The impact of ultrasound-guided erector spinae plane block on hemodynamic stability and postoperative pain in patients undergoing modified radical mastectomy for breast cancer.

OBJECTIVE: Breast cancer, a prevalent global malignancy in women, necessitates a comprehensive treatment approach, with surgery playing a crucial role. Severe acute pain is common post-radical breast cancer surgery, emphasizing the significance of hemodynamic stability and postoperative pain control for optimal outcomes. This study evaluates the impact of ultrasound-guided erector spinae plane block (ESPB) on these parameters in ASA scores 1-2 patients undergoing modified radical breast cancer surgery with general anesthesia. PATIENTS AND METHODS: Forty-eight patients were divided into two groups: a general anesthesia group, with erector spinae plane block (GA+ESPB), and a control group receiving only general anesthesia (GA). Hemodynamic parameters were continuously monitored, and postoperative pain was assessed using the visual analog scale (VAS) at various time points. RESULTS: Ultrasound-guided ESPB effectively maintained hemodynamic stability and reduced postoperative pain in breast cancer surgery patients. Statistically significant differences were observed in heart rate, systolic and diastolic blood pressure, and mean arterial pressure between the GA and GA+ESPB groups at multiple time points (p < 0.05). VAS scores showed a significant interaction time*group (p < 0.001), with consistent differences between the groups at all time points (p ≤ 0.001). CONCLUSIONS: Ultrasound-guided ESPB application proved effective in preserving hemodynamic stability and managing postoperative pain in modified radical breast cancer surgery. The technique demonstrates promise in minimizing complications related to hemodynamic variations and postoperative pain, contributing to a comprehensive approach to breast cancer surgical treatment.

Prognostic factors of intraoperative accidental extubation during laryngeal surgeries.

Background: Head and neck surgery is considered high-risk for difficult intubation and accidental extubation. Laryngomicroscopy implies surgical manipulations at the level of the vocal cords. Also, this type of surgery demands a particular position for the patient during the whole surgical intervention. All of this makes accidental extubation even more possible. Methods: We included a total of 100 patients scheduled for laryngomicroscopy in the study. We have assessed patients' general and clinical data and provided necessary measurements. After the intubation, we documented the depth of the endotracheal tube at the level of the upper incisors and repeated the measurement after the surgical intervention. We recorded all possible difficulties encountered by the surgeon. Results: We found a significantly more frequent tube dislocation in patients from the difficult intubation group, with χ2 =6.632, p =0.010. Inter-incisor gap (IIG) and modified Mallampati score showed statistical significance regarding tube dislocation, with p values of 0.002 and 0.047, respectively. There was statistical significance between tube dislocation and difficulties experienced by surgeons, with χ2 =13.504 and p =0.001. According to the area under the curve (AUC) at the Receiver operating characteristic (ROC) curve, the cut-off value for significant tube dislocation was 1.15 cm. When we divided the enrolled patients into two groups, below and above the cut-off value, the IIG maintained statistical significance with a cut-off value of 5.25 cm. Conclusions: Modified Mallampati score and IIG are considered valuable parameters for rapid preoperative risk assessment of possible accidental extubation. The final depth of the endotracheal tube should be about two cm deeper than necessary, as long as there is adequate ventilation on both sides of the lungs. Difficult intubation undoubtedly represents a risk for accidental extubation occurrence. HIPPOKRATIA 2023, 27 (4):141-147.

Interplay of model ingredients affecting aggregate shape plasticity in diffusion-limited aggregation.

We analyze the combined effect of three ingredients of an aggregation model--surface tension, particle flow and particle source--representing typical characteristics of many aggregation growth processes in nature. Through extensive numerical experiments and for different underlying lattice structures we demonstrate that the location of incoming particles and their preferential direction of flow can significantly affect the resulting general shape of the aggregate, while the surface tension controls the surface roughness. Combining all three ingredients increases the aggregate shape plasticity, yielding a wider spectrum of shapes as compared to earlier works that analyzed these ingredients separately. Our results indicate that the considered combination of effects is fundamental for modeling the polymorphic growth of a wide variety of structures in confined geometries and/or in the presence of external fields, such as rocks, crystals, corals, and biominerals.

Fractal analysis of retinal vessel patterns in ophthalmically normal dogs.

OBJECTIVE: To study the applicability of the fractal dimension as a parameter for describing retinal vessel patterns in ophthalmically normal dogs. PROCEDURES: The following strategy was adopted: (i) development of an experimental procedure to obtain digitalized photographs of the fundus; (ii) development of software to segment retinal vessel images and calculate the box-counting and radius of gyration fractal dimensions of the retinal vessels and diffusion-limited aggregation (DLA), a process with similar characteristics to retinal vessel morphology, and (iii) establishment of a standard curve for the fractal dimensions of segmented vessels. RESULTS: Digitalized photographs of the fundus showed an adequate contrast between the vessels and the rest of the fundus for numerical analysis. The software developed produced a binary image of the retinal vessels permitting calculation of the fractal dimension. The mean values of the fractal dimensions calculated by the methods of box-counting and radius of gyration for the DLA were significantly different (t = -40.33, P approximately 0). The radius of gyration method was found to be more suitable for documenting the dimension of the DLA and, consequently, of the dog's retinal vessels. CONCLUSION: This methodology may be useful to differentiate between normal and pathologic states of canine retinal vascularization.

Can a patient be successfully prepared for pheochromocytoma surgery in three days? A case report.

The case of a patient who insisted on urgent surgical removal of a pheochromocytoma is presented. Rapid preparation started with continuous infusion of urapidil 3 days before surgery. On the evening before the operation, an additional infusion of magnesium sulphate was started. The target of preoperative optimization was to maintain blood pressure <140/90 mm Hg and heart rate <100 beats min(-l). Anesthesia was induced with fentanyl, propofol and rocuronium and maintained with sevoflurane in 100% oxygen and continuous infusion of fentanyl. Hypertensive events were treated by continuous infusions of urapidil and magnesium sulphate. Just before tumor resection, additional boluses of urapidil and MgSO4 were administered; both fentanyl infusion and end tidal concentration of sevoflurane were increased. Blood pressure was well maintained through the anesthesia; no transient periods of hypotension after tumor removal were observed. The patient's peroperative course was uneventful. He was discharged home without antihypertensive medication on the 5th postoperative day. This case demonstrates that with urapidil and magnesium sulphate administration rapid preparation for pheochromocytoma resection can be successfully achieved within 3 days.