Search published articles


Showing 4 results for Hemodynamics
The effects of the menstrual cycle on the hemodynamic response to laryngoscopy and tracheal intubation
Zahid Hussain Khan , Mojgan Rahimi , Pooya Kalani , Batool Ghorbani ,
Volume 72, Issue 4 (7-2014)
Abstract
Background: Hormonal, physical, and psychological fluctuations occur during the menstrual cycle. Previous studies have shown that hormonal changes during the normal menstrual cycle affect anesthesia and analgesia. The limitation of previous studies are that they did not measure luteal hormone (LH), Follicular stimulating hormone (FSH), estradiol, progesterone and cortisol levels. Our goal was to find more suitable conditions in menstrual periods for intubation of patient. Methods: American Society of Anesthesiologists physical status I patients, 16 to 40 years, undergoing general anesthesia for elective surgery were enrolled in this study and conducted at Imam Khomeini Medical Center in 2013. The patients were assigned into two groups according to the phase of their menstrual cycle. Levels of sex hormones and hemodynamic variables were recorded for all the patients and statistical analysis performed. Results: In 77 patients, 38 women were in the luteal phase (49.4%) and 39 women were in the follicular phase (50.6%). All tracheal intubations were successful on the first attempt with a mean duration of 2558±5.07 and 25.84±5.32 seconds in groups F and L, respectively (P=0.489). None of the patients were excluded for long tracheal intubation time. Systolic blood pressure after intubation in the follicular phase (138.4±20 mm Hg) was significantly higher vs. the luteal phase (127.7±18 mm Hg) (P<0.01), as well as the women’s heart rate after intubation in the luteal phase (90.7±12 beats per minute), was significantly higher than in the follicular phase (85.3±11 beats per minute) (P=0.05). Heart rate was higher in the luteal group than the follicular group thus the women’s heart rate after intubation in the luteal phase (90.7±12 bpm) was significantly greater than the follicular phase (85.3±11 bpm) (P=0.05). Conclusion: Reviewing and comparing the results show that elective surgeries are bet-ter to be done in the luteal phase because of stable hemodynamic conditions.
A patient-specific study of blood flow in a cerebral aneurysm using medical images
Reza Abdollahi , Bahman Vahidi , Mohammad Karimi ,
Volume 77, Issue 9 (12-2019)
Abstract
Background: Cerebral aneurysm disease causes intracranial hemorrhage by rupturing, which can eventually, lead to organ failure or death. For this reason, it is important to anticipate the reasons for rupturing of a cerebral aneurysm from biomechanical point of view. Investigating this disease may even help the physicians to find treatments and predict the patient’s situation. This research was conducted to understand risks of development and rupture of a patient-specific cerebral aneurysm.
Methods: In a computational simulation, fluid-structure interaction method has been used for a patient-specific case. Also, considering the speed of the systole as the initial condition of the problem, the blood fluid domain has been solved in three types of fluid mathematical models (Newtonian, non-Newtonian Carreau, and non-Newtonian power-law). Then, the pressure results on the wall have been transmitted to ANSYS software, version 15.0 (ANSYS Inc., Canonsburg, PA, USA) and the structure has been solved based on three material models (linear elastic, hyperplastic Neo-Hookean and hyperplastic Mooney-Rivlin, with 5 parameters). The study was done in University of Tehran, Iran, from October 2016 to September 2018.
Results: Shear stress, pressure, flow velocity, wall displacement and von-Mises stress have been extracted from the simulations. The average wall displacement of the aneurysm was 1.8 mm. Also, no significant difference was found in the amount of arterial wall displacement, with constant wall material model and different blood models. However, a significant difference has been observed in the case of considering constant blood model and different wall material models in the value of displacement.
Conclusion: With regard to the amount of displacement of the aneurysm wall in this particular patient, with the geometry and location of the specific aneurysm, the brain nerves 3 and 6 were under stress and exposed to damage. The minimum shear stress was in the aneurysm neck, which stimulates the endothelial cells in the area of aneurysm. In addition, the blood model didn’t had a significant effect on the displacement calculations, while the wall material model played a more decisive role.

The effect of auditory sensory stimulation with familiar voice on recovery from anesthesia in patients undergoing rhinoplasty
Mohammadhossein Dehghani , Seyedmohammadreza Niktabar , Amirreza Samei, Shamsodin Mohammadi,
Volume 79, Issue 1 (4-2021)
Abstract
Background: Anesthesia duration can play a significant role in post-operative complications. Therefore, the present study investigated the effect of auditory sensory stimulation with a familiar voice on anesthesia return in patients undergoing rhinoplasty.
Methods: This study was performed on 80 patients who were candidates for rhinoplasty surgery in Yazd Trauma and Burn Hospital from September-2018 to October-2019. The patients were randomly divided into two groups of 40: control and intervention. For patients in the control group, routine nursing care was performed after entering the recovery room. In addition to routine care, the patients in the intervention group were stimulated with a 15-minute pre-recorded audio. Patients' hemodynamic parameters were recorded before and after hearing stimulation. Also, the return time of the patient from anesthesia was recorded. Finally, the collected data were entered into SPSS software (Ver. 22) and analyzed using an independent sample t-test and Repeated mesasure ANOVA.
Results: The results of this study showed that from the fifth minute after auditory sensory stimulation, the mean arterial pressure (MAP) in the intervention group was significantly higher than the control group (P<0.05). So that MAP in recovery (as the last follow-up) in the intervention group with a mean of 86.85±4.11 mmHg was significantly higher than the control group with a mean of 81.88±6.68 mmHg (P<0.001). Besides, the duration of recovery from anesthesia in the intervention group was significantly less than the control group (mean time: 24.05±3.39 min vs. 34.70±70.73 min; P<0.001). Finally, nausea was observed in only 7.5% of patients in the control group and agitation was reported in 5% of the control group and 5% of the intervention group (P>0.05).
Conclusion: According to the results, the use of auditory sensory stimuli with a familiar voice can significantly decrease the duration of recovery from anesthesia. Also, it plays a crucial role in changing the SBP, DBP, and MAP of these patients to normal levels.

Providing a model for predicting blood pressure fluctuations after induction of general anesthesia with data mining: a brief report
Monireh Hosseini, Zahra Manouchehri ,
Volume 79, Issue 12 (3-2022)
Abstract
Background: Fluctuations in blood pressure after induction of general anesthesia have played a significant role in complications of surgery. Therefore, the present study was performed by identifying the causes of blood pressure fluctuations after induction of anesthesia, predicting and preventing them.
Methods: For this study which is a retrospective cohort, data mining methods in the data set including the information related to 3150 patients who underwent anesthesia and surgery from April 2018 to September 2019 in Imam Khomeini Hospital in Kermanshah were used. The data set included patients aged 18 years and older (age range of 18 to 96) who underwent a general anesthesia induction test using Propofol and subsequently endotracheal intubation for non-cardiac surgery. If patients did not have intubation, data were missing, or patients underwent intubation after repeated trials, they got excluded. In total, 2640 patients were included in this analysis. Preoperative patient clinical information was collected from pre-anesthesia evaluation records. Intraoperative data were obtained from computer anesthesia records. This data from the patient monitoring system and the anesthesia machine was automatically stored in the anesthesia files, while drug doses and anesthesia techniques were recorded manually. The data were then pre-processed using SPSS software, version 26 (IBM SPSS, Armonk, NY, USA).
Results: In this study, 53 features of patients' records were used (The maximum number of features used in previous studies were 48 features, which compared to them, 5 new features were included in the study) for which a P-value was calculated. Finally, features with a P<0.05 (Indicates the level of significance of the variable) were selected. Then, three data mining algorithms, logistic regression, neural networks and decision tree (the most repetitive data mining algorithms based on previous studies) were used to predict blood pressure. Also, using the criteria of accuracy, precision, sensitivity and F function, the performance of three prediction algorithms in data mining was evaluated.
Conclusion: Six features with P<0.05 were selected that the logistic regression model was more accurate, which was presented as the final model for predicting increased blood pressure fluctuations with path coefficients.
 

Page 1 from 1     

© 2024 , Tehran University of Medical Sciences, CC BY-NC 4.0

Designed & Developed by : Yektaweb