Device capable of reducing gastric inflation during artificial ventilation in a manikin model.

Gastric inflation is a significant issue when ventilation is performed in cases of unprotected airway. The objective of this study was to compare the amounts of gastric insufflation and tidal volumes produced by a hose-extended bag-valve-mask (BVM) device supplemented by an interposed reservoir bag with a similar BVM without the reservoir in a simulated human model. Fourteen academic dental staff members performed 10 ventilations on a manikin using the reservoir-supplemented device in comparison to the control BVM in a randomized order. Lung compliance was adjusted to 45 (high) and 4.5 mL/mbar (low), and the lower esophageal sphincter pressure (LOSP) simulator to a pressure of 15 and 3 mbar, respectively, in different settings. Lower tidal volumes were observed with the new device than with the control BVM at high compliance with LOSP of 15 mbar (median 506 vs. 787 mL, respectively; p = 0.0002) and LOSP of 3 mbar (median 544 vs. 794 mL, respectively; p = 0.0006), as well as during ventilation at low lung compliance and LOSP of 3mbar (median 131 vs. 163 mL, respectively; p = 0.0342). No differences were detected at low lung compliance and LOSP of 15 mbar (median 175 vs. 194 mL; p = 0.3804). Gastric inflation almost exclusively occurred in case of low lung compliance, being markedly lower with the new device than with the control device at 15 mbar LOSP (300 vs. 2225 mL, respectively; p = 0.0006), and at 3 mbar LOSP (1138 vs. 3050 mL, respectively; p = 0.0001). Application of the hose-extended bag-valve-mask device supplemented with a reservoir bag reduces tidal volumes. Marked reduction of gastric inflation by use of this device becomes effective under conditions with low lung compliance.

Alternative concept of ventilation during cardiopulmonary resuscitation (CPR) in dental chairs.

Infrequent training of artificial ventilation in dental facilities implies poor performance of this procedure under CPR. Gastric inflation is a significant issue when ventilation is performed on an unprotected airway. An Easy Grip (EG) Bag-Valve-Mask Resuscitator, a Laryngeal Tube (LT), size #5, and a SMART BAG (SB) resuscitator, a pressure-limiting device, were tested to assess the respiratory effects especially focussing on prevention of gastric inflation during simulated CPR. Twenty academic dental staff members performed ten ventilations on a manikin during CPR by use of EG, LT and SB in a randomized order. In twelve experiments the oesophageal sphincter pressure was adjusted to 15 mbar (best case), in eight experiments to 0 mbar (worst case scenario). Best case scenario median tidal volume distributions achieved by EG (median 144 ml) and LT (75 ml) did not differ, whereas differences were found between EG and SB (31 ml; p = 0.055) as well as between SB and LT (p = 0.042). None of the values met recommended ranges. Almost no gastric inflation occurred. Worst case scenario ventilation by use of the LT resulted in profoundly lower median gastric inflation volumes (median 13 ml) compared to SB (median 288 ml; p=0.008) and EG (800 ml; p = 0.008). Median tidal volume distributions also differed between LT (225 ml) vs EG (100 ml) (p=0.016) and LT vs SB (19 ml) (p =0.008). Chest compression was delayed in ten experiments by LT insertion for 28 s (median). In a later stage of CPR or in case of mask ventilation difficulties, the LT may serve as a helpful tool in dental facilities. CPR training must focus on the importance of chest compression which must not be discontinued if an LT is inserted. The SB might gain value if higher tidal volumes are achieved, exerting a higher risk of gastric inflation.

Evidence for left ventricular remodeling after percutaneous coronary intervention: effect of percutaneous coronary intervention on left ventricular ejection fraction and volumes.

BACKGROUND: Post-stress ejection fraction (EF), end-diastolic (EDV) and end-systolic (ESV) volumes by gated myocardial perfusion SPECT (MPS) are well validated, reproducible and of prognostic significance. However, little is known about the impact of percutaneous coronary intervention (PCI) on left ventricular volumes and remodeling. METHODS: Thirty-eight patients who underwent MPS before and 6 months after PCI were evaluated. MPS were interpreted deriving summed stress (SSS), rest (SRS) and difference (SDS = SSS-SRS; extent of ischemia) scores. EF, EDV and ESV were generated by QGS trade mark. Pre-PCI MPS were compared to post-PCI MPS. RESULTS: Single vessel disease was present in 63% of patients. PCI of one vessel was performed in 82% of patients. After 6 months, SSS (10.6 +/- 6.3 vs. 2.8 +/- 4.3, p < 0.001) and SDS (8.2 +/- 5.6 vs. 1.4 +/- 2.3, p < 0.001) had improved; however, EF did not change significantly (55 +/- 10 vs. 57 +/- 13, p = ns). Still, EDV (105 +/- 25 ml vs. 96 +/- 25 ml, p = 0.006) and ESV (49 +/- 19 ml vs. 41 +/- 18 ml, p = 0.001) were significantly reduced. CONCLUSION: Results of MPS documented the beneficial effect of PCI on symptoms and extent of ischemia. In addition, the findings showed a significant decrease in ESV and EDV after PCI as compared to pre-PCI findings which points to a positive effect on left ventricular remodeling even in the absence of significant changes in EF.