A fast detection method to analyze gaseous organic compounds in complex gas mixtures was developed, using a needle trap device (NTD) in conjunction with thermal-desorption photoionization time-of-flight mass spectrometry (TD-PI-TOFMS). The mass spectrometer was coupled via a deactivated fused silica capillary to an injector of a gas chromatograph. In the hot injector the analytes collected on the NTD were thermally desorbed and directly transferred to the PI-TOFMS ion source. The molecules are softly ionized either by single photon ionization (SPI, 118 nm) or by resonance enhanced multiphoton ionization (REMPI, 266 nm) and the molecular ion signals are detected in the TOF mass analyzer. Analyte desorption and subsequent PI-TOFMS detection step only lasts ten seconds. The specific selectivity of REMPI (i.e. aromatic compounds) and universal ionization characteristics render PI-MS as a promising detection system. As a first, demonstrative application alveolar-phase breath gas of healthy, non-smoking subjects was sampled on NTDs. While smaller organic compounds as acetone, acetaldehyde, isoprene or cysteamine can be detected in the breath gas with SPI, REMPI depicts the aromatic substances phenol and indole at 266 nm. In breath gas of a healthy, smoking male subject, several xenobiotic substances such as benzene, toluene, styrene and ethylbenzene can be found as well. Furthermore, the NTD-REMPI-TOFMS setup was tested for breath gas taken from a mechanically ventilated pig under continuous intravenous propofol (2,6-diisopropylphenol, narcotic drug) infusion.