Arterial Stiffness and General Anesthesia Induced Hypotension in Patients on Angiotensin-converting Enzyme Inhibitors

NCT02416024 | Completed

• 1 other identifier: 201308815
• Study Type: observational
• Target: 72
• Locations: 1 country
• Sites: 1

Brief Summary

Induction of general anesthesia to the patient could be a challenging period of anesthesia management. Due to autonomic system suppression, hemodynamic fluctuation, such as hypotension or hypertension, is commonly seen during this period. Furthermore, it has been observed that a fraction of patients who develop hypotension may be refractory to vasoactive medications to attempt to restore the systemic arterial blood pressure back to an acceptable level. Previous studies have shown that patients chronically taking angiotensin converting enzyme (ACE) inhibitors have a higher incidence of developing hypotension under general anesthesia as well as being refractory to adrenergic vasoconstrictor medications given to help restore systemic blood pressure. Interestingly, not all patients taking ACE inhibitors have shown the described hemodynamic response after induction of general anesthesia. Therefore, investigators are attempting to identify what changes in vascular physiology in those patients may contribute to acute refractory systemic hypotension. Specifically, investigators wish to explore whether differences in baseline levels of arterial stiffness potentially contribute to this phenomenon. Arterial applanation tonometry is a non-invasive technique that has been shown to reliably provide indices of arterial stiffness. In the proposed project, applanation tonometry will be performed on the right carotid and femoral arteries to assess carotid-femoral pulse wave velocity, a surrogate for aortic stiffness. (SphygmoCor system, AtCor Medical, Sydney, Australia) The measurement will be obtained before induction of general anesthesia in the pre-surgical area. During induction of general anesthesia with standard induction agents, brachial blood pressure will be measured by a cuff every minute up to 10 minutes after tracheal intubation. A hypotensive response to anesthesia will be defined by a systolic arterial blood pressure below 90mmHg upon induction. Hypotensive patients that do not respond to vasoconstrictor medications (i.e. requires more than 200 mcg phenylephrine to maintain systolic arterial blood pressure above 90 mmHg) will be classified as 'refractory hypotensive." Using non-invasive applanation tonometry, we will be able to examine if aortic stiffness has a propensity to become refractory hypotension after induction of general anesthesia. This information will potentially help identify future patients that might be at greater risk of developing refractory hypotension in response to induction of general anesthesia.

Conditions

Hypotension; Arterial Stiffness

Keywords

angiotensin converting enzyme inhibitor; anesthesia

Outcome Measures

Primary Outcomes (1)

• Comparison of Vascular Stiffness between refractory hypotension and non-refractory hypotension group

  The study is aimed to compare arterial stiffness between patients develop refractory hypotension and do not develop refractory hypotension after administration of anesthetics in preparation for surgery of patients older than 60 years of age and with a prescription/current use of ACE-inhibitors. Arterial stiffness will be measured by pulse wave velocity (m/s) with a SphygmoCor® device (Atcor, Sydney, Australia)

  within one hour

Study Arms (2)

No Refractory hypotension group

Patient who did not require more than 200 mcg of phenylephrine to maintain systemic blood pressure during 10 minutes after induction of general anesthesia.

Device: SphygmoCor system

Control

Patient who required more than 200 mcg of phenylephrine to maintain systemic blood pressure during 10 minutes after induction of general anesthesia

Device: SphygmoCor system

Interventions

SphygmoCor system DEVICE

Carotid-femoral pulse wave velocity (cfPWV) will be determined by applanation tonometry using the Sphygmocor system by sequentially recording ECG-gated carotid and femoral artery waveforms. Pulse wave signals will be recorded by tonometers positioned at the base of the right common carotid artery and over the right femoral artery. The time (t) between the feet of simultaneously recorded waves will be determined as the mean of 10 consecutive cardiac cycles. PWV is calculated by the system software from the distance between measurement points (D) and the measured time delay (t) as follows: cfPWV = D/Δt (m/s) where D is distance in meters and t is the time interval in seconds.

Control; No Refractory hypotension group

Eligibility Criteria

• Age: 50 Years - 85 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Patient who are going under surgery with age between 50 - 85

You may qualify if:

• There will be three study populations. The first study population will include 60 adult patients over 50 years old and on ACE inhibitors for more than 3 months, scheduled for surgery under general anesthesia in the second case in the Main Operating Room at the UIHC. Patients who are taking angiotensin receptor inhibitors will not be enrolled for the study.
• The second study population will include 20 adult patients over 50 years old who are not taking an ACE inhibitor and are currently taking a beta blocker, a calcium channel blocker, or a diuretic for more than 3 months, scheduled for surgery under general anesthesia in the Main Operating Room at the UIHC.

You may not qualify if:

• We will exclude patients with diabetes (on insulin therapy), renal insufficiency (Cr\>2.0), history of arterial bypass (i.e. F-F bypass), history of carotid endoarterectomy, angiotensin receptor inhibitor medication, heart rate \<40 bpm or \>100 bpm, atrial fibrillation/flutter, history of ischemic stroke, transient ischemic attack, myocardial infarction or coronary revascularization (any type) within 6 months, known left main or 3-vessel coronary disease positive myocardial perfusion study without subsequent revascularization, angina or heart failure (\>3 NYHA) class 3, known left ventricle ejection fraction \<30%, pulmonary hypertension (PA systolic \>50mmHg), right ventricle dysfunction, or a preoperative systolic blood pressure of \>180 mmHg or \<110 mmHg within 1 month prior to surgery.

Sponsors & Collaborators

• University of Iowa: lead

Study Sites (1)

University of Iowa Hospitals and Clinics

Iowa City, Iowa, 52242, United States

Location

Related Publications (7)

• Gasecki D, Rojek A, Kwarciany M, Kowalczyk K, Boutouyrie P, Nyka W, Laurent S, Narkiewicz K. Pulse wave velocity is associated with early clinical outcome after ischemic stroke. Atherosclerosis. 2012 Dec;225(2):348-52. doi: 10.1016/j.atherosclerosis.2012.09.024. Epub 2012 Oct 3.

  PMID: 23083680 RESULT

• Mitchell GF, Hwang SJ, Vasan RS, Larson MG, Pencina MJ, Hamburg NM, Vita JA, Levy D, Benjamin EJ. Arterial stiffness and cardiovascular events: the Framingham Heart Study. Circulation. 2010 Feb 2;121(4):505-11. doi: 10.1161/CIRCULATIONAHA.109.886655. Epub 2010 Jan 18.

  PMID: 20083680 RESULT

• Blann AD, Kuzniatsova N, Lip GY. Inflammation does not influence arterial stiffness and pulse-wave velocity in patients with coronary artery disease. J Hum Hypertens. 2013 Oct;27(10):629-34. doi: 10.1038/jhh.2013.17. Epub 2013 Mar 28.

  PMID: 23535991 RESULT

• Ozturk S, Baltaci D, Ayhan SS, Durmus I, Gedikli O, Soyturk M, Yazici M, Celik S. Assessment of the relationship between aortic pulse wave velocity and aortic arch calcification. Turk Kardiyol Dern Ars. 2012 Dec;40(8):683-9. doi: 10.5543/tkda.2012.83707.

  PMID: 23518881 RESULT

• Dangardt F, Chen Y, Berggren K, Osika W, Friberg P. Increased rate of arterial stiffening with obesity in adolescents: a five-year follow-up study. PLoS One. 2013;8(2):e57454. doi: 10.1371/journal.pone.0057454. Epub 2013 Feb 22.

  PMID: 23451232 RESULT

• Nordstrand N, Gjevestad E, Hertel JK, Johnson LK, Saltvedt E, Roislien J, Hjelmesaeth J. Arterial stiffness, lifestyle intervention and a low-calorie diet in morbidly obese patients-a nonrandomized clinical trial. Obesity (Silver Spring). 2013 Apr;21(4):690-7. doi: 10.1002/oby.20099.

  PMID: 23712971 RESULT

• Alecu C, Cuignet-Royer E, Mertes PM, Salvi P, Vespignani H, Lambert M, Bouaziz H, Benetos A. Pre-existing arterial stiffness can predict hypotension during induction of anaesthesia in the elderly. Br J Anaesth. 2010 Nov;105(5):583-8. doi: 10.1093/bja/aeq231. Epub 2010 Aug 26.

  PMID: 20798172 RESULT

MeSH Terms

Conditions

Hypotension

Condition Hierarchy (Ancestors)

Vascular Diseases; Cardiovascular Diseases

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Clinical Associate Professor

Study Record Dates

• First Submitted: April 6, 2015
• First Posted: April 14, 2015
• Study Start: August 1, 2013
• Primary Completion: June 1, 2018
• Study Completion: September 1, 2018
• Last Updated: March 18, 2019

Record last verified: 2019-03

Locations

US (1)