In the absence of evidence of acute cerebral herniation, normal ventilation is recommended for patients with traumatic brain injury (TBI). Despite this recommendation, ventilation strategies vary during the initial management of patients with TBI and may impact outcome. The goal of this systematic review was to define the best evidence-based practice of ventilation management during the initial resuscitation period.

A literature search of PubMed, CINAHL, and SCOPUS identified studies from 2009 through 2019 addressing the effects of ventilation during the initial post-trauma resuscitation on patient outcomes.

The initial search yielded 899 articles, from which 13 were relevant and selected for full-text review. Six of the 13 articles met the inclusion criteria, all of which reported on patients with TBI. Either end-tidal carbon dioxide (ETCO2) or partial pressure carbon dioxide (PCO2) were the independent variables associated with mortality. Decreased rates of mortality were reported in patients with normal PCO2 or ETCO2.

Normoventilation, as measured by ETCO2 or PCO2, is associated with decreased mortality in patients with TBI. Preventing hyperventilation or hypoventilation in patients with TBI during the early resuscitation phase could improve outcome after TBI.

After congenital heart surgery, some patients may need long-term mechanical ventilation because of chronic respiratory failure. In this study, we analysed outcomes of the patients who need tracheostomy and home mechanical ventilation.

Amongst 1343 patients who underwent congenital heart surgery between January, 2014 and June, 2018, 45 needed tracheostomy and HMV. The median age of these patients was 6.4 months (12 days–6.5 years). Nineteen patients underwent palliation while 26 patients underwent total repair. Post-operative diaphragm plication was performed in five patients (11%). Median duration of mechanical ventilation before tracheostomy was 32 days (8–154 days). The patients were followed up with their home ventilators in ward and at home. Mean follow-up time was 36.24 ± 11.61 months.

The median duration of ICU stay after tracheostomy was 27 days (range 2–93 days). Follow-up time in ward was median 30 days (2–156 days). A total of 12 patients (26.6%) were separated from the ventilator and underwent decannulation during hospital stay. Thirty-two patients (71.1%) were discharged home with home ventilator support. Of them, 15 patients (46.9%) were separated from the respiratory support in median of 6 weeks (1 week–11 months) and decannulations were performed. Total mortality was 31.1%. in which four patients are still HMV dependent. There was no significant difference for decannulation between total repair and palliation patients.

HMV via tracheostomy is a useful option for the treatment of children who are dependent on long-term ventilation after congenital heart surgery although there are potential risks.

To analyse the changes of different ventilation on regional cerebral oxygen saturation and cerebral blood flow in infants during ventricular septal defect repair.

Ninety-two infants younger than 1 year were enrolled in the study. End-expiratory tidal pressure of carbon dioxide was maintained at 40–45 and 35–39 mmHg in relative low and high ventilation groups. Regional cerebral oxygen saturation and flow velocity of the middle cerebral artery were recorded after anaesthesia (T0), cut pericardium (T1), separation from cardiopulmonary bypass (T2), the end of modified ultrafiltration, (T3) and at the end of operation (T4).

The relative low ventilation group exhibited a significantly high regional cerebral oxygen saturation at each time point except for T2 (T0:77 ± 4, T1:76 ± 5, T3:76 ± 8, T4:76 ± 8, respectively, p < 0.001). Flow velocity of the middle cerebral artery in the relative low ventilation group was higher compared to the relative high ventilation group at each time point except for T2 (T0:53 ± 14, T1:54 ± 15, T3:53 ± 17, T4:52 ± 16, respectively, p < 0.001). Between the two groups, T2 showed the lowest middle cerebral artery flow velocity (relative low ventilation: 39 ± 15, relative high ventilation: 39 ± 11, p < 0.001).

The infants’ regional cerebral oxygen saturation and middle cerebral artery flow velocity performed better in the range of 40–45 mmHg end-expiratory tidal pressure of carbon dioxide during CHD surgery. Modified ultrafiltration increased cerebral oxygen saturation. It was important to regulate ventilation in order to balance cerebral oxygen in infants.

The 2017 International Liaison Committee on Resuscitation (ILCOR) guideline recommends that Emergency Medical Service (EMS) providers can perform cardiopulmonary resuscitation (CPR) with synchronous or asynchronous ventilation until an advanced airway has been placed. In the current literature, limited data on CPR performed with continuous compressions and asynchronous ventilation with bag-valve-mask (BVM) are available.

In this study, researchers aimed to compare the effectiveness of asynchronous BVM and laryngeal mask airway (LMA) ventilation during CPR with continuous chest compressions.

Emergency medicine residents and interns were included in the study. The participants were randomly assigned to resuscitation teams with two rescuers. The cross-over simulation study was conducted on two CPR scenarios: asynchronous ventilation via BVM during a continuous chest compression and asynchronous ventilation via LMA during a continuous chest compression in cardiac arrest patient with asystole. The primary endpoints were the ventilation-related measurements.

A total of 92 volunteers were included in the study and 46 CPRs were performed in each group. The mean rate of ventilations of the LMA group was significantly higher than that of the BVM group (13.7 [11.7-15.7] versus 8.9 [7.5-10.3] breaths/minute; P <.001). The mean volume of ventilations of the LMA group was significantly higher than that of the BVM group (358.4 [342.3-374.4] ml versus 321.5 [303.9-339.0] ml; P = .002). The mean minute ventilation volume of the LMA group was significantly higher than that of the BVM group (4.88 [4.15-5.61] versus 2.99 [2.41-3.57] L/minute; P <.001). Ventilations exceeding the maximum volume limit occurred in two (4.3%) CPRs in the BVM group and in 11 (23.9%) CPRs in the LMA group (P = .008).

The results of this study show that asynchronous BVM ventilation with continuous chest compressions is a reliable and effective strategy during CPR under simulation conditions. The clinical impact of these findings in actual cardiac arrest patients should be evaluated with further studies at real-life scenes.

Coronavirus disease 2019 is an international pandemic. One of the cardinal features is acute respiratory distress syndrome, and proning has been identified as beneficial for a subset of patients. However, proning is associated with pressure-related side effects, including injury to the nose and face.

This paper describes a pressure-relieving technique using surgical scrub sponges. This technique was derived based on previous methods used in patients following rhinectomy.

The increased use of prone ventilation has resulted in a number of referrals to the ENT team with concerns regarding nasal pressure damage. The described technique, which is straightforward and uses readily available materials, has proven effective in relieving pressure in a small number of patients.

Hyperventilation during cardiopulmonary resuscitation (CPR) negatively affects cardiopulmonary physiology. Compression-adjusted ventilations (CAVs) may allow providers to deliver ventilation rates more consistently than conventional ventilations (CVs). This study sought to compare ventilation rates between these two methods during simulated cardiac arrest.

That CAV will not result in different rates than CV in simulated CPR with metronome-guided compressions.

Volunteer Basic Life Support (BLS)-trained providers delivered bag-valve-mask (BVM) ventilations during simulated CPR with metronome-guided compressions at 100 beats/minute. For the first 4-minute interval, volunteers delivered CV. Volunteers were then instructed on how to perform CAV by delivering one breath, counting 12 compressions, and then delivering a subsequent breath. They then performed CAV for the second 4-minute interval. Ventilation rates were manually recorded. Minute-by-minute ventilation rates were compared between the techniques.

A total of 23 volunteers were enrolled with a median age of 36 years old and with a median of 14 years of experience. Median ventilation rates were consistently higher in the CV group versus the CAV group across all 1-minute segments: 13 vs 9, 12 vs 8, 12 vs 8, and 12 vs 8 for minutes one through four, respectively (P <.01, all). Hyperventilation (>10 breaths per minute) occurred 64% of the time intervals with CV versus one percent with CAV (P <.01). The proportion of time which hyperventilation occurred was also consistently higher in the CV group versus the CAV group across all 1-minute segments: 78% vs 4%, 61% vs 0%, 57% vs 0%, and 61% vs 0% for minutes one through four, respectively (P <.01, all).

In this simulated model of cardiac arrest, CAV had more accurate ventilation rates and fewer episodes of hyperventilation compared with CV.

Nikolla DA, Kramer BJ, Carlson JN. A cross-over trial comparing conventional to compression-adjusted ventilations with metronome-guided compressions. Prehosp Disaster Med. 2019;34(2):220–223

Chemical-biological-radio-nuclear (CBRN) gas masks are the standard means for protecting the general population from inhalation of toxic industrial compounds (TICs), for example after industrial accidents or terrorist attacks. However, such gas masks would not protect patients on home mechanical ventilation, as ventilator airflow would bypass the CBRN filter. We therefore evaluated in vivo the safety of adding a standard-issue CBRN filter to the air-outflow port of a home ventilator, as a method for providing TIC protection to such patients.

Eight adult patients were included in the study. All had been on stable, chronic ventilation via a tracheostomy for at least 3 months before the study. Each patient was ventilated for a period of 1 hour with a standard-issue CBRN filter canister attached to the air-outflow port of their ventilator. Physiological and airflow measurements were made before, during, and after using the filter, and the patients reported their subjective sensation of ventilation continuously during the trial.

For all patients, and throughout the entire study, no deterioration in any of the measured physiological parameters and no changes in measured airflow parameters were detected. All patients felt no subjective difference in the sensation of ventilation with the CBRN filter canister in situ, as compared with ventilation without it. This was true even for those patients who were breathing spontaneously and thus activating the ventilator’s trigger/sensitivity function. No technical malfunctions of the ventilators occurred after addition of the CBRN filter canister to the air-outflow ports of the ventilators.

A CBRN filter canister can be added to the air-outflow port of chronically ventilated patients, without causing an objective or subjective deterioration in the quality of the patients’ mechanical ventilation. (Disaster Med Public Health Preparedness. 2018;12:739-743)

Ventilation with a bag valve mask (BVM) is a challenging but critical skill for airway management in the prehospital setting.

Tidal volumes received during single rescuer ventilation with a modified BVM with supplemental external handle will be higher than those delivered using a standard BVM among health care volunteers in a manikin model.

This study was a randomized crossover trial of adult health care providers performing ventilation on a manikin. Investigators randomized participants to perform single rescuer ventilation, first using either a BVM modified by addition of a supplemental external handle or a standard unmodified BVM (Spur II BVM device; Ambu; Ballerup, Denmark). Participants performed mask placement and delivery of 10 breaths per minute for three minutes, as guided by a metronome. After a three-minute rest period, they performed ventilation using the alternative device. The primary outcome measure was mean received tidal volume as measured by the manikin (IngMar RespiTrainer model; IngMar Medical; Pittsburgh, Pennsylvania USA). Secondary outcomes included subject device preference.

Of 70 recruited participants, all completed the study. The difference in mean received tidal volume between ventilations performed using the modified BVM with external handle versus standard BVM was 20 ml (95% CI, -16 to 56 ml; P=.28). There were no significant differences in mean received tidal volume based on the order of study arm allocation. The proportion of participants preferring the modified BVM over the standard BVM was 47.1% (95% CI, 35.7 to 58.6%).

The modified BVM with added external handle did not result in greater mean received tidal volume compared to standard BVM during single rescuer ventilation in a manikin model.

ReedP, ZobristB, CasmaerM, SchauerSG, KesterN, AprilMD. Single Rescuer Ventilation Using a Bag Valve Mask with Removable External Handle: A Randomized Crossover Trial. Prehosp Disaster Med. 2017;32(6):625–630.