Objectives: Sepsis is a leading global cause of mortality, and predicting its outcomes is vital for improving patient care. This study explored the capabilities of ChatGPT, a state-of-the-art natural language processing model, in predicting in-hospital mortality for sepsis patients. Methods: This study utilized data from the Korean Sepsis Alliance (KSA) database, collected between 2019 and 2021, focusing on adult intensive care unit (ICU) patients and aiming to determine whether ChatGPT could predict all-cause mortality after ICU admission at 7 and 30 days. Structured prompts enabled ChatGPT to engage in in-context learning, with the number of patient examples varying from zero to six. The predictive capabilities of ChatGPT-3.5-turbo and ChatGPT-4 were then compared against a gradient boosting model (GBM) using various performance metrics. Results: From the KSA database, 4,786 patients formed the 7-day mortality prediction dataset, of whom 718 died, and 4,025 patients formed the 30-day dataset, with 1,368 deaths. Age and clinical markers (e.g., Sequential Organ Failure Assessment score and lactic acid levels) showed significant differences between survivors and non-survivors in both datasets. For 7-day mortality predictions, the area under the receiver operating characteristic curve (AUROC) was 0.70–0.83 for GPT-4, 0.51–0.70 for GPT-3.5, and 0.79 for GBM. The AUROC for 30-day mortality was 0.51–0.59 for GPT-4, 0.47–0.57 for GPT-3.5, and 0.76 for GBM. Zero-shot predictions using GPT-4 for mortality from ICU admission to day 30 showed AUROCs from the mid-0.60s to 0.75 for GPT-4 and mainly from 0.47 to 0.63 for GPT-3.5. Conclusions GPT-4 demonstrated potential in predicting short-term in-hospital mortality, although its performance varied across different evaluation metrics.

Background: Limited data are available on the mortality rates of patients receiving extracorporeal membrane oxygenation (ECMO) support for coronavirus disease 2019 (COVID-19). We aimed to analyze the relationship between COVID-19 and clinical outcomes for patients receiving ECMO. Methods: We retrospectively investigated patients with COVID-19 pneumonia requiring ECMO in 19 hospitals across Korea from January 1, 2020 to August 31, 2021. The primary outcome was the 90-day mortality after ECMO initiation. We performed multivariate analysis using a logistic regression model to estimate the odds ratio (OR) of 90-day mortality. Survival differences were analyzed using the Kaplan–Meier (KM) method. Results: Of 127 patients with COVID-19 pneumonia who received ECMO, 70 patients (55.1%) died within 90 days of ECMO initiation. The median age was 64 years, and 63% of patients were male. The incidence of ECMO was increased with age but was decreased after 70 years of age. However, the survival rate was decreased linearly with age. In multivariate analysis, age (OR, 1.048; 95% confidence interval [CI], 1.010–1.089; P = 0.014) and receipt of continuous renal replacement therapy (CRRT) (OR, 3.069; 95% CI, 1.312–7.180; P = 0.010) were significantly associated with an increased risk of 90-day mortality. KM curves showed significant differences in survival between groups according to age (65 years) (log-rank P = 0.021) and receipt of CRRT (log-rank P = 0.004). Conclusion Older age and receipt of CRRT were associated with higher mortality rates among patients with COVID-19 who received ECMO.

BACKGROUND: Beyond its current function as a rescue therapy in acute respiratory distress syndrome (ARDS), extracorporeal membrane oxygenation (ECMO) may be applied in ARDS patients with less severe hypoxemia to facilitate lung protective ventilation. The purpose of this study was to evaluate the efficacy of extended ECMO use in ARDS patients. METHODS: This study reviewed 223 adult patients who had been admitted to the intensive care units of 11 hospitals in Korea and subsequently treated using ECMO. Among them, the 62 who required ECMO for ARDS were analyzed. The patients were divided into two groups according to pre-ECMO arterial blood gas: an extended group (n=14) and a conventional group (n=48). RESULTS: Baseline characteristics were not different between the groups. The median arterial carbon dioxide tension/fraction of inspired oxygen (FiO2) ratio was higher (97 vs. 61, p<0.001) while the median FiO2 was lower (0.8 vs. 1.0, p<0.001) in the extended compared to the conventional group. The 60-day mortality was 21% in the extended group and 54% in the conventional group (p=0.03). Multivariate analysis indicated that the extended use of ECMO was independently associated with reduced 60-day mortality (odds ratio, 0.10; 95% confidence interval, 0.02–0.64; p=0.02). Lower median peak inspiratory pressure and median dynamic driving pressure were observed in the extended group 24 hours after ECMO support. CONCLUSION: Extended indications of ECMO implementation coupled with protective ventilator settings may improve the clinical outcome of patients with ARDS.
Adult ; Anoxia ; Carbon Dioxide ; Extracorporeal Membrane Oxygenation ; Humans ; Intensive Care Units ; Korea ; Lung ; Mortality ; Multicenter Studies as Topic ; Multivariate Analysis ; Oxygen ; Respiration, Artificial ; Respiratory Distress Syndrome, Adult ; Retrospective Studies ; Ventilation ; Ventilators, Mechanical

BACKGROUND: Beyond its current function as a rescue therapy in acute respiratory distress syndrome (ARDS), extracorporeal membrane oxygenation (ECMO) may be applied in ARDS patients with less severe hypoxemia to facilitate lung protective ventilation. The purpose of this study was to evaluate the efficacy of extended ECMO use in ARDS patients. METHODS: This study reviewed 223 adult patients who had been admitted to the intensive care units of 11 hospitals in Korea and subsequently treated using ECMO. Among them, the 62 who required ECMO for ARDS were analyzed. The patients were divided into two groups according to pre-ECMO arterial blood gas: an extended group (n=14) and a conventional group (n=48). RESULTS: Baseline characteristics were not different between the groups. The median arterial carbon dioxide tension/fraction of inspired oxygen (FiO2) ratio was higher (97 vs. 61, p<0.001) while the median FiO2 was lower (0.8 vs. 1.0, p<0.001) in the extended compared to the conventional group. The 60-day mortality was 21% in the extended group and 54% in the conventional group (p=0.03). Multivariate analysis indicated that the extended use of ECMO was independently associated with reduced 60-day mortality (odds ratio, 0.10; 95% confidence interval, 0.02–0.64; p=0.02). Lower median peak inspiratory pressure and median dynamic driving pressure were observed in the extended group 24 hours after ECMO support. CONCLUSION Extended indications of ECMO implementation coupled with protective ventilator settings may improve the clinical outcome of patients with ARDS.

BACKGROUND/AIMS: Many authors recommend performing a second-look endoscopy (SLE) to reduce the frequency of delayed bleeding after endoscopic submucosal dissection (ESD) for gastric neoplasms, but these recommendations have been made despite a lack of reliable evidence supporting the effectiveness of SLE. METHODS: From January 2012 to May 2013, we investigated 441 gastric neoplasms treated by ESD to assess the risk factors for delayed bleeding. Delayed bleeding occurred in four of these lesions within 1 postoperation day. Therefore, we enrolled the patients with the remaining 437 lesions to determine the utility of SLE performed on the morning of postoperative day 2. All lesions were randomly assigned to SLE (220 lesions) groups or non-SLE (217 lesions) groups. RESULTS: Delayed bleeding occurred in 18 lesions (4.1%). A large tumor size (>20 mm) was the only independent risk factor for delayed bleeding (p=0.007). The chance of delayed bleeding was not significantly different between the patients receiving a SLE (eight cases) and those patients not receiving a SLE (six cases, p=0.787). Furthermore, SLE for lesions with a large tumor size did not significantly decrease delayed bleeding (p=0.670). CONCLUSIONS: SLE had little or no influence on the prevention of delayed bleeding, irrespective of the risk factors.
Aged ; Dissection/*adverse effects ; Female ; Gastric Mucosa/*surgery ; *Gastroscopy ; Humans ; Male ; Middle Aged ; Postoperative Hemorrhage/*prevention & control ; Prospective Studies ; Risk Factors ; *Second-Look Surgery ; Single-Blind Method ; Stomach Neoplasms/complications/*surgery ; Time Factors

PURPOSE: To report an epidemiologic study of keratoplasty in which we analyze basic data of corneal transplants and corneal donations in Korea. METHODS: From June 2004 through October 2004, questionnaires were distributed to 25 hospitals. The questionnaires were about the characteristics of patients registered in eye banks for keratoplasty from May 2001 to April 2003, and about the results of keratoplasties performed from May 2002 to April 2003. RESULTS: The leading corneal diseases in patients registered for keratoplasty were infectious keratitis (22.0%), trauma (21.0%), and pseudophakic and aphakic bullous keratopathy (13.8%), in that order. The leading indications in corneal recipients were: trauma (15.5%), pseudophakic and aphakic bullous keratopathy (13.7%), and infectious keratitis (10.7%), in that order. In 233 cases of keratoplasties, penetrating keratoplasty was performed in 229 cases (98.3%) and lamellar keratoplasty was performed in 4 cases (1.7%). The most common combined surgery was cataract extraction. Common causes of graft failure were rejection of donor cornea and infection. Imported donor corneas were used in sixty-one cases (26.2%) among the 233 total keratoplasties. CONCLUSIONS: We constructed an epidemiologic data base of patients registered for keratoplasty, corneal donation, and the results of keratoplasties throughout Korea.
Cataract Extraction ; Cornea ; Corneal Diseases ; Corneal Transplantation* ; Epidemiologic Studies* ; Eye Banks ; Humans ; Keratitis ; Keratoplasty, Penetrating ; Korea* ; Surveys and Questionnaires ; Tissue Donors ; Transplants

PURPOSE: To report an epidemiologic study of keratoplasty in which we analyze basic data of corneal transplants and corneal donations in Korea. METHODS: From June 2004 through October 2004, questionnaires were distributed to 25 hospitals. The questionnaires were about the characteristics of patients registered in eye banks for keratoplasty from May 2001 to April 2003, and about the results of keratoplasties performed from May 2002 to April 2003. RESULTS: The leading corneal diseases in patients registered for keratoplasty were infectious keratitis (22.0%), trauma (21.0%), and pseudophakic and aphakic bullous keratopathy (13.8%), in that order. The leading indications in corneal recipients were: trauma (15.5%), pseudophakic and aphakic bullous keratopathy (13.7%), and infectious keratitis (10.7%), in that order. In 233 cases of keratoplasties, penetrating keratoplasty was performed in 229 cases (98.3%) and lamellar keratoplasty was performed in 4 cases (1.7%). The most common combined surgery was cataract extraction. Common causes of graft failure were rejection of donor cornea and infection. Imported donor corneas were used in sixty-one cases (26.2%) among the 233 total keratoplasties. CONCLUSIONS: We constructed an epidemiologic data base of patients registered for keratoplasty, corneal donation, and the results of keratoplasties throughout Korea.
Cataract Extraction ; Cornea ; Corneal Diseases ; Corneal Transplantation* ; Epidemiologic Studies* ; Eye Banks ; Humans ; Keratitis ; Keratoplasty, Penetrating ; Korea* ; Surveys and Questionnaires ; Tissue Donors ; Transplants

BACKGROUND: Nuss procedure used in pectus excavatum repair is preferred, because of its excellent effect from the cosmetic point of view and improved pulmonary function, but it cause severe pain due to thoracic expansion after the operation. This study was designed to evaluate effective fentanyl dose using an intravenous patient-controlled analgesia (IV-PCA) pump for pain control following pectus excavatum repair in pediatric patients. METHODS: Sixty patients undergoing elective thoracic surgery were randomly assigned to received fentanyl 0.5microgram/kg/hr (Group I, n = 20), 0.7microgram/kg/hr (Group II, n = 20), and 1.0microgram/kg/hr (Group III, n = 20) via an IV-PCA pump (basal, 1 ml/h; bolus, 0.5 ml; lock out interval, 30 min) after operation. A blind observer evaluated each patient using the Children's Hospital of Eastern Ontario pain scale (CHEOPS) and the faces scale (FS). Incidences of side effects and pain control satisfaction were assessed at postoperative 48 hrs. RESULTS: There were no significant differences in CHEOPS or FS score between the groups the postoperative 48 hrs period. CHEOPS and FS scores at 4 and 8 hrs in groups II and III were significantly lower than in group I (P<0.05), but all groups showed lower CHEOPS and FS scores during the first postoperative 48 hrs. Satisfaction of pain control assessment by mothers was significantly higher in groups II and III than in group I (P<0.05). CHEOPS and FS scores were highly correlated with each other (P<0.001). CONCLUSIONS: We conclude that infusion of fentanyl at 0.5microgram/kg/hr using an IV-PCA pump is effective for pain control of 5 years of age or older after Nuss procedure.
Analgesia, Patient-Controlled* ; Fentanyl* ; Funnel Chest* ; Humans ; Incidence ; Mothers ; Ontario ; Thoracic Surgery

Keratoprosthesis implantation is the only alternative method to restore vision in patients who might invariably fail allograft coneal transplantation. Seoul type keratoprosthesis adapted 20 micrometer pore sized expanded polytetrafluoroethyl-ene[PTFE, Gore-Tex]as a skirt material in this study. To evaluate compatibility of this material as a skirt we performed in vitro cell culture experiment and animal experiment. For in vitro experiment, expanded PTFE membrane was cultured with rabbit keratocytes in 24-well culture plate for a week.For animal experiment Seoul type keratoprosthesis was implanted in the rabbit cornea. Two months after the operation specimens for pathologic examination were retrieved. In culture experiment no keratocyte invaded pores. In animal experiment no keratocyte but only many inflammatory cells mainly polymorphonuclear leukocytes infiltrated pores of skirt and surrounding cornea. In conclusion, 20 micrometer pore sized expanded PTFE is not good as a skirt material of keratoprosthesis.
Allografts ; Animal Experimentation ; Cell Culture Techniques ; Cornea* ; Humans ; Membranes ; Neutrophils ; Polytetrafluoroethylene ; Seoul*

BACKGROUND: Dextromethorphan (DEX) is an NMDA receptor antagonist which has recently been introduced for the treatment of chronic pain mainly to reduce the central sensitization component of pain. It is also reported to reduce the pain from acute ischemia of an extremity in a rat model which has a similar mechanism as tourniquet pain. The purpose of this experiment was to see if dextromethorphan could reduce tourniquet pain in normal volunteers. METHODS: A double blind randomized cross-over test was done on ten healthy male volunteers. Each subject was orally administered with three different doses of DEX (placebo, 30, 60 mg) 1 h before the study according to a preallocated randomized table. The subject was not reallocated for the test within two weeks of the previous test. After a 10 minute acclimation period before each test, the degree of tourniquet pain measured by VAS, arterial blood pressure, heart rate, respiration rate, and pressure-evoked pain were measured before and every 5 minutes after inflation of the tourniquet until the subject felt unbearable pain. A mixed model for repeated measurement of data was used for statistical analysis (P < 0.05). RESULTS: There was no statistical difference between different doses of DEX including the placebo. Rather, there was a tendency that DEX increases the pain. And there also was a tendency that average time to reach unbearable pain was decreased by DEX (P > 0.05). CONCLUSIONS: DEX is not effective in controlling tourniquet pain in normal awake subjects.
Acclimatization ; Arterial Pressure ; Central Nervous System Sensitization ; Chronic Pain ; Dextromethorphan* ; Extremities ; Healthy Volunteers* ; Heart Rate ; Humans ; Inflation, Economic ; Ischemia ; Male ; Models, Animal ; N-Methylaspartate ; Respiratory Rate ; Tourniquets* ; Volunteers