Aspiration biopsies: a good diagnostic tool

Aspiration biopsies were introduced for the diagnosis of human malignancies in the 1930s. Because of the high degree of safety of the transcutaneous aspirations, virtually every organ in the body has become a target for this procedure. The advantages are: 1. It is an office procedure readily accepted by the patient. 2. There is no interference with further therapeutic procedures. 3. There is not sufficient trauma to produce haemorrhage of dissemination of the tumour. The simple instruments required are a 20 ml syringe and an assortment of needles of varying sizes and gauges from 23 to 26. Palpable lesions that are aspirated most commonly are those in the breast, thyroid, prostate, salivary glands and lymph nodes. The most common non-palpable lesions are usually found in the liver, pancreas and soft tissues. Fine needle aspiration of the breast is easy and highly accurate, diagnosing benign and malignant lesions. Oestrogen and progesterone assays can be performed on specimens obtained by this procedure. Needle aspirations of the thyroid have reduced surgical procedure by about 40 percent. They serve to identify cold nodules with no nucleotide uptake. Moreover 30 percent of cold nodules are cysts, and aspiration therefore provide immediate cures in these cases. Prostatic aspirates are easily performed on male patients if a prostatic nodule is palpable and/or if there is an elevated prostate specific antigen level. The overall accuracy of these aspirates is 97 percent and compares well with tissue core biopsies. Lymph node aspirations are indicated for persistent enlargement and are used primarily to rule out primary or metastatic malignancies. In the latter case they provide the best, least traumatic and quickest way to diagnose inoperable malignancies, and they are also useful for detecting tumour recurrences and, therefore for assessing the effects of adjuvant therapy. Aspiration requiring imaging assistance is usually for deep seated lesions that are not palpable. It is especially useful in diagnosing small (oat) cell carcinoma of the lung, that is not treated surgically. Liver cancers can be most easily assessed by this procedure and the distinction between carcinoma and endocrine tumours of the pancreas is readily made. It is evident that aspiration biopsy is a method of diagnosis with potentially significant benefits. In competent hands, it is safe and reliable.(AU)

Inspiratory valve malfunction in a circle system: pitfalls in capnography

Capnography is a useful technique in monitoring the integrity of anaesthetic equipment such as the malfunctioning of unidirectional valves in circle system. However, the lack of a precise mechanism in existing capnographs to identify the start of inspiration and the beginning of expiration in the capnograms, makes the analysis of the carbon dioxide waveforms during inspiration difficult and thus results in inaccurate assessement of rebreathing. We report a case where, during the malfunction of the inspiratory unidirectional valve in the circle system, the capnograph failed to detect the presence of substantial rebreathing. Critical analysis of the capnogram recorded during the malfunction revealed that there was substantial rebreathing which was underestimated by the capnograph as it reports only the lowest CO2 concentration rebreathed during inspiration in such abnormal situations.(AU)

Abscess - to incise or aspirate? - abstract

A randomized prospective study of 82 patients attending the Paediatric Emergency Department with soft tissue abscesses was undertaken to compare the efficacy of aspiration versus incision and drainage as the method of treatment. Forty patients belonged to the aspiration group and 42 to the incision and drainage as the method of treatment. Forty patients belonged to the aspiration group and 42 to the incision and drainage group. The groups were comparable for age distribution, size and location of abscess and usage of antibiotics. Three complications were noted resulting in minor morbidity but no major complications were encountered. In comparable groups of patients, aspiration alone achieved resolution of the abscess with no significant risks or complications. We conclude that aspiration is an adequate method of treating soft tissue abscesses (AU)