Carbon dioxide levels of ventilated adult critically ill post-operative patients on arrival at the intensive care unit.

Abstract

Background: The transportation of critically ill patients presents a precarious situation in which adverse events may occur. At Chris Hani Baragwanath Academic Hospital (CHBAH) patients were manually ventilated using a manual resuscitator bag during transportation from theatre to the intensive care unit (ICU).

Objectives: To evaluate the arterial partial pressure of carbon dioxide (PaCO₂ ) levels of ventilated adult critically ill post-operative patients on arrival at the ICU at CHBAH.

Methods: This was a cross-sectional study using convenience sampling. Pre- and post-transportation arterial blood gases were obtained from 47 patients.

Results: There was a statistically significant difference in the pre- and post-transport PaCO₂ level (p=0.03), with a mean difference of 3.3 mmHg. The pre- and post-transport arterial partial pressure of oxygen (PaO₂ ) level (p≤0.001) and the week and weekend pre-transport (p≤0.001) and post-transport (p=0.01) PaCO₂ were statistically significantly different. No statistically significant difference was found in the other arterial blood gas parameters or in the post-transport PaCO₂ of those patients (26 (55.3%)), who received a neuromuscular blocking drug compared with those that did not. Adverse events were noted during 12 (25.6%) of the transports, 5 (41.7%) of which were patient-related, and 7 (58.3%) of which were infrastructure-related.

Conclusion: There was a statistically but not clinically significant difference in the pre- and post-transport PaCO₂ level and between week and weekend transportations. Hypercarbia was the most common derangement in all transports. Adverse events occurred during one-quarter of transportations.

Contributions of the study: This study evaluated the PaCO₂ levels of critically ill patients at CHBAH during transportation from theatre to the ICU. The findings indicate that manual ventilation was not injurious. The authors recommend reproducing the study in patients with severe ARDS and pulmonary hypertension to ascertain if manual ventilation is safe in this population; and also with healthcare practitioners other than anaesthesiologists, who may not be as experienced in manual ventilation.