Definition and research guide
This page combines a MeSH definition, publication statistics and selected research abstracts. It is a starting point for reading the literature, not a medical textbook or a systematic evidence review.
Content available: 4 complete abstracts (914 words), 10 references. Full article text is not stored or reproduced here; follow the PMID, DOI or PMC links to read the original sources and their access terms.
Definition
The cartilaginous and membranous tube descending from the larynx and branching into the right and left main bronchi.
Definition: NLM Medical Subject Headings (MeSH) scope note (Public domain (U.S. National Library of Medicine); attribution requested). View the MeSH record.
Also known as: Tracheas.
Where it fits in the MeSH classification
- Broader topics
- Respiratory System
- See also
- Anesthesia, Endotracheal; Intubation, Intratracheal; Tracheostomy; Tracheotomy
Research landscape
PubMed indexes 40,006 records tagged with the MeSH heading “Trachea” (counts retrieved 2026-10-31). 3,437 of them (8.6%) were published from 2020 onward, and the busiest period so far is through 1999 with 23,287 records.
Reviews account for 1,948 records (4.9%) and meta-analyses for 46. Randomized controlled trials number 393 (1.0%) as a share of all records on the topic. Randomized trials make up only a small share of this literature, so much of what is known comes from laboratory, observational or descriptive work.
Show the data
| Period | Records |
|---|---|
| through 1999 | 23,287 |
| 2000-2009 | 6,737 |
| 2010-2019 | 6,545 |
| 2020 onward | 3,437 |
Publication-type chart data
| Type | Records | Share |
|---|---|---|
| Reviews | 1,948 | 4.9% |
| Meta-analyses | 46 | 0.1% |
| Randomized controlled trials | 393 | 1.0% |
Method: PubMed query "Trachea"[MeSH Terms] with publication-type and date filters, retrieved 2026-10-31.
Reading the evidence in anatomy and physiology
Anatomy describes how body structures are built and physiology describes how they normally work, so most findings here are descriptive or mechanistic rather than evidence about treatment. Much of what is known comes from dissection, imaging, tissue studies and experiments in animals, and measurements in healthy volunteers can differ from those in people with disease or at different ages. Normal ranges vary between individuals and populations. Check whether a result was measured in people or in another species, the age and health of the participants, and the method used.
Evidence from open-access studies
These open-access studies come from PubMed’s best-match results for this heading (papers whose main topic it is), ranked here by citation count, with one recent addition. Each abstract is reproduced in full under its recorded open licence so that you can read the authors’ own words. They illustrate the literature; they are not a systematic summary of it. Citation counts measure attention, not reliability or clinical benefit.
| Study / authors | Year | Source label / design | Europe PMC citations | Licence / source |
|---|---|---|---|---|
| Randomized Trial of Fetal Surgery for Severe Left Diaphragmatic Hernia | 2021 | Randomized controlled trial Design not recorded in structured metadata | 289 | cc by PMID 34106556 · DOI · PMC7613453 |
| High-precision targeting workflow for volume electron microscopy | 2021 | Research article Design not recorded in structured metadata | 47 | cc by PMID 34160561 · DOI · PMC8225610 |
| The sex of organ geometry | 2024 | Research article Design not recorded in structured metadata | 26 | cc by PMID 38811741 · DOI · PMC11168936 |
| Segmental Tracheal Resection for Thyroid Cancer: Perioperative Morbidity, Locoregional Control, and Survival | 2026 | Research article Design not recorded in structured metadata | 2 | cc by PMID 41059669 · DOI · PMC12891758 |
Randomized Trial of Fetal Surgery for Severe Left Diaphragmatic Hernia [1]
Abstract reading summary — source excerpts
- Opening excerpt
- BackgroundObservational studies have shown that fetoscopic endoluminal tracheal occlusion (FETO) has been associated with increased survival among infants with severe pulmonary hypoplasia due to isolated congenital diaphragmatic hernia on the left side, but data from randomized trials are lacking.
- Closing excerpt
- ).
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (400 words)
BackgroundObservational studies have shown that fetoscopic endoluminal tracheal occlusion (FETO) has been associated with increased survival among infants with severe pulmonary hypoplasia due to isolated congenital diaphragmatic hernia on the left side, but data from randomized trials are lacking.MethodsIn this open-label trial conducted at centers with experience in FETO and other types of prenatal surgery, we randomly assigned, in a 1:1 ratio, women carrying singleton fetuses with severe isolated congenital diaphragmatic hernia on the left side to FETO at 27 to 29 weeks of gestation or expectant care. Both treatments were followed by standardized postnatal care. The primary outcome was infant survival to discharge from the neonatal intensive care unit. We used a group-sequential design with five prespecified interim analyses for superiority, with a maximum sample size of 116 women.ResultsThe trial was stopped early for efficacy after the third interim analysis. In an intention-to-treat analysis that included 80 women, 40% of infants (16 of 40) in the FETO group survived to discharge, as compared with 15% (6 of 40) in the expectant care group (relative risk, 2.67; 95% confidence interval [CI], 1.22 to 6.11; two-sided P = 0.009). Survival to 6 months of age was identical to the survival to discharge (relative risk, 2.67; 95% CI, 1.22 to 6.11). The incidence of preterm, prelabor rupture of membranes was higher among women in the FETO group than among those in the expectant care group (47% vs. 11%; relative risk, 4.51; 95% CI, 1.83 to 11.9), as was the incidence of preterm birth (75% vs. 29%; relative risk, 2.59; 95% CI, 1.59 to 4.52). One neonatal death occurred after emergency delivery for placental laceration from fetoscopic balloon removal, and one neonatal death occurred because of failed balloon removal. In an analysis that included 11 additional participants with data that were available after the trial was stopped, survival to discharge was 36% among infants in the FETO group and 14% among those in the expectant care group (relative risk, 2.65; 95% CI, 1.21 to 6.09).ConclusionsIn fetuses with isolated severe congenital diaphragmatic hernia on the left side, FETO performed at 27 to 29 weeks of gestation resulted in a significant benefit over expectant care with respect to survival to discharge, and this benefit was sustained to 6 months of age. FETO increased the risks of preterm, prelabor rupture of membranes and preterm birth. (Funded by the European Commission and others; TOTAL ClinicalTrials.gov number, NCT01240057.).
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 34106556 · DOI · PMC7613453
High-precision targeting workflow for volume electron microscopy [2]
Abstract reading summary — source excerpts
- Opening excerpt
- Cells are 3D objects.
- Closing excerpt
- Using this method, we acquired volumes of specific single cells within large tissues such as 3D cultures of mouse mammary gland organoids, tracheal terminal cells in Drosophila melanogaster larvae, and ovarian follicular cells in adult Drosophila, discovering ultrastructural details that could not be appreciated before.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (156 words)
Cells are 3D objects. Therefore, volume EM (vEM) is often crucial for correct interpretation of ultrastructural data. Today, scanning EM (SEM) methods such as focused ion beam (FIB)-SEM are frequently used for vEM analyses. While they allow automated data acquisition, precise targeting of volumes of interest within a large sample remains challenging. Here, we provide a workflow to target FIB-SEM acquisition of fluorescently labeled cells or subcellular structures with micrometer precision. The strategy relies on fluorescence preservation during sample preparation and targeted trimming guided by confocal maps of the fluorescence signal in the resin block. Laser branding is used to create landmarks on the block surface to position the FIB-SEM acquisition. Using this method, we acquired volumes of specific single cells within large tissues such as 3D cultures of mouse mammary gland organoids, tracheal terminal cells in Drosophila melanogaster larvae, and ovarian follicular cells in adult Drosophila, discovering ultrastructural details that could not be appreciated before.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 34160561 · DOI · PMC8225610
The sex of organ geometry [3]
Abstract reading summary — source excerpts
- Opening excerpt
- Organs have a distinctive yet often overlooked spatial arrangement in the body1-5.
- Closing excerpt
- Interorgan geometry represents a previously unrecognized level of biological complexity which might enable or confine communication across organs and could help explain sex or species differences in organ function.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (194 words)
Organs have a distinctive yet often overlooked spatial arrangement in the body1-5. We propose that there is a logic to the shape of an organ and its proximity to its neighbours. Here, by using volumetric scans of many Drosophila melanogaster flies, we develop methods to quantify three-dimensional features of organ shape, position and interindividual variability. We find that both the shapes of organs and their relative arrangement are consistent yet differ between the sexes, and identify unexpected interorgan adjacencies and left-right organ asymmetries. Focusing on the intestine, which traverses the entire body, we investigate how sex differences in three-dimensional organ geometry arise. The configuration of the adult intestine is only partially determined by physical constraints imposed by adjacent organs; its sex-specific shape is actively maintained by mechanochemical crosstalk between gut muscles and vascular-like trachea. Indeed, sex-biased expression of a muscle-derived fibroblast growth factor-like ligand renders trachea sexually dimorphic. In turn, tracheal branches hold gut loops together into a male or female shape, with physiological consequences. Interorgan geometry represents a previously unrecognized level of biological complexity which might enable or confine communication across organs and could help explain sex or species differences in organ function.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 38811741 · DOI · PMC11168936
Segmental Tracheal Resection for Thyroid Cancer: Perioperative Morbidity, Locoregional Control, and Survival [4]
Abstract reading summary — source excerpts
- Opening excerpt
- BackgroundSegmental tracheal resection is rarely needed for advanced thyroid cancer but is among the most complex, high-risk thyroid surgeries.
- Closing excerpt
- ConclusionsSegmental tracheal resection for advanced thyroid cancer is technically complex and high-risk, but most patients stay recurrence-free 5 years post-surgery.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (164 words)
BackgroundSegmental tracheal resection is rarely needed for advanced thyroid cancer but is among the most complex, high-risk thyroid surgeries.MethodsRetrospective study of patients undergoing segmental tracheal resection for thyroid cancer at MD Anderson Cancer Center (2005-2024).ResultsWe identified 120 patients with a median follow-up of 4.6 years (range 0.02-16.38). Papillary thyroid cancer was most common (68%). The median number of tracheal rings resected was 4 (range 1-9). Seventeen (14%) patients had a new tracheostomy placed at the time of surgery, with 11 (9%) remaining trach-dependent at last follow-up. Twenty-six (22%) patients had a return to the operating room within 30 days, while 3 (3%) patients suffered perioperative mortality. The more common postoperative complications included tracheostomy tube placement (10%), hematoma (7%), and anastomotic air leak (6%). Median hospitalization was 6 days (range 2-67). Locoregional control (LRC) and overall survival (OS) were 79% and 77% at 5 years, respectively.ConclusionsSegmental tracheal resection for advanced thyroid cancer is technically complex and high-risk, but most patients stay recurrence-free 5 years post-surgery.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 41059669 · DOI · PMC12891758
Key reviews and meta-analyses
The most cited review-type papers among PubMed’s best-match results for this heading, listed with bibliographic details only. Follow the links for the full text and access terms.
- Research article The microbiome of the upper respiratory tract in health and disease [5]
- Research article 3D bioprinted silk fibroin hydrogels for tissue engineering [6]
- Research article Branching morphogenesis [7]
- Research article Tracheal branching morphogenesis in Drosophila: new insights into cell behaviour and organ architecture [8]
- Research article Notch signaling in the mammalian respiratory system, specifically the trachea and lungs, in development, homeostasis, regeneration, and disease [9]
- Research article Tracheal replacement [10]
References
- Deprest JA, Nicolaides KH, Benachi A, Gratacos E, Ryan G, Persico N, et al.. Randomized Trial of Fetal Surgery for Severe Left Diaphragmatic Hernia. . 2021. PMID 34106556 · DOI · PMC7613453
- Ronchi P, Mizzon G, Machado P, D'Imprima E, Best BT, Cassella L, et al.. High-precision targeting workflow for volume electron microscopy. . 2021. PMID 34160561 · DOI · PMC8225610
- Blackie L, Gaspar P, Mosleh S, Lushchak O, Kong L, Jin Y, et al.. The sex of organ geometry. . 2024. PMID 38811741 · DOI · PMC11168936
- Maniakas A, Wilde DC, Fournier I, Hyde EK, Xu L, Wang JR, et al.. Segmental Tracheal Resection for Thyroid Cancer: Perioperative Morbidity, Locoregional Control, and Survival. . 2026. PMID 41059669 · DOI · PMC12891758
- Kumpitsch C, Koskinen K, Schöpf V, Moissl-Eichinger C. The microbiome of the upper respiratory tract in health and disease. BMC Biol. 2019. PMID 31699101 · DOI · PMC6836414
- Kim SH, Hong H, Ajiteru O, Sultan MT, Lee YJ, Lee JS, et al.. 3D bioprinted silk fibroin hydrogels for tissue engineering. Nat Protoc. 2021. PMID 34716451 · DOI
- Horowitz A, Simons M. Branching morphogenesis. Circ Res. 2008. PMID 18845818 · DOI
- Affolter M, Caussinus E. Tracheal branching morphogenesis in Drosophila: new insights into cell behaviour and organ architecture. Development. 2008. PMID 18480161 · DOI
- Kiyokawa H, Morimoto M. Notch signaling in the mammalian respiratory system, specifically the trachea and lungs, in development, homeostasis, regeneration, and disease. Dev Growth Differ. 2020. PMID 31613406 · DOI · PMC7028093
- Etienne H, Fabre D, Gomez Caro A, Kolb F, Mussot S, Mercier O, et al.. Tracheal replacement. Eur Respir J. 2018. PMID 29444919 · DOI
About this article
- Sources
- NLM Medical Subject Headings (definition, synonyms); NCBI PubMed (counts, identifiers); Europe PMC (open-access abstracts and citation counts).
- Verification
- Every reference was resolved against PubMed on 2026-10-31; title, year and DOI matched.
- Review state
- automated source verified; no human expert review has been recorded yet.
- Version
- 1, last updated 2026-10-31.
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Evidence strength
EvidenceHelix's computed view of the study designs behind this topic: how common meta-analyses, randomized trials and reviews are, how recent the literature is, and a plain-language reading. It describes the design mix of the literature. It is not a quality appraisal of any study, and it is not medical advice.