pre- and post-operative monitoring of patients

Pre-operative Preparation Pre-operative Preparation and and

Peri-, Post-operative Peri-, Post-operative Monitoring Monitoring

of the of the Surgical PatientSurgical Patient

Alfred D. Troncales, MD, DPBSAlfred D. Troncales, MD, DPBSPamantasan ng Lungsod ng Pamantasan ng Lungsod ng

MaynilaMaynilaCollege of MedicineCollege of Medicine

SURGERYSURGERY

“ “ One of the most challenging aspect One of the most challenging aspect of surgical practice is not just of surgical practice is not just making the decision to perform a making the decision to perform a surgical procedure on a patient, but surgical procedure on a patient, but deciding on deciding on the proper timingthe proper timing when a surgical procedure can be when a surgical procedure can be done.” done.”

Surgical Management Surgical Management DecisionDecision

Surgery

Management

Disease

Patient

SURGERYSURGERY Disease Factor:Disease Factor:

Natural HistoryNatural History PrognosisPrognosis

Management Factor:Management Factor: Classical and Advances in Surgical and Medical Classical and Advances in Surgical and Medical

Techniques (Management Options)Techniques (Management Options) Anesthesia Methods and MedicationsAnesthesia Methods and Medications

Patient Factor:Patient Factor: General Health (Optimization)General Health (Optimization) Co-morbid Conditions (Identify and Manage)Co-morbid Conditions (Identify and Manage) Psychological PreparationPsychological Preparation

SURGERYSURGERY

“ “ Thus, appropriate Thus, appropriate pre-operative pre-operative preparationpreparation andand post-operative post-operative monitoringmonitoring is absolutely mandatory is absolutely mandatory and essential to minimize the risks, and essential to minimize the risks, lessen complications and optimize lessen complications and optimize outcome of a patient even with the outcome of a patient even with the best technically performed operative best technically performed operative procedure.” procedure.”

Pre-operative CarePre-operative Care

Optimize efficiency and bed utilization preoperatively

Avoid delays and cancellations resulting in lost operating room time

Proactively coordinate patient care with other specialties

Provide high-quality and safe patient care

Improve patient satisfaction and set foundation for optimum outcomes

OBJECTIVES

General Aspects of Pre-General Aspects of Pre-op Careop Care

History and Physical ExaminationHistory and Physical Examination

Surgical ConsentSurgical Consent

Patient Preparation:Patient Preparation: Psychological preparationPsychological preparation Physical preparationPhysical preparation Physiological preparationPhysiological preparation

History and Physical History and Physical ExaminationExamination

Diagnosis of current conditionDiagnosis of current condition Identifies associated risk factors:Identifies associated risk factors:

Age of the patient (Extremes of age)Age of the patient (Extremes of age) Co-morbid conditionsCo-morbid conditions Previous surgeryPrevious surgery

Determines current medicationsDetermines current medications Reviews past medical historyReviews past medical history Determines physical status:Determines physical status:

American Society of Anesthesiologists’ (ASA) American Society of Anesthesiologists’ (ASA) Physical Status Assessment Physical Status Assessment

Pre-operative Medical Pre-operative Medical CareCare

Elective/EmergencyElective/Emergency Cardiac diseaseCardiac disease Pulmonary diseasePulmonary disease Renal dysfunctionRenal dysfunction Liver dysfunctionLiver dysfunction DiabeticsDiabetics Bleeding disordersBleeding disorders MalnourishedMalnourished

Surgical EmergencySurgical Emergency

AMPLEAMPLE History:History: A A llergiesllergies M M edications edications P P ast Medical Historyast Medical History L L last meallast meal E E vents Preceding Surgeryvents Preceding Surgery

Pre-operative Medical Pre-operative Medical CareCare

Elective/EmergencyElective/Emergency Cardiac diseaseCardiac disease Pulmonary diseasePulmonary disease Renal dysfunctionRenal dysfunction Liver dysfunctionLiver dysfunction DiabeticsDiabetics Bleeding disordersBleeding disorders MalnourishedMalnourished

Coronary Artery Coronary Artery DiseaseDisease

Definition of CAD....Definition of CAD....

Physiology of SurgeryPhysiology of Surgery:: myocardial oxygen demandmyocardial oxygen demand catecholamines: catecholamines: HR, HR, contractility, contractility, PVRPVR HR also causes decreased diastolic fillingHR also causes decreased diastolic filling

Coronary arteries fill in diastoleCoronary arteries fill in diastole Less blood flowing in coronaries: less myocardial Less blood flowing in coronaries: less myocardial

OO22 supply supply

Myocardial InfarctionMyocardial Infarction Pt without risks: Pt without risks: 0.5% chance of MI0.5% chance of MI Pt with risks:Pt with risks: 5% chance of perioperative MI5% chance of perioperative MI Perioperative MI has 17-41% mortalityPerioperative MI has 17-41% mortality CAD causes MICAD causes MI Risk stratifications:Risk stratifications:

MI w/in 3 months of MI w/in 3 months of OROR

27% reinfarction rate27% reinfarction rate

MI 3-6 months before MI 3-6 months before OROR

10% reinfarction rate10% reinfarction rate

MI >6 months of ORMI >6 months of OR 5-8% reinfarction 5-8% reinfarction rate*rate*

Criteria: Points

A. Historical: Age >70 yr. 5 Myocardial infarction previous 6 months 10

B. Examination: S3 gallop or jugular venous distention 11 Significant aortic valvular stenosis 3 C. Electrocardiogram: Premature atrial contractions or other rhythm 7 >5 premature ventricular contractions/min. 7

D. General status: Abnormal blood gases 3 K+/HCO3 abnormalities 3 Abnormal renal function 3 Liver disease or bedridden 3 E. Operation: Emergency 4 Intraperitoneal, intrathoracic, aortic 3 Total possible: 53

Adapted from Goldman, L., Caldera, D. L., Nussbaum, S. R., et al.: N.

Engl. J. Med., 1977; 297:845. Copyright 1977. Massachusetts Medical Society. All rights reserved.

Goldman IndexGoldman Index

Goldman Classification

Class Point Total

I 0-5

II 6-12

III 13-25

IV > 26

Goldman Cardiac Risk in Non-cardiac SurgeryClass III & IV patient warrant routine pre-operative cardiology

consultation

Class IV – life saving procedure only

28 of the 53 points are potentially correctible pre-operatively

Index correctly classified 81% of cardiac outcomes

Pre-operative Medical CarePre-operative Medical Care

Surgical emergencySurgical emergency Cardiac diseaseCardiac disease Pulmonary diseasePulmonary disease Renal dysfunctionRenal dysfunction Liver dysfunctionLiver dysfunction DiabeticsDiabetics Bleeding disordersBleeding disorders MalnourishedMalnourished

Pulmonary DiseasePulmonary Disease

Patient History:Patient History: unexplained dyspnea, cough, reduced exercise unexplained dyspnea, cough, reduced exercise

tolerance tolerance Physical Exam:Physical Exam:

wheeze, rales, rhonchi, wheeze, rales, rhonchi, exp time, exp time, BS BS 5.8x more likely to develop pulmonary 5.8x more likely to develop pulmonary

complications*complications* Pre-operative CXR:Pre-operative CXR:

Mandatory in patients over 40 yoMandatory in patients over 40 yo ABG:ABG:

no role for routine useno role for routine use result should not prohibit surgeryresult should not prohibit surgery

* Lawrence et al Chest 110:744, 1996

Pulmonary DiseasePulmonary Disease Patient-related Patient-related

risks:risks: Chronic lung dz – Chronic lung dz –

wheeze, productive wheeze, productive coughcough

SmokingSmoking General healthGeneral health ObesityObesity Age?Age?

separate from separate from others?others?

Procedure related Procedure related risks:risks: Type of anesthesiaType of anesthesia

GETA alone GETA alone FRC FRC 11%11%

inhibited coughing inhibited coughing peri-opperi-op

Surgical siteSurgical site Duration of surgeryDuration of surgery

Modifiable Pulmonary RisksModifiable Pulmonary Risks

Obesity Risks:Obesity Risks: lung capacity, FRC, lung capacity, FRC,

VCVC HypoxemiaHypoxemia

Tobacco Risks:Tobacco Risks: Definition of “stopped Definition of “stopped

smoking”....smoking”.... ““When was your last When was your last

cigarette?”cigarette?”


Surgical emergencySurgical emergency Cardiac diseaseCardiac disease Pulmonary diseasePulmonary disease Renal dysfunctionRenal dysfunction

Dialysis dependentDialysis dependent Liver dysfunctionLiver dysfunction DiabeticsDiabetics Bleeding disordersBleeding disorders MalnourishedMalnourished

Renal DysfunctionRenal Dysfunction Not all renal failure is Not all renal failure is

oliguricoliguric

Check BUN/CrCheck BUN/Cr

Assume DM have CRIAssume DM have CRI Volume statusVolume status ElectrolytesElectrolytes

Drug metabolismDrug metabolism

Renal DysfunctionRenal Dysfunction

Dialyze preop to Dialyze preop to improve electrolytes, improve electrolytes, volume statusvolume status

No or limit KNo or limit K++ in MIVF in MIVF

Very judicious MIVF Very judicious MIVF while on NPOwhile on NPO

Consider: Altered drug metabolism Altered platelet fxn


Surgical emergencySurgical emergency Cardiac diseaseCardiac disease Pulmonary diseasePulmonary disease Renal dysfunctionRenal dysfunction Liver dysfunctionLiver dysfunction DiabeticsDiabetics Bleeding disordersBleeding disorders MalnourishedMalnourished

Why does hepatic disease cause coagulopathy?

Child-Pugh Criteria for Hepatic Child-Pugh Criteria for Hepatic ReserveReserve

MeasureMeasure AA BB CC

BilirubinBilirubin <2.0<2.0 2-32-3 >3.0>3.0

AlbuminAlbumin >3.5>3.5 2.8-3.52.8-3.5 <2.8<2.8

ProthrombProthrombin Time in Time (PT) (PT) increaseincrease

1-31-3 4-64-6 >6>6

AscitesAscites NoneNone SlightSlight ModerateModerate

NeuroNeuro NoneNone MinimalMinimal ““Coma”Coma”

Child-Pugh Criteria for Child-Pugh Criteria for Hepatic ReserveHepatic Reserve

Predictor of perioperative Predictor of perioperative mortality:mortality: Class A: Class A: 0 - 5% 0 - 5% Class B: Class B: 10 – 15%10 – 15% Class C: Class C: > 25%> 25%

Correct what you can Correct what you can vitamin K, vitamin K, FFP, Albumin, etc.FFP, Albumin, etc.

Anticipate bleeding, complicationsAnticipate bleeding, complications

Townsend, Textbook of Surgery, 16th ed.

Perioperative Medical CarePerioperative Medical Care

Surgical Surgical emergencyemergency

Cardiac diseaseCardiac disease Pulmonary diseasePulmonary disease Renal dysfunctionRenal dysfunction Liver dysfunctionLiver dysfunction DiabeticsDiabetics Bleeding disordersBleeding disorders MalnourishedMalnourished

Patients with DiabetesPatients with Diabetes

Coronary Artery DiseaseCoronary Artery Disease NeuropathyNeuropathy Diabetic NephropathyDiabetic Nephropathy InfectionInfection OthersOthers Treatment:Treatment:

Control of hyperglycemia pre-Control of hyperglycemia pre-operativelyoperatively

Pre-operative Medical Care

Surgical emergencySurgical emergency Cardiac diseaseCardiac disease Pulmonary diseasePulmonary disease Renal dysfunctionRenal dysfunction Liver dysfunctionLiver dysfunction DiabeticsDiabetics Bleeding disordersBleeding disorders

IatrogenicIatrogenic InheritedInherited

MalnourishedMalnourished

Reasons patients are placed on anticoagulants:

−Atrial fibrillation

−Prosthetic heart valve

−DVT or PE

−CVA or TIA

−Hypercoagulable state

REVIEW: Merritt J Thrombosis and Thrombolysis 13(2), 97-103, 2002

Evaluation of Hemostatic Evaluation of Hemostatic DisordersDisorders

HistoryHistory:: Easy bruising, epistaxisEasy bruising, epistaxis

Cut when shavingCut when shaving Heavy menstrual bleedingHeavy menstrual bleeding

Family history of bleeding Family history of bleeding disordersdisorders

ASA / NSAID’sASA / NSAID’s Renal diseaseRenal disease Hepatic disease (EtOH)Hepatic disease (EtOH)

PhysicalPhysical:: EcchymosesEcchymoses HepatosplenomegalyHepatosplenomegaly Excessive mobility of Excessive mobility of

joints or excess skin laxityjoints or excess skin laxity Stigmata of renal or Stigmata of renal or

hepatic diseasehepatic disease

Laboratory Tests of Bleeding Laboratory Tests of Bleeding FunctionFunction

Prothrombin time (PT/INR):Prothrombin time (PT/INR): Measures factor VII and Measures factor VII and common pathwaycommon pathway

factors (factor X, prothrombin/thrombin, factors (factor X, prothrombin/thrombin, fibrinogen, and fibrin)fibrinogen, and fibrin)

Partial thromboplastin time (PTT):Partial thromboplastin time (PTT): Intrinsic pathwayIntrinsic pathway and common pathway and common pathway

Platelet count:Platelet count: quantifies plateletsquantifies platelets

Bleeding time and Clotting time:Bleeding time and Clotting time: estimates qualitative platelet functionestimates qualitative platelet function

Patients on AnticoagulantsPatients on Anticoagulants

Aspirin (ASA)Aspirin (ASA)

Coumadin (Warfarin)Coumadin (Warfarin)

HeparinHeparin

1Ridker et al Ann Intern Med 114:835-839, 1991.

Inherited Bleeding Inherited Bleeding DisordersDisorders

Hemophilia AHemophilia A Hemophilia B Hemophilia B

(Christmas (Christmas disease)disease)

Protein deficiencyProtein deficiency von Willebrand’s von Willebrand’s

diseasedisease Factor V Factor V

Antithrombin III Antithrombin III deficiencydeficiency

. . . Other factor . . . Other factor deficiencies (rare)deficiencies (rare)

Perioperative medical care:Perioperative medical care:

Surgical Surgical emergencyemergency

Cardiac diseaseCardiac disease Pulmonary diseasePulmonary disease Renal dysfunctionRenal dysfunction Liver dysfunctionLiver dysfunction DiabeticsDiabetics Bleeding disordersBleeding disorders MalnourishedMalnourished

Patients who are Patients who are malnourishedmalnourished

Proteins are essential for healing Proteins are essential for healing and regenerating tissueand regenerating tissue

Malnourished patients haveMalnourished patients have Higher wound complications Higher wound complications

(dehiscence) and greater anastomotic (dehiscence) and greater anastomotic leak rateleak rate

More postoperative muscle weakness More postoperative muscle weakness (diaphragm)(diaphragm)

Longer time in rehabilitationLonger time in rehabilitation

Treating Treating malnourishmentmalnourishment

““If the gut works, use it.”If the gut works, use it.” TPN vs. enteral feedsTPN vs. enteral feeds Preoperative “bulking Preoperative “bulking

up”up” Gastric and esophageal Gastric and esophageal

cancerscancers Why are they malnourished?Why are they malnourished?

How do you build someone How do you build someone up?up?

American Society of American Society of Anesthesiologists’ (ASA) Physical Anesthesiologists’ (ASA) Physical

Status AssessmentStatus AssessmentClassification Classification

(Elective)(Elective)ClassificationClassification

(Emergency)(Emergency)DescriptionDescription

11 1E1E Normally healthyNormally healthy

22 2E2E With mild systemic With mild systemic diseasedisease

33 3E3E With severe systemic With severe systemic disease that is not disease that is not

incapacitating incapacitating

44 4E4E With incapacitating With incapacitating systemic disease that is a systemic disease that is a

constant threat to lifeconstant threat to life

55 5E5E Moribound patient not Moribound patient not expected to survive expected to survive without operationwithout operation

66 6E6E Comatose/Organ DonorComatose/Organ Donor

Surgical ConsentSurgical Consent

Details of a particular surgical procedure:Details of a particular surgical procedure: ProcedureProcedure Preparation (bowel preparation; NPO Preparation (bowel preparation; NPO

guidelines)guidelines) Benefit from the procedureBenefit from the procedure Risks and potential complicationsRisks and potential complications

Answer questions of patients and relatives:Answer questions of patients and relatives: To dispel fear and alleviate anxietyTo dispel fear and alleviate anxiety

Patient PreparationPatient Preparation

Psychological:Psychological: Acceptance and positive outlookAcceptance and positive outlook

Physical:Physical: Skin preparationSkin preparation Bowel preparationBowel preparation Prophylactic antibioticsProphylactic antibiotics

Physiological:Physiological: Correcting associated co-morbid Correcting associated co-morbid

conditionsconditions Patient optimizationPatient optimization

A. Blood Orders:1. Type and screen or type and cross for

number of units appropriate to the procedure

B. Skin Preparation: 1. Hair removal best performed on day of surgery with an electric clipper 2. Pre-operative scrub or shower of the operative

site with a germicidal soap.

C. Pre-operative antibiotics: 1. Administer prophylactic antibiotics 30 min prior

to incision

D. Respiratory Care:

1. Pre-operative spirometry on the evening prior to surgery when indicated

2. Bronchodilators for moderate to severe COPD

E. Decompression of GI tract:

1. NPO after midnight

F. Intravenous fluids:

1. Maintenance rate overnight (D5LR)

G. Access and Monitoring lines:

1. At least one ga.18 IV needed for initiation of anesthesia

2. Arterial catheters and central or pulmonary artery catheters when indicated

H. Thromboembolic prophylaxis:1. When indicated (those predispose to deep venous thrombosis)

I. Pre-operative sedation:1. As ordered by the anesthesiologist

J. Special Consideration: 1. Maintenance medication

2. Pre-operative diabetic management 3. Other prophylactic medications 4. Peri-operative steroid coverage (if needed)

K. Skin Marking:1. For Plastic/Reconstructive Surgeries2. Marking of stoma sites

P. Pre-operative notes

Peri- and Post-operative CarePeri- and Post-operative Care

Reasons to MonitorReasons to Monitor

1.1. Patient safetyPatient safety

2.2. Positive outcomePositive outcome

3.3. Intra-operative case Intra-operative case adjustments adjustments

4.4. Assess equipment Assess equipment functionfunction

5.5. Improve patient vigilanceImprove patient vigilance

Peri- and Post-operative Peri- and Post-operative MonitoringMonitoring

Important aspects:Important aspects: Physiologic Monitoring:Physiologic Monitoring:

Vital SignsVital Signs HemodynamicHemodynamic RespiratoryRespiratory Gastric TonometryGastric Tonometry RenalRenal NeurologicNeurologic Metabolic/Nutritional Metabolic/Nutritional

Traditional 4 Cardinal Traditional 4 Cardinal Vital SignsVital Signs

Temperature:Temperature: Rectally or orallyRectally or orally Aural (Digital): measures core temperatureAural (Digital): measures core temperature

Heart Rate:Heart Rate: Cardiac rate Cardiac rate Pulse ratePulse rate

Blood Pressure:Blood Pressure: Standard BP apparatusStandard BP apparatus

Respiratory Rate:Respiratory Rate: Breaths per minuteBreaths per minute

Monitoring TemperatureMonitoring Temperature

Hemodynamic Hemodynamic MonitoringMonitoring

Purpose:Purpose: To monitor cardiovascular To monitor cardiovascular

function/performancefunction/performance Traditional tools unreliable (critically Traditional tools unreliable (critically

ill patients)ill patients) Methods:Methods:

Arterial CatheterizationArterial Catheterization Central Venous CatheterizationCentral Venous Catheterization Pulmonary Artery CatheterizationPulmonary Artery Catheterization

Arterial CatheterizationArterial Catheterization

Indications:Indications: Continuous monitoring of blood pressureContinuous monitoring of blood pressure Frequent sampling of arterial blood Frequent sampling of arterial blood

Contraindications:Contraindications: Severe occlusive arterial disease (distal Severe occlusive arterial disease (distal

ischemia)ischemia) Vascular prosthesis (graft)Vascular prosthesis (graft) Local infectionLocal infection Caution:Caution:

Bleeding diathesisBleeding diathesis Anticoagulant therapyAnticoagulant therapy


Clinical Utility:Clinical Utility: Systolic blood pressure (SBP)Systolic blood pressure (SBP) Diastolic blood pressure (DBP)Diastolic blood pressure (DBP) Mean arterial pressure (MAP)Mean arterial pressure (MAP) Pulse Rate Pulse Rate


Sites of catheterization:Sites of catheterization: Radial/UlnarRadial/Ulnar AxillaryAxillary FemoralFemoral Dorsalis pedisDorsalis pedis Superficial temporalSuperficial temporal BrachialBrachial

Assess CirculationAssess Circulation Allen’s test (E.V. Allen, 1929):Allen’s test (E.V. Allen, 1929):

patient makes tight fist for 1 min.patient makes tight fist for 1 min. radial & ulnar arteries compressedradial & ulnar arteries compressed one artery releasedone artery released observe color return in handobserve color return in hand repeat with other arteryrepeat with other artery

Allen’s Test FindingsAllen’s Test Findings Color return:Color return:

< 5 seconds - normal< 5 seconds - normal 5 - 15 seconds - delayed5 - 15 seconds - delayed > 15 seconds - abnormal> 15 seconds - abnormal


Complications:Complications: FailureFailure HematomaHematoma BleedingBleeding Occlusion and ischemiaOcclusion and ischemia InfectionInfection Fistulas/PseudoaneurysmsFistulas/Pseudoaneurysms Thrombo-embolismThrombo-embolism

Central Venous Central Venous CatheterizationCatheterization

Indications:Indications: Secure access:Secure access:

Fluid therapyFluid therapy Drug infusionsDrug infusions Parenteral nutritiona Parenteral nutritiona

Central venous pressure (CVP) monitoringCentral venous pressure (CVP) monitoring Others:Others:

Aspirate air emboli (neurosugery)Aspirate air emboli (neurosugery) Cardiac pacemaker placementCardiac pacemaker placement Hemodialysis Hemodialysis

Contraindications:Contraindications: Vessel thrombosisVessel thrombosis InfectionInfection Bleeding diathesis/anti-coagulant therapyBleeding diathesis/anti-coagulant therapy


Clinical Utility:Clinical Utility: Central venous pressure (CVP)Central venous pressure (CVP) Indirectly:Indirectly:

Right atrial pressureRight atrial pressure Right ventricular end-diastolic pressureRight ventricular end-diastolic pressure

Relationship between intravascular Relationship between intravascular volume and right ventricular functionvolume and right ventricular function


Sites of cetheterization:Sites of cetheterization: SubclavianSubclavian Internal jugularInternal jugular External jugularExternal jugular FemoralFemoral BrachiocephalicBrachiocephalic

Central Venous Central Venous PressurePressure


Complications:Complications: Pneumothorax (subclavian)Pneumothorax (subclavian) Arterial puncture (internal jugular and Arterial puncture (internal jugular and

femoral)femoral) Hematoma/bleedingHematoma/bleeding Injury (neurovascular)Injury (neurovascular) InfectionInfection Thrombo-embolismThrombo-embolism

Pulmonary Artery Pulmonary Artery CatheterizationCatheterization

Indications:Indications: Critically ill patientsCritically ill patients Extensive surgical procedure (cardiac Extensive surgical procedure (cardiac

surgery)surgery)

Contraindications:Contraindications: Vessel thrombosisVessel thrombosis InfectionInfection Bleeding diathesis/anti-coagulant therapyBleeding diathesis/anti-coagulant therapy

Pulmonary Artery Pulmonary Artery PressurePressure


Clinical Utility:Clinical Utility: Central venous pressure (CVP)Central venous pressure (CVP) Pulmonary artery diastolic pressure (PADP)Pulmonary artery diastolic pressure (PADP) Pulmonary artery systolic pressure (PASP)Pulmonary artery systolic pressure (PASP) Mean pulmonary artery pressure (MPAP)Mean pulmonary artery pressure (MPAP) Pulmonary artery occlusion “wedge” pressure Pulmonary artery occlusion “wedge” pressure

(PAOP)(PAOP) Cardiac output (CO)Cardiac output (CO) Indirectly:Indirectly:

Left atrial pressure (LAP)Left atrial pressure (LAP) Left ventricular end-diastolic pressure (LVEDP)Left ventricular end-diastolic pressure (LVEDP)


Sites of catheterization:Sites of catheterization: SubclavianSubclavian Internal jugularInternal jugular FemoralFemoral


Complications:Complications: Dysrhythmias (most common)Dysrhythmias (most common) Transient right bundle branch block Transient right bundle branch block

(RBBB)(RBBB) Coiling, looping, knotting of catheterCoiling, looping, knotting of catheter Aberrant catheter placementAberrant catheter placement InfectionInfection Thrombo-embolismThrombo-embolism BleedingBleeding

Respiratory MonitoringRespiratory Monitoring

Purpose:Purpose: To monitor respiratory performance:To monitor respiratory performance:

Ventilation/PerfusionVentilation/Perfusion Gas exchangeGas exchange Oxygen transportOxygen transport

To anticipate mechanical ventilatory To anticipate mechanical ventilatory support support

Methods:Methods: Ventilation monitoringVentilation monitoring Blood-Gas monitoringBlood-Gas monitoring

Ventilation MonitoringVentilation Monitoring Advantages:Advantages:

Predict and monitor ventilatory functionPredict and monitor ventilatory function Methods:Methods:

Lung volumes:Lung volumes: Tidal volumeTidal volume Vital capacityVital capacity Minute volumeMinute volume Dead spaceDead space

Pulmonary mechanics:Pulmonary mechanics: Inspiratory force/pressureInspiratory force/pressure Static complianceStatic compliance Dynamic characteristicDynamic characteristic Work of breathingWork of breathing

Lung VolumesLung Volumes

Tidal Volume:Tidal Volume: The volume of air moved in or out of the The volume of air moved in or out of the

lungs in a single breathlungs in a single breath Respiratory frequency Respiratory frequency (f) (f) : Tidal volume : Tidal volume

(Vt) ratio(Vt) ratio

Vital Capacity:Vital Capacity: The volume of maximal expiration The volume of maximal expiration

following a maximal inspirationfollowing a maximal inspiration 65 to 75 ml/kg (Normal)65 to 75 ml/kg (Normal)

Lung VolumesLung Volumes Minute Volume:Minute Volume:

Total ventilationTotal ventilation The total volume of air leaving the lung each The total volume of air leaving the lung each

minuteminute A product of Respiratory frequency ( A product of Respiratory frequency ( f f ) and Tidal ) and Tidal

Volume (Vt)Volume (Vt)

Dead Space:Dead Space: The portion of tidal volume not involved in gas The portion of tidal volume not involved in gas

exchangeexchange 2 components:2 components:

Anatomic dead space (within conducting airways)Anatomic dead space (within conducting airways) Alveolar dead space (within unperfused alveoli)Alveolar dead space (within unperfused alveoli)

Pulmonary MechanicsPulmonary Mechanics

Inspiratory Force:Inspiratory Force: Measured as the maximal pressure Measured as the maximal pressure

below atmospheric that a patient can below atmospheric that a patient can exert against an occluded airwayexert against an occluded airway

< -20 to -25 cmH2O (good recovery)< -20 to -25 cmH2O (good recovery) Compliance:Compliance:

Measure of the elastic properties of the Measure of the elastic properties of the lung and chest walllung and chest wall

60 to 100 ml/cmH2O (normal)60 to 100 ml/cmH2O (normal)

Pulmonary MechanicsPulmonary Mechanics Dynamic Characteristic:Dynamic Characteristic:

Evaluates compliance as well as impedance factorsEvaluates compliance as well as impedance factors Calculated by dividing the volume delivered by the Calculated by dividing the volume delivered by the

peak airway pressure minus the positive end peak airway pressure minus the positive end expiratory pressure (PEEP)expiratory pressure (PEEP)

50 to 80 ml/cmH20 (normal)50 to 80 ml/cmH20 (normal) Work of Breathing:Work of Breathing:

A measure of the process of overcoming the elastic A measure of the process of overcoming the elastic and frictional forces of the lung and chest walland frictional forces of the lung and chest wall

A product of the change in pressure and volumeA product of the change in pressure and volume 0.3 to 0.6 J/L (normal)0.3 to 0.6 J/L (normal)

Blood-Gas MonitoringBlood-Gas Monitoring

Advantages:Advantages: Efficiency of gas exchangeEfficiency of gas exchange Adequacy of alveolar ventilationAdequacy of alveolar ventilation Acid-base statusAcid-base status

Methods:Methods: Arterial blood gasArterial blood gas Mixed-venous blood gasMixed-venous blood gas CapnographyCapnography Pulse oximetryPulse oximetry

Pulse OximetryPulse Oximetry

Gastric TonometryGastric Tonometry

Purpose:Purpose: A reliable monitor in elective cardiac and A reliable monitor in elective cardiac and

major vascular surgerymajor vascular surgery A predictor of organ dysfunction and A predictor of organ dysfunction and

mortalitymortality Principle:Principle:

Noninvasive monitor of adequacy of aerobic Noninvasive monitor of adequacy of aerobic metabolism in organs whose superficial metabolism in organs whose superficial mucosal lining is vulnerable to low flow and mucosal lining is vulnerable to low flow and hypoxemia secondary to shock and SIRS hypoxemia secondary to shock and SIRS

Gastric TonometryGastric Tonometry

Values Derived:Values Derived: Intramucosal pHIntramucosal pH

Importance:Importance: Guides in the resuscitative managementGuides in the resuscitative management Provide a metabolic end point to Provide a metabolic end point to

resuscitationresuscitation Patient prognosticationPatient prognostication

Renal MonitoringRenal Monitoring

Purpose:Purpose: Monitor adequacy of perfusion Monitor adequacy of perfusion Prevention of parenchymal injury/failurePrevention of parenchymal injury/failure Predict drug clearance (proper dose Predict drug clearance (proper dose

management)management) Methods:Methods:

Urine output (0.5 to 1 ml/kg/hr)*Urine output (0.5 to 1 ml/kg/hr)* Glomerular function testGlomerular function test Tubular function testTubular function test

Glomerular Function Glomerular Function Test Test

Blood urea nitrogen (BUN):Blood urea nitrogen (BUN): Dependent on GFR and Urea productionDependent on GFR and Urea production Urea (increased):Urea (increased):

Prolonged TPNProlonged TPN GI BleedingGI Bleeding Catabolic states (Trauma, Sepsis and Catabolic states (Trauma, Sepsis and

Steroids) Steroids) Urea (decreased):Urea (decreased):

StarvationStarvation Liver DiseaseLiver Disease

Not a reliable monitor of renal functionNot a reliable monitor of renal function


Creatinine:Creatinine: Not influenced by protein metabolism and rate Not influenced by protein metabolism and rate

of fluid flow through renal tubulesof fluid flow through renal tubules

Serum creatinine:Serum creatinine: Directly proportional to creatinine production Directly proportional to creatinine production

(muscle mass and metabolism)(muscle mass and metabolism) Inversely proportional to GFR Inversely proportional to GFR

Takes 24 to 72 hrs before serum creatinine Takes 24 to 72 hrs before serum creatinine changes are reflectedchanges are reflected


24-hour Creatinine clearance:24-hour Creatinine clearance: Most reliable method for clinically Most reliable method for clinically

assessing GFRassessing GFR Most sensitive test for predicting renal Most sensitive test for predicting renal

dysfunction dysfunction Traditionally uses a 24-hr collectionTraditionally uses a 24-hr collection Currently uses 2-hr collection:Currently uses 2-hr collection:

Reasonable accurate and easier to performReasonable accurate and easier to perform

Tubular Function TestsTubular Function Tests

Purpose:Purpose: Measures concentrating ability of renal tubulesMeasures concentrating ability of renal tubules To differentiate causes of oliguria (pre-renal and To differentiate causes of oliguria (pre-renal and

ATN)ATN)

Methods:Methods: Fractional sodium excretion (most reliable)Fractional sodium excretion (most reliable)

Normal: 1-2%Normal: 1-2% BUN : Creatinine ratioBUN : Creatinine ratio Urine : Plasma Creatinine ratioUrine : Plasma Creatinine ratio

Neurologic MonitoringNeurologic Monitoring

Purpose:Purpose: Early recognition of cerebral Early recognition of cerebral

dysfunctiondysfunction Facilitate early and prompt interventionFacilitate early and prompt intervention

Methods:Methods: Intracranial pressure monitoringIntracranial pressure monitoring Electrophysiologic monitoringElectrophysiologic monitoring Transcranial doppler ultrasonographyTranscranial doppler ultrasonography Jugular venous oximetryJugular venous oximetry

Intracranial Pressure Intracranial Pressure MonitoringMonitoring

Methods:Methods: Intraventricular catheterIntraventricular catheter Subarachnoid boltSubarachnoid bolt Epidural boltsEpidural bolts Fiberoptic catheterFiberoptic catheter

Permits calculation of:Permits calculation of: Cerebral perfusion pressure (CPP) = MAP - ICPCerebral perfusion pressure (CPP) = MAP - ICP

Complications:Complications: InfectionInfection Malfunction/MalpositionMalfunction/Malposition HemorrhageHemorrhage ObstructionObstruction

Electrophysiologic Electrophysiologic MonitoringMonitoring

Electroencephalogram (EEG)Electroencephalogram (EEG) Indications:Indications:

Carotid endarterectomyCarotid endarterectomy Cerebrovascular surgeryCerebrovascular surgery Epilepsy surgeryEpilepsy surgery Open heart surgery (Some)Open heart surgery (Some)

Transcranial Doppler Transcranial Doppler UltrasoundUltrasound

Advantages:Advantages: NoninvasiveNoninvasive PortablePortable ReproducibleReproducible

Disadvantage:Disadvantage: Operator dependent (technical Operator dependent (technical

familiarity)familiarity)

Jugular Venous OximetryJugular Venous Oximetry

Applications:Applications: Carotid endarterectomyCarotid endarterectomy Neurosurgical proceduresNeurosurgical procedures Cardio-pulmonary bypassCardio-pulmonary bypass

Metabolic/NutritionalMetabolic/Nutritional

Purpose:Purpose: To determine the need to substitute To determine the need to substitute

artificial or parenteral feeding during artificial or parenteral feeding during the recovery phasethe recovery phase

Methods:Methods: Assessment of Caloric ExpenditureAssessment of Caloric Expenditure

Basal Energy Expenditure (BEE)Basal Energy Expenditure (BEE) Harris-Benedict EquationHarris-Benedict Equation

Assessment of Oxygen ConsumptionAssessment of Oxygen Consumption

Thank YouThank YouPamantasan ng Lungsod ng Maynila Pamantasan ng Lungsod ng Maynila

College of MedicineCollege of Medicine

Department of SurgeryDepartment of Surgery

pre- and post-operative monitoring of patients

Documents

central venous pressure

perioperative medical care

glomerular function test

central venous catheterization

operative medical care

pulmonary artery pressure

pulmonary artery catheterization

pulmonary disease