Repeated Medical PG Question- 86

 

#ANESTHESIA (INI-CET)

Q- A patient was in surgery when suddenly a resident noticed the following plot on the capnograph monitor. What should be the immediate next step in the manage­ment of the patient?

A. Increase muscle relaxant

B. Increase the depth of anesthesia

C. Check tubes for any blockage

D. Change soda-lime

 

Answer: A. Increase muscle relaxant

Curare cleft- Clefts are seen in the plateau portion of the capnograph is due to patient own respiratory effort because of inadequate muscle relaxation.

▪️They appear when muscle relaxants begin to subside and spontaneous ventilation returns 

▪️Deapth of cleft is inversely proportional to degree of drug activity

▪️Position is fairly constant on the same patient, but not necessarily present with every breath

▪️Increasing the dose of muscle relaxant will solve this problem.

Q- Dose of which of the following muscle relaxant has to be calculated on the basis of total body weight of an obese person rather than its ideal weight

     A. Atracurium

     B. Vecuronium

     C. Pancuronium

     D. Rocuronium

Answer is A. Atracurium

▪️Atracurium is a commonly used nondepolarizing neuromuscular blocking agent whose disposition depends on Hofmann elimination and non-specific esterase hydrolyses and is independent of liver and kidney function.

▪️As a result, dosing of atracurium based on lean body mass total body weight and total body weight with a dose reduction for every 10 kg more than 70 kg have been proposed

Q- An infant with respiratory distress was intubated. The fastest and accurate method to confirm intubation

    A. Capnography

    B. Clinically by auscultation

    C. Chest radiography

    D. Airway pressure measurement

Answer is A. Capnography

• Capnography is the surest confirmatory sign of correct intubationQ
• So, the fastest and accurate method to confirm intubation in the above mentioned infant is capnography

Capnography

• Capnography is the continuous measurement of end tidal carbon dioxide (ETCO,) and its waveform.
• Normal: 32 to 42 mmHe (3 to 4 mmHg less than arterial pCO, which is 35 to 45 mmHg)
• Principle: Infrared light is absorbed by carbon dioxide

Uses of Capnography

• It is the surest confirmatory sign of correct intubation  (esophageal intubation will yield ETCO2=0)
• Intraoperative displacement of endotracheal tube° (ETCO₂ will become zero)
• Diagnosis of malignant hyperthermie (ETCO, may rise to more than 100 mm Hg)
• For detecting obstructions and disconnections of endotracheal tubes (ETCO, will fall)

Uses of Capnography

• Diagnosing pulmonary embolism by air, fat or thrombus (sudden fall of ETCO₂ occurs. It may
• become zero if embolus is large enough to block total pulmonary circulation)
• Exhausted sodalime or defective valves of closed circuit will show high ETCO₂ values.
• To control level of hypocapnia during hyperventilation in neurosurgery
• Indicator of cardiac output. In cardiac arrest ETCO, is zero.