Skip to main content

New auto-weaning ventilator might make pulmonologists obsolete Part 1 (RCT, AJRCCM)



Maybe it’s the surgeons who are tired of consulting us for “vent management,” and finding out we can’t get patients off the vent any faster than they can without our help. Anyway, some troublemakers in Germany (Dirk Schadler et al) found that among 300 patients in surgical intensive care units (SICUs), an automatically-weaning ventilator was as good as human beings using a ventilator weaning protocol at liberating patients from mechanical ventilation.



What They Did
Authors randomized 300 post-surgical patients at 3 SICUs at one hospital in Kiel, Germany after they had been on 9 hours of mechanical ventilation to one of two weaning strategies. Half were managed with standard ventilator-weaning protocols, managed by physicians and respiratory therapists. Half had a switch on their ventilators (Evita XL) flipped to enable the SmartCare software embedded into it. This software automatically adjusts the pressure support delivered in response to patient effort, aiming to keep a patient in a “comfort zone” of 15-30 breaths per minute, with expired paCO2 of < 55 mm Hg, and tidal volumes greater than 300 mL. PEEP had to be set and changed manually.
When the patient is staying in the respiratory comfort zone with a minimum of pressure support and PEEP, the clever ventilator automatically initiates a spontaneous breathing trial. If the patient passes the machine-initiated and monitored SBT, the ventilator goes “DING!“, then extubates the patient and transfers them out of the ICU (I’m making up this last part…I think).
The study’s primary endpoint was overall ventilation time in the ICU, including noninvasive ventilation (NIPPV/BiPAP), during the 28-day study period. Secondary end points were time in the respiratory “comfort zone”, numbers of alarms and vent changes, length of stay in the ICU and hospital, and mortality at 28- and 90-days.
They predefined three subgroups: cardiac surgery patients (n=132), patients with sepsis (n=44), and patients with COPD (n=41).
The study was funded in large part by a grant of 70,000 euros from Drager, the company that makes the SmartCare software.
What They Found
Overall, patients were weaned/liberated from mechanical ventilation equally quickly in both groups: a median of 31 hours in the automatic-weaning group, and 39 hours in the humans-using-weaning-protocols group (p=0.18).
In the predefined cardiac surgery subgroup (n=132), patients on the automatic-weaning vent were liberated a bit faster: 24 hours of ventilation, vs. 35 hours for controls.
In the sepsis and COPD subgroups, there was no statistically significant difference in ventilator hours, but numerical results were widely discordant:
  • 44 patients with sepsis “auto-weaned” in a median 101 hours (5 days) vs. 144 hours (7 days) for the human-weaning group. (p=0.296)
  • 41 patients with COPD took longer to escape the ventilator on auto-weaning than with standard human-driven protocols (55 hours vs. 28 hours, p=0.095).
There were abundant protocol violations: 25% of the time the automatic weaning software was supposed to be “on,” it was not. This would seem to make it harder to show a benefit (i.e., reduce the observed effect of auto-weaning).
Patients in the auto-wean group were placed on their first spontaneous breathing trial (SBT) by the machine within one hour in a majority of cases; those managed by humans took a median of 9 hours to start an SBT. There was a “trend” toward fewer tracheostomies in the automatic-weaning group (17 vs. 28, p=0.08).
Labels:

Comments

Post a Comment

Popular posts from this blog

power injectable peripherally inserted central catheters

Clinical experience with power injectable peripherally inserted central catheters in intensive care patients     Introduction In intensive care units (ICU), peripherally inserted central catheters (PICC) may be an alternative option to standard central venous catheters, particularly in patients with coagulation disorders or at high risk for infection. Some limits of PICCs (such as low flow rates) may be overcome by the use of power-injectable catheters . Method We have retrospectively reviewed all the power injectable PICCs inserted in adult and pediatric patients in the ICU during a 12-month period, focusing on the rate of complications at insertion and during maintenance. Results We have collected 89 power injectable PICCs (in adults and in children), both multiple and single lumen. All insertions were successful. There were no major complications at insertion and no episodes of catheter-related blood stream infection. Non-infective complications ...
1 comment
Read more

The 12 decision making steps for post dural puncture headache treatment

Treatment decision-making algorithm for postdural puncture headache. 1. When diagnosis is made, all patients should receive supportive measures (reassurance, bed rest, analgesics, hydration, quiet environment). 2. Severity of symptoms should be classified using VAS scale (mild 1–3, moderate 4–6, severe 7–10). 3. Virtually all patients will improve in time even without additional therapy. (dashed lines) 4. Symptoms worsen or fail to resolve within 5 days. 5. Patient preference dictates the choice between pharmacologic (less effective) and epidural blood patch (EBP). 6. In patients with severe symptoms, EBP is strongly suggested. 7. The most common pharmacologic measure is  caffeine  prescription. 8. The failure, worsening, or recurrence of symptoms after pharmacologic measures favors the use of EBP. 9. In addition to EBP, other epidural treatment options can be considered in select patients (eg,  dextran , saline). 10. A period of 24 h should lapse before repeating EBP. 11...
1 comment
Read more

Things to Avoid in Anesthesia for Pregnant with Pulmonary hypertension

Anesthesia for Pregnant woman with Pulmonary Hypertension is a real challenge for anesthesiologist. It is very crucial to remember the pathophysiology of pulmonary hypertension in pregnant women and to avoid some practices that will worsen the cardiac status. 1-Avoid single shot spinal anesthesia. Some authorities consider pulmonary hypertension as absolute contraindication for single shot spinal anesthesia specially in patients with NYHA III ,IV. Spinal anesthesia causes major hemodynamic instability(decrease SVR, decrease VR, decrease in CO) The preferred neuroaxial techniques are (epidural anesthesia and CSE with minimal spinal dose) 2-Avoid PAC. Pulmonary Artery catheters insertion may lead to pulmonary artery rupture or thrombosis. TEE is better cardiac monitor/Arteial line is mandatory. 3-Avoid Nitrous oxide in gas mixture.N2O increase the PVR 4-If MV to be started, avoid High TV and PEEP 5-Avoid Oxytocin Boluses, or rapid administration of Pitocin. Oxytocin causes ...
Post a Comment
Read more