AAGBI/Anaesthesia Research Grant

Royal Free Hospital, London

Title
Intraoperative Hypotension in the Elderly: Observational Study of Intraoperative Hypotension in Elder Patients in UK Hospitals (iHypE)

Amount
£9,076

Scientific Abstract
Intraoperative hypotension (IOH) is a potentially avoidable complication of anaesthesia associated with stroke, acute kidney injury, myocardial infarction, and mortality in older patients. Better control of intraoperative blood pressure may have the potential to improve perioperative outcomes. Defining current UK practice is a crucial step towards future research into improving intraoperative blood pressure management. We aim to determine the prevalence, magnitude, duration and treatment thresholds for IOH in patients aged >65 undergoing surgery in the UK. We hypothesize that IOH is widely prevalent and may be in part a disparity between the clinically applied treatment threshold and literature definitions for IOH. A 30 day observational study will be delivered entirely by regional trainee led research groups affiliated to the Research and Audit Federation of Trainees (RAFT). Episodes of IOH will be determined from anaesthetic records and compared with a clinician survey on treatment thresholds. The results from this large-scale project will generate a true representation of practice across the UK, highlighting the prevalence of IOH amongst older patients undergoing surgery, and power a future interventional study.

University of Nottingham

Title
The impact of blood pressure thresholds on perioperative mortality in non-cardiac surgery in a United Kingdom database

Amount
£37,218

Scientific Abstract
There are limited data informing the perioperative care of hypertensive patients. Blood pressure (BP) values associated with increased perioperative mortality and morbidity are poorly defined, and optimal preoperative medication for reducing perioperative risk remains unknown. Meta-analysis provided inconclusive evidence of increased perioperative risk. However, our large retrospective cohort analysis demonstrated that hypertension is not associated with increased postoperative mortality. Rather, preoperative hypotension (systolic BP<119 or diastolic <63) predicted increased mortality. This effect was robust to adjustment for 29 confounders using logistic regression and when restricted to the elderly. Furthermore, preoperative cardiovascular medications exerted disparate effects on postoperative mortality: loop diuretics increased risk in the hypotensive group, and statins and thiazides reduced risk in patients with systolic BP>140 mmHg. Herein, we seek to extend these findings by: (1) identifying the effect of preoperative BP and preoperative medications designed to modulate cardiovascular risk on measures of postoperative morbidity that may be used as endpoints in randomized controlled trials (acute coronary syndrome and stroke) and (2) identifying the contribution of preoperative blood pressure variability on postoperative mortality, acute coronary syndrome and stroke. Our aim is to provide preliminary data for a randomized controlled trial of preoperative BP stratification to modulate perioperative outcomes.

Leicester General Hospital

Title
The incidence of chronic headache and low back pain after accidental dural puncture with a Tuohy needle and epidural blood patch in the obstetric population: a prospective 2-group cohort study

Amount
£23,535

Scientific Abstract

Background
Neuraxial technique is the commonest mode of providing analgesia during labour and a well-recognised complication of this technique is accidental dural puncture (ADP). ADP can result in a postdural puncture headache that can result in significant distress and suffering to the parturient. The gold standard in the management of PDPH is an epidural blood patch. It is generally accepted that PDPH is a self-limiting condition. There is emerging evidence that PDPH can result in the development of chronic headaches and epidural blood patches could cause new onset chronic low back pain. There are no prospective clinical trial evaluating the incidence of chronic headache and low back pain following accidental dural puncture.

Aim
To evaluate the incidence of chronic headaches and new onset low back pain at 6, 12 and 18 months following accidental dural puncture in parturients.

Methods
Prospective, multicentre, prospective 2-group cohort study. Index patients will be matched with controls (1:2) for age, body mass index and delivered within four weeks of the index patient. The participants will complete two questionnaires at 6, 12 and 18 months following ADP. Participation will end 18 months after completion of the study questionnaires. The study duration is 36 months.

Royal Sussex County Hospital

Title
Pressure Area Distribution On A Variety Of Clinical Surfaces In A Group Of Volunteers

Amount
£2,272

Scientific Abstract

Pressure area damage is a significant cause of mortality and morbidity in the inpatient environment. It can occur when the pressure applied to an area of tissue exceeds its mean capillary perfusion pressure, approximately 17 mmHg. Pressure advisory groups have estimated that 45% of pressure ulcer damage is attributable to patients' time in operating theatres, yet there is a lack of data regarding pressure area distribution in this setting. We propose a pilot study involving 50 volunteers with a range of weights and Body Mass Index (BMI), undergoing simulated scenarios on commonly used clinical surfaces designed to mimic an acute inpatient admission, including surgery. Proposed scenarios include lying supine on a "spinal scoop", supine and lateral positions on an operating table, and the lithotomy position. Volunteers will lay immobile in each position for a period of 30 minutes, during which their pressure area distributions will be measured with a XSENSOR X3 PRO Pressure Mapping System, positioned between them and the clinical surface they are recumbent on. Peak pressures, mean pressures and pressure area distribution will be analysed and discussed with descriptive statistics, with the findings reviewed by our own Hospital and disseminated to the wider scientific community for discussion.