Optimal inspiratory pressure for face mask ventilation in paralyzed and unparalyzed children to prevent gastric insufflation: a prospective, randomized, non-blinded study

Gastric insufflation and surgical view according to mask ventilation method for laparoscopic cholecystectomy: a randomized controlled study

BACKGROUND

Proper mask ventilation is important to prevent air inflow into the stomach during induction of general anesthesia, and it is difficult to send airflow only through the trachea without gastric inflation. Changes in gastric insufflation according to mask ventilation during anesthesia induction were compared.

METHODS

In this prospective, randomized, single-blind study, 230 patients were analyzed to a facemask-ventilated group (Ventilation group) or no-ventilation group (Apnea group) during anesthesia induction. After loss of consciousness, pressure-controlled ventilation at an inspiratory pressure of 15 cmH2O was performed for two minutes with a two-handed mask-hold technique for Ventilation group. For Apnea group, only the facemask was fitted to the face for one minute with no ventilation. Next, endotracheal intubation was performed. The gastric cross-sectional area (CSA, cm2) was measured using ultrasound before and after induction. After pneumoperitoneum with carbon dioxide, gastric insufflation of the surgical view was graded by the surgeon for each group.

RESULTS

Increase of postinduction antral CSA on ultrasound were not significantly different between Ventilation group and Apnea group (0.04 ± 0.3 and 0.02 ± 0.28, p-value = 0.225). Additionally, there were no significant differences between the two groups in surgical grade according to surgeon's judgement.

CONCLUSIONS

Pressure-controlled ventilation at an inspiratory pressure of 15 cmH2O for two minutes did not increase gastric antral CSA and insufflation of stomach by laparoscopic view.

TRIAL REGISTRATION

http://cris.nih.go.kr (KCT0003620) on 13/3/2019.

Effect of facemask oxygenation with and without positive pressure ventilation on gastric volume during anesthesia induction in patients undergoing laparoscopic cholecystectomy or partial hepatectomy: a randomized controlled trial

BACKGROUND

Studies focusing on the relationship between gastric volume and facemask oxygenation without ventilation during apnea in anesthesia induction are scarce. This study compared the change in gastric volume during apnea in anesthesia induction using facemask ventilation and facemask oxygenation without ventilation in adults undergoing laparoscopic surgery.

METHODS

In this prospective, randomized, double-blinded trial, 70 adults undergoing laparoscopic surgery under general anesthesia were divided into two groups to receive facemask oxygenation with and without ventilation for 60 seconds after loss of consciousness. Before anesthesia induction and after endotracheal intubation, the gastric antral cross-sectional area was measured with ultrasound imaging. Arterial blood gases were tested at baseline (T1), after preoxygenation (T2), after loss of consciousness (T3), and before and after endotracheal intubation (T4 and T5, respectively).

RESULTS

Sixty patients were included (ventilation n = 30; non ventilation n = 30, 10 patients were excluded). The median [IQR] change of gastric antral cross-sectional area in ventilation group was significantly higher than in non ventilation group (0.83 [0.20 to 1.54] vs. 0.10 [- 0.11 to 0.56] cm₂, P = 0.001). At T4 and T5, the PaO₂ in ventilation group was significantly higher than in non ventilation group (T4: 391.83 ± 61.53 vs. 336.23 ± 74.99 mmHg, P < 0.01; T5: 364.00 ± 58.65 vs. 297.13 ± 86.95 mmHg, P < 0.01), while the PaCO₂ in non ventilation group was significantly higher (T4: 46.57 ± 5.78 vs. 37.27 ± 6.10 mmHg, P < 0.01; T5: 48.77 ± 6.59 vs. 42.63 ± 6.03 mmHg, P < 0.01) and the pH value in non ventilation group was significantly lower (T4: 7.35 ± 0.029 vs 7.42 ± 0.047, P < 0.01; T5: 7.34 ± 0.033 vs 7.39 ± 0.044, P < 0.01). At T4, the HCO₃^- in non ventilation group was significantly higher (25.79 ± 2.36 vs. 23.98 ± 2.18 mmol l^- 1, P < 0.01).

CONCLUSIONS

During apnoea, the increase in gastric volume was milder in patients undergoing facemask oxygenation without ventilation than with positive pressure ventilation.

TRIAL REGISTRATION

ChiCTR2100054193, 10/12/2021, Title: "Effect of positive pressure and non-positive pressure ventilation on gastric volume during induction of general anesthesia in laparoscopic surgery: a randomized controlled trial". Website: https://www.chictr.ogr.cn .

Ultrasound-guided esophageal compression during mask ventilation in small children: a prospective observational study

Background

The use of cricoid compression to prevent insufflation remains controversial, and its use in children is limited. This study aimed to examine the effect of real-time ultrasound-guided esophageal compression on the prevention of gastric insufflation.

Method

This prospective observational study was conducted with fifty children aged < 2 years undergoing general anesthesia. Patients were excluded if they were at an increased risk for gastric regurgitation or pulmonary aspiration. Following anesthetic induction under spontaneous breathing, ultrasound-guided esophageal compression was performed during pressure-controlled face-mask ventilation using a gradual increase in peak inspiratory pressure from 10 to 24 cm H₂O to determine the pressure at which gastric insufflation occurred. The primary outcome was the incidence of gastric insufflation during anesthetic induction with variable peak inspiratory pressure after real-time ultrasound-guided esophageal compression was applied.

Results

Data from a total of 42 patients were analyzed. Gastric insufflation was observed in 2 (4.7%) patients. All patients except one had their esophagus on the left side of the trachea. Applying ultrasound-guided esophageal compression did not affect the percentage of glottic opening scores (P = 0.220).

Conclusions

The use of real-time ultrasound-guided esophageal compression pressure can aid preventing gastric insufflation during face-mask ventilation in children less than 2 years old.

Trial registration

Clinicaltrials.gov identifier: NCT04645043.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12871-022-01803-5.

Continuous positive airway pressure to reduce the risk of early peripheral oxygen desaturation after onset of apnoea in children: A double-blind randomised controlled trial

Continuous positive airway pressure (CPAP) during anaesthesia induction improves oxygen saturation (SpO₂) outcomes in adults subjected to airway manipulation, and could similarly support oxygenation in children. We evaluated whether CPAP ventilation and passive CPAP oxygenation in children would defer a SpO₂ decrease to 95% after apnoea onset compared to the regular technique in which no positive airway pressure is applied. In this double-blind, parallel, randomised controlled clinical trial, 68 children aged 2–6 years with ASA I–II who underwent surgery under general anaesthesia were divided into CPAP and control groups (n = 34 in each group). The intervention was CPAP ventilation and passive CPAP oxygenation using an anaesthesia workstation. The primary outcome was the elapsed time until SpO₂ decreased to 95% during a follow-up period of 300 s from apnoea onset (T1). We also recorded the time required to regain baseline levels from an SpO₂ of 95% aided by positive pressure ventilation (T2). The median T1 was 278 s (95% confidence interval [CI]: 188–368) in the CPAP group and 124 s (95% CI: 92–157) in the control group (median difference: 154 s; 95% CI: 58–249; p = 0.002). There were 17 (50%) and 32 (94.1%) primary events in the CPAP and control groups, respectively. The hazard ratio was 0.26 (95% CI: 0.14–0.48; p<0.001). The median for T2 was 21 s (95% CI: 13–29) and 29 s (95% CI: 22–36) in the CPAP and control groups, respectively (median difference: 8 s; 95% CI: -3 to 19; p = 0.142). SpO₂ was significantly higher in the CPAP group than in the control group throughout the consecutive measures between 60 and 210 s (with p ranging from 0.047 to <0.001). Thus, in the age groups examined, CPAP ventilation and passive CPAP oxygenation deferred SpO₂ decrease after apnoea onset compared to the regular technique with no positive airway pressure.

Effect of positive end-expiratory pressure during anaesthesia induction on non-hypoxic apnoea time in infants: A randomised controlled trial

BACKGROUND

Hypoxaemia occurs frequently in infants during anaesthetic induction.

OBJECTIVE

We evaluated the effect of positive end-expiratory pressure during anaesthesia induction on nonhypoxic apnoea time in infants.

DESIGN

Randomised controlled trial.

SETTING

Tertiary care children's hospital, single centre, from November 2018 to October 2019.

PATIENTS

We included patients under 1 year of age receiving general anaesthesia.

INTERVENTION

We assigned infants to a 7 cmH2O or 0 cmH2O positive end-expiratory pressure group. Anaesthesia was induced with 0.02 mg kg-1 atropine, 5 mg kg-1 thiopental sodium and 3 to 5% sevoflurane, and neuromuscular blockade with 0.6 mg kg-1 rocuronium. Thereafter, 100% oxygen was provided via face mask with volume-controlled ventilation of 6 ml kg-1 tidal volume, and either 7 cmH2O or no positive end-expiratory pressure. After 3 min of ventilation, the infants' trachea was intubated but disconnected from the breathing circuit, and ventilation resumed when pulse oximetry reached 95%.

MAIN OUTCOME MEASURE

The primary outcome was nonhypoxic apnoea time defined as the time from cessation of ventilation to a pulse oximeter reading of 95%, whereas the secondary outcome was the incidence of significant atelectasis (consolidation score ≥2) assessed by lung ultrasound.

RESULTS

Sixty patients were included in the final analysis. Apnoea time in the 7 cmH2O positive end-expiratory pressure group (105.2 s) increased compared with that in the control group (92.1 s) (P = 0.011, mean difference 13.0 s, 95% CI, 3.1 to 22.9 s). Significant atelectasis was observed in all patients without positive end-expiratory pressure and 66.7% of those with 7 cmH2O positive end-expiratory pressure (P = 0.019, 95% CI, 1.7 to 563.1, odds ratio 31.2).

CONCLUSION

Positive end-expiratory pressure during anaesthesia induction with face mask ventilation increased nonhypoxic apnoea time in infants.

CLINICAL TRIAL REGISTRATION

www.clinicaltrials.gov, NCT03540940.

Effect of facemask ventilation with different ventilating volumes on gastric insufflation during anesthesia induction in patients undergoing laparoscopic cholecystectomy

Objectives:

To compare the occurrence of gastric insufflation during anesthesia induction in patients undergoing laparoscopic cholecystectomy, using facemask ventilation with different ventilation volumes.

Methods:

This is a prospective study of 54 patients undergoing laparoscopic cholecystectomy under general anesthesia between January 2018 and June 2018. Facemask ventilation with volume mode controlled at 6 ml/kg (group V6), 8 ml/kg (group V8) or 10 ml/kg (group V10) was applied for 120 seconds (sec) during anesthesia induction. Before facemask ventilation and at 120 sec of facemask ventilation, gastric insufflation was determined by ultrasonography. Gastric insufflation was also evaluated using direct vision of laparoscopy. Respiratory parameters were monitored.

Results:

The incidence of gastric insufflation in group V10 (55.6%) was significantly higher than that in groups V6 (11.1%) and V8 (16.7%). However, it showed no significant difference between groups V6 and V8. During facemask ventilation for 120 sec, carbon dioxide accumulation trend occurred in group V6, and group V10 exhibited evidence of hyper-ventilation. Group V8 might be considered the best balance between low gastric insufflation and effective lung ventilation.

Conclusion:

Facemask ventilation with a ventilation volume of 8 ml/kg seems to have adequate preoxygenation and avoid excessive gastric insufflation during anesthesia induction in laparoscopic cholecystectomy.

Effect of gastric decompression on postoperative vomiting in pediatric patients undergoing strabismus surgery: a randomized controlled study

Background

Postoperative vomiting (POV) is one of the most serious complications in pediatric patients undergoing strabismus surgery. This study was conducted to test the hypothesis that gastric decompression (GD) could prevent POV caused by gastric distension after mask ventilation.

Methods

A total of 60 pediatric patients (ASA PS I-II, aged one to 10 years) were randomly allocated to two groups; Group D (n = 30) and Group C (n = 30). Induction of anesthesia was performed with careful face mask ventilation with 100% O₂ (3 L/min) and sevoflurane 3 vol% to limit airway pressure below 20 cmH₂O. Endotracheal intubation was done after confirming adequate neuromuscular blockade. Then, the patients in Group D received GD, while patients in Group C did not. After the surgery, POV was assessed during the emergence from anesthesia in the operating room and postanesthetic care unit (30 min and 60 min).

Results

During the emergence, POV was significantly decreased in Group D compared to Group C (Group D 3.3% vs. Group C 30.0%, P = 0.006). The odds ratio analysis showed a lower incidence of POV in Group D (odds ratio = 0.080; 95% confidence limit: 0.009-0.685) during the emergence period. There was no significant difference in the incidence of POV in the postanesthetic care unit (Group D 6.7% vs. Group C 4.3% at 30 min, P = 1.000; 0% in both groups at 60 min).

Conclusions

GD reduced the incidence of POV in pediatric patients undergoing strabismus surgery during emergence.

Manual vs pressure-controlled facemask ventilation during the induction of general anesthesia in children: A prospective randomized controlled study

BACKGROUND

Gastric insufflation frequently occurs during facemask ventilation in children. In the present study, we compared the incidence of gastric insufflation between pressure-controlled facemask ventilation and manual facemask ventilation during general anesthesia induction in children.

METHODS

Children in the pressure-controlled ventilation group (n = 76) received pressure-controlled facemask ventilation at an inspiratory pressure of 13 cm H₂ O. In the manual ventilation group (n = 75), facemask ventilation was manually performed by anesthesiologists, who tried to maintain an inspiratory pressure of 13 cm H₂ O. The adjustable pressure limiting valve was set at 13 cm H₂ O. The incidence of gastric insufflation during 90 seconds after the initiation of ventilation was assessed using epigastric auscultation and gastric ultrasonography.

RESULTS

The incidence of gastric insufflation was significantly higher in the manual  facemask ventilation group than in the pressure-controlled ventilation group (48% vs 12%, respectively; odds ratio 7.78, 95% confidence interval [CI] 3.38-17.9; P < 0.001). The mean peak airway pressure during ventilation was significantly higher in the manual ventilation group than in the pressure-controlled ventilation group (16.1 [3.0] cm H₂ O vs 13.0 [0.1] cm H₂ O; 95% CI of differences, 2.36-3.71 cm H₂ O; P < 0.001). The manual ventilation group exhibited a wide peak airway pressure  range (11-26 cm H₂ O) and a wide variation of tidal volume (0-7.0 mL/kg) compared with those of the pressure-controlled ventilation group (13-14 cm H₂ O and 0.6-16.0 mL/kg, respectively).

CONCLUSION

At an inspiratory pressure of 13 cm H₂ O, pressure-controlled ventilation may be more effective than manual ventilation in preventing gastric insufflation while providing stable ventilation in children.