Treatment Of Hypotension Research Articles

Đánh giá tác dụng dự phòng tụt huyết áp của Phenylephrine trong gây tê tủy sống ở phẫu thuật thay khớp háng ở bệnh nhân cao tuổi

Đặt vấn đề: Phương pháp gây tê tủy sống đơn thuần có những ưu điểm nổi bật , tuy nhiên tỉ lệ tụt huyết áp ở bệnh nhân cao tuổi trong phẫu thuật thay khớp háng khá cao, từ 40 - 46,67%. Sử dụng thuốc vận mạch dự phòng và điều trị tụt huyết áp trong mổ là một biện pháp vừa hạn chế được lượng dịch truyền cũng như có thể sử dụng đủ liều thuốc tê, đặc biệt là khi kết hợp bù dịch keo và sử dụng thuốc vận mạch dự phòng và điều trị tụt huyết áp. Nghiên cứu của chúng tôi thực hiện với mục tiêu đánh giá tác dụng dự phòng giữa hai nhóm có và không có sử dụng liều dự phòng phenylephrine trong gây tê tủy sống ở phẫu thuật thay khớp háng trên bệnh nhân cao tuổi. Đối tượng, phương pháp: 100 bệnh nhân cao tuổi (≥ 60 tuổi) được tiến hành phẫu thuật thay khớp háng theo kế hoạch, được chia ngẫu nhiên thành hai nhóm có sử dụng liều dự phòng 50 mcg phenylephrine và không sử dụng liều dự phòng phenylephrine. Phương pháp được thực hiện là nghiên cứu mô tả cắt ngang. Kết quả: Tỷ lệ tụt huyết áp ở hai nhóm dùng liều dự phòng và không dùng liều dự phòng bằng phenylephrine là 52% và 56% (p = 0.548). Số lần dùng thuốc điều trị tụt huyết áp và liều dùng ở 2 nhóm tương đương nhau. Kết luận: Liều dự phòng phenylephrine không làm giảm tỷ lệ tụt huyết áp sau gây tê tủy sống trong phẫu thuật thay khớp háng ở bệnh nhân cao tuổi. ABSTRACT ASSESSMENT THE PREVENTIONS EFFECTS OF PHENYLEPHRINE IN SPINAL ANESTHESIA FOR HIP REPLACEMENT SURGERY ON ELDERLY PATIENTS Vo Hoang Phu1,2, Nguyen Thanh Xuan1, Nguyen Viet Quang Hien1,3 Background: The method of spinal anesthesia alone has outstanding advantages, but the rate of hypotension in elderly patients in hip replacement surgery is quite high, from 40 to 46.67%. The use of vasopressors to prevent and treat hypotension during surgery is a measure that both limits the amount of fluid as well as can use a sufficient dose of local anesthetic, especially when combining colloidal replacement and drug use. vasopressor for prevention and treatment of hypotension. Our study was conducted with the aim of evaluating the prophylactic effect between two groups with and without the use of prophylactic doses of phenylephrine in spinal anesthesia in hip replacement surgery in elderly patients. Methods: 100 elderly patients (≥ 60 years of age) undergoing planned hip replacement surgery were randomly divided into two groups with and without a prophylactic dose of 50 mcg phenylephrine. The method used is a cross - sectional descriptive study. Results: The rate of hypotension in the two groups receiving prophylactic and non- prophylactic doses of phenylephrine was 52% and 56% (p = 0.548). The number of using antihypertensive drugs and the dose in the 2 groups were similar. Conclusions: Prophylactic doses of phenylephrine can’t reduction in the rate of hypotension after spinal anesthesia in hip replacement surgery in elderly patients.

Comparison of clinical outcomes between active and permissive blood pressure management in extremely preterm infants.

There remains uncertainty about the definition of normal blood pressure (BP), and when to initiate treatment for hypotension for extremely preterm infants. To determine the short-term outcomes of extremely preterm infants managed by active compared with permissive BP support regimens during the first 72 hours of life. This is a retrospective medical records review of 23 +0-28 +6 weeks' gestational age (GA) infants admitted to neonatal units (NNU) with active BP support (aimed to maintain mean arterial BP (MABP) >30 mmHg irrespective of the GA) and permissive BP support (used medication only when babies developed signs of hypotension) regimens. Babies admitted after 12 hours of age, or whose BP data were not available were excluded. There were 764 infants admitted to the participating hospitals; 671 (88%) were included in the analysis (263 active BP support and 408 permissive BP support). The mean gestational age, birth weight, admission temperature, clinical risk index for babies (CRIB) score and first haemoglobin of infants were comparable between the groups. Active BP support group infants had consistently higher MABP and systolic BP throughout the first 72 hours of life (p<0.01). In the active group compared to the permissive group 56 (21.3%) vs 104 (25.5%) babies died, and 21 (8%) vs 51 (12.5%) developed >grade 2 intra ventricular haemorrhage (IVH). Death before discharge (adjusted OR 1.38 (0.88 - 2.16)) or IVH (1.38 (0.96 - 1.98)) was similar between the two groups. Necrotising enterocolitis (NEC) ≥stage 2 was significantly higher in permissive BP support group infants (1.65 (1.07 - 2.50)). There was no difference in mortality or IVH between the two BP management approaches. Active BP support may reduce NEC. This should be investigated prospectively in large multicentre randomised studies.

TREATMENT OF ARTERIAL HYPOTENSION

Treatment of arterial hypotension is a complex problem that requires correction of the hemodynamic parameters of the patient and, if possible, an impact on the cause of a decrease in blood pressure. It is necessary to pay attention to the correction of factors aggravating the course of hypotension. It is also important to use non-drug methods of correction of low blood pressure, such as wearing compression underwear, increasing fluid and salt intake, the use of physical maneuvers and exercises. Pharmacological therapy of hypotension includes the use of a number of drugs with different mechanisms of action, such as midodrine, fludcortisone, droxidopa, norepinephrine membrane transporter inhibitors. Special attention is paid to the treatment of orthostatic hypotension, postprandial hypotension.

Intra-operative hypotension in anaesthetised horses

The prompt and effective treatment of hypotension is important in order to avoid its negative consequences, but the management of hypotension may not always be straight forward. Treatment options may include reducing delivered volatile agent concentration, optimising circulating volume and administering positive inotropes or vasopressor agents. In order to approach treatment in the most effective way, it is important to address the underlying cause of or the most significant factor which may be contributing to suboptimal arterial blood pressure. This article summarises the causes of hypotension and various approaches to management and treatment.

Association of the exclusive use of intraoperative phenylephrine for treatment of hypotension with the risk of acute kidney injury after noncardiac surgery

Study objectiveThe hypothesis that the exclusive use of the commonly used vasopressor phenylephrine during the intraoperative period in noncardiac surgery is associated with postoperative acute kidney injury (AKI) was tested. DesignA retrospective cohort analysis of 16,306 adults undergoing major noncardiac surgery who either did or did not receive phenylephrine was conducted. The primary outcome was the association of the use of phenylephrine with the risk of postoperative AKI defined by the Kidney Disease Improving Global Outcomes (KDIGO) criteria. Logistic regression models with all independently associated potential confounders, and an exploratory model considering only patients with no untreated minutes of hypotension (post-phenylephrine in the exposed cohort, or entire case in the unexposed cohort) were used in the analysis. SettingThe study was conducted in a tertiary care university hospital where a total of 8,221 patients were exposed to phenylephrine, and 8,085 were not. ResultsIn unadjusted analysis, phenylephrine exposure was associated with an increased risk of AKI (OR 1.615, 95% CI [1.522–1.725], p < 0.001). In an adjusted model including several variables associated with AKI, phenylephrine remained associated with AKI (OR 1.325 [1.153–1.524]), as did post-phenylephrine exposure lengths of hypotension. Exclusion of patients with >1 min of post-phenylephrine exposure hypotension, also demonstrated that phenylephrine use was associated with AKI (OR 1.478, [1.245–1.753]). ConclusionsThe exclusive use of intraoperative phenylephrine is associated with an increased risk of postoperative renal injury. Anesthesiologists must consider a balanced approach to correct hypotension under anesthesia, including judicious choices for fluids, inotropic support when indicated, and an appropriate adjustment of the plane of anesthesia.

Hemodynamic instability predicts in-hospital and 1-year mortality after transcarotid artery revascularization and transfemoral carotid stenting

ObjectiveBlood pressure fluctuations are a common hemodynamic alteration following carotid artery stenting either with transfemoral (TFCAS) or transcarotid (TCAR) approach and are thought to be related to alteration in baroreceptor function due to angioplasty and stent expansion. These fluctuations are particularly worrisome in the high-risk patient population referred for CAS. This study aims to evaluate the outcomes of patients who required the administration of intravenous blood pressure medication (IVBPmed) for hypotension or hypertension after CAS. MethodsAll patients undergoing carotid revascularization in the Vascular Quality Initiative (VQI) database between 2016 and 2021 were included. We compared outcomes of patients who required postoperative IVBPmed to treat hyper- or hypotension with normotensive patients. In-hospital outcomes were compared using multivariable logistic regression. One-year outcomes were assessed using Kaplan-Meier survival and multivariable Cox proportional hazard regression analyses. ResultsWe identified 38,510 patients undergoing CAS (57.7% TCAR and 42.3% TFCAS), of which, 30% received IVBPmed for treatment of either postoperative hypertension (12.6%) or hypotension (16.4%). In multivariable analysis, postoperative hypotension was associated with a higher risk of stroke, death, or myocardial infarction (MI) (odds ratio [OR], 3.1; 95% confidence interval [CI], 2.6-3.6; P < .001), stroke or death (OR, 2.9; 95% CI, 2.4-3.5; P < .001), stroke (OR, 2.6; 95% CI, 2.1-3.2; P < .001), death (OR, 3.5; 95% CI, 2.6-4.8; P < .001), MI (OR, 4.7; 95% CI, 3.3-6.7; P < .001), and bleeding (OR, 1.96; 95% CI, 1.4-2.7; P < .001) compared with normotensive patients. Postoperative hypertension was associated with a higher risk of stroke, death, or MI (OR, 3.6; 95% CI, 3-4.4; P < .001), stroke or death (OR, 3.3; 95% CI, 2.7-4.1; P < .001), stroke (OR, 3.7; 95% CI, 3-4.7; P < .001), death (OR, 2.7; 95% CI, 1.9-3.9; P < .001), MI (OR, 5.7; 95% CI, 3.9-8.3; P < .001), and bleeding (OR, 1.9; 95% CI, 1.4-2.7; P < .001) compared with normotensive patients. ConclusionsPostoperative hypertension or hypotension requiring IVBPmed after CAS is associated with an increased risk of in-hospital stroke, death, MI, and bleeding. Postoperative hypertension is associated with worse survival at 1 year. This study indicates that the need for IVBPmed after CAS is not benign; therefore, these patients necessitate aggressive perioperative medical management and safe techniques to avoid hypo and hypertension. Close follow-up and continue medical management are needed to maximize these patients’ survival.

Continuous Epidural Saline Infusion for the Treatment of Spontaneous Intracranial Hypotension.

Spontaneous intracranial hypotension (SIH) is an increasingly recognized cause of orthostatic headache, but treatment strategies remain controversial. The epidural blood patch is a well-known and widely used treatment in patients with conservative treatment-resistant SIH, but symptoms may not improve even after multiple epidural blood patches, and resistant patients suffer from a lack of appropriate treatment options. Therefore, this study assessed the safety and efficacy of continuous epidural saline infusion (CESI) for SIH treatment. CESI was performed in 11 consecutive patients affected by conservative treatment-resistant SIH. Patient characteristics were obtained by reviewing medical records retrospectively. Headache intensity was assessed using the numerical rating scale (NRS), and changes in NRS before and after treatment were recorded. The average treatment period for CESI was 21.3±9.6days, and the average follow-up period was 35.0±30.2months. CESI was without major complications or mortality, and no infections occurred, even without prophylactic antibiotics. The median NRS score before treatment was 10 points, improving to 5 points 1day after infusion (P < 0.05), 2 points 1week after infusion (P < 0.05), and 0 points at 3months after infusion and the final follow-up. No patients have since experienced recurrence of orthostatic headaches. CESI appears to be a safe and well-tolerated procedure for SIH. Further experience may demonstrate this technique to be a viable treatment option for SIH.

Incidence of bradycardia during noradrenaline or phenylephrine bolus treatment of postspinal hypotension in cesarean delivery: A randomized double-blinded controlled trial.

The treatment of choice for spinal anesthesia-induced hypotension during cesarean section is phenylephrine. As this vasopressor can cause reflex bradycardia, noradrenaline is a suggested alternative. This randomized double-blinded controlled trial included 76 parturients undergoing elective cesarean delivery under spinal anesthesia. Women received noradrenaline in bolus doses of 5mcg or phenylephrine in bolus doses of 100 mcg. These drugs were used intermittently and therapeutically to maintain systolic blood pressure ≥ 90% of its baseline value. The primary study outcome was bradycardia incidence (<60 bpm) with intermittent bolus administration of these drugs. Secondary outcomes included extreme bradycardia (<40 bpm), number of bradycardia episodes, hypertension (systolic blood pressure > 120% of baseline value), and hypotension (systolic blood pressure < 90% of baseline value and requiring vasopressor use). Neonatal outcomes per the Apgar scale and umbilical cord blood gas analysis were also compared. The incidence of bradycardia in both groups (51.4% and 70.3%, respectively; p=0.16) were not significantly different. No neonates had umbilical vein or artery pH values below 7.20. The noradrenaline group required more boluses than phenylephrine group (8 vs. 5; p=0.01). There was no significant intergroup difference in any of the other secondary outcomes. When administered in intermittent bolus doses for the treatment of postspinal hypotension in elective cesarean delivery, noradrenaline, and phenylephrine have a similar incidence of bradycardia. When treating hypotension related to spinal anesthesia in obstetric cases, strong vasopressors are commonly administered, thought these can also have side effects. This trial assessed bradycardia after bolus administration of noradrenaline or phenylephrine, and found no difference in risk for clinically meaningful bradycardia.

Aggregatibacter actinomycetemcomitans Endocarditis in a Patient with Chronic Periodontitis: A Case Report

The HACEK organisms consist of the non-influenzae Haemophilus sp., Aggregatibacter sp., Cardiobacterium sp., Eikenella corrodens and Kingella sp. are responsible for a sizable percentage of infective endocarditis cases worldwide with the mortality rate of 18%. Amongst them, Aggregatibacter actinomycetemcomitans is the most common pathogen strongly associated with infective endocarditis. A. actinomycetemcomitans forms part of the oral microbiota and is also the etiological agent of periodontitis. Here, we present a case of a 37-year-old man with underlying obstructive uropathy, that sought treatment for postural hypotension and symptomatic anaemia with fever. Later, he had developed decompensated congestive cardiac failure with aortic regurgitation. A cardiac echocardiogram revealed the presence of vegetation on the aortic valve. Blood culture grew A. actinomycetemcomitans, and he was treated with furosemide and ceftriaxone. A further dental examination showed the patient is having chronic periodontitis, which could be the possible source of A. actinomycetemcomitans causing infective endocarditis. The patient was then transferred to the National Heart Centre for the first time for further management after completion of 4 weeks of intravenous antibiotics. As the pathogen is fastidious, rapid and newer technology like MALDI-TOF mass spectrometry provides rapid and accurate identification for appropriate patient clinical management.

The effect of two dose phenylephrin for preventing hypotension during spinal anesthesia for cesarean delivery

Background: Spinal anesthesia-induced hypotension is one of the most complications which can cause many severe maternal and fetal complications. Therefore, the prevention and treatment of spinal anesthesia-induced hypotension in pregnant women undergoing cesarean delivery play an important role. The use of vasopressors is the most effective method of hypotensive prophylaxis and phenylephrine is currently the first-line vasopressor of choice to prevent this complication. The aim of this study is to evaluate the effectiveness and safety of two-dose phenylephrine for prevention of spinal anesthesia-induced hypotension during cesarean delivery. Materials and methods: In a randommized controlled clinical trial, 150 pregnants undregoing cesarean delivery with spinal anesthesia were randomly divided into three groups: Group I: as a control group without phenylephrine prophylaxis (n = 50), Group II: 50µg intravenously bolus phenylephrine (n = 50), and Group III: 75µg intravenously bolus phenylephrine (n = 50) immediately after induction of spinal anesthesia. Hypotension, defined decreasing systolic blood pressure &gt; 20% of baseline. The incidence of hypotension, levels of hypotension, maternal side effects and neonatal APGAR scores at 1 and 5 minutes. Results: The incidence of hypotension was 44%, the incidence of re-hypotension was 16%. Group III: the incidence of hypotension was 28%, the incidence of re-hypotension was 2%. The neonatal APGAR scores of the two groups at both 1 minute and 5 minutes was the same (p &gt; 0.05), all cases had APGAR &gt; 7. Conclusion: Phenylephrine intravenous bolus at doses of 50 µg and 75 µg are both effective for the prevention spinal anesthesia-induced hypotension for cesarean section. However, the 75 µg phenylephrine dose was more effective than the 50 µg dose because of lower rates of hypotension and recurrent hypotension (28% and 2% vs 44% and 16%, p &lt; 0.05). In addition, both groups of prophylactic phenylephrine didn’t cause detrimental adverses for parturients and their babies. Key words: Hypotensive prophylaxis, cesarean section, phenylephrin.

Evaluating an advanced double intravenous vasopressor automated system to treat hypotension during spinal anesthesia for cesarean delivery: a randomized controlled trial

BackgroundThe optimal treatment of hypotension during spinal anaesthesia is uncertain. A novel double intravenous vasopressor automated (DIVA) system reduces hypotension compared to standard care, and was subsequently modified to an advanced-DIVA (ADIVA) system. The primary objective was to compare ADIVA versus DIVA on incidence of hypotension (systolic BP (SBP) < 80% baseline).MethodsWe conducted a randomized-controlled trial in women undergoing elective cesarean delivery under spinal anesthesia. SBP and heart rate were measured continuously using a Nexfin monitor. ADIVA delivered 25 μg phenylephrine (heart rate > 60 beats.min−1) or 2 mg ephedrine (heart rate < 60 beats.min−1) at SBP 90 to 110% of baseline, 50 μg phenylephrine or 4 mg ephedrine at SBP 80 to 90%, and 75 μg phenylephrine or 6 mg ephedrine at SBP < 80%. ADIVA calculated the trend of SBP; vasopressors were administered rapidly if SBP trended downward, or 30 s if SBP trended upward. In contrast, DIVA delivered 25 μg phenylephrine or 2 mg ephedrine at SBP 90 to 100% of baseline, and 50 μg phenylephrine or 4 mg ephedrine at SBP < 90%. Boluses were followed by a 10-s lockout. Other outcomes included hypertension (SBP > 120% baseline), vasopressor consumption, clinical outcomes, and performance measures from spinal anesthesia to fetal delivery.ResultsWe analyzed 94 parturients (ADIVA: n = 46, DIVA: n = 48), with no difference in the incidence of hypotension between ADIVA (78.3%) and DIVA (83.3%, p = 0.677). ADIVA had significantly higher proportion of hypotensive SBP readings, lower phenylephrine consumption and higher umbilical arterial pH. There was no difference in hypertension, bradycardia, ephedrine consumption, intravenous fluid volume, nausea/vomiting, Apgar scores, and umbilical venous pH or lactate. ADIVA maintained SBP higher above baseline with greater fluctuation than DIVA. ConclusionADIVA was associated with a greater proportion of hypotensive SBP readings, reduced phenylephrine consumption, and increased umbilical arterial pH than DIVA. Further research is needed to determine the optimal method of vasopressor delivery in parturients undergoing cesarean delivery.Trial registrationThis study was registered on Clinicaltrials.gov registry (NCT03620942) on 08/08/2018.

Comparison of clinical outcomes between active and permissive blood pressure management in extremely preterm infants

Background There remains uncertainty about the definition of normal blood pressure (BP), and when to initiate treatment for hypotension for extremely preterm infants. To determine the short-term outcomes of extremely preterm infants managed by active compared with permissive BP support regimens during the first 72 hours of life. Method This is a retrospective medical records review of 23+0–28+6 weeks’ gestational age (GA) infants admitted to neonatal units (NNU) with active BP support (aimed to maintain mean arterial BP (MABP) &gt;30 mmHg irrespective of the GA) and permissive BP support (used medication only when babies developed signs of hypotension) regimens. Babies admitted after 12 hours of age, or whose BP data were not available were excluded. Results There were 764 infants admitted to the participating hospitals; 671 (88%) were included in the analysis (263 active BP support and 408 permissive BP support). The mean gestational age, birth weight, admission temperature, clinical risk index for babies (CRIB) score and first haemoglobin of infants were comparable between the groups. Active BP support group infants had consistently higher MABP and systolic BP throughout the first 72 hours of life (p&lt;0.01). In the active group compared to the permissive group 56 (21.3%) vs 104 (25.5%) babies died, and 21 (8%) vs 51 (12.5%) developed &gt;grade 2 intra ventricular haemorrhage (IVH). Death before discharge (adjusted OR 1.38 (0.88 – 2.16)) or IVH (1.38 (0.96 – 1.98)) was similar between the two groups. Necrotising enterocolitis (NEC) ≥stage 2 was significantly higher in permissive BP support group infants (1.65 (1.07 – 2.50)). Conclusions There was no difference in mortality or IVH between the two BP management approaches. Active BP support may reduce NEC. This should be investigated prospectively in large multicentre randomised studies.

Ephedrine Infusion with Rescue Ephedrine Boluses versus Rescue Boluses alone for Preventing Hypotension during Spinal Anesthesia for Cesarean Delivery.

Background: Maternal hypotension is an unwanted consequence of the physiologic onset of spinal blockade, and causes both maternal and fetal effects. Maternal symptoms include nausea, vomiting, and a sense of ‘‘impending doom’’ from inadequate cerebral perfusion. Inadequate treatment of hypotension can ultimately end with the loss of consciousness and cardiovascular collapse.&#x0D; Materials and methods: We included 80 full term parturient (ASA I or II) with uncomplicated pregnancies. The patients were prospectively randomized into two groups. 80 patients received 1000 mL NaCl 0,9 % solution before the initiation of spinal anesthesia. Maternal systolic blood pressure was measured every 1 minutes (for first 10 minutes) and then every 3 minutes. One group received ephedrine infusion (1 mg/min) with rescue ephedrine boluses (10 mg), (usually defined as a maternal blood pressure ˂ 30% above baseline), (40 patients) and the other received rescue boluses alone (10 mg) , (usually defined as a maternal blood pressure ˂ 30% above baseline), (40 patients).&#x0D; Results: Gr 1 (Ephedrine infusion with rescue ephedrine boluses). The incidence of hypotension was at 8 patients (8/40 [20%]),(when an absolute value of less than 90 mmHg).&#x0D; Gr 2 (rescue boluses ephedrine alone). The incidence of hypotension was at 32 patients (32/40 [80%]), (when an absolute value of less than 90 mmHg).&#x0D; Group 2 had a higher incidence of hypotension compared with group 1 (32/40 [80%]) vs (8/40 [20%]).&#x0D; Neonatal outcomes were not different between the 2 groups.&#x0D; Conclusion: Prophylactic variable rate ephedrine infusion and rescue ephedrine bolus dosing is more effective than relying on rescue ephedrine bolus dosing with respect to limiting clinician workload and maternal symptoms during spinal anesthesia for cesarean delivery.Maternal hypotension

Evaluation of urine specific gravity as a predictor of hypotension during anaesthesia in healthy dogs premedicated with dexmedetomidine

ObjectiveTo investigate the relationship between urine specific gravity (USG) and the risk of arterial hypotension during general anaesthesia (GA) in healthy dogs premedicated with dexmedetomidine and methadone. Study designProspective clinical cohort study. AnimalsA total of 75 healthy client-owned dogs undergoing GA for elective tibial plateau levelling osteotomy. MethodsAfter placing an intravenous catheter, dogs were premedicated with dexmedetomidine (5 μg kg–1) and methadone (0.3 mg kg–1) intravenously. After induction of GA with alfaxalone to effect, the bladder was expressed and USG measured. An arterial catheter was placed, and residual blood was used to measure packed cell volume (PCV) and total protein (TP). GA was maintained with isoflurane vaporised in oxygen and a femoral and sciatic nerve block were performed. Arterial blood pressure < 60 mmHg was defined as hypotension and recorded by the anaesthetist. Treatment for hypotension was performed in a stepwise manner following a flow chart. Frequency of hypotension, treatment and response to treatment were recorded. Logistic regression modelling was used to assess the association between USG, TP and PCV and incidence of perioperative hypotension; p < 0.05. ResultsData from 14 dogs were excluded. Of the 61 dogs, 16 (26%) were hypotensive during GA, 15 dogs needed treatment of which 12 were responsive to a decrease in inhalant vaporiser setting. The logistic regression model was not statistically significant (p = 0.8). There was no significant association between USG (p = 0.6), TP (p = 0.4), PCV (p = 0.8) and arterial hypotension during GA. Conclusions and clinical relevanceIn healthy dogs premedicated with dexmedetomidine and methadone and maintained under GA with isoflurane and a femoral and sciatic nerve block, there was no relationship between the specific gravity of urine collected after premedication and intraoperative arterial hypotension.

Effective dose of ephedrine for treatment of hypotension after induction of general anaesthesia in neonates and infants less than 6 months of age: a multicentre randomised, controlled, open label, dose escalation trial

BackgroundThe recommended dose of ephedrine in adults (0.1 mg kg−1) frequently fails to treat hypotension after induction of general anaesthesia in neonates and infants less than 6 months of age. The aim of this study was to determine the optimal dose of ephedrine in this population for the treatment of hypotension after induction of general anaesthesia with sevoflurane. MethodsWe conducted a multicentre, prospective, randomised, open-label, controlled, dose-escalation trial. Subjects were randomised if presenting a >20% change from baseline in MAP. Six cohorts of 20 subjects each were enrolled. Ten subjects in the first cohort received 0.1 mg kg−1 i. v. (reference dose). For each subsequent cohort, 10 subjects were assigned to the next higher dose (consecutively 0.6, 0.8, 1, 1.2, and 1.4 mg kg−1 i. v.), and the other subjects were assigned to one or more doses already investigated in previous cohorts. The primary outcome was the return of MAP to >80% of baseline at least once within 10 min after ephedrine administration. ResultsA total of 119 infants (25% females), with a mean age (standard deviation) of 2.7 (1.3) months, received their allocated dose of ephedrine. The optimal dose of ephedrine was 1.2 mg kg−1, with a percentage of success of 65.5% (95% confidence interval, 35.6–86.4). The doses of ephedrine investigated did not induce adverse events. ConclusionsDoses of ephedrine much higher (∼10-fold) than those used in adults are necessary in neonates and infants for the treatment of hypotension after induction of general anaesthesia with sevoflurane. Clinical trial registrationNCT02384876.

Continuous Positive Airway Pressure for the Treatment of Supine Hypertension and Orthostatic Hypotension in Autonomic Failure.

Supine hypertension affects most patients with orthostatic hypotension (OH) due to autonomic failure, but it is often untreated for fear of worsening OH. We hypothesized that increasing intrathoracic pressure with continuous positive airway pressure (CPAP) had a Valsalva-like blood-pressure-lowering effect that could be used to treat nocturnal supine hypertension in these patients, while reducing nocturnal pressure diuresis and improving daytime OH. In Protocol 1, we determined the acute hemodynamic effects of increasing levels of CPAP (0, 4, 8, 12, and 16 cm H2O, 3 minutes each) in 26 patients with autonomic failure and supine hypertension studied while awake and supine. In Protocol 2 (n=11), we compared the effects of overnight therapy with CPAP (8-12 cm H2O for 8 hours) versus placebo on nocturnal supine hypertension, nocturnal diuresis and daytime OH in a 2-night crossover study. In Protocol 1, acute CPAP (4-16 cm H2O) decreased systolic blood pressure in a dose-dependent manner (maximal drop 22±4 mmHg with CPAP 16) due to reductions in stroke volume (-16+3%) and cardiac output (-14±3%). Systemic vascular resistance and heart rate remained unchanged. In Protocol 2, overnight CPAP lowered nighttime systolic blood pressure (maximal change -23±5 versus placebo -1±7 mmHg; P=0.023) and was associated with lower nighttime diuresis (609±84 versus placebo 1004±160 mL; P=0.004) and improved morning orthostatic tolerance (AUC upright SBP 642±121 versus placebo 410±109 mmHg*min; P=0.014). CPAP is a novel nonpharmacologic approach to treat the supine hypertension of autonomic failure while improving nocturia and daytime OH. URL: https://www. gov; Unique identifier: NCT03312556.

Comparison of Bolus Ephedrine vs Mephentermine in the Management of Hypotension during Spinal Anaesthesia for Caesarean Section: A Randomised Clinical Trial

Introduction: Ephedrine and mephentermine are synthetic sympathomimetic drugs used as vasopressors. Ephedrine has direct and indirect effects on α, b1, and b2 receptors, and it also releases endogenous norepinephrine from synaptic storage sites. This leads to an elevation in Systolic Blood Pressure (SBP) and Diastolic Blood Pressure (DBP). On the other hand, mephentermine indirectly stimulates beta-adrenergic receptors and to some extent alpha-adrenergic receptors as well. Its primary effect is cardiac stimulation, which increases peripheral vascular resistance and contributes to an increase in blood pressure. Aim: The aim of this study is to examine the efficacy of ephedrine and mephentermine in the treatment of hypotension during Lower Segment Caesarean Section (LSCS). Materials and Methods: This double-blinded randomised clinical trial was conducted in the Department of Anaesthesiology among 90 pregnant females scheduled for caesarean delivery at Hind Institute of Medical Sciences, Sitapur, India from January 2021 to December 2022. Patients who developed hypotension (SBP &lt;90 mmHg or &lt;20% of the baseline) after receiving spinal anaesthesia were included in the study and divided into two groups. Group A received an intravenous bolus of 6 mg of ephedrine, and group B received an intravenous bolus of 6 mg of mephentermine. The variables studied included age, height, weight, Mean Arterial Pressure (MAP), Heart Rate (HR), SBP, DBP, bolus doses, and any side effects that occurred. HR, SBP, and DBP were recorded at baseline and then monitored every two minutes for a total of 10 minutes, and then every five minutes until the end of surgery. Statistical analysis was performed using Statistical Package for Social Sciences (SPSS) software version 21.0 for Windows, and the results were represented as numbers (%) and mean±Standard Deviation (SD). Results: The mean age of patients in group A and group B was 24.35 years and 24.72 years, respectively. All vital parameters were comparable. The need for bolus doses after hypotension was significantly higher in group B (1.68±0.81) than in group A (mean 1.28). The statistically significant complications identified were tachycardia, nausea, and vomiting, which were more prevalent in group B with 13 and 16 patients, respectively. Conclusion: In this study, the authors found that ephedrine was more effective than mephentermine in terms of the requirement for bolus doses and the occurrence of intraoperative side effects. The requirement for bolus doses and occurrence of significant complications were higher in the group that received mephentermine. Therefore, ephedrine bolus immediately following spinal anaesthesia would be a safe and effective technique for preventing hypotension in females scheduled for Lower Segment Caesarean Section (LSCS).

Application Value of Limb Ischemic Preconditioning in Preventing Intradialytic Hypotension during Maintenance Hemodialysis

Introduction: The aim of this study was to investigate the efficacy and safety of limb ischemia preconditioning (LIPC) in the treatment of intradialytic hypotension (IDH) in patients with maintenance hemodialysis (MHD). Methods: This was a single-center, prospective, and randomized controlled case study. A total of 38 patients with MHD who met the inclusion criteria from September 2021 to August 2022 were selected from the Blood Purification Center of our hospital. They were randomly divided into the LIPC group (n = 19) and the control group (n = 19). For patients in the LIPC group, the femoral artery blood flow was blocked with an LIPC instrument for 5 min (pressurized to 200 mm Hg) before each dialysis, and they were reperfused for 5 min. The cycle was repeated five times, with a total of 50 min for 12 weeks. The control group was pressurized to 20 mm Hg with an LIPC instrument, and the rest was the same as the LIPC group. The blood pressure of 0 h, 1 h, 2 h, 3 h, 4 h, and body weight before and after hemodialysis were measured in the two groups during hemodialysis, the incidence of IDH and the changes of serum troponin I (TNI) and creatine kinase isoenzyme MB (CK-MB) levels before and after the intervention were observed, and the ultrafiltration volume and ultrafiltration rate were recorded. Results: At the 8th and 12th week after intervention, the MAP in the LIPC group was higher than that in the control group (103.28 ± 12.19 mm Hg vs. 93.18 ± 11.11 mm Hg, p = 0.04; 101.81 ± 11.36 mm Hg vs. 91.81 ± 11.92 mm Hg, p = 0.047). The incidence of IDH in the LIPC group was lower than that in the control group (36.5% vs. 43.1%, p = 0.01). The incidence of clinical treatment in IDH patients in the LIPC group was lower than that in the control group (6.3% vs. 12.4%, p = 0.00). The incidence of early termination of hemodialysis in the LIPC group was lower than that in the control group (1.6% vs. 3.8%, p = 0.01). The levels of TNI and CK-MB in the LIPC group after the intervention were lower than those in the control group (322.30 ± 13.72 ng/dL vs. 438.50 ± 24.72 ng/dL, p = 0.00; 159.78 ± 8.48 U/dL vs. 207.00 ± 8.70 U/dL, p = 0.00). The changes of MAP before and after the intervention were negatively correlated with the changes of TNI and CK-MB before and after the intervention (r = −0.473, p = 0.04; r = −0.469, p = 0.04). There were no differences in dry body mass and ultrafiltration rate between the two groups before and after the LIPC intervention (p > 0.05). Multiple linear regression analysis shows that TNI is the main influencing factor of ΔMAP. No LIPC-related adverse events were found during the study period. Conclusion: LIPC can effectively reduce the incidence of IDH in patients with MHD and may be associated with the alleviation of myocardial damage.

Effects of Atomoxetine for the Treatment of Neurogenic Orthostatic Hypotension in Patients With Alpha-synucleinopathies: A Systematic Review of Randomized Controlled Trials and a Focus-Group Discussion.

Neurogenic orthostatic hypotension (nOH) is one of the most important nonmotor symptoms in patients with α-synucleinopathies. Atomoxetine is a selective norepinephrine transporter blocker that is a treatment option for nOH. This systematic review and expert focus-group study was designed to obtain evidence from published data and clinical experiences of Korean movement-disorder specialists about the efficacy and safety of atomoxetine for the pharmacological treatment of nOH in patients with α-synucleinopathies. The study comprised a systematic review and a focus-group discussion with clinicians. For the systematic review, multiple comprehensive databases including MEDLINE, Embase, Cochrane Library, CINAHL, PsycInfo, and KoreaMed were searched to retrieve articles that assessed the outcomes of atomoxetine therapy. A focus-group discussion was additionally performed to solicit opinions from experts with experience in managing nOH. The literature review process yielded only four randomized controlled trials on atomoxetine matching the inclusion criteria. Atomoxetine effectively increased systolic blood pressure and improved OH-related symptoms as monotherapy or in combination with other drugs. Its effects were pronounced in cases with central autonomic failure, including multiple-system atrophy (MSA). Atomoxetine might be a safe monotherapy regarding the risk of supine hypertension. Atomoxetine is an effective and safe option for short-term nOH management, which could be more evident in patients with central autonomic dysfunction such as MSA. However, there is a paucity of evidence in the literature, and data from the focus-group discussion were inadequate, and so further investigation is warranted.

Correlation between prehospital and in-hospital hypotension and outcomes after traumatic brain injury

Background and objectiveHypotension has a powerful effect on patient outcome after traumatic brain injury (TBI). The relative impact of hypotension occurring in the field versus during early hospital resuscitation is unknown. We evaluated the association between hypotension and mortality and non-mortality outcomes in four cohorts defined by where the hypotension occurred [neither prehospital nor hospital, prehospital only, hospital only, both prehospital and hospital]. MethodsSubjects ≥10 years with major TBI were included. Standard statistics were used for unadjusted analyses. We used logistic regression, controlling for significant confounders, to determine the adjusted odds (aOR) for outcomes in each of the three cohorts. ResultsIncluded were 12,582 subjects (69.8% male; median age 44 (IQR 26–61). Mortality by hypotension status: No hypotension: 9.2% (95%CI: 8.7–9.8%); EMS hypotension only: 27.8% (24.6–31.2%); hospital hypotension only: 45.6% (39.1–52.1%); combined EMS/hospital hypotension 57.6% (50.0–65.0%); (p < 0.0001). The aOR for death reflected the same progression: 1.0 (reference-no hypotension), 1.8 (1.39–2.33), 2.61 (1.73–3.94), and 4.36 (2.78–6.84), respectively. The proportion of subjects having hospital hypotension was 19.0% (16.5–21.7%) in those with EMS hypotension compared to 2.0% (1.8–2.3%) for those without (p < 0.0001). Additionally, the proportion of patients with TC hypotension was increased even with EMS “near hypotension” up to an SBP of 120 mmHg [(aOR 3.78 (2.97, 4.82)]. ConclusionWhile patients with hypotension in the field or on arrival at the trauma center had markedly increased risk of death compared to those with no hypotension, those with prehospital hypotension that was not resolved before hospital arrival had, by far, the highest odds of death. Furthermore, TBI patients who had prehospital hypotension were five times more likely to arrive hypotensive at the trauma center than those who did not. Finally, even “near-hypotension” in the field was strongly and independently associated the risk of a hypotensive hospital arrival (<90 mmHg). These findings are supportive of the prehospital guidelines that recommend aggressive prevention and treatment of hypotension in major TBI.