Hypotension prediction index for prevention of intraoperative hypotension in patients undergoing general anesthesia: a randomized controlled trial.

BACKGROUND: Intraoperative hypotension is a common side effect of general anesthesia. Here we examined whether the Hypotension Prediction Index (HPI), a novel warning system, reduces the severity and duration of intraoperative hypotension during general anesthesia. METHODS: This randomized controlled trial was conducted in a tertiary referral hospital. We enrolled patients undergoing general anesthesia with invasive arterial monitoring. Patients were randomized 1:1 either to receive hemodynamic management with HPI guidance (intervention) or standard of care (control) treatment. Intraoperative hypotension treatment was initiated at HPI > 85 (intervention) or mean arterial pressure (MAP) < 65 mmHg (control). The primary outcome was hypotension severity, defined as a time-weighted average (TWA) MAP < 65 mmHg. Secondary outcomes were TWA MAP < 60 and < 55 mmHg. RESULTS: Of the 60 patients who completed the study, 30 were in the intervention group and 30 in the control group. The patients' median age was 62 years, and 48 of them were male. The median duration of surgery was 490 min. The median MAP before surgery presented no significant difference between the two groups. The intervention group showed significantly lower median TWA MAP < 65 mmHg than the control group (0.02 [0.003, 0.08] vs. 0.37 [0.20, 0.58], P < 0.001). Findings were similar for TWA MAP < 60 mmHg and < 55 mmHg. The median MAP during surgery was significantly higher in the intervention group than that in the control group (87.54 mmHg vs. 77.92 mmHg, P < 0.001). CONCLUSIONS: HPI guidance appears to be effective in preventing intraoperative hypotension during general anesthesia. Further investigation is needed to assess the impact of HPI on patient outcomes. TRIAL REGISTRATION: ClinicalTrials.gov (NCT04966364); 202105065RINA; Date of registration: July 19, 2021; The recruitment date of the first patient: July 22, 2021.

Validity of the I­FEED classification in assessing postoperative gastrointestinal impairment in patients undergoing elective lumbar spinal surgery with general anesthesia: a prospective observational study.

BACKGROUND: The I-FEED classification, scored 0-8, was reported to accurately describe the clinical manifestations of gastrointestinal impairment after colorectal surgery. Therefore, it is interesting to determine whether the I-FEED scoring system is also applicable to patients undergoing lumbar spine surgery. METHODS: Adult patients undergoing elective lumbar spine surgery were enrolled, and the I-FEED score was measured for 4 days after surgery. The I-FEED scoring system incorporates five elements: intake (score: 0, 1, 3), feeling nauseated (score: 0, 1, 3), emesis (score: 0, 1, 3), results of physical exam (score: 0, 1, 3), and duration of symptoms (score: 0, 1, 2). Daily I-FEED scores were summed, and the highest overall score is used to categorize patients into one of three categories: normal (0-2 points), postoperative gastrointestinal intolerance (POGI; 3-5 points), and postoperative gastrointestinal dysfunction (POGD; 6 + points). The construct validity hypothesis testing determines whether the I-FEED category is consistent with objective clinical findings relevant to gastrointestinal impairment, namely, the longer length of hospital stay (LOS), higher inhospital medical cost, more postoperative gastrointestinal medical treatment, and more postoperative non-gastrointestinal complications. RESULTS: A total of 156 patients were enrolled, and 25.0% of patients were categorized as normal, 49.4% POGI, and 25.6% POGD. Patients with higher I-FEED scores agreed with the four validity hypotheses. Patients with POGD had a significantly longer length of hospital stay (1 day longer median stay; p = 0.049) and more inhospital medical costs (approximately 500 Taiwanese dollars; p = 0.037), and more patients with POGD required rectal laxatives (10.3% vs. 32.5% vs. 32.5%; p = 0.026). In addition, more patients with POGD had non-gastrointestinal complications (5.1% vs. 11.7% vs. 30.0%; p = 0.034). CONCLUSION: This study contributes preliminary validity evidence for the I-FEED score as a measure for postoperative gastrointestinal impairment after elective lumbar spine surgery.

Relationship Between Subjective Questionnaires and Videofluoroscopy of Dysphagia Evaluation: A Systematic Review and Meta-Analysis.

BACKGROUND: Early detection of dysphagia is important for preventing aspiration pneumonia. Although videofluoroscopy is currently the primary diagnostic tool for dysphagia, access to this tool may be limited because of radiation exposure risk, high cost, and other factors. PURPOSE: In this study, a meta-analysis was used to determine the strength of the correlation between dysphagia detection outcomes obtained using subjective questionnaires and videofluoroscopy. METHODS: The PubMed and Embase databases were searched for original articles up to December 2022. Studies published in English that used cross-sectional designs to assess the correlation between subjective questionnaires and videofluoroscopy were considered eligible for inclusion. The search terms used included "dysphagia," "questionnaire," and "videofluoroscopy." Two reviewers critically appraised and extracted the correlation coefficient r values. In addition, a random-effects meta-analysis was conducted. The Q statistic was used to assess the heterogeneity among the included studies. Publication bias was checked using the funnel plot and Egger's tests. Multilevel analysis was used to determine sensitivity to consider within-study correlations. In addition, subgroup analyses were conducted based on type of questionnaire, head and neck cancer, and English-speaking regions. RESULTS: The meta-analysis included five studies and 856 patients using the Eating Assessment Tool-10 and one study and 27 patients using the Sydney Swallow Questionnaire. The results of the random-effects meta-analysis showed a moderate relationship between the subjective questionnaires and videofluoroscopy ( r = .35, 95% CI [0.20, 0.48]). Similar results were also obtained using multilevel analysis ( r = .34, 95% CI [0.25, 0.42]). No publication bias was found for any of the studies ( p = .88). In the subgroup analyses, a moderate relationship between Eating Assessment Tool-10 and videofluoroscopy ( r = .31, 95% CI [0.19, 0.42]) and an ultrahigh relationship between Sydney Swallow Questionnaire and video-fluoroscopy ( r = .74, 95% CI [0.50, 0.87]) were found. Furthermore, moderate associations were observed within each head and neck cancer and English-speaking regions subgroup. However, no significant differences were found between these two subgroups. CONCLUSIONS: These results indicate the subjective questionnaires considered in this study share a moderate relationship with videofluoroscopy. Subjective questionnaires may be used as an auxiliary tool by nurses and homecare givers for the early assessment of dysphagia risk in patients.

Incidence and risk factors of postoperative pulmonary complications after oral cancer surgery with free flap reconstruction: A single center study.

BACKGROUND: Postoperative pulmonary complications (PPCs) increase the risk of morbidity and mortality in patients who underwent oral cancer surgery with free flap reconstruction. The association between PPC and preoperative risk factors has been investigated; however, reports on intraoperative factors are limited. Therefore, we investigated PPC incidence and its associated preoperative and intraoperative risk factors in these patients. METHODS: We retrospectively analyzed medical records of patients who underwent free flap reconstruction between 2009 and 2019. PPC was defined as presence of atelectasis, pneumonia, and respiratory failure based on radiological confirmation and clinical symptoms during hospitalization. Mortality, hospital stay, preoperative factors (including age and tumor stages), American Society of Anesthesiologists (ASA) classification, and intraoperative factors (including intraoperative fluids and medications) were recorded. RESULTS: PPC incidence among the 993 patients included in this study was 25.8% (256 patients). Six patients with PPCs died; death was not observed among patients without PPCs (p < 0.001). Patients with PPCs had longer hospitalization than those without PPCs (30.3 vs 23.3 days; p < 0.001). Tumor stage (stage I: reference; stage II [OR]: 3.3, p = 0.019; stage III: 4.4, p = 0.002; stage IV: 4.8, p = 0.002), age (OR: 1.0; p < 0.001), and ASA grade >2 (OR: 1.4; p = 0.020) were independent risk factors of PPC; using labetalol was a borderline significant factor (OR: 1.4; p = 0.050). CONCLUSION: The PPC incidence was 25.8% in patients undergoing oral cancer surgery with free flap reconstruction. Tumor stage, age, and ASA >2 were risk factors of developing PPC.

Detecting Volemic, Cardiac, and Autonomic Responses From Hypervolemia to Normovolemia via Non-Invasive ClearSight Hemodynamic Monitoring During Hemodialysis: An Observational Investigation.

Background: Unstable hemodynamics are not uncommon during hemodialysis (HD), which involves a rapid volume depletion, taking the patient from hypervolemia toward euvolemia. Since uremic patients commonly have cardiovascular comorbidities, hemodynamic changes during HD may reflect interactions among the volemic, cardiac, and autonomic responses to gradual volume depletion during ultrafiltration. Accurate identification of inappropriate responses helps with precisely managing intradialytic hypotension. Recently, the non-invasive ClearSight was reported to be able to detect causes of intraoperative hypotension. In this prospective observational study, we aimed to determine whether ClearSight could be used to detect patterns in stroke volemic, cardiac, and vasoreactive responses during HD. Methods: ClearSight was used to monitor chronic stable patients receiving maintenance HD. Data of mean arterial blood pressure (MAP), heart rate (HR), stroke volume index (SVI), cardiac index (CI), and calculated systemic vascular resistance index (SVRI) were obtained and analyzed to examine patterns in volemic, cardiac, and vasoreactive changes from T0 (before HD) until T8 in 30-min intervals (total 4 h). Results: A total of 56 patients with a mean age of 60.5 years were recruited, of which 40 of them were men. The average ultrafiltration volume at T8 was 2.1 ± 0.8 L. The changes in MAP and HR from T0 to T8 were non-significant. SVI at T7 was significantly lower than that at T1, T2, and T3. CI at T4 to T8 was significantly lower than that at T0. SVRI was significantly higher at T3 to T8 than at T0. Pearson's correlation coefficients between SVI and CI and between SVRI and MAP were positive at all time points. The correlation coefficients between SVRI and SVI and between CI and SVRI were significant and negative for all time points. Conclusion: ClearSight was able to detect patterns in hypervolemia during HD and was well tolerated for 4 h. CI decreased significantly after T4, with slightly decreased SVI. Ultrafiltration volume was not correlated with changes in SVI or CI. The vascular tone increased significantly, and this counteracted the reduced cardiac output after T4. With simultaneous monitoring on SVI, CI, and SVRI during HD, therefore, hypotension could be detected and managed by reducing the filtration rate or administering inotrope or vasopressors. Trial Registration: clinicaltrials.gov, ID: NCT03901794.

Applying High-Resolution Impedance Manometry for Detecting Swallowing Change in Anterior Cervical Spine Surgery Patients.

Background: Objectively detecting perioperative swallowing changes is essential for differentiating the reporting of subjective trouble sensations in patients undergoing anterior cervical spine surgery (ACSS). Swallowing indicates the transmission of fluid boluses from the pharynx (velopharynx, oropharynx, and hypopharynx) through the upper esophageal sphincter (UES). Abnormal swallowing can reveal fluid accumulation at the pharynx, which increased the aspiration risk. However, objective evidence is limited. High-resolution impedance manometry (HRIM) was applied for an objective swallowing evaluation for a more detailed analysis. We aimed to elucidate whether HRIM can be used to detect perioperative swallowing changes in patients undergoing ACSS. Methods: Fourteen patients undergoing elective ACSS underwent HRIM with the Dysphagia Short Questionnaire (DSQ, score: 0-18) preoperatively (PreOP), on postoperative at day 1 (POD1), and postoperative at day seven (POD7). We calculated hypopharyngeal and UES variables, including hypopharyngeal mean peak pressure (PeakP) and UES peak pressure, representing their contractility (normal range of PeakP, 69-280 mmHg; peak pressure, 149-548 mmHg). The velopharynx-to-tongue base contractile (VTI) was also calculated (normal range, 300-700 mmHg.s.cm), indicating contractility. The swallowing risk index (SRI) from HRIM combined with four hypopharyngeal parameters, including PeakP, represents the global swallowing function (normal range, 0-11). A higher SRI value indicated higher aspiration. Results: SRI was significantly higher on POD1 (10.88 ± 5.69) than PreOP (6.06 ± 3.71) and POD7 (8.99 ± 4.64). In all patients, PeakP was significantly lower on POD1 (61.8 ± 18.0 mmHg) than PreOP (84.9 ±34.7 mmHg) and on POD7 (75.3 ± 23.4 mmHg). The UES peak pressure was significantly lower on POD1 (80.4 ± 30.0 mmHg) than PreOP (112.9 ± 49.3 mmHg) and on POD7 (105.6 ± 59.1 mmHg). Other variables, including VTI, did not change significantly among the three time points. DSQ scores were 1.36, 3.43, and 2.36 at PreOP, POD1, and POD7 respectively. Conclusions: With similar trends in DSQ and SRI, swallowing was significantly decreased on POD1 because of decreased hypopharyngeal and UES contractility but recovered to the preoperative state on POD7 after ACSS. Applying HRIM is superior to DSQ in detecting mechanisms and monitoring the recovery from swallowing dysfunction. Clinical Trial Registration: The study was registered at ClinicalTrials.gov (NCT03891940).

Comparison of the efficacy of supraglottic airway devices in low-risk adult patients: a network meta-analysis and systematic review.

Numerous supraglottic airway device (SADs) have been designed for adults; however, their relative efficacy, indicated by parameters such as adequacy of sealing, ease of application, and postinsertion complications, remains unclear. We conducted a systematic review and network meta-analysis to evaluate the efficacy of various SADs. We searched electronic databases for randomized controlled trials comparing at least two types of SADs published before December 2019. The primary outcomes were oropharyngeal leak pressure (OLP), risk of first-attempt insertion failure, and postoperative sore throat rate (POST). We included 108 studies (n = 10,645) comparing 17 types of SAD. The Proseal laryngeal mask airway (LMA), the I-gel supraglottic airway, the Supreme LMA, the Streamlined Liner of the Pharynx Airway, the SoftSeal, the Cobra Perilaryngeal Airway, the Air-Q, the Laryngeal Tube, the Laryngeal Tube Suction II, the Laryngeal Tube Suction Disposable, AuraGain, and Protector had significantly higher OLP (mean difference ranging from 3.98 to 9.18 cmH2O) compared with that of a classic LMA (C-LMA). The Protector exhibited the highest OLP and was ranked first. All SADs had a similar likelihood of first-attempt insertion failure and POST compared with the C-LMA. Our findings indicate that the Protector may be the best SAD because it has the highest OLP.Systematic review registration PROSPERO: CRD42017065273.

Detecting Oropharyngeal and Esophageal Emptying by Submental Ultrasonography and High-Resolution Impedance Manometry: Intubated vs. Non-Intubated Video-Assisted Thoracoscopic Surgery.

Postoperative swallowing, affected by general anesthesia and intubation, plays an important part in airway and oral intake safety regarding effective oropharyngeal and esophageal emptying. However, objective evidence is limited. This study aimed to determine the time required from emergence to effective oropharyngeal and esophageal emptying in patients undergoing non-intubated (N) or tracheal-intubated (I) video-assisted thoracoscopic surgery (VATS). Hyoid bone displacement (HBD) by submental ultrasonography and high-resolution impedance manometry (HRIM) measurements were used to assess oropharyngeal and esophageal emptying. HRIM was performed every 10 min after emergence, up to 10 times. The primary outcome was to determine whether intubation affects the time required from effective oropharyngeal to esophageal emptying. The secondary outcome was to verify if HBD is comparable to preoperative data indicating effective oropharyngeal emptying. Thirty-two patients suitable for non-intubated VATS were recruited. Our results showed that comparable HBDs were achieved in all patients after emergence. Effective esophageal emptying was achieved at the first HRIM measurement in 11 N group patients and 2 I group patients (p = 0.002) and was achieved in all N (100%) and 13 I group patients (81%) within 100 min (p = 0.23). HBD and HRIM are warranted for detecting postoperative oropharyngeal and esophageal emptying.

Perioperative gastroesophageal regurgitation in patients with elevated abdominal pressure with nasogastric tubes? A simulation model based on esophageal multichannel intraluminal impedance and pH monitoring.

Increased abdominal pressure is common in obese patients and predisposes them to gastroesophageal regurgitation (GER). To drain GER and prevent aspiration, nasogastric (NG) tubes are frequently inserted in obese patients undergoing general anesthesia. However, whether gastric drainage actually decreases the occurrence of GER remains to be elucidated. In this study, increased abdominal pressure was simulated with laparoscopic pneumoperitoneum and Trendelenburg (LPT) positioning, while the retained NG tube was replaced by a pre-inserted esophageal multichannel intraluminal and pH (MII-pH) monitoring. Fifteen patients undergoing elective gynecologic laparoscopy were enrolled in this study. Thirteen patients (86%) developed GER while in the LPT position. With the high occurrence of GER, pre-inserted NG tubes under general anesthesia are not likely to be protective in obese patients.

Detecting intraoperative gastric regurgitation by using preattached esophageal multichannel intraluminal impedance and pH monitoring on a solid-state manometry: a case series study.

Adequate barrier pressure (BrP), calculated by subtracting intragastric pressure (IGP) from lower esophageal sphincter pressure (LESP), is believed to prevent gastroesophageal regurgitation (GER). However, the occurrence of intraoperative GER, the height and acidity it reached, have rarely been demonstrated simultaneously along with BrP. In this study, we developed preattached multichannel intraluminal impedance monitoring combined with pH-metry (the gold standard for detecting both height and acidity) on a solid-state manometry to continuously detect intraoperative GER as well as BrP changes. We used this system to record LESP, IGP, and changes in impedance through multichannel sensors and pH in patients receiving elective gynecological laparoscopy with laparoscopic pneumoperitoneum and Trendelenburg (LPT) positioning. Changes in BrP were analyzed at three time points (T1: before LPT; T2: during LPT when LESP reached its peak; and T3: after the offset of LPT). Our results indicated that this preattached experimental setup is feasible for intraoperative applications. GER was not detected in our patients throughout LPT. The mean LESP at T2 (23.22 mmHg) was significantly higher than at T1 (13.23 mmHg), but comparable to that at T3 (18.91 mmHg). The mean IGP (3.24 mmHg) at T2 was significantly higher than at T1 and T3 (- 6.10 and - 2.25 mmHg, respectively). The mean BrP scores were comparable from T1 to T3 (T1: 19.34 mmHg; T2: 19.98 mmHg; T3: 21.16 mmHg). Based on our results, the proposed setup is helpful for intraoperative monitoring and management of patients at high risk of GER.

The Performance of Supraglottic Airway Devices at Different Head and Neck Rotation Angles.

OBJECTIVE: Supraglottic airway devices (SGAs) have advantages in reducing respiration-associated complications. However, limited studies on the influence of head and neck rotation on the risk of air leakage have been conducted. We hypothesize that different head and neck rotation angles will increase the risk of air leakage when using SGAs. METHODS: A prospective, randomized study was conducted with 51 patients in the i-gelTM group and 50 patients in the AuraOnceTM group. The head and neck were subsequently rotated to the following positions: 0 (neutral), 15, 30, 45, and 60 degrees. Airway pressure over 20 cmH2O was defi ned as negative for air leakage. RESULTS: The percentage of air leakage was proportional to the increase in rotational degrees at the various rotation angles. The incidence of patients without air leakage at the largest angle (60 degrees) of head and neck rotation in both groups was approximately 80% (i-gelTM: 82.35%; AuraOnceTM: 79.59%).Conclusion: SGAs presented acceptable performance with increased head and neck rotation angles. CONCLUSION: SGAs presented acceptable performance with increased head and neck rotation angles.

Pharmacogenetic study of pruritus induced by epidural morphine for post cesarean section analgesia.

OBJECTIVE: The mechanism through which neuroaxial morphine causes pruritus has not been elucidated clearly and thoroughly. MATERIALS AND METHODS: a study in 129 female parturients was conducted to investigate the effect of 14 single nucleotide polymorphisms (SNPs) on phenotype (pruritus) induced by neuroaxial (including intrathecal or epidural) morphine for cesarean section. Clinical phenotype, subjective complaints and objective observations were recorded. DNA from blood samples was used to record the SNPs. Eleven SNPs were then analyzed further. RESULTS: no significant association with the presence of phenotype (pruritus) versus genotype was observed (all p-values > 0.05). No significant association with severity of phenotype versus genotype of the 11 SNPs was observed except for unadjusted data for rs2737703. There was no significant difference between severity or incidence of IVPCA morphine-induced nausea and vomiting and genotype (11 SNPs). CONCLUSION: our results showed no association between SNPs of any of the genes studied with neuroaxial morphine inducing pruritus.

I-Gel is a suitable alternative to endotracheal tubes in the laparoscopic pneumoperitoneum and trendelenburg position.

BACKGROUND: The use of supraglottic airway devices (SADs) in surgeries with laparoscopic pneumoperitoneum and Trendelenburg (LPT) positioning is controversial due to concerns about insufficient pulmonary ventilation and aspiration. In this prospective, randomized-controlled trial, we evaluated whether the i-gel, a new second generation SAD, provides an effective alternative to an endotracheal tube (ETT) by comparing respiratory parameters and perioperative respiratory complications in non-obese patients. METHODS: In a randomized controlled trial, forty anesthetized patients with ASA I-II were divided into equally sized i-gel and ETT groups. We evaluated the respiratory parameters in the supine and LPT position in comparison between the two groups. The leak fraction was our primary outcome, which was defined as the leak volume divided by the inspired tidal volume. The leak volume was the difference between the inspired and expired tidal volumes. We also monitored pulmonary aspiration and respiratory complications during the perioperative period. RESULTS: In the LPT position, there were no differences in the leak fraction (median [IQR]) between the i-gel and ETT groups (6.20[3.49] vs 6.38[3.71] %, P = 0.883). In the i-gel group, notably less leakage was observed in the LPT position than in the supine position (median [IQR]: 7.01[3.73] %). This phenomenon was not observed in the ETT group. The rate of postoperative sore throat was also significantly lower in the i-gel group than in the ETT group (3/17 vs 9/11). No vomitus nor any signs associated with aspiration were noted in our patients after extubation in the follow-up prior to discharge. CONCLUSIONS: The i-gel provides a suitable alternative to an ETT for surgeries with LPT positioning in non-obese patients. TRIAL REGISTRATION: Registered at Clinicaltrials.gov NCT02462915 , registered on 1 June 2015.