ABSTRACT

Study objective To systematically review the literature regarding the presence of sublingual microcirculatory alterations during the immediate and early postoperative period.

Design Systematic review and meta-analysis searching PubMed, Scopus, and Google Scholar.

Patients/interventions Studies comparing sublingual microcirculation before and after surgery.

Measurement The primary outcome was to investigate the severity of microcirculatory alterations during the immediate and early postoperative period in adult patients undergoing non-cardiac and cardiac surgery.

Main results Among 17 eligible studies, 13 were finally analyzed. A non-statistically significant difference was found between preoperative and postoperative total vessel density (p=0.084; estimate: −0.029; 95% CI: −0.31 to 0.26; I2 = 22.55%, Q = 10.23, p=0.24). Perfused vessel density significantly decreased postoperatively (p=0.035; estimate: 0.344; 95% CI: 0.02 to 0.66; I2 = 65.66%, Q = 41.77, p<0.001), while perfused boundary region significantly increased postoperatively (p=0.031; estimate: −0.415; 95% CI: −0.79 to −0.03; I2 = 37.21%, Q = 6.56, p=0.16). Microvascular flow index significantly decreased postoperatively (p=0.028; estimate: 0. 587; 95% CI: 0.06 to 1.11; I2 = 86.09%, Q = 96.28, p<0.001), while a non-statistically significant difference was found between preoperative and postoperative proportion of perfused vessels (p=0.089; estimate: 0.53; 95% CI: −0.08 to 1.14; I2 = 70.71%, Q = 18.99, p=0.002). The results in the non-cardiac surgery subgroup were comparable with the full group except that a statistically non-significant difference in PVD was found in the remaining seven studies (p=0.19; estimate: 0.26; 95% CI: −0.13 to 0.66; I2 = 71.94%, Q = 33.42, p=0.002). The other parameters did not differ significantly from their respective full group results.

Conclusions Significant sublingual microcirculatory alterations are present during the immediate and early postoperative period.

Competing Interest Statement

The authors have declared no competing interest.

Funding Statement

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Author Declarations

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

Yes

The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

Non-applicable

All necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived.

Yes

I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).

Yes

I have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable.

Yes

Footnotes

Disclosures

Declarations of interest: None.

Funding: This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Data Availability

Data can be made available upon request through a collaborative process. Please contact thanoschalkias@yahoo.gr for additional information.

LIST OF ABBREVIATIONSICUintensive care unitIDFincident dark-fieldMFImicrovascular flow indexPBRperfused boundary regionPPVproportion of perfused vesselsPVDperfused vessel densitySDFsidestream dark-fieldSMDstandardized mean differencesTVDtotal vessel density