Questions · Intraoperative Lung-Protective Ventilation
9 questions, 0 approved. Approve them one at a time — a quiz shows nothing you have not.
Recall — derived from a kept point
State the initial ventilator settings recommended by international expert consensus on lung-protective ventilation for a surgical patient - tidal volume with its weight basis, and PEEP - what should be done with PEEP after that, and the principle to follow when performing a recruitment manoeuvre.
Answer: Set an initial tidal volume of 6-8 mL/kg predicted body weight with PEEP 5 cmH2O, then individualise the PEEP. When recruiting, use the lowest effective pressure for the shortest effective time.
6-8 mL/kg of predicted body weight with PEEP 5 is a starting point, not the final setting - the PEEP gets individualised from there.
Source claim: Set the ventilator initially to a tidal volume of 6-8 mL/kg predicted body weight with PEEP 5 cmH2O, then individualise the PEEP; when recruiting, use the lowest effective pressure for the shortest effective time.
Lung-Protective Ventilation for the Surgical Patient: International Expert Panel-Based Consensus Recommendations, British journal of anaesthesia 2019
recall · CA-1 · phrased by llm
In an individual patient data meta-analysis of protective versus conventional intraoperative ventilation, which ventilator variable did the dose-response for postoperative pulmonary complications track, and what happened when high PEEP was added to an already low tidal volume?
Answer: The dose-response tracked tidal volume, not PEEP. Adding high PEEP on top of an already low tidal volume gave no further reduction in postoperative pulmonary complications.
In that pooled data the tidal volume was doing the work - piling PEEP on top of an already low tidal volume added nothing.
Source claim: The dose-response for postoperative pulmonary complications tracks tidal volume, not PEEP: adding high PEEP to an already low tidal volume gave no further reduction.
Protective Versus Conventional Ventilation for Surgery: A Systematic Review and Individual Patient Data Meta-Analysis, Anesthesiology 2015
recall · CA-2 · phrased by llm
In a randomised trial of intraoperative low-tidal-volume, lung-protective ventilation during major abdominal surgery, give the effect on major pulmonary and extrapulmonary complications and on the need for postoperative ventilation or reintubation, with the event rates for each.
Answer: Major pulmonary and extrapulmonary complications fell from 27.5% to 10.5%, and the need for postoperative ventilation or reintubation fell from 17% to 5%.
Those are large absolute differences, and they were shown after major abdominal surgery - that is the population the numbers describe.
Source claim: Lung-protective ventilation cut major pulmonary and extrapulmonary complications after major abdominal surgery from 27.5% to 10.5%, and the need for postoperative ventilation or reintubation from 17% to 5%.
A Trial of Intraoperative Low-Tidal-Volume Ventilation in Abdominal Surgery, The New England journal of medicine 2013
recall · CA-2 · phrased by llm
A Bayesian individual patient data meta-analysis of three randomised trials compared high PEEP with recruitment manoeuvres against low PEEP, reporting an odds ratio of 0.67 (0.50 to 0.87) for postoperative pulmonary complications in laparoscopic surgery. Say how strongly you should state this finding to a resident, and for which surgical setting.
Answer: State it as a possible rather than an established benefit: high PEEP with recruitment manoeuvres may reduce postoperative pulmonary complications, especially in laparoscopic surgery, where the odds ratio was 0.67 (0.50 to 0.87). The finding is hedged as 'may reduce', and laparoscopic surgery is the setting where it is described.
Say 'may reduce' - this is pooled trial data with the clearest signal in laparoscopic surgery, not a settled rule for every case.
Source claim: High PEEP with recruitment maneuvers may reduce postoperative pulmonary complications, especially in laparoscopic surgery (OR 0.67 [0.50 to 0.87]).
High Positive End-Expiratory Pressure (PEEP) With Recruitment Maneuvers Versus Low PEEP During General Anesthesia for Surgery: A Bayesian Individual Patient Data Meta-Analysis of Three Randomized Clinical Trials, Anesthesiology 2025
recall · CA-3 · phrased by llm
In a 69,265-patient registry, a PEEP of ___ cmH2O and a plateau pressure of 16 cmH2O or less were the settings associated with the lowest risk of postoperative respiratory complications.
Answer: 5
In a 69,265-patient registry, a PEEP of 5 cmH2O and a plateau pressure of 16 cmH2O or less were the settings associated with the lowest risk of postoperative respiratory complications.
Intraoperative Protective Mechanical Ventilation and Risk of Postoperative Respiratory Complications: Hospital Based Registry Study · PMID 26174419
recall · CA-2 · phrased by derived
The point with one number taken out. No model wrote any of this: the stem is the sentence you reviewed, minus a digit, and the paper it came from is named beneath it.
Open prompts
How does your plan change if the patient is not optimised?
open · CA-2 · phrased by derived
What is the physiology behind what we just did?
open · CA-2 · phrased by derived
Talk me through the trade-off you made there.
open · CA-2 · phrased by derived
What would make you abandon this plan and do something else?
open · CA-2 · phrased by derived
Questions only — nothing here asserts anything, which is why a model is allowed to phrase them. Where no model was reachable these are the level defaults.