Management of Challenging Cardiopulmonary Bypass Separation.

SEPARATION from cardiopulmonary bypass (CPB) after cardiac surgery is a progressive transition from full mechanical circulatory and respiratory support to spontaneous mechanical activity of the lungs and heart. During the separation phase, measurements of cardiac performance with transesophageal echocardiography (TEE) provide the rationale behind the diagnostic and therapeutic decision-making process. In many cases, it is possible to predict a complex separation from CPB, such as when there is known preoperative left or right ventricular dysfunction, bleeding, hypovolemia, vasoplegia, pulmonary hypertension, or owing to technical complications related to the surgery. Prompt diagnosis and therapeutic decisions regarding mechanical or pharmacologic support have to be made within a few minutes. In fact, a complex separation from CPB if not adequately treated leads to a poor outcome in the vast majority of cases. Unfortunately, no specific criteria defining complex separation from CPB and no management guidelines for these patients currently exist. Taking into account the above considerations, the aim of the present review is to describe the most common scenarios associated with a complex CPB separation and to suggest strategies, pharmacologic agents, and para-corporeal mechanical devices that can be adopted to manage patients with complex separation from CPB. The routine management strategies of complex CPB separation of 17 large cardiac centers from 14 countries in 5 continents will also be described.

Correction to: Protective ventilation with high versus low positive end-expiratory pressure during one-lung ventilation for thoracic surgery (PROTHOR): study protocol for a randomized controlled trial.

After publication of the original article [1], the authors have notified us that two of the collaborator first and last names have been inverted in the "PROTHOR Investigators" table.

Protective ventilation with high versus low positive end-expiratory pressure during one-lung ventilation for thoracic surgery (PROTHOR): study protocol for a randomized controlled trial.

BACKGROUND: Postoperative pulmonary complications (PPC) may result in longer duration of in-hospital stay and even mortality. Both thoracic surgery and intraoperative mechanical ventilation settings add considerably to the risk of PPC. It is unclear if one-lung ventilation (OLV) for thoracic surgery with a strategy of intraoperative high positive end-expiratory pressure (PEEP) and recruitment maneuvers (RM) reduces PPC, compared to low PEEP without RM. METHODS: PROTHOR is an international, multicenter, randomized, controlled, assessor-blinded, two-arm trial initiated by investigators of the PROtective VEntilation NETwork. In total, 2378 patients will be randomly assigned to one of two different intraoperative mechanical ventilation strategies. Investigators screen patients aged 18 years or older, scheduled for open thoracic or video-assisted thoracoscopic surgery under general anesthesia requiring OLV, with a maximal body mass index of 35 kg/m2, and a planned duration of surgery of more than 60 min. Further, the expected duration of OLV shall be longer than two-lung ventilation, and lung separation is planned with a double lumen tube. Patients will be randomly assigned to PEEP of 10 cmH2O with lung RM, or PEEP of 5 cmH2O without RM. During two-lung ventilation tidal volume is set at 7 mL/kg predicted body weight and, during OLV, it will be decreased to 5 mL/kg. The occurrence of PPC will be recorded as a collapsed composite of single adverse pulmonary events and represents the primary endpoint. DISCUSSION: PROTHOR is the first randomized controlled trial in patients undergoing thoracic surgery with OLV that is adequately powered to compare the effects of intraoperative high PEEP with RM versus low PEEP without RM on PPC. The results of the PROTHOR trial will support anesthesiologists in their decision to set intraoperative PEEP during protective ventilation for OLV in thoracic surgery. TRIAL REGISTRATION: The trial was registered in clinicaltrials.gov ( NCT02963025 ) on 15 November 2016.

Videolaryngoscopes for placement of double lumen tubes: Is it time to say goodbye to direct view?

The advances in thoracic procedures require optimum lung separation to provide adequate room for surgical access. This can be achieved using either a double-lumen tube (DLT) or a bronchial blocker (BB). Most thoracic anesthesiologists prefer the use of DLT. However, lung separation in patients with potential difficult airway can be achieved using either BB through a single lumen tube or placement of a DLT over a tube exchanger or a fiberoptic bronchoscope. Numerous videolaryngoscopes (VL) have been introduced offering both optical and video options to visualize the glottis. Many studies reported improved glottis visualization and easier DLT intubation in patients with normal and potential difficult airway. However, these studies have a wide diversity of outcomes, which may be attributed to the differences in their designs and the prior experience of the operators in using the different devices. In the present review, we present the main outcomes of the available publications, which have addressed the use of VL-guided DLT intubation. Currently, there is enough evidence supporting using VL for DLT intubation in patients with predicted and unanticipated difficult airway. In conclusion, the use of VL could offer an effective method of DLT placement for lung separation in patients with the potential difficult airway.

Effect of preoperative pregabalin on post-caesarean delivery analgesia: a dose-response study.

INTRODUCTION: We hypothesised that preoperative administration of a single-dose of pregabalin would be associated with lower morphine consumption after uncomplicated caesarean delivery. METHODS: After Institutional Ethics Committee approval, 135 parturients scheduled for elective caesarean delivery under spinal anaesthesia were randomly allocated to receive either placebo, or oral pregabalin 150mg or 300mg, one hour before induction of anaesthesia. Maternal cumulative morphine requirement at 24h, pain scores, sedation scores, nausea and vomiting, pruritus, pregabalin-related adverse effects, Apgar scores, Neurologic and Adaptive Capacity scores and umbilical cord acid-base status were recorded. RESULTS: Compared with placebo or pregabalin 150mg, the use of a preoperative dose of pregabalin 300mg resulted in significantly lower cumulative morphine consumption at 24h (mean dose: placebo 12.9mg [95% CI 11.6 to 14.2]; pregabalin 150mg 11.9mg; [95% CI 10.7 to 13.1]; pregabalin 300mg 6mg [95% CI 5.4 to 7.3]; P<0.001). Pregabalin 300mg resulted in lower pain scores at 4h and 6h after delivery (P<0.001), and fewer instances of nausea, vomiting and pruritus (P<0.009). Dizziness and abnormal vision were observed most frequently in the pregabalin 300mg group (P<0.05 and P<0.009, respectively). The three groups were similar in terms of maternal sedation, Apgar scores, Neurologic and Adaptive Capacity scores and umbilical cord acid-base status. Three babies in the pregabalin 300mg group (6.7%) experienced short-term poor latching-on for breastfeeding. CONCLUSION: In our study, preoperative administration of pregabalin 300mg reduced postoperative morphine consumption and early postoperative pain in parturients undergoing elective caesarean delivery, although maternal side effects were more common.

Efficacy of dexmedetomidine in suppressing cardiovascular and hormonal responses to general anaesthesia for caesarean delivery: a dose-response study.

BACKGROUND: Preoperative dexmedetomidine administration blunts haemodynamic and hormonal responses to tracheal intubation and reduces anaesthetic requirements. We hypothesized that dexmedetomidine would reduce the maternal haemodynamic and hormonal responses to elective caesarean delivery without harmful neonatal effects. METHODS: After ethical approval, 68 parturients scheduled for elective caesarean delivery under general anaesthesia were randomly allocated to receive either placebo, or 0.2, 0.4 or 0.6 µg/kg/h intravenous dexmedetomidine (n=17 per group) 20 min before induction. Anaesthesia was induced using a rapid-sequence technique with propofol and suxamethonium, and was maintained with 0.5-0.75 minimum alveolar concentration sevoflurane. Changes in maternal heart rate, mean blood pressure, minimum alveolar concentration sevoflurane, uterine tone, serum cortisol level, and Apgar scores, Neurologic Adaptive Capacity Scores and acid-base status were recorded. RESULTS: After induction, patients receiving dexmedetomidine had smaller increases in heart rate (P<0.001) than those in the placebo group. Patients who received 0.4 and 0.6 µg/kg/h infusions of dexmedetomidine showed slower heart rates (-21.5% and -36%, respectively; P<0.001), lower mean blood pressures (-17% and -25%, respectively; P<0.001), sevoflurane minimum alveolar concentrations (-40% and -44.5%, respectively; P<0.001) and serum cortisol levels (-27% and -34.6%, respectively; P<0.001) and higher sedation scores for the first 15 min after extubation and greater uterine tone (P<0.002). Apgar scores, NACS and acid-base status were similar in the four groups. CONCLUSION: Preoperative administration of dexmedetomidine 0.4 and 0.6 µg/kg/h is effective in attenuating the maternal haemodynamic and hormonal responses to caesarean delivery under sevoflurane anaesthesia without adverse neonatal effects.

A randomized study of the effects of preoperative ketorolac on general anaesthesia for caesarean section.

BACKGROUND: Ketorolac may attenuate the maternal stress response to tracheal intubation, while avoiding opioid-induced neonatal depression. We aimed to evaluate the haemodynamic and hormonal effects of prophylactic ketorolac on surgical stress and analgesia after caesarean delivery. METHODS: After ethical approval, 90 patients scheduled for elective caesarean delivery were randomly allocated receive either ketorolac 15 mg i.v. bolus 20 min before induction, followed by an infusion of 7.5 mg/h (n=45), or saline placebo (n=45). Anaesthesia was maintained with 50% nitrous oxide in oxygen with 0.5% isoflurane. Haemodynamic variables, plasma cortisol concentrations, uterine relaxation, need for supplementary doses of oxytocin, peri-operative blood loss, haematocrit, Apgar scores at 1 and 5 min, postoperative pain scores at rest and movement, and tramadol consumption were recorded. RESULTS: After induction, patients receiving ketorolac had a smaller increase in heart rate, systolic and mean arterial blood pressure (P<0.001) and lower plasma cortisol concentrations, (32.2+/-7.61 vs. 45+/-15.1 microg/dL, P<0.05), lower pain scores at rest and movement for the first two postoperative hours (P<0.001) and a longer time to first request for analgesia. Fewer patients in the ketorolac group received tramadol in the four hours after surgery (7 (15.6%) vs. 14 (31.1%), P=0.004). There were no differences between groups in peri-operative blood loss, vomiting or Apgar scores. There was no echocardiographic evidence of premature closure of the ductus arteriosus in the newborns. CONCLUSION: Prophylactic ketorolac is safe and effective in attenuating the maternal stress response to intubation and improves the quality of analgesia after caesarean delivery.