Non-ventilated lung deflation during one-lung ventilation with a double-lumen endotracheal tube: a randomized-controlled trial of occluding the non-ventilated endobronchial lumen before pleural opening.

PURPOSE: Lung deflation during one-lung ventilation (OLV) is thought to be faster using a double-lumen endotracheal tube (DL-ETT) than with a bronchial blocker, especially when the non-ventilated lumen is opened to allow egress of air from the operative lung. Nevertheless, ambient air can also be entrained into the non-ventilated lumen before pleural opening and subsequently delay deflation. We therefore hypothesized that occluding the non-ventilated DL-ETT lumen during OLV before pleural opening would prevent air entrainment and consequently enhance operative lung deflation during video-assisted thoracoscopic surgery (VATS). METHODS: Thirty patients undergoing VATS using DL-ETT to allow OLV were randomized to having the lumen of the operative lung either open (control group) or occluded (intervention group) to ambient air. The primary outcome was the time to lung collapse evaluated intraoperatively by the surgeons. The T50, an index of rate of deflation, was also determined from a probabilistic model derived from intraoperative video clips presented in random order to three observers. RESULTS: The median [interquartile range] time to lung deflation occurred faster in the intervention group than in the control group (24 [20-37] min vs 54 [48-68] min, respectively; median difference, 30 min; 95% confidence interval [CI], 14 to 46; P < 0.001). The estimated T50 was 32.6 min in the intervention group compared with 62.3 min in the control group (difference, - 29.7 min; 95% CI, - 51.1 to - 8.4; P = 0.008). CONCLUSION: Operative lung deflation during OLV with a DL-ETT is faster when the operative lumen remains closed before pleural opening thus preventing it from entraining ambient air during the closed chest phase of OLV. TRIAL REGISTRATION: www.clinicaltrials.gov (NCT03508050); registered 27 September 2017.

RéSUMé: OBJECTIF: On pense que la déflation pulmonaire pendant la ventilation unipulmonaire (VUP) est plus rapide à l'aide d'un tube endotrachéal à double lumière (TET-DL) qu'avec un bloqueur bronchique, surtout lorsque la lumière non ventilée est ouverte pour permettre l'évacuation de l'air du poumon opéré. Néanmoins, l'air ambiant peut également être entraîné dans la lumière non ventilée avant l'ouverture pleurale et ainsi retarder la déflation. Nous avons donc émis l'hypothèse que l'occlusion de la lumière non ventilée du TET-DL pendant la VUP avant l'ouverture de la plèvre empêcherait l'entraînement d'air et accélérerait par conséquent la déflation du poumon opéré pendant une chirurgie thoracoscopique vidéo-assistée (VATS). MéTHODE: Trente patients subissant une VATS avec un TET-DL pour permettre une VUP ont été randomisés à une ouverture (groupe témoin) ou à une occlusion (groupe intervention) de la lumière du poumon opéré à l'air ambiant. Le critère d'évaluation principal était le temps jusqu'au collapsus du poumon tel qu'évalué pendant l'opération par les chirurgiens. Le T50, un indice du taux de déflation, a également été déterminé à partir d'un modèle probabiliste dérivé de clips vidéo peropératoires présentés de façon randomisée à trois observateurs. RéSULTATS: Le temps médian [écart interquartile] jusqu'à la déflation du poumon était plus court dans le groupe d'intervention que dans le groupe témoin (24 [20-37] min vs 54 [48-68] min, respectivement; différence médiane, 30 min; intervalle de confiance [IC] à 95 %, 14 à 46; P < 0,001). Le T50 estimé était de 32,6 min dans le groupe d'intervention comparativement à 62,3 min dans le groupe témoin (différence, -29,7 min; IC 95 %, -51,1 à -8,4; P = 0,008). CONCLUSION: La déflation du poumon opéré pendant une VUP avec un TET-DL est plus rapide quand la lumière opératoire reste fermée avant l'ouverture pleurale, l'empêchant ainsi d'entraîner l'air ambiant pendant la phase pré ouverture pleurale de la VUP. ENREGISTREMENT DE L'éTUDE: www.clinicaltrials.gov (NCT03508050); enregistrée le 27 septembre 2017.

Double-lumen endotracheal tubes and bronchial blockers exhibit similar lung collapse physiology during lung isolation.

PURPOSE: Double-lumen endotracheal tubes (DL-ETT) and bronchial blockers (BB) are frequently used to allow one-lung ventilation (OLV) during video-assisted thoracic surgery (VATS). Recently, faster lung collapse has been documented with a BB than with a DL-ETT. The physiologic mechanisms behind this faster collapse remained unknown. We aimed to measure ambient air absorption (Vresorb) and intra-bronchial pressure (Pairway) into the non-ventilated lung during OLV using DL-ETT and BB. METHODS: Patients undergoing VATS and OLV for lung resection were randomly assigned to have measurements made of Vresorb or Pairway within the non-ventilated lung using either a DL-ETT or BB. RESULTS: Thirty-nine patients were included in the analyses. The mean (standard error of the mean [SEM]) Vresorb was similar in the DL-ETT and BB groups [504 (85) vs 630 (86) mL, respectively; mean difference, 126; 95% confidence interval [CI], -128 to 380; P = 0.31]. The mean (SEM) Pairway became progressively negative in the non-ventilated lung in both the DL-ETT and the BB groups reaching [-20 (5) and -31 (10) cmH2O, respectively; mean difference, -11; 95% CI, -34 to 12; P = 0.44] at the time of the pleural opening. CONCLUSIONS: During OLV before pleural opening, entrainment of ambient air into the non-ventilated lung occurs when the lumen of the lung isolation device is kept open. This phenomenon is prevented by occluding the lumen of the isolation device before pleural opening, resulting in a progressive build-up of negative pressure in the non-ventilated lung. Future clinical studies are needed to confirm these physiologic results and their impact on lung collapse and operative outcomes. TRIAL REGISTRATION: www.clinicaltrials.gov (NCT02919267); registered 28 September 2016.

RéSUMé: OBJECTIF: Les tubes endotrachéaux à double lumière (TET-DL) et les bloqueurs bronchiques (BB) sont fréquemment utilisés pour l'isolation pulmonaire pendant une chirurgie thoracique assistée par vidéoscopie. Récemment, un affaissement pulmonaire plus rapide avec un BB qu'avec un TET-DL a été documenté. Les mécanismes physiologiques derrière cet affaissement plus rapide demeurent inconnus. Notre objectif était de mesurer l'absorption de l'air ambiant (Vresorb) et la pression intra-bronchique (Paérienne) dans le poumon non ventilé pendant la ventilation à un poumon en utilisant un TET-DL et un BB. MéTHODE: Les patients subissant une chirurgie thoracique assistée par vidéoscopie et recevant une ventilation unipulmonaire à l'aide d'un TET-DL ou d'un BB pour une résection pulmonaire ont été aléatoirement assignés à des mesures de Vresorb ou Paérienne dans le poumon non ventilé. RéSULTATS: Trente-neuf patients ont été inclus dans les analyses. La Vresorb moyenne (erreur-type sur la moyenne) était similaire dans les groupes TET-DL et BB [504 (85) vs 630 (86) mL, respectivement; différence moyenne, 126; intervalle de confiance [IC] 95 %, -128 à 380; P = 0,31]. La Paérienne moyenne (erreur-type sur la moyenne) est devenue progressivement négative dans le poumon non ventilé dans les groupes TET-DL et BB en atteignant [-20 (5) et -31 (10) cmH2O, respectivement; différence moyenne, -11; IC 95 %, -34 à 12; P = 0,44] au moment de l'ouverture de la plèvre. CONCLUSION: Pendant la ventilation unipulmonaire avant l'incision de la plèvre, un appel d'air ambiant dans le poumon non ventilé se produit quand la portion du dispositif d'isolation pulmonaire est maintenue ouverte. Ce phénomène peut être évité en occluant la lumière du dispositif d'isolation pulmonaire avant l'ouverture de la plèvre, ce qui entraînera une accumulation progressive de pression négative dans le poumon non ventilé. De futures études cliniques sont nécessaires pour confirmer ces résultats physiologiques et leur impact sur l'affaissement pulmonaire et les devenirs opératoires. ENREGISTREMENT DE L'éTUDE: www.clinicaltrials.gov (NCT02919267); enregistrée le 28 septembre 2016.

Bronchial blocker versus left double-lumen endotracheal tube in video-assisted thoracoscopic surgery: a randomized-controlled trial examining time and quality of lung deflation.

INTRODUCTION: Double-lumen endotracheal tubes (DL-ETT) and bronchial blockers (BB) have both been used for lung isolation in video-assisted thoracic surgery (VATS). Though not well studied, it is widely thought that a DL-ETT provides faster and better quality lung collapse. The aim of this study was to compare a BB technique vs a left-sided DL-ETT strategy with regard to the time and quality of lung collapse during one-lung ventilation (OLV) for elective VATS. METHODS: Forty patients requiring OLV for VATS were randomized to receive a BB (n = 20) or a left-sided DL-ETT (n = 20). The primary endpoint was the time from pleural opening (performed by the surgeon) until complete lung collapse. The time was evaluated offline by reviewing video recorded during the VATS. The quality of lung deflation was also graded offline using a visual scale (1 = no lung collapse; 2 = partial lung collapse; and 3 = total lung collapse) and was recorded at several time points after pleural incision. The surgeon also graded the time to complete lung collapse and quality of lung deflation during the procedure. The surgeon's guess as to which device was used for lung isolation was also recorded. RESULTS: Of the 40 patients enrolled in the study, 20 patients in the DL-ETT group and 18 in the BB group were analyzed. There mean (standard deviation) time to complete lung collapse of the operative lung was significantly faster using the BB compared with using the DL-ETT [7.5 (3.8) min vs 36.6 (29.1) min, respectively; mean difference, 29.1 min; 95% confidence interval, 1.8 to 7.2; P < 0.001]. Overall, a higher proportion of patients in the BB group than in the DL-ETT group achieved a quality of lung collapse score of 3 at five minutes (57% vs 6%, respectively; P < 0.004), ten minutes (73% vs 14%, respectively; P = 0.005), and 20 min (100% vs 25%, respectively; P = 0.002) after opening the pleura. The surgeon incorrectly guessed the type of device used in 78% of the BB group and 50% of the DL-ETT group (P = 0.10). CONCLUSION: The time and quality of lung collapse during OLV for VATS was significantly better when using a BB than when using a left-sided DL-ETT. Surgeons could not reliably determine which device was being used based on the time and quality of lung collapse. This trial was registered at ClinicalTrials.gov number, NCT01615263.

Effect of thoracic epidural analgesia on clinical outcomes following transapical transcatheter aortic valve implantation.

OBJECTIVE: To determine the impact of perioperative thoracic epidural analgesia (TEA) on acute and late outcomes following transapical transcatheter aortic valve implantation (TA-TAVI). PATIENTS AND INTERVENTION: A total of 135 consecutive patients who underwent TA-TAVI were included. All patients received catheter-based pain control, either via TEA (TEA group, n=74) or intercostal local analgesia with a catheter placed at the surgical incision site (non-TEA group, n=61), depending on the preference of the anaesthesiologist responsible for the case. MAIN OUTCOME MEASURES: Pain level during early postoperative period (verbal rating scale from 1 to 10), 30-day/in-hospital complications and mortality, and 1-year mortality. RESULTS: There were no differences in baseline or procedural characteristics between groups except for a lower left ventricular ejection fraction in the TEA group. The maximal pain score related to thoracotomy in the postoperative period was higher in the non-TEA group as compared with the TEA group (4 (IQR: 3-5)) vs 2 (IQR: 1-3), p<0.001). Non-TEA was associated with a higher rate of pulmonary complications (p<0.05 for nosocomial pneumonia, reintubation and tracheostomy). The 30-day/in-hospital mortality rate was higher in the non-TEA group (22.9% vs 2.7% in the TEA group, p<0.001). At 1-year follow-up, overall mortality remained higher in the non-TEA group (31.1%) compared with the TEA group (10.8%), p=0.005. Similar periprocedural and late results were obtained in a propensity score-matched analysis that included 100 matched patients. In the multivariable analysis, STS score (p=0.027) and absence of TEA (p=0.039) were independent predictors of increased cumulative late mortality. CONCLUSIONS: TEA provided superior analgesia following TA-TAVI, and was associated with a dramatic reduction in periprocedural respiratory complications, and both, short- and long-term mortality. These results highlight the importance of obtaining optimal analgesia following TA-TAVI to improve the results associated with this procedure.

Usefulness of TEE as the primary imaging technique to guide transcatheter transapical aortic valve implantation.

OBJECTIVES: The aim of this study was to: 1) determine the usefulness of transesophageal echocardiography (TEE) as the primary technique to guide transapical (TA) transcatheter aortic valve implantation (TAVI); and 2) to compare TEE with angiography as the primary imaging modality for TA-TAVI guidance. BACKGROUND: TEE has been routinely used as an adjunct to angiography during TA-TAVI procedures, but very few data exist on the use of TEE as the primary imaging technique guiding TA-TAVI. METHODS: One hundred consecutive high-risk patients (mean age 79 ± 9 years, mean logistic EuroSCORE: 25.8 ± 17.6%) who underwent TA-TAVI in our center were included. The Edwards valve was used in all cases, and all procedures were performed in an operating room without hybrid facilities. The TA-TAVI was primarily guided by angiography in the first 25 patients (A-TAVI group) and by TEE in the last 75 patients (TEE-TAVI group). Procedural, 30-day, and follow-up results were evaluated. RESULTS: No differences were observed between groups at baseline except for a higher (p = 0.001) prevalence of moderate or severe mitral regurgitation in the TEE-TAVI group. The procedure was successful in 97.3% and 100% of the patients in the TEE-TAVI and A-TAVI groups, respectively (p = 1.0), and a lower contrast volume was used in the TEE-TAVI group (12 [5 to 20] ml vs. 40 [20 to 50] ml, p < 0.0001). There were no differences between groups in the occurrence of valve malposition needing a second valve (TEE-TAVI: 5.3%; A-TAVI: 4%; p = 1.0) or valve embolization (TEE-TAVI: 1.3%; A-TAVI: 4%; p = 0.44). The results regarding post-procedural valve hemodynamic status and aortic regurgitation were similar between groups. The survival rates at 30-day and 1-year follow-up were 87% and 75% in the TEE-group and 88% and 84% in the A-TAVI group, respectively (log-rank = 0.49). CONCLUSIONS: TEE-TAVI was associated with similar acute and midterm results as A-TAVI and significantly reduced contrast media use during the procedures. These results suggest the feasibility and safety of performing TA-TAVI procedures in an operating room without hybrid facilities, but larger studies are needed to confirm these findings.

Electrocardiographic changes and clinical outcomes after transapical aortic valve implantation.

BACKGROUND: Transapical aortic valve implantation (TAVI) for the treatment of severe aortic stenosis requires the insertion of a large catheter through the left ventricular apex. However, the electrocardiographic (ECG) changes associated with the incision and repair of the left ventricular apex and the potential damage to the conduction system caused by implanting a balloon-expandable valve in aortic position are not known. The objective of our study was to determine the incidence, type, and timing of ECG changes associated with TAVI. METHODS: The standard 12-lead ECGs of 33 consecutive patients (mean age 81 +/- 9 years, 13 men) diagnosed with symptomatic severe aortic stenosis (valve area 0.62 +/- 0.16 cm(2)) who underwent TAVI with an Edwards-SAPIEN valve were analyzed at baseline (within 24 hours before the procedure), immediately (within 6 hours) after the procedure, at hospital discharge, and at 1-month follow-up. RESULTS: There were no procedural deaths, and 30-day mortality was 6%. The incidence of complete left ventricular branch block (LBBB) and left anterior hemiblock (LAHB) increased from 9% and 3% at baseline to 27% and 36% after the procedure, respectively (P < .03 for both). A lower (ventricular) position of the valve relative to the hinge point of the anterior mitral leaflet was associated with a higher incidence of new LBBB (35% vs 0%, P = .029); and a greater valve size-aortic annulus ratio, with the occurrence of new LAHB (1.20 +/- 0.07 vs 1.14 +/- 0.06, P = .021). At 1-month follow-up, the rate of LBBB and LAHB decreased to 13% and 10%, respectively (P = not significant compared with baseline). There were no cases of new atrioventricular block, and no patient needed pacemaker implantation. Transient (<48 hours) ST-elevation changes, mostly in the anterior and/or lateral leads, occurred in 6 patients (18%) immediately after the procedure; but only 1 of these patients presented new Q waves at 1-month follow-up. CONCLUSIONS: Transapical aortic valve implantation was associated with a significant but transient (<1 month) increase in LBBB and LAHB, with no patient requiring pacemaker implantation. These changes were partially related to both lower (more ventricular) valve positioning and greater valve oversizing. Transient (<48 hours) ST-segment elevation changes occurred in about one fifth of the patients after the procedure, but only a minority developed new Q waves in the ECG.

Rapid pacing technique for preventing ventricular tears during transapical aortic valve replacement.

BACKGROUND: Transapical aortic valve replacement (TAVR) is emerging as an alternative to surgical aortic valve replacement in high-risk or non-operable patients with aortic stenosis. However, this approach might be associated with major bleeding complications during the removal of the introducer sheath from the left ventricular apex. We describe a simple technique to minimize this complication. METHODS: The technique consists of installing a temporary pacing Swan-Ganz catheter, using large-needle Ethibond 2-0 sutures with large pledgets for apical pursestrings, and removing the 26F sheath from the ventricular apex tension-free by rapid ventricular pacing (>150 bpm). RESULTS: We have completed 21 TAVR using rapid ventricular pacing. This technique considerably decreased the amount of apical tearing and sutures to be added at the apex. Six of 21 patients had partial ventricular tearing that was amenable to repair using rapid pacing, thereby avoiding urgent cardiopulmonary bypass. CONCLUSION: The present report describes a technique to reduce the occurrence of ventricular tears and major bleeding during TAVR.

Feasibility and initial results of percutaneous aortic valve implantation including selection of the transfemoral or transapical approach in patients with severe aortic stenosis.

The purpose of this study was to evaluate the feasibility and initial results of a multidisciplinary percutaneous aortic valve implantation (PAVI) program including the transfemoral approach (TFA) and the transapical approach (TAA). This was a prospective registry including all patients with symptomatic severe aortic stenosis who were evaluated for PAVI and those who finally underwent the procedure. All patients were considered very high risk or nonsurgical candidates, and an algorithm based on prespecified criteria was used to determine the most appropriate approach (TFA vs TAA) for each patient. The Edwards-Sapien valve was used in all cases, and all procedures were performed without cardiopulmonary bypass. A total of 29 consecutive patients were evaluated for PAVI, and 22 of them underwent the procedure (mean age 84 +/- 7 years, predicted surgical mortality 26 +/- 16%), with 11 patients selected for each approach. Reasons for selecting TAA rather than TFA were the following: small diameter and/or severe calcification of the iliofemoral arteries (4 patients), peripheral vascular disease (4 patients), porcelain aorta (2 patients), and horizontal ascending aorta (1 patient). Successful aortic valve implantation was obtained in 91% of the procedures, and procedural and 30-day mortality were 4.3% and 8.7%, respectively. There were no cases of myocardial infarction, vascular complications, or cerebrovascular accident. PAVI was associated with a significant reduction in mean aortic gradient (baseline 34 +/- 10 mm Hg, postprocedure 9 +/- 3 mm Hg, p <0.001), with no cases of severe aortic regurgitation. After a median follow-up period of 6 months, there were no additional major adverse cardiac events, and no significant changes in hemodynamic aortic valve parameters were observed. In conclusion, this study demonstrates the feasibility and low complication rate of a PAVI program using a prospective strategy for the selection of the TFA or TAA, with half of the patients selected for each approach.

The role of recombinant factor VIIa in on-pump cardiac surgery: proceedings of the Canadian Consensus Conference.

PURPOSE: Recombinant activated factor VII (rFVIIa) is currently not approved by Health Canada or the Food and Drug Administration for treating excessive blood loss in nonhemophiliac patients undergoing on-pump cardiac surgery, but is increasingly being used "off-label" for this indication. A Canadian Consensus Conference was convened to generate recommendations for rFVIIa use in on-pump cardiac surgery. METHODS: The panel undertook a literature review of the use of rFVIIa in both cardiac and non-cardiac surgery. Appropriateness, timing, and dosage considerations were addressed for three cardiac surgery indications: prophylactic, routine, and rescue uses. Recommendations were based on evidence from the literature and derived by consensus following recognized grading procedures. RESULTS: The panel recommended against prophylactic or routine use of rFVIIa, as there is no evidence at this time that the benefits of rFVIIa outweigh its potential risks compared with standard hemostatic therapies. On the other hand, the panel made a weak recommendation (grade 2C) for the use of rFVIIa (one to two doses of 35-70 microg.kg(-1)) as rescue therapy for blood loss that is refractory to standard hemostatic therapies, despite the lack of randomized controlled trial data for this indication. CONCLUSIONS: In cardiac surgery, the risks and benefits of rFVIIa are unclear, but current evidence suggests that its benefits may outweigh its risks for rescue therapy in selected patients. Methodologically rigorous studies are needed to clarify its riskbenefit profile in cardiac surgery patients.

Modified right-sided Broncho-Cath double lumen tube improves endobronchial positioning: a randomized study.

OBJECTIVE: A left-sided double lumen tube is recommended for one-lung ventilation for most thoracic surgeries, but for certain indications, a right-sided double lumen tube (R-DLT) may be mandatory. Frequent malposition of R-DLTs has been reported. We propose an innovative modification of Mallinckrodt's Broncho-Cath R-DLT consisting of an enlarged area of the lateral orifice, and studied the impact of this modification on the adequacy of R-DLT positioning. METHODS: Eighty adult patients scheduled for elective thoracic surgery were randomized into two groups: standard Broncho-Cath R-DLT, or modified Broncho-Cath R-DLT. After induction of anesthesia, the R-DLT was positioned using a fibreoptic bronchoscope. The position of the R-DLT was assessed on three occasions: with the patient supine (T1), then immediately following the patient's transfer to the lateral position (T2), and after repositioning of the tube, when needed, with the patient in lateral position (T3). A score ranging from 1 to 4 was accorded to the relative position of the right upper lobe (RUL) orifice in relation to the origin of the RUL bronchus. RESULTS: The modified Broncho-Cath R-DLT was more frequently in an adequate position at T2: 77% vs 37% of patients (P = 0.0121), and easier to reposition at T3: 97% vs 74% of patients (P = 0.0109) in comparison to the standard Broncho-Cath R-DLT group. CONCLUSION: These data suggest the superiority of the modified Broncho-Cath R-DLT compared to a standard Broncho-Cath R-DLT for optimal R-DLT positioning to facilitate one-lung ventilation during thoracic surgery.