Dexamethasone doses in patients with COVID-19 and hypoxia: A systematic review and meta-analysis.

BACKGROUND: The optimal dose of dexamethasone for severe/critical COVID-19 is uncertain. We compared higher versus standard doses of dexamethasone in adults with COVID-19 and hypoxia. METHODS: We searched PubMed and trial registers until 23 June 2023 for randomised clinical trials comparing higher (>6 mg) versus standard doses (6 mg) of dexamethasone in adults with COVID-19 and hypoxia. The primary outcome was mortality at 1 month. Secondary outcomes were mortality closest to 90 days; days alive without life support; and the occurrence of serious adverse events/reactions (SAEs/SARs) closest to 1 month. We assessed the risk of bias using the Cochrane RoB2 tool, risk of random errors using trial sequential analysis, and certainty of evidence using Grading of Recommendations Assessment, Development and Evaluation (GRADE). RESULTS: We included eight trials (2478 participants), of which four (1293 participants) had low risk of bias. Higher doses of dexamethasone probably resulted in little to no difference in mortality at 1 month (relative risk [RR] 0.97, 95% CI: 0.79-1.19), mortality closest to Day 90 (RR 1.01, 95% CI: 0.86-1.20), and SAEs/SARs (RR 1.00, 95% CI: 0.97-1.02). Higher doses of dexamethasone probably increased the number of days alive without invasive mechanical ventilation and circulatory support but had no effect on days alive without renal replacement therapy. CONCLUSIONS: Based on low to moderate certainty evidence, higher versus standard doses of dexamethasone probably result in little to no difference in mortality, SAEs/SARs, and days alive without renal replacement therapy, but probably increase the number of days alive without invasive mechanical ventilation and circulatory support.

Impact of Universal Use of the McGrath Videolaryngoscope as a Device for All Intubations in the Cardiac Operating Room. A Prospective Before-After VIDEOLAR-CAR Study.

OBJECTIVE: Tracheal intubation in cardiac surgery patients has a higher incidence of difficult laryngoscopic views compared with patients undergoing other types of surgery. The authors hypothesized that using the McGrath Mac videolaryngoscope as the first intubation option for cardiac surgery patients improves the percentage of patients with "easy intubation" compared with using a direct Macintosh laryngoscope. DESIGN: A prospective, observational, before-after study. SETTING: At a tertiary-care hospital. PARTICIPANTS: One thousand one hundred nine patients undergoing cardiac surgery. INTERVENTION: Consecutive patients undergoing cardiac surgery were intubated using, as the first option, a Macintosh laryngoscope (preinterventional phase) or a McGrath Mac videolaryngoscope (interventional phase). MEASUREMENTS AND MAIN RESULTS: The main objective was to assess whether the use of the McGrath videolaryngoscope, as the first intubation option, improves the percentage of patients with "easy intubation," defined as successful intubation on the first attempt, modified Cormack-Lehane grades of I or IIa, and the absence of the need for adjuvant airway devices. A total of 1,109 patients were included, 801 in the noninterventional phase and 308 in the interventional phase. The incidence of "easy intubation" was 93% in the interventional phase versus 78% in the noninterventional phase (p < 0.001). First-success-rate intubation was higher in the interventional phase (304/308; 98.7%) compared with the noninterventional phase (754/801, 94.1%; p = 0.005). Intubation in the interventional phase showed decreases in the incidence of difficult laryngoscopy (12/308 [3.9%] v 157/801 [19.6%]; p < 0.001), as well as moderate or difficult intubation (5/308 [1.6%] v 57/801 [7.1%]; p < 0.001). CONCLUSIONS: The use of the McGrath videolaryngoscope as the first intubation option for tracheal intubation in cardiac surgery improves the percentage of patients with "easy" intubation," increasing glottic view and first-success-rate intubation and decreasing the incidence of moderate or difficult intubation.

[Critical patients COVID-19 has changed the management and outcomes in the ICU after 1 year of the pandemic? A multicenter, prospective, observational study]. / Pacientes críticos COVID-19. ¿Han variado el manejo y los resultados en la UCI tras un año de pandemia? Estudio multicéntrico, prospectivo, observacional.

Objective: To compare the clinical characteristics, treatments, and evolution of critical patients with COVID-19 pneumonia treated in intensive care units (ICU) after one year of pandemic. Methodology: Multicenter, prospective study, which included critical COVID-19 patients in 9 ICUs in northwestern Spain. The clinical characteristics, treatments, and evolution of patients admitted to the ICU during the months of March-April 2020 (period 1) were compared with patients admitted in January-February 2021 (period 2). Results: 337 patients were included (98 in period 1 and 239 in period 2). In period 2, fewer patients required invasive mechanical ventilation (IMV) (65% vs. 84%, P < .001), using high-flow nasal cannulas (CNAF) more frequently (70% vs. 7%, P < .001), ventilation non-invasive mechanical (NIMV) (40% vs. 14%, P < .001), corticosteroids (100% vs. 96%, P = .007) and prone position in both awake (42% vs. 28%, P = .012), and intubated patients (67% vs. 54%, P = .034). The days of IMV, ICU stay and hospital stay were lower in period 2. Mortality was similar in the two periods studied (16% vs. 17%). Conclusions: After one year of pandemic, we observed that in patients admitted to the ICU, CNAF, NIMV, use of the prone position, and corticosteroids have been used more frequently, reducing the number of patients in IMV, and the length of stay in the ICU and hospital stay. Mortality was similar in the two study periods.

Effect of high versus low dose of dexamethasone on clinical worsening in patients hospitalised with moderate or severe COVID-19 pneumonia: an open-label, randomised clinical trial.

BACKGROUND: Low-dose dexamethasone demonstrated clinical improvement in patients with coronavirus disease 2019 (COVID-19) needing oxygen therapy; however, evidence on the efficacy of high-dose dexamethasone is limited. METHODS: We performed a randomised, open-label, controlled trial involving hospitalised patients with confirmed COVID-19 pneumonia needing oxygen therapy. Patients were randomly assigned in a 1:1 ratio to receive low-dose dexamethasone (6 mg once daily for 10 days) or high-dose dexamethasone (20 mg once daily for 5 days, followed by 10 mg once daily for an additional 5 days). The primary outcome was clinical worsening within 11 days since randomisation. Secondary outcomes included 28-day mortality, time to recovery and clinical status at day 5, 11, 14 and 28 on an ordinal scale ranging from 1 (discharged) to 7 (death). RESULTS: A total of 200 patients (mean±sd age 64±14 years; 62% male) were enrolled. 32 (31.4%) out of 102 patients enrolled in the low-dose group and 16 (16.3%) out of 98 in the high-dose group showed clinical worsening within 11 days since randomisation (rate ratio 0.427, 95% CI 0.216-0.842; p=0.014). The 28-day mortality was 5.9% in the low-dose group and 6.1% in the high-dose group (p=0.844). There was no significant difference in time to recovery, and in the seven-point ordinal scale at days 5, 11, 14 and 28. CONCLUSIONS: Among hospitalised COVID-19 patients needing oxygen therapy, high dose of dexamethasone reduced clinical worsening within 11 days after randomisation, compared with low dose.

Effectiveness of Prone Positioning in Nonintubated Intensive Care Unit Patients With Moderate to Severe Acute Respiratory Distress Syndrome by Coronavirus Disease 2019.

BACKGROUND: In the treatment for severe acute respiratory distress syndrome (ARDS) from coronavirus disease 2019 (COVID-19), the World Health Organization (WHO) recommends prone positioning (PP) during mechanical ventilation for periods of 12-16 h/d to potentially improve oxygenation and survival. In this prospective observational study, we evaluated the ability of long PP sessions to improve oxygenation in awake intensive care unit (ICU) patients with moderate or severe ARDS due to COVID-19. METHODS: The study was approved by the ethics committee of Galicia (code No. 2020-188), and all patients provided informed consent. In this case series, awake patients with moderate or severe ARDS by COVID-19 admitted to the ICU at University Hospital of Santiago from March 21 to April 5, 2020 were prospectively analyzed. Patients were instructed to remain in PP as long as possible until the patient felt too tired to maintain that position. Light sedation was administered with dexmedetomidine. The following information was collected: number and duration of PP sessions; tissue O2 saturation (StO2) and blood gases before, during, and following a PP session; need of mechanical ventilation; duration of ICU admission; and ICU outcome. Linear mixed-effects models (LMM) were fit to estimate changes from baseline with a random effect for patient. RESULTS: Seven patients with moderate or severe ARDS by COVID-19 were included. All patients received at least 1 PP session. A total of 16 PP sessions were performed in the 7 patients during the period study. The median duration of PP sessions was 10 hours. Dexmedetomidine was used in all PP sessions. Oxygenation increased in all 16 sessions performed in the 7 patients. The ratio of arterial oxygen partial pressure to fractional inspired oxygen (PaO2/FIO2) significantly increased during PP (change from baseline 110 with 97.5% confidence interval [CI], 19-202) and, after PP, albeit not significantly (change from baseline 38 with 97.5% CI, -9.2 to 85) compared with previous supine position. Similarly, tissue oxygenation underwent a small improvement during PP (change from baseline 2.6% with 97.5% CI, 0.69-4.6) without significant changes after PP. Two patients required intubation. All patients were discharged from the ICU. CONCLUSIONS: We found that PP improved oxygenation in ICU patients with COVID-19 and moderate or severe ARDS. PP was relatively well tolerated in our patients and may be a simple strategy to improve oxygenation trying to reduce the number of patients in mechanical ventilation and the length of stay in the ICU, especially in COVID-19 pandemic.

Reintubation in the ICU following cardiac surgery: is it more difficult than first-time intubation in the operating room?: A prospective observational study.

BACKGROUND: After cardiac surgery, a patient's trachea is usually extubated; however, 2 to 13% of cardiac surgery patients require reintubation in the ICU. OBJECTIVE: The objective of this study was to compare the initial intubation in the cardiac operating room with reintubation (if required) in the ICU following cardiac surgery. DESIGN: A prospective, observational study. SETTING: Department of Anesthesiology and Intensive Care Medicine, Clinical Hospital of Santiago, Spain. PATIENTS: With approval of the local ethics committee, over a 44-month period, we prospectively enrolled all cardiac surgical patients who were intubated in the operating room using direct laryngoscopy, and who required reintubation later in the ICU. MAIN OUTCOME MEASURES: The primary endpoint was to compare first-time success rates for intubation in the operating room and ICU. Secondary endpoints were to compare the technical difficulties of intubation (modified Cormack-Lehane glottic view, operator-reported difficulty of intubation, need for support devices for direct laryngoscopy) and the incidence of complications. RESULTS: A total of 122 cardiac surgical patients required reintubation in the ICU. Reintubation was associated with a lower first-time success rate than in the operating room (88.5 vs. 97.6%, P = 0.0048). Reintubation in the ICU was associated with a higher incidence of Cormack-Lehane grades IIb, III or IV views (34.5 vs. 10.7%, P < 0.0001), a higher incidence of moderate or difficult intubation (17.2 vs. 6.5%, P = 0.0001) and a greater need for additional support during direct laryngoscopy (20.5 vs. 10.7%, P = 0.005). Complications were more common during reintubations in the ICU (39.3 vs. 5.7%, P < 0.0001). CONCLUSION: Compared with intubations in the operating room, reintubation of cardiac surgical patients in the ICU was associated with more technical difficulties and a higher incidence of complications. CLINICAL TRIAL NUMBER: Ethics committee of Galicia number 2015-012.

Comparison of Tracheal Intubation Conditions in Operating Room and Intensive Care Unit: A Prospective, Observational Study.

WHAT WE ALREADY KNOW ABOUT THIS TOPIC: WHAT THIS ARTICLE TELLS US THAT IS NEW: BACKGROUND:: Tracheal intubation is a common intervention in the operating room and in the intensive care unit. The authors hypothesized that tracheal intubation using direct laryngoscopy would be associated with worse intubation conditions and more complications in the intensive care unit compared with the operating room. METHODS: The authors prospectively evaluated during 33 months patients who were tracheally intubated with direct laryngoscopy in the operating room, and subsequently in the intensive care unit (within a 1-month time frame). The primary outcome was to compare the difference in glottic visualization using the modified Cormack-Lehane grade between intubations performed on the same patient in an intensive care unit and previously in an operating room. Secondary outcomes were to compare first-time success rate, technical difficulty (number of attempts, operator-reported difficulty, need for adjuncts), and the incidence of complications. RESULTS: A total of 208 patients met inclusion criteria. Tracheal intubations in the intensive care unit were associated with worse glottic visualization (Cormack-Lehane grade I/IIa/IIb/III/IV: 116/24/47/19/2) compared with the operating room (Cormack-Lehane grade I/IIa/IIb/III/IV: 159/21/16/12/0; P < 0.001). First-time intubation success rate was lower in the intensive care unit (185/208; 89%) compared with the operating room (201/208; 97%; P = 0.002). Tracheal intubations in the intensive care unit had an increased incidence of moderate and difficult intubation (33/208 [16%] vs. 18/208 [9%]; P < 0.001), and need for adjuncts to direct laryngoscopy (40/208 [19%] vs. 21/208 [10%]; P = 0.002), compared with the operating room. Complications were more common during tracheal intubations in the intensive care unit (76/208; 37%) compared with the operating room (13/208; 6%; P < 0.001). CONCLUSIONS: Compared with the operating room, tracheal intubations in the intensive care unit were associated with worse intubation conditions and an increase of complications.

Impact of universal use of a hyperangulated videolaryngoscope as the first option for all intubations in the ICU: A prospective before-after study.

BACKGROUND: Tracheal intubation in ICU is associated with high incidence of difficult intubations. The study aimed to investigate whether the "universal" use of a hyperangulated videolaryngoscope would increase the frequency of "easy intubation" in ICU patients compared to direct laryngoscopy. METHODS: A prospective before-after study was conducted. The pre-interventional period (36 months) involved tracheal intubations using direct laryngoscopy as the first intubation option. In the interventional period (18 months) a hyperangulated videolaryngoscope was the first intubation option. The primary outcome was the percentage of patients with "easy intubation" defined as intubation on the first attempt and easy laryngoscopy (modified Cormack-Lehane glottic view of I-IIa). Secondary outcomes included difficult laryngoscopy, operator technical difficulty, and complications. RESULTS: We enrolled 407 patients, 273 in non-interventional period, and 134 in interventional period. Tracheal intubation in the interventional period was associated with higher incidence of "easy intubation" (92.5%) compared with the non-interventional period (75.8%); P < 0.001)). Glottic visualization improved in the interventional period, with a reduced incidence of difficult laryngoscopy (1.5% vs. 22.5%; P < 0.001). The proportion of first-success rate intubation was 92.5% in the interventional period, and 87.8% in the non-interventional period (P = 0.147). Moderate and severe technical difficulty of intubation reported decreased in the interventional period (6% vs. 17.6%; P < 0.001). There was no significant difference between both periods in the incidence of complications. CONCLUSION: "Universal" use of hyperangulated videolaryngoscopy for tracheal intubation in patients admitted in ICU improves the percentage of easy intubation compared to direct laryngoscopy.

Videolaryngoscope versus conventional technique for insertion of a transesophageal echocardiography probe in intubated ICU patients (VIDLARECO trial): A randomized clinical trial.

BACKGROUND: Transesophageal echocardiogram probe insertion in intubated critically ill patients can be difficult, leading to complications, such as gastric bleeding or lesions in the oropharyngeal mucosa. We hypothesised that the use of a videolaryngoscope would facilitate the first attempt at insertion of the transesophageal echocardiogram probe and would decrease the incidence of complications compared to the conventional insertion technique. METHODS: In this clinical trial, patients were randomly assigned the insertion of a transesophageal echocardiogram probe using a videolaryngoscope or conventional technique. The primary outcome was the successful transesophageal echocardiogram probe insertion on the first attempt. The secondary outcomes included total success rate, number of insertion attempts, and incidence of pharyngeal complications. RESULTS: A total of 100 intubated critically ill patients were enrolled. The success rate of transesophageal echocardiogram probe insertion on the first attempt was higher in the videolaryngoscope group than in the conventional group (90% vs. 58%; absolute difference, 32%; 95% CI 16%-48%; p < 0.001). The overall success rate was higher in the videolaryngoscope group than in the conventional group (100% vs. 72%; absolute difference, 28%; 95% CI 16%-40%; p < 0.001). The incidence of pharyngeal mucosal injury was smaller in the videolaryngoscope group than in the conventional group (14% vs. 52%; absolute difference, 38%; 95% CI 21%-55%; p < 0.001). CONCLUSIONS: Our study showed that in intubated critically ill patients required transesophageal echocardiogram, the use of videolaryngoscope resulted in higher successful insertion on the first attempt with lower rate of complications when compared with the conventional insertion technique. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04980976.

Effect of early vs. delayed extubation on functional outcome among patients with acute ischemic stroke treated with endovascular thrombectomy under general anesthesia: the prospective, randomized controlled EDESTROKE trial study protocol.

BACKGROUND: Recent meta-analyses and randomized studies have shown that among patients with acute ischemic stroke undergoing endovascular thrombectomy, general anesthesia with mechanical ventilation is associated with better functional status compared to local anesthesia and sedation, and they recommend its use. But once the procedure is completed, when is the optimal moment for extubation? Currently, there are no guidelines recommending the optimal moment for extubation. Prolonged mechanical ventilation time could potentially be linked to increased complications such as pneumonia or disturbances in cerebral blood flow due to the vasodilatation produced by most anesthetic drugs. However, premature extubation in a patient who has suffered a stroke could led to complications such as agitation, disorientation, abolished reflexes, sudden fluctuations in blood pressure, alterations in cerebral blood flow, respiratory distress, bronchial aspiration, and the need for reintubation. We therefore designed a randomized study hypothesizing that early compared with delayed extubation is associated with a better functional outcome 3 months after endovascular thrombectomy treatment under general anesthesia for acute ischemic stroke. METHODS: This investigator-initiated, single-center, prospective, parallel, evaluated blinded, superiority, randomized controlled trial will include 178 patients with a proximal occlusion of the anterior circulation treated with successful endovascular thrombectomy (TICI 2b-3) under general anesthesia. Patients will be randomly allocated to receive early (< 6 h) or delayed (6-12 h) extubation after the procedure. The primary outcome measure is functional independence (mRS of 0-2) at 90 days, measured with the modified Rankin Score (mRS), ranging from 0 (no symptoms) to 6 (death). DISCUSSION: This will be the first trial to compare the effect of mechanical ventilation duration (early vs delayed extubation) after satisfactory endovascular thrombectomy for acute ischemic stroke under general anesthesia. TRIAL REGISTRATION: The study protocol was approved April 11, 2023, by the by the Santiago-Lugo Research Ethics Committee (CEI-SL), number 2023/127, and was registered into the clinicaltrials.gov clinical trials registry with No. NCT05847309. Informed consent is required. Participant recruitment begins on April 18, 2023. The results will be submitted for publication in a peer-reviewed journal and presented at one or more scientific conferences.

Effects of sevoflurane postconditioning on cell death, inflammation and TLR expression in human endothelial cells exposed to LPS.

BACKGROUND: Sevoflurane is an anesthetic agent which also participates in protective mechanisms in sepsis, likely due to anti-inflammatory properties. A key tissue in sepsis is the endothelium, which expresses TLR2 and TLR4 receptors, known regulators of inflammatory mechanisms and potential therapeutic targets for this pathology. In this context, we explored the effect of sevoflurane postconditioning in an in vitro sepsis model. METHODS: Primary cultures of human umbilical vein endothelial cells were used for two different experiments. In the first set, cultures were placed in an airtight incubation chamber and exposed to different concentrations of sevoflurane (0,1,3 or 7% vol,) for 1 hour. In the second set, lipopolysaccharide from Escherichia coli 0111:B4 (1 µg/mL) was added to culture medium for 3 hours and cells were subsequently exposed to sevoflurane (0,1,3 or 7% vol,) for 1 hour as explained before. In both cases, cell viability was measured by MTT and Trypan blue assays, TLR2 and TLR4 expression were analyzed by flow cytometry, and TNFα and IL-6 levels were quantified in cell culture media by an immunoassay immediately after exposure, at 6 and 24 hours. RESULTS: Exposure to 3% sevoflurane decreased TLR2 at 24 hours and TLR4 at 6 and 24 hours (both p<0.05), whereas exposure to 7% decreased TLR4 expression at 6 hours (p<0.05). Both 3 and 7% sevoflurane decreased TNF-α and IL-6 levels at 24 hours (both p<0.05). In LPS-stimulated cultures, exposure to 3% sevoflurane was cytoprotective at 6 and 24 hours (p<0.05) compared with control, and decreased TLR2 and TLR4 expression at 24 hours (p<0.05); whereas 7% decreased TLR4 expression at 24 hours (p<0.05). Both 3% and 7% sevoflurane decreased TNF-α and IL-6 levels at 24 hours (both p<0.05). CONCLUSIONS: Postconditioning with the halogenated anesthetic agent sevoflurane after LPS stimulation shows a cytoprotective effect in an in vitro model, decreasing cell death and reducing TLR2 and TLR4 expression as well as levels of the inflammatory mediators TNF-α and IL-6 in human endothelial cells.

Development of prognostic models to estimate the probability of lung injury one year after COVID-19-related hospitalization-a prospective study.

Background: Long-term effects of severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) infection still under study. The objectives of this study were to identify persistent pulmonary lesions 1 year after coronavirus disease 2019 (COVID-19) hospitalization and assess whether it is possible to estimate the probability that a patient develops these complications in the future. Methods: A prospective study of ≥18 years old patients hospitalized for SARS-COV-2 infection who develop persistent respiratory symptoms, lung function abnormalities or have radiological findings 6-8 weeks after hospital discharge. Logistic regression models were used to identify prognostic factors associated with a higher risk of developing respiratory problems. Models performance was assessed in terms of calibration and discrimination. Results: A total of 233 patients [median age 66 years [interquartile range (IQR): 56, 74]; 138 (59.2%) male] were categorized into two groups based on whether they stayed in the critical care unit (79 cases) or not (154). At the end of follow-up, 179 patients (76.8%) developed persistent respiratory symptoms, and 22 patients (9.4%) showed radiological fibrotic lesions with pulmonary function abnormalities (post-COVID-19 fibrotic pulmonary lesions). Our prognostic models created to predict persistent respiratory symptoms [post-COVID-19 functional status at initial visit (the higher the score, the higher the risk), and history of bronchial asthma] and post-COVID-19 fibrotic pulmonary lesions [female; FVC% (the higher the FVC%, the lower the probability); and critical care unit stay] one year after infection showed good (AUC 0.857; 95% CI: 0.799-0.915) and excellent performance (AUC 0.901; 95% CI: 0.837-0.964), respectively. Conclusions: Constructed models show good performance in identifying patients at risk of developing lung injury one year after COVID-19-related hospitalization.

Critical patients COVID-19 has changed the management and outcomes in the ICU after 1 year of the pandemic? A multicenter, prospective, observational study.

OBJECTIVE: To compare the clinical characteristics, treatments, and evolution of critical patients with COVID-19 pneumonia treated in Intensive Care Units (ICU) after one year of pandemic. METHODOLOGY: Multicenter, prospective study, which included critical COVID-19 patients in 9 ICUs in northwestern Spain. The clinical characteristics, treatments, and evolution of patients admitted to the ICU during the months of March-April 2020 (period 1) were compared with patients admitted in January-February 2021 (period 2). RESULTS: 337 patients were included (98 in period 1 and 239 in period 2). In period 2, fewer patients required invasive mechanical ventilation (IMV) (65% vs 84%, p < 0.001), using high-flow nasal cannulas (CNAF) more frequently (70% vs 7%, p < 0.001), ventilation non-invasive mechanical (NIMV) (40% vs 14%, p < 0.001), corticosteroids (100% vs 96%, p = 0.007) and prone position in both awake (42% vs 28%, p = 0.012), and intubated patients (67% vs 54%, p = 0.034). The days of IMV, ICU stay and hospital stay were lower in period 2. Mortality was similar in the two periods studied (16% vs 17%). CONCLUSIONS: After 1 year of pandemic, we observed that in patients admitted to the ICU, CNAF, NIMV, use of the prone position, and corticosteroids have been used more frequently, reducing the number of patients in IMV, and the length of stay in the ICU and hospital stay. Mortality was similar in the two study periods.

Comparison of continuous infusion versus automated bolus for postoperative patient-controlled analgesia with popliteal sciatic nerve catheters.

BACKGROUND: This investigation was designed to compare a new methodology of automated regular bolus with a continuous infusion of local anesthetic for continuous popliteal sciatic block; both regimens were combined with patient-controlled analgesia (PCA). METHODS: Fifty patients undergoing hallux valgus repair were randomly allocated to receive an infusion of 0.125% levobupivacaine administered through a popliteal catheter as an automated regular bolus (n = 25) or as a continuous infusion (n = 25), both combined with PCA. Postoperative pain scores, incremental doses delivered by the PCA, local anesthetic consumed per hour, and the need for rescue tramadol analgesia were recorded. RESULTS: Both dosing regimens provided similar postoperative analgesia. Consumption of local anesthetic (5.14 ml/h, 5-5.75 ml/h) and dose request from the PCA (1, 0-5.4) was lower in the automated bolus group as compared to the continuous infusion group (5.9 ml/h, 5.05-7.8 ml/h; doses by PCA: 6.5, 0-20.5; P < 0.05). The need for rescue tramadol was similar in the two groups. CONCLUSION: In continuous popliteal sciatic block, local anesthetic administered as an automated regular bolus in conjunction with PCA provided similar pain relief as a continuous infusion technique combined with PCA; however, the new dosing regimen reduced the need for additional PCA and the overall consumption of local anesthetic.