BMC Anesthesiology最新文献

Background: Accurate drug delivery in intensive care depends on precise and reliable preparation of intravenous solutions. Manual preparation is prone to error, and fluctuations in the delivery of vasoactive agents such as noradrenaline can cause haemodynamic volatility, leading to direct patient harm or being misinterpreted as instability and prompting unnecessary interventions. This study evaluated how different mixing techniques affect the homogeneity of noradrenaline solutions in 50 mL syringes to identify a safe preparation method for clinical use.

Methods: Six preparation methods, combining two target concentrations and three mixing techniques - no mixing; a single end-over-end syringe inversion; and inversion after aspiration of 5 mL air (the "Bubble-Flip") - were tested in a simulated syringe pump infusion experiment, with a pre-manufactured noradrenaline solution as reference. Each method was tested in five replicates. To illustrate three-dimensional concentration heterogeneity, additional syringes were flash-frozen in liquid nitrogen (four replicates each for two methods). In total, 38 experiments were performed. Noradrenaline concentrations were quantified by high-performance liquid chromatography.

Results: Mixing technique had a marked impact on solution homogeneity. The highest method-level variability (as coefficients of variation) were 30.7 % with no mixing and 12.2 % with a syringe inversion without air. Within-syringe variability ranged overall from 0.61 % to 39.9 %, with the highest values recorded for no mixing (39.0 %, 20.1 %) and inversion without air (14.8 %). By contrast, the Bubble-Flip method and the pre-mixed solution both achieved overall variability ≤2 %, within-syringe variability consistently < 5 %, and no samples deviated more than ±15 % from target. Three-dimensional reconstructions confirmed complex inhomogeneities with pronounced local spikes and drops, highlighting the risks of inadequate mixing.

Conclusions: Commercial pre-mixed products guarantee homogeneity but are costly. Comparable safety and consistency can be achieved with the Bubble-Flip method - a simple syringe inversion in the presence of 5 mL air. In contrast, manual preparation without proper mixing produced unsafe variability. These findings support the adoption of standardised mixing techniques to ensure reliable drug delivery and patient safety, with principles likely generalisable to other intravenously administered drugs requiring dilution.

Background: Microscopic polyangiitis (MPA) is a rare disease characterized by systemic vasculitis. However, perioperative endobronchial haemorrhage in these patients is not well-documented in medical literature.

Case presentation: We present the case of a 62-year-old woman with MPA who developed massive airway bleeding during thoracoscopic mitral valve replacement. The haemorrhage was successfully managed with bronchoscopic localization and bronchial artery embolization, which led to a rapid recovery.

Conclusion: This case increases the awareness of endobronchial haemorrhage in patients with MPA and underscores the critical role of a prepared, multidisciplinary team in achieving a successful outcome.

Background: This study aimed to evaluate the analgesic efficacy and safety of rectally administered diclofenac sodium suppositories during the perioperative period of pediatric circumcision using a disposable circumcision suture device (DCSD), and to provide guidance on their safe and effective use in pediatric practice.

Methods: In this prospective randomized controlled trial, 140 boys aged 7-12 years undergoing DCSD circumcision were randomly assigned to either the experimental group (n = 70; rectal diclofenac sodium, 1 mg/kg) or the control group (n = 70; oral ibuprofen, 10 mg/kg). All patients received local penile root block anesthesia with lidocaine. Pain was assessed using the Visual Analog Scale (VAS) by trained nurses blinded to group allocation, with parental assistance to minimize bias. Rescue analgesia use, adverse events, and postoperative sleep quality were also recorded.

Results: Reductions in VAS scores at scheduled time points did not differ significantly between groups, indicating comparable short-term analgesic efficacy. However, the diclofenac group required fewer rescue interventions, experienced a lower incidence of adverse events (10.0% vs. 30.0%), and demonstrated better postoperative sleep quality. Administration before dressing changes also improved patient cooperation.

Conclusion: Rectal diclofenac sodium suppositories are an effective and well-tolerated option for perioperative analgesia in pediatric circumcision using DCSD, providing improved comfort, sleep quality, and caregiver satisfaction compared to oral ibuprofen. However, due to the study's single-center design, short follow-up period, and the use of different NSAIDs between groups, the results should be interpreted with caution. Larger multicenter trials are necessary to confirm these findings and inform broader clinical application.

Trial registration: (TCTR20250513005) [Registered on 13/05/2025]. This trial is registered with the Thailand Clinical Trials Registry https//www.thaiclinicaltrials.org/ .

Introduction: Perioperative shivering (POS) is a common complication of spinal anesthesia (SA) during cesarean section (C/S), with incidence rates ranging from 36% to 85%. This study explored the association between third-trimester body mass index (BMI) and POS in women undergoing elective C/S under SA.

Materials and methods: In this prospective cohort study, 180 pregnant women scheduled for elective C/S were categorized into three BMI groups: normal (18.5-24.9 kg/m²), overweight (25-29.9 kg/m²), and obese (≥ 30 kg/m²). Shivering severity (Crossley and Mahajan scale), complications, and treatment needs were assessed every 15 min for 2 h post-SA.

Results: Participants had a mean age of 28.6 ± 5.8 years. Higher BMI was significantly associated with reduced shivering incidence from 30 min onward across multiple time points (P < 0.00833, Bonferroni-adjusted). At 30 min post-SA, obese and overweight women exhibited lower shivering rates than those with normal BMI (P < 0.001). After 60 min, severe shivering (grades 3-4) occurred in > 55% of normal-BMI women versus 15.8% of obese women (P < 0.001). Complications were less frequent in obese and overweight groups (P < 0.001), with 43% and 50% requiring no treatment, respectively, compared to 6.8% in the normal-BMI group (P < 0.001). Adjusted odds ratios confirmed a protective effect of higher BMI especially beyond 30 min post-intervention for postoperative shivering (e.g., obese: aOR = 0.13, 95% CI: 0.03-0.51, P = 0.003 at 30 min).

Conclusion: Elevated third-trimester BMI is linked to reduced POS incidence, severity, and complications, suggesting a protective role. Clinicians should prioritize shivering prevention strategies for women with normal BMI during C/S.

Background: Passive range of motion (PROM) is a common early mobilization technique in intensive care, especially for sedated, mechanically ventilated patients. This study aimed to evaluate the effect of early PROM on oxygen consumption (VO₂) and carbon dioxide production (VCO₂) in mechanically ventilated critically ill adults.

Methods: A prospective observational cohort study was conducted in the tertiary ICU of a university hospital between May and September 2023. PROM was initiated within 24-48 hours of admission in hemodynamically stable, sedated patients (RASS: -2 to -4). A physiotherapist performed a standardized 10-minute PROM protocol. VO₂ and VCO₂ were measured via indirect calorimetry before, during, and after the intervention. Statistical analyses were conducted using a repeated-measures ANOVA, with the average level before and after the measurement, as well as the peak level of VCO₂ during the intervention. Cardiovascular parameters were also recorded.

Results: Twenty-three patients were included. PROM exercises showed a significant quadratic trend in VCO₂; F = 6.686, p = 0.017 and a borderline quadratic trend in VO₂ (F = 4.320, p = 0.050). Heart rate decreased significantly compared to baseline (P = 0.043). No significant change in blood pressure levels was observed.

Conclusion: Early PROM exercises in sedated, mechanically ventilated ICU patients induced a quadratic trend in VCO₂ and VO₂, indicating a temporary and reversible metabolic response. PROM does not cause any hemodynamic instability. It accelerates the elimination of metabolic waste and can be used as part of early rehabilitation protocols.

Background: This randomized trial aimed to determine whether achievement of individualized blood pressure targets through norepinephrine administration can mitigate acute kidney injury (AKI) and reduce urine concentration, which serves as a surrogate marker for fluid retention, in older patients undergoing major abdominal surgery.

Methods: This study included 166 patients aged 55-80 years who were scheduled to undergo gastrectomy or colorectal cancer resection. They were randomly assigned to the individualized care group, in which systolic blood pressure or mean arterial pressure was maintained within ± 10% and ± 20% of baseline, respectively, using norepinephrine; or to the usual care group, in which mean arterial pressure was maintained at ≥ 65 mmHg without individualized titration. Individuals in both groups underwent continuous arterial monitoring and goal-directed fluid therapy. AKI was diagnosed based on the Kidney Disease: Improving Global Outcomes criteria. Further, renal injury was assessed based on serum neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule-1 (KIM-1) levels. Urine concentration scores were calculated from the urine parameters.

Results: AKI occurred in 13.5% and 14.3% of patients in the individualized and usual care groups, respectively. Patients in the usual care group experienced significant intraoperative fluctuations in mean arterial pressure. Norepinephrine was administered to 80.9% and 17.1% of patients in the individualized and usual care groups, respectively. Compared with the usual care group, the individualized care group demonstrated reduced NGAL levels and KIM-1 levels at the end of surgery and on postoperative day 2, and lower urine concentration scores at the end of surgery and on postoperative day 1.

Conclusion: Individualized blood pressure management using norepinephrine mitigated kidney damage, as indicated by elevated biomarkers, and decreased urine concentration, a surrogate indicator of fluid retention. However, it did not significantly reduce the incidence of AKI.

Trial registration: This trial was registered in the Chinese Clinical Trial Registry (ChiCTR2100049843) on August 10, 2021 ( https://www.chictr.org.cn/ ).

Background: Intrapartum cesarean section (CS) after epidural labour analgesia (ELA) is usually managed by catheter top-up, yet some centres prefer repeat spinal anaesthesia (SA) for speed and density of block. The failure rate of this strategy and its dose-response relationship with prior epidural drug exposure remain uncertain. This retrospective cohort study aimed to determine the incidence and risk factors of failed repeat SA in parturients undergoing intrapartum CS after receiving ELA.

Methods: We reviewed all parturients who received ELA and subsequently underwent intrapartum CS at Peking University International Hospital (Jan 2024-May 2025). Among 167 eligible women, 102 received repeat SA while 64 received epidural top-up, one received general anaesthesia (GA). The primary outcome was failed repeat SA, defined as inadequate surgical block before skin incision requiring re-puncture, epidural rescue or conversion to GA. Multivariable logistic regression was used to identify independent risk factors of failed repeat SA.

Results: Eighteen of 102 repeat SA cases failed (17.6%; 95% CI 11.6%-26.1%), with 9 requiring conversion to GA (8.8%). No high or total spinal block was observed. The only independent predictor of failure was the total volume of epidural solution administered during labour (adjusted OR 1.020 per 1 ml increment, 95% CI 1.004-1.037, p = 0.016). Obesity, clinician top-ups were not significant in the adjusted model.

Conclusions: Repeat SA following ELA carries a failure rate that exceeds accepted thresholds when cumulative epidural volume is high. The cumulative epidural volume is a readily quantifiable variable that can be integrated into risk-assessment algorithms. Prospective multicentre studies are warranted to validate this relationship and to test ancillary bedside measures (glucose reagent strips, pH testing or ultrasound) for confirming true subarachnoid placement before intrathecal injection.