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Journal of Clinical and Translational... Jun 2023Acute ischemic colitis (IC) has been linked with the use of oral decongestants. However, clinical evidence on this association remains limited. We aim to evaluate the... (Review)
Review
BACKGROUND AND AIM
Acute ischemic colitis (IC) has been linked with the use of oral decongestants. However, clinical evidence on this association remains limited. We aim to evaluate the occurrence and clinical outcomes of acute IC following over-the-counter (OTC) use of pseudoephedrine and phenylephrine.
METHODS
We conducted a systematic review of the MEDLINE, Google Scholar, Scopus, and Embase databases between inception and July 20, 2022. Specific search terms were used. The inclusion criteria consisted of English-language articles describing acute IC secondary to pseudoephedrine or phenylephrine.
RESULTS
A total of 18 case reports (level of clinical evidence: IV) fulfilled our inclusion criteria. The mean age of patients was 51.6 ± 15.3 years, with 14 (77.8%) cases reported in women. The clinical presentation was mainly related to abdominal pain 16 (88.9%), hematochezia 15 (83.3%), and/or abdominal tenderness 10 (55.6%). The medical background showed that 5 (27.8%) patients were previously healthy. In the 13 (72.2%) patients with comorbidities, hypertension 6 (46.2%), a history of tobacco use 5 (38.5%), and psychiatric illnesses 4 (30.8%) were commonly reported. Leukocytosis was encountered in 13 (72.2%) patients. Diagnostic investigations included a combination of computed tomography scan and colonoscopy in 10 (55.6%), colonoscopy alone in 6 (33.3%), and flexible sigmoidoscopy in 1 (5.6%) patient. Colonoscopic biopsy was the mainstay of diagnosis in 15 (83.3%) patients. Treatment was based on supportive care in 18 (100%), concurrent antibiotic use in 2 (11.1%), and surgical intervention in 1 (5.6%) patient. Recurrent episodes of IC occurred in 4 (22.2%) patients.
CONCLUSIONS
Acute IC secondary to oral decongestants remains a rare but important clinical phenomenon. Clinical suspicion and imaging findings are important for the early diagnosis.
RELEVANCE TO PATIENTS
In unexplained cases of IC, clinicians should specifically inquire about oral decongestants since they are OTC and patients commonly fail to reveal their usage. These drugs should be avoided for transient cold symptoms, especially in women.
PubMed: 37275581
DOI: No ID Found -
Journal of Ocular Pharmacology and... Dec 2017To compare the effectiveness of intracameral phenylephrine and topical mydriatics in achieving mydriasis and protecting against complications during phacoemulsification. (Meta-Analysis)
Meta-Analysis Review
PURPOSE
To compare the effectiveness of intracameral phenylephrine and topical mydriatics in achieving mydriasis and protecting against complications during phacoemulsification.
METHODS
A systematic search of the literature comparing the mydriatic effect and surgical safety profile of intracameral phenylephrine and topical mydriatics in phacoemulsification was conducted in the Medline, Embase, Lilacs, Web of Science, Cochrane, ClinicalTrials.gov , and Teseo databases. The search targeted clinical trials, cohort studies, and case-control studies published between April 20, 2003 and August 14, 2016. Mydriatic effect was assessed by difference in means in pupil of all the patients in the studies [mean difference (MD)] and intraoperative complications were assessed by using inverse-variance weighted odds ratios (ORs), with adjustment for dose. A meta-regression analysis was also conducted, with adjustment for dose, use of epinephrine, tamsulosin use, and type of surgery and type of intraocular lens.
RESULTS
We found 7 articles about mydriatic effect and another 7 about complications. Intracameral phenylephrine achieved a similar mydriatic effect to topical mydriatics, with a difference of less than 10% (MD -0.74 mm, 95% CI: -1.67 to 0.18, I = 95.8%, P < 0.0001). The pooled OR for complications was OR 0.50, 95% CI: 0.19-1.31, I = 0.0%, P = 0.670, and posterior capsular rupture was the most common complication in the different studies analyzed.
CONCLUSION
Intracameral phenylephrine achieves a similar mydriatic effect to topical mydriatics (difference <15%) and is associated with a not-significant effect on reducing the odds of intraoperative complications.
Topics: Animals; Anterior Chamber; Humans; Intraoperative Complications; Mydriatics; Phacoemulsification; Phenylephrine; Pupil
PubMed: 29099656
DOI: 10.1089/jop.2017.0084 -
The European Respiratory Journal Mar 2022Obstructive sleep apnoea and the related intermittent hypoxia (IH) are widely recognised as risk factors for incident cardiovascular diseases. Numerous studies support... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Obstructive sleep apnoea and the related intermittent hypoxia (IH) are widely recognised as risk factors for incident cardiovascular diseases. Numerous studies support the deleterious vascular impact of IH in rodents but an overall interpretation is challenging owing to heterogeneity in rodent species investigated and the severity and duration of IH exposure. To clarify this major issue, we conducted a systematic review and meta-analysis to quantify the impact of IH on systemic artery structure and function depending on the different IH exposure designs.
METHODS
We searched PubMed, Embase and Web of Science, and included 125 articles in a meta-analysis, among them 112 using wild-type rodents and 13 using apolipoprotein E knockout (ApoE) mice. We used the standardised mean difference (SMD) to compare results between studies.
RESULTS
IH significantly increased mean arterial pressure (+13.90 (95% CI 11.88-15.92) mmHg), and systolic and diastolic blood pressure. Meta-regressions showed that mean arterial pressure change was associated with strain and year of publication. IH altered vasodilation in males but not in females and increased endothelin-1-induced but not phenylephrine-induced vasoconstriction. Intima-media thickness significantly increased upon IH exposure (SMD 1.10 (95% CI 0.58-1.62); absolute values +5.23 (2.81-7.84) µm). This increase was observed in mice but not in rats and was negatively associated with age. Finally, IH increased atherosclerotic plaque size in ApoE mice (SMD 1.08 (95% CI 0.80-1.37)).
CONCLUSIONS
Our meta-analysis established that IH, independently of other confounders, has a strong effect on vascular structure and physiology. Our findings support the interest of identifying and treating sleep apnoea in routine cardiology practice.
Topics: Animals; Blood Pressure; Carotid Intima-Media Thickness; Disease Models, Animal; Female; Humans; Hypoxia; Male; Mice; Rats; Rodentia
PubMed: 34413154
DOI: 10.1183/13993003.00866-2021 -
Minerva Anestesiologica Dec 2022Multiple studies have compared varying prophylactic and therapeutic doses of norepinephrine and phenylephrine given as either intermittent bolus or fixed-rate infusion... (Meta-Analysis)
Meta-Analysis
INTRODUCTION
Multiple studies have compared varying prophylactic and therapeutic doses of norepinephrine and phenylephrine given as either intermittent bolus or fixed-rate infusion to combat postspinal hypotension in patients undergoing cesarean section (CS). We conducted a systematic review to figure out the best alternative to treat postspinal hypotension.
EVIDENCE ACQUISITION
PubMed and Cochrane databases were extensively searched for eligible RCTs. A total of 15 studies were found eligible and analyzed for the incidence of maternal bradycardia as the primary outcome and other maternal adverse effects, fetal acidosis and Apgar scores at 1 and 5 min as the secondary outcome. Data was analyzed using Review Manager Version 5.3. software.
EVIDENCE SYNTHESIS
There was no significant difference in the efficacy of norepinephrine and phenylephrine for managing postspinal hypotension (OR=1.15 [95% CI: 0.91-1.45], P=0.24, I=0%,moderate quality) in parturients undergoing CS. Odds of incidence of maternal bradycardia decrease significantly by 61% with norepinephrine versus phenylephrine (OR=0.39 [95% CI: 0.31-0.49], P<0.00001, I=27%, high quality evidence). Significant higher umbilical artery mean pH values were observed with NE versus PE (MD=0.0 [95% CI: 0.00 to 0.01], P=0.03), although not clinical relevant. However, no significant difference was found in the incidence of other maternal adverse effects and fetal outcomes.
CONCLUSIONS
Comparable efficacy for management of postspinal hypotension, though, norepinephrine was found to cause less incidence of maternal bradycardia as compared to phenylephrine.
Topics: Humans; Pregnancy; Female; Phenylephrine; Cesarean Section; Norepinephrine; Anesthesia, Spinal; Bradycardia; Vasoconstrictor Agents; Hypotension; Anesthesia, Obstetrical; Double-Blind Method
PubMed: 35785931
DOI: 10.23736/S0375-9393.22.16654-X -
Acta Anaesthesiologica Scandinavica Nov 2016Adult critically ill patients often suffer from acute circulatory failure, necessitating use of vasopressor therapy. The aim of the Scandinavian Society of... (Review)
Review
BACKGROUND
Adult critically ill patients often suffer from acute circulatory failure, necessitating use of vasopressor therapy. The aim of the Scandinavian Society of Anaesthesiology and Intensive Care Medicine (SSAI) task force for Acute Circulatory Failure was to present clinically relevant, evidence-based treatment recommendations on this topic.
METHODS
This guideline was developed according to standards for trustworthy guidelines, including a systematic review of the literature and use of the GRADE methodology for assessment of the quality of evidence and for moving from evidence to recommendations. We assessed the following subpopulations of patients with acute circulatory failure: 1) shock in general, 2) septic shock, 3) cardiogenic shock, 4) hypovolemic shock and 5) other types of shock, including vasodilatory shock. We assessed patient-important outcome measures, including mortality, serious adverse reactions and quality-of-life.
RESULTS
For patients with shock in general and those with septic shock, we recommend using norepinephrine rather than dopamine, and we suggest using norepinephrine rather than epinephrine, vasopressin analogues, and phenylephrine. For patients with cardiogenic shock and those with hypovolemic shock, we suggest using norepinephrine rather than dopamine, and we provide no recommendations/suggestions of norepinephrine vs. epinephrine, vasopressin analogues, and phenylephrine. For patients with other types of shock, including vasodilatory shock, we suggest using norepinephrine rather than dopamine, epinephrine, vasopressin analogues, and phenylephrine.
CONCLUSIONS
We recommend using norepinephrine rather than other vasopressors as first-line treatment for the majority of adult critically ill patients with acute circulatory failure.
Topics: Acute Disease; Humans; Norepinephrine; Practice Guidelines as Topic; Shock; Vasoconstrictor Agents
PubMed: 27576362
DOI: 10.1111/aas.12780 -
Transplantation Apr 2024We conducted a systematic review and network meta-analyses evaluating the effects of different intraoperative vasoactive drugs on acute kidney injury (AKI) and other... (Meta-Analysis)
Meta-Analysis
We conducted a systematic review and network meta-analyses evaluating the effects of different intraoperative vasoactive drugs on acute kidney injury (AKI) and other perioperative outcomes in adult liver transplant recipients. We searched multiple electronic databases using words from the "liver transplantation" and "vasoactive drug" domains. We included all randomized controlled trials conducted in adult liver transplant recipients comparing 2 different intravenous vasoactive drugs or 1 against a standard of care that reported AKI, intraoperative blood loss, or any other postoperative outcome. We conducted 4 frequentist network meta-analyses using random effect models, based on the interventions' mechanism of action, and evaluated the quality of evidence (QoE) using Grading of Recommendations, Assessment, Development, and Evaluations recommendations. We included 9 randomized controlled trials comparing different vasopressor drugs (vasoconstrictor or inotrope), 3 comparing a somatostatin infusion (or its analogues) to a standard of care, 11 comparing different vasodilator infusions together or against a standard of care, and 2 comparing vasoconstrictor boluses at graft reperfusion. Intravenous clonidine was associated with shorter duration of mechanical ventilation, intensive care unit, and hospital length of stay (very low QoE), and some vasodilators were associated with lower creatinine level 24 h after surgery (low to very low QoE). Phenylephrine and terlipressin were associated with less intraoperative blood loss when compared with norepinephrine (low and moderate QoE). None of the vasoactive drugs improve any other postoperative outcomes, including AKI. There is still important equipoise regarding the best vasoactive drug to use in liver transplantation for most outcomes. Further studies are required to better inform clinical practice.
Topics: Adult; Humans; Liver Transplantation; Blood Loss, Surgical; Network Meta-Analysis; Vasoconstrictor Agents; Vasodilator Agents; Acute Kidney Injury
PubMed: 37525360
DOI: 10.1097/TP.0000000000004744 -
Frontiers in Pharmacology 2022Phenylephrine is the first-line drug used to maintain blood pressure in cesarean delivery. However, it poses a high risk of bradycardia and depression of cardiac...
Comparative efficacy and safety of prophylactic norepinephrine and phenylephrine in spinal anesthesia for cesarean section: A systematic review and meta-analysis with trial sequential analysis.
Phenylephrine is the first-line drug used to maintain blood pressure in cesarean delivery. However, it poses a high risk of bradycardia and depression of cardiac activity in pregnant women. Consequently, norepinephrine has gained popularity over the recent years, as an alternative to Phenylephrine because it is thought that prophylactic use of vasopressors may reduce the incidence of hypotension after spinal anesthesia. This systematic review compared the efficacy of both treatments. We searched the following databases; CNKI, PubMed, Embase, Web of science, clinicaltrials.gov, Medline and Cochrane Library, for randomized controlled trials comparing the prophylactic efficacy of norepinephrine and phenylephrine on elective cesarean delivery under spinal anesthesia. The search period was from inception to July 2022, and the primary outcome indicator was incidence of bradycardia. Statistical analysis was conducted on Rev manager 5.4, and the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) framework was used to evaluate the quality of evidence from each main finding. A total of 12 papers were included in the analysis. The incidence of bradycardia (RR = 0.37, 95% CI: 0.28 to 0.49, < 0.00001) and reactive hypertension (RR = 0.58, 95% CI 0.40 to 0.83, = 0.003) was significantly lower in the norepinephrine (NE) group compared with the phenylephrine (PE) category. In contrast, there were no statistical differences in the umbilical cord blood gas analysis pH values between the groups (arterial: MD = 0.00, 95% CI -0.00 to 0.01, = 0.22, vein: MD = 0.01, 95% CI -0.00 to 0.02, = 0.06). The incidence of hypotension, nausea, and vomiting did not differ significantly between the NE and PE groups (hypotension: 23% vs. 18%; nausea: 14% vs. 18%; vomiting: 5% vs. 7%, respectively). Prophylactic use of norepinephrine is safe and effective in maintaining maternal hemodynamics without causing adverse events to either the pregnant woman or fetus. website https://www.crd.york.ac.uk/prospero/, identifier CRD42022347095.
PubMed: 36518675
DOI: 10.3389/fphar.2022.1015325 -
The Cochrane Database of Systematic... Oct 2014It is unclear whether blood pressure should be altered actively during the acute phase of stroke. This is an update of a Cochrane review first published in 1997, and... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
It is unclear whether blood pressure should be altered actively during the acute phase of stroke. This is an update of a Cochrane review first published in 1997, and previously updated in 2001 and 2008.
OBJECTIVES
To assess the clinical effectiveness of altering blood pressure in people with acute stroke, and the effect of different vasoactive drugs on blood pressure in acute stroke.
SEARCH METHODS
We searched the Cochrane Stroke Group Trials Register (last searched in February 2014), the Cochrane Database of Systematic reviews (CDSR) and the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2014, Issue 2), MEDLINE (Ovid) (1966 to May 2014), EMBASE (Ovid) (1974 to May 2014), Science Citation Index (ISI, Web of Science, 1981 to May 2014) and the Stroke Trials Registry (searched May 2014).
SELECTION CRITERIA
Randomised controlled trials of interventions that aimed to alter blood pressure compared with control in participants within one week of acute ischaemic or haemorrhagic stroke.
DATA COLLECTION AND ANALYSIS
Two review authors independently applied the inclusion criteria, assessed trial quality and extracted data. The review authors cross-checked data and resolved discrepancies by discussion to reach consensus. We obtained published and unpublished data where available.
MAIN RESULTS
We included 26 trials involving 17,011 participants (8497 participants were assigned active therapy and 8514 participants received placebo/control). Not all trials contributed to each outcome. Most data came from trials that had a wide time window for recruitment; four trials gave treatment within six hours and one trial within eight hours. The trials tested alpha-2 adrenergic agonists (A2AA), angiotensin converting enzyme inhibitors (ACEI), angiotensin receptor antagonists (ARA), calcium channel blockers (CCBs), nitric oxide (NO) donors, thiazide-like diuretics, and target-driven blood pressure lowering. One trial tested phenylephrine.At 24 hours after randomisation oral ACEIs reduced systolic blood pressure (SBP, mean difference (MD) -8 mmHg, 95% confidence interval (CI) -17 to 1) and diastolic blood pressure (DBP, MD -3 mmHg, 95% CI -9 to 2), sublingual ACEIs reduced SBP (MD -12.00 mm Hg, 95% CI -26 to 2) and DBP (MD -2, 95%CI -10 to 6), oral ARA reduced SBP (MD -1 mm Hg, 95% CI -3 to 2) and DBP (MD -1 mm Hg, 95% CI -3 to 1), oral beta blockers reduced SBP (MD -14 mm Hg; 95% CI -27 to -1) and DBP (MD -1 mm Hg, 95% CI -9 to 7), intravenous (iv) beta blockers reduced SBP (MD -5 mm Hg, 95% CI -18 to 8) and DBP (-5 mm Hg, 95% CI -13 to 3), oral CCBs reduced SBP (MD -13 mmHg, 95% CI -43 to 17) and DBP (MD -6 mmHg, 95% CI -14 to 2), iv CCBs reduced SBP (MD -32 mmHg, 95% CI -65 to 1) and DBP (MD -13, 95% CI -31 to 6), NO donors reduced SBP (MD -12 mmHg, 95% CI -19 to -5) and DBP (MD -3, 95% CI -4 to -2) while phenylephrine, non-significantly increased SBP (MD 21 mmHg, 95% CI -13 to 55) and DBP (MD 1 mmHg, 95% CI -15 to 16).Blood pressure lowering did not reduce death or dependency either by drug class (OR 0.98, 95% CI 0.92 to 1.05), stroke type (OR 0.98, 95% CI 0.92 to 1.05) or time to treatment (OR 0.98, 95% CI 0.92 to 1.05). Treatment within six hours of stroke appeared effective in reducing death or dependency (OR 0.86, 95% CI 0.76 to 0.99) but not death (OR 0.70, 95% CI 0.38 to 1.26) at the end of the trial. Although death or dependency did not differ between people who continued pre-stroke antihypertensive treatment versus those who stopped it temporarily (worse outcome with continuing treatment, OR 1.06, 95% CI 0.91 to 1.24), disability scores at the end of the trial were worse in participants randomised to continue treatment (Barthel Index, MD -3.2, 95% CI -5.8, -0.6).
AUTHORS' CONCLUSIONS
There is insufficient evidence that lowering blood pressure during the acute phase of stroke improves functional outcome. It is reasonable to withhold blood pressure-lowering drugs until patients are medically and neurologically stable, and have suitable oral or enteral access, after which drugs can than be reintroduced. In people with acute stroke, CCBs, ACEI, ARA, beta blockers and NO donors each lower blood pressure while phenylephrine probably increases blood pressure. Further trials are needed to identify which people are most likely to benefit from early treatment, in particular whether treatment started very early is beneficial.
Topics: Acute Disease; Blood Pressure; Calcium Channel Blockers; Humans; Hypertension; Randomized Controlled Trials as Topic; Risk; Stroke; Time-to-Treatment; Vasodilator Agents
PubMed: 25353321
DOI: 10.1002/14651858.CD000039.pub3 -
Near-Infrared Spectroscopy in Adult Cardiac Surgery Patients: A Systematic Review and Meta-Analysis.Journal of Cardiothoracic and Vascular... Aug 2017To identify the normal baseline preoperative range of cerebral tissue oxygen saturation (SctO) derived using near-infrared spectroscopy (NIRS) and the efficacy of... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVES
To identify the normal baseline preoperative range of cerebral tissue oxygen saturation (SctO) derived using near-infrared spectroscopy (NIRS) and the efficacy of perioperative interventions designed to modulate SctO in cardiac surgical patients.
DESIGN
Systematic review and meta-analysis of relevant randomized controlled trials (RCTs) extracted from the Medline, Embase, and Cochrane Central Register of Controlled Trials databases.
SETTING
Hospitals performing cardiac surgery.
PARTICIPANTS
The study comprised 953 participants from 11 RCTs.
INTERVENTIONS
Interventions included the following: (1) SctO monitoring protocol compared with no monitoring; (2) use of cardiopulmonary bypass (CPB) compared with no CPB; (3) normothermic CPB compared with hypothermic CPB; (4) glyceryl trinitrate during surgery compared with placebo; (5) midazolam during induction of anesthesia compared with propofol; (6) sevoflurane anesthesia compared with total intravenous anesthesia; (7) sevoflurane anesthesia compared with propofol-based anesthesia; and (8) norepinephrine during CPB compared with phenylephrine.
MEASUREMENTS AND MAIN RESULTS
Eleven RCTs with 953 participants measured baseline preoperative SctO using NIRS. The pooled mean baseline SctO was 66.4% (95% CI 65.0-67.7), generating a reference range of 51.0% to 81.8%. Four interventions (1, 3, 4, and 6 described in the Interventions section above) increased intraoperative SctO across the majority of reported time points. Postoperative follow-up of SctO occurred in only 1 study, and postoperative cognitive assessment correlating SctO with cognitive function was applied in only 4 studies using variable methodology.
CONCLUSIONS
The authors have established that reference values for baseline NIRS-derived SctO in cardiac surgery patients are varied and have identified interventions that modulate SctO. This information opens the door to standardized research and interventional studies in this field.
Topics: Brain; Cardiac Surgical Procedures; Cardiovascular Diseases; Humans; Oxygen Consumption; Randomized Controlled Trials as Topic; Spectroscopy, Near-Infrared
PubMed: 28800981
DOI: 10.1053/j.jvca.2017.02.187 -
JBI Evidence Synthesis Jan 2021The objective of this review was to examine the effect of phenylephrine on cerebral oxygen saturation, cardiac output, and middle cerebral artery blood flow velocity...
OBJECTIVE
The objective of this review was to examine the effect of phenylephrine on cerebral oxygen saturation, cardiac output, and middle cerebral artery blood flow velocity when used to treat intraoperative hypotension.
INTRODUCTION
While the etiology of postoperative cognitive dysfunction in adults following surgery is likely multifactorial, intraoperative cerebral hypoperfusion is a commonly proposed mechanism. Research evidence and expert opinion are emerging that suggest phenylephrine adversely affects cerebral oxygen saturation and may also adversely affect cerebral perfusion via a reduction in cardiac output or cerebral vascular vasoconstriction. The administration of phenylephrine to treat intraoperative hypotension is common anesthesia practice, despite a lack of evidence to show it improves cerebral perfusion. Therefore, a systematic review of the effect of phenylephrine on cerebral hemodynamics has significant implications for anesthesia practice and future research.
INCLUSION CRITERIA
Studies of adults 18 years and over undergoing elective, non-neurosurgical procedures involving anesthesia were included. In these studies, participants received phenylephrine to treat intraoperative hypotension. The effect of phenylephrine on cerebral oxygen saturation, cardiac output, or middle cerebral artery blood flow velocity was measured.
METHODS
Key information sources searched included MEDLINE (Ovid), Embase, CINAHL (EBSCO), and Google Scholar. The scope of the search was limited to English-language studies published from 1999 through 2017. The recommended JBI approach to critical appraisal, study selection, data extraction, and data synthesis were used.
RESULTS
This systematic review found that phenylephrine consistently decreased cerebral oxygen saturation values despite simultaneously increasing mean arterial pressure to normal range. Results also found that ephedrine and dopamine were superior to phenylephrine in maintaining or increasing values. Phenylephrine was found to be similar to vasopressin in the extent to which both decreased cerebral oxygen saturation values. Results also showed that phenylephrine resulted in statistically significant declines in cardiac output, or failed to improve abnormally low preintervention values. The effect of phenylephrine on middle cerebral artery blood flow velocity was only measured in one study and showed that phenylephrine increased flow velocity by about 20%. Statistical pooling of the study results was not possible due to the gross variation in how the intervention was administered and how effect was measured.
CONCLUSIONS
This review found that phenylephrine administration resulted in declines in cerebral oxygen saturation and cardiac output. However, the research studies were ineffective in informing phenylephrine's mechanism of action or its impact on postoperative cognitive function.
SYSTEMATIC REVIEW REGISTRATION NUMBER
PROSPERO (CRD42018100740).
Topics: Adolescent; Adult; Cardiac Output; Humans; Hypotension; Oxygen; Phenylephrine; Vasoconstrictor Agents
PubMed: 32941358
DOI: 10.11124/JBISRIR-D-19-00352