1. Anaesthetic management of the surgical patient

2. Outline Introduction History and Physical Examination
Special Investigations
Risk Assessment
Preoperative therapy
Premedication
Intraoperative management
Post-operative management

3. Introduction
Pre-operative visit is essential to assess “fitness for anaesthesia”
Aims of the visit:
-Establish a rapport
Obtain a history and perform a physical examination
Assess the risks of anaesthesia and surgery
Institute preoperative management
Prescribe premedication and plan the anaesthetic management
Establishment of rapport

4. History and physical Examination- History
History- ask direct questions about allergy, infections, blood transfusion, previous anaesthetics, diseases of the CVS and RS
Smoking
Alcohol
Drug history- administration of most drugs should be continued up to and including the morning of operation and some should be discontinued

5. Physical Examination
A full PE should be undertaken and documented in the case records
Assessment of ease of tracheal intubation- examine teeth for presence of caries, caps, loose teeth and protruding upper incisors, mouth opening, cervical spine flexion

6. Special Investigations
Before ordering extensive investigations, the anaesthetist should ask himself:
-will the investigations yield information not revealed by physical investigations?
Will the results of the investigationalter the management of patients?
Guidelines: Urine analysis, HB, Eand U, Cr,LFT, CXR, ECG,Sickle status, ABG, Sickle status

7. Risk assessment
ASA=American Society of Anaesthesiologists Physical status scale
Mortality rates after anaesthesia and surgery each ASA physical status(%)
ASA 1 = Healthy patient (0.1)
11= Mild systemic disease (0.2)
111=moderate systemic disease (1.8)
IV =Severe systemic disease ( 7.8) V= Moribund patient (9.4)

8. Prediction of risk factors in general
Important factors in predicting post-op morbidity and mortality in decreasing order:
Clinical assessment- ASA>3
Cardiac failure
Cardiac risk index
Pulmonary disease
Pulmonary abnormalities confirmed by X-ray
ECG abnormalities

9. Common causes of postponing surgery
Acute upper respiratory tract infection
Existing medical disease which is not under optimum control
Emergency surgeru for which the patient has not been resuscitated adequately
Recent ingestion of food- the rule
Failure to obtain informed consent
Drug therapy

10. Preoperative therapy Respiratory disease- optimise
Cardiovascular disease-e.g. hypertension
Obstructive jaundice- start iv infusion the night before surgery
Blood transfusion requests- depends both on
the nature of the surgery and patient features

11. Premedication
=administration of drugs in the period 1-2h before induction of anaesthesia, The objectives are:
1. Allay anxiety and fear (Psychotherapy)
Reduce secretion
Enhance the hypnotic effect of general anaesthetic agents
Reduce post op nausea and vomiting
Produce amnesia
Reduce the volume and increase the pH of gastric contents
Attenuate vagal reflexes
Attenuate sympathoadrenal responses

12. Drugs used for premedication
Benzodiazepines eg diazepam, lorazepam
Opioid analgesics
Butyrophenones e.g haloperidol, droperidol
Phenothiazines
Anticholinergics e.g atropine, hyoscine and glycopyrronium

13. induction
Objective of modern anaesthesia is to rapidly obtain a state of unconsciousness, to maintain this state and then achieve a rapid recovery.
Modern anaesthesia thus involves the use of several drugs to provide hypnosis, analgesia and muscular relaxation
Methods available for induction
-Intravenous
- Inhalational
- Intramuscular: ketamine only

14. Tracheal intubation Indications – 2 major ones:
1. to ensure airway patency
2. to protect the airway from aspiration
Airway patency important in:
Prolonged operations
Operations where access to the airway is difficult
Operations involving excessive movement of the head and neck
Use of LMA or face mask is unsuitable
Where a major intraoperative complication develops

15. Protection from aspiration
Use a cuffed endotracheal tube to prevent aspiration eg for:
Potential for vomitting and aspiration
Situations of extensive bleeding from the mouth, nose or oropharynx
Thoracic operations

16. Inhalational anaesthetic agents
Inhalational agents
Anaesthetic gases
Di-ethyl ether
Halothane
Isoflurane
Enflurane
Sevoflurane
Desflurane
Nitrous oxide
Oxygen

17. Intravenous agents Muscle relaxants Sodium thiopentone Propofol
Ketamine
Suxamethonium
Pancuronium
Atracurium
Vecuronium
Antagonists
Neostigmine
Pyridostigmine

18. Complications following the use of Muscle relaxants
Inadequate ventilation
Residual paralysis
Prolonged apnea

19. Care of the unconscious patient
Emergence can be associated with major morbidity, especially from respiratory and cardiovascular complications.
The patient may develop airway obstruction or inadequate ventilation with subsequent hypoxaemia and hypercapnia and is at increased risk of aspiration due to the absence of protective airway reflexes.
Effects of ongoing blood losses and residual drug effects
Observation and early intervention during this period is crucial

20. Criteria to be met before transfer from recovery room to general ward
Level of consciousness
-obeys command
-Spontaneous eye opening
Respiratory system
-upper airway
-respiration
Pain control
-adequate pain control
-adequate analgesic and anti-emetic provisions
Cardiovascular system
-haemodynamically stable
-pulse rate acceptble
-blood pressure acceptable
-No persistent bleeding
-Peripheral perfusion adequate
Temperature
No hypothermia or malignant hyperthermia

21. Comparison of methods of induction
INTRAVENOUS
Advantages
Rapid onset
Dose titratable
Depression of pharyngeal reflexes
Anti-emetic /anticonvulsant
Disadvantages
Venous access required
Risk of hypotension
Apnoea common
Loss of airway control
anaphylaxis
INHALATIONAL
Advantages
Avoids venepuncture
Respiration is maintained
Slow loss of protective reflexes
End tidal concn can be measured
Upper oesophageal tone maintained
Disadvantages
Slow process
Potential excitement phase
Irritant and unpleasnt
Pollution
May cause a rise in ICP/IOP