Adult Anesthesia for Eye Surgical Procedures

Surgery is performed under anaesthesia. The purpose of anaesthesia is to ensure the necessary comfort of both the patient and the surgeon during an operation. Your ophthalmologist is the one who selects the most appropriate anaesthetic technique for the type of surgical procedure you are going to undergo but the anaesthetist may change this option if he/she deems it to your benefit and safety, the anaesthetic technique being presented to you later.

The proper conduct of an operation also requires good quality anaesthesia, which means:

• control of pain caused by surgical incisions during the operation;
• sedation or deep sleep to control the stress induced by the intervention;
• deep relaxation of the muscles in the operated area to ensure to the surgeon all the comfort necessary to perform the operation in the best conditions;
• all this must be done in conditions of stability of the vital functions of the body (for example: oxygenation, blood pressure, heart rate, fight against dehydration, prevention of infection);
• all the aspects listed above are the responsibility of the anaesthetist.

The choice of the type of anaesthesia depends on:

• the operation you will undergo;
• your answers to the questions that will be addressed to you;
• your state of health;

---

Types of anaesthesia used in ophthalmological surgery

• Local anaesthesia: it is done by injection or by applications (drops or ointments) of anaesthetic – topical anaesthesia that numbs the eye. You will remain conscious during the intervention and certain manoeuvres may be perceived as unpleasant. Topical anaesthesia may be an option for short-term interventions, but in most situations, especially in interventions for strabismus, local injection of anaesthetic may also be necessary. Certain interventions in the orbital area can be performed comfortably under local anaesthesia – for example eyelid surgery.

Local anaesthesia can trigger allergic reactions to the anaesthetic substance, so patients with a history of reactions to local anaesthetics should avoid this type of anaesthesia.

• General anaesthesia: provides a controlled state of loss of consciousness. You will fall asleep deeply and quickly from the moment the hypnotic substance is injected and you will not feel anything. Analgesic substances to control pain, muscle relaxants are used, and respiratory function is partially taken over by the artificial respiration system of the anaesthesia machine, with the help of a probe placed in the trachea by the anaesthesiologist (orotracheal intubation). The anaesthetics are either injected into a vein, or inhaled, or are administered in combination and at the end of the intervention the effects quickly disappear and the state of consciousness is regained. A local anaesthesia can be converted to a general anaesthesia if necessary.
• Intravenous sedation: sometimes for short-term interventions short-term anaesthesia or intravenous sedation is performed. You will fall asleep when the hypnotic substance is injected and you will not feel anything; you will breathe alone or with the help of your anaesthesiologist using an oxygen mask. Sedation can be successfully associated with local anaesthesia, especially when a short period is required in which the patient must interact with the surgeon for optimal surgical outcome.

All these anaesthetic techniques are practiced in the OFTAPRO clinic.

---

Anaesthesia for adjustable sutures

There are situations in which compliant and balanced patients can benefit from a surgery with adjustable sutures under topical /local anaesthesia associated with a mild sedation, thus optimizing the final result of the surgery. The best indication for this purpose is for patients with small squint deviations, those who are very old or who have a contraindication for general anaesthesia, those with diplopia (double vision) or those who are getting an operation for cosmetic purposes to correct eyelid ptosis (drooping eyelid). The result of the surgery can be checked during the operation allowing an intraoperative adjustment of the eye position or up to 24 hours postoperatively. In OFTAPRO clinic, these interventions have been performed since 2000.

Most interventions on the extraocular muscles, at the level of the orbit or at the level of the tear ducts, however, require general anaesthesia.

---

General anaesthesia

It involves the loss of consciousness and the sensation of pain, being a state of deep sleep. The anaesthetic can be administered intravenously (intravenous anaesthesia) or by means of an inhaler (a mask covering the mouth and nose). The mixture of anaesthetic gas and oxygen can be administered in a tube that is placed in the larynx (laryngeal mask) or in the trachea (orotracheal intubation), after the patient is deeply asleep. Intubation facilitates airway control and reduces the risk of aspiration of saliva or gastric contents into the lungs; it also allows the administration of muscle-relaxing medication, which leads to improved surgical conditions.

In addition to substances administered by inhalation, other complex substances that facilitate anaesthesia and control its stages are administered intravenously during general anaesthesia.

During general anaesthesia you will not feel anything and even after waking up the comfort will be good because the painkillers will still act upon the body.

---

Preanaesthetic preparation

How to prepare for anaesthesia for surgery before you go to the clinic:

• For smokers – we recommend you to stop smoking a few weeks before, the sooner, the more the risk of lung complications decreases. If you can’t stop smoking, even reducing the number of the cigarettes smoked helps;
• If you are overweight weight loss by means of a diet helps reduce the risk of anaesthesia, if possible;
• About 2 days before the operation we recommend to patients who do not have a contraindication, to drink more fluids than usual;
• If your teeth or prosthetic works are moving or if you have dental infections, we recommend that you go to the dentist first, to avoid the risks of their detachment, or the risk of infection spread for situations in which the anaesthetist will have to intubate you.
• If you have a chronic medical problem, such as: diabetes, asthma, thyroid problems, epilepsy, hypertension, heart disease, you should check with your doctor and bring medical documents specifying the diagnosis and treatment of these diseases.
• The anaesthetist must be informed of the chronic medication you are currently taking, especially medication that may interfere with the anaesthetic;
• Please be sure to mention if you are taking nutritional supplements or natural remedies – many of these can interfere with anaesthetics!

The anaesthesiologist may detect a problem in your health that would increase the risk of surgery and anaesthetic risk and therefore may consider postponing surgery to re-evaluate and treat this problem.

---

Possible postoperative effects

The following postoperative effects may occur: severe nausea or vomiting, hoarseness or difficulty in swallowing after intubation, headache.

Side effects and risks of anaesthetic procedures

These are associated with complex procedures, complications that may occur during surgery or investigation-treatment procedures performed under anaesthesia/ sedation occurring even in conditions of maximum care, exigency, professionalism, high level equipment, with a large number of possible causes related both to the limits of medical sciences and to the basic or associated pathology, possibly other than that covered by the medical procedure requiring anaesthesia / sedation, known or unpredictable side effects of the drugs used, the manoeuvres and the equipment / instruments implicitly associated with the technique used.

The most common complications of anaesthesia are as follows:

Hematomas (localized collections of blood), significant bleeding and infections at injection sites Abscesses formed after injection, tissue necrosis are rare (one case per thousand anaesthesia procedures); only in exceptional cases they require surgical resolution.

Temporary or permanent nerve damage (with sensitivity to touch or altered sensitivity) is rare; persistent paralysis due to nerve injury is exceptionally rare.

Side effects of anaesthetics and other medicines used (e.g. infusions) may occur in particular in certain patients with hypersensitivity and/or certain pre-existing diseases, which must be specified in the medical history questionnaire.

Severe allergic reactions and other potentially fatal complications – they are extremely rare in all anaesthetic procedures. Any type of anaesthesia, especially general anaesthesia, presents a risk of postoperative complications (e.g. thrombosis, renal failure, liver failure, cardiac arrest – with a frequency of 0.8/10,000 eye surgeries) which can result in the death of the patient, regardless of the preventive measures taken, the technique and equipment used, the experience of the medical team, the accuracy of the techniques practiced, this statistic including all age categories and all types of eye anaesthesia.

Nausea and vomiting are rare, life-threatening situations due to the ingress of vomit fluid into the airways being very rare.

Intubation can result in temporary swallowing difficulty and hoarseness. Rarely, lesions of the throat, larynx or trachea or lesions of the vocal cords may occur, associated with permanent damage to the voice (hoarseness) and breathing difficulty. Tooth damage can also occur, even the loss of teeth, especially in the case of periodontitis or baby teeth.

Up to date, more than 12,000 interventions under general anaesthesia have taken place in OFTAPRO. With the help of the team of professionals that we have, so far no side effects or major complications of anaesthesia have been reported, regardless of its type.