Effect of Sevoflurane Anesthesia on Diastolic Function: A Prospective Observational Study.

BACKGROUND: The effect of sevoflurane on left ventricular diastolic function is not well understood. We hypothesized that parameters of diastolic function may improve under sevoflurane anesthesia in patients with preexisting diastolic dysfunction compared to patients with normal diastolic function. METHODS: This observational study included 60 patients undergoing breast surgery or laparoscopic cholecystectomy. Patients were assigned to diastolic dysfunction (n = 34) or normal (n = 26) groups of septal e' < 8 or ≥ 8.0 cm/s on the first thoracic echocardiography (TTE) performed before anesthesia. During anesthesia, sevoflurane was maintained at 1 to 2 minimum alveolar concentration (MAC) to maintain the bispectral index at 40 to 50. At the end of surgery, the second TTE was performed under 0.8 to 1 MAC of sevoflurane with the patient breathing spontaneously without ventilator support. Primary end point was the percentage change (Δ) of e' on 2 TTEs (Δe'). Secondary end points were ΔE/e', Δleft atrial volume index (ΔLAVI), and Δtricuspid regurgitation maximum velocity (ΔTR Vmax). These percentage changes (Δ) were compared between diastolic dysfunction and normal groups. RESULTS: e' (Δe': 30 [6, 64] vs 0 [-18, 11]%; P < .001), mitral inflow E wave velocity (E), mitral inflow E/A ratio (E/A), and mitral E velocity deceleration time (DT) improved significantly in diastolic dysfunction group compared to normal group. LAVI decreased in diastolic dysfunction group but did not reach statistical significance between the 2 groups (ΔLAVI:-15 [-31, -3] vs -4 [-20, 10]%, P = .091). ΔE/e' was not different between the 2 groups (11 [-16, 26] vs 12 [-9, 22]%, P = .853) (all: median [interquartile range, IQR]). TR was minimal in both groups. CONCLUSIONS: In this study, echocardiographic parameters of diastolic function, including septal e', E, E/A, and DT, improved with sevoflurane anesthesia in patients with preexisting diastolic dysfunction, but remained unchanged in patients with normal diastolic function.

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.

Continuous Titration of Inspired Oxygen Using Oxygen Reserve Index to Decrease Oxygen Exposure During One-Lung Ventilation: A Randomized Controlled Trial.

BACKGROUND: A high fraction of inspired oxygen (Fio2) is administered during one-lung ventilation (OLV). However, a high Fio2 is not physiologic and may lead to various complications. We hypothesized that continuous titration of Fio2 using the oxygen reserve index (ORI) reduces oxygen exposure compared to conventional management during OLV. METHODS: In this randomized, double-blinded trial, patients undergoing thoracic surgery were assigned to an ORI (n = 64) or a control group (n = 60). In the ORI group, ORI was continuously displayed using multiwavelength pulse co-oximetry (Masimo) between 0 and 1 (0, no reserve; 1, maximum reserve), and Fio2 was titrated for a target ORI of 0.21 at 5-minute intervals during OLV. In the control group, Fio2 was adjusted using arterial blood gas analysis measured at 15 minutes after OLV initiation. The primary end point was the time-weighted average Fio2 during OLV. RESULTS: Overall, time-weighted average Fio2 did not differ between the groups (control versus ORI: median [interquartile range], 0.87 [0.73-1.00] vs 0.82 [0.68-0.93]; P = .09). However, in a subgroup analysis, the ORI group reduced time-weighted average Fio2 after pulmonary vascular ligation compared to the control group (control versus ORI: median [interquartile range], 0.75 [0.70-1.00] vs 0.72 [0.59-0.89]; P = .0261). The incidence of intraoperative hypoxia (arterial oxygen saturation [Spo2] <94%; control versus ORI: 32% [19/60; 95% confidence interval (CI), 20-45] vs 19% [12/64; 95% CI, 10-31]; P = .09), and postoperative complications within the first 7 days did not differ between the groups. CONCLUSIONS: ORI-guided continuous Fio2 titration does not reduce overall oxygen exposure during OLV.

Safety of Rigid Bronchoscopy for Therapeutic Intervention at the Intensive Care Unit Bedside.

Background and Objective: Although rigid bronchoscopy is generally performed in the operating room (OR), the intervention is sometimes emergently required at the intensive care unit (ICU) bedside. The aim of this study is to evaluate the safety of rigid bronchoscopy at the ICU bedside. Materials and Methods: We retrospectively analyzed medical records of patients who underwent rigid bronchoscopy while in the ICU from January 2014 to December 2020. According to the location of rigid bronchoscopic intervention, patients were classified into the ICU group (n = 171, cases emergently performed at the ICU bedside without anesthesiologists) and the OR group (n = 165, cases electively performed in the OR with anesthesiologists). The risk of intra- and post-procedural complications in the ICU group was analyzed using multivariable logistic regression, with the OR group as the reference category. Results: Of 336 patients, 175 (52.1%) were moribund and survival was not expected without intervention, and 170 (50.6%) received invasive respiratory support before the intervention. The most common reasons for intervention were post-intubation tracheal stenosis (39.3%) and malignant airway obstruction (34.5%). Although the overall rate of intra-procedural complications did not differ between the two groups (86.0% vs. 80.6%, p = 0.188), post-procedural complications were more frequent in the ICU group than in the OR group (24.0% vs. 12.1%, p = 0.005). Severe complications requiring unexpected invasive management occurred only post-procedurally and were more common in the ICU group (10.5% vs. 4.8%, p = 0.052). In the fully adjusted model, the ICU group had increased odds for severe post-procedural complications, but statistical significance was not observed (odds ratio, 2.54; 95% confidence interval, 0.73-8.88; p = 0.144). Conclusions: Although general anesthesia is generally considered the gold standard for rigid bronchoscopy, our findings indicate that rigid bronchoscopy may be safely performed at the ICU bedside in selective cases of emergency. Moreover, adequate patient selection and close post-procedural monitoring are required to prevent severe complications.

Pressure Support versus Spontaneous Ventilation during Anesthetic Emergence-Effect on Postoperative Atelectasis: A Randomized Controlled Trial.

BACKGROUND: Despite previous reports suggesting that pressure support ventilation facilitates weaning from mechanical ventilation in the intensive care unit, few studies have assessed its effects on recovery from anesthesia. The authors hypothesized that pressure support ventilation during emergence from anesthesia reduces postoperative atelectasis in patients undergoing laparoscopic surgery using the Trendelenburg position. METHODS: In this randomized controlled double-blinded trial, adult patients undergoing laparoscopic colectomy or robot-assisted prostatectomy were assigned to either the pressure support (n = 50) or the control group (n = 50). During emergence (from the end of surgery to extubation), pressure support ventilation was used in the pressure support group versus intermittent manual assistance in the control group. The primary outcome was the incidence of atelectasis diagnosed by lung ultrasonography at the postanesthesia care unit (PACU). The secondary outcomes were Pao2 at PACU and oxygen saturation measured by pulse oximetry less than 92% during 48 h postoperatively. RESULTS: Ninety-seven patients were included in the analysis. The duration of emergence was 9 min and 8 min in the pressure support and control groups, respectively. The incidence of atelectasis at PACU was lower in the pressure support group compared to that in the control group (pressure support vs. control, 16 of 48 [33%] vs. 28 of 49 [57%]; risk ratio, 0.58; 95% CI, 0.35 to 0.91; P = 0.024). In the PACU, Pao2 in the pressure support group was higher than that in the control group (92 ± 26 mmHg vs. 83 ± 13 mmHg; P = 0.034). The incidence of oxygen saturation measured by pulse oximetry less than 92% during 48 h postoperatively was not different between the groups (9 of 48 [19%] vs. 11 of 49 [22%]; P = 0.653). There were no adverse events related to the study protocol. CONCLUSIONS: The incidence of postoperative atelectasis was lower in patients undergoing either laparoscopic colectomy or robot-assisted prostatectomy who received pressure support ventilation during emergence from general anesthesia compared to those receiving intermittent manual assistance.

Association between intraoperative hypotension and postoperative myocardial injury in patients with prior coronary stents undergoing high-risk surgery: a retrospective study.

PURPOSE: We conducted a single-center retrospective study to evaluate the effects of intraoperative hypotension (IOH) on postoperative myocardial injury during major noncardiac surgery in patients with prior coronary stents with preoperatively normal cardiac troponin I levels. Although IOH is assumed to increase the risk of postoperative myocardial injury in patients with prior coronary stents, the level and duration of hazardous low blood pressure have not been clarified. METHODS: Of 2517 patients with prior coronary stents undergoing noncardiac surgery between January 2010 and March 2017, we analyzed 195 undergoing major surgery (vascular, abdominal, and thoracic surgery) who had a normal preoperative high-sensitivity cardiac troponin I (hs-cTnI) level and were followed up postoperatively within 3 days. Postoperative myocardial injury was defined as a hs-cTnI level greater than the 99th percentile reference value. Primary IOH exposure was defined as a decrease of ≥ 50%, 40%, or 30% from the preinduction mean blood pressure. Additional definition of IOH was absolute mean blood pressure < 70, < 60 or < 50 mmHg. Multivariate logistic regression was used to model the exposure and myocardial injury. RESULTS: Myocardial injury occurred in 53 (27.2%) cases. The predefined levels of IOH were not significantly associated with postoperative myocardial injury, but intraoperative continuous inotropes/vasopressors use was significantly higher in patients with myocardial injury (P = 0.004). Operation time ≥ 166 min (OR = 2.823, 95% CI 1.184-6.731, P = 0.019) and abdominal vascular surgery (OR = 2.693, 95% CI 1.213-5.976, P = 0.015) were independent risk factors for myocardial injury. CONCLUSION: Although patients with prior coronary stents with normal hs-cTnI levels did not show association between varying levels of IOH and postoperative myocardial injury after noncardiac surgery, intraoperative need of continuous inotropes/vasopressors was higher in patients with postoperative myocardial injury. Abdominal vascular surgery and surgical time were independent risk factors for myocardial injury after surgery.

Driving Pressure during Thoracic Surgery: A Randomized Clinical Trial.

WHAT WE ALREADY KNOW ABOUT THIS TOPIC: Driving pressure (plateau minus end-expiratory airway pressure) is a target in patients with acute respiratory distress syndrome, and is proposed as a target during general anesthesia for patients with normal lungs. It has not been reported for thoracic anesthesia where isolated, inflated lungs may be especially at risk. WHAT THIS ARTICLE TELLS US THAT IS NEW: In a double-blinded, randomized trial (292 patients), minimized driving pressure compared with standard protective ventilation was associated with less postoperative pneumonia or acute respiratory distress syndrome. BACKGROUND: Recently, several retrospective studies have suggested that pulmonary complication is related with driving pressure more than any other ventilatory parameter. Thus, the authors compared driving pressure-guided ventilation with conventional protective ventilation in thoracic surgery, where lung protection is of the utmost importance. The authors hypothesized that driving pressure-guided ventilation decreases postoperative pulmonary complications more than conventional protective ventilation. METHODS: In this double-blind, randomized, controlled study, 292 patients scheduled for elective thoracic surgery were included in the analysis. The protective ventilation group (n = 147) received conventional protective ventilation during one-lung ventilation: tidal volume 6 ml/kg of ideal body weight, positive end-expiratory pressure (PEEP) 5 cm H2O, and recruitment maneuver. The driving pressure group (n = 145) received the same tidal volume and recruitment, but with individualized PEEP which produces the lowest driving pressure (plateau pressure-PEEP) during one-lung ventilation. The primary outcome was postoperative pulmonary complications based on the Melbourne Group Scale (at least 4) until postoperative day 3. RESULTS: Melbourne Group Scale of at least 4 occurred in 8 of 145 patients (5.5%) in the driving pressure group, as compared with 18 of 147 (12.2%) in the protective ventilation group (P = 0.047, odds ratio 0.42; 95% CI, 0.18 to 0.99). The number of patients who developed pneumonia or acute respiratory distress syndrome was less in the driving pressure group than in the protective ventilation group (10/145 [6.9%] vs. 22/147 [15.0%], P = 0.028, odds ratio 0.42; 95% CI, 0.19 to 0.92). CONCLUSIONS: Application of driving pressure-guided ventilation during one-lung ventilation was associated with a lower incidence of postoperative pulmonary complications compared with conventional protective ventilation in thoracic surgery.

Intraoperative use of dexmedetomidine for the prevention of emergence agitation and postoperative delirium in thoracic surgery: a randomized-controlled trial.

PURPOSE: We investigated whether preventive use of dexmedetomidine during surgery was effective for reducing emergence agitation and postoperative delirium. METHODS: In this double-blind randomized-controlled trial, 143 patients undergoing thoracoscopic lung resection surgery were randomly assigned to the dexmedetomidine-sevoflurane (DEX-Sevo, n = 73) or sevoflurane (Sevo, n = 70) groups. Dexmedetomidine or saline administration was started after inducing anesthesia and continued until the end of surgery at a fixed dose (0.5 µg·kg-1·hr-1). The primary endpoint was the incidence of delirium up until the end of postoperative day 3. Emergence agitation and postoperative delirium were measured with the Riker sedation agitation scale and the confusion assessment method, respectively. The secondary endpoints were serum cytokine and catecholamine levels. RESULTS: The DEX-Sevo group showed less frequent emergence agitation than the Sevo group (13% vs 35%, respectively; relative risk, 0.38; 95% confidence interval [CI], 0.18 to 0.79; P = 0.011) but the incidence of delirium after discharge from the postanesthesia care unit was not different (25% vs 25%, DEX-Sevo vs Sevo). Both pro- and anti-inflammatory cytokines were lower in the DEX-Sevo group than in the Sevo group. Nevertheless, the interleukin (IL)6/IL10 ratio (median difference, 5.8; 95% CI,1.8 to 10.0; P = 0.012) and IL8/IL10 ratio (median difference, 0.8; 95% CI, 0.2 to 1.3; P = 0.007) were higher in the DEX-Sevo group than in the Sevo group, indicating a pro-inflammatory cytokine balance in the DEX-Sevo group. Norepinephrine and epinephrine levels were lower in the DEX-Sevo group than in the Sevo group (both, P < 0.001). CONCLUSIONS: Intraoperative dexmedetomidine reduced emergence agitation but not postoperative delirium in patients undergoing thoracic surgery. Dexmedetomidine seemed to affect emergence agitation through catecholamines, but not through an anti-inflammatory action. Trial registration Clinical Research Information Service (KCT 0001877); registered 7 April, 2016.

RéSUMé: OBJECTIF: Nous avons cherché à savoir si l'utilisation préventive de dexmédétomidine au cours de la chirurgie pouvait réduire la survenue de l'agitation au réveil et du delirium postopératoire. MéTHODES: Dans cette étude randomisée, contrôlée à double insu, 143 patients subissant une résection pulmonaire par thoracoscopie ont été randomisés dans un groupe recevant dexmédétomidine-sévoflurane (DEX-Sévo, n = 73) ou dans un groupe recevant seulement du sévoflurane (Sévo, n = 70). L'administration de dexmédétomidine ou de solution saline a débuté après l'induction de l'anesthésie et a continué jusqu'à la fin de l'intervention à une dose fixe de 0,5 µg·kg−1·h−1. Le critère d'évaluation principal était l'incidence du delirium jusqu'à la fin du 3e jour postopératoire. La survenue de l'agitation au réveil et du delirium postopératoire a été mesurée avec, respectivement, l'échelle d'agitation sous sédation de Riker et la méthode d'évaluation de la confusion. Les critères d'évaluation secondaires étaient les taux sériques de cytokines et de catécholamines. RéSULTATS: La survenue d'une agitation au réveil a été moins fréquente dans le groupe DEX-Sévo que dans le groupe Sévo (respectivement, 13 % contre 35 %; risque relatif, 0,38; intervalle de confiance [IC] à 95 % : 0,18 à 0,79; P = 0,011), mais l'incidence du delirium après congé de la salle de réveil n'a pas été différente entre les groupes (DEX-Sévo 25 % contre Sévo 25 %). Les taux de cytokines pro- et anti-inflammatoires ont tous deux été plus bas dans le groupe DEX-Sévo que dans le groupe Sévo. Néanmoins, les ratios d'interleukines (IL) IL-6/IL-10 (différence entre médianes, 5,8; IC à 95 %, 1,8 à 10,0; P = 0,012) et IL-8/IL-10 (différence des médianes, 0,8; IC à 95 %, 0,2 à 1,3; P = 0,007) ont été plus élevés dans le groupe DEX-Sévo que dans le groupe Sévo indiquant un équilibre des cytokines pro-inflammatoires dans le groupe DEX-Sévo. Les taux de norépinéphrine et d'épinéphrine ont été inférieurs dans le groupe DEX-Sévo que dans le groupe Sévo (P < 0,001 pour les deux). CONCLUSIONS: La dexmédétomidine peropératoire a réduit la survenue de l'agitation au réveil, mais pas du delirium postopératoire chez des patients subissant une chirurgie thoracique. La dexmédétomidine a semblé interférer sur la survenue de l'agitation par le biais des catécholamines, mais pas par un effet anti-inflammatoire. Enregistrement de l'essai clinique Service d'information sur la recherche clinique (KCT 0001877); enregistré le 7 avril 2016.

Stroke Volume Variation and Pulse Pressure Variation Are Not Useful for Predicting Fluid Responsiveness in Thoracic Surgery.

BACKGROUND: Stroke volume variation (SVV) and pulse pressure variation (PPV) are used as indicators of fluid responsiveness, but little is known about the usefulness of these dynamic preload indicators in thoracic surgery, which involves an open thoracic cavity and 1-lung ventilation (OLV). Therefore, we investigated whether SVV and PPV could predict fluid responsiveness, and whether the thresholds of these parameters should be adjusted for thoracic surgery. METHODS: This was a prospective, controlled study conducted in a tertiary care center. Eighty patients scheduled for an elective lobectomy requiring OLV were included (n = 40, video-assisted thoracoscopic surgery (VATS); n = 40, open thoracotomy). Twenty minutes after opening the thoracic cavity, 7 mL/kg hydroxyethyl starch was administered for 30 minutes. Various hemodynamic parameters were measured before and after fluid challenge. RESULTS: Among the 80 patients enrolled in this study, 37% were fluid responders (increase in stroke volume index ≥10%). SVV before fluid challenge was not different between nonresponders and responders (mean ± SD: 7.1 ± 2.7% vs 7.4 ± 2.6%, P = .68). This finding was true regardless of whether the surgery involved open thoracotomy or VATS. PPV before fluid challenge showed the difference between nonresponders and responders (mean ± SD: 6.9 ± 3.0% vs 8.4 ± 3.2%; P = .045); however, the sensitivity and specificity of the threshold value (PPV = 7%) were low (58% and 62%, respectively) and the area under the receiver operating characteristics curve was only 0.63 (95% confidence interval, 0.52-0.74; P = .041). CONCLUSIONS: Dynamic preload indicators are not useful for predicting fluid responsiveness in VATS or open thoracic surgery.

The Risk of Acute Kidney Injury from Fluid Restriction and Hydroxyethyl Starch in Thoracic Surgery.

BACKGROUND: Fluid is restricted in thoracic surgery to reduce acute lung injury, and hydroxyethyl starches (HES) are often administered to reduce fluid amount. This strategy may contribute to the development of acute kidney injury (AKI). We evaluated the incidence, risk factors, and prognosis of AKI in thoracic surgery. We especially focused on whether fluid restriction/HES administration increased AKI. METHODS: This is a retrospective study of patients undergoing thoracic surgery in a tertiary care academic center. Postoperative AKI was diagnosed within 72 hours after surgery based on the Acute Kidney Injury Network criteria. Demographic, intraoperative, and postoperative data were compared between non-AKI and AKI groups. Logistic regression was used to model the association between risk factors and AKI. RESULTS: Final analysis included 1442 patients. Of these, 74 patients developed AKI (5.1%). Crystalloid restriction (≤3 mL·kg·h) was unrelated to AKI, regardless of preoperative renal functions (odds ratio [OR], 0.5; 95% confidence interval [CI] 0.2-1.4). AKI occurred more often when HES were administered to the patients with decreased renal function (OR, 7.6; 95% CI, 1.5-58.1) or having >2 risk factors with normal renal function (OR, 7.2; 95% CI, 3.6-14.1). Multivariate analysis revealed several risk factors: angiotensin-converting enzyme inhibitor/angiotensin receptor blockers, open thoracotomy, pneumonectomy/esophagectomy, diabetes mellitus, cerebrovascular disease, low albumin level, and decreased renal function. CONCLUSIONS: Fluid restriction neither increased nor was a risk factor for AKI. HES should be administered with caution in high-risk patients undergoing thoracic surgery.

Tracheal Intubation with a McGrath® Series 5 Video Laryngoscope by Novice Personnel in a Cervical-immobilized Manikin.

BACKGROUND: Prehospital tracheal intubation may be performed by novice intubators in cervical immobilized patients. However, most indirect laryngoscopes require special training. The McGrath® Series 5 video laryngoscope is similar to the Macintosh laryngoscope in shape and usage, yet still confers the advantages of having indirect laryngoscopes. OBJECTIVE: This study compared tracheal intubation by novice users, using the McGrath® Series 5 video laryngoscope vs. the Macintosh laryngoscope in a cervical immobilized manikin. METHODS: Thirty-eight nurses intubated the trachea of a manikin using a McGrath® Series 5 video laryngoscope and a Macintosh laryngoscope, in random order. Then they repeated the procedure in a manikin with a cervical collar. Success rate, time to success, number of intubation attempts, dental clicks, and difficulty score were compared between the two laryngoscopes. RESULTS: First-attempt success rate was higher for the McGrath® Series 5 compared to the Macintosh laryngoscope in cervical immobilizations (84.2% vs. 47.7%, respectively; p = 0.019). However, overall intubation success rate with and without the cervical collar was no different. Tracheal intubation using the McGrath® Series 5 was faster than the Macintosh laryngoscope regardless of the presence of a cervical collar. McGrath® Series 5 required fewer trials, had fewer dental clicks, and was easier to use than the Macintosh laryngoscope. CONCLUSIONS: McGrath® Series 5 video laryngoscope may be better than a standard Macintosh laryngoscope for novice intubators intubating the trachea in cervical immobilization, due to the higher first-attempt success rate, faster intubation time, fewer dental clicks, lower number of intubation attempts, and overall ease of use.

Influence of carbon dioxide insufflation of the neck on intraocular pressure during robot-assisted endoscopic thyroidectomy: a comparison with open thyroidectomy.

BACKGROUND: Increased intraocular pressure (IOP) during surgery can result in serious ophthalmic complications. We hypothesized that carbon dioxide (CO2) insufflation of the neck during endoscopic thyroidectomy would constrict the jugular veins mechanically, causing elevated venous pressure and thus elevated IOP. We compared IOP changes at each step of open thyroidectomy (OT) versus robot-assisted endoscopic thyroidectomy (RET) METHODS: Perioperatively, IOP was measured at six time points in patients undergoing OT (n = 18) or RET with CO2 insufflation (n = 19). Anesthesia, ventilatory strategy, intravenous infusions, and surgical positioning were standardized RESULTS: In both groups, induction of anesthesia reduced IOP, but surgical positioning with the neck in extension had no effect on IOP. In the OT group, IOP remained unchanged during anesthesia. In the RET group, CO2 insufflation significantly increased IOP to an average of 3.6 ± 3.0 mmHg higher than the previous measurement (P < 0.001), and this IOP increase persisted immediately before gas deflation. These elevated IOP values during CO2 insufflation in the RET group were significantly higher than those at corresponding time points in the OT group. However, these elevated IOP values were similar to the pre-anesthetic baseline IOP CONCLUSION: CO2 insufflation of the neck at pressure of 6 mmHg increased the IOP significantly compared with open thyroidectomy. However, this increase in IOP could be balanced by an anesthetic-induced IOP-lowering effect, thereby having no clinical significance in patients with normal IOP undergoing robot-assisted endoscopic thyroidectomy.

Reactive oxygen species by isoflurane mediates inhibition of nuclear factor κB activation in lipopolysaccharide-induced acute inflammation of the lung.

BACKGROUND: Although anesthetic-induced inhibition of lipopolysaccharide (LPS)-induced lung injury has been recognized, the underlying mechanism is obscure. Some studies suggest that reactive oxygen species (ROS) by isoflurane play a crucial role for anesthetic-induced protective effects on the brain or the heart; however, it still remains controversial. In this study, we examined the role of isoflurane-derived ROS in isoflurane-induced inhibition of lung injury and nuclear factor κB (NFκB) activation in LPS-challenged rat lungs. METHODS: Male Sprague-Dawley rats were subjected to inhalation of 1.0 minimum alveolar concentration of isoflurane for 60 minutes, and intratracheal LPS 0.1 mg was administered 60 minutes later. In some cases, ROS scavenger, 2-mercaptopropinyl glycine or N-acetylcysteine was given 30 minutes before isoflurane. ROS generation was measured by fluorometer before LPS challenge and 4 hours after. Isoflurane's preconditioning effect was assessed by histologic examination, protein content, neutrophil recruitment, and determination of tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, and IL-6 levels in bronchoalveolar lavage fluid and lung tissue. Western blotting measured phosphorylation of inhibitory κB α (ser 32/36), NFκB p65, and inducible nitric oxide synthase (iNOS). TNF-α and IL-6 mRNA expression and immunofluorescence staining for iNOS were also assessed. RESULTS: Isoflurane preconditioning reduced inflammatory lung injury and TNF-α, IL-1ß, and IL-6 release in the lung. Isoflurane upregulated ROS generation before LPS but inhibited a ROS burst after LPS challenge. ROS scavenger administration before isoflurane abolished the isoflurane preconditioning effect as well as isoflurane-induced inhibition of phosphorylation of inhibitory κBα, NFκB p65, iNOS activation, and mRNA expression of TNF-α and IL-6 in acute LPS-challenged lungs. CONCLUSIONS: This study suggests a crucial role of upregulated ROS generation by isoflurane for modification of inflammatory pathways by isoflurane preconditioning in acute inflammation of the lung.

Chest anteroposterior diameter affects difficulty of laryngoscopy for non-morbidly obese patients.

PURPOSE: This prospective, observational study was performed to examine the hypothesis that if conventional 7-cm head elevation is applied, laryngoscopy is more difficult for patients with anteroposterior chest diameter (chest AP diameter) outside the average range (≥17.7 or ≤14.7 cm). METHODS: Chest AP diameter at the sternal notch were measured preoperatively. All patients were placed on a surgical bed with an incompressible 7-cm pillow. During laryngoscopy, the laryngeal view was graded by use of the Cormack-Lehane classification. Difficult visualization of the larynx (DVL) was defined as a grade 3 or 4 view. RESULTS: DVL was observed for 49 patients (18.2 %). Differences between measured chest AP diameter for each patient and the calculated median value were used for statistical analysis. In univariate analysis, the difference between chest AP diameter and the median value was significantly related to DVL. Logistic regression analysis confirmed that the difference between chest AP diameter and the median value was an independent predictor of DVL (odds ratio, 3.900; 95 % confidence interval, 2.371-6.415; p < 0.001). Receiver operating characteristic curve analysis showed that this test with a test threshold of 1.5 cm had reasonable diagnostic accuracy (area under the curve of 0.748). CONCLUSION: When using a standard pillow size of 7 cm, chest AP diameter above or below the average range (≥17.7 or ≤14.7 cm) was a strong predictor of DVL for apparently normal-sized patients. In such cases, modification of pillow height should be considered.

The arousal effect of sugammadex reversal of neuromuscular blockade differs with anesthetic depth in propofol-remifentanil anesthesia: a randomized controlled trial.

Sugammadex reverses neuromuscular blockade by encapsulating steroidal neuromuscular blockers; therefore, it does not pharmacologically affect sedation levels. However, some clinicians avoid using it because of sudden unwanted acting out or patient arousal. Previous studies suggested sugammadex-induced awakening, but frontal muscle contraction after sugammadex administration compromised reliability of results obtained from EEG-based anesthesia depth monitoring tools like bispectral index (BIS). We hypothesized that sugammadex would affect patients' arousal depending on their baseline levels of sedation. We evaluated arousal signs after sugammadex administration with BIS between 25 - 35 and 45 - 55 under steady-state propofol-remifentanil anesthesia at the end of a surgery (n = 33 in each group). After sugammadex administration, twelve patients with a BIS of 45 - 55 showed clinical signs of awakening but none with a BIS of 25 - 35 (36.4% vs. 0%, P = 0.001). The distribution of the modified observer's assessment of alertness/sedation scale scores was also significantly different between the two groups (P < 0.001). Changes in the BIS were significantly greater in the BIS 45 - 55 than in the 25 - 35 group (median difference, 7; 95% CI 2 - 19, P = 0.002). Arousal after sugammadex was affected by patient sedation levels, and clinical signs of awakening appeared only in those with BIS 45 - 55. Unwanted arousal of the patient should be considered when using sugammadex under shallow anesthesia.Clinical trial registry number: Clinical Trial Registry of Korea ( https://cris.nih.go.kr ; Principal investigator: Jieae Kim; Registration number: KCT0006248; Date of first registration: 11/06/2021).

Comparison of Early and Late Surgeries after Coronary Stent Implantation in Patients with Normal Preoperative Troponin Level: A Retrospective Study.

Current guidelines recommend delaying noncardiac surgery for 6 months after drug eluting stent implantation. However, this recommendation is largely based on limited evidence and various event definitions. Whether early surgery within 6 months of coronary stent implantation increases myocardial injury in patients with normal preoperative high-sensitivity cardiac troponin I (hs-cTnI) has not yet been investigated. This retrospective study assessed patients who received coronary stent implantation and underwent noncardiac surgery (vascular, abdominal, or thoracic) between 2010 and 2017 with normal preoperative hs-cTnI (n = 186). Patients were divided into early (within 6 months of PCI) and late (after 6 months of PCI) groups. The primary endpoint was the incidence of myocardial injury as diagnosed by hs-cTnI within 3 days post-operation. The secondary outcomes were myocardial infarction, stent thrombosis, emergent coronary revascularization, major bleeding (bleeding requiring transfusion or intracranial bleeding), stroke, renal failure, heart failure, or death within 30 days post-operation. Inverse probability treatment weighting (IPTW) was carried out to adjust for the intergroup baseline differences. Myocardial injury occurred in 28.6% (8/28) and 27.8% (44/158) of the early and late groups, respectively, with no difference between groups (odds ratio [OR] 1.067, 95% confidence interval [CI] 0.404, 2.482; p = 0.886). Secondary outcomes did not differ between the groups. IPTW analysis also showed no differences in myocardial injury and secondary outcomes between the groups. In conclusion, early surgery within 6 months after coronary stent implantation did not increase the incidence of myocardial injury in patients with normal preoperative hs-cTnI.

Comparison of pulmonary morbidity using sevoflurane or propofol-remifentanil anesthesia in an Ivor Lewis operation.

OBJECTIVE: An inhalation anesthetic-induced attenuation effect on the inflammatory reaction during one-lung ventilation (OLV) has been reported. Pulmonary inflammation is a substantive prognostic factor for Ivor Lewis operations. Blood inflammatory parameters and postoperative pulmonary complications between sevoflurane and propofol-remifentanil anesthesia in patients undergoing Ivor Lewis operations were compared. DESIGN: A prospective, randomized study. SETTING: A medical university. PARTICIPANTS: Forty-eight patients undergoing Ivor Lewis operation allocated randomly into 2 groups. INTERVENTIONS: Patients received sevoflurane or total intravenous anesthesia using propofol and remifentanil (n = 24 per group). MEASUREMENTS AND MAIN RESULTS: Blood interleukin-6 (IL-6), malondialdehyde (MDA), oxygenation, abnormalities on a chest radiograph (CXR), extubation, intensive care unit (ICU) stay, length of hospitalization, and postoperative complications were compared between the 2 anesthetic techniques. The level of IL-6 at the end of surgery was lower for sevoflurane (69.5 [35.9-121.0] pg/mL) than propofol-remifentanil (128.2 [92.8-163.8] pg/mL, p = 0.03), but this difference was not maintained 24 hours after surgery. Frequencies of abnormalities measured by a CXR, PaO(2)/F(I)O(2)<300, and PaCO(2) <50 mmHg until discharge, the postoperative highest C-reactive protein level, white blood cells, and MDA did not differ between the 2 anesthetics. No differences in the extubation time, ICU stay, discharge day, or the incidence of hospital complications between sevoflurane and propofol-remifentanil anesthesia techniques were observed. CONCLUSIONS: Sevoflurane anesthesia attenuated an increase in blood IL-6 at the end of surgery but did not provide any advantages over propofol remifentanil in terms of postoperative pulmonary complications in Ivor Lewis operations.

The impact of pulmonary function tests on early postoperative complications in open lung resection surgery: an observational cohort study.

We investigated whether pulmonary function tests (PFTs) can predict pulmonary complications and if they are, to find new cutoff values in current open lung resection surgery. In this observational study, patients underwent open lung resection surgery at a tertiary hospital were analyzed (n = 1544). Various PFTs were tested by area under the receiver-operating characteristic curve (AUCROC) to predict pulmonary complications until 30 days postoperatively. In results, PFTs were generally not effective to predict pulmonary complications (AUCROC: 0.58-0.66). Therefore, we could not determine new cutoff values, and used previously reported cutoffs for post-hoc analysis [predicted postoperative forced expiratory volume in one second (ppoFEV1) < 40%, predicted postoperative diffusing capacity for carbon monoxide (ppoDLCO) < 40%]. In multivariable analysis, old age, male sex, current smoker, intraoperative transfusion and use of inotropes were independent risk factors for pulmonary complications (model 1: AUCROC 0.737). Addition of ppoFEV1 or ppoDLCO < 40% to model 1 did not significantly increase predictive capability (model 2: AUCROC 0.751, P = 0.065). In propensity score-matched subgroups, patients with ppoFEV1 or ppoDLCO < 40% showed higher rates of pulmonary complications [13% (21/160) vs. 24% (38/160), P = 0.014], but no difference in in-hospital mortality [3% (8/241) vs. 6% (14/241), P = 0.210] or mean survival duration [61 (95% CI 57-66) vs. 65 (95% CI 60-70) months, P = 0.830] compared to patients with both > 40%. In conclusion, PFTs themselves were not effective predictors of pulmonary complications. Decision to proceed with surgical resection of lung cancer should be made on an individual basis considering other risk factors and the patient's goals.

Preemptive Administration of Albumin during Pancreatectomy Does Not Reduce Postoperative Complications: A Prospective Randomized Controlled Trial.

Despite the empirical use of human albumin during pancreatectomy to replace intraoperative volume loss while preventing fluid overload and edema, its impact on postoperative outcomes remains unclear. In addition, most previous studies have focused on the effects of therapeutic albumin usage. Here, we investigated whether preemptive administration of human albumin to prevent edema during pancreatectomy could reduce the incidence of moderate postoperative complications. Adult patients undergoing pancreatectomy were assigned to either the albumin group (n = 100) or the control group (n = 100). Regardless of the preoperative albumin level, 200 mL of 20% albumin was administered to the albumin group after induction of anesthesia. The primary outcome was the incidence of moderate postoperative complications as defined by a Clavien-Dindo classification grade ≥ 2 at discharge. Intraoperative net-fluid balance, a known risk factor of postoperative complication after pancreatectomy, was lower in the albumin group than in the control group (p = 0.030), but the incidence of moderate postoperative complications was not different between the albumin and control groups (47/100 vs. 38/100, respectively; risk ratio: 1.24, 95% CI: 0.89 to 1.71; p = 0.198). Therefore, preemptive administration of human albumin to prevent fluid overload and edema during pancreatectomy is not recommended because of its lack of apparent benefit in improving postoperative outcomes.

The Lack of Analgesic Efficacy of Nefopam after Video-Assisted Thoracoscopic Surgery for Lung Cancer: A Randomized, Single-Blinded, Controlled Trial.

Nefopam is a centrally acting non-opioid analgesic, and its efficacy in multimodal analgesia has been reported. This study aimed to assess the analgesic efficacy of intraoperative nefopam on postoperative pain after video-assisted thoracoscopic surgery (VATS) for lung cancer. Participants were randomly assigned to either the nefopam or the control group. The nefopam group received 20 mg of nefopam after induction and 15 min before the end of surgery. The control group received saline. The primary outcome was cumulative opioid consumption during the 6 h postoperatively. Pain intensities, the time to first request for rescue analgesia, adverse events during the 72 h postoperatively, and the incidence of chronic pain 3 months after surgery were evaluated. Ninety-nine patients were included in the analysis. Total opioid consumption during the 6 h postoperatively was comparable between the groups (nefopam group [n = 50] vs. control group [n = 49], 19.8 [13.5-25.3] mg vs. 20.3 [13.9-27.0] mg; median difference: -1.55, 95% CI: -6.64 to 3.69; p = 0.356). Pain intensity during the 72 h postoperatively and the incidence of chronic pain 3 months after surgery did not differ between the groups. Intraoperative nefopam did not decrease acute postoperative opioid consumption or pain intensity, nor did it reduce the incidence of chronic pain after VATS.