Five-Year Sustained Impact of a Thoracic Enhanced Recovery After Surgery Program.

BACKGROUND: Our thoracic enhanced recovery program (ERP) decreased the use of postoperative morphine equivalents and hospital costs 1 year after implementation at our tertiary center. The sustainability and potential increasing benefit of this program were evaluated. METHODS: From 2015 to 2021, we prospectively analyzed the outcomes of patients who underwent elective pleural, pulmonary, or mediastinal operations at our institution. Patients were separated on the basis of the incision (video-assisted thoracoscopic surgery [VATS] or thoracotomy). The ERP protocol was initiated on May 1, 2016, and includes preoperative education, carbohydrate loading, opioid-sparing analgesia, conservative fluid management, protective ventilation, and early ambulation. Outcomes of patients before (2015, pre-VATS and pre-thoracotomy) and after (May 1, 2016, to December 31, 2021, ERP-VATS and ERP-thoracotomy) ERP implementation were compared. RESULTS: The cohort included 1079 patients (pre-ERP era, n = 224 [21%]; ERP era, n = 855 [79%]). There was a median reduction of 1.5 hospital days per patient for ERP-thoracotomy and 1 hospital day per patient for ERP-VATS. Median postoperative morphine equivalents decreased in both groups (125 vs 45 mg, in ERP-thoracotomy; 84 vs 23 mg, ERP-VATS; P < .001), as did total admission cost ($32,118 vs $23,775, ERP-thoracotomy; $17,367 vs $11,560, ERP-VATS; P < .001). Median total fluid balance during the hospital stay decreased significantly. Rates of postoperative atrial fibrillation and urinary retention decreased across both subgroups. CONCLUSIONS: ERP for thoracic surgery is sustainable and has been demonstrated to improve patient outcomes, to decrease opioid use, and to lower hospital costs. Therefore, it has the potential to become the standard of care.

Association of Mechanical Energy and Power with Postoperative Pulmonary Complications in Lung Resection Surgery: A Post Hoc Analysis of Randomized Clinical Trial Data.

BACKGROUND: Mechanical power (MP), the rate of mechanical energy (ME) delivery, is a recently introduced unifying ventilator parameter consisting of tidal volume, airway pressures, and respiratory rates, which predicts pulmonary complications in several clinical contexts. However, ME has not been previously studied in the perioperative context, and neither parameter has been studied in the context of thoracic surgery utilizing one-lung ventilation. METHODS: The relationships between ME variables and postoperative pulmonary complications were evaluated in this post hoc analysis of data from a multicenter randomized clinical trial of lung resection surgery conducted between 2020 and 2021 (n = 1,170). Time-weighted average MP and ME (the area under the MP time curve) were obtained for individual patients. The primary analysis was the association of time-weighted average MP and ME with pulmonary complications within 7 postoperative days. Multivariable logistic regression was performed to examine the relationships between energy variables and the primary outcome. RESULTS: In 1,055 patients analyzed, pulmonary complications occurred in 41% (431 of 1,055). The median (interquartile ranges) ME and time-weighted average MP in patients who developed postoperative pulmonary complications versus those who did not were 1,146 (811 to 1,530) J versus 924 (730 to 1,240) J (P < 0.001), and 6.9 (5.5 to 8.7) J/min versus 6.7 (5.2 to 8.5) J/min (P = 0.091), respectively. ME was independently associated with postoperative pulmonary complications (ORadjusted, 1.44 [95% CI, 1.16 to 1.80]; P = 0.001). However, the association between time-weighted average MP and postoperative pulmonary complications was time-dependent, and time-weighted average MP was significantly associated with postoperative pulmonary complications in cases utilizing longer periods of mechanical ventilation (210 min or greater; ORadjusted, 1.46 [95% CI, 1.11 to 1.93]; P = 0.007). Normalization of ME and time-weighted average MP either to predicted body weight or to respiratory system compliance did not alter these associations. CONCLUSIONS: ME and, in cases requiring longer periods of mechanical ventilation, MP were independently associated with postoperative pulmonary complications in thoracic surgery.

Acute Respiratory Failure Complicating Endoscopic Sleeve Gastroplasty: A Case Report.

Endoscopic sleeve gastroplasty (ESG) is a safe and minimally invasive procedure for the treatment of obesity. We report the case of a patient with obesity who underwent ESG complicated by postprocedural respiratory failure. During the procedure, she developed a Pao2/fraction of inspired oxygen (Fio2) ratio that necessitated postoperative mechanical ventilation. Chest radiography demonstrated massively dilated loops of bowel, cephalad displacement of both hemidiaphragms, lung volume reduction, and atelectasis. With absorption of luminal carbon dioxide, she was weaned from mechanical ventilation to supplemental oxygen, and she recovered completely. This case highlights postoperative respiratory failure associated with mechanical loading of the respiratory system following ESG.

Clinical implications of preoperative echocardiographic findings on cardiovascular outcomes following vascular surgery: An observational trial.

INTRODUCTION: Peripheral artery disease and cardiac disease are often comorbid conditions. Echocardiography is a diagnostic tool that can be performed preoperatively to risk stratify patients by a functional cardiac test. We hypothesized that ventricular dysfunction and valvular lesions were associated with an increased incidence of expanded major adverse cardiac events (Expanded MACE). METHODS AND MATERIALS: Retrospective cohort study from 2011 to 2020 including all patients from a major academic center who had vascular surgery and an echocardiographic study within two years of the index procedure. RESULTS: 813 patients were included in the study; a majority had a history of smoking (86%), an ASA score of 3 (65%), and were male (68%). Carotid endarterectomy was the most common surgery (24%) and the least common surgery was open abdominal aortic aneurysm repair (5%). We found no significant association between the echocardiographic findings of left ventricular dysfunction, right ventricular dysfunction, or valvular lesions and the postoperative development of Expanded MACE. CONCLUSIONS: The preoperative echocardiographic findings of left ventricular dysfunction, right ventricular dysfunction and moderate to severe valvular lesions were not predictive of an increased incidence of postoperative Expanded MACE. We identified a significant association between RV dysfunction and post-operative dialysis that should be interpreted carefully due to the small number of outcomes. The transition from open to endovascular surgery and advances in perioperative management may have led to improved cardiovascular outcomes. TRIAL REGISTRATION: Trial Registration: NCT04836702 (clinicaltrials.gov). https://www.google.com/search?client=firefox-b-d&q=NCT04836702.

Enhanced Recovery Protocol Associated With Decreased 3-Month Opioid Use After Thoracic Surgery.

BACKGROUND: Enhanced recovery protocols (ERPs) have been shown to decrease inhospital opioid use after thoracic surgery. However, the impact on opioid use after discharge has not been reported. We hypothesized that prolonged opioid use would decrease after implementation of a comprehensive ERP. METHODS: Records from all patients undergoing elective pulmonary, pleural, and mediastinal operations at a single institution (2015-2018) were abstracted from a prospective ERP database and The Society of Thoracic Surgeons institutional database. Records were reviewed for documentation of opioid use at 3-month and 6-month postoperative visits. Patients with preoperative chronic opioid use were excluded. Univariate analysis compared patients with and patients without 3-month opioid use, and a multivariable logistic regression evaluated independent predictors of prolonged opioid use. RESULTS: A total of 499 patients was included: 160 pre-ERP, and 339 post-ERP. Three-month opioid use rates were decreased after implementation of an ERP (44% vs 30%, P = .01); 6-month opioid use rates were not significantly different (25% vs 18%, P = .10). Univariate analysis demonstrated increased 3-month opioid use rates among patients with preoperative tobacco use (38% vs 27%, P = .05) and chronic pain disorder (88% vs 32%, P < .01), with no impact from surgical incision (video-assisted thoracoscopic surgery 33%; open 37%, P = .49). On multivariable analysis, participation in an ERP was independently associated with decreased opioid use at 3 months (odds ratio 0.53; 95% CI, 0.31-0.89; P = .02). CONCLUSIONS: There is a high burden of prolonged opioid use after elective thoracic surgery. Participation in a comprehensive ERP is associated with decreased opioid use 3 months postoperatively.

Driving pressure-guided ventilation and postoperative pulmonary complications in thoracic surgery: a multicentre randomised clinical trial.

BACKGROUND: Airway driving pressure, easily measured as plateau pressure minus PEEP, is a surrogate for alveolar stress and strain. However, the effect of its targeted reduction remains unclear. METHODS: In this multicentre trial, patients undergoing lung resection surgery were randomised to either a driving pressure group (n=650) receiving an alveolar recruitment/individualised PEEP to deliver the lowest driving pressure or to a conventional protective ventilation group (n=650) with fixed PEEP of 5 cm H2O. The primary outcome was a composite of pulmonary complications within 7 days postoperatively. RESULTS: The modified intention-to-treat analysis included 1170 patients (mean [standard deviation, sd]; age, 63 [10] yr; 47% female). The mean driving pressure was 7.1 cm H2O in the driving pressure group vs 9.2 cm H2O in the protective ventilation group (mean difference [95% confidence interval, CI]; -2.1 [-2.4 to -1.9] cm H2O; P<0.001). The incidence of pulmonary complications was not different between the two groups: driving pressure group (233/576, 40.5%) vs protective ventilation group (254/594, 42.8%) (risk difference -2.3%; 95% CI, -8.0% to 3.3%; P=0.42). Intraoperatively, lung compliance (mean [sd], 42.7 [12.4] vs 33.5 [11.1] ml cm H2O-1; P<0.001) and Pao2 (median [inter-quartile range], 21.5 [14.5 to 30.4] vs 19.5 [13.5 to 29.1] kPa; P=0.03) were higher and the need for rescue ventilation was less frequent (6.8% vs 10.8%; P=0.02) in the driving pressure group. CONCLUSIONS: In lung resection surgery, a driving pressure-guided ventilation improved pulmonary mechanics intraoperatively, but did not reduce the incidence of postoperative pulmonary complications compared with a conventional protective ventilation. CLINICAL TRIAL REGISTRATION: NCT04260451.

Mediastinal Masses, Anesthetic Interventions, and Airway Compression in Adults: A Prospective Observational Study.

BACKGROUND: Central airway occlusion is a feared complication of general anesthesia in patients with mediastinal masses. Maintenance of spontaneous ventilation and avoiding neuromuscular blockade are recommended to reduce this risk. Physiologic arguments supporting these recommendations are controversial and direct evidence is lacking. The authors hypothesized that, in adult patients with moderate to severe mediastinal mass-mediated tracheobronchial compression, anesthetic interventions including positive pressure ventilation and neuromuscular blockade could be instituted without compromising central airway patency. METHODS: Seventeen adult patients with large mediastinal masses requiring general anesthesia underwent awake intubation followed by continuous video bronchoscopy recordings of the compromised portion of the airway during staged induction. Assessments of changes in anterior-posterior airway diameter relative to baseline (awake, spontaneous ventilation) were performed using the following patency scores: unchanged = 0; 25 to 50% larger = +1; more than 50% larger = +2; 25 to 50% smaller = -1; more than 50% smaller = -2. Assessments were made by seven experienced bronchoscopists in side-by-side blinded and scrambled comparisons between (1) baseline awake, spontaneous breathing; (2) anesthetized with spontaneous ventilation; (3) anesthetized with positive pressure ventilation; and (4) anesthetized with positive pressure ventilation and neuromuscular blockade. Tidal volumes, respiratory rate, and inspiratory/expiratory ratio were similar between phases. RESULTS: No significant change from baseline was observed in the mean airway patency scores after the induction of general anesthesia (0 [95% CI, 0 to 0]; P = 0.953). The mean airway patency score increased with the addition of positive pressure ventilation (0 [95% CI, 0 to 1]; P = 0.024) and neuromuscular blockade (1 [95% CI, 0 to 1]; P < 0.001). No patient suffered airway collapse or difficult ventilation during any anesthetic phase. CONCLUSIONS: These observations suggest a need to reassess prevailing assumptions regarding positive pressure ventilation and/or paralysis and mediastinal mass-mediated airway collapse, but do not prove that conventional (nonstaged) inductions are safe for such patients.

Airway driving pressure is associated with postoperative pulmonary complications after major abdominal surgery: a multicentre retrospective observational cohort study.

Background: High airway driving pressure is associated with adverse outcomes in critically ill patients receiving mechanical ventilation, but large multicentre studies investigating airway driving pressure during major surgery are lacking. We hypothesised that increased driving pressure is associated with postoperative pulmonary complications in patients undergoing major abdominal surgery. Methods: In this preregistered multicentre retrospective observational cohort study, the authors reviewed major abdominal surgical procedures in 11 hospitals from 2004 to 2018. The primary outcome was a composite of postoperative pulmonary complications, defined as postoperative pneumonia, unplanned tracheal intubation, or prolonged mechanical ventilation for more than 48 h. Associations between intraoperative dynamic driving pressure and outcomes, adjusted for patient and procedural factors, were evaluated. Results: Among 14 218 qualifying cases, 389 (2.7%) experienced postoperative pulmonary complications. After adjustment, the mean dynamic driving pressure was associated with postoperative pulmonary complications (adjusted odds ratio for every 1 cm H2O increase: 1.04; 95% confidence interval [CI], 1.02-1.06; P<0.001). Neither tidal volume nor PEEP was associated with postoperative pulmonary complications. Increased BMI, shorter height, and female sex were predictors for higher dynamic driving pressure (ß=0.35, 95% CI 0.32-0.39, P<0.001; ß=-0.01, 95% CI -0.02 to 0.00, P=0.005; and ß=0.74, 95% CI 0.63-0.86, P<0.001, respectively). Conclusions: Dynamic airway driving pressure, but not tidal volume or PEEP, is associated with postoperative pulmonary complications in models controlling for a large number of risk predictors and covariates. Such models are capable of risk prediction applicable to individual patients.

A Lower Tidal Volume Regimen during One-lung Ventilation for Lung Resection Surgery Is Not Associated with Reduced Postoperative Pulmonary Complications.

BACKGROUND: Protective ventilation may improve outcomes after major surgery. However, in the context of one-lung ventilation, such a strategy is incompletely defined. The authors hypothesized that a putative one-lung protective ventilation regimen would be independently associated with decreased odds of pulmonary complications after thoracic surgery. METHODS: The authors merged Society of Thoracic Surgeons Database and Multicenter Perioperative Outcomes Group intraoperative data for lung resection procedures using one-lung ventilation across five institutions from 2012 to 2016. They defined one-lung protective ventilation as the combination of both median tidal volume 5 ml/kg or lower predicted body weight and positive end-expiratory pressure 5 cm H2O or greater. The primary outcome was a composite of 30-day major postoperative pulmonary complications. RESULTS: A total of 3,232 cases were available for analysis. Tidal volumes decreased modestly during the study period (6.7 to 6.0 ml/kg; P < 0.001), and positive end-expiratory pressure increased from 4 to 5 cm H2O (P < 0.001). Despite increasing adoption of a "protective ventilation" strategy (5.7% in 2012 vs. 17.9% in 2016), the prevalence of pulmonary complications did not change significantly (11.4 to 15.7%; P = 0.147). In a propensity score matched cohort (381 matched pairs), protective ventilation (mean tidal volume 6.4 vs. 4.4 ml/kg) was not associated with a reduction in pulmonary complications (adjusted odds ratio, 0.86; 95% CI, 0.56 to 1.32). In an unmatched cohort, the authors were unable to define a specific alternative combination of positive end-expiratory pressure and tidal volume that was associated with decreased risk of pulmonary complications. CONCLUSIONS: In this multicenter retrospective observational analysis of patients undergoing one-lung ventilation during thoracic surgery, the authors did not detect an independent association between a low tidal volume lung-protective ventilation regimen and a composite of postoperative pulmonary complications.

Development and Impact of an Institutional Enhanced Recovery Program on Opioid Use, Length of Stay, and Hospital Costs Within an Academic Medical Center: A Cohort Analysis of 7774 Patients.

BACKGROUND: Enhanced Recovery (ER) is a change management framework in which a multidisciplinary team of stakeholders utilizes evidence-based medicine to protocolize all aspects of a surgical care to allow more rapid return of function. While service-specific reports of ER adoption are common, institutional-wide adoption is complex, and reports of institution-wide ER adoption are lacking in the United States. We hypothesized that ER principles were generalizable across an institution and could be implemented across a multitude of surgical disciplines with improvements in length of stay, opioid consumption, and cost of care. METHODS: Following the establishment of a formal institutional ER program, ER was adopted in 9 distinct surgical subspecialties over 5 years at an academic medical center. We compared length of stay, opioid consumption, and total cost of care in all surgical subspecialties as a function of time using a segmented regression/interrupted time series statistical model. RESULTS: There were 7774 patients among 9 distinct surgical populations including 2155 patients in the pre-ER cohort and 5619 patients in the post-ER cohort. The introduction of an ER protocol was associated with several significant changes: a reduction in length of stay in 5 of 9 specialties; reduction in opioid consumption in 8 specialties; no change or reduction in maximum patient-reported pain scores; and reduction or no change in hospital costs in all specialties. The ER program was associated with an aggregate increase in profit over the study period. CONCLUSIONS: Institution-wide efforts to adopt ER can generate significant improvements in patient care, opioid consumption, hospital capacity, and profitability within a large academic medical center.

Peripheral Cardiopulmonary Bypass in Two Patients With Symptomatic Tracheal Masses: Perioperative Challenges.

Tracheal tumors or masses causing critical airway obstruction require resection for symptom relief. However, the location and extent of these tumors or masses often preclude conventional general anesthesia and tracheal intubation. Peripheral cardiopulmonary bypass often is required before anesthetizing these patients. Herein, two cases of patients with tracheal masses, in whom awake peripheral cardiopulmonary bypass was instituted, are reported. The first case was that of an obese male child weighing 102 kg, with tracheal rhinoscleroma, who developed Harlequin, or north-south, syndrome after institution of femorofemoral venoarterial partial cardiopulmonary bypass. The second case was that of a female patient with adenoid cystic carcinoma of the trachea causing near-total central airway occlusion. She had severe pulmonary artery hypertension, which prevented the use of venovenous bypass. Instead, femoral vein-axillary artery venoarterial bypass was established to avoid Harlequin syndrome. Some of the challenges encountered were the development of Harlequin syndrome with risk of myocardial and cerebral ischemia, type and conduct of extracorporeal bypass, choice of monitoring sites, and provision of regional anesthesia for peripheral extracorporeal cannulations. Management of such patients needs frequent troubleshooting and multidisciplinary coordination for a successful surgical outcome.

An Observational Study of the Pharmacokinetics of Surgeon-Performed Intercostal Nerve Blockade With Liposomal Bupivacaine for Posterior-Lateral Thoracotomy Analgesia.

BACKGROUND: Intercostal nerve blocks with liposomal bupivacaine are commonly used for thoracic surgery pain management. However, dose scheduling is difficult because the pharmacokinetics of a single-dose intercostal injection of liposomal bupivacaine has never been investigated. The primary aim of this study was to assess the median time to peak plasma concentration (Tmax) following a surgeon-administered, single-dose infiltration of 266 mg of liposomal bupivacaine as a posterior multilevel intercostal nerve block in patients undergoing posterolateral thoracotomy. METHODS: We chose a sample size of 15 adults for this prospective observational study. Intercostal injection of liposomal bupivacaine was considered time 0. Serum samples were taken at the following times: 5, 15, and 30 minutes, and 1, 2, 4, 8, 12, 24, 48, 72, and 96 hours. The presence of sensory blockade, rescue pain medication, and pain level were recorded after the patient was able to answer questions. RESULTS: Forty patients were screened, and 15 patients were enrolled in the study. Median (interquartile range [IQR]) Tmax was 24 (12) hours (confidence interval [CI], 19.5-28.5 hours) with a range of 15 minutes to 48 hours. The median (IQR) peak plasma concentration (Cmax) was 0.6 (0.3) µg/mL (CI, 00.45-0.74 µg/mL) in a range of 0.3-1.2. The serum bupivacaine concentration was undetectable (<0.2 µg/mL) at 96 hours in all patients. There was significant variability in reported pain scores and rescue opioid medication across the 15 patients. More than 50% of patients had return of normal chest wall sensation at 48 hours. All patients had resolution of nerve blockade at 96 hours. No patients developed local anesthetic toxicity. CONCLUSIONS: This study of the pharmacokinetics of liposomal bupivacaine following multilevel intercostal nerve blockade demonstrates significant variability and delay in systemic absorption of the drug. Peak serum concentration occurred at 48 hours or sooner in all patients. The serum bupivacaine concentration always remained well below the described toxicity threshold (2 µg/mL) during the 96-hour study period.

Enhanced Recovery After Thoracic Surgery.

Enhanced recovery pathways (ERPs), used across multiple surgical subspecialties, is a multidisciplinary delivery of perioperative care designed to lessen the psychological stress of patients undergoing surgery. Thoracic ERP has been implemented but is not widespread, and variations exist between programs. Evidence of the benefit of thoracic ERP is emerging. This article presents common components of a thoracic surgery ERP and reviews contemporary outcomes.

Is less really more? Reexamining video-assisted thoracoscopic versus open lobectomy in the setting of an enhanced recovery protocol.

OBJECTIVES: Video-assisted thoracoscopic surgery lobectomy has been associated with improved pain, length of stay, and outcomes compared with open lobectomy. However, enhanced recovery protocols improve outcomes after both procedures. We aimed to compare video-assisted thoracoscopic surgery and open lobectomy in the setting of a comprehensive enhanced recovery protocol. METHODS: All patients undergoing lobectomy for lung cancer at a single institution since the adoption of an enhanced recovery protocol (May 2016 to December 2018) were stratified by video-assisted thoracoscopic surgery versus open status and compared. Demographics and outcomes, including length of stay, daily pain scores, and short-term operative complications, were compared using standard univariate statistics and multivariable models. RESULTS: A total of 130 patients underwent lobectomy, including 71 (54.6%) undergoing video-assisted thoracoscopic surgery and 59 (45.4%) undergoing open surgery. Video-assisted thoracoscopic surgery versus open cases exhibited similar length of stay (median 4 days for both, P = .07), opioid requirement (33.2 vs 30.8 mg morphine equivalents, P = .86), and pain scores at 0, 1, 2, and 3 days after surgery (4.3 vs 2.8, P = .12; 4.4 vs 3.7, P = .27; 3.9 vs 3.5, P = .83; and 3.4 vs 3.5, P = .98, respectively). Patients undergoing video-assisted thoracoscopic surgery lobectomy exhibited lower rates of readmission (1.4% vs 17.0%, P < .01), postoperative transfusion requirement (0% vs 10.2%, P < .01), and pneumonia (1.4% vs 10.2%, P = .05). After risk adjustment, an open procedure (vs video-assisted thoracoscopic surgery status) did not significantly affect the length of stay (effect 0.18; P = .10) or overall complication rate (odds ratio, 1.9; P = .12). CONCLUSIONS: In the setting of a comprehensive enhanced recovery protocol, patients undergoing video-assisted thoracoscopic surgery versus open lobectomy exhibited similar short-term outcomes. Surgical incision may have less impact on outcomes in the setting of a comprehensive thoracic enhanced recovery protocol.

Ventilator Mode Does Not Influence Blood Loss or Transfusion Requirements During Major Spine Surgery: A Retrospective Study.

BACKGROUND: Blood loss during adult spinal deformity surgery is multifactorial. Anesthetic-related factors, such as mode of mechanical ventilation, may contribute to intraoperative blood loss. The aim of this study was to determine the influence of ventilator mode and ventilator parameters on intraoperative blood loss and transfusion requirements in patients undergoing prone position spine surgery. METHODS: This single-center retrospective study examined electronic medical records of patients ≥18 years of age who underwent elective prone position spine surgery between May 2015 and June 2016. Associations between ventilator mode and ventilator parameters with intraoperative estimated blood loss (EBL), packed red blood cells (PRBCs), fresh-frozen plasma (FFP), cryoprecipitate and platelet transfusions, and subfascial drain output were examined using multiple linear regression models controlling for age, sex, American Society of Anesthesiologist (ASA) physical status score, body mass index (BMI), preoperative blood coagulation parameters and laboratory values, operative levels, cage constructs, osteotomies, transforaminal lumbar interbody fusions, laminectomies, reoperation, spine surgery invasiveness index, and operative time. In a secondary analysis, EBL, blood product transfusions, and postoperative drain output were compared between pressure-controlled ventilation (PCV) and volume-controlled ventilation (VCV) propensity score-matched cohorts. RESULTS: Nine hundred forty-six records were reviewed, and 822 were included in the analysis. After adjusting for confounding, no statistically significant associations were observed between mode of ventilation and intraoperative EBL (estimate, -2; 95% confidence interval [CI], -248 to 245; P = .99) or blood product transfusions (PRBC: estimate, -9; 95% CI, -154 to 135; P = .90; FFP: estimate, -3; 95% CI, -59 to 54; P = .93; cryoprecipitate: estimate, -14; 95% CI, -70 to 43; P = .63; platelets: -7; 95% CI, -39 to 24; P = .64). After propensity score matching (n = 27 per group), no significant differences were observed in EBL (mean difference, 525 mL; 95% CI, -15 to 1065; P = .056) or blood transfusions (PRBC: mean difference, 208 mL; 95% CI, -23 to 439; P = .077; FFP (mean difference, 34 mL; 95% CI, -17 to 84; P = .19); cryoprecipitate (mean difference, 55 mL; 95% CI, -24 to 133; P = .17); or platelets (mean difference, 26 mL; 95% CI, -12 to 64; P = .18) between PCV and VCV groups. CONCLUSIONS: In prone position spine surgery, neither mode of mechanical ventilation nor airway pressure is associated with intraoperative blood loss or need for allogeneic transfusion. Use of modern ventilation strategies using lung protective techniques may mitigate differences in blood loss previously observed between PCV and VCV modes.

Detection of intratracheal accumulation of thick secretions by using continuous monitoring of respiratory acoustic spectrum: a preliminary analysis.

The accumulation of tracheobronchial secretions may contribute to a deterioration in pulmonary function and its early detection is important. In this study, we analyzed the respiratory sound spectrum in patients with intratracheal secretion, and compared acoustic characteristics before and after therapeutic endotracheal suctioning. After review of anesthetic records of liver transplant recipients, we included recipients with identified intratracheal secretion during surgery. Intraoperative breath sounds recorded through esophageal stethoscope were sampled in 20 s-period before and after suctioning of secretion and analyzed using fast Fourier transform. We also analyzed normal breath sounds from recipients without any respiratory problem as control group. The maximal power (dBmMax), total power from whole frequency range of 80-500 Hz (Pt), total power of each frequency range (80-200 Hz, P80-200; 200-300 Hz, P200-300; 300-400 Hz, P300-400; 400-500 Hz, P400-500), and their ratio (P80-200/Pt, P200-300/Pt, P300-400/Pt, P400-500/Pt) were compared. Breath sounds were obtained from 20 recipients; 9 pairs of breath sound before and after suctioning of secretion and 11 normal breath sounds. Patients with intratracheal secretion showed significantly higher P80-200, P200-300, P300-400, P400-500 when compared to the those of normal control patients (P = 0.003, P = 0.002, and P = 0.009, respectively), while dBmMax did not differ. Elimination of secretions attenuated P80-200, P200-300, P300-400, and P400-500 by 22.4%, 25.7%, 48.5%, and 15.3%, respectively (P = 0.002, 0.024, 0.009, and 0.016, respectively). Identifying the presence of intratracheal secretions with power ratio at 80-200 Hz and 300-400 Hz showed the highest area under the curve of 0.955 in receiver operating characteristic curve analysis. We suggest that spectral analysis of breath sounds obtained from the esophageal stethoscope might be a useful non-invasive respiratory monitor for accumulation of intratracheal secretion. Further prospective studies to evaluate the utility of acoustic analysis in surgical patients are warranted.

Intraoperative Mechanical Ventilation and Postoperative Pulmonary Complications after Cardiac Surgery.

BACKGROUND: Compared with historic ventilation strategies, modern lung-protective ventilation includes lower tidal volumes (VT), lower driving pressures, and application of positive end-expiratory pressure (PEEP). The contributions of each component to an overall intraoperative protective ventilation strategy aimed at reducing postoperative pulmonary complications have neither been adequately resolved, nor comprehensively evaluated within an adult cardiac surgical population. The authors hypothesized that a bundled intraoperative protective ventilation strategy was independently associated with decreased odds of pulmonary complications after cardiac surgery. METHODS: In this observational cohort study, the authors reviewed nonemergent cardiac surgical procedures using cardiopulmonary bypass at a tertiary care academic medical center from 2006 to 2017. The authors tested associations between bundled or component intraoperative protective ventilation strategies (VT below 8 ml/kg ideal body weight, modified driving pressure [peak inspiratory pressure - PEEP] below 16 cm H2O, and PEEP greater than or equal to 5 cm H2O) and postoperative outcomes, adjusting for previously identified risk factors. The primary outcome was a composite pulmonary complication; secondary outcomes included individual pulmonary complications, postoperative mortality, as well as durations of mechanical ventilation, intensive care unit stay, and hospital stay. RESULTS: Among 4,694 cases reviewed, 513 (10.9%) experienced pulmonary complications. After adjustment, an intraoperative lung-protective ventilation bundle was associated with decreased pulmonary complications (adjusted odds ratio, 0.56; 95% CI, 0.42-0.75). Via a sensitivity analysis, modified driving pressure below 16 cm H2O was independently associated with decreased pulmonary complications (adjusted odds ratio, 0.51; 95% CI, 0.39-0.66), but VT below 8 ml/kg and PEEP greater than or equal to 5 cm H2O were not. CONCLUSIONS: The authors identified an intraoperative lung-protective ventilation bundle as independently associated with pulmonary complications after cardiac surgery. The findings offer insight into components of protective ventilation associated with adverse outcomes and may serve as targets for future prospective interventional studies investigating the impact of specific protective ventilation strategies on postoperative outcomes after cardiac surgery.