Complications of anesthesia This topic aim to provide information on some common clinical condition that occur to the patients after anesthetized required procedure

1. COMPLICATIONS OF
ANAESTHESIA
Presenters-Mohamed Kitiku Ghaba
Kileng'a Grayson
Supervisor: Dr Renatus

2. OBJECTIVES
AT THE END OF THE PRESENTATION, EVERYONE SHOULD HAVE INSIGHT
ON:
• What is complications of Anesthesia?
• What causes the Anesthetic complications?
• Where and when does the Anesthetic Complications occurs?
• How does the Anesthetic Complications affect different body
systems?
• How to manage Anesthetic Complications?
• How to minimize the severity of Anesthetic Complications?

4. What are the complications of Anesthesia?
• Anesthetic Complications are the unfavorable and unintended results
following the administration of anesthetics on patients.
• In Anesthesia the development of complications depends on number
of factors, including the degree of vulnerability, susceptibility, age,
health status and immune system condition.
• Knowledge of the most common and severe complications of
anesthesia allow for recognition, prevention and preparation for
treatment if they should occur.

5. What causes Anesthetic Complications?
• Causes of Anesthetic Complications are multifactorial, hence not
limited only to Anesthetic Medications.
• Despite the fact that Anesthetic Medications are not genuinely safe,
complications are outcome of interactions of the anesthetics with
other factors
• The factors can Anesthesiologist related, Patient related,
infrastructure related and Surgical related

6. Anesthetics related causes
• Drugs : Pre-operative medication e.g. hypotensive agents, recent
steroid therapy, Induction agents ;Inhalational agents or IV agents,
Muscle relaxants (overdose or hypersensitivity reaction)
• Inadequate expertise
• Insufficient depth of anesthesia

7. Surgical related causes
• Position, e.g. reverse Trendelenburg or lateral position
• Blood loss with inadequate fluid replacement
• Vagal stimulation- reflex bradycardia
• Surgical Manipulations and Techniques
• Embolism, e.g. air or amniotic fluid
• Emergency VS Elective surgery

8. Patient related causes
• General medical state of the patient : Hypervolemia i.e. blood loss or
dehydration, Heart disease (ischemic) and heart failure. Arrhythmias:
tachycardia and bradycardia. Chronic Obstructive Pulmonary diseases
• Age of the patient (advanced age, pediatrics)
• Anatomical variations among people.
• Genomics and genetics
• Lifestyle: alcohol use, cigarette smoking, obesity,

9. Where and when does Anesthetic
Complications occurs?
• Anesthetic Complications occurs “ANYWHERE AND ANYTIME”
• Following the administration of anesthetic medications, the room for
complications is not limited to place and time.
• They can either occur in the preoperative, intraoperative or post
operative settings.
• The prevalence of Anesthetic Complication in low Income and Middle
Income countries in very high.

10. Classification of Anesthetic complication in
body systems.
• Cardiovascular complications
• Respiratory complications
• Gastrointestinal complications
• Urinary complications
• Neurological complications
• Complications in eye surgery
• Other complications − Shivering − Awareness during anesthesia −
Malignant hyperpyrexia

11. 1 Respiratory Anesthetics complications
• Airway obstruction
• Apnea and Hypoxia
• Aspiration pneumonitis
• Pulmonary edema
• Transfusion-related acute lung injury
• Increased left to right shunt
• Atelectasis
• Pneumothorax

12. Airway Obstruction in Anesthesia
Possible Causes of upper airway obstruction
• Loss of pharyngeal muscle tone: some pharyngeal muscles are important
in maintaining the patency of the airway. the genioglossus is the primary
muscle that keeps the tongue away from posterior pharyngeal wall via
tonic and reflex respiratory activity together tonic activity of the levator
palantini, tensor palantini, palatopharyngeus and palatoglossus which
elevates the soft palates. This is out come of Sedation, obstructive sleep
apnea, Residual Neuromuscular blockade.
• Laryngospasm: by airway irritants such as thiopental,isoflurane with
anesthetic and patients related factors

13. Management of upper airway obstruction
• Perianesthetic decisions, evaluations and monitoring.
• Call for help.
• Clear the airway of secretions
• Perform airway opening maneuvers i.e Jaw thrust with CPAP (5 to 15 cm
H2O) with 100% Oxygen.
• If CPAP is not effective, an oral, nasal, or laryngeal mask airway can be
inserted rapidly.
• Hydrocoritsone 100 mg IV- to relieve inflammation and edema
• If no improvement rapid intubation to secure the Airway(ET intubation)

14. Management of Upper airway obstruction
• After successfully opening the upper airway and ensuring adequate
ventilation.
• Cause of the upper airway obstruction should be identified and treated.
• In adults the sedating effects of opioids and benzodiazepines can be
reversed with persistent stimulation or small titrated doses of naloxone
(0.3 to 0.5 µg/kg IV) or flumazenil (0.2 mg IV to maximum dose of 1 mg),
respectively.
• Residual effects of neuromuscular blocking drugs can be reversed
pharmacologically or by correcting contributing factors such as
hypothermia

15. Apnea and Hypoxia
• Hypoventilation and apnea generally result in Hypoxia and Carbon
dioxide retention. However, it is important to remember that if the
inspired oxygen concentration is very high, then CO2 retention may
occur unaccompanied by hypoxia. This may occur during the
operation and postoperatively in the recovery room.
• Causes :-Hypoventilation due to – muscle weakness, pain, respiratory
depressant drugs
• Airway Obstruction – by the tongue, Laryngospasm, Bronchospasm or
kink or Fb in ETT

16. Causes of Apnea and Hypoxia
• Complications of laryngoscopy and intubation
1. Errors of ETT positioning i.e. esophageal intubation, endobronchial
intubation
• 2 Airway trauma tooth damage, sore throat, pressure injury on
trachea, edema of trachea or glottis
• 3 physiological response to airway instrumentation i.e.laryngospasm
bronchospasm

17. Aspiration Pneumonia
Aspiration Pneumonitis ( Mendelson Syndrome )
Stems from aspiration of gastric content of pH less than 2.5
Signs
• dyspnea
• tachycardia
• tachypnea
• cardiovascular collapse i.e. hypotension
• auscultation of chest reveal wheeze and crepitation

18. Prevention of Aspiration Pneumonia
• fasting several hour before procedure.
• use of regional anesthesia if possible if no contraindication.
• attempt to empty stomach with wide bore nasogastric tube.
• Rapid sequence induction.
• Drugs like cimetidine and ranitidine ( H2 receptor blockers ).

19. Management of Aspiration Pneumonia
• Repeated tracheal suction, preceded by 100% oxygen administration
or Oxygen therapy by mask
• Bronchodilators:
− Ventolin is the mainstay of treatment given via nebulas, IV
(250micrograms over one minute) or IM (500micrograms four
hourly for adults).
− Aminophylline 250 mg stat IV over 10 mins followed by an
infusion if necessary.

20. • IPPV with oxygen - if severe i.e. refractory hypoxia.
• Bronchoscopy

21. Gastrointestinal Anesthetics Complications
• Nausea and Vomiting : due to the increase in the intra-gastric
pressure, that is either drug induced or patient related.
• Drug induced includes
• Patient related includes patients at high risk such as: Those with
obstructions in any part of the gastrointestinal tract, incompetent
lower esophageal sphincter, who have a delay in the gastric emptying
time(Pregnant women, serious ill patients and head injuries) and
with raised intra-abdominal pressure.

22. Nausea, Vomiting and Regurgitation.
• Vomiting is an active process involving expulsion of the material from the
alimentary tract by muscular contraction.
• Regurgitation is passive process that does not involve any muscle action. It
occurs silently and is more dangerous than vomiting.
• Vomiting and aspiration of gastric contents can occur during the induction
and maintenance phases of the anesthetic or during recovery.
• Adversities includes Hypoxia due to large volumes of liquid can flood the
lungs, laryngeal spasm and Aspiration pneumonitis if the gastric contents
are very acid (pH< 2.5). Cardiac arrhythmias secondary to hypoxia.
Respiratory infections, e.g. bronchopneumonia, atelectasis.

23. Management of Vomiting and Regurgitation.
• Patients at risk of vomiting or regurgitating under anesthesia should
always be anaesthetized using the technique of rapid sequence
induction with cricoid pressure.
• IV fluids
• Medications (Ondansetron/ metoclopramide/ Promethazine)
• Positioning

24. Cardiovascular Anesthetic complications
A Hypotension
Causes :
• Drugs induced: premedication(opioid),induction agents (thiopental),
inhalational agents (halothane),Muscle relaxant overdose eg
pancuronium and atacurium
• Over inflation of the lungs ( excessive positive pressure )
• Blood loss without adequate fluid replacement
• Vagal stimulation – reflex bradycardia

25. Hypotension cont.
• Marked hypotension carries a risk of Cerebral , Myocardial and Renal damage
following ischemia or thrombus formation
MANAGEMENT OF HYPOTENSION
• Call for help
• Start rapid infusion of iv fluids ( Hartman's saline or colloids )
• Increase concentration of oxygen and reduce the concentration of anesthetic
agent
• vasopressors are useful if only hypotension is due peripheral vasodilation e.g.
in spinal or certain anesthetic agent but not in hemorrhage or dehydration
where vasoconstriction is already present

26. Hypertension
• Cause – inadequate anarthria – intra operative pain
- both hypoxia and hypercarbia due to CO2retention
- Ketamine or pancuromium
- over transfusion
- malignant hyperthermia
- posture trendelburg posture
- infiltration of adrenaline
- increased ICP

27. Hypertension Cont.
• Dangers of persistent Hypertension during anesthesia includes cardiac
failure, stroke, Myocardial hypoxia and Cardiac arrhythmia
Management of Hypertension
• Call for help
• Correct the cause e.g. deepen anesthesia to relieve pain or increase
ventilation
• Correct the posture i.e. Elevate the head of the table
• Use hypotensive drugs if above measurement do not work e.g.
Hydralazine ( 5 mg iv ) or Propranolol

28. Arrhythmias
BRADYCARDIA TACHCARDIA
-drugs- suxamethonium - drugs- Atropine
neostigmine Pancuronium
halothane
- Reflex bradycardia -hypercarbia of any cause
- Late stage of hypoxia - early stage of hypoxia
- High spinal - hypotension
- Premedication with - inadequate depth of anaesthesia beta-
blockers or digoxin - thyrotoxicosis

29. 4 Urinary Anesthetic Complication
• Difficulty in passing urine
• This is more common after a spinal anesthetic but may also occur
after a general anesthetic.
• more common in anxious patients,
• those who have had abdominal, pelvic or perineal surgery,
• those who have had heavy sedation and in those patients with
enlarged prostates.

30. • Reduction in output (oliguria or anuria)
The normal urine output is about 1 ml/kg/hr., i.e. about 60 ml/hr. in the
adult patient. The minimum acceptable urine output is 0.5ml/kg/hr.
Cause :- Pre- renal cause Usually associated with volume depletion
(dehydration
or blood loss).

31. 5 Neurological Complications
• Awareness
Incidence : 0.2% increased in obstetrics, cardiac anesthesia and
hypovolemia. This occurs when ether, halothane or other volatile is not
used.
• Coma and convulsions
Convulsions and coma may also occur during or after general
anesthesia, perhaps after a period of acute hypoxia (e.g. associated
with a cardiac arrest)
or a period of chronic hypoxia (e.g. associated
with a partially obstructed airway or hypoventilation, etc.)
Delayed recovery due to cerebralhypoperfusion
cerebral depression drugs

32. 6 Others
• Shivering
-This is seen after general anaesthesia with halothane,
enflurane, ether and even thiopentone. It may be the body's
response to heat loss following vasodilation
-dry gases are breathed in through an endotracheal tube.
- Prolonged surgery and cold IV fluids also contribute to
hypothermia.

33. • Malignant hyperpyrexia
It is a fulminant skeletal muscle hypermetabolism syndrome occurring in
genetically susceptible patients to an anesthetic triggering agent
• This condition is rare but very dangerous.
• more common in patients with
muscular dystrophies and related disorders.
• Autosomal Dominant transmission
Triggering agent - halothane, enflurane, isoflurane
- suxamethonium

34. • Clinical signs under anesthesia
Spasm of the masseter muscle of the jaw and a general increase in
muscle tone in spite of neuro-muscular blockade.
Unexplained tachycardia
Hypercapnia in ventilated patients
Tachypnea in spontaneously breathing patients
Cyanosis
Arrhythmias
Rise in temperature
Later signs ( 6 – 24 hrs.) include skeletal muscle swelling renal and cardiac failure , DIC

35. • Management of malignant hyperpyrexia:
• Stop the anesthetic and surgery.
• Give 100% oxygen via endotracheal tube. Hyperventilate the patient.
• Dantrolene if available: initial dose 2.5mg/kg. Then 1mg/kg (up to
10mg/kg) repeated every 10-15 minutes
• Treatment of any arrhythmias as they occur.
• Cool the patient: Insert core temperature probe e.g. nasal,
oesophageal.

36. • Pack patient in ice or immerse in a cooling bath.
• Give IV infusion of cold fluids (cooled saline solution, 1000ml/10
minutes for 30 minutes).
• Gastric, wound and rectal lavage with cold saline solutions.
• Cooling fans.
• Stop cooling when central temperature falls to 38
• Monitor ECG, temperature, pulse and blood pressure.
• Maintain urine output with fluids, furosemide and mannitol.
• Keep patient sedated throughout with IV midazolam or diazepam.

37. Neurological Complication of Spinal And
epidural Anesthesia
• A) Anterior spinal artery syndrome ( Beck’s syndrome )
Ischemia or infarction of the spinal cord in the distribution of the
anterior spinal artery, which supplies the ventral two-thirds of the
spinal cord and Medulla.
Due to use of local anesthetics which contain epinephrine

38. • Presentation
Clinical features include quadriparesis (depending on the level of the
injury) and impaired pain and temperature sensation
BUT
Proprioception and vibratory sensation is preserved, as it is in the
dorsal side of the spinal cord.

39. Cont…
• B) Cauda Equina Syndrome
Cauda equina syndrome may result from any lesion that compresses CE
nerve roots. These nerve roots are particularly susceptible to injury,
since they have a poorly developed epineurium.
Usually intrathecal injection of LA during intended epidural anesthesia
and repeated intrathecal injection resulting in high concentration of LA
in restricted area and cause Neurotoxic injury

40. • Presentation
Signs include weakness of the muscles of the lower extremities
innervated by the compressed lumbar roots (often paraplegia),
detrusor weaknesses causing urinary retention and post-void residual
incontinence
decreased anal tone and consequent fecal incontinence
bilateral leg pain and weakness;
bilateral absence of ankle reflexes

41. References
• Clinical Anesthesiology by Morgan and Mikhail, 6th Edition.
• Management of Airway obstruction by J.Lynch and S.M.Crawley, BJA
EDUCATION, OXFORD ACADEMIC.
•

42. IS THERE ANY
QUESTION OR COMMENT?
THANK YOU!