Preoperative optimisation of chronic medical conditions in Primary Care.

INTRODUCTION

This summary document outlines some perioperative thresholds for chronic medical conditions to assist identification/optimisation in primary care before referral for elective surgery. Full details of our preoperative guidelines can be found at

These thresholds apply to elective surgery ONLY. If surgery is urgent, then there is often inadequate time to optimise comorbidities and appropriate steps will be taken to mitigate the associated risks perioperatively.

We have found the most common reasons for requiring postponement include:

  1. Anaemia (Hb<130g/L(male) or <120g/L (female)) (intermediate/major surgery)
  1. Uncontrolled hypertension (>/=160mmHg/100mmHg in primary care)
  1. Poorly controlled diabetes (HbA1c/=69mmol/mol)
  1. High risk of obstructive sleep apnoea (‘STOP BANG’ screening result 5/8 or more)
  1. New atrial fibrillation

This document will address the above issues, but will hopefully be expanded to include others in the future.

Please contact the RBH preoperative assessment clinic with any queries on 0118 322 6546

Dr. Simon Tunstill, Consultant Anaesthetist, RBH - April 2017

1. ANAEMIA

NICE guidelines recommend measurement of Haemaglobin (Hb) for patients with cardiovascular and renal disease undergoing intermediate surgery, and all patients under going major surgery.

Preoperative anaemia is an independent risk factor for adverse perioperative outcomes. Patientsreferred for elective intermediate/major surgery should ideally have:

Hb >130g/L (males), or >120g/L (females)

If the patient remains anaemic despite appropriate investigation and treatment in primary care, this information should be included with the referral.

References:

NICE – routine preoperative tests for elective surgery (April 2016)

Association of Anaesthetists of Great Britain and Ireland.The use of blood components and their alternatives. 2016

RBH guideline – Management of anaemia prior to major surgery. May 2016

2. HYPERTENSION

Patients for elective surgery should be referred with mean blood pressures recorded in primary care in the past 12 months of <160/100mmHg. This information should be provided at the time of referral. (Investigations and treatment should continue in primary care to achieve blood pressure measurements of <140/90mmHg as per NICE guidelines)

Patients with blood pressures >/=160/100mmHg or above in primary care should be assessed with ambulatory or home blood pressure monitoring and treated if necessary to reduce blood pressure to <160/100mmHg prior to referral for elective surgery.

Patients may be referred for elective surgery if they remain hypertensive despite optimal antihypertensive treatment or if they decline antihypertensive treatment. Please include this information with the referral.

References:

Association of Anaesthetists of Great Britain and Ireland guideline: The measurement of adult blood pressure and management of hypertension before elective surgery. January 2016

RBH guideline GL1022 – Management of arterial hypertension before elective surgery. June 2016

3. DIABETES

Diabetic control should be optimisedprior to elective surgery, aiming for HbA1c<69mmol/mol, to reduce perioperative complications.

Glycaemic control should be checked at the time of referral for surgery. Information about duration, type of diabetes, current treatment and complications should be made available to the secondary care team.

If the HbA1c is greater than 69mmol/mol, every effort should be made to improve control. For frail elderly patients, or patients with multiple comorbiditiesat risk of hypoglycaemia, a higher upper limit of 75mmol/mol may be appropriate.

  • For patients currently under a secondary care team, the referring primary care physician should communicate directly with this team for advice
  • For patients managed in the community, the referring primary care physician can refer/communicate with: a community endocrinology consultants, community diabetic specialist nurse or secondary care physician if required.

This information should be included in the referral for surgery

If the HbA1c remains high despite specialist opinion, the GP should make an active decision with the patient that all possible avenues for improvement have been explored and should communicate this, along with any interventions/referrals to the anaesthetic department. As different surgical procedures carry different risks, the decision to proceed with poorly controlled diabetes will lie with the surgeon and anaesthetist.

References:

Association of Anaesthetists of Great Britain and Ireland Guideline: Peri-operative management of the surgical patients with diabetes. September 2015

RBH guideline GL059 – Perioperative management of the surgical patient with diabetes. April 2016.

4. OBSTRUCTIVE SLEEP APNOEA

Obstructive sleep apnoea (OSA) is associated with increased adverse perioperative outcomes.

There are several screening tools designed to identify those at risk of obstructive sleep apnoea. At the RBH we use ’STOP BANG’. The patient scores a point for each of the following positive responses. If the total score is 5 or more, the patient is deemed at risk of moderate or severe OSA and requires sleep studies prior to elective surgery. We routinely screen for OSA at preoperative assessment and organize sleep studies if necessary, but we would be grateful if you could inform the patient that it may delay their date of surgery should you happen to identify anyone who fits these criteria.

Snoring – can snoring be heard through a closed door?

Tired – does the patient often feel tired in the daytime?

Observed – has the patient been observed by someone else to stop breathing?

Pressure – is the patient treated for, does he/she have hypertension?

BMI - >35kgm-2

Age – 50 years

Neck – circumference>40cm

Gender – Male

Reference:

RBH guideline GL068 – Assessment for obstructive sleep apnoea

5. NEW ATRIAL FIBRILLATION

NICE guidelines recommend restingelectrocardiograms for those with cardiovascular disease, renal disease, diabetes or any other severe systemic disease undergoing intermediate or major surgery; and anyone over 65 years undergoing major surgery.

Appropriate patients will have screening ECGs done at preoperative assessment and those with previously undiagnosed atrial fibrillation will require echocardiography to assess left ventricular function prior to referral for elective surgery. If you happen to diagnose new atrial fibrillation, requesting an echo and investigating for reversible causes prior to referral for elective surgery would be much appreciated and will speed up the patient’s surgical pathway.

References:

NICE – routine preoperative tests for elective surgery (April 2016)