Suicide left ventricle describes the development of dynamic intraventricular gradients after aortic valve replacement due to acute hemodynamic changes that happen after relieving the obstruction leading to hemodynamic collapse. This is a rare complication in transcatheter aortic valve replacement and is underreported in surgical aortic valve replacement (SAVR). We present the case of a male patient who presented with suicide left ventricle after SAVR.

OBJECTIVES: To explore the predictive factors for hemodynamically significant patent ductus arteriosus (hsPDA) in preterm infants and to construct a nomogram prediction model for hsPDA occurrence in this population. METHODS: A retrospective analysis was conducted on the clinical data of preterm infants with gestational age <32 weeks diagnosed with patent ductus arteriosus (PDA) who were delivered at Nanjing Women and Children's Healthcare Hospital from January 2020 to December 2022. The subjects were divided into an hsPDA group (52 cases) and a non-hsPDA group (176 cases) based on the presence of hsPDA. Univariate analysis and multivariate logistic regression analysis were performed to screen predictive variables regarding the general information of the infants at birth, maternal pregnancy and delivery conditions, and relevant indicators during hospitalization. A nomogram prediction model for hsPDA occurrence was constructed using R software in preterm infants. Internal validation was performed using the Bootstrap method. Finally, the predictive model was evaluated for calibration, discrimination ability, and clinical utility. RESULTS: Multivariate regression analysis showed that the ratio of the left atrium to aorta diameter (LA/AO), mode of delivery (vaginal), and duration of mechanical ventilation were independent predictive factors for hsPDA in preterm infants (P<0.05). Based on the results of univariate analysis and multivariate logistic regression analysis, variables used to construct the nomogram prediction model for hsPDA risk included: LA/AO ratio, mode of delivery (vaginal), duration of mechanical ventilation, 5-minute Apgar score, and the presence of neonatal respiratory distress syndrome requiring surfactant therapy. The area under the receiver operating characteristic curve for this model was 0.876 (95%CI: 0.824-0.927), and the calibrated curve was close to the ideal reference line, indicating good calibration. The Hosmer-Lemeshow test demonstrated that the model fit well, and the clinical decision curve was above the extreme curves. CONCLUSIONS The nomogram prediction model, constructed using five variables (LA/AO ratio, vaginal delivery, duration of mechanical ventilation, 5-minute Apgar score, and the presence of neonatal respiratory distress syndrome requiring surfactant therapy), has reference significance for predicting the occurrence of hsPDA in preterm infants and provides valuable guidance for the early clinical identification of hsPDA.
Humans ; Ductus Arteriosus, Patent/etiology* ; Nomograms ; Female ; Infant, Newborn ; Infant, Premature ; Retrospective Studies ; Male ; Hemodynamics ; Logistic Models ; Pregnancy

OBJECTIVES: To investigate the risk factors for the occurrence of cardiopulmonary dysfunction following ligation of hemodynamically significant patent ductus arteriosus (hsPDA) in preterm infants. METHODS: A retrospective collection of clinical data was conducted on preterm infants with a gestational age of <34 weeks who were admitted to the Maternal and Child Health Hospital of Hubei Province, Tongji Medical College, Huazhong University of Science and Technology from January 2018 to August 2024. These infants underwent hsPDA ligation after 1-2 courses of failed ibuprofen treatment. Based on the occurrence of blood pressure changes and oxygenation or ventilation failure postoperatively, the infants were divided into a cardiopulmonary dysfunction group (19 cases) and a non-cardiopulmonary dysfunction group (40 cases). Binary logistic regression analysis was performed to explore risk factors for postoperative cardiopulmonary dysfunction. RESULTS: Binary logistic regression analysis indicated that a faster average weight gain rate preoperatively and low levels of free triiodothyronine (FT₃) within one week before surgery were risk factors for cardiopulmonary dysfunction following hsPDA ligation (P<0.05). Receiver operating characteristic curve analysis showed that an average weight gain rate >11.45 g/(kg·d) and FT₃ levels <2.785 pmol/L within one week before surgery had predictive value for postoperative cardiopulmonary dysfunction (P<0.05). The combination of these two indicators provided the highest predictive value (P<0.05), with an area under the curve of 0.825, a sensitivity of 79%, and a specificity of 75%. CONCLUSIONS An average weight gain rate exceeding 11.45 g/(kg·d) and FT₃ levels below 2.785 pmol/L within one week before surgery are risk factors affecting cardiopulmonary function after hsPDA ligation. Preoperative assessment and intervention should be strengthened to reduce the risk of postoperative complications.
Humans ; Ductus Arteriosus, Patent/physiopathology* ; Risk Factors ; Female ; Infant, Newborn ; Male ; Retrospective Studies ; Infant, Premature ; Ligation/adverse effects* ; Hemodynamics ; Postoperative Complications/etiology* ; Logistic Models ; Lung Diseases/etiology*

Hemodynamic monitoring can reflect cardiac function and blood perfusion and is an indispensable monitoring method in clinical practice. Invasive hemodynamic monitoring methods represented by the thermodilution method are limited in their clinical application scope because they require vascular cannulation. Non-invasive hemodynamic monitoring has attracted extensive attention from medical companies and clinicians at home and abroad in recent years due to its advantages such as safety, non-invasiveness, continuous monitoring, simple operation, and low cost. This paper designs a non-invasive hemodynamic monitoring system based on the impedance cardiography, including hardware, algorithm, software design, and performance parameter evaluation. Among them, the hardware part mainly includes a differential high-frequency constant current source stimulation circuit, impedance cardiogram signal acquisition, and ECG signal acquisition circuit. Signal processing includes wave filtering, impedance cardiogram signal calibration, and ECG signal and impedance cardiogram signal feature point recognition. According to the collected impedance cardiogram and ECG signals, hemodynamic parameters such as heart rate (HR), stroke volume (SV), cardiac output (CO), stroke index (SI), cardiac index (CI), and cardiac contractility index (ICON) are calculated based on the Nyboer thoracic cylinder model. After testing, the key technical indicators of the system hardware are better than that of the relevant medical device standards. The system was used to collect impedance cardiogram and ECG signal data from 40 volunteers. The calculated HR, SV, and CO, three important hemodynamic indicators, were compared with the ICONCore non-invasive cardiac output monitor of OSYPKA Medical in Germany. Their Pearson correlation coefficients were 0.992 ( P<0.001), 0.948 ( P<0.001), and 0.933 ( P<0.001), respectively, verifying that the designed system has high accuracy and reliability.
Cardiography, Impedance/methods* ; Humans ; Hemodynamic Monitoring/methods* ; Equipment Design ; Signal Processing, Computer-Assisted ; Hemodynamics ; Algorithms ; Monitoring, Physiologic/methods* ; Electrocardiography

OBJECTIVES: The diagnostic value of ultrasonographic quantitative indicators of umbilical cord coiling, such as the umbilical coiling index (UCI) and pitch value, in identifying hypercoiling and predicting adverse pregnancy outcomes remains controversial. This study aims to evaluate the predictive value of UCI, pitch value, and the cerebroplacental ratio in pregnancies complicated by umbilical cord hypercoiling. METHODS: Pregnant women with densely coiled umbilical cords identified by routine obstetric ultrasound at Changsha Maternal and Child Health Hospital between November 2022 and November 2024 were enrolled. Complete clinical data, including UCI, pitch value, and cerebroplacental ratio (CPR), were collected. Pregnancy outcome scores were calculated, and newborns were categorized into the normal outcome group (n=177) and adverse outcome group (n=85), with the latter further subdivided into mild (n=51), moderate (n=19), and severe (n=15) subgroups. Differences in baseline data, UCI, pitch value, and incidence of CRP<1 were compared between groups and among subgroups. Correlations between UCI, pitch value, and adverse pregnancy outcomes were analyzed. Receiver operating characteristic (ROC) curve were used to assess the predictive performance of UCI, pitch value, CPR<1, and their combinations. RESULTS: Compared with the normal outcome group, the adverse outcome group had higher age, parity, parity, incidence of CPR<1, and UCI, while gestational age at delivery and pitch values were lower (all P<0.05). The incidence of obesity, gestational diabetes mellitus, and hypertensive disorders of pregnancy did not differ significantly between the 2 groups (all P>0.05). The normal outcome group showed lower UCI and higher pitch values than all 3 adverse outcome subgroups (all P<0.05), while differences among the 3 adverse subgroups were not significant (all P>0.05). UCI was positively correlated with adverse pregnancy outcomes (r_s=0.350, P<0.05), whereas pitch value was negatively correlated (r_s=-0.286, P<0.05). ROC curve analysis showed that the area under the curve (AUC) values for predicting adverse outcomes were 0.837 for UCI, 0.886 for pitch value, and 0.610 for CPR<1, with sensitivities of 77.6%, 82.4%, and 27.1% and specificities of 78.5%, 83.6%, and 94.9%, respectively. The combined UCI+CPR<1 and pitch value+CPR<1 models yielded AUCs of 0.841 and 0.886, with sensitivities of 78.8% and 81.2% and specificities of 78.5% and 84.2%, respectively. No significant differences were found between the AUCs of UCI and pitch value (P>0.05), but both outperformed CPR<1 alone (both P<0.001). The combined models showed no significant improvement over UCI or pitch value alone (both P>0.05), though both were superior to CPR<1 alone (both P<0.001). CONCLUSIONS Most umbilical cord hypercoiling cases had favorable outcomes, with UCI, pitch value, CPR<1 and their combinations demonstrating significant predictive value for adverse pregnancy outcomes.
Humans ; Female ; Pregnancy ; Pregnancy Outcome ; Adult ; Ultrasonography, Prenatal/methods* ; Umbilical Cord/diagnostic imaging* ; Hemodynamics ; Predictive Value of Tests ; Infant, Newborn ; ROC Curve

OBJECTIVE: To compare the clinical efficacy of acupuncture with Neiguan (PC6)-to-Waiguan (TE5) and esmolol on hemodynamics during anesthesia induction and postoperative nausea and vomiting. METHODS: A total of 100 patients undergoing elective laparoscopic hernia repair or gynecological surgery under general anesthesia were randomly divided into an acupuncture group (50 cases, 3 cases were eliminated) and an esmolol group (50 cases, 2 cases were eliminated). In the acupuncture group, before anesthesia induction, patients were applied to acupuncture with Neiguan (PC6)-to-Waiguan (TE5), and the needles were retained for 15 min on the right side and 30 min on the left side. Patients in the esmolol group were intravenously injected with 20 mg esmolol hydrochloride injection 5 min before anesthesia induction. The systolic blood pressure (SBP) and heart rate (HR) of the two groups were recorded at 5 min after entering the operating room (T₀), before anesthesia induction (T₁), after anesthesia induction (T₂), before tracheal intubation (T₃) and 1 min after tracheal intubation (T₄). The visual analogue scale (VAS) scores of pain and the incidence of nausea and vomiting in the two groups were observed at the time of entering postanesthesia care unit (PACU) (T₅), leaving PACU (T₆), 6 h after operation (T₇) and 24 h after operation (T₈). The dosage of anesthesia-related drugs in the two groups was counted. RESULTS: The SBP and HR of the two groups at T₂, T₃ and T₄ were lower than those at T₁ (P<0.05). SBP and HR at T₃ in the acupuncture group were higher than those in the esmolol group (P<0.05). Compared with the esmolol group, in the acupuncture group, the VAS scores of pain at T₆ and T₇ were decreased (P<0.05), the incidence of nausea and vomiting at T₇ and T₈ and the nausea and vomiting visual analogue scale (NVAS) scores were decreased (P<0.05). Compared with the esmolol group, the dosage of propofol in the acupuncture group was decreased (P<0.05). CONCLUSION Acupuncture with Neiguan (PC6)-to-Waiguan (TE5) can relieve hemodynamic fluctuations during anesthesia induction, reduce postoperative pain and nausea and vomiting, and reduce the dosage of propofol. The curative effect is better than that of esmolol.
Humans ; Female ; Adult ; Middle Aged ; Acupuncture Points ; Male ; Hemodynamics ; Propanolamines/administration & dosage* ; Postoperative Nausea and Vomiting/drug therapy* ; Young Adult ; Heart Rate ; Aged ; Blood Pressure ; Acupuncture Therapy

The purpose of the present study was to investigate the effects of resistance combined with aerobic chrono-exercise on the common carotid artery elasticity and hemodynamics. 24 healthy young men (21.96±0.43 years old) underwent a single acute resistance combined with aerobic exercise intervention at eight time periods (6, 8, 10, 12, 14, 16, 18, and 20 o'clock). The axial flow velocity and diameter waveforms of the common carotid artery were measured, and the hemodynamics were calculated using the classical hemodynamic theory before exercise, immediately after exercise, 10 min and 20 min after exercise. The results showed that during exercise recovery, systolic and mean pressures decreased more markedly after exercise at 8 o'clock (P < 0.05); At 20 min post-exercise, arterial stiffness index and pressure-strain elastic modulus after exercise at 6 o'clock were reduced compared with the resting state, but were significantly elevated after exercise at 20 o'clock (P < 0.05). Immediately after exercise, the pressure rise was higher after exercise at 6 o'clock and the mean wall shear stress was higher after exercise at 20 o'clock (P < 0.05). These results suggest that resistance combined with aerobic chrono-exercise produces different effects on common carotid artery hemodynamics in young men. A single acute session of resistance combined with aerobic exercise at 8 o'clock is more effective in lowering blood pressure. Exercise at 6 o'clock is beneficial to improve arterial elasticity but is not recommended for young male individuals with cardiovascular disease risks because of the excessive increase in blood pressure immediately after exercise. Exercise at 20 o'clock is more effective in improving wall shear stress but is accompanied by elevated arterial stiffness indices and pressure-strain elastic modulus. These results provide a scientific basis for healthy young men in choosing the time of exercise by exploring the common carotid artery elasticity and hemodynamic-related indices.
Humans ; Male ; Young Adult ; Exercise/physiology* ; Carotid Artery, Common/physiology* ; Hemodynamics/physiology* ; Vascular Stiffness/physiology* ; Elasticity ; Resistance Training ; Adult

OBJECTIVE: To observe the characteristics of changes in non-invasive hemodynamic parameters in neonates with septic shock so as to provide clinical reference for diagnosis and treatment. METHODS: A observational study was conducted. The neonates with sepsis complicated with septic shock or not admitted to neonatal intensive care unit (NICU) of the First Affiliated Hospital of Shantou University Medical College were enrolled as the study subjects, who were divided into preterm infant (< 37 weeks) and full-term infant (≥ 37 weeks) according to the gestational age. Healthy full-term infants and hemodynamically stable preterm infants transferring to NICU after birth were enrolled as controls. Electronic cardiometry (EC) was used to measure hemodynamic parameters, including heart rate (HR), mean arterial pressure (MAP), stroke volume (SV), stroke volume index (SVI), cardiac output (CO), cardiac index (CI), systemic vascular resistance (SVR) and systemic vascular resistance index (SVRI), before treatment in the septic shock group, at the time of diagnosis of sepsis in the sepsis without shock group, and before the discharge from the obstetric department or on the day of transferring to NICU in the control group. RESULTS: Finally, 113 neonates with complete data and parental consent for non-invasive hemodynamic monitoring were enrolled, including 32 cases in the septic shock group, 25 cases in the sepsis without shock group and 56 cases in the control group. In the septic shock group, there were 17 cases at the compensated stage and 15 cases at the decompensated stage. There were 21 full-term infants (20 cured or improved and 1 died) and 11 premature infants (7 cured or improved and 4 died), with the mortality of 15.62% (5/32). There were 18 full-term infants and 7 premature infants in the sepsis without shock group and all cured or improved without death. The control group included 28 full-term infants and 28 premature infants transferring to NICU after birth. Non-invasive hemodynamic parameter analysis showed that SV, SVI, CO and CI of full-term infants in the septic shock group were significantly lower than those in the sepsis without shock group and control group [SV (mL): 3.52±0.99 vs. 5.79±1.32, 5.22±1.02, SVI (mL/m²): 16.80 (15.05, 19.65) vs. 27.00 (22.00, 32.00), 27.00 (23.00, 29.75), CO (L/min): 0.52±0.17 vs. 0.80±0.14, 0.72±0.12, CI (mL×s^-1×m^-2): 40.00 (36.67, 49.18) vs. 62.51 (56.34, 70.85), 60.01 (53.34, 69.68), all P < 0.05], while SVR and SVRI were significantly higher than those in the sepsis without shock group and control group [SVR (kPa×s×L^-1): 773.46±291.96 vs. 524.17±84.76, 549.38±72.36, SVRI (kPa×s×L^-1×m^-2): 149.27±51.76 vs. 108.12±12.66, 107.81±11.87, all P < 0.05]. MAP, SV, SVI, CO and CI of preterm infants in the septic shock group were significantly lower than those in the control group [MAP (mmHg, 1 mmHg ≈ 0.133 kPa): 38.55±10.48 vs. 47.46±2.85, SV (mL): 2.45 (1.36, 3.58) vs. 3.96 (3.56, 4.49), SVI (mL/m²): 17.60 (14.20, 25.00) vs. 25.50 (24.00, 29.00), CO (L/min): 0.32 (0.24, 0.63) vs. 0.56 (0.49, 0.63), CI (mL×s^-1×m^-2): 40.01 (33.34, 53.34) vs. 61.68 (56.68, 63.35), all P < 0.05], while SVR and SVRI were similar to the control group [SVR (kPa×s×L^-1): 1 082.88±689.39 vs. 656.63±118.83, SVRI (kPa×s×L^-1×m^-2): 126.00±61.50 vs. 102.37±11.68, both P > 0.05]. Further analysis showed that SV, SVI and CI of neonates at the compensation stage in the septic shock group were significantly lower than those in the control group [SV (mL): 3.60±1.29 vs. 4.73±1.15, SVI (mL/m²): 19.20±8.33 vs. 26.34±3.91, CI (mL×s^-1×m^-2): 46.51±20.34 vs. 61.01±7.67, all P < 0.05], while MAP, SVR and SVRI were significantly higher than those in the control group [MAP (mmHg): 52.06±8.61 vs. 48.54±3.21, SVR (kPa×s×L^-1): 874.95±318.70 vs. 603.01±111.49, SVRI (kPa×s×L^-1×m^-2): 165.07±54.90 vs. 105.09±11.99, all P < 0.05]; MAP, SV, SVI, CO and CI of neonates at the decompensated stage in the septic shock group were significantly lower than those in the control group [MAP (mmHg): 35.13±6.08 vs. 48.54±3.21, SV (mL): 2.89±1.17 vs. 4.73±1.15, SVI (mL/m²): 18.50±4.99 vs. 26.34±3.91, CO (L/min): 0.41±0.19 vs. 0.65±0.15, CI (mL×s^-1×m^-2): 43.34±14.17 vs. 61.01±7.67, all P < 0.05], while SVR and SVRI were similar to the control group [SVR (kPa×s×L^-1): 885.49±628.04 vs. 603.01±111.49, SVRI (kPa×s×L^-1×m^-2): 114.29±43.54 vs. 105.09±11.99, both P > 0.05]. CONCLUSIONS Full-term infant with septic shock exhibit a low cardiac output, high vascular resistance hemodynamic pattern, while preterm infant with septic shock show low cardiac output and normal vascular resistance. At the compensated stage the hemodynamic change is low output and high resistance type, while at the decompensated stage it is low output and normal resistance type. Non-invasive hemodynamic monitoring can assist in the identification of neonatal septic shock and provide basis for clinical diagnosis and treatment.
Humans ; Shock, Septic/physiopathology* ; Infant, Newborn ; Hemodynamics ; Female ; Male ; Case-Control Studies ; Infant, Premature

OBJECTIVE: To investigate the effects of using different filters in continuous renal replacement therapy (CRRT) on the mortality, inflammatory mediator level and hemodynamics in patients with sepsis-associated acute kidney injury (SA-AKI). METHODS: A prospective study was conducted. The patients with SA-AKI undergoing first CRRT admitted to the critical care medicine department of General Hospital of Ningxia Medical University from August 2022 to October 2023 were enrolled as the study objects, and they were divided into observation group and control group by random number table method. All patients received routine treatment including anti-infection, optimized volume management and organ function support. On this basis, the observation group was treated with oXiris filter for CRRT, while the control group was treated with ordinary filter for CRRT, and the first treatment time was ≥ 36 hours. General data of the two groups were collected and compared. At the same time, the inflammatory indicators [high-sensitivity C-reactive protein (hs-CRP), procalcitonin (PCT), interleukin-6 (IL-6)], sequential organ failure assessment (SOFA) score, mean arterial pressure (MAP), blood lactic acid (Lac), noradrenaline dosage and other related indicators were collected before CRRT treatment and 24 hours and 48 hours after treatment, and the 7-day and 28-day mortality of patients were recorded. RESULTS: Finally, 65 patients were enrolled, including 30 in the observation group and 35 in the control group. There were no significant differences in baseline data including age, gender, acute kidney injury (AKI) stage and infection source between the two groups. The 7-day mortality of observation group was significantly lower than that of control group [16.7% (5/30) vs. 42.9% (15/35), P < 0.05]. There was no significant difference in 28-day mortality between the observation group and the control group [36.7% (11/30) vs. 54.3% (19/35), P > 0.05]. There were no significant differences in inflammation indicators, SOFA score, MAP, Lac and norepinephrine dosage before treatment between the two groups. After 24-hour and 48-hour treatment, the hemodynamics of the two groups were stable compared with before treatment, the inflammatory indicators, SOFA score, Lac and norepinephrine dosage were reduced to varying degrees, and MAP was significantly increased. In the observation group, hs-CRP, PCT, IL-6, SOFA score, MAP, and norepinephrine dosage showed statistical significance at 24 hours after treatment as compared with before treatment [hs-CRP (mg/L): 125.0 (105.0, 171.2) vs. 280.5 (213.2, 313.8), PCT (μg/L): 51.0 (20.0, 62.8) vs. 71.0 (10.8, 100.0), IL-6 (ng/L): 1 762.2 (300.8, 4 327.5) vs. 4 447.5 (630.4, 5 000.0), SOFA score: 13.0 (12.0, 14.0) vs. 16.0 (15.0, 17.0), MAP (mmHg, 1 mmHg ≈ 0.133 kPa): 79.00±12.87 vs. 65.20±11.70, norepinephrine dosage (μg×kg^-1×min^-1): 0.82±0.33 vs. 1.63±0.51, all P < 0.05]. In the control group, PCT and MAP showed statistical significance after 48 hours of treatment as compared with before treatment. Compared with the control group, hs-CRP, SOFA score and norepinephrine dosage after 48 hours of treatment in the observation group were significantly decreased [hs-CRP (mg/L): 87.2 (74.2, 126.0) vs. 157.0 (88.0, 200.0), SOFA score: 11.0 (10.0, 12.0) vs. 12.0 (10.0, 14.0), norepinephrine dosage (μg×kg^-1×min^-1): 0.51±0.37 vs. 0.81±0.58, all P < 0.05], MAP was significantly increased (mmHg: 82.00±8.71 vs. 77.77±7.80, P < 0.05). CONCLUSION In the treatment of CRRT, oXiris filter can reduce the short-term mortality of SA-AKI patients, lower inflammatory mediators levels and improve hemodynamics, showing therapeutic advantages over conventional filters.
Humans ; Acute Kidney Injury/etiology* ; Sepsis/therapy* ; Prospective Studies ; Interleukin-6 ; Continuous Renal Replacement Therapy/methods* ; C-Reactive Protein ; Male ; Female ; Middle Aged ; Hemodynamics ; Procalcitonin ; Aged

OBJECTIVE: To compare the effects of different chest compression rates (60-140 times/min) on hemodynamic parameters, return of spontaneous circulation (ROSC), resuscitation success, and survival in a porcine model of cardiac arrest (CA) followed by cardiopulmonary resuscitation (CPR). METHODS: Forty healthy male domestic pigs were randomly divided into five groups based on chest compression rate: 60, 80, 100, 120, and 140 times/min (n = 8). All animals underwent standard anesthesia and tracheal intubation. A catheter was inserted via the left femoral artery into the thoracic aorta to monitor aortic pressure (AOP), and another via the right external jugular vein into the right atrium to monitor right atrial pressure (RAP). In each group, animals were implanted with a stimulating electrode via the right external jugular vein to the endocardium, and ventricular fibrillation (VF) was induced by delivering alternating current stimulation, resulting in CA. After a 1-minute, manual chest compressions were performed at the assigned rate with a compression depth of 5 cm. The first defibrillation was delivered after 2 minutes of CPR. No epinephrine or other pharmacologic agents were administered during the entire resuscitation process. From 1 minute before VF induction to 10 minutes after ROSC, dynamic monitoring of AOP, coronary perfusion pressure (CPP), and partial pressure of end-tidal carbon dioxide (P_ETCO₂). Cortical ultrastructure was examined 24 hours post-ROSC using transmission electron microscopy. RESULTS: With increasing compression rates, both the total number of defibrillations and cumulative defibrillation energy significantly decreased, reaching their lowest levels in the 120 times/min group. The number of defibrillations decreased from (4.88±0.83) times in the 60 times/min group to (2.25±0.71) times in the 120 compressions/min group, and energy from (975.00±166.90)J to (450.00±141.42)J. However, both parameters increased again in the 140 times/min group [(4.75±1.04)times, (950.00±207.02)J], the differences among the groups were statistically significant (both P < 0.01). As compression frequency increased, P_ETCO₂, pre-defibrillation AOP and CPP significantly improved, peaking in the 120 times/min group [compared with the 60 times/min group, P_ETCO₂ (mmHg, 1 mmHg≈0.133 kPa): 18.69±1.98 vs. 8.67±1.30, AOP (mmHg): 95.13±7.06 vs. 71.00±6.41, CPP (mmHg): 14.88±6.92 vs. 8.57±3.42]. However, in the 140 times/min group, these values declined significantly again [P_ETCO₂, AOP, and CPP were (10.59±1.40), (72.38±11.49), and (10.36±4.57) mmHg, respectively], the differences among the groups were statistically significant (all P < 0.01). The number of animals achieving ROSC, successful resuscitation, and 24-hour survival increased with higher compression rates, reaching a peak in the 120 times/min group (compared with the 60 times/min group, ROSC: 7 vs. 2, successful resuscitation: 7 vs. 2, 24-hour survival: 7 vs.1), then decreased again in the 140 times/min group (the animals that ROSC, successfully recovered and survived for 24 hours were 3, 3, and 2, respectively). Transmission electron microscopy revealed that in the 60, 80, and 140 times/min groups, nuclear membranes in cerebral tissue were irregular and incomplete, nucleoli were indistinct, and mitochondria were swollen with reduced cristae and abnormal morphology. In contrast, the 100 times/min and 120 times/min groups exhibited significantly attenuated ultrastructural damage. CONCLUSIONS Among the tested chest compression rates of 60-140 times/min, a chest compressions frequency of 120 times/min is the most favorable hemodynamic profile and outcomes during CPR in a porcine CA model. However, due to the wide spacing between groups, further investigation is needed to determine the optimal compression rate range more precisely.
Animals ; Cardiopulmonary Resuscitation/methods* ; Swine ; Male ; Heart Arrest/therapy* ; Heart Massage/methods* ; Hemodynamics