The essentials of good day surgery

In order to achieve good results in day surgery and avoid the pitfalls described above the following are essential:

selection of appropriate procedures and patients;

• preadmission assessment and information;

anaesthesia and surgery with minimal morbidity and complications;

postoperative and postdischarge analgesia;

discharge criteria and postoperative instructions;

follow-up and audit.

Day surgery selection

The aim of day surgery selection is to avoid predictable complications and morbidity. In selecting suitable procedures and patients, consider:

  the procedure to be undertaken;

the social circumstances;

the fitness of the patient.

Criteria for suitable day-case procedures

Minimal physiological trespass;

  not associated with excessive blood loss or fluid shifts;

  very low risk of serious postoperative complications (e.g. bleeding or airway obstruction);

  duration of up to 1 hour, 2 hours maximum;

pain must be controllable with oral analgesics after discharge;

  the patient should be reasonably ambulant afterwards.

  The use of surgical drains is controversial; if needed, these are removed before the patient goes home. Urinary catheters are surprisingly well tolerated and may allow urology patients to go home. Absorbable sutures and improved wound closure methods may reduce the need for patients to return for stitch removal.

Relatively uncontroversial day-case procedures (Table 69.5) make up the bulk of day surgery. However, other more major operations may now be included as minimally invasive surgical techniques using laparoscopy and lasers reduce post­operative problems and pain. Open abdominal, intrathoracic, intracranial and major vascular procedures are still universally considered to be unsuitable.  

In general, longer and more invasive operations are associated with more pain, bleeding or other complications, although this is not absolutely true — some may simply be time-consuming without increasing morbidity. Laparoscopic surgery in particular is associated with increased morbidity and overnight admission, particularly for procedures such as cholecystectomy. Tonsillectomy is also controversial: while routinely performed on a day-case basis in many centres, anxiety about the risk of bleeding deters others. The pathology is important — small haemorrhoids or incisional hernias are suitable, very large ones may not be.

The push to ambulatory surgery in the USA has led to the inclusion of major surgery, such as mastectomy and vaginal hysterectomy, often with little regard for patient comfort and preference. This has resulted in a backlash, with legislation to prohibit the ‘drive-through’ mastectomy.

  The social circumstances

Day surgery needs ready access to a hospital or GP after discharge, although the demand on these should be minimal.

A responsible adult to escort the patient home and care for them at least until the following morning is mandatory. For more major day-case operations, longer care may be needed. Elderly or disabled partners may be unsuitable.

Patients must have reasonable home circumstances with good toilet facilities, few stairs to climb and access to a telephone.

Patients should live within 60 minutes’ travelling distance, both to reduce discomfort on the way home and to have ready access to hospital care if needed. Patients should not travel home by public transport.

Other options have been used where home circumstances are not ideal, such as hospital hotels supplying overnight supervision at low cost or, more rarely, transfer to a com­munity hospital. An overnight stay in hospital (the ‘23-hour admit’) may permit more procedures and patients to be considered suitable ‘day cases’, but may not achieve the benefits of day surgery.

 Developing countries with long distances and difficult travelling conditions to reach medical care may find that these are obstacles to introducing day surgery.

The fitness of the patient for general anaesthesia

The patient should be medically stable and have been screened before admission to exclude major health problems. The American Society of Anesthesiologists (ASA) classification of patient fitness is often used, with the stipulation that ASA 1, 2 and stable 3 patients are suitable, although this may be difficult to define with accuracy. The aspects of patient fitness which have been shown to relate to complications during surgery and to unplanned overnight admission are severe symptomatic respiratory disease, symptomatic cardiac disease and hypertension.  

Age. 70 is often taken as an upper age limit, but the physiological age of the patient is more important than actual age. Elderly patients may be suitable for day-case procedures under local or regional anaesthesia.

The lower age limit depends on the facilities available, the experience of the staff and the procedures undertaken. The   healthy full-term neonate is suitable for minor day-case pro­cedures, provided that there is immediate access to in-patient neonatal care if needed. More caution is needed with pre­term or expreterm babies, who should not be considered before 60 weeks’ conceptual age because of the risk of perioperative apnoea.

Obesity. Weight limits expressed as body mass index (BMI) (weight in kg/height in in2) are often imposed, although there is little hard evidence as to what is unacceptable. Surgery and anaesthesia are undoubtedly more difficult and have more complications in overweight patients, who may also have more health problems. Although a BMI of 30 is often taken as an upper limit, in otherwise fit patients problems do not really become apparent until the BMI exceeds 35.

Respiratory disease. Asthmatics with no history of hospital admission for their asthma, and patients with chronic obstructive airways disease, are suitable for day surgery if they have reasonable exercise tolerance, usually expressed as the ability to climb a flight of stairs.

Hypertension. Untreated or previously unrecognised hypertension in apparently fit patients is the commonest predictable reason for cancellation on the day of surgery, and ‘white coat hypertension’ on the patient’s arrival in hospital is a recurring source of strife between surgeons, anaesthetists and GPs. However, this type of hypertension has been shown to be related to abnormal left ventricular function and to perioperative myocardial ischaemia. A preadinission blood pressure (BP) is mandatory, and BP _ 175/105 mmHg should be treated before surgery, together with electrocardiography (ECG) and full cardiac history to exclude more severe underlying cardiac disease.

Cardiac disease. Unsuitable conditions include cardiac failure, symptomatic valvular disease, severe or rest angina, fast ventricular arrythmias, unpaced second or third degree heart block, or myocardial infarction within the previous 6 months. In patients with lesser degrees of heart disease, further cardiac assessment may be required.

Diabetes. 

Well controlled noninsulin-dependent diabetes (NIDDM) usually poses no problems. Although otherwise fit insulin-dependent diabetics have been considered suitable, in practice, even with a well-controlled and well-motivated patient, the stress of surgery and fasting can upset the patient’s diabetic control, making their day surgery episode difficult and time-consuming for medical staff.

Drug therapy. Patients taking anticoagulants, systemic steroids, digoxin, drugs for dysrrhythmias and angina, and monamine oxidase inhibitors need individual anaesthetic evaluation before booking for day surgery. Oestrogen containing oral contraceptives need not be discontinued except for lower limb operations, particularly where a tourniquet will be used.

This is only a guide. There are no absolute exclusions — the severity must be evaluated — and local or regional anaesthesia may be suitable for patients who cannot safely be given a general anaesthetic. Simple guidelines (Table 69.7) should be circulated to surgical staff and displayed in out-patient departments.

Assessment before admission for surgery

This is an essential component of well-organised day surgery. The timing should allow any problems to be sorted out, but not be so far in advance that the patient develops new problems.

Methods of assessing patients

Surgeons are not good at assessing patients for anaesthetic fitness, particularly in the middle of a busy clinic. The ideal would be to have the patient seen by an anaesthetist, preferably the one who will anaesthetise the patient. This is usually impracticable in terms of time, cost and available anaesthetic time. The best alternative is a filtering process (Fig. 69.1) with specially trained nurses using patient questionnaires (Table 69.8) and locally agreed protocols of suitable criteria. Borderline cases are referred for anaesthetic opinions, and consultant anaesthetists involved in day surgery should be identified to advise.

Assessment clinics

A good assessment clinic prevents cancellation on the day of surgery for predictable reasons, particularly hypertension. It also speeds up the process of admitting the patient, and may reduce unplanned overnight admission for those who have not arranged for an escort home. It can reduce unnecessary investigations, perioperative complications and risk. Patient compliance may be improved — given information and the opportunity to discuss anxieties, they are more likely to turn up for their operations and to have obeyed their preoperative instructions (Fig. 69.2). It should also increase the number of suitable patients by addressing problems, and by arranging for borderline cases to be considered for local or regional anaesthesia. Assessment clinics are cost-effective (Table 69.9).

Preadmission in formation

This has been identified as a cause for patient dissatisfaction. Providing clear concise information means that patients arrive well prepared, having obeyed the fasting instructions, and knowing what to expect from the surgery and in the recovery period. The prolonged fluid fast of former times may be detrimental to recovery, and although a 4—6-hour fast from solid food is essential, clear fluids my be allowed up to 2—3 hours preoperatively. Information about expected levels of pain and restrictions on activity after specific procedures helps the patient to plan their care at home — for instance mothers of small children may need to arrange for help for longer than just overnight. All of the important information (Table 69.10) should be on one page, or patients may not read it. Separate leaflets on individual procedures are useful. Resist the temptation to overload the patient with information.

Anaesthesia for day surgery

Anaesthetic morbidity is a major reason for unplanned admission, in particular sleepiness, dizziness and nausea (Fig. 69.3). The choice is between local or regional anaesthesia with or without mild sedation, or general anaesthesia with local anaesthetic where appropriate to provide postoperative analgesia.

Local or regional anaesthesia is perhaps the ideal, although it is not suitable for all procedures or patients. It is excellent for elderly patients and is usually economical, although it may be more time consuming than general anaesthesia, and necessitates gentle surgery. Patients and surgeons may express a preference for general anaesthesia.

The type of local anaesthesia must be carefully chosen. Central anaesthetic blocks, epidural, spinal or caudal, may be less suitable because of the time taken to carry out the block and allow it to work, the time taken for the patient to mobilise and the high incidence of urinary retention.

Suitable blocks are listed in Table 69.11. The ideal choice of agent is a long-acting one, such as bupivacaine, and if speed of onset is important lignocaine may be mixed with this. Prilocaine will be needed for Bier’s blocks (intravenous regional anaesthesia). Care should be taken not to exceed safe doses, and if the surgeon administers the local anaesthetic, an anaesthetist should be available for anything more than very minor procedures, in case of complications.

General anaesthesia

Propofol, a newer anaesthetic agent, has established itself as the agent of choice for the induction, and often also the maintenance, of day-case patients because of its good anaesthetic conditions, rapid problem-free recovery and lack of postoperative nausea and vomiting (PONV). Indeed, it is antiemetic, a major advantage in day surgery. Children are increasingly induced intravenously. For inhalation induction sevoflurane has now replaced halothane in many countries because of its ease of use and speed of recovery.  

Maintenance of anaesthesia is commonly with a volatile agent, such as isoflurane or enflurane, and nitrous oxide in oxygen. The newer volatile agents, desflurane and sevoflu­rane, with ultrafast immediate recovery times, have proved disappointing, as like all volatile anaesthetic agents they have a high incidence of PONV which delays recovery, and little advantage has been shown to justify their increased cost. Many day surgery anaesthetists therefore use propofol by infusion to maintain anaesthesia, as well as for induction —total intravenous anaesthesia (TIVA). The increased cost may be justified in view of the excellent recovery, particularly after longer procedures and where the risk of PONV is high.

Short-acting opioids, such as alfentanil or fentanyl, are usually included in the general anaesthetic to reduce the dosage of other drugs and to provide some analgesia in the early postoperative period.

The laryngeal mask airway (LMA) has become popular in day surgery as it allows fast easy control of the airway, and endotracheal intubation and its hazards often can be avoided. It is now commonly used for straightforward laparoscopies, and for dental and head and neck procedures.

Sedation

This is given ideally by an anaesthetist, but sometimes by other medically qualified personnel. The sedationist must not be involved in the procedure: the single-handed operator— sedationist is neither safe nor medicolegally defensible. Monitoring is required and supplemental oxygen is usually given. Sedation means that the patient is relaxed and calm while maintaining rational verbal contact. It is all too easy to oversedate the patient beyond this level, so that the patient is anaesthetised and airway control may be lost. Sedation is best left to experienced anaesthetists.

The use of midazolam, a short-acting benzodiazepine, is popular but its long-lasting postoperative amnesia may mean that postoperative instructions are forgotten. Propofol in low dose is very suitable for sedation, with faster wake-up and less amnesia, although some patients may prefer not to recall events in theatre. Small doses of opioids may also be used with caution, but may result in respiratory depression or apnoea.

Analgesia

Good pain control is essential. It is a major reason for delay in discharge (Fig. 69.3), unplanned overnight admission, GP consultations after discharge, and, not least, patient distress and dissatisfaction. It limits early patient mobilisation and prolongs return to normal function. The use of morphine, while successful in controlling pain, is less successful in day surgery because of its sedation and high incidence of nausea, which may only become apparent after the patient leaves the DSU. In order to avoid its use, a mixture .of analgesic methods is needed — so-called balanced or multimodal analgesia. Nonsteroidal anti-inflammatory drugs (NSAIDs) plus local anaesthesia, where possible, form the basis, with additional short-acting opioids and other mild analgesics if needed. Although none of these methods is sufficient alone, in combination they are very effective.

The best local anaesthesia will not last longer than the evening of surgery, so it is important to provide sufficient oral analgesia for 3—5 days postdischarge. These should be prepared in packs supplied to the DSU and prescribed according to the expected pain for that operation (Table 69.12). Combinations of regular NSAIDs with simpler analgesics for break-through pain are successful. Unless clear instruction on their use is given, patients’ compliance may be poor (Table 69.13).

Discharge

The patient must be seen before discharge by the surgeon and the anaesthetist, or their deputies. Formal discharge criteria are required, with documentation signed by the individual delegated to discharge the patient, usually a nurse. The patient and their escort must be given clear instructions on what to do after their general anaesthetic and surgery, includ­ing stitch removal and follow-up where needed (Tables 69.14 and 69.15).

Follow-up, audit and quality control

Good day surgery practice means that the incidence of non-attendance, cancellations, complications before and after discharge, overnight admission and readmission is audited, and improvements are made where needed. Where possible, a telephone call to the patient the next day reassures the patient and gives immediate feedback on the adequacy of analgesia and other problems. Specific audits should be conducted on patient satisfaction with their overall management, morbidity related to specific types of surgery and anaesthesia, and the adequacy of postoperative analgesia. The involvement of community services and GPs should be monitored.