Preoperative Evaluation and Preparation ผศ.พญ.น าท พย ไตรยส น นท ภาคว ชาว ส ญญ ว ทยา คณะแพทยศาสตร ศ ร ราชพยาบาล มหาว ทยาล ยมห ดล

Transcription

1 Preoperative Evaluation and Preparation ผศ.พญ.น าท พย ไตรยส น นท ภาคว ชาว ส ญญ ว ทยา คณะแพทยศาสตร ศ ร ราชพยาบาล มหาว ทยาล ยมห ดล

2 Outline Goals of preoperative assessment Preoperative evaluation - Hx taking, physical examination, investigations - Airway assessment - ASA classification Preoperative preparation Premedication Management of common diseases (HT, DM, COPD/asthma) 2

3 Goals of preoperative assessment Assess medical conditions Manage and improve comorbidities Risk assessment Plan for anesthetic technique and special care Patient education and motivation for preventive care (e.g. stop smoking) Obtain informed consent Doctor-patient relationship 3

4 Preoperative evaluation Patient evaluation - History taking and medical record - Physical examination - Investigations Risk assessment - American Society of Anesthesiologists (ASA) classification 4

5 Taking History Present illness and plan of procedure Medical history, physical status Current medications Previous surgical and anesthetics Allergies Smoking, alcohol, drugs Family history Review of system 5

6 Review of System 1) Cardiovascular - HT, CAD, VHD, arrhythmia, CHF 2) Respiratory - Asthma, COPD, URI, pneumonia, smoking 3) CNS - Seizure, CVA, neuropathy, psychiatric diseases 4) Endocrine - DM, thyroid disease, steroids 5) Renal - CKD, UTI, dialysis 6

7 6) Hematologic Review of System - Anemia, abnormal bleeding, chronic blood loss, blood transfusion 7) Gastrointestinal - Jaundice, hepatitis, peptic ulcer, GERD, vomiting, bleeding 8) Musculoskeletal - Myopathy, arthritis, scoliosis, spinal surgery 9) Others - Pregnancy, chemo/radiation therapy 7

8 Anesthetic History Previous operations/procedures Anesthetic technique; GA, RA, PNB Complications - Difficult airways - Unexpected ICU admission - PONV - CVS events; MI, pulmonary edema - Others; delay emergent, neuropathy 8

9 Physical Examination Vital signs, oxygen saturation Body weight, height, BMI Review of system Airway assessment * Focus on history related problems* 9

10 Airway assessment General appearance, BW, facial hair, deformities Oral cavity, teeth, denture, palate, tongue, mass Neck ; thickness, ROM, mass, thyroid gland Distance - Inter incisor > 3 cm - Thyromental > 6 cm - Sternomental > 12 cm Mallampati classification 10

11 Mallampati classification Tonsillar pillars Uvula Fauces Soft palate Uvula Fauces Soft palate Soft palate Hard palate 11

12 Difficult airway 12

13 Based on Investigations - Clinical information; positive finding from Hx,PE - Comorbid conditions, underlying disease - Surgical type (major Sx, massive blood loss, large fluid shift) NO routine investigations 13

14 Test CBC Urinalysis Electrolytes BUN/Cr Blood sugar LFTs Coagulogram CXR ECG Indications Anemia, abnornal bleeding, renal disease All patients (screening test) Renal disease, DM, dehydration, diuretics Renal disease, HT, DM, dehydration Diabetes, steroids Hepatic disease, alcoholism, malnutrition Bleeding, hepatic disease, anticoagulates Cardiac/pulmonary disease, risk of pulm TB Cardiac disease, HT, DM, arrhythmia 14

15 Investigations Screening test for age > 60 year old - CBC, BUN/Cr, Blood sugar, CXR, ECG Major surgery/ massive blood loss - CBC, BUN/Cr, electrolytes, coagulogram 15

16 Investigations A-65-year-old male presents for total knee arthroplasty. He has hypertension and diabetes. He has been on HCTZ 25 mg, glibenclamide and metformin CBC U/A BUN/ Cr Elytes LFTs BS Coag CXR ECG 16

17 ASA classification ASA Class Disease state Healthy patient without medical problems Mild to moderate systemic disease (well-controlled) Severe systemic disturbance Severe systemic disturbance (life threatening) Moribund who is not expected to survive 24 hrs with or without operation Brain-dead patient (organ donor) * E added to indicate emergency operation 17

18 Peri-operative mortality rate ASA class Mortality rate (%)

19 Preoperative preparation Patient and families education Patient preparation - Psychological support - Optimize condition, consult specialists - NPO - Premedication Management of comorbid conditions e.g. DM, HT, IHD, COPD, asthma, ESRD ICU booking/cross matching 19

20 NPO times - ASA fasting guidelines Ingested material Clear liquid Breast milk Non-human milk Light meal Heavy meal Minimum fast (hr)

21 Premedication Anxiolytic and sedation Amnesia Pre-emptive analgesia Hemodynamic stability Decrease risk of aspiration Decrease anesthetic requirements Facilitate induction of anesthesia 21

22 Premedication Benzodiazepines; diazepam, midazolam Analgesic drugs; opioids, NSAIDs, paracetamol Prokinetic; metoclopramide Antiemetic; ondansetron Antacids; H 2 blocker, PPI Cardiovascular medications; anti HT, β blocker Steroids supplementary 22

23 Benzodiazepines Drug Oral prep Oral dose Peak effect (oral dose) Diazepam Tab 2,5 mg 2-10 mg hr Lorazepam Tab 0.5,1,2 mg mg 2-4 hr Midazolam Tab 15 mg 5-10 mg hr 23

24 Side effects - Respiratory depression - Over sedation /confusion - Hypotension Caution of using with - Elderly - Pediatric patient Benzodiazepines - High risk of airway obstruction or aspiration; OSA, obesity - Pregnancy 24

25 Pre-emptive analgesia Reduce sensitization of the peripheral and central pain pathways Protective effect on the nociceptive system Reduce intraoperative analgesic drugs requirement Reduce postoperative pain Modalities - Opioids; oral, IM, IV - NSAIDs; oral, IM, IV - NMDA receptor antagonist; ketamine - Neuraxial block/ peripheral nerve block 25

26 Prevent aspiration Reduce gastric volume/increase gastric ph - H 2 receptor antagonist ; cimetidine, ranitidine - PPI; omeprazole Increase gastric ph - Non particulate antacid; 0.3 M sodium citrate Increase gastric motility/ge sphincter tone - Metoclopramide (plasil) 26

27 Prevent aspiration High risk patients - Full stomach; emergency case - Obesity - Pregnancy - DM/ Renal failure - Gut obstruction - GERD - Trauma 27

28 Management of common diseases 1) Hypertension 2) Diabetes 3) Asthma/ COPD 28

29 Cause, duration, severity Current medications Hypertension Target organ damage (CVS, renal, neuro) Delay or cancel an elective case in poorly controlled or untreated hypertension (SBP > 220 or DBP > 110 mmhg) Continue β blockers, calcium channel blockers, clonidine Diuretics can cause electrolyte imbalance ACEIs and ARBs can cause postinduction hypotension 29

30 Diabetes Type I or II (Insulin deficiency or resistance) Onset/duration of disease Glucose control Treatment; oral hypoglycemic, insulin Complications - Hypoglycemic episode - DKA or hyperosmolar coma Systemic involvements 30

31 Diabetes Organ system Cardiovascular Neurologic Gastrointestinal Renal Airway Evaluation Myocardial ischemia, orthostatic hypotension, peripheral vascular diseases Stroke, neuropathy, autonomic dysfunction Gastroparesis, GE reflux Nephropathy, volume status, osmotic dieresis Joint stiffness, neck mobility, TM joint 31

32 Diabetes Patient should be scheduled as the first case of the day Determined pre, intra and postoperative BS Discontinue all rapid and short acting insulin Discontinue oral hypoglycemic agents Take 1/3 to 1/2 of usual morning dose of long acting insulin (NPH or premixed) Preop BS control; RI add in 5% Dextrose 32

33 Asthma/COPD Duration, severity, exacerbation, treatment Further Ix in severe cases; PFT, arterial blood gas Encourage cessation of smoking at least 6-8 wks Administer antibiotic and delay surgery if respiratory infection is present Continue bronchodilators (inhaled, oral, IV) Steroid supplement if taking prednisolone > 10 mg/d Educated deep breathing exercise Chest physiotherapy 33

34 Question??? 34