Abstract
BACKGROUND
The timing of extubation after general anesthesia (GA) in patients with acute ischemic stroke treated with mechanical thrombectomy (MT) is a significant issue. Prolonged duration of mechanical ventilation is considered to be an independent risk factor that negatively affects functional survival in patients receiving neurocritical care. This study evaluated the effect of time to extubation and the development of pneumonia on clinical prognosis after MT performed under GA.
METHODS
This retrospective, single-center, observational study included patients ≥18 years of age who underwent MT under GA for acute ischemic stroke between January 2023 and May 2025. Patient data were retrospectively obtained from hospital records and supplemented, when necessary, with information from patients’ relatives. Demographic data, lengths of intensive care unit and hospital stay, additional complications, neurological functional status (modified Rankin Scale [mRS]) at discharge, and mortality were examined. Patients were evaluated according to extubation timing, pneumonia, discharge mRS score (0–2, favorable; 3–6, unfavorable), and 30-day mortality using multivariate logistic regression analysis.
RESULTS
Data from 119 patients (mean age, 70.3±13.6 years) were analyzed. Patients in whom time to extubation was >24 h were older (p=0.003), exhibited a lower pre-procedural Glasgow Coma Scale (GCS) score (p<0.001), and higher pneumonia and mortality rates (p<0.001). Logistic regression analyses revealed that time to extubation >24 h significantly increased the likelihood of an unfavorable mRS score and mortality (p<0.001). Lower pre-procedural GCS (odds ratio [OR] 0.64; p<0.001) and higher American Society of Anesthesiologists Physical Status (ASA-PS) classification (OR 27.966; p<0.002) scores significantly affected time to extubation. A high ASA-PS score was found to increase the probability of pneumonia by tenfold (95% confidence interval 1.1–100.9). Patients with pneumonia exhibited significantly higher mRS scores (p<0.001).
CONCLUSION
Although the time to extubation had a significant impact on poor neurological prognosis and mortality in patients undergoing MT for acute stroke, the development of pneumonia appeared to be associated with unfavorable early neurological functional outcomes.
Keywords: Acute ischemic stroke, general anesthesia, pneumonia, prognosis, thrombectomy
Abstract
AMAÇ
Akut iskemik inme geçiren ve mekanik trombektomi (MT) ile tedavi edilen hastalarda genel anestezi (GA) sonrası ekstübasyon zamanlaması önemli bir konudur. Mekanik ventilasyonun uzun süresi, nörokritik bakım alan hastalarda fonksiyonel sağkalımı olumsuz etkileyen bağımsız bir risk faktörü olarak kabul edilmektedir. Bu çalışma, GA altında yapılan MT sonrası ekstübasyon zamanının ve pnömoni gelişiminin klinik prognoz üzerindeki etkisini değerlendirmiştir.
GEREÇ VE YÖNTEM
Bu retrospektif, tek merkezli, gözlemsel çalışma, Ocak 2023 ile Mayıs 2025 tarihleri arasında akut iskemik inme nedeniyle GA altında MT uygulanan ≥18 yaş hastaları içermiştir. Hasta verileri, hastane kayıtlarından retrospek-tif olarak elde edilmiş ve gerektiğinde hastaların yakınlarından alınan bilgilerle desteklenmiştir. Demografik ver-iler, yoğun bakım ünitesi ve hastane yatış süreleri, ek komplikasyonlar, taburculukta nörolojik fonksiyonel du-rum (modifiye Rankin Ölçeği [mRS]) ve mortalite incelenmiştir. Hastalar, ekstübasyon zamanlaması, pnömoni, taburculuk mRS skoru (0–2, olumlu; 3–6, olumsuz) ve 30 günlük mortaliteye göre çok değişkenli lojistik re-gresyon analizi kullanılarak değerlendirilmiştir.
BULGULAR
Yüz on dokuz hastadan (ortalama yaş, 70.3±13.6 yıl) elde edilen veriler analiz edildi. Ekstübasyon süresi >24 saat olan hastalar daha yaşlıydı (p=0.003), işlem öncesi Glasgow Koma Ölçeği (GCS) skorları daha düşüktü (p<0.001) ve pnömoni ve ölüm oranları daha yüksekti (p<0.001). Lojistik regresyon analizleri, ekstübasyon sü-resinin >24 saat olmasının, olumsuz mRS skoru ve ölüm olasılığını önemli ölçüde artırdığını ortaya koydu (p<0.001). İşlem öncesi daha düşük GCS (OR 0.64; p<0.001) ve daha yüksek Amerikan Anesteziyologlar Derneği Fiziksel Durum (ASA-PS) sınıflandırması (OR 27.966; p<0.002) skorları, ekstübasyon süresini önemli ölçüde etkiledi. Yüksek ASA-PS skorunun pnömoni olasılığını on kat artırdığı bulundu (95% CI 1.1–100.9). Pnömonili hastalarda anlamlı derecede daha yüksek mRS skorları gözlendi (p<0.001).
SONUÇ
Akut inme nedeniyle mekanik trombektomi uygulanan hastalarda ekstübasyon süresinin nörolojik prognozun bozulması ve mortalite üzerinde önemli bir etkisi olmasına rağmen, pnömoni gelişimi de olumsuz erken nörolojik fonksiyonel sonuçlarla ilişkili görünmektedir.
Anahtar sözcükler: Akut iskemik inme, trombektomi, pnömoni, genel anestezi, prognoz
INTRODUCTION
Endovascular mechanical thrombectomy (MT) is a recommended treatment for acute ischemic stroke caused by the occlusion of large cerebral vessels. In clinical practice, MT is performed with patients under general anesthesia (GA), conscious sedation, or local anesthesia.[1,2] During GA, intubation and complete immobilization provide advantages, such as better angiographic imaging and shorter procedure time. However, due to the anesthetic drugs used during GA, there is a risk for hypotension, blood pressure fluctuations, and secondary changes in cerebral perfusion, as well as complications, including airway difficulties during intubation or aspiration.[3]
The effect of anesthetic techniques used during MT for acute ischemic stroke on clinical outcomes remains controversial. Some studies have reported that GA is associated with unfavorable neurological outcomes and an increased risk for complications.[4-6] In contrast, some randomized studies reported no difference between anesthetic techniques and suggested that GA may be associated with better functional outcomes than sedation.[7,8] These differences suggest that both the anesthesia technique and post-anesthesia care may be decisive factors affecting clinical prognosis.
The timing of extubation is an important clinical issue after intubation under GA. Prolonged mechanical ventilation is associated with adverse outcomes, such as ventilator-associated pneumonia and longer intensive care unit (ICU) and hospital lengths of stay, and is considered to be an independent risk factor that negatively affects functional survival in patients receiving neurocritical care.[9] Although there are no clear guidelines regarding optimal extubation timing in patients intubated and mechanically ventilated for acute ischemic stroke, mechanical ventilation lasting >24 h has been reported to be associated with worse neurological recovery and functional outcomes.[10,11]
As such, this retrospective study aimed to evaluate the impact of extubation timing and development of secondary pneumonia on mortality and neurological clinical prognosis (according to the modified Rankin Scale [mRS]) in patients undergoing MT under GA for acute ischemic stroke.
MATERIALS AND METHODS
The present investigation was a retrospective, single-center, observational study approved by the ethics committee. Data from patients ≥18 years of age with American Society of Anesthesiologists Physical Status (ASA-PS) classifications 1–4, who underwent MT under GA between January 2023 and May 2025, were retrospectively reviewed. These patients either presented to the authors’ hospital with acute ischemic stroke or were referred to the authors’ stroke unit from other centers.
Patients diagnosed with large-vessel occlusion in the anterior cerebral circulation (middle cerebral artery M1–M2 segments and/or internal carotid artery) or posterior cerebral circulation (basilar artery, vertebral artery, and/or posterior cerebral artery) detected using computed tomography (CT) angiography were included. Patients who developed aspiration before the procedure or during intubation, those with severe pre-procedural neurological sequelae (mRS score 3–6), radiologically confirmed intracranial hemorrhage before the procedure, pregnant women, pre-procedural ICU admission or need for mechanical ventilation, cases of intracranial hemorrhage during the procedure, and patients for whom data could not be accessed were excluded.
The medical records of 1012 patients, who underwent endovascular MT for acute ischemic stroke at the authors’ center, were retrospectively reviewed. After excluding 837 patients treated under local anesthesia or conscious sedation, data from 175 patients who underwent MT under GA with endotracheal intubation were evaluated. Of these, 52 were excluded due to missing data and refusal of the patient/relative to provide information for participation, 2 due to aspiration before the procedure, and 2 due to hemorrhagic transformation during the procedure. Ultimately, therefore, data from 119 patients who underwent MT under GA were analyzed.
In all patients, GA was administered under standard monitoring, including electrocardiography, heart rate, non-invasive blood pressure, peripheral oxygen saturation, and end-tidal carbon dioxide, using inhalational anesthesia and remifentanil infusion.
Data were obtained through the hospital’s electronic records system and telephone interviews with patients/relatives. Recorded demographic and clinical variables included age, sex, pre-procedural Glasgow Coma Scale (GCS), comorbidities, ASA-PS score, occlusion location, time of procedure, time from hospital admission to procedure (≤6 h or >6 h), time to extubation (≤24 h or >24 h), ICU admission and length of stay, total hospital length of stay, post-procedural pneumonia, intracranial hemorrhage, and severe cerebral ischemia/cerebral edema. The procedure time was categorized as daytime (regular working hours) and off-hours (nighttime, weekends, or holidays).
To evaluate prognosis, neurological status at discharge was determined using the mRS, and 30-day mortality was examined. mRS scores of 0–2 and 3–6 were considered to be favorable and unfavorable neurological functional outcomes, respectively. Pneumonia was defined as the presence of a new or progressive lung infiltration on chest radiography or thoracic CT within the first 7 days after the procedure, accompanied by ≥2 clinical findings, such as fever (>38°C), leukocytosis or leukopenia (leukocyte count >12 x 103/mL or <4 x 103/mL), purulent respiratory secretions, or increased oxygen requirement(s).[10] Due to the retrospective design of this study, it was not possible to differentiate between consistent microbiological culture results and ventilator-associated pneumonia; as such, pneumonia was evaluated based on clinical and radiological findings and considered within the context of pneumonia associated with early stroke.
Standardized stroke severity scores, such as the National Institutes of Health Stroke Scale (NIHSS), were not consistently available in the retrospective records; therefore, the GCS was used as a neurological assessment parameter.
The primary endpoints included discharge mRS score and 30-day mortality; the secondary endpoint was the development of pneumonia. Patients were grouped and compared according to time to extubation, presence of pneumonia, mRS outcomes, and mortality status.
The present study was approved by the Kartal Koşuyolu Specialized Training and Research Hospital Ethics Committee (Decision No: Koşuyolu-YİEAH-BAEK-2025/07/1118-1295). This study was conducted in accordance with the principles of the Declaration of Helsinki.
Statistical Analyses
Descriptive statistics are expressed as numbers and percentages for categorical variables, mean±standard deviation for normally distributed numerical variables, and median (interquartile range [IQR], i.e., 25th percentile–75th percentile) for non-normally distributed numerical variables. Differences in the distributions of time to extubation, pneumonia, mRS group, and survival status according to categorical variables were assessed using the chi-squared test. Differences between continuous variables were assessed using Student’s t-test for normally distributed parameters and the Mann–Whitney U test for non-normally distributed parameters. Factors affecting dependent variables were identified using binary logistic regression analysis. Analyses were performed using the Statistical Package for the Social Sciences version 26.0 (IBM Corporation, Armonk, NY, USA). Differences with p<0.05 were considered to be statistically significant.
RESULTS
This study included data from 119 patients (mean age, 70.3±13.6 years; 58% male) who underwent MT under GA. ASA-PS class 4 accounted for 69.7% of the patients, and 65.5% of the procedures were performed off-hours, whereas the remaining procedures were performed during the daytime.
The pre-procedural GCS score was >8 in 64.7% and ≤8 in 35.3% of patients. The time to extubation was >24 h in 55.5% of patients (n=66). The ICU admission rate was 79%, the median ICU length of stay was 4 days (IQR 1–12.5 days), and the median total hospital stay was 8 days (IQR 2–23 days). Post-procedural pneumonia occurred in 30.3% of patients, intracranial hemorrhage in 12.6%, and severe cerebral ischemia/cerebral edema in 10.1%. The median discharge mRS score was 5 (IQR 1–6); 38.7% (n=46) had favorable (i.e., mRS score 0–2) outcomes and 61.3% (n=73) had unfavorable (i.e., mRS score 3–6) outcomes. The 30-day mortality rate was 31.1% (Table 1).
Table 1.
Descriptive characteristics of patients, comorbidities, ICU admission, hospital and ICU length of stay, complications, mRS, and mortality rates
| Variable | n=119 (100.0) |
|---|---|
| Age (mean±SD) | 70.3±13.6 |
| Gender: Female/Male n (%) | 50 (42.0)/69 (58.0) |
| ASA 2/ASA 3/ASA 4 n (%) | 2 (1.7)/34 (28.6)/83 (69.7) |
| Time of procedure: Daytime/Off-hours n (%) | 41 (34.5)/78 (65.5) |
| Pre-procedural GCS (mean±SD) | 11.2±3.8 |
| Occlusion site n (%) | |
| Posterior circulation | 50 (42.0) |
| Anterior circulation | 69 (58.0) |
| Time to intervention n (%) | |
| ≤6 h | 74 (62.2) |
| >6 h | 45 (37.8) |
| Procedure duration (min) (mean±SD) | 53.8±28.0 |
| Anesthesia duration (min) (mean±SD) | 70.2±30.2 |
| Extubation time n (%) | |
| ≤24 h | 53 (44.5) |
| >24 h | 66 (55.5) |
| Presence of ICU admission n (%), days | 94 (79.0) |
| Length of ICU stay median (IQR), days | 4 (1–12.5) |
| Length of hospital stay median (IQR), days | 8 (2–23) |
| Complications | |
| Post-procedural pneumonia n (%) | 36 (30.3) |
| Post-procedural intracranial hemorrhage n (%) | 15 (12.6) |
| Severe cerebral ischemia/cerebral edema n (%) | 12 (10.1) |
| mRS median (IQR) | 5 (1–6) |
| mRS ≤2 (favorable) n (%) | 46 (38.65) |
| mRS 3–6 (unfavorable) n (%) | 73 (61.34) |
| Mortality (30 days) n (%) | 37 (31.1) |
SD: Standard deviation; IQR: Indicates interquartile range; ASA: American Society of Anesthesiologists physical status classification system; GCS: Glasgow Coma Scale; ICU: Intensive care unit; mRS: Modified Rankin Score.
The most common comorbidities were hypertension (73.9%), diabetes mellitus (33.6%), coronary artery disease (30.3%), and cerebrovascular disease (23.5%) (Table 2).
Table 2.
Patients’ comorbid diseases
| Comorbid diseases | n (%) |
|---|---|
| DM | 40 (33.6) |
| Hypertension | 88 (73.9) |
| CAD | 36 (30.3) |
| Arrhythmia | 10 (8.4) |
| Congestive heart failure | 17 (14.3) |
| Asthma -COPD | 11 (9.2) |
| Previous cerebrovascular disease | 28 (23.5) |
| Hypothyroidism | 8 (6.7) |
| CKD | 4 (3.4) |
| Malignancy | 9 (7.6) |
DM: Diabetes mellitus; CAD: Coronary artery disease; COPD: Chronic obstructive pulmonary disease; CKD: Chronic kidney disease.
Comparisons according to time to extubation
Patients with extubation time >24 h were older than those extubated ≤24 h (p=0.003). In this group, female sex, ASA-PS class 4, procedures performed during off-hours, lower pre-procedural GCS score, and anterior circulation occlusion were significantly more prevalent (all p<0.05).
The prevalence of pneumonia was markedly higher in patients with an extubation time >24 h (86.1% vs. 13.9%; p<0.001). In the same group, the rates of intracranial hemorrhage and severe cerebral ischemia/cerebral edema were significantly higher (p<0.05).
ICU and hospital lengths of stay were significantly longer in patients with extubation times >24 h (p<0.001). In addition, the 30-day mortality rate was significantly higher in this group (p<0.001). There was no significant difference in the distribution of comorbid diseases between the groups (p>0.05) (Table 3).
Table 3.
Patient comparisons according to time to extubation
| Variable | Extubation time ≤24 h (n=53) >24 h (n=66) | p | |
|---|---|---|---|
| Age med (IQR) | 66 (61–74.5) | 76 (65–85) | 0.0031 |
| Gender F/M n (%) | 16 (32.0)/37 (53.6) | 34 (68.0)/32 (46.4) | 0.0192 |
| ASA score n (%) | <0.0012 | ||
| ASA 2–3 | 35 (97.2) | 1 (2.8) | |
| ASA 4 | 18 (21.7) | 65 (78.3) | |
| Time of procedure n (%) | <0.0012 | ||
| Daytime | 34 (82.9) | 7 (17.1) | |
| Off-hours | 19 (24.4) | 59 (75.6) | |
| Pre-procedural GCS med (IQR) | 15 (15–15) | 8 (6–11) | <0.0012 |
| Occlusion site n (%) | 0.0322 | ||
| Posterior circulation | 28 (56.0) | 22 (44.0) | |
| Anterior circulation | 25 (36.2) | 44 (63.8) | |
| Intervention time n (%) | <0.0012 | ||
| ≤6 h | 18 (24.3) | 56 (75.7) | |
| >6 h | 35 (77.8) | 10 (22.2) | |
| Procedure duration (min) (IQR) | 50 (35–67.5) | 50 (30–70) | 0.9761 |
| Anesthesia duration (min) (IQR) | 70 (55–90) | 67.5 (45–80) | 0.4741 |
| ICU admission n (%) | 28 (29.8) | 66 (70.2) | <0.0012 |
| ICU length of stay med (IQR) | 1 (0–1.5) | 9 (4–36.5) | <0.0011 |
| Hospital length of stay med (IQR) | 4 (2–9.5) | 15 (5–40) | <0.0011 |
| Complications n (%) | |||
| Post-procedural pneumonia | 5 (13.9) | 31 (86.1) | <0.0012 |
| Post-procedural intracranial hemorrhage | 3 (20.0) | 12 (80.0) | 0.0412 |
| Post-procedural severe cerebral ischemia/edema | 2 (16.7) | 10 (83.3) | 0.0402 |
| mRS med (IQR) | 1 (0–2) | 6 (5–6) | <0.0011 |
| Mortality (30 days) n (%) | 2 (5.4) | 35 (94.6) | <0.0012 |
Mann-Whitney U test, 2Chi-square test. SD: Standard deviation; IQR: Indicates interquartile range; F: Female, M: Male; ASA: American Society of Anesthesiologists physical status classification system; GCS: Glasgow Coma Scale; ICU: Intensive care unit; mRS: Modified Rankin Score.
Comparison according to the development of pneumonia
Patients who developed pneumonia were older than those who did not (81.5 [IQR 67–87]) versus 68 [61–77] years; p=0.002). There were no significant differences in sex distribution (p>0.05). Pneumonia occurred significantly more frequently in patients with ASA class 4 and in those who underwent procedures during off-hours (P<0.001). The median pre-procedural GCS score was significantly higher in patients without pneumonia (15 [8–15] vs. 8 [6–10.75]); p<0.001).
The frequency of pneumonia was markedly higher in patients with an extubation time >24 h (47% vs. 9.4%; p<0.001). ICU and hospital stays were significantly longer in patients who developed pneumonia (p<0.001). These patients also exhibited higher mRS scores (p<0.001). However, there was no significant relationship between the development of pneumonia and 30-day mortality (p=0.226).
Functional outcome and mortality
An unfavorable mRS score was significantly more frequent in older patients, those with ASA class 4, procedures performed during off-hours, anterior circulation occlusion, and intervention time ≤6 h (all p≤0.001). An unfavorable mRS score was markedly higher in patients with an extubation time >24 h (p<0.001). In these patients, the ICU admission rate, ICU and hospital lengths of stay, and frequencies of pneumonia, intracranial hemorrhage, and severe cerebral ischemia/cerebral edema were significantly higher (Table 4).
Table 4.
Patient comparisons according to mRS score and 30-day mortality rate
| Variable | mRS | P | Mortality | P | ||
|---|---|---|---|---|---|---|
| Favorable (n=46) | Unfavorable (n=73) | Alive (n=82) | Deceased (n=37) | |||
| Age med (IQR) (mean±SD) | 66 (60.75–74.25) | 76 (64.5–85) | 0.0011 | 68.7±13.2 | 74.0±13.7 | 0.0513 |
| Sex (n)% | 0.0422 | <0.0012 | ||||
| Female | 14 (28.0) | 36 (72.0) | 25(50.0) | 25(50.0) | ||
| Male | 32 (46.4) | 37 (53.6) | 57(82.6) | 12(17.4) | ||
| ASA class (n) % | <0.0012 | <0.0012 | ||||
| ASA 2–3 | 29 (80.6) | 7 (19.4) | 34 (94.4) | 2 (5.6) | ||
| ASA 4 | 17 (20.5) | 66 (79.5) | 48 (57.8) | 35 (42.2) | ||
| Time of procedure n (%) | <0.0012 | <0.0012 | ||||
| Daytime | 30 (73.2) | 11 (26.8) | 37 (90.2) | 4 (9.8) | ||
| Off-hours | 16 (20.5) | 62 (79.5) | 45 (57.7) | 33 (42.3) | ||
| Pre-procedural GCS med (IQR) | 15 (15–15) | 8 (6.5–11) | <0.0012 | 15 (8–15) | 8 (7–11) | <0.0012 |
| Occlusion site (n)% | 0.0112 | 0.0092 | ||||
| Posterior Circ | 26 (52.0) | 24 (48.0) | 41 (82.0) | 9 (18.0) | ||
| Anterior Circ | 20 (29.0) | 49 (71.0) | 41 (59.4) | 28 (40.6) | ||
| Intervention time (n) % | <0.0012 | <0.0012 | ||||
| ≤6 h | 15 (20.3) | 59 (79.7) | 42 (56.8) | 32 (43.2) | ||
| >6 h | 31 (68.9) | 14 (31.1) | 40 (88.9) | 5 (11.1) | ||
| Procedure duration (min) med (IQR) | 45 (30–60) | 55 (30–70) | 0.3461 | 50 (30–70) | 50 (30–65) | 0.8991 |
| Anesthesia duration (min) med (IQR) | 62.5 (48.75–81.25) | 70 (45–87.5) | 0.8201 | 70 (45–90) | 70 (45–80) | 0.5421 |
| Extubation time (n)% | <0.0012 | <0.0012 | ||||
| ≤24 h | 41 (77.4) | 12 (22.6) | 51 (96.2) | 2 (3.8) | ||
| >24 h | 5 (7.6) | 61 (92.4) | 31 (47.0) | 35 (53.0) | ||
| ICU admission (n) % | 23 (24.5) | 71 (75.5) | <0.0012 | 58 (61.7) 2 | 36 (38.3) | 0.0012 |
| ICU length of stay med (IQR) | 0.5 (0–2) | 7.5 (3–35.75) | <0.0011 | 3 (0–21.5) | 5 (2–8.75) | 0.1781 |
| Hospital length of stay med (IQR) | 3.5 (2–12) | 12 (5–37) | <0.0011 | 12 (3–32.25) | 5 (2–8.75) | 0.0051 |
| Complications n (%) | ||||||
| Post-procedural pneumonia | 6 (16.7) | 30 (83.3) | 0.0012 | 22 (61.1) | 14 (38.9) | 0.2262 |
| Post-procedural intracranial hemorrhage | 1 (6.7) | 14 (93.3) | 0.0062 | 5 (33.3) | 10 (66.7) | 0.003*2 |
| Post-procedural severe cerebral ischemia/edema | 0 (0.0) | 12 (100.0) | 0.003*2 | 2 (16.7) | 10 (83.3) | <0.001* |
Fisher’s exact test was used. 1Mann–Whitney U test, 2Chi-square test; 3Student’s t-test.
Thirty-day mortality was significantly higher among females, those with ASA class 4, procedures performed off-hours, lower pre-procedural GCS scores, and prolonged time to extubation (all p<0.001). Anterior circulation location, intracranial hemorrhage, and severe cerebral ischemia/cerebral edema were also associated with mortality. While pneumonia was not associated with mortality, the hospital stay was longer among survivors (Table 4).
Logistic regression analyses
Logistic regression analyses revealed that patients with extubation time >24 h had a 41-fold higher likelihood of an unfavorable mRS score (odds ratio [OR] 41.6; 95% confidence interval [CI]: 13.7–127.2) and a 26-fold higher likelihood of 30-day mortality (OR 26.8; 95% CI: 5.9–123.2).
Prolonged time to extubation was independently associated with a low pre-procedural GCS score (OR 0.68; p<0.001) and high ASA-PS score (OR 27.96; p=0.002). Each 1-point increase in pre-procedural GCS score reduced the likelihood of extubation time >24 h by approximately 31% (95% CI: 0.571–0.828). In patients with ASA-PS class 4, the likelihood of extubation >24 h increased by approximately 28-fold (95% CI: 3.3–240.5), and the likelihood of pneumonia increased 10-fold (95% CI: 1.1–100.9) (Table 5).
Table 5.
Results of multivariable logistic regression analyses
| a. Factors affecting the mRS | |||||||
| Variable | B coefficient | S.E. | Wald | p | OR | %95 CI | |
| Constant | 0.636 | 0.285 | 4.998 | 0.025 | 1.890 | ||
| Time to extubation (ref: ≤24 h) | 3.730 | 0.569 | 42.928 | <0.001 | 41.683 | 13.657–127.222 | |
| Age, sex, ASA score, pneumonia, pre-procedural GCS, occlusion site, and time of procedure were included in the model but were not statistically significant. | |||||||
| b.Factors affecting mortality | |||||||
| Variable | B coefficient | S.E. | Wald | p | OR | %95 CI | |
| Constant | −1.532 | 0.388 | 15.568 | <0.001 | 0.216 | ||
| Sex (ref: male) | 1.448 | 0.496 | 8.513 | 0.004 | 4.254 | 1.608–11.250 | |
| Time to extubation (ref: ≤ 24 h) | 3.291 | 0.777 | 17.957 | <0.001 | 26.883 | 5.866–123.209 | |
| Age, sex, ASA score, pneumonia, pre-procedural GCS, occlusion site, and time of procedure were included in the model but did not reach statistical significance. | |||||||
| c.Factors affecting pneumonia development | |||||||
| Variable | B coefficient | S.E. | Wald | p | OR | %95 CI | |
| Constant | −1.853 | 0.521 | 12.651 | <0.001 | 0.157 | ||
| ASA group (ref: ASA 2–3) | 2.381 | 1.139 | 4.367 | 0.037 | 10.817 | 1.159–100.924 | |
| Time to extubation (ref: ≤24 h) | 1.131 | 0.608 | 3.461 | 0.063 | 3.098 | 0.941–10.199 | |
| Age, sex, pneumonia, pre-procedural GCS, occlusion site, and time of procedure were included in the model but did not reach statistical significance. | |||||||
| d. Factors affecting extubation timing | |||||||
| Variable | B coefficient | S.E. | Wald | p | OR | %95 CI | |
| Constant | 2.000 | 1.728 | 1.339 | 0.247 | 7.388 | ||
| Pre-procedural GCS | −0.375 | 0.095 | 15.649 | <0.001 | 0.687 | 0.571–0.828 | |
| ASA group (ref: ASA 2–3) | 3.331 | 1.098 | 9.207 | 0.002 | 27.966 | 3.252–240.472 | |
Age, sex, pneumonia, occlusion site, and time of procedure were included in the model but did not reach statistical significance. S.E: Standard error; OR: Odds ratio; CI: Confidence interval; ASA: American Society of Anesthesiologists; GCS: Glasgow Coma Scale.
The goodness-of-fit of the logistic regression model was assessed using the Hosmer–Lemeshow test, which revealed no evidence of poor model fit (p>0.05).
DISCUSSION
Results of this retrospective study revealed that a time to extubation exceeding 24 h was an independent risk factor for unfavorable neurological functional outcomes and 30-day mortality in patients undergoing MT under GA for acute stroke. In addition, the development of pneumonia was associated with prolonged time to extubation and poor functional outcomes but did not affect mortality. These findings indicate that the timing of post-procedural extubation is an important determinant of neurological prognosis, mortality, and respiratory complications.
However, patients with delayed extubation (>24 h) also had lower pre-procedural GCS scores, higher ASA-PS classifications, and a higher incidence of pneumonia, suggesting that extubation timing may reflect baseline clinical status and overall disease severity. Although these variables were included in the multivariate model, the relatively small sample size and predominance of unfavorable outcomes in the delayed extubation group may have contributed to the overestimation of effect size and wide CIs observed. Time to extubation may also be a surrogate marker of neurological severity rather than a directly modifiable causal determinant. Therefore, these findings should be interpreted as associations rather than causal relationships.
Adverse effects of prolonged time to extubation on clinical prognosis have also been demonstrated in previous studies. Fandler-Höfler et al.[11] reported that the time to extubation >24 h was associated with higher 90-day mRS scores in patients with anterior circulation acute stroke undergoing MT under GA, and that early extubation (≤6 h) was strongly associated with better functional outcomes. Similarly, Nikoubashman et al.[10] showed that prolonged mechanical ventilation (>24 h) was associated with unfavorable functional outcomes and 90-day mortality, but reported no additional difference in clinical outcomes between early (≤6 h) and delayed (6–24 h) extubation. Raming et al.[12] reported that late extubation reduced the likelihood of 90-day functional independence and survival after stroke, and demonstrated that extubation as soon as possible after the procedure was associated with more favorable prognostic outcomes. These reports support the findings of the present study. However, our study precludes commentary regarding the effects of different extubation timing within the first 24 h. Unlike previous studies, this study evaluated anterior and posterior circulation stroke cases together to enable the assessment of a broader patient group.
In our study, advanced age, high ASA-PS class, low pre-procedural GCS scores, procedures performed during off-hours, post-procedural hemorrhage, and progressive ischemia were significantly associated with unfavorable neurological outcomes and mortality. Beuker et al.[13] demonstrated a strong association between advanced age and prolonged mechanical ventilation and prognosis in their study evaluating long-term outcomes after thrombectomy. Nikoubashman et al.[10] showed that clinical factors, such as age, infarct size, and pneumonia, were associated with ventilation duration and had the greatest impact on functional outcome. Popat et al.[14] reported that the strongest predictors of mortality in patients with acute stroke were age and stroke volume calculated from radiographic imaging.
In our study, limiting mortality to 30 days and the relatively small sample size may explain why the association between age and mortality was not statistically evident. In addition, due to data limitations potentially related to the frequent performance of procedures during off-hours, pre-procedural neurological status was assessed only using the GCS, which may have limited the evaluation of the relationship between stroke severity and prognosis. However, in multivariate regression analyses, time to extubation emerged as the strongest determinant of both poor functional outcomes and mortality, independent of these factors.
In addition to time to extubation, female sex was a significant factor associated with mortality. This finding is consistent with those of previous studies. Appelros et al.[15] reported that, although stroke is more common among men worldwide, it tends to be more severe in women, and higher 30-day mortality rates have been observed among females (24.7% in women vs. 19.7% in men). Similarly, Reeves et al.[16] reported that women experience worse functional outcomes and a lower quality of life than men after stroke. Previous studies have also suggested that stroke occurs at an older age in women and is associated with a higher burden of age-related comorbidities, which may contribute to worse outcomes. Although our study did not include sex-based subgroup analyses, the number of males was higher. Mortality and adverse functional outcomes were more frequently associated with female sex.
We found that the frequency of pneumonia was significantly higher in patients with time to extubation >24 h. However, in the multivariate analyses, the time to extubation was not identified as an independent risk factor for pneumonia. Although advanced age, high ASA-PS score, and low pre-procedural GCS score were associated with the development of pneumonia, only high ASA score was an independent risk factor. This suggests that the development of pneumonia may be more closely related to underlying patient characteristics than to extubation timing.
Lin et al.[17] reported that a high stroke score was an important risk factor for early pneumonia (<7 days) in patients with acute stroke. Several studies have reported that pneumonia is strongly related to stroke severity and overall clinical condition.[18,19] Teh et al.[20] reported that stroke-associated pneumonia was associated with prolonged hospital stay, poor functional outcomes at discharge, and increased mortality for up to 1 year. In contrast, we observed longer ICU and hospital stays and more frequent unfavorable neurological functional outcomes (mRS score ≥3) in patients who developed pneumonia; however, pneumonia was not directly associated with 30-day mortality. Nevertheless, these findings should be interpreted with caution. The relatively short follow-up period and the limited sample size may have reduced the ability to detect an association between pneumonia and short-term mortality. In addition, early mortality in this patient population may be more strongly influenced by factors, such as stroke severity, lower GCS scores, hemorrhagic complications, cerebral edema, and prolonged mechanical ventilation, rather than pneumonia itself. Therefore, the absence of a statistically significant association between pneumonia and 30-day mortality should not be interpreted as evidence of lack of prognostic significance.
When factors affecting extubation timing were evaluated, low pre-procedural GCS and high ASA-PS scores were independent determinants of late extubation. This indicates that delayed extubation may be an expected outcome in patients with substantial systemic comorbidities and severe neurological status. Similarly, Lioutas et al.[21] reported significantly higher rates of extubation failure in patients with severe stroke. These results suggest that extubation decisions in patients with acute stroke should consider neurological status, systemic conditions, and respiratory parameters.
The present study had several limitations, the first of which was its retrospective design, which limits causal inferences. Second, the relatively small sample size may have reduced the statistical power. In addition, patients with missing baseline clinical or outcome data were excluded, which may have introduced selection bias and reduced statistical power because the missing data may not have been randomly distributed. Third, neurological assessment was limited to the GCS because standardized stroke severity scores, such as the NIHSS, were not consistently available in the retrospective records, likely due to the urgent nature of stroke management and frequent off-hour presentations with limited staffing. Therefore, GCS, which is the most consistently documented neurological assessment parameter, was used.
Finally, due to the difficulty in obtaining long-term follow-up data in this retrospective study, prognosis was assessed using the mRS at discharge; as such, our findings should be interpreted with caution. However, the results suggest that the timing of extubation in patients with acute stroke undergoing MT under GA may be associated with early clinical outcomes.
CONCLUSION
Prolonged time to extubation was associated with unfavorable neurological outcomes and increased mortality in patients with acute stroke who underwent MT under GA. However, this relationship should be interpreted with caution due to potential residual confounding factors related to stroke severity and overall clinical condition. Nevertheless, further prospective studies are required to confirm this association.
Footnotes
Cite this article as: Demiroluk O, Değer EA, Ersoz BS, Ofluoglu C, Yıldırım Ar A. Effect of extubation timing on prognosis in patients with acute stroke undergoing mechanical thrombectomy under general anesthesia: A retrospective study. Ulus Travma Acil Cerrahi Derg 2026;32:962-970.
Ethics Committee Approval
The present study was approved by the Kartal Koşuyolu Specialized Training and Research Hospital Ethics Committee (Date: 06.05.2025, Decision No: Koşuyolu-YİEAH-BAEK-2025/07/1118-1295).
Peer-review
Externally peer-reviewed.
Authorship Contributions
Concept: Ö.D., C.O., E.A.D, B.Ş.E.; Design: Ö.D., A.Y.A., B.Ş.E., C.O.; Supervision: Ö.D., A.Y.A.; Resource: Ö.D., A.Y.A., B.Ş.E.; Materials: E.A.D., Ö.D., A.Y.A., B.Ş.E.; Data collection and/or processing: Ö.D., E.A.D., B.Ş.E.; Analysis and/or interpretation: Ö.D., A.Y.A.; Literature review: Ö.D., E.A.D., A.Y.A.; Writing: Ö.D., A.Y.A.; Critical review: Ö.D., A.Y.A.
Informed Consent
Retrospective study.
Conflict of Interest
None declared.
Financial Disclosure
The author declared that this study has received no financial support.
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