2. INTRODUCTION
Monitoring is important to prevent anaethesia
complication
Sophisticated monitor available,
only to aid
not to fully dependent on them
Anaesthetist vigilance is the best
12. 2. NIBP
Measure blood pressure at set intervals
automatically by automated oscillometery.
Cuff size should cover 2/3 of arm
Small cuff for children
Too large (underestimate)
Too small (over estimate)
16. 1. IBP
Required in patient mandates for beat to beat
monitoring
Gold standard
Accuracy
measure the difference in IBP & NIBP not more than 5-
8mmHg
Radial Artery
Brachial Artery
Femoral Artery
Dorsalis Pedis Artery
17. Allen’s Test
Normal - <7s
Borderline – 7-14s
>15s – contraindicated
20. > INDICATION
Major surgeries where large fluctuations in haemodynamics
are expected.
Open heart surgeries.
Fluid management in shock.
As a venous access.
Parenteral nutrition.
Aspiration of air embolus.
Cardiac pacing.
Normal CVP is 3 to 10 cm of H20 (or 2-8 mmHg).
In children CVP is 3 to 6 cm of H20.
CVP more than 20 cm of H2O indicates right heart failure.
21. > TECHNIQUE OF CVP CATHETERIZATION (THROUGH
INTERNAL JUGULAR VEIN)
Seldinger technique
1. Patient lies in Trendelenburg position – to decrease
chance air embolism
2. The cannula with stylet is inserted at the tip of
triangle formed by two heads of sternomastoid and
clavicle. The direction of needle should be slightly
lateral and towards the ipsilateral nipple.
3. Once the internal jugular vein is punctured. Stylet is
removed and a J wire is passed through cannula
4. Now the CVP catheter is railroad over the J wire
5. The tip of catheter should be at the junction of superior
vena cava with right atrium – 15 cm from entry point
22.
23. > CVP IS INCREASED IN :
Fluid overloading
Congestive cardiac failure.
Pulmonary embolism
Cardiac tamponade
Intermittent positive pressure ventilation with PEEP
Constrictive pericarditis
Pleural effusion
Hemothorax
Coughing and straining
24. > CVP IS DECREASED IN :
Hypovolemia and shock
Venodilator
Spinal / epidural anaesthesia
General anesthesia – by causing vasodilatation
Low CVP + low BP = Hypovolemia
High CVP + low BP = pump failure
25. X ray chest is performed to check the position of
catheter and to exclude pneumothorax
Complication
Air embolism
Thromboembolism
Cardiac arrhymias
Pneumothorax/haemothorax/chylothorax
Cardiac perforation/cardiac tamponade
Sepsis – late complication
Trauma to brachial plexus, carotid A,phrenic N,airway
26. 3. PULMONARY ARTERY CATHETERIZATION
It is reserved only for very major cases in severely
compromised patients because cost, technical
feasibility, complications
Swan Ganz catheter - It is balloon tipped and flow
directed by pressure recording,pressure tracing and
catheter tip
Indicated by sudden rise in diastolic pressure
34. 1. PULSE OXIMETRY
Oxygen saturation – SpO2
Normal SpO2 - 97 – 98 %
Probe is applied at :
finger
nail bed,
toe nail bed ,
ear lobule,
tip of nose
Uses : detection of hypoxia intra/post operative
39. 2. CAPNOGRAPHY
It is the continuous measurement of end tidal
(expired) carbon dioxide (ETCO2) and its
waveform.
Normal: 32 to 42 mmHg (3 to 4 mmHg less than
arterial pCO2 which is 35 to 45 mmHg).
Principle : infrared light absorbed by carbon
dioxide
Important and sensitive monitoring
40.
41. 3. BLOOD GAS ANALYSIS
Precaution
Glass syringe is preferred for sampling
Syringes should be heparinized
Samples should be stored in ice
Sample from radial or femoral
Important in
Thoracic surgery
Hypothermia
Hypotensive anaesthesia
42. NORMAL VALUES ON ROOM AIR
pH - 7.38 to 7.42
Partial pressure of oxygen
(p02)
- 96 to 98 mmHg
Partial pressure of carbon
dioxide (pCO2)
- 35 to 45 mmHg
Bicarbonate (HCO3) - 24 to 28 mEq/L
Oxygen saturation (SpO2) - 95 to 98%
Base deficit -3 to + 3
43. CONT
Mixed venous oxygen in the best indicator of
cardiac output i.e., tissue oxygenation
Arterial oxygen is the better indicator of
pulmonary function.
pO2 -40 mmhg
pCO2 -46 mmhg
Oxygen saturation -75%
44. > OTHERS
LUNG VOLUMES – spirometer
OXYGEN ANALYSERS
Monitor actual value oxygen delivered
Fitted in inspiratory in limb of breathing circuit
Useful in closed circuit (use low flow oxygen)
AIRWAY PRESSURE MONITORING
It should less than 20 – 25cm H2O
Low pressure – disconnection
High pressure – obstruction in tube or circuit and
bronchospasm
45. 4. APNEA MONITORING (MONITORING OF
RESPIRATION)
Apnea is cessation of respiration for more than 10s.
Intubated patients
Capnography - Most sensitive and cost effective to detect apnea
Airway pressure monitor
Non intubated patients
Monitoring the airflow at nostrils (acoustic probe)
Detection of chest movements
Impedence plethysmography – chest is encircled by a coil
Transthoracic impedence pulmonometery
For intubated and non intubated patient
Pulse oximeter
47. > INDICATION
High incidence of intra-operative hypothermia
Usually in
Cardiac surgery
Infant
Children
Adult with burns
Febrile patient
Malignant hyperthermia patient
48. > TEMPERATURE MONITORING
Core temperature monitoring sites :
Esophagus
Pulmonary artery
Nasopharynx
Tympanic membrane – most accurate for brain
temperature
49. 1. HYPOTHERMIA
Hypothermia may be defined as core temperature less
than 35 ℃.
Mild : 28 – 35 ℃
Moderate : 21 – 27 ℃
Severe : <20 ℃
Most common thermal perturbation seen in anaesthesia
because :
Most anaesthetics are vasodilators, causing heat loss and
hypothermia
Cool room temperature
Cold intravenous fluids.
Evaporation
50. > SYSTEMIC EFFECTS OF HYPOTHERMIA
CVS
Bradycardia
Hypotension
Ventricular arrhythmias if temperature is less than 28°C
Respiratory system
Respiratory arrest below 23°C
O2 dissociation curve is shifted to left
Blood
Increased blood viscosity and platelet count
51. Acid base balance
Increased solubility of blood gases
Acidosis – increased lactic acid production d/t blood
stasis
Kidney
Decresed GFR
No urine output at 20°C
Endocrine system
Decreased adrenaline and nor-adrenaline
Hyperglycemia
52. > TREATMENT OF LNTRAOPERATIVE
HYPOTHERMIA
Warm intravenous fluids
Increase room temperature: The ideal operation
theatre temperature for adults is 21°C and for
the children 28°C
Cover the patient with blankets
Forced warm air by a special instrument ( Bair
Hugger airflow device)
53.
54. > USES OF INDUCED HYPOTHERMIA
Brain protection in cardiac arrest or neurovascular
surgeries. Brain can be protected for 10 minutes at
30°C
For tissue protection against ischemia in cardiac
surgeries done on heart lung machine
56. 1. NEUROMUSCULAR MONITORING
Adductor pollicis (ulnar nerve)
Others : Orbicularis oculi, Median nerve, Posterior tibial
nerve , Peroneal nerve
Required for :
Myasthenia gravis
Duchenne’s muscular dystrophy
Train of four (TO4) is the most useful method for clinical
monitoring.
In this 4 stimuli, each of 2 Hz for 2 sec are given and
recordings are taken.
Normal : amplitude height of fourth and first response will
be the same. T4/T1 = 1
57.
58.
59. Usage of depolarizing muscle relaxant – all 4 amplitude
will be decrease
Non depolarizing muscle relaxant – first there will be
decrease in T4/T1 ratio followed by fading which means
T4 response will disappear first then T3 and so on.
Assess reversal
Ratio 0.7 indicate adequate reversal
Recovery guaranteed at ratio 0.9
Usefull in dx phase II block
(patient on Sch show fading its pathgonominic of phase II
block)
60. > OTHER STIMULI USED FOR
NEUROMUSCULAR MONITORING
Single twitch
Tetanic stimulation
Post tetanic facilitation
Double burst stimulation (DBS 3,3 )
63. MONITORING DEPTH OF ANAESTHESIA
Clinically :
Signs and symptoms of light anaesthesia are:
Tachycardia.
Hypertension.
Lacrimation.
Perspiration.
Movement response to painful stimuli.
Tachypnea, breath holding, coughing, laryngospasm,
bronchospasm.
Eye movements.
Preserved reflexes
64. EEG
Patient evoked response
Bispectral index
Entropy – detection of abnormalities in EEG at
higher concentration of anaesthetic agents
65. EVOKED RESPONSE
Assessing the integrity of neuronal tissues during
surgeries
1. Somatosensory evoked pontential ( SSEP)
Any surgeries that can compromise vascular supply of
sensory tract
Spine surgeries, repair of thoracic and abdominal aorta
aneurysm, brachial plexus exploration and surgery of brain
area
2. Auditory evoked potential (AEP)
For procedures involving auditory pathways
Resection of acoustic neuroma and posterior fossa surgeries
3. Visual evoked potentials (VEP)
For procedures involving visual tracts
Optic glioma, pituitary tumours
66. ELECTROCEPHALOGRAM (EEG)
Other than measure depth of anesthesia , EEG also
can asses cerebral ischemia during neurovascular
surgeries – carotid endarterectomy
Effect of anesthetic agents and modalities on EEG
All inhalational and intravenous anesthetic agents
produces biphasic pattern on EEG
Lower dose – causing excitation( high frequency
and low amplitude waves).
High dose - causing depression (high amplitude
and low frequency waves)
67. 6. MONITORING BLOOD LOSS
Estimation of blood loss is done by weighing blood
soaked swabs, sponges (Gravimetric method) and
estimation of blood loss in suction bottle (Volumetric
method).
Most accurate method is colorimetric method.
On an average (a rough guide):
Fully soaked swab means 20 ml of loss.
Fully soaked sponge means 100 to 120 ml of loss.
A fist of clots means 200 to 300 ml of loss.
68.
69. 7. EXPIRED GAS ANALYSIS
There is multigas analyzer which measures
concentration of anaesthetic vapors like nitrous
oxide and inhalational agents like halothane,
isoflurane etc.
These are mass spectrometers and Raman gas
analyzers.