Incidence, Outcomes, and Risk Factors of Intraoperative Cardiac Arrest During Orthotopic Liver Transplantation.

BACKGROUND: Intraoperative cardiac arrest (ICA) during liver transplantation (LT) is a rare surgical complication that results in devastating outcomes. Moreover, previous worldwide studies have found inconsistencies in the risk factors associated with ICA in LT. METHODS: This was a retrospective cohort study of adult patients who underwent LT between January and October 2021 at Siriraj Hospital, a tertiary care hospital. The incidence of ICA and outcomes of patients who experienced ICA were examined. Risk factors associated with ICA were investigated as a secondary objective. RESULTS: Among 342 patients, the incidence of ICA was 3.5% (95% CI 1.8%-6.1%). Of these, 33.3% died intraoperatively. Among patients with ICA, 41.7% died within 30 days, compared with only 7.6% in those without ICA (P = .002). Moreover, the in-hospital mortality rate of those with ICA was 58.3%, which was significantly higher than that of those without ICA (9.7%, P < .001). However, 41.7% of patients with ICA were discharged alive with long-term survival. Because ICA is a rare event, we found only 2 independent factors significantly associated with ICA. These factors include intraoperative temperature below 35°C, with an odds ratio (OR) of 6.07 (95% CI:1.32-27.88, P = .02) and elevated intraoperative serum potassium, with an OR of 4.57 (95% CI:2.15-9.67, P < .001). CONCLUSIONS: ICA is associated with high perioperative and in-hospital mortality. However, our findings suggest that with effective management of ICA, more than 40% of these patients could be discharged with excellent long-term outcomes. Hypothermia and hyperkalemia were independent risk factors significantly associated with ICA.

Adherence to lung protective mechanical ventilation in patients admitted to a surgical intensive care unit and the associated increased mortality.

Background: The adherence rate to the lung protective ventilation (LPV) strategy, which is generally accepted as a standard practice in mechanically ventilated patients, reported in the literature is approximately 40%. This study aimed to determine the adherence rate to the LPV strategy, factors associated with this adherence, and related clinical outcomes in mechanically ventilated patients admitted to the surgical intensive care unit (SICU). Methods: This prospective observational study was conducted in the SICU of a tertiary university-based hospital between April 2018 and February 2019. Three hundred and six adult patients admitted to the SICU who required mechanical ventilation support for more than 12 h were included. Ventilator parameters at the initiation of mechanical ventilation support in the SICU were recorded. The LPV strategy was defined as ventilation with a tidal volume of equal or less than 8 ml/kg of predicted body weight plus positive end-expiratory pressure of at least 5 cm H2O. Demographic and clinical data were recorded and analyzed. Results: There were 306 patients included in this study. The adherence rate to the LPV strategy was 36.9%. Height was the only factor associated with adherence to the LPV strategy (odds ratio for each cm, 1.10; 95% confidence interval (CI), 1.06-1.15). Cox regression analysis showed that the LPV strategy was associated with increased 90-day mortality (hazard ratio, 1.73; 95% CI, 1.02-2.94). Conclusion: The adherence rate to the LPV strategy among patients admitted to the SICU was modest. Further studies are warranted to explore whether the application of the LPV strategy is simply a marker of disease severity or a causative factor for increased mortality.

Intraoperative individualization of positive-end-expiratory pressure through electrical impedance tomography or esophageal pressure assessment: a systematic review and meta-analysis of randomized controlled trials.

PURPOSE: This systematic review of randomized-controlled trials (RCTs) with meta-analyses aimed to compare the effects on intraoperative arterial oxygen tension to inspired oxygen fraction ratio (PaO2/FiO2), exerted by positive end-expiratory pressure (PEEP) individualized trough electrical impedance tomography (EIT) or esophageal pressure (Pes) assessment (intervention) vs. PEEP not tailored on EIT or Pes (control), in patients undergoing abdominal or pelvic surgery with an open or laparoscopic/robotic approach. METHODS: PUBMED®, EMBASE®, and Cochrane Controlled Clinical trials register were searched for observational studies and RCTs from inception to the end of August 2022. Inclusion criteria were: RCTs comparing PEEP titrated on EIT/Pes assessment vs. PEEP not individualized on EIT/Pes and reporting intraoperative PaO2/FiO2. Two authors independently extracted data from the enrolled investigations. Data are reported as mean difference and 95% confidence interval (CI). RESULTS: Six RCTs were included for a total of 240 patients undergoing general anesthesia for surgery, of whom 117 subjects in the intervention group and 123 subjects in the control group. The intraoperative mean PaO2/FiO2 was 69.6 (95%CI 32.-106.4 ) mmHg higher in the intervention group as compared with the control group with 81.4% between-study heterogeneity (p < 0.01). However, at meta-regression, the between-study heterogeneity diminished to 44.96% when data were moderated for body mass index (estimate 3.45, 95%CI 0.78-6.11, p = 0.011). CONCLUSIONS: In patients undergoing abdominal or pelvic surgery with an open or laparoscopic/robotic approach, PEEP personalized by EIT or Pes allowed the achievement of a better intraoperative oxygenation compared to PEEP not individualized through EIT or Pes. PROSPERO REGISTRATION NUMBER: CRD 42021218306, 30/01/2023.

Effects of intra-operative positive end-expiratory pressure setting guided by oesophageal pressure measurement on oxygenation and respiratory mechanics during laparoscopic gynaecological surgery: A randomised controlled trial.

BACKGROUND: The creation of pneumoperitoneum during laparoscopic surgery can lead to adverse effects on the respiratory system. Positive end-expiratory pressure (PEEP) plays an important role in mechanical ventilation during laparoscopic surgery. OBJECTIVE: To evaluate whether PEEP setting guided by oesophageal pressure (Poeso) measurement would affect oxygenation and respiratory mechanics during laparoscopic gynaecological surgery. DESIGN: A randomised controlled study. SETTING: A single-centre trial from March 2018 to June 2018. PATIENTS: Forty-four adult patients undergoing laparoscopic gynaecological surgery with anticipated duration of surgery more than 2 h. INTERVENTION: PEEP set according to Poeso measurement (intervention group) versus PEEP constantly set at 5 cmH2O (control group). MAIN OUTCOME MEASURES: Gas exchange and respiratory mechanics after induction and intubation (T0) and at 15 and 60 min after initiation of pneumoperitoneum (T1 and T2, respectively). RESULTS: PEEP during pneumoperitoneum was significantly higher in the intervention group than in the control group (T1, 12.5 ±â€Š1.9 vs. 5.0 ±â€Š0.0 cmH2O and T2, 12.4 ±â€Š1.9 vs. 5.0 ±â€Š0.0 cmH2O, both P < 0.001). Partial pressures of oxygen decreased significantly from baseline during pneumoperitoneum in the control group but not in the intervention group. Nevertheless, the changes in partial pressures of oxygen did not differ between groups. Compliance of the respiratory system (CRS) significantly decreased and driving pressure significantly increased during pneumoperitoneum in both groups. However, the changes in CRS and driving pressure were significantly less in the intervention group. Transpulmonary pressure during expiration was maintained in the intervention group while it decreased significantly in the control group. CONCLUSION: PEEP setting guided by Poeso measurement showed no beneficial effects in terms of oxygenation but respiratory mechanics were better during laparoscopic gynaecological surgery. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT03256396.

Lumbar skeletal muscle index derived from routine computed tomography exams predict adverse post-extubation outcomes in critically ill patients.

PURPOSE: To evaluate the effect of a skeletal muscle index derived from a routine CT image at the level of vertebral body L3 (L3SMI) on outcomes of extubated patients in the surgical intensive care unit. MATERIALS AND METHODS: 231 patients of a prospective observational trial (NCT01967056) who had undergone CT within 5days of extubation were included. L3SMI was computed using semi-automated segmentation. Primary outcomes were pneumonia within 30days of extubation, adverse discharge disposition and 30-day mortality. Secondary outcomes included re-intubation within 72h, total hospital costs, ICU length of stay (LOS), post-extubation LOS and total hospital LOS. Outcomes were analyzed using multivariable regression models with a priori-defined covariates height, gender, age, APACHE II score and Charlson Comorbidity Index. RESULTS: L3SMI was an independent predictor of pneumonia (aOR 0.96; 95% CI 0.941-0.986; P=0.002), adverse discharge disposition (aOR 0.98; 95% CI 0.957-0.999; P=0.044) and 30-day mortality (aOR 0.94; 95% CI 0.890-0.995; P=0.033). L3SMI was significantly lower in re-intubated patients (P=0.024). Secondary analyses suggest that L3SMI is associated with total hospital costs (P=0.043) and LOS post-extubation (P=0.048). CONCLUSION: The lumbar skeletal muscle index, derived from routine abdominal CT, is an objective prognostic tool at the time of extubation.

Endotracheal Tubes Cleaned With a Novel Mechanism for Secretion Removal: A Randomized Controlled Clinical Study.

INTRODUCTION: Intubation compromises mucus clearance, allowing secretions to accumulate inside the endotracheal tube (ETT). The purpose of this trial was to evaluate a novel device for ETT cleaning. We hypothesized that its routine use would reduce tube occlusion due to mucus accumulation, while decreasing airway bacterial colonization. METHODS: Subjects were randomized to either the use of the device every 8 h, or the institutional standard of care (blind tracheal suction) only. ETTs were collected at extubation and analyzed with high-resolution computed tomography (HRCT) for quantification of mucus volume. Microbiological testing was performed on biofilm samples. Vital signs and ventilatory settings were collected at the bedside. In-hospital follow-up was conducted, and a final evaluation survey was completed by respiratory therapists. RESULTS: Seventy-four subjects expected to remain intubated for longer than 48 h were enrolled (77 ETTs, 37 treatment vs 40 controls). Treated tubes showed reduced mucus accumulation (0.56 ± 0.12 vs 0.71 ± 0.28 mL; P = .004) and reduced occlusion (6.3 ± 1.7 vs 8.9 ± 7.6%; P = .039). The HRCT slice showing the narrowest lumen within each ETT exhibited less occlusion in cleaned tubes (10.6 ± 8.0 vs 17.7 ± 13.4%, 95% CI: 2-12.1; P = .007). Data on microbial colonization showed a trend in the treatment group toward a reduced ETT-based biomass of bacteria known to cause ventilator-associated pneumonia. No adverse events were reported. The staff was satisfied by the overall safety and feasibility of the device. CONCLUSION: The endOclear is a safe and effective device. It prevents luminal occlusion, thereby better preserving ETT nominal function.

The Association between Red Blood Cell Transfusion and Hospital Mortality in Critically Ill Surgical Patients: The Multi-center Thai University-Based Surgical Intensive Care Units Study (THAI-SICU Study).

Objective: Red blood cell transfusion (RBCT) is commonly prescribed to critically ill patients with anemia. Nevertheless, the benefits of RBCT in these patients, particularly critically ill surgical patients, are still controversial. The aim of this study is to explore the association between RBCT and hospital mortality in Thai critically ill surgical patients. Material and Method: This study was a part of the multi-center, prospective, observational study, which included adult patients admitted to the SICUs after surgery. Patients were categorized into transfusion and no transfusion groups according to whether they received RBCT during SICU stay or not. The multiple logistic regression analysis was performed to determine whether RBCT was an independent risk factor for hospital mortality. The patients were also matched between two groups based on the propensity score for RBCT requirement and were then compared. Results: There were 2,531 patients included in this study. The incidence of RBCT in SICU was 40.3%. Overall, there was no association between RBCT in SICU and hospital mortality (adjusted OR 1.33, 95% CI 0.83-2.11) except in the subgroup of patients with age of <65 years old (adjusted OR 1.99, 95% CI 1.03-3.84). However, when the amount of RBCT was more than 1,200 mL, it was independently associated with increased hospital mortality (adjusted OR 2.55, 95% CI 1.35-4.81). In the propensity-score matching cohort, there was no association between RBCT in SICU and hospital mortality (adjusted OR 1.56, 95% CI 0.88-2.77) except when the amount of RBCT was more than 600 mL (601-1,200 mL, adjusted OR 3.14, 95% CI 1.47-6.72 and >1,200 mL, adjusted OR 3.58, 95% CI 1.36-9.48). Conclusion: RBCT should be considered as a life-saving intervention but with potential risks of adverse events. Identifying patients who will likely gain benefit from RBCT and implementing the restrictive transfusion strategy may be the keys to improve outcomes.

Incidence and Risk Factors of Unplanned Extubation in Critically Ill Surgical Patients: The Multi-center Thai University-based Surgical Intensive Care Units Study (THAI-SICU Study).

Objective: Unplanned extubation (UE) is one of the most troubling events in critically ill patients who require endotracheal intubation and mechanical ventilation. The aims of this study are to determine the incidence and to identify the risk factors associated with UE in critically ill surgical patients. Material and Method: This was a multi-center prospective observational cohort study, which included surgical patients admitted to nine university-based surgical intensive care units (SICUs) in Thailand between April 2011 and January 2013. UE was defined as deliberate extubation by patients (self-extubation) or accidental extubation during procedures or transportation. The incidence of UE was calculated, the adjusted logistic regression model was performed to determine the independent risk factors for UE and the outcomes were compared between those with planned extubation and UE. Results: 2,890 patients required endotracheal intubation and mechanical ventilation were included in the analysis. Of these, 54 patients experienced UE and, therefore, the incidence of UE was 1.9%. Five independent risk factors for UE were identified; congestive heart failure (adjusted odds ratio, OR, 3.48; 95% CI, 1.29-9.40), emergency surgery (adjusted OR, 2.18; 95% CI, 1.01-4.74), non-postoperative status (adjusted OR, 2.37; 95% CI, 1.05-5.37), sedation usage (adjusted OR, 3.19; 95% CI, 1.72-5.93) and delirium (adjusted OR, 3.61; 95% CI, 1.71-7.60). ICU length of stay (LOS) was significantly longer in patients with UE than those with planned extubation (adjusted coefficient, 2.76; 95% CI, 1.34-4.19). There was no significant difference between the two groups in terms of hospital LOS as well as ICU and 28-day mortality. Conclusion: The incidence of UE in critically ill surgical patients was 1.9%. Five independent risk factors for UE were: underlying congestive heart failure, emergency surgery, non-postoperative status, sedation usage, and delirium. Patients with UE had significantly longer ICU LOS than those with planned extubation.

Prospective Observational Study of Predictors of Re-Intubation Following Extubation in the Surgical ICU.

BACKGROUND: Re-intubation is associated with high morbidity and mortality. There is limited information regarding the risk factors that predispose patients admitted to the surgical ICU to re-intubation. We hypothesized that preoperative comorbidities, acquired muscular weakness, and renal dysfunction would be predictors of re-intubation in the surgical ICU population. METHODS: This was a prospective observational study in 2 surgical ICUs of a large tertiary hospital. All patients who were extubated during their surgical ICU stay were included. Demographic and clinical data were collected before and after extubation. The primary outcome was re-intubation within 72 h. Using multivariate logistic regression analysis, independent risk factors of re-intubation were determined, and a prediction score was developed. RESULTS: Between December 1, 2012, and January 31, 2014, we included 764 consecutive subjects. Of these, 65 subjects (8.5%) required re-intubation. Independent risk factors of re-intubation were blood urea nitrogen level of >8.2 mmol/L (odds ratio [OR] 3.66, 95% CI 1.97-6.80), hemoglobin level of <75 g/L (OR 2.10, 95% CI 1.23-3.61), and muscle strength of ≤3 (OR 2.03, 95% CI 1.16-3.55). The presence of all 3 risk factors was associated with an estimated probability for re-intubation of 26.8%. CONCLUSIONS: In noncardiac surgery, surgical ICU subjects, elevated blood urea nitrogen level, low hemoglobin level, and muscle weakness were identified as independent risk factors for re-intubation. The presence of these risk factors can potentially aid clinicians in making informed decisions regarding optimal airway management in patients considered for an extubation attempt. (ClinicalTrials.gov registration NCT01967056.).

Evaluation of the Infection-Related Ventilator-Associated Events Algorithm for Ventilator-Associated Pneumonia Surveillance in a Trauma Population.

BACKGROUND: The Centers for Disease Control and Prevention have recently introduced new ventilator-associated pneumonia (VAP) surveillance on the basis of the infection-related ventilator-associated complication (IVAC) definition. We aim to evaluate the accuracy of this new IVAC algorithm for detecting VAP according to the 2008 Centers for Disease Control and Prevention/National Healthcare Safety Network (NHSN) definition as the reference diagnosis (VAP-NHSN) in high-risk trauma patients. METHODS: This retrospective single-center study included all trauma subjects who were admitted to the ICU, required mechanical ventilation for >48 h, and received a blood transfusion. The new IVAC surveillance and the criteria for VAP-NHSN diagnosis were applied. The accuracy of the new IVAC surveillance for detecting VAP-NHSN was determined, and the clinical outcomes were compared between groups. RESULTS: The sensitivity, specificity, and positive and negative predictive values of IVAC for VAP-NSHN identification were 28.12%, 91.45, 58.06%, and 75.14%, respectively. Subjects with IVAC, VAP-NHSN, or both had higher morbidity when compared with those without IVAC and VAP-NHSN. Subjects with IVAC only had lower morbidity compared with those with VAP-NHSN only or those with both IVAC and VAP-NHSN. There was no significant difference in clinical outcomes between subjects with VAP-NHSN only and those with both IVAC and VAP-NHSN. CONCLUSIONS: IVAC criteria had a low accuracy for identifying VAP-NHSN in subjects with high-risk trauma.

Tracheal tube obstruction in mechanically ventilated patients assessed by high-resolution computed tomography.

BACKGROUND: Tracheal intubation compromises mucus clearance and secretions accumulate inside the tracheal tube (TT). The aim of this study was to evaluate with a novel methodology TT luminal obstruction in critically ill patients. METHODS: This was a three-phase study: (1) the authors collected 20 TTs at extubation. High-resolution computed tomography (CT) was performed to determine cross-sectional area (CSA) and mucus distribution within the TT; (2) five TTs partially filled with silicone were used to correlate high-resolution CT results and increased airflow resistance; and (3) 20 chest CT scans of intubated patients were reviewed for detection of secretions in ventilated patients' TT. RESULTS: Postextubation TTs showed a maximum CSA reduction of (mean±SD) 24.9±3.9% (range 3.3 to 71.2%) after a median intubation of 4.5 (interquartile range 2.5 to 6.5) days. CSA progressively decreased from oral to lung end of used TTs. The luminal volume of air was different between used and new TTs for all internal diameters (P<0.01 for new vs. used TTs for all studied internal diameters). The relationship between pressure drop and increasing airflow rates was nonlinear and depended on minimum CSA available to ventilation. Weak correlation was found between TT occlusion and days of intubation (R²=0.352, P=0.006). With standard clinical chest CT scans, 6 of 20 TTs showed measurable secretions with a CSA reduction of 24.0±3.9%. CONCLUSIONS: TT luminal narrowing is a common finding and correlates with increased airflow resistance. The authors propose high-resolution CT as a novel technique to visualize and quantify secretions collected within the TT lumen.

Incidence of red blood cell transfusion in mechanically ventilated surgical patients at Siriraj Hospital.

BACKGROUND: Anemia is commonly encountering surgical critically ill patients. The incidence of red blood cell (RBC) transfusion and transfusion trigger in this population has not been previously reported in a large tertiary care center in Thailand OBJECTIVE: To describe the incidence of RBC transfusion and transfusion trigger and to determine the factors and outcomes associated with RBC transfusion. MATERIAL AND METHOD: Data of 288 adult surgical patients requiring mechanical ventilation for > 24 hours was retrospectively reviewed Patient characteristic, outcomes, and transfusion data were collected. RESULTS: The incidence ofRBC transfusion was 83.0% (95% confidence interval (CI) 78.0-87.0%). The mean hemoglobin level before RBC transfusion was 8.7 +/- 1.2 g/dL. Patients who received RBC transfusion had significantly higher morbidity and mortality when compared with those who did not. Independent factors associated with RBC transfusion were low body weight, high Sequential Organ Failure Assessment (SOFA) score, and low hemoglobin level on admission (adjusted odds ratio 0.97, 1.19, and 0.60. respectively). CONCLUSION: In critically ill adult surgical patients, the incidence of RBC transfusion and transfusion trigger remained within high threshold Large randomized controlled studies are warranted to confirm potential benefit of RBC transfusion in surgical critically ill patients.

Postoperative sore throat: incidence, risk factors, and outcome.

BACKGROUND: Postoperative sore throat (POST) has been one of the most common complaints after anesthesia. In Siriraj Hospital, a high volume of general anesthesia is performed annually, but there was limited data regarding this complaint. OBJECTIVE: To describe the incidence of POST and to determine risk factors associated with the occurrence of POST MATERIAL AND METHOD: Three hundred eighty seven patients were prospectively studied. Demographic data, airway management, and intra-operative data were recorded. Sore throat occurrence and its intensity at postoperative 24 hours as well as patient satisfaction were assessed. RESULTS: The overall incidence of POST was 35.7% (95% confidence interval [CI] 30.9-40. 7%) with the mean intensity of 29.8 +/- 21.2. Operation of the neck was found to be an independent risk factor of 24-hour POST (odds ration [OR] 3.43, 95% confidence interval [CI] 1.88-6.25, p < 0.001), whereas in gynecological surgery the occurrence was significantly attenuated (OR 0.49, 95% CI 0.26-0.95, p = 0.035). CONCLUSION: POST was common after general anesthesia. Careful airway management might be the key to prevent this occurrence and to improve the quality of anesthetic care.

Sedation and paralysis.

Sedation is used almost universally in the care of critically ill patients, especially in those who require mechanical ventilatory support or other life-saving invasive procedures. This review will focus on the sedation strategies for critically ill patients and the pharmacology of commonly used sedative agents. The role of neuromuscular blocking agents in the ICU will be examined and the pharmacology of commonly used agents is reviewed. Finally a strategy for rational use of these sedative and neuromuscular blocking agents in critically ill patients will be proposed.

Difficult intubation in the adult patients undergoing oropharygolaryngeal, neck, and maxillofacial procedures: Thai Anesthesia Incident Monitoring Study (Thai AIMS).

BACKGROUND: Difficult intubation is one of the common anesthetic related complications during the perioperative period. In the patients with pathology or disease involving the oropharyngolarynx, neck, or maxillo-facial region, they might have a potentially higher risk than the general population. OBJECTIVE: To determine the characteristics and the contributing factors of difficult intubation in the adult patients undergoing oropharyngolaryngeal, neck, and maxillofacial procedures, and the factors minimizing this incidence and the suggested corrective strategies. MATERIAL AND METHOD: All incident reports of difficult intubation in the adult patients who received general anesthesia for the procedure involving the oropharyngolarynx, neck, and maxillofacial region from the Thai Anesthesia Incident Monitoring Study (Thai AIMS) database were identified. The details of the reports, the contributing factors, the factors those minimizing the incident, and the suggestive corrective strategies were studied. RESULTS: There were 26 (1.3%) incident reports of difficult intubation from the database. This occurred in 35%, 58%, and 15% of the patients with Mallampati class 1-2, thyromental distance equal or more than 5 cm or 3 fingerbreadths, and combined both parameters, respectively. Forty two percent of cases were judged as an unplanned difficult intubation. Twenty-seven, 23, and 19 percent of the patients had tumor or carcinoma at the oropharyngolarynx, deep neck infection, and maxillofacial fracture, respectively. Nearly half of the adverse events accompanied with difficult intubation were desaturation. No immediate fatally and late outcome was reported. Patients' disease/anatomy was the major contributing factor that might relate to the incidence. Previous experience, experienced assistance, and high vigilance were the factors minimizing incidence. Suggestive corrective strategies were guideline practices, additional training, and improved supervision. CONCLUSION: Carefully preoperative airway assessment and additional attention focused on the pathology or disease were the principle tasks. Algorithms for both anticipated and unanticipated difficult airway as well as alternative airway equipments should be implemented.