primary and secondary endpoints were incidence of postoperative residual neuromuscular block and severe postoperative residual neuromuscular block at the time of tracheal extubation, defined as normalised train-of-four ratios <0.9 and <0.7, respectively. RESULTS: The incidence of postoperative residual neuromuscular block at tracheal extubation was 14/40 (35%) for patients managed according to the protocol compared with 22/38 (58%) for patients in the control group, odds ratio of 0.39, and 95% confidence interval of 0.14-1.07; P=0.068. The incidence of severe postoperative residual neuromuscular block at tracheal extubation showed a highly significant difference, odds ratio=0.06, and confidence interval of 0.00-0.43; P=0.001. CONCLUSIONS: The incidence of severe postoperative residual neuromuscular block was significantly reduced after the protocol was introduced. Given the limitations inherent in this before-and-after study, further research is needed to confirm these results. CLINICAL TRIAL REGISTRATION: NCT02660398.

The use of acute normovolemic hemodilution in paediatric cardiac surgery.

BACKGROUND: Acute normovolemic hemodilution (ANH) is considered safe and effective in decreasing perioperative transfusion in paediatric populations undergoing high blood-loss surgeries. We determined the association between ANH and the intraoperative use of allogeneic blood products in paediatric cardiac surgery patients. METHODS: This is a single-centre retrospective cohort study including paediatric patients between 0 and 36 months of age undergoing surgical repair or palliation of their cardiac defect with the use of cardiopulmonary bypass between November 2013 and November 2014. Our primary endpoint was the volume per kilogram of body weight of any blood product administered. Secondary endpoints were postoperative bleeding, coagulation profile, creatinine, vasoactive support, duration of mechanical ventilation, and hospital stay. RESULTS: In all, 50 patients met eligibility criteria and were included. Of those, seven were exposed to ANH and while 43 patients were treated according to usual care. Baseline characteristics were similar in both groups. After adjustment for baseline characteristics including age, American Society of Anaesthesiologists (ASA) classification, and Risk Adjusted Congenital Heart Surgery score, ANH was associated with reduced administration of allogenic blood products, with the mean difference between groups of 57.5 ml/kg (95% CI: 34.8, 80.2). The ANH group had lower blood losses at 6 and 24 h postoperatively. There were no differences in the duration of ICU or hospital stay. CONCLUSION: We found a reduction in the administration of blood products and lower postoperative blood losses associated with the use of ANH in paediatric cardiac surgery patients. The data suggest that ANH might be beneficial in reducing perioperative morbidity in this patient population.

Characteristics of sepsis-induced cardiac dysfunction using speckle-tracking echocardiography: a feasibility study.

Septic cardiomyopathy is commonly encountered in patients with severe sepsis and septic shock. This study explores whether novel global and segmental echocardiographic markers of myocardial deformation, using two-dimensional speckle tracking, are associated with adverse sepsis outcomes. We conducted a retrospective observational feasibility study, at a tertiary care centre, of patients admitted to the ICU with a diagnosis of sepsis who underwent an echocardiogram within the first week of sepsis diagnosis. Data were collected on chamber dimensions, systolic and diastolic function, demographics, haemodynamics, and laboratory parameters. Global and segmental left ventricular longitudinal strain (LVLS) and tissue mitral annular displacement (TMAD) were assessed on 12 left ventricular segments and six mitral annulus segments in apical views, respectively. We explored associations of abnormal LVLS and TMAD with duration of mechanical ventilation, hospital length of stay, and mortality. Fifty-four patients were included. Global LVLS was not associated with any of the primary study endpoints. However, reduced systolic LVLS of the basal anterior segment was associated with in-hospital mortality. There was a suggestion that patients with a reduced global TMAD were associated with an increased risk of mortality and a short length of hospital stay but these associations were not statistically significant. Reduced global LVLS was associated with lower ejection fraction. Reduced global TMAD was associated with reduced global and segmental LVLS, reduced left ventricular ejection fraction, and increased left ventricular end-systolic and end-diastolic volumes. Speckle-tracking echocardiography can be performed feasibly in patients in sepsis. Global and segmental left ventricular deformation indices are associated with ejection fraction. Further studies need to evaluate the ability of these new indices to predict sepsis outcomes.

Patient-level interventions to prevent the acquisition of resistant gram-negative bacteria in critically ill patients: a systematic review.

The rising incidence of multidrug-resistant Gram-negative bacterial (MDR-GNB) infections acquired in intensive care units has prompted a variety of patient-level infection control efforts. However, it is not known whether these measures are effective in reducing colonisation and infection. The purpose of this systematic review was to assess the efficacy of patient-level interventions for the prevention of colonisation with MDR-GNB and whether these interventions are associated with a reduction in the rate of infection due to MDR-GNB in the intensive care unit. Searches were conducted on PubMed, Cochrane, EMBASE and World of Science databases to identify comparative interventional studies on patient-level interventions implemented in the intensive care unit. Literature published in English, Spanish or French from January 1, 2000, until April 30, 2013, was searched. A total of 631 reports were found and we included and analysed 13 comparative studies that reported outcomes for an intervention compared with a control group. There were ten randomised and three observational interventional trials evaluating seven interventions. Overall, there was a reduction in colonisation (odds ratio [OR] 0.75; 95% confidence interval [CI] 0.66 to 0.85) and infection (OR 0.66; 95% CI 0.59 to 0.75) with MDR-GNB. This trend persisted after restricting pooled analysis to randomised controlled trials (pooled OR 0.66; 95% CI 0.57 to 0.76 and pooled OR 0.62; 95% CI 0.54 to 0.72, respectively). We identified a significant reduction in MDR-GNB colonisation and infection through the use of patient-level interventions. This effect was mostly accounted for by selective digestive decontamination. However, given the limitations of the analysed trials, adequately powered controlled studies are needed to further explore the effects of patient-level interventions on colonisation and infection with MDR-GNB.

Sedation practices in a cohort of critically ill patients receiving prolonged mechanical ventilation.

BACKGROUND: The aim of this paper was to describe type and amount of sedatives, opioid analgesics and anti- psychotics administered to critically ill patients receiving prolonged mechanical ventilation and identify patient-specific factors associated with their administration. METHODS: Retrospective cohort study of adult patients mechanically ventilated for ≥14 days over a two-year period. RESULTS: The majority of patients (88%) received lorazepam for sedation (median 14-day dose 168 mg, IQR 25-606). Morphine (median 14-day dose 125 mg, IQR 0-850) and fentanyl (median 14-day dose 2032 mcg, IQR 175-15346) were administered with relative equal frequency. Only 48% of the cohort received anti-psychotics during the first 14 days. Age was inversely associated with cumulative dose of lorazepam equivalents (ratio 0.97; 95% CI 0.95-0.99), propofol (ratio 0.93; 95% CI 0.89-0.96), and morphine equivalents (ratio 0.97; 95% CI 0.96-0.98). Substance abuse was associated with cumulative dose of lorazepam (ratio 3.37; 95% CI 1.14-8.21) and morphine equivalents (ratio 3.09; 95% CI 1.48-6.44). Ethanol abuse was associated with >50% lower cumulative dose of morphine equivalents (ratio 0.47; 95% CI 0.25-0.87). CONCLUSION: In critically ill patients receiving prolonged ventilation, history of substance abuse predicted a 3-fold increase in 14-day cumulative dose of sedatives and opioids used. Conversely, older age was associated with decreased use of sedatives and opioids and history of alcohol abuse was only associated with decreased opioid use. Overall, patients receiving prolonged mechanical ventilation appeared to consume high cumulative doses of sedatives and opioids, with less frequent use of antipsychotics. Accounting for patient characteristics may help identify individuals with varying sedative needs.

Cardioplegia and ventricular late potentials in cardiac surgical patients.

BACKGROUND AND OBJECTIVE: Ventricular late potentials (LP) recording with signal-averaged electrocar- diogram allow identifying patients at risk of sudden death and ventricular tachycardia. Cardiac surgery with cardiopulmonary bypass (CPB) could predispose to the development of myocardial ischemia related to imperfect cardioplegia. To the best of our knowledge, no study investigated the protection of cardioplegia and CPB regarding the occurrence of LP in patients without previous myocardial infarction and undergoing cardiac surgery. METHODS: In 61 elective patients scheduled for cardiac surgery involving CPB, signal-averaged electrocar- diogram was performed the day before and 24-48 h after the surgery. The electrodes were positioned according to Frank's orthogonal derivations. Twenty five patients were excluded because of poor quality signals, leaving 36 patients (age, 64 ± 14) available for the analyses. An abnormal signal-averaged electrocardiogram was considered when ≥2 of the recorded indexes were present. McNemar's tests were performed on the dichotomized values to investigate differences in pre-post scores. RESULTS: The mean CPB duration was of 110 ± 57 min. Patients scheduled for cardiac surgery do not exhibited LP after CPB (no significant difference in pre-post CPB scores, P = NS). The probability of a patient with a negative score transitioning to a positive score was 0.23 (P = NS). CONCLUSIONS: The present study in cardiac surgical patients suggests that cardioplegia associated to CPB has no significant impact on the occurrence of LP, irrespective of surgery performed.

The second-generation air-Q intubating laryngeal mask for airway maintenance during anaesthesia in adults: a report of the first 70 uses.

The second-generation air-Q intubating laryngeal airway is a newer commercially available supraglottic airway device. In this retrospective review, we describe our initial clinical experience of 70 insertions. The ease and number of insertion attempts, airway leak pressure, device positioning, duration of use, success of fibreoptic-aided intubation and oropharyngeal morbidity were recorded. The intubating laryngeal airway was successfully inserted in all 770 patients and functioned adequately as a primary airway in all 57 patients in which it was used. The median airway leak pressure was 25 and 30 cmH2O for the single-use and reusable devices (P = 0.001), respectively. Fibreoptic-aided intubation using the intubating laryngeal airway as a conduit was successful in 12/13 (92%) cases. One in four (26%) patients complained of mild sore throat postoperatively before discharge. In our series, the intubating laryngeal airway performed adequately as a primary airway during anaesthesia with respect to ease of insertion, adequacy of airway maintenance, and as a conduit for intubation in both anticipated and unanticipated difficult airways. Further investigation is warranted regarding the role of the intubating laryngeal airway as a conduit for both blind and fibreoptic-aided intubation. In addition, the incidence of postoperative throat complaints deserves further scrutiny.

Tezosentan normalizes hepatomesenteric perfusion in a porcine model of cardiac tamponade.

BACKGROUND: To investigate endothelin-1 (ET-1)-dependent hepatic and mesenteric vasoconstriction, and oxygen and lactate fluxes in an acute, fixed low cardiac output (CO) state. METHODS: Sixteen anesthetized, mechanically ventilated pigs were studied. Cardiac tamponade was established to reduce portal venous blood flow (Q(PV)) to 2/3 of the baseline value. CO, hepatic artery blood flow (Q(HA)), Q(PV), hepatic laser-Doppler flow (LDF), hepatic venous and portal pressure, and hepatic and mesenteric oxygen and lactate fluxes were measured. Hepatic arterial (R(HA)), portal (R(HP)) and mesenteric (R(mes)) vascular resistances were calculated. The combined ET(A)-ET(B) receptor antagonist tezosentan (RO 61-0612) or normal saline vehicle was infused in the low CO state. Measurements were made at baseline, after 30, 60, 90 min of tamponade, and 30, 60, 90 min following the infusion of tesozentan at 1 mg/kg/h. RESULTS: Tamponade decreased CO, Q(PV), Q(HA), LDF, hepatic and mesenteric oxygen delivery, while hepatic and mesenteric oxygen extraction and lactate release increased. R(HA), R(HP) and R(mes) all increased. Ninety minutes after tesozentan, Q(PV), LDF and hepatic and mesenteric oxygen delivery and extraction increased approaching baseline values, but no effect was seen on CO or Q(HA). Hepatic and mesenteric handling of lactate converted to extraction. R(HA), R(HP) and R(mes) returned to baseline values. No changes were observed in these variables among control animals not receiving tesozentan. CONCLUSION: In a porcine model of acute splanchnic hypoperfusion, unselective ET-1 blockade restored hepatomesenteric perfusion and reversed lactate metabolism. These observations might be relevant when considering liver protection in low CO states.

In vitro evaluation of the effectiveness of distal protection in the prevention of cerebral thromboembolism during carotid stent placement.

RATIONALE AND OBJECTIVES: The purpose of this in vitro study was to evaluate and quantify the benefit of the balloon protection device, to identify the most effective sequence of irrigation or flushing, and to determine the most effective catheter position to remove the maximum number of emboli or debris beneath the flow-arrest balloon. MATERIALS AND METHODS: Silicone models of the neurovasculature were attached to a systodiastolic pump. Stents were placed in carotid stenoses by using the distal flow protection technique. Embolic material was released within the stent. The effectiveness of different irrigation techniques was evaluated. RESULTS: Aspiration under the balloon through the guiding catheter with a 60-mL syringe followed by one power injection at 40 mL injected at 2 mL/sec will result in removal of about 98% of potential emboli from the internal carotid artery [corrected]. CONCLUSION: In vitro evaluation of the distal flow protection technique indicates that it should reduce stroke risk during carotid stent placement.