Respiratory Failure & Mechanical Ventilation

Air leak or Air trapping?

69 years old with anoxic encephalopathy and acute right parietal infarct after cardiac arrest. On Volume control mode of ventilation with VT of 510 breathing

What do you think?

62 years old female who was intubated for acute on chronic hypercapnic respiratory failure secondary to COPD exacerbation. Her ideal body weight is 67 Kg. CXR shows severely hyperinflated lungs.

Patient was placed on AC mode of ventilation with VT of 450 mL, RR of 22 per minute, and an inspiratory flow of 60 L/min. Her minute ventilation was 10 liters per minute.

Blood gases revealed acute on chronic respiratory acidosis with pH of 7.22 and pCO2 of 75

An inspiratory hold maneuver was done and shown in the following screenshot:

‎‏Age/gender : 54y/o male

‎

📝 ‎‏ Diagnosed as ARDS, H1N1 positive, later found to have ICH

‎‏ 🗂️ Medical history : Nil

🏋🏻‍♂️ ‎‏Adm wt.60kg, ht.168cm.

‎‏ Current wt: 54.0

67 year old who eas intubated and placed on the ventilator for COPD exacerbation. Respiratory rate increased from 13 to 142 per minute

What should you do?

64 years old male who is a heavy smoker with COPD and laryngeal carcinoma, s/p tracheostomy. He is addmitted now to the ICU complaining of air hunger. When connected to the ventilator; it showed the waves you see and the patient felt suffocation. Unfortunately, this is the only screenshot that was provided by Dr. Abdulhaseeb Tarabulsi.

Knowing that this is not a ventilator malfunction or circuit disconnection, what do you thing is happening?

Suction me please!

Ventilator graphic of an intubated asthmatic patient on mechanical ventilation showing mild persistent flow at end of expiration indicating auto-PEEP:

The ventilator settings were changed as the following:

VT decreased from 470 to 420 mL.

Rate decreased from 20 to 16 breaths per minute but the patient is still breathing over.

The inspiratory time was decreased from 0.9 second to 0.6 second.

How do you explain the the drop in the pressure indicated by the white arrows on the pressure/time scalar?

@Everyone

Please answer the question and provide your input in the comment section!

PRVC mode of ventilation with a targeted VT of 400, RR 26 and I:E ratio of 1:1.5. Notice the dynamic hyperinflation (autoPEEP) with persistent flow at end of expiration and the ineffective triggers.

Ventilator settings were adjusted to allow longer expiration by decreasing the rate to 20 per minute, and decreasing inspiratory time with I:E at 1:2.9. The volume was also increased to 450 ml.

Dynamic hyperinflation improved remarkably and now the ventilator is triggered with every inspiratory effort of the patient.

47 years old female with status asthmatics who got intubated and placed on mechanical ventilation. An inspiratory hold was applied as shown in this snapshot of the ventilator screen:

Notice the limitation of the expiratory flow in the first breath before the inspiratory hold. Also notice that the peak pressure is elevated at 46 cm H2O, the plateau is elevated at 30 cm H2O and the difference is at 16 cm H2O representing the increased airway resistance due to bronchospasm.

What would you do next to confirm your diagnosis?

65 year-old male with acute respiratory failure secondary to pulmonary edema who was intubated and placed on mechanical ventilation. His course was complicated with left parietal occipital and temporal infarction. The following graphs have been observed;

Please identify the abnormality and answer the following question:

65 years old with submasdive pulmonary embolism, DVT, atrial flutter, and non-ischemic cardiomyopathy. Intubated and placed on mechanical ventilation at night (A/C mode VT 500, Flow of 50, RR 22 and PEEP 5). The following was observed during the morning round:

Based on the pressure over time waveform, how would you approach this case?

Please see comments for the answer!

Please notice the volume over time scalar as indicated by the light orange arrow and provide your feedback:

@Everyone

Please select your answer and you may provide your explanation in the comment section.

Please see comments for explanation!

The respiratory drive is the intensity of the neural stimulus that determines how much the respiratory muscles contract. Excessive or low respiratory drive can be encountered in different clinical scenarios in patients on mechanical ventilation. High respiratory drive potentially leads to an injurious effect on the diaphragm (myotrauma), and on the lung (patient-self-inflicted lung injury). The low respiratory drive may cause disuse atrophy which leads to difficulty in weaning off the ventilator. Occlusion pressure at 100 ms (P 0.1) is the negative pressure measured 100 ms after the initiation of an inspiratory effort performed against a closed respiratory circuit and has been used as an indirect measure of the respiratory drive.

Please observe the P0.1 procedure and value in the. Above graph and provide your answer to this question:

Please examine the pressure and flow waveforms in the above graph and determine the abnormality:

Observe the flow/time and the volume/time waveforms, compare with the flow/volume loop and make your diagnosis:

Double-triggering seen in flow and volume waveforms from volume-controlled ventilation. Continued subject effort during the second breath causes the airway pressure to drop below the trigger threshold, which initiates an additional “stacked” breath. Note the large increase in peak airway pressure caused by the stacked breath and the high peak expiratory flow following the stacked breath.

How can you explain the pressure/time and flow/time tracings in the above scalars?

Decreasing plateau pressure with inspiratory hold in a patient with a pneumothorax and chest tube in place indicating continued air leak!