Intraoperative hypotension in elder patients (IHypE)

ISRCTN ISRCTN38968048
DOI https://doi.org/10.1186/ISRCTN38968048
Secondary identifying numbers 31771
Submission date
02/05/2017
Registration date
02/05/2017
Last edited
26/11/2019
Recruitment status
No longer recruiting
Overall study status
Completed
Condition category
Circulatory System
Prospectively registered
Protocol
Statistical analysis plan
Results
Individual participant data
Record updated in last year

Plain English summary of protocol

Background and study aims
Low blood pressure during surgery (also known as intraoperative hypotension or IOH) is thought to be very common. It happens as a side effect of the medicines used during anaesthesia (sedation during surgery). In patients aged over 65 years, this may lead to an increased risk heart attack, stroke, kidney failure and death following surgery. This risk increases as the degree and duration of low blood pressure increases. Patients aged over 65 years are at increased risk because their body is less able to cope with low blood pressure. Finding out how common IOH is can be difficult, as there is no clear and universally accepted definition. The purpose of this study is twofold. Firstly to determine how often low blood pressure occurs during operations in elderly patients in the UK and whether this is linked to a higher risk of complications. Secondly, to determine how and why anaesthetists treat low blood pressure during operations.

Who can participate?
Patients aged 65 years or older and having surgery under anaesthesia

What does the study involve?
Taking part in this study does not change the care patients would receive if they were not taking part. The researchers review the anaesthetic charts of participants undergoing surgery and record instances of IOH, as well as how serious it is and how long it lasts. Other key medical and background information is also recorded for each patient. Patients included in the study are followed up to assess their recovery up to 30 days after surgery. All information is obtained from patient records rather than face-to-face encounters. Anaesthetists, who looked after a participant, are given a questionnaire asking about individual practice in relation to the treatment of low blood pressure during surgery. The responses are collected and assessed to determine national consensus on this topic.

What are the possible benefits and risks of participating?
There are no notable benefits or risks involved with participating.

Where is the study run from?
University College Hospital and 200 of NHS hospitals (UK)

When is the study starting and how long is it expected to run for?
June 2015 to June 2017

Who is funding the study?
National Institute of Academic Anaesthesia (UK)

Who is the main contact?
Dr Alex Wickham
alex.wickham@nhs.net

Study website

Contact information

Dr Alex Wickham
Scientific

Imperial School of Anaesthesia
London
SW7 2AZ
United Kingdom

Phone +44 7734 819931
Email alex.wickham@nhs.net

Study information

Study designObservational; Design type: Cohort study
Primary study designObservational
Secondary study designCohort study
Study setting(s)Hospital
Study typeOther
Participant information sheet ISRCTN38968048_PIS_07Aug16_V2.2.pdf
Scientific titleIntraoperative Hypotension in Elder Patients (IHypE): an observational study of intraoperative hypotension in patients aged over 65 in UK hospitals
Study acronymIHypE
Study objectivesThe aim of this study is to determine how often low blood pressure occurs during operations in elderly patients in the UK and whether this is linked to a higher risk of complications, and to investigate how and why anaesthetists treat low blood pressure during operations.
Ethics approval(s)West London & GTAC Research Ethics Committee, 09/08/2016, ref: 16/LO/1154
Health condition(s) or problem(s) studiedSpecialty: Anaesthesia, perioperative medicine and pain management, Primary sub-specialty: Anaesthesia, Perioperative Medicine and Pain Management; UKCRC code/ Disease: Other/ General symptoms and signs
InterventionPatient Participants: No direct intervention is made as part of the study. Patient anaesthetic records are examined and data on pre-morbid health state and intraoperative blood pressure is collected. 30 day outcome data (mortality, troponin, creatinine and ischaemic stroke).

Anaesthetist participants: Anaesthetists who have anaesthetised a patient who meets the inclusion criteria will be asked to complete a short survey assessing their opinions on intraoperative hypotension in patients aged over 65 years.
Intervention typeOther
Primary outcome measureProportion of elderly patients developing intraoperative hypotension (IOH), the percentage drop from baseline blood pressure and the duration of hypotension. IOH will be recorded from reviewing the patients anaesthetic chart within 24 hours of having surgery. Percentage drop from baseline will be calculated using baselines of pre-induction and pre-operative blood pressure and the lowest recorded value. Duration of IOH will be calculated as the time in minutes spent consecutively at or within 5mmHg of the lowest value recorded on the anaesthetic chart.
Secondary outcome measures1. In hospital mortality at 30 days: assessed by review of the clinical record
2. Acute kidney injury within 7 days of surgery: defined as a postoperative creatinine increase ≥1.5 times the baseline value or ≥26.5μmol/L. Assessed by review of the clinical record
3. Myocardial injury: Defined as a postoperative troponin enzyme concentration within 7 days of surgery that is above the 99th percentile of the upper reference limit. Assessed by review of the clinical record
4. Stroke, defined as an ischaemic stroke reported from a computed tomography (CT) scan of the brain within 7 days of surgery. Assessed by review of the clinical record
5. Anaesthetist perceptions of and treatment thresholds for hypotension is determined by assessment of a questionnaire administered on the date of participant recruitment
Overall study start date01/06/2015
Completion date01/06/2017

Eligibility

Participant type(s)Patient
Age groupAdult
SexBoth
Target number of participantsPlanned Sample Size: 1700; UK Sample Size: 300
Key inclusion criteria1. Aged >65 years
2. Underwent general anaesthesia or regional anaesthesia either alone or in combination in an operating theatre
3. Emergency and elective surgery
Key exclusion criteria1. Procedure requires cardiopulmonary bypass
2. The patient undergoes sedation alone (that is, not in combination with regional anaesthesia)
Date of first enrolment21/11/2016
Date of final enrolment31/01/2017

Locations

Countries of recruitment

  • England
  • United Kingdom

Study participating centre

University College Hospital
University College London Hospitals NHS Foundation Trust
Euston Road
London
NW1 2PG
United Kingdom

Sponsor information

University College London
University/education

Joint Research Office
Gower Street
London
WC1E 6BT
England
United Kingdom

Phone +44 20 3447 7428
Email Cameron.Berg@ucl.ac.uk
ROR logo "ROR" https://ror.org/02jx3x895

Funders

Funder type

Government

National Institute of Academic Anaesthesia

No information available

Results and Publications

Intention to publish date31/12/2017
Individual participant data (IPD) Intention to shareNo
IPD sharing plan summaryNot expected to be made available
Publication and dissemination plan1. Planned presentation of selected abstracts from the study data at the British Journal of Anaesthesia/ Anaesthetic Research Society 2017 Spring meeting (London), Euroanaesthesia 2017 (Geneva) and the ANZCA ASM 2017 (Brisbane)
2. Planned publication in a high impact peer reviewed Anaesthetic journal by December 2017
IPD sharing planThe datasets generated during and/or analysed during the current study are not expected to be made available because the participants did not provide consent to disseminate participant level data.

Study outputs

Output type Details Date created Date added Peer reviewed? Patient-facing?
Participant information sheet version V2.2 07/08/2016 11/05/2017 No Yes
HRA research summary 28/06/2023 No No

Additional files

ISRCTN38968048_PIS_07Aug16_V2.2.pdf
Uploaded 11/05/2017

Editorial Notes

25/11/2019: No publications found. Verifying results with principal investigator.
08/11/2017: The ISRCTN prospective/retrospective flag compares the date of registration with the recruitment start date and does not include any grace period. The registration of this study was requested through the NIHR Portfolio and was finalised within 6 months of the recruitment starting.
11/05/2017: The participant information sheet has been uploaded