Short Textbook of Anesthesia Ajay Yadav
INDEX
A
Abnormalities of chest movements 8
Abnormal pain responses 272
ABO incompatibility 77
Acetylcholine receptor 123, figures 13.2, 13.3
Acetylcholinesterase 123
Acid-base management
Acidosis
Metabolic 294
Respiratory 293
Alkalosis
Metabolic 295
Respiratory 293
Diagnostic approach 293, flow chart 40.1 (page 294)
Interpretation of normal blood gas 293
Summary of changes in acid base disturbances, table 40.2 (page 295)
Acquired immunodeficiency syndrome (AIDS)
Anesthetic considerations 215
Transfusion related 78
Acromegaly, anesthetic considerations 209
Acupuncture 271
Acute lung injury (see ARDS)
Addison's disease 209
Adenotonsillectomy, anesthetic considerations 256
Adrenal dysfunctions, anesthetic management 208
Adrenaline (Epinephrine) 308, table 41.3 (page 309)
Intracardiac 307
Adductor pollicis 123
Adrenocortical suppression 110
Adult respiratory distress syndrome (ARDS)
Causes 291
Diagnosis 291
Management 291
Management of refractory ARDS 292
Air 105
Cylinder 17, table 2.1 (page 18)
Embolism (see venous air embolism)
Airway
Anatomy 3
Assessment 53
Block 162
Definite 37
Difficult 52
Assessment 53
Causes 52
Management 54, flow chart 5.1 (page 54)
Guedel 32, figure 3.1
Infraglottic devices 37
Endotracheal tubes (also see intubation) 37, figures 3.17A, 3.17B (page 38)
Management for cervical spine injury 56, 300, flow chart 5.2 (page 55)
Management for foreign body 298
Pressure, flow and volume monitoring 65
Pediatric 236
Resistance 6
Supraglottic devices 35
Aladin cassette vaporizer 21
Albumin 72
Aldrete score 148
Alfentanil 117
Allen's test 58
Alpha 2 agonists 118
Alvimopan 114, 118
Alzheimer disease, anesthetic management 196
Ambu bag resuscitator 32, figures 3.3 and 3.4 (page 33)
American Society of Anesthesiologists (ASA) grading 48
Amethocaine (Tetracaine) 155
Aminoglycosides (preoperative) 50
Amiodarone 308
Amnesia
As component of balance anesthesia 87
Inadequate 142
Amsorb 28
Amyotrophic lateral sclerosis, anesthetic management 197
Analgesia
Labor 233
Patient-controlled 271
Pre-emptive 271
Refrigeration 158
Analgesics, intravenous 268
Anaphylactic/anaphylactoid reactions 146
Anemia
Anesthetic management 216
As complication of nitrous oxide 95
Anesthesia
Balanced 87
Components 87
Dolorosa 272
For burn 260
For co-existing diseases (also see specific diseases)
Blood disorders 216
Cardiovascular diseases 183
Central nervous diseases 196
Electrolyte imbalances 204
Endocrinal diseases 206
Hepatic diseases 199
Immune-mediated diseases 214
Infectious diseases 214
Neuromuscular diseases 211
Psychiatric disorders 197
Renal diseases 202
Respiratory diseases 192
For day-care surgery (also see day care surgeries) 267
For ENT (also see ENT anesthesia) 255
For geriatrics (also see geriatric anesthesia) 242
For laparoscopy (also see laparoscopy) 248
For malignant hyperthermia 145
For neurosurgery (also see neurosurgical anesthesia) 223
For obese patients (also see bariatric anesthesia) 245
For obstetrics (also see obstetric anesthesia) 230
For ophthalmic surgeries (also see ophthalmic anesthesia) 252
For orthopedics (also see orthopedic anesthesia) 262
For pediatrics (also see pediatric anesthesia) 236
For remote locations 265
For trauma (also see anesthesia for trauma) 258
High altitude 265
History 83
Low flow 27
Machine 15 (also see anesthesia machine), figure 2.1 (page 15), 2.2 (page 16) and 2.3 (page 16)
Protocol (for normal patient) 87
Stages, table 9.1 (page 88)
Work station 15, figure 2.3 (page 16)
Anesthesia machine 15, figures 2.1 to 2.3 (pages 15, 16)
Checking of 29
Negative pressure test 30
Positive pressure test 30
High pressure system 15
Intermediate pressure system 19
Low pressure system 19
Mechanics of gas flow 22, figure 2.13 (page 23)
Safety features 30
Ventilators 22
Anesthetic tether 91
Anion gap 294
Ankle block 162
Ankylosing spondylitis, anesthetic management 214
Antibiotics
For prophylaxis 51
Preoperative 50
Anticholinergics (as premedication) 51
Anticholinesterases
For reversal of neuromuscular block 131
Mechanism of action 131
Preoperative 49
Anticoagulants
And central neuraxial blocks 177
Preoperative 48,49
Antidepressants
Preoperative 49
Antiemetics
For preoperative prophylaxis 51
For treatment of nausea and vomiting 143
Antihypertensives
Preoperative 49,190
Antiplatelets
And regional anesthesia 177
Preoperative 49
Antitubercular
preoperative 50
Aortic regurgitation, anesthetic management 186
Aortic stenosis (AS), anesthetic management 186
Apnea
Monitoring for non-intubated 64
Arterial cannulation
Complications 58
Uses 58
Arrhythmias
As complication 140
Management of non-shockable rhythms 302, flow chart 41.3 (page 304)
Management of shockable rhythms 301, flow chart 41.2 (page 302)
Aspirin
And regional anesthesia 177
Preoperative 49
Aspiration
Foreign body and segments involved 4
Management of high risk cases 137
Of gastric contents 136
Predisposing factors 137
Risk factors 137
Asthma, anesthetic management 193
Asystole 304
Atelectasis 139
Atracurium 129
Atropine
As premedication 51
For bradycardia after spinal 170
Atypical pseudocholinesterase 126
Augmented inflow effect 91
Autologous blood transfusion 79
Autonomic dysfunction 197
Awareness 142
Ayre's T piece 26, figure 2.14, table 2.4
B
Backache
As complication of spinal anesthesia 173
Management 271
Bag and mask ventilation
Contraindications 137 (also see appendix 313)
Bain circuit 24, figures 2.14 and 2.17, table 2.4 (pages 2426)
Barbiturates 106
Bariatric anesthesia 245
Barotrauma 283
Barylime 27
Reaction with inhalational agents 28
Basic life support (BLS) 297, table 41.1(page 298), flow chart 41.1 (page 299)
Benzocaine 155
Benzodiazepines
Antagonist (Flumazenil) 112
Metabolism 111
Pharmacokinetics, table 12.1 (page 111)
Systemic effects 111
Uses 111
Benzylisoquinoline compounds (also see individual agents) 128
Bernoulli's law 11
Beta blockers 183
Bier's block (Intravenous regional block) 161
Biliary obstruction, anesthetic management 200
Bispectral index monitoring 69
Blocks (also see individual blocks)
Head and neck 162
Lower limb 162
Thorax and abdomen 162
Upper limb 160
Blood, artificial 79
Blood gas analysis 65 (also see acid base disturbances)
Blood gas partition coefficient (B/G Coeff,) 91, table 10.2 (page 91)
Blood loss
Allowable 216
Monitoring 69
Treatment (see management of shock 285)
Blood pressure
Invasive 58
Monitoring 57
Blood salvage and reinfusion 80
Blood transfusion
Autologous 79
Changes in stored blood 76
Complications 77
Infectious 78
Noninfectious 78
Transfusion reactions 77
Component therapy 76
Cryoprecipitate 77
Fresh frozen plasma 76
Frozen RBCs 76
Packed red blood cells 76
Platelets concentrate 77
Emergency 76
Grouping and compatibility 75, table 7.2 (page 75)
Indications 75
Massive 76
Storage 76
Boyle's law 11
Boyle's machine (see anesthesia machine)
Brachial plexus block
Axillary approach 161
Infraclavicular approach 161
Interscalene approach 160
Supraclavicular approach 160
Brain death 308
Breath holding time 47
Breathing (Ventilation) in CPR 300
Breathing bag 24, figure 2.16 (page 25)
Breathing circuits
Checking 30
Components 27, figure 2.19 (page 27)
Carbon dioxide absorbents
  Amsorb 28
  Barylime 27
  Lithium hydroxide 28
  Sodalime 27
Flow sensors 28
Oxygen analyzers 28
Valves 28
Comparison between closed and semiclosed circuits table 2.5 (page 29)
Factors affecting carbon dioxide absorption 29
Open 22
Semiclosed (Mapleson circuits) 23, figure 2.14 (page 24), table 2.4 (page 26)
Ayre's T piece 26, figure 2.14 (page 24), table 2.4 (page 26)
Hafina 26
Humprey ADE 26
Single limb (universal F) 29
Breuer Lockhart reflex 139
Bronchial
Intubation 63
Tree 4
Bronchopulmonary segments 4
Bronchoscopy, anesthetic management 256
Bronchospasm
As perioperative complication 139
Management of intraoperative bronchospasm 194
Bubble oxygenators 42
Bullard laryngoscope 34, figure 3.7 (page 34)
Bupivacaine (Sensoricaine, Marcaine) 156
Buprenorphine 117
Burns
Anesthetic management 260
Emergency management 260
Fluid management 260
Butorphanol 118
C
Calcium
Disorders 204
In CPR 307
Cancer pain 272
Capnography 62
Nasal 64
Uses 62
Waveform 62, figures 6.1 (page 62) and 6.2 (pages 63, 64)
Capnothorax 248
Carbon dioxide 105
Absorbents 27
Cylinders, table 2.1 (page 18)
Dissociation curve 8
Transport in blood 8
Carbon monoxide (CO) poisoning 292
Cardiac arrest (also see Cardio pulmonary resuscitation)
As complication in perioperative period 141
Causes 297
Management 297
Cardiac failure, anesthetic considerations 188
Cardiac implanted electronic devices, anesthetic considerations 189
Cardiac massage
Open chest 307
Physiological considerations 301
Cardiac transplant patients, anesthetic considerations 189
Cardiomyopathies, anesthetic considerations 188
Cardiopulmonary resuscitation (CPR)
Adrenaline in CPR 308, table 41.3 (page 309)
Advanced cardiovascular life support (ALS) 298, table 41.1 (page 298)
Airway management 298
Arrhythmia management
Nonshockable 302, flow chart 41.3 (page 304)
Basic life support (BLS) 297, table 41.1 (page 298), flow chart 41.1(page 299)
Breathing management 300
Circulation (cardiac massage) 300, figure 41.1 (page 300)
Complications 307
Comparison of 2010 and 2015 guidelines, table 41.2 (page 309)
Compression ventilation ratios 301
In pregnancy 307
Monitoring performance 301
Newborn 306
Newer techniques/variations 304
Open chest massage 307
Outcome 307
Pediatric 305
Postcardiac arrest care 305
Routes of drug administration 307
Summary, table 41.4 (page 309)
Caudaequina syndrome 172
Caudal block (Epidural sacral block) 176
Celiac plexus block 274
Cement implantation syndrome 263
Centrally acting muscle relaxants 133
Central neuraxial blocks (also see spinal and epidural anesthesia)
Advantages over GA 165
Applied anatomy 164
Contraindications 177
Systemic effects 166
Central supply of oxygen and nitrous oxide 19
Central venous pressure (CVP)
Complications 59
Indications 58
Monitoring 58
Technique 59
Cerebral blood flow (CBF) 223
Cerebral metabolic rate (CMR) 223
Cerebral protection 308
Cerebrospinal fluid (CSF) 165
Cerebrovascular accident, anesthetic management 196, 227
Cervical plexus block 162
Cervical spine
Airway management 56, 300, flow chart 5.2 (page 55)
Cesarean section
Anesthetic management 231
For heart disease patients 233
For PIH patients 233
Charle's law 11
Chest movements
Abnormalities 8
Child-Pugh classification 199
Chloroform 102
Chloroprocaine 155
Chronic obstructive pulmonary disease (COPD)
Anesthetic considerations 194
Critical care management 292
Circuits (see breathing circuits)
Cis-atracurium 129
Clonidine 118
Clopidogrel
Preoperative 49
Closed circuits- see breathing systems
Co-oximeters 61
Coagulation disorders, anesthetic management 218
Coarctation of aorta, anesthetic considerations 187
Cocaine 155
Colloids 72
Combined spinal-epidural anesthesia (CSE) 176
Combitube 37
Complex regional pain syndrome (CRPS) 272
Complications (perioperative) of general anesthesia 136
Concentration effect 91
Congenital heart diseases, anesthetic considerations 187
Congestive heart failure (CHF), anesthetic management 188
Controlled hypotension 140
Convulsions
As complication of GA 141
Cotmack and Lehane classification for laryngoscopy 53, figure 5.2 (page 53)
Cranial nerve palsies
With spinal 172
With trielene 102, 142
Cricoid pressure 138
Cricothyrotomy 42
Critical care management (see Intensive care management)
Critical temperature 11
Cryoprecipitate 77
Crystalloids 71
Cuff of endotracheal tube 37
Cushing syndrome, anesthetic considerations 209
Cyclodextrins (sugammadex) 132
Cyclopropane 102
Cylinders 15
Carbon dioxide table 2.1 (page 18)
Cyclopropane table 2.1 (page 18)
Heliox 17, table 2.1 (page 18)
Nitrous oxide, figure 2.5 (page 17), table 2.1 (page 18)
Valves 17
D
D-tubocurare 128
Day-care surgeries
Advantages 267
Anesthesia 268
Discharge criteria 269
Patient and procedure selection 267
Postoperative complications 268
Postoperative instructions 269
Preoperative assessment and premedication 267
Dead space 7
And anesthesia 7
Deep vein thrombosis, incidence with spinal 166
Defibrillation 301
Delirium 142
Depolarizing muscle relaxants 124
Depression, anesthetic management 197
Depth of anesthesia 69
Desflurane
Anesthetic properties 99
Metabolism 99
Physical properties 98
Systemic effects 99
Uses 99
Dexmedetomidine 118
Dextrans (Lomodex) 72
Dextrose normal saline (DNS) 72
Dezocine 118
Diabetes mellitus, anesthetic management 206
Diameter index safety system (DISS) 19
Diaphragmatic hernia, anesthetic management 240
Diazepam 111
Dibucaine (Cinchocaine) 157
Dibucaine number 126
Differential block 154
Difficult airway 52
Assessment 53
Causes 52
Management 54, flow chart 5.1 (page 54)
Diffusion hypoxia (Fink effect) 92
Discharge criteria
After day-care surgery 268
From postanesthesia care unit 148
Disseminated intravascular coagulation (DIC) (transfusion related) 79
Dissociative anesthesia 112
Disulfiram 50
Diuretics 50
Double lumen tubes 39, figure 3.19 (page 40)
Complications 40
Confirmation of position 40
Indications 39
Down syndrome, anesthetic management 240
Doxacurium 129
Droperidol 120
Drug abuse, anesthetic management 198
Dual block 127
Duchenne's dystrophy (Pseudohypertrophic muscular dystrophy), anesthetic management 212
E
Ear surgeries, anesthetic management 256
Echocardiography 60
Transesophageal 60
Transthoracic 60
Edrophonium 132
Electrical hazards 147
Precautions to prevent 147
Electrical impendence pulmonometry 64
Electrocardiography (ECG) 57
Electroconvulsive therapy 108, 198
Electroencephalogram (EEG) 68
Effect of anesthetic agents 68
To monitor depth of anesthesia 69
Electrolyte imbalances 204
Embolism
Air 226
Fat 262
Pulmonary 139
Endogenous opioid 118
Endotracheal drug administration 307
Endotracheal tubes (also see intubation) 37, figures 3.17A and B (page 38)
And dead space 38
Confirmation of position 40
Cuff 37
Deciding length 39
Deciding size 38
Double lumen 39, figure 3.19 (page 40)
Microlaryngeal 39
RAE (Oxford) 39
Spiral embedded (flexometallic) 39
Enflurane 100
ENT anesthesia
Anesthesia for adenotonsillectomy 256
Anesthesia for bronchoscopy 256
Anesthesia for nasal surgeries 256
Anesthesia for panendoscopy (Microlaryngeal surgeries) 255
Laser concerns 256
Entonox 96
Entropy 69
Ephedrine 170
Epidural (Extradural, Peridural) anesthesia
Advantages over spinal 175
Comparison with spinal, table 17.1 (page 167)
Contraindications 177
Disadvantages over spinal 175
Drugs
Local anesthetics 174, table 17.2 (page 174)
Opioids 174
Epidural needles 174
Factors effecting level of block 175
Indications 174
Technique 174
Site of action of drugs 174
Epidural space
Anatomy 165
Venous plexus (plexus of Batson) 165
Epilepsy
Anesthetic management 196
Causative agents 144
Esters-local anesthetics 151
Ether 100
Advantages 100
Disadvantages 100
Etidocaine 157
Etomidate
Advantages 110
Disadvantages 110
Uses 110
Eutectic mixture of local anesthetics (EMLA) cream 157
Evoked responses 68
Expiratory reserve volume 10
Expired gas analysis 62
Extracorporeal oxygen delivery devices 42
Extubation 41
F
Facemask 32, figure 3.2 (page 32)
Fail safe valve 19
Familial periodic paralysis, anesthetic considerations 212
Fascia iliaca block 162
Fasting instructions 50
Fat embolism 262
Febrile reactions, post-transfusion 78
Femoral block 162
Fentanyl 117
Fiberoptic laryngoscope 34, figure 3.9 (page 34)
Fibromyalgia 273
Filling ratio (Filling Density) 17
Fire
During laser surgery 256
Hazards 147
Precautions to prevent 147
Flow
Of gases 11
Laminar 11
Turbulent 11
Volume Loops 10
Fluids
Colloids 72
Crystalloids 71
Difference between crystalloids and colloids, table 7.1 (page 71)
For burn 75
For cardiac patient 74
For cerebral edema 74
For liver failure 74
For pulmonary edema 74
For renal failure 74
For sepsis 75
For shock 75
Guiding parameters 74
In CPR 307
Management (for perioperative period) 73
Routes for administration 75
Flumazenil 112
Fluoride-induced nephrotoxicity 93, table 10.3 (page 93)
Foreign body
Aspiration 4
Segments involved 5
Fresh frozen plasma (FFP) 76
Frozen RBCs 76
Functional residual capacity (FRC) 10
G
G6PD deficiency 218
Gallamine (Flexidil) 129
Gamma cyclodextrins 132
Ganglion impar block 274
Gantacurium 130
Gastric tonometry 60
Gelatins (Hemaccel) 72
General anesthesia
Complications 136
Anaphylactic 146
Cardiovascular 140
Gastrointestinal 142
Fires 147
Hepatic 143
Mortality 136
Neurological 141
Ocular 146
Occupational 147
Pain 143
Position related 146
Renal 143
Respiratory 136
Stages 88, table 9.1 (page 88)
Thermal 143
Components 87
Protocol 87
Geriatric anesthesia
Anesthetic management 242
Physiological changes 242
Postoperative cognitive dysfunction 243
Postoperative delirium 243
Glasgow coma scale 226
Global warming by inhalational agents 94
Glucose solutions 72
Glycopyrrolate
As component of reversal 132
As premedication 51
Goal directed therapy for fluids 74
Goldman vaporizer 21
Graham's law 11
Granulocyte precipitate 77
Guedel airway 32, figure 3.1 (page 32)
Guillain-Barré syndrome, anesthetic considerations 197
H
Hagen-Poiseuille law 11
Halothane
Anesthetic properties 97
Contraindications 98
Drug interactions 98
Metabolism 97
Physical properties 96
Systemic effects 97
Halothane hepatitis 97
Headache
Anesthetic management 196
Post-spinal 171
Head injury
Anesthetic management 225, 226
Heart failure, anesthetic considerations 188
Heat and moisture exchanger 43, figure 3.20 (page 43)
Heidbrinkflowmeter 20
Heimlich maneuver 298
Heliox 105
Cylinder 17, table 2.1 (page 18)
Helium 105
Hematopoietic system and inhalational agents 93
Hemolytic reactions 77
Hemolytic reactions 77, 78
Hemophilia (see coagulation disorders)
Heparin (standard and low molecular weight)
And regional anesthesia 177
Preoperative 48
Hepatic
Anesthetic management for hepatic diseases 199
Blood flow and inhalational agents 93
As complications in perioperative period 143
Hepatitis (post-transfusion) 78
Herbal medications (preoperative) 50
Herpetic neuralgia 272
Hextend 73
Hiccup 8
High altitude, anesthetic considerations 265
High flow oxygen delivery devices 42
High pressure system (of anesthesia machine) 15
History of anesthesia 83
Hoffman degradation 129
Hudson mask 42
Human immunodeficiency virus (HIV)
Anesthetic considerations 215
As complication of transfusion 78
As occupational hazard 147
Humidification devices (humidifiers) 43, figure 3.20 (page 43)
Humprey (ADE) semiclosed circuit 26
Hydrodynamics of regurgitation 137
Hydroxyethyl starch 73
Hyperbaric oxygen 104
Hyperbaric oxygen chamber, anesthetic considerations 265
Hypercalcemia, anesthetic considerations 204
Hypercarbia 140
Hyperkalemia, anesthetic considerations 204
Hypermagnesemia, anesthetic considerations 204
Hypernatremia, anesthetic considerations 204
Hypertension
Anesthetic management 189
As complication in perioperative period 140
Hyperthermia
Causes 143
Malignant 144
Hyperthyroidism, anesthetic management 207
Hypertonic Saline 72
Hypertrophic obstructive cardiomyopathy 188
Hypocalcemia, anesthetic considerations 204
Hypocapnia 140
Hypokalemia, anesthetic considerations 204
Hypomagnesemia, anesthetic considerations 204
Hyponatremia, anesthetic considerations 204
Hypotension (also see shock)
Anesthetic management 190
As complications in perioperative period 140
As complications of spinal anesthesia 169
Controlled 140
Hypothermia
As complication in perioperative period 143
Definition 65
Induced 66
Systemic effects 66
Treatment 66
Hypothyroidism, anesthetic management 208
Hypoventilation 138
Hypoxia
Causes 136
Classification 103
Systemic effects 103
Treatment 103
Hypoxic pulmonary vasoconstriction (HPV) 9
I
I-gel LMA 36, figure 3.14 (page 37)
Ilioinguinal and iliohypogastric nerve block 162
Impedance plethysmography 64
Inflammability of inhalational agents 94
Inhalational agents (also see individual agents)
Absorption in circuits 92
Amnesia 94
Analgesia 94
Blood gas coefficient 91, table 10.2 (page 91)
Classification 89
CNS effects 93, 224
Effect on uterus 94
Factors effecting uptake 90, 91
Fluoride production, table 10.3 (page 93)
In common use 94
Inflammability 94
Mechanism of action 89
Metabolism 92
Not in current use 100
Ozone destruction 94
Physical properties, table 2.3 (page 22)
Potency 90
Reaction with sodalime and barylime 94
Summary of anesthetic properties, table 10.4 (page 100)
Summary of systemic effects, table 10.5 (page 101)
Systemic effects 92
Teratogenicity 94
Uptake and distribution 90
Inotropes 287
Insulin (dose adjustments before surgery) 206
Intensive care management
Mechanical ventilation (also see mechanical ventilation) 278
Nutritional therapy 287
Intercostal nerve block 274
Intermediate pressure system of anesthesia machine 19
Intra-arterial thiopentone injection 108
Intracardiac adrenaline 307
Intracranial tension (ICT)
Anesthetic management for raised ICT 225
Methods to decrease 223
Signs and symptoms 223
Intraocular pressure (lOP) 252
Intraosseous route for fluid administration 75, 307
Intravenous Anesthetics (also see individual agents)
Classification 106
Barbiturates 106
Nonbarbiturates 109
CNS effects 224
History 84
Summary of systemic effects, table 12.2 (page 119)
Summary of anesthetic effects, table 12.3 (page 120)
Uses 106
Intravenous regional block (Bier's block) 161
Intubating LMA (fastrach) 36, figure 3.11 (page 36)
Intubation
Complications 41
Contraindications 40
Difficult
Management 54, flow diagram 5.1 (page 54)
Nasal 40
Reflex response 39
Technique 37, figure 3.18 (page 39)
Invasive blood pressure (IBP) 58
Ischemic heart diseases (IHD), anesthetic management 183
Isoflurane
Anesthetic properties 98
Physical properties 98
Systemic effects 98
J
Jackson Rees breathing circuit 26, figure 2.14 (page 24), table 2.4 (page 26)
Jet ventilation 255
K
Keratitis 146
Ketamine
Advantages 113
Anesthetic properties 112
Contraindications 113
Disadvantages 113
Pharmacokinetics 112
Physical properties 112
S-isomer 114
Site of action 112
Systemic effects 112
Uses 113
L
L-cysteine 132
Labor analgesia 233
Lack system 24
Laminar flow 11
Lamotrigine 49
Laparoscopy
Anesthetic management 250
Complications 248
Contraindications 250
Gases used for insufflation 248
Pathophysiological effects 248
Laryngeal mask airways (LMA)
Classical 35, figure 3.10 (page 35)
Complications 35
Contraindications 36
Indications 35
Second generation 36
Intubating (fastrach) 36, figure 3.11 (page 36)
Size 35
Laryngoscopes
Direct rigid 33
Macintosh 33, figure 3.5 (page 33)
Magill 33
Miller 33
Flexible 34, figure 3.9 (page 34)
For infants and newborns 33
Indirect rigid 33
Bullard 34, figure 3.7 (page 34)
Laryngoscopy
Complications 35
Grading 53
Reflex responses 39
Larynx
Anatomy 3, figure 1.1 (page 3)
Pediatric (Anatomical differences from adults) 236
Paralysis of nerves 4
Laser in ENT surgeries 256
Left to right-shunts, anesthetic considerations 187
Levobupivacaine 157
Levodopa 49
Lignocaine (Xylocaine, Lidocaine) 155
Lithium 49
Lithotomy 146
Local anesthetics (also see individual agents)
Causes of failure 158
Classification 151
Commercial preparations 155
Differential block 154
Factors effecting duration 153
Factors effecting onset 153
Mechanism of action 152
Metabolism 154
Methods of local analgesia 157
Potency 153
Sensitivity to nerve fibers 152
Summary of properties, table 15.2 (page 158)
Systemic absorption 153
Systemic effects 154
Toxicity 154
Lorazepam 111
Low flow oxygen delivery devices 42
Low pressure system of anesthesia machine 30
Lumbar sympathetic block 274
Lung compliance 10
Lung function test (see pulmonary function test)
Lung volumes 9, figure 1.5 (page 9)
M
Macintosh laryngoscope 33, figure 3.5 (page 33)
Magill circuit 23, figure 2.15 (page 25), table 2.4 (page 26)
Magill laryngoscopes 33
Maintenance fluids (for perioperative period) 73
Malignant hyperthermia
Anesthetic management for susceptible patients 145
Causative agents 144
Clinical features 144
Management of 145
Screening for 145
Mallampati grading for airway assessment 53, figure 5.1 (page 53)
Mania, anesthetic considerations 198
Manual removal of placenta, anesthetic management 234
Mapleson circuits 23, figure 2.14 (page 24), table 2.4 (page 26)
Mary Carterall mask 42
Mask
Face 32
Non-rebreathing 42
Massive blood transfusion 76
Match test 9
McCoy laryngoscopes 33, figure 3.6 (page 34)
Mechanical ventilation
Complications 283
Indications 278
Modes of ventilation 279, figures 40.140.6 (pages 279282)
Monitoring 284
Noninvasive positive pressure ventilation 282
Ventilators 278
Weaning 283
Mechanics of gas flow in anesthesia machine 22, figure 2.13 (page 23)
Meninges 165
Mephentermine 170
Mepivacaine 156
Metabolic acidosis 294
Metabolic alkalosis 295
Methemoglobinemia
With local anesthetics 155
Methohexitone 108
Methoxyflurane 102
Metocurine 128
Meyer Overton Rule 89
Microlaryngeal surgeries (MLS), anesthetic management 255
Midazolam 111
Miller Laryngoscopes 33
Minimum alveolar concentration 90, table 10.1 (page 90)
Factors effecting 90
Minitracheostomy 42
Mitral regurgitation, anesthetic management 185
Mitral stenosis, anesthetic management 185
Mitral valve prolapse, anesthetic management 185
Mivacurium 129
Modification in pre-existing medical therapy 48
Monitored Anesthesia care 268
Monitoring
Advance 57
Airway pressure, flow and volume 65
Apnea 64
Blood loss 69
Cardiovascular 57
Central nervous system 68
Clinical 57
Depth of Anesthesia 69
Expiratory gases 62
In ICU 284
Neuromuscular 66
Respiratory 61
Temperature 65
Monitoring of CPR 301
Multiple sclerosis, anesthetic management 197
Muscle blockade sequence 123
Muscle relaxants (also see individual agents)
Altered response in diseases, table 13.2 (page 131)
Classification 124
Depolarizing 124
Mixed oniumchlorofumrate 130
Nondepolarizing 127
Centrally acting 133
Difference between depolarizers and nondepolarizers, table 13.1 (page 124)
Summary of pharmacology, table 13.3 (page 133)
Muscles of respiration 6
Muscular dystrophies
Anesthetic management 212
Response to muscle relaxants 211, table 13.2 (page 131)
Myasthenia gravis
Anesthetic management 211
Response to muscle relaxants 211, table 13.2 (page 131)
Myasthenic syndrome (Eaton-Lambert syndrome)
Anesthetic management 212
Response to muscle relaxants 212, table 13.2 (page 131)
Myocardial ischemia/infarction
Anesthetic management 183
As complication in perioperative period 141
Treatment of intraoperative infarction 184
Myofascial pain syndrome 273
Myotoniadystrophica, anesthetic management 213
N
Nalbuphine 118
Nalmefene 118
Naloxone 118
Naltrexone 118
Narcotrend 69
Nasal cannula 42
Nasal intubation 40
Contraindications 40
Indications 40
Nasal surgeries, anesthetic management 256
Nausea and vomiting
As complication of GA 142
As complication of spinal 170
Nebulizers 43
Needle cricothyrotomy 42
Neostigmine 132
Nephrotoxicity (fluoride induced) 93
Nerve blocks (also see individual blocks)
Contraindications 163
Of abdomen and thorax 162
Of head and neck 162
Of lower limb 162
Of upper limb 160
Neuroleptanalgesia 120
Neuroleptanesthesia 120
Neuromuscular block
Factors antagonizing 130
Factors prolonging 130
Reversal 131
Neuromuscular junction
Physiology 122, figure 13.1 (page 122)
Neuromuscular monitoring
Modalities 68
Sites 66
Neuropathic pain 272
Neuropathies
As complication after general anesthesia 142
Neurosurgical anesthesia
Anesthetic management for awake craniotomies 228
Anesthetic management for conditions with raised ICT 225
Anesthetic management for head injury 225, 226
Anesthetic management for posterior fossa surgery 226
Anesthetic management for spine surgeries 228
Anesthetic management for stroke 227
Cerebral physiology and pharmacology 223
Fluids 224
Intracranial tension 223
Monitoring 225
Newborn CPR 306
Nitric oxide 105
For ARDS 292
Nitroglycerine for controlled hypotension 141
Nitrous oxide
And closed spaces 95
And ozone depletion 96
Anesthetic properties 94
Central supply 19
Impurities 96
Metabolism 95
Physical properties 94
Side effects 95
Systemic effects 95
Non-invasive positive pressure ventilation (NIPPV) 282
Nonbarbiturates 106
Nondepolarizing muscle relaxants (NDMR) 127
Classification 127
Reversal 131
Uses 127
Nonobstetric surgery during pregnancy 234
Noradrenaline for shock 287
Normal saline 72
Normovolemic hemodilution 80
NSAIDs
Preoperative 49
Nutritional support in ICU 287
Complications, table 40.1 (page 288)
Enteral 287
Total parenteral (TPN) 287
O
Obesity, anesthetic management 245
Obstetric anesthesia
Anesthesia for cesarean section 232
Anesthesia for manual removal of placenta 234
Anesthesia for nonobstetric surgery during pregnancy 234
Effect of anesthetic drugs/technique of uteroplacental circulation 231
Physiological changes of pregnancy 230
Transfer of anesthetic drugs to fetal circulation 231
Obstructive sleep apnea, anesthetic management 257
Occupational hazards 147
Ocular
Anesthesia 252
Complications after GA 146
Oculocardiac reflex 252
Ondansetron 51
One lung ventilation 39
Ophthalmic anesthesia
General anesthesia 253
Regional blocks (peribulbar and retrobulbar) 252, 253
Opioids (also see individual agents)
Agonist-antagonist 117
Agonists 116
And receptor interaction 114
Antagonist 118
Peripheral 118
Classification 114
Endogenous 118
Epidural 174
For acute pain 270
For cancer pain 272
For pediatric pain 239
For thoracic pain 193
Intrathecal 168
Mechanism of action 115
Pharmacokinetics 116
Receptors 114
Systemic effects 115
Uses 114
Oral anticoagulants 48
Oral contraceptives 48
Oral hypoglycemics 48
Orthopedic surgery
Choice of anesthesia 263
Complications 262
Oxygen
Analysers 28, 65
Central supply 19
Checking accuracy 30
Concentrator 103
Deficiency 103
Delivery devices 42
Extracorporeal 42
High flow 42
Low flow 42
Dissociation curve 7, figure 1.3 (page 8)
Failure alarm 19
Flush 19
Hyperbaric 104
Hyperbaric 104
Liquid 16
Nitrous oxide proportioning system 20
Oxygen carrier, synthetic 79
Physical properties 103
Preparation 103
Saturation
Arterial 61
Mixed venous 61
Storage 15, 103
Toxicity 104
Transport in blood 8
Oxygenation
Regional 62
Oxygenators 42
Ozone destruction by inhalational agents 94
P
Pacemakers and anesthetic considerations 189
Packed cell volume (PCV) 76
Pain (also see individual conditions)
Acute pain management 270
As complication in perioperative period 143
Assessment 270
Chronic pain management 271
Painless labor 233
Pancuronium 128
Paracervical block 234
Paradoxical respiration 8
Paravertebral block 162
Parkinson's disease, anesthetic management 196
Parotid surgery, anesthetic management 257
Pediatric
Anesthesia 236
Anesthetic considerations for neonatal emergencies 240
Anesthetic considerations for prematures 240
Circuits 26
CPR 305
Fasting recommendations 238
Fluids 238
General anesthesia 238
Pain management 239
Physiological and anatomical differences from adults, table 29.1 (page 236)
Regional anesthesia 173, 239
Penile block 162
Pentazocine 117
Perfluorocarbon emulsions 79
Peribulbar block (Pericone block) 252
Pericardial diseases, anesthetic considerations 189
Peripheral (outside OT), anesthetic considerations 265
Peripheral nerve blocks (also see individual blocks) 160
Peripheral neuropathies 142
Peritonsillar abscess and Ludwig angina 256
Perivascular (3 in 1) block 162
Pethidine (Meperidine) 116
Phantom limb 272
Phase II block 127
Pheochromocytoma, anesthetic considerations 208
Phrenic nerve block 162
Physics related to anesthesia 11
Pin Index System 18, table 2.2 (page 18)
Pipecuronium 128
Piritamide 116
Plasmalyte 72
Platelet concentrates 77
Platelet disorders, anesthetic considerations 217
Plethysmography
For apnea monitoring 64
For pulmonary function test 10
Pleural pressures 10
Plexus of Batson 165
Pneumonectomy, operative criteria 195
Pneumothorax, as complication of GA 140
Polycythemia, anesthetic management 217
Porphyria, anesthetic considerations 218
Position-related complications 146
Postanesthesia care unit (PACU)
Discharge criteria 148
Postanesthesia discharge scoring system (PADS) 148
Post cardiac arrest care (Post Resuscitation Life Support) 305
Posterior fossa surgery 226
Postherpetic neuralgia 272
Postoperative
Cognitive dysfunction 142
Pain management 270
Postspinal headache 171
Potassium disturbances 204
Poynting effect 11
Pregnancy-induced hypertension (Pre-eclampsia), anesthetic management 233
Prematures, anesthetic considerations 240
Premedication 50
Preoperative
Assessment (preanesthesia check up) 47
Fasting 50
Investigations 47
Modifications in drug therapy 48
Risk stratification 48
Preoxygenation 87
For rapid sequence induction 138
Pressure
Gauge 18
Regulator/Reducing valves 19
Relief valve 24
Prilocaine 156
Procaine 155
Prolonged apnea after succinylcholine 126
Prone position 147
Propofol
Advantages 110
Contraindications 110
Disadvantages 110
Metabolism 109
Pharmacokinetics 109
Physical properties 109
Systemic effects 109
Uses 109
Proseal LMA 36, figure 3.12 (page 36)
Prosthetic heart valves, anesthetic considerations 186
Pseudocholinesterase
Atypical 126
Low levels 126
Psychiatric disorders, anesthetic considerations 197
Pudendal nerve block 234
Pulmonary
Artery catheterization 59
Artery occlusion pressure (pulmonary capillary wedge pressure) 60
Aspiration of gastric contents 136
Atelectasis 139
Edema
Cardiogenic (hemodynamic) 290
Noncardiogenic (ARDS) 290
Embolism 139, 263
Function test 9
Pulseless electrical activity (PEA) 302
Pulse oximetery 61
Pyloric stenosis, anesthetic management 240
Pyridostigmine 132
R
Rapacuronium 128
Recovery, delayed 141
Reflex response to laryngoscopy and intubation 39
Reflex sympathetic dystrophies 272
Remifentanil 117
Renal
Anesthetic management 202
Complications in perioperative period 143
Effect of inhalational agent 90
Replacement fluids (for perioperative period) 73
Reservoir (Breathing) bag, figure 2.16 (page 25)
Residual volume 10
Respiration
Muscles of 6
Paradoxical 8
Regulation 6
Respiratory
Acidosis 293
Alkalosis 293
Bronchial tree 5
Respiratory failure
Classification 277
Management 278
Respiratory tract infection, anesthetic considerations 194
Restrictive lung disease, anesthetic considerations 194
Retrobulbar block 253
Retrolental fibroplasia 104
Reversal of neuromuscular block 132
Cause of inadequate reversal 133
Drugs 131, 132
Signs of adequate reversal 132
Rheumatoid arthritis, anesthetic management 214
Rhythms in cardiac arrest 297
Right to left shunts, anesthetic considerations 187
Ringer lactate solution 71
Rocuronium 128
Ropivacaine 157
Rotameter 19, figures 2.9 and 2.10 (page 20)
Safety features 20
S
Saddle block 173
Scavenging system 22
Schizophrenia, anesthetic management 198
Scleroderma, anesthetic considerations 214
Second gas effect 92
Segments of lungs involved in aspiration 4
Sellicks maneuver 138
Semiclosed circuits 23
Semon's law 4
Sepsis 290
Sevoflurane
Anesthetic properties 99
Disadvantages 99
Physical properties 99
Systemic effects 99
Shivering
As complication after general anesthesia 143
As complication after spinal anesthesia 170
Shockable rhythms 301
Shock
Anesthetic management 190
Classification 285
Clinical features 285
Definition 284
Management 285
Prediction of outcome 287
Shock index/modified shock index 287
Shunts
Left to right 187
Right to left 187
Sickle cell disease, anesthetic management 217
Sigh 8
Sitting position 146
Sleep apnea syndrome 245
Smoking 49
Sodalime 27
Reaction with inhalational agents 28
Sodium bicarbonate
For acidosis 295
For CPR 308
Sodium Disturbances 204
Sodium nitroprussid for controlled hypotension 141
Spinal Anesthesia (Subarachnoid block, Intrathecal block)
Comparison with epidural table 17.3 (page 178)
Complications 169
Hypotension 169
Meningitis 172
Post-spinal headache 171
Contraindications 177
Factors affecting the duration of block 169
Factors affecting the level of block 168
Indications 167
Level required for common surgeries 179
Procedure 167
Site of action of local anesthetics 167
Systemic effects 166
Spinal anesthesia in children 173
Spinal cord
Anatomy 165
Transection 197
Spinal needles 168
Spine surgery, anesthetic management 228, 264
Spirometry 10
Stages of anesthesia 88, table 9.1 (page 88)
Static current 43, 147
Stellate ganglion block 273
Stents (cardiac) and anesthetic considerations 183, 184
Stereotatic brain surgery, anesthetic considerations 228
Sterilization of anesthesia equipment 43
Steroids
For adrenalectomy 209
Preoperative 49
Stroke, anesthetic management 196, 227
Subcutaneous route for fluid administration 75
Succinylcholine (see Suxamethonium) 133
Sufentanil 117
Sugammadex 132
Superior hypogastric block 274
Supraclavicular approach for brachial plexus block 160
Supraglottic airway devices 35
Combitube 37
Laryngeal mask airway 35
Peripharyngeal airway 37, figure 3.16 (page 37)
Supreme LMA 36, figure 3.13 (page 36)
Suxamethonium
Contraindications 125
Mechanism of action 124
Metabolism 124
Pharmacokinetics 124
Prolonged block 127
Systemic effects 125
Uses 124
Synera 152
Synthetic oxygen carriers (artificial blood) 79
Syringomyelia 197
Systemic lupus erythematosus (SLE) anesthetic considerations 214
T
Tachycardia 140
Temperature
Critical 11
Monitoring 65
Indications 66
Sites 66
Teratogenicity with inhalational agents 94
Tetralogy of Fallot, anesthetic considerations 187
Thalassemia, anesthetic management 217
Thermal perturbations after GA 143
Thiopentone
Anesthetic properties 106
Complications 107
Intra-arterial injection 108
Contraindications 108
Pharmacokinetics 106
Physical properties 106
Systemic effects 107
Thoracotomy
Operative criteria 195
Pain management 193
Thrombocytopenia, anesthetic considerations 217
Thyroid dysfunctions 207
Thyromental distance 53
Tonsillar abscess 256
Tonsillectomy, anesthetic management 256
Topical
Analgesia 157
Preoperative medications 50
Total intravenous anesthesia (TIVA) 268
Tourniquet and related problems 262
Trachea
Anatomy 4
Tracheal Tug 8
Tracheoesophageal fistula (TOF), anesthetic management 240
Tracheostomy
Care 42
Complications 41
Indications 41
Tubes 41
Train of four 67, figure 6.3 (page 67)
Tramadol 117
Transesophageal echocardiography (TEE) 60
Transfusion reactions 77
Allergic 78
Febrile 78
Hemolytic 77
Transthoracic impedance pulmonometry 64
Transurethral resection of prostate (TURP)
Anesthetic management 203
Syndrome 203
Trauma
Anesthetic management 258
Trendelenburg position 146
For spinal hypotension 170
Trichloroethylene (Trielene) 102
Trigeminal nerve block 273
Trigeminal neuralgia 272
Triple H therapy for stroke 228
Tuberculosis, anesthetic considerations 194
Tubocurare 128
Tumescent anesthesia 158
Tuohy needle 174, figure 17.2 (Page 174)
Turbulent flow 11
Tympanoplasties 95
U
Universal F, single limb closed circuit 29
Uteroplacental circulation and Anesthetic drugs 231
V
Valvular diseases 185
Vaporizers 21, figure 2.12 (page 21)
Safety features 22
Sequence 22
Vasodilators for controlled hypotension 141
Vasopressors
For shock management 287
For spinal hypotension 170
Vecuronium 128
Venous air embolism (VAE) 226
Ventilation (see mechanical ventilation)
Ventilators
Anesthesia machine 22
Classification 278
Initial settings 279
Ventricular fibrillation 301
Venturi
Mask 42
Principle 11
Viagra (preoperative) 50
Video laryngoscope 34, figure 3.8 (page 34)
Vital capacity 10
Reduction in different positions 146
W
Waters circuit 24, figure 2.14 (page 24), table 2.4 (page 26)
Weaning from ventilator 283
Wooden chest syndrome 116
Wrist block 161
X
Xenon 96
Advantages over nitrous oxide 96
Xylocaine 155
Xylocard 156
Y
Yellow ligament 164
Yoke assembly 18, figure 2.7 (page 18)
×
Chapter Notes

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1Fundamental Concepts2

Applied Anatomy, Physiology and PhysicsCHAPTER 1

 
 
RESPIRATORY PHYSIOLOGY
 
Anatomy of Airways
 
Larynx (Fig. 1.1)
It is the organ of voice extending from root of tongue to trachea and lies opposite C3 to C6.
Distance between teeth and vocal cords is 12–15 cm and distance between vocal cords and carina is 10–15 cm.
It consists of 3 paired cartilages namely arytenoid, corniculate and cuneiform and three unpaired cartilages, namely thyroid, cricoid and epiglottis.
The glottis is the narrowest part in adults while subglottis (at the level of cricoid) is the narrowest part in children up to the age of 6 years. As subglottis is the narrowest part, the cuff of endotracheal tube can cause subglottic edema and stenosis, therefore the traditional approach had been not to use cuffed tube in children, however this approach is not followed in current day practice.
Nerve supply: All muscles of the larynx are supplied by recurrent laryngeal nerve except cricothyroid which is supplied by external branch of superior laryngeal nerve.
Sensory supply: Up to vocal cords by internal branch of superior laryngeal nerve and below vocal cords by recurrent laryngeal nerve.
Arterial supply: By laryngeal branches of superior and inferior thyroid arteries.
zoom view
Fig. 1.1: Laryngoscopic view of larynx
4  
Paralysis of Nerves of Larynx
  • Paralysis of recurrent laryngeal nerve of one side has no serious consequences as it is compensated by other side. There is only hoarseness of voice.
  • In bilateral partial paralysis of recurrent laryngeal nerve, the abductors (posterior cricoarytenoids) will go first (Semon's Law) causing the cords to be held in adduction producing respiratory stridor.
  • In complete paralysis of recurrent laryngeal nerve, the cords are still held in adducted position due to tensing action of cricothyroid which is supplied by superior laryngeal nerve, causing severe respiratory distress, stridor, aphonia and complete obstruction. A tracheostomy is usually required for the management.
  • In complete paralysis of both recurrent and superior laryngeal nerves, the cords are held in mid-position (cadaveric position).
  • Cords are also in cadaveric position during anesthesia with muscle relaxants.
 
Trachea
  • Length of the trachea is 10–12 cm.
  • It starts from cricoid ring (C6) and ends at carina (T5). Anteriorly carina corresponds to second costal cartilage at the junction of manubrium with sternal body (angle of Louis).
  • It consists of 16–20 incomplete rings.
  • The diameter of trachea is 1.2 cm.
 
Bronchial Tree (Fig. 1.2)
At carina trachea divides into right and left main bronchus. Distance of carina from upper incisors is 28–30 cm.
Further right main bronchus divides into right upper, middle and lower lobe bronchus and left main bronchus into left upper and lower lobe bronchus.
  • Due to shorter, wider and less acute angle chances of endotracheal tube to be positioned on right side (endobronchial intubation) are more (Table 1.1).
  • In children the angle of both right and left bronchus is same, i.e. 55° up to the age of 3 years.
Right upper lobe bronchus divides into apical, posterior and anterior segment bronchi.
Right middle lobe bronchus divides into lateral and medial segment bronchi.
Right lower lobe bronchus divides into apical, medial basal, anterior basal, lateral basal and posterior basal segment bronchi.
Left upper lobe bronchus divides into apical, anterior and posterior segment bronchi. Left upper lobe bronchus also gives rise to lingular bronchus, which is further subdivided into superior and inferior segment bronchi.
Left lower lobe bronchus divides into apical, anterior basal, posterior basal and lateral basal segment bronchi.
Segmental bronchi along with lung parenchyma constitutes bronchopulmonary segments which are 10 in number on right side, viz.
Upper lobe: Apical, posterior and anterior.
Middle lobe: Lateral and medial.
Lower lobe: Apical (superior), medial basal (cardiac), anterior basal, lateral basal and posterior basal.
On the left side bronchopulmonary segments are 9 in number, viz.
Upper lobe: Apical, posterior and anterior.
Lingular lobe: Superior lingular and inferior lingular.
Lower lobe: Apical, inferior basal, lateral basal and posterior basal.
These segmental bronchi further divide and re-divide till terminal bronchioles. Further these terminal bronchioles lose their cartilage to form respiratory bronchiole which with alveolar duct and alveolar sac forms the respiratory unit. It is at this alveolar capillary membrane where gaseous exchange takes place. The thickness of alveolar capillary membrane is 0.3 mm.
Total number of alveoli is 300 million with surface area of 70 m2.
Alveolar epithelium has type I and type II cells. Type II cells secrete surfactant.
 
FOREIGN BODY ASPIRATION
Due to shorter, wider and less acute angle of right bronchus foreign body aspiration is more common on right side.
  • In supine position most commonly involved segment is apical segment of right lower lobe.5
    zoom view
    Fig. 1.2: Bronchial tree
    1. Right main bronchus
    2. Right upper lobe bronchus
    3. Right middle lobe bronchus
    4. Right lower lobe bronchus
    5. Apical segment bronchus
    6. Posterior segment bronchus
    7. Anterior segment bronchus
    8. Lateral segment bronchus
    9. Medial segment bronchus
    10. Apical segment bronchus
    11. Medial basal bronchus
    12. Anterior basal bronchus
    13. Lateral basal bronchus
    14. Posterior basal bronchus
    1. Left main bronchus
    2. Left upper lobe bronchus
    3. Left lower lobe bronchus
    4. Apical upper lobe bronchus
    5. Posterior upper lobe bronchus
    6. Anterior upper lobe bronchus
    7. Superior bronchus
    8. Inferior bronchus
    9. Apical bronchus
    10. Anterior basal bronchus
    11. Lateral basal bronchus
    12. Posterior basal bronchus
    Table 1.1   Comparison of the anatomy of the right and left bronchus
    Right bronchus
    Left bronchus
    Shorter (length 2.5 cm)
    Longer (length 5 cm)
    Wider
    Narrower
    The angle with vertical is 25°
    The angle is 45°
    Aorta arches over the left main bronchus
  • In lateral position, most commonly involved segment is posterior segment of upper lobe (right upper lobe in right lateral and left upper lobe in left lateral).
  • In standing/sitting aspiration, most commonly aspiration occurs in posterior basal segment of right lower lobe.
Mucosa: Ciliated epithelium up to terminal bronchioles after which non-ciliated epithelium.
Ciliary activity is inhibited by all inhalational agents except ether.
Arterial supply: Bronchial artery up to terminal bronchioles and beyond terminal bronchioles by pulmonary artery.6
Nerve supply: Parasympathetic by vagus (causes bronchoconstriction).
Sympathetic by T2 to T5 (causes broncho-dilatation).
 
REGULATION OF RESPIRATION
Mediated by:
  • Pneumotaxic center in upper pons.
  • Apneustic center in lower pons.
  • Ventral group of neurons in medulla (expiratory group).
  • Dorsal group of neurons in medulla (inspiratory group).
Normally pneumotaxic center has inhibitory effect on apneustic center which otherwise produces apneustic breathing or inspiratory spasm.
Normal respiration is maintained by expiratory and inspiratory neurons of medulla.
During inspiration stretch receptors in lung parenchyma, which are supplied by vagus get stimulated leading to inhibition of inspiratory group of neurons, and hence stopping the inspiration.
Expiration is normally passive and expiratory group of neurons comes into play only during active expiration.
These central respiratory centers are most sensitive to changes in CSF pH, which in turn is influenced by pCO2 (partial pressure of carbon dioxide in blood).
Increase in pCO2 stimulates the respiration while decrease in pCO2 inhibits respiration. Other factors effecting respiratory centers are:
  • Body temperature
  • Hypoxia
  • Exercise
  • Pain
  • Hypothalamus
  • Cortex.
Peripheral chemoreceptors: These are present in carotid body and aortic arch. Carotid body receptors are very sensitive to hypoxia.
All inhalational agents (except nitrous oxide and minimum with ether) have depressant effect on ventilatory response to increased CO2 and hypoxia.
 
MUSCLES OF RESPIRATION
 
Inspiration
Diaphragm is the most important muscle of inspiration (moves 1.5 cm in quiet respiration and 6–10 cm in deep breathing).
External intercostals, pectoralis minor and scalene also assist in normal inspiration.
Pectoralis major, latissimus dorsi and sternomastoids are needed during deep inspiration.
Respiration in males is abdominothoracic while in children and females, it is thoracoabdominal.
 
Expiration
Expiration is normally passive. Forced expiration is mediated by internal intercostals and abdominal muscles.
During anesthesia with inhalational agents expiration is active, mediated by abdominal muscles.
 
AIRWAY RESISTANCE
For air to flow in lungs a pressure gradient must develop to overcome the airway resistance. This pressure gradient depends on airway caliber and pattern of airflow.
At laminar flows (which occurs below the main bronchi where velocity is less), resistance is proportional to flow rates but at turbulent flow (seen in trachea and main bronchi) resistance is square of flow rates. In other words, it can be said that maximum airway resistance to airflow occurs in trachea and then main bronchus and minimum in terminal bronchi.
 
VENTILATION/PERFUSION (V/Q)
Both ventilation and perfusion is more at bases as compared to apex but perfusion at base is comparatively higher decreasing V/Q ratio towards base (from 2.1 at apex to 0.3 at base, average 0.8).
This ventilation perfusion mismatch is responsible for producing alveolar dead space (i.e. alveoli are only ventilated but not perfused, wasting the oxygen in alveoli).
This V/Q mismatch creates alveolar to arterial oxygen difference [(A–a) pO2 difference] which is normally 3–5 mm Hg.
This A-a difference is increased in lung pathologies affecting alveoli such as pulmonary edema, acute respiratory distress syndrome (ARDS) and interstitial lung disease.7
 
DEAD SPACE
Total dead space (also called as physiological dead space) = Anatomical dead space + Alveolar dead space.
 
Anatomical Dead Space
It is constituted by air which is not participating in diffusion. Therefore it is constituted by air present in nose, trachea and bronchial tree (up to terminal bronchioles). Normally, it is 30% of tidal volume or 2 mL/kg or 150 mL.
Anatomical dead space is increased in:
  • Old age
  • Neck extension
  • Jaw protrusion
  • Bronchodilators
  • Increasing lung volume
  • Atropine (causes bronchodilatation)
  • Anesthesia mask, circuits
  • Intermittent positive pressure ventilation (IPPV) and positive end-expiratory pressure (PEEP).
Anatomical dead space is decreased by:
  • Intubation (nasal cavity is bypassed and diameter of tube is less than airway diameter)
  • Tracheostomy (upper airways and nasal cavity bypassed)
  • Hyperventilation (decreasing lung volume)
  • Neck flexion
  • Bronchoconstrictors.
 
Alveolar Dead Space
It is constituted by alveoli which are only ventilated but not perfused. It is 60–80 mL in standing position and zero in lying position (in lying position perfusion is equal in all parts of lung).
It is increased by:
  • Lung pathologies affecting diffusion at alveolar capillary membrane such as interstitial lung disease, pulmonary embolism, pulmonary edema and ARDS.
  • General anesthesia.
  • IPPV.
  • PEEP.
  • Hypotension.
 
Anesthesia and Dead Space
  • All anesthesia circuits, masks, humidifiers increase the anatomical dead space.
  • Endotracheal tubes, tracheostomy decreases the anatomical dead space by bypassing the upper airways.
  • All inhalational agents increase both anatomical and alveolar dead space. Anatomical dead space is increased because all these agents are bronchodilators. Alveolar dead space is increased because of hypotension (decreased perfusion) produced by these agents.
  • Positions during anesthesia, especially lateral position causes more ventilation in upper lung (non-dependent) and more blood flow in lower lung (dependent lung), thereby increasing the V/Q mismatch, and hence alveolar dead space. Other positions such as Trendelenburg, lithotomy also causes the V/Q mismatch.
  • Anesthesia ventilation techniques such as IPPV, PEEP increase both anatomical and alveolar dead space. Anatomical dead space is increased by increasing lung volume and alveolar dead space is increased because of hypotension produced by IPPV and PEEP (Increase in intrathoracic pressure produced by IPPV/PEEP decreases the venous return, cardiac output and hence hypotension).
 
OXYGEN AND CARBON DIOXIDE IN BLOOD
 
Oxygen
Normal oxygen uptake is 250 mL/min.
Oxygen is mainly carried in blood attached to hemoglobin (1 g of Hb carries 1.34 mL of oxygen). Very less amount, 0.003 mL/dL/mm Hg is carried as dissolved fraction. Oxygen content of arterial blood is 20 mL/dL and that of venous blood is 15 mL/dL.
 
Oxygen Dissociation Curve (Fig. 1.3)
Normally, Hb is 97% saturated at normal partial pressure (pO2) of oxygen, which is 95–98 mm Hg.
At 60 mm Hg, saturation is still 90%. After this point, there is sudden drop in oxygen saturation leading to significant desaturation of Hb (cyanosis appears when pO2 fall below 50–60 mm Hg).8
P50 is the partial pressure at which oxygen saturation is 50%. The partial pressure of oxygen for 50% saturation is 26 mm Hg. P50 is not effected by anesthetics.
Bohr effect: Alkalosis shifts O2 dissociation curve to left and acidosis to right.
Oxygen flux: It is the amount of oxygen leaving left ventricle/minute.
It is 1,000 mL/min.
Shift of oxygen dissociation curve is seen with:
To left
To right
Alkalosis
Acidosis
Low pCO2
High pCO2
Decreased 2,3 DPG
Increased 2,3 DPG
Carbon monoxide poisoning
Hyperthermia
Abnormal hemoglobins like methemoglobin, fetal hemoglobin, etc.
Inhalational anesthetics
Hypophosphatemia
Hypothermia
 
Carbon Dioxide
Transported in blood as:
  • Bicarbonate (90%).
  • Dissolved (0.0308 mmol/L/mm Hg): 5% of total.
  • As carbamino compounds.
 
CO2 Dissociation Curve (Fig. 1.4)
It is relationship between pCO2 and CO2 content.
Deoxygenated blood has more CO2 content at a given pCO2, this is called as Haldane effect.
 
ABNORMALITIES OF CHEST MOVEMENTS
 
Paradoxical Respiration
Seen in flail chest.
Treatment: IPPV.
 
Tracheal Tug
This is downward movement of trachea during deep inspiration. It is seen in:
  • Deep anesthesia (by inhalational agents).
  • Partially curarized patient.
  • Upper airway obstruction (this is the main reason of tracheal tug at the end of anesthesia as airway can get obstructed by secretions).
zoom view
Fig. 1.3: Oxygen dissociation curve
zoom view
Fig. 1.4: CO2 dissociation curve
Mechanism: During deep anesthesia and partially curarized patient diaphragm is not supported by costal margins. Also larynx is not supported by neck muscles so strong contraction of central part of diaphragm pulls the trachea downwards.
 
Sigh
It is deep inspiratory hold.
 
Hiccup
Intermittent clonic spasm of diaphragm of reflex origin.9
 
Causes
  • Light anesthesia.
  • Gastric and bowel distension.
  • Diaphragm irritation by touching diaphragm in upper abdominal surgeries.
  • Uremia.
 
Treatment
  • Increase the depth of anesthesia.
  • Muscle relaxants.
  • Pharyngeal stimulation by nasal catheter, Valsalva maneuver, CO2 inhalation.
  • Drugs such as amyl nitrate.
  • Ether.
  • For intractable hiccups, phrenic nerve block may be required.
 
HYPOXIC PULMONARY VASOCONSTRICTION
This is a protective mechanism. Whenever there is hypoxia, there occurs vasoconstriction in these hypoxic areas leading to shunting of blood to well-perfused area, decreasing the V/Q mismatch. All inhalational agents blunt this hypoxic pulmonary vasoconstriction (HPV) response thereby increasing the shunt fraction (maximum with halothane).
 
PULMONARY FUNCTION TESTS
 
Lung Volumes (Fig. 1.5)
Tidal volume: Volume of gas inspired or expired in each breath during normal quiet respiration.
It is 400–500 mL (10 mL/kg).
Inspiratory reserve volume: It is the maximum volume of gas which a person can inhale from end inspiratory position.
It is 2400–2600 mL.
Inspiratory capacity: It is the maximum volume which can be inhaled from end expiratory position i.e. it is inspiratory reserve volume + tidal volume.
It is 2500 (IRV) + 500 (TV) = 3,000 mL
Expiratory reserve volume: Maximum volume of gas that can be exhaled after normal expiration.
It is 1200–1500 mL.
Vital capacity: It is the maximum amount of gas that can be exhaled after maximum inhalation, i.e. it is IRV + TV + ERV.
It is 4200–4500 mL (75–80 mL/kg).
zoom view
Fig. 1.5: Lung volumes
  • TV = Tidal volume
  • IRV = Inspiratory reserve volume
  • IC = Inspiratory capacity
  • ERV = Expiratory reserve volume
  • RV = Residual volume
  • FRC = Functional residual capacity
  • VC = Vital capacity
  • TLC = Total lung capacity
  • All these lung volumes are approximately 5% less in females (except residual volume).
Residual volume: It is volume of gas still present in lungs after maximal expiration.
It is 1200–1500 mL.
Maximum breathing capacity: Maximum volume of air that can be breathed/minute. It is 120–170 L/min (normally it is measured for 15 seconds and expressed as L/min).
Minute volume: It is tidal volume × respiratory rate.
It is 500 × 12 = 6000 mL/min.
Total lung volume: IRV + TV + ERV + RV.
It is 5500–6000 mL.
Functional residual capacity (FRC): It is the volume of gas in lungs after end expiration. It is ERV + RV. It is 2400–2600 mL.
During general anesthesia FRC decreases by 15–20%.
 
Simple Bedside Test
  • Breath-holding time: It is very simple and useful bedside test. Normal is > 25 seconds. Patients with breath-holding time of 15–25 seconds are considered borderline cases and breath holding time < 15 seconds indicate severe pulmonary dysfunction.
  • Match test: Person is asked to blow-off match stick from a distance of 15 cm. A person with normal pulmonary reserve will blow off the match-stick from this distance.10
  • Tracheal auscultation: If breath sounds are audible for more than 6 seconds it denotes significant airway obstruction.
  • Able to blow a balloon.
  • Spirometry by pocket size microspirometers can now be performed on bed side.
 
Spirometry
It is the instrument used to measure following lung volumes:
  • Tidal volume
  • Inspiratory reserve volume
  • Inspiratory capacity
  • Expiratory reserve volume
  • Vital capacity.
It cannot measure residual volume, therefore any lung volume which requires measurement of residual volume, i.e. functional residual capacity and total lung volume cannot be measured by spirometry.
 
Forced Spirometry (Timed Expiratory Spirogram)
Forced vital capacity (FVC): Expiration is performed as hard as possible. It is 4200–4500 mL (75–80 mL/kg)
Forced expiratory volume (FeV): It is the volume of gas expired in 1 second (FeV1), 2 seconds (FeV2), 3 seconds (FeV3) measured from the start of expiration after full inspiration (forced vital capacity). Normal person can exhale 83–85% of FVC in 1 second (so FeV1 is 83–85%), 93% in 2 seconds (FeV2 is 93%) and 97% in 3 seconds (FeV3 is 97%).
FeV1/FVC ratio is important as this ratio is decreased in obstructive lung diseases. It is expressed as percentage.
Peak expiratory flow rate: Normal 500–600 L/min.
Forced mid-expiratory flow rate: Measures flow rate during 25–75% of exhalation.
 
Flow Volume Loops
These are more sensitive and informative in detecting pulmonary diseases than conventional spirometry. Modern microprocessor controlled recording spirometers automatically generate these flow volume loops.
 
Body Plethysmography, Helium Dilution, Nitrogen Washout
These techniques are employed for measuring functional residual capacity, residual volume and total lung capacity.
Helium dilution technique is also used to measure closing capacity, which is the volume at which airway closes. Normally it is 1 litre less than functional residual capacity. If functional residual capacity falls below closing capacity there will be significant hypoventilation and V/Q abnormalities.
Body plethysmograph is also used to measure airway resistance (normal = 2.5 cm H2O/L/second).
 
Lung Compliance
It is volume change per unit of pressure.
Lung compliance
:
0.2 L/cm H2O
Chest wall compliance
:
0.2 L/cm H2O
Total compliance
:
0.1 L/cm H2O (lung and chest wall compliance act in opposite direction).
 
Blood Gas Analysis
Described in Chapter 40, page no. 293.
 
Pleural Pressures
Normal intrapleural pressure is −3 to −5 cm H2O.
During inspiration, it becomes more negative up to −7 cm H2O.
During expiration, it is +1 to +2 cm H2O.
 
Fitness for Surgery and Pulmonary Functions
  • Patients with FVC < 20 mL/kg and FeV1 <15 mL/kg require appropriate preoperative preparation before surgery such as chest physiotherapy, antibiotics, bronchodilators, etc.
  • Patient with FeV1< 10 mL/kg and history of dyspnea at rest or on minimal activity should be subjected to only life-saving operations.
Three most important criteria to indicate severe respiratory compromise are:
  1. Dyspnea at rest or on minimal activity.
  2. FeV1 < 15 mL/kg (normal 65 mL/kg).
  3. pO2 < 60 mm Hg (or oxygen saturation < 90%) on room air.11
 
PHYSICS RELATED TO ANESTHESIA
 
Boyle's Law
At a constant temperature, volume of gas is inversely proportional to the pressure.
 
Charle's Law
At a constant pressure, volume of gas is directly proportional to temperature.
 
Graham's Law
The rate of diffusion of gas is inversely proportional to square root of their molecular weight.
An ideal gas should follow all the above said laws.
 
Partial Pressure of Gas
It is the pressure exerted by each gas in a gaseous mixture.
 
Vapor
Vapor is the gaseous state of liquid.
 
Avogadro Number
The number of molecules contained in one gram molecular weight of any compound. It is 6.23 × 1023.
 
Critical Temperature
It is the temperature below which a gas can be stored in liquid form.
 
Flow of Gases
Flow may be laminar or turbulent.
 
Laminar
Laminar flow is produced when the gas pass through straight tube. Flow is smooth. Laminar flow is more dependent on viscosity.
At laminar flow, Hagen–Poiseuille law is applicable which states that flow rate is directly proportional to pressure gradient and fourth power of radius of tube and inversely proportional to viscosity and length.
zoom view
Q = Flow rate
P2– P2 = Pressure gradient (P1 and P2 are pressure at each end of tube)
η = Viscosity
l = Length.
 
Turbulent
Turbulent flow is produced, if flow rate is very high or if gas passes through bends, constrictions. Flow is rough. Reynolds number must exceed to 2,000 for turbulence. Turbulent flow is more dependent on density.
 
VENTURI PRINCIPLE
When a fluid or gas passes through a tube of varying diameter, the pressure exerted by fluid (lateral pressure) is minimum where velocity is maximum (pressure energy drops where kinetic energy increases: Bernoulli's law).
This principle is very much utilized in anesthesia particularly with Venturi masks. By increasing flow rate (velocity) through narrow constriction sub atmospheric pressure can be created in vicinity enthralling air to mix in fixed proportion (through pores in mask) with oxygen. Jet ventilation and suction apparatus also works on this principle.
 
POYNTING EFFECT
Mixing of liquid nitrous oxide at low pressure with oxygen at high pressure (in Entonox) leads to formation of gas of nitrous oxide. Therefore, oxygen and nitrous oxide both are present in gaseous state in Entonox cylinder.