End Tidal Carbon Dioxide Monitoring During Moderate Sedation
End Tidal Carbon Dioxide Monitoring During Moderate Sedation
CO2 monitoring through non-invasive methods may provide an early warning sign of
 hypoventilation during procedural sedation.
Sedation is a drug-induced depression in the level of consciousness. The clinical objectives
 of administering sedation for GI endoscopy are to relieve patient anxiety and discomfort,
 improve the outcome of the examination, and diminish the patient's memory of the event. A
 number of different sedatives and analgesics can be used to achieve appropriate levels of
 sedation for GI endoscopic procedures. The targeted level of sedation may vary depending on
 patient and procedural variables, and doses of sedatives should be titrated accordingly to
 achieve a safe, comfortable, and technically successful endoscopic procedure. Knowledge of
 the pharmacologic profiles of sedation agents is necessary to maximize the likelihood that
 the desired level of sedation is achieved.(1) All patients receiving sedation to facilitate
 endoscopic procedures should have monitoring of cardiorespiratory parameters before, during,
 and after administration of sedation/analgesia. Electronic monitoring may detect early signs
 of patient distress and is an adjunct to continuous clinical assessment. Commonly used
 monitoring equipment for patients undergoing endoscopic procedures includes pulse oximetry,
 single-lead continuous electrocardiographic (ECG) monitoring, and automated blood pressure
 monitoring. With the increased use of propofol to facilitate endoscopy in recent years, less
 familiar monitoring devices have been introduced, including end-tidal carbon dioxide (EtCO2)
 and level of consciousness monitors. Given a recent change in the American Society of
 Anesthesiologists (ASA) guidelines, recommending CO2 monitoring for patients undergoing both
 moderate and deep sedation, familiarity with capnography may become necessary.(2) Patients
 are at risk of respiratory depression and acute hypercapnia during sedation and recovery from
 anaesthesia . Desaturation on pulse oximetry for monitoring of hypoventilation is a late
 sign. Moreover, hypoventilation is masked by administration of supplemental O2. ( 3) For a
 sedated patient in spontaneous ventilation, hypoventilation (by airway obstruction or central
 respiratory depression) will likely precede hypoxemia. Hence, if the patient is monitored
 using a capnograph machine, when hypoventilation occurs, PEtCO2 increases and the shape of
 the capnography curve is modified.This may trigger an adequate response from the person
 monitoring the anesthesia (chin thrust, sedative dose modification, oxygen supplementation)
 so as to prevent hypoxemia. (5) Measuring CO2 noninvasively includes capnography and
 capnometry. capnography provides numerical and graphical (waveforms) forms, while capnometry
 provides only numerical form. (6) Arterial blood gas (ABG) can tell us about the patient's
 acid-base balance, which is measured by the hydrogen ion (H) concentration in the blood (pH),
 oxygen saturation (SaO2), partial pressure of oxygen (PaO2), partial pressure of carbon
 dioxide (PaCO2), concentration of bicarbonate (HCO3), base excess and base deficit.(7) ABG
 results can indicate how effectively the patient's body is compensating for the acid-base
 disturbance and whether the patient's total blood volume is adequate for transporting all the
 nutrients that the body's tissues require. (8)

 Hyopthesis of this trial: is CO2 monitoring through non-invasive methods may provide an early
 warning sign of hypoventilation during procedural sedation.

 Primary outcome: Measuring end-tidal carbon dioxide (EtCO2) that is taken during different
 flows of oxygen(O2) supplementation.

 Secondary outcome: Will include O2 saturation, haemodynamics (systolic blood pressure,
 diastolic blood pressure and mean blood pressure), time to recovery, patient satisfaction,
 Ramsay sedation scale (which is used to measure level of sedation through dividing patients
 level of sedation into 6 categories ranging from severe agitation to deep coma). (9) Ramsay
 Sedation Scale

 1. Patient is anxious and agitated or restless, or both.

 2. Patient is co-operative, oriented, and tranquil.

 3. Patient responds to commands only.

 4. Patient exhibits brisk response to light glabellar tap or loud auditory stimulus.

 5. Patient exhibits a sluggish response to light glabellar tap or loud auditory stimulus.

 6. Patient exhibits no response.
Inclusion Criteria:

 -  Age: Adult Patients aged 20-60 years.

 -  Sex: either male or female.

 -  ASA physical status I or II.

 -  Elective ERCP

 Exclusion Criteria:

 -  * Abnormal renal function test.

 -  History of asthma or COPD

 -  patients with a history of hypertension and diabetes.

 -  Cardiac patients.