Some thoughts on anaesthesia!
Patient selection - a surprisingly large majority of patients do well with laparoscopic surgery. Permitting hypercarbia, in the absence of cardiac arrhythmias, allows most patients to be ventilated with acceptable airway pressures. We have not yet had a patient have left ventricular failure during this type of surgery; where there have been concerns about this, Mr Dixon has usually been able to operate with a lightly reduced pressure in the abdomen.
Good operating conditions speed the surgery and are better for the patient. Full muscle relaxation is essential, because any contractions in the musculature of the abdominal wall can produce wild movements of both the laparoscope and the operator’s instruments.
We use patient positioning to harness the effects of gravity to place the viscera in a good position to allow a clearer view of the operating site. We have never found the need to use underbody "gel mats ", shoulder restrains etc. Provided that the "slippy slidy" transfer mat has been removed and there is no plastic cover on the canvas patients do not slide!
Shoulder restraints can lead to a brachial plexus neuropraxia or worse. All the major units have had a case and yet they still advocate them. All good news for my medicolegal practice!
Patients need to be observed during surgery, to ensure that they have not shifted on the table. A bairhugger “Torso” blanket with the clear face piece makes this observation easier.
Intubation is the best way to manage the airway, because it allows ventilation to be fully controlled despite the pneumoperitoneum and (sometimes) extreme patient positioning. I normally use pancuronium for the fit patient having surgery lasting an hour or more, but for all other cases—especially the elderly—I find atracurium is more reliable in terms of reversibility. (Vecuronium is a particular nuisance in some of these very elderly patients.) Fentanyl works well for the majority of these patients but, for the frail elderly patient alfentanil by bolus and/or infusion may be a better way of providing low levels of cardiovascular stress, coupled with a good return to spontaneous breathing at the end of surgery. Unlike remifentanil, alfentanil provides some useful postoperative analgesia. How much fentanyl? On average I use 5 to 7 mcg/kg at induction for surgery lasting 40 minutes or more. They do breathe afterwards!
Induction, with propofol, whilst the patient holds the pre-oxygenation mask on themselves. After this generous dose of fentanyl, most patients lose consciousness at around 1 mg/kg. Maintenance is usually with isoflurane or desflurane with air and oxygen. I avoid nitrous oxide wondering whether it would diffuse into gas pockets left at the end of surgery and make the postoperative discomfort worse.
Blood pressure control is important, if after load is to be low enough to avoid putting the left ventricle under strain. In the elderly and other less-fit patients, I use desflurane at an end-tidal concentration of 4 to 10% as a vasodilator, knowing that it will dissipate rapidly and allow a clean wake-up at the end of surgery. Isoflurane can be used similarly (1 to 2.5%) in fitter, younger patients. Fluid/blood replacement during surgery. Beware! It is easy to swamp these patients - they need very little fluid.
As a specialist in pain, Epidural anaesthesia seems inappropriate and unnecessary. It also exposes the patient to potentially very serious morbidity. Intravenous paracetamol and diclofenac coupled with liberal use of bupivicane infiltration provides very good pain relief. We occasionally need a 10mg dose of oral morphine during the first 24 hours. In recent months we have moved over to use TAP blocks to provide peri and postoperative analgesia. It is so simple. The results are spectacular! I ask myself, why was TAP not thought out years ago?
A cup of tea and a digestive biscuit are welcomed post operative fluid and nutrition. Sort this out yourselves as the recovery nurses will think that you are mad! They will soon learn. Let the patient eat and drink as they wish and get them up and about.
Provided that the surgery has been straightforward and swift, remove the patient’s catheter at the end of the procedure. For starightforward resections we now advocate no catheter, only an in-out at the end of the procedure. Hold your nerve they usually PU.
If the patient is not sitting up eating their breakfast the next morning IT IS A GOOD MAXIM TO ASSUME that something has gone wrong and consider re-laparoscoping them.
Over 34% of our resectional patients where TAP has been employed are discharged within 24hrs of completing their surgery! Some resectional patients feel a little low and bloated on day two. This quickly passes to allow discharge on day three. It is unusual for non resectional colorectal patients to stay beyond 24hrs.