Effect of Electrical Impedance Tomography-Guided Early Mobilization in Patients After Major Upper Abdominal Surgery: Protocol for a Prospective Cohort Study

Background: Pulmonary complications are common in patients after upper abdominal surgery, resulting in poor clinical outcomes and increased costs of hospitalization. Enhanced Recovery After Surgery Guidelines strongly recommend early mobilization post-operatively; however, the quality of the evidence is poor, and indicators for quantifying the effectiveness of early mobilization are lacking. This study will evaluate the effectiveness of early mobilization in patients undergoing an upper abdominal surgery using electrical impedance tomography (EIT). Specifically, we will use EIT to assess and compare the lung ventilation distribution among various regions of interest (ROI) before and after mobilization in this patient population. Additionally, we will assess the temporal differences in the distribution of ventilation in various ROI during mobilization in an effort to develop personalized activity programs for this patient population.Methods: In this prospective, single-center cohort study, we aim to recruit 50 patients after upper abdominal surgery between July 1, 2021 and June 30, 2022. This study will use EIT to quantify the ventilation distribution among different ROI. On post-operative day 1, the nurses will assist the patient to sit on the chair beside the bed. Patient's heart rate, blood pressure, oxygen saturation, respiratory rate, and ROI 1-4 will be recorded before the mobilization as baseline. These data will be recorded again at 15, 30, 60, 90, and 120 min after mobilization, and the changes in vital signs and ROI 1-4 values at each time point before and after mobilization will be compared.Ethics and Dissemination: The study protocol has been approved by the Institutional Review Board of Liaocheng Cardiac Hospital (2020036). The trial is registered at chictr.org.cn with identifier ChiCTR2100042877, registered on January 31, 2021. The results of the study will be presented at relevant national and international conferences and submitted to international peer-reviewed journals. There are no plans to communicate results specifically to participants. Important protocol modifications, such as changes to eligibility criteria, outcomes, or analyses, will be communicated to all relevant parties (including investigators, Institutional Review Board, trial participants, trial registries, journals, and regulators) as needed via email or in-person communication.

Electrical Impedance Tomography Predicts Weaning Success in Adult Patients With Delayed Upper Abdominal Surgery: A Single-Center Retrospective Study

Objective: To evaluate the predictive value of electrical impedance tomography (EIT) in patients with delayed ventilator withdrawal after upper abdominal surgery.Methods: We retrospectively analyzed data of patients who were ventilated >24 h after upper abdominal surgery between January 2018 and August 2019. The patients were divided into successful (group S) and failed (group F) weaning groups. EIT recordings were obtained at 0, 5, 15, and 30 min of spontaneous breathing trials (SBTs) with SBT at 0 min set as baseline. We assessed the change in delta end-expiratory lung impedance and tidal volume ratio (ΔEELI/VT) from baseline, the change in compliance change percentage variation (|Δ(CW-CL)|) from baseline, the standard deviation of regional ventilation delay index (RVDSD), and global inhomogeneity (GI) using generalized estimation equation analyses. Receiver operating characteristic curve analyses were performed to evaluate the predictive value of parameters indicating weaning success.Results: Among the 32 included patients, ventilation weaning was successful in 23 patients but failed in nine. Generalized estimation equation analysis showed that compared with group F, the ΔEELI/VT was lower, and the GI, RVDSD, and (|Δ(CW-CL)|) were higher in group S. For predicting withdrawal failure, the areas under the curve of the ΔEELI/VT, (|Δ(CW-CL)|), and the RVDSD were 0.819, 0.918, and 0.918, and 0.816, 0.884, and 0.918 at 15 and 30 min during the SBTs, respectively.Conclusion: The electrical impedance tomography may predict the success rate of ventilator weaning in patients with delayed ventilator withdrawal after upper abdominal surgery.

Programmed Intermittent Epidural Bolus versus Continuous Epidural Infusion in Major Upper Abdominal Surgery: A Retrospective Comparative Study

Although recent evidence shows that the programmed intermittent epidural bolus can provide improved analgesia compared to continuous epidural infusion during labor, its usefulness in major upper abdominal surgery remains unclear. We evaluated the effect of programmed intermittent epidural bolus versus continuous epidural infusion on the consumption of postoperative rescue opioids, pain intensity, and consumption of local anesthetic by retrospective analysis of data of patients who underwent major upper abdominal surgery under ultrasound-assisted thoracic epidural analgesia between July 2018 and October 2020. The primary outcome was total opioid consumption up to 72 h after surgery. The data of postoperative pain scores, epidural local anesthetic consumption, and adverse events from 193 patients were analyzed (continuous epidural infusion: n = 124, programmed intermittent epidural bolus: n = 69). There was no significant difference in the rescue opioid consumption in the 72-h postoperative period between the groups (33.3 mg [20.0–43.3] vs. 28.3 mg [18.3–43.3], p = 0.375). There were also no significant differences in the pain scores, epidural local anesthetic consumption, and incidence of adverse events. Our findings suggest that the quality of postoperative analgesia and safety following major upper abdominal surgery were comparable between the groups. However, the use of programmed intermittent epidural bolus requires further evaluation.

Efficacy of a Combination of Ketamine and Morphine for Intravenous Patient Controlled-Analgesia in Upper Abdominal Surgery: A Prospective, Double-blind, Randomized Controlled Trial

Background: Most postoperative upper abdominal pain is severe, and various methods can be employed to control it. Presently, morphine is the main drug used for anesthesia, but it may contribute to the occurrence of many uncomfortable side effects. Ketamine is an analgesic drug that inhibits NMDA receptors, making it a synergistic effect of morphine. Objective: To investigate the efficacy of a combination of ketamine and morphine in controlling postoperative upper abdominal pain. Materials and Methods: Informed consents were obtained from patients enrolled into the present double-blind randomized study that divided into two groups, (i) the M group, which received 1 mg/mL of morphine, and (ii) the MK group, which received 1 mg of ketamine plus 1 mg/mL of morphine as intravenous patient-controlled analgesia (IV-PCA) post-operation. All patients were assessed based on postoperative morphine consumption, a numeric rating scale (NRS) used to rate pain, and the presence of side effects. Results: Sixty-seven patients completed the study including 34 patients in the MK group and 33 patients in the M group. Cumulative postoperative morphine consumption at 24 and 48 hours was significantly lower in the MK group at 27.91±11.11 and 46.44±15.21 mg compared to the M group at 43.24±15.32 and 71.33±19.67 mg, respectively (p<0.001). NRS were similar between the two groups and no observable differences regarding to side effects. Conclusion: A combination of ketamine and morphine via IV PCA is effective in controlling postoperative upper abdominal pain. Keywords: Ketamine; Morphine; Upper abdominal surgery; Intravenous patient-controlled analgesia

Use of Incentive Spirometry in Adults following Cardiac, Thoracic, and Upper Abdominal Surgery to Prevent Post-Operative Pulmonary Complications: A Systematic Review and Meta-Analysis

<b><i>Background:</i></b> Currently, consensus on the effectiveness of incentive spirometry (IS) following cardiac, thoracic, and upper abdominal surgery has been based on randomized controlled trials (RCTs) and systematic reviews of lower methodological quality. To improve the quality of the research and to account for the effects of IS following thoracic surgery, in addition to cardiac and upper abdominal surgery, we performed a meta-analysis with thorough application of the Grading of Recommendations Assessment, Development and Evaluation scoring system and extensive reference to the Cochrane Handbook for Systematic Reviews of Interventions. <b><i>Objective:</i></b> The objective of this study was to determine, with rigorous methodology, whether IS for adult patients (18 years of age or older) undergoing cardiac, thoracic, or upper abdominal surgery significantly reduces30-day post-operative pulmonary complications (PPCs), 30-day mortality, and length of hospital stay (LHS) when compared to other rehabilitation strategies. <b><i>Methods:</i></b> The literature was searched using Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, CINAHL, and Web of Science for RCTs between the databases’ inception and March 2019. A random-effect model was selected to calculate risk ratios (RRs) with 95% confidence intervals (CIs). <b><i>Results:</i></b> Thirty-one RCTs involving 3,776 adults undergoing cardiac, thoracic, or upper abdominal surgery were included. By comparing the use of IS to other chest rehabilitation strategies, we found that IS alone did not significantly reduce 30-day PPCs (RR = 1.00, 95% CI: 0.88–1.13) or 30-day mortality (RR = 0.73, 95% CI: 0.42–1.25). Likewise, there was no difference in LHS (mean difference = −0.17,95% CI: −0.65 to 0.30) between IS and the other rehabilitation strategies. None of the included trials significantly impacted the sensitivity analysis and publication bias was not detected. <b><i>Conclusions:</i></b> This meta-analysis showed that IS alone likely results in little to no reduction in the number of adult patients with PPCs, in mortality, or in the LHS, following cardiac, thoracic, and upper abdominal surgery.