FACTORS INFLUENCING THE ARTERIAL OXYGEN TENSION DURING ANAESTHESIA WITH ARTIFICIAL VENTILATION

Factors influencing oxygenation of the arterial blood were studiedin 26 patients, during routine anaesthesia with artificial ventilation.The mean minute volume was 10 1./min and the arterial Pco₂ 27mm Hg. The mean oxygen consumption was 215 ml/min (STPD) andthe physiological deadspace 36 per cent of tidal volume (noallowance being made for the volume of the air passages bypassedby the endotracheal tube). At high levels of inspired oxygenconcentration, the mean alveolar-arterial Po₂ gradient was 145mm Hg, corresponding to a calculated shunt of 11 per cent. Atan alveolar Po₂, of 155 mm Hg the gradient was 52 mm Hg, correspondingto a calculated venous admixture of 9 per cent. There was noprogressive increase in venous admixture during anaesthesiain patients under the age of 43 but most of the older patientsshowed falls and their mean change was significant. Attemptswere made to reduce the venous admixture by hyperinflation ofthe lungs. This was successful in some patients, when a pressureof 40 cm H₂O was maintained for 40 seconds. Lower pressures,and the use of a sustained expiratory pressure of 5 cm H₂O werenot effective. Indices of disordered respiratory function foundin this study were not significantly different from those ina comparable study of anaesthetized patients breathing spontaneously. Present addresses: ^* Department of Anaesthesia, University ofLeeds, 24 Hyde Terrace, Leeds, 2. Present addresses: Veterans Administration Hospital, Salt LakeCity, Utah, U.S.A. Present addresses: University of Natal, Durban, South Africa.     

Schwefelkohlenstoff-Einwirkungen auf die rhino-otologischen Funktionen der BeschÄftigten in der Kunstfaser-Industrie

Zusammenfassung Im Rahmen von Reihenuntersuchungen verschiedener Altersgruppen CS₂-Exponierter in der Kunstfaser-Industrie werden unter Berücksichtigung dort herrschender LautstÄrken die rhino-otologischen Funktionen untersucht. Bei den Exponierten zeigten sich vermehrt trockene NasenschleimhÄute sowie ein olfaktorisches Funktionsdefizit. Bei den otologischen Funktionen fanden sich Reduzierung der Tonschwellen in den hohen Frequenzen, überwiegen des calorisch bedingten Nystagmus bei der Warmspülung und vermehrte pathologische Nystagmusformen. Die Vestibularisbefunde gehen anderen klinischen Erscheinungen voraus und sind als Frühsymptom einer Intoxikation zu werten. Die Vestibularisprüfung wird in den FÄllen empfohlen, wo die Anwendung des EEG auf Schwierigkeiten stö\t. Die Auswirkungen im Bereich der Cochlea führen weder durch CS₂ allein noch in Kombination mit den in der Kunstfaser-Industrie herrschenden LautstÄrken zu einer EinschrÄnkung der akustischen Information.

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CS₂-effects upon olfactory and auditory functions of employees in the synthetic-fiber industry

Summary Examinations of nasal and auditory functions were performed on a number of different age groups of people exposed to CS₂ in the synthetic-fiber industry. In people thus exposed, dry nasal mucous membranes as well as a deficit in olfactory functioning was evident. The auditory examinations showed a reduction of thresholds in the high frequences, a predominance of calorically caused nystagmus, and an increase in pathological forms of nystagmus.The vestibular symptoms precede other clinical evidence and are to be regarded as early symptoms of an intoxication. These vestibular examinations are recommended in all cases where it is difficult to use the EEG. It seems that neither exposure to CS₂ alone nor such exposure in combination with the prevailing noise levels in the synthetic-fiber industry led to a reduction of the acoustic information in the cochlea.

     

Sequence Diversity in tRNA Gene Locus A-L among Iranian Isolates of Entamoeba dispar

Background

A number of methods for detecting diversity in Entamoeba have been described over the years. In the present study the genetic polymorphism of noncoding locus A-L was analyzed using PCR and sequencing in order to clarify the genotypic differences among E. dispar isolates.

Methods

A total of 28 E. dispar from patients with gastrointestinal symptoms were determined and the genomic DNA was extracted directly from stool. For genotype analysis; Locus A-L was amplified by PCR and PCR products were sequenced. The sequences obtained were edited manually and aligned using Gene Runner software.

Results

With sequencing of PCR products a reliable genetic diversity in size, number and position of the repeat units were observed among the Iranian E. dispar isolates in locus A-L gene. Sequences showed variation in length from 448bp to 507bp and seven distinct types were identified.

Conclusion

The genetic diversity of loci like A-L shows them to be suitable for epidemiological studies such as the characterization of the routes of transmission of these parasites in Iran.     

An unusual right popliteal vein aneurysm in an adult cadaver: A case report

The incidence of venous aneurysm is less than arterial aneurysms. Most are incidental findings with no major clinical significance. However, popliteal vein aneurysms (PVA) may be potentially life threatening, as they can be a source of pulmonary embolism and potentially even death. We report a case of right PVA in a 67-year-old male cadaver. Information from this case study may contribute to an improved understanding of these phenomena, including early detection of these or similar thromboembolic events.     

Decal bone matrix as a local antibiotic delivery vehicle in a MRSA-infected bone model: An experimental study

Background:

Polymethyl methacrylate (PMMA) antibiotic beads though have proved their utility as a local antibiotic delivery system, however, there are limitations. Decalcified bone matrix (DBM) as a vehicle of antibiotics can serve the purpose, provided a minimum inhibitory concentration is sustained. Healing of the defect and avoiding the second surgery is another advantage. We studied the DBM as the delivery vehicle for vancomycin in controlling the methicillin-resistant Staphylococcus aureus (MRSA) osteomyelitis as well as healing of the cavity simultaneously in an experimental study.

Materials and Methods:

An in vitro study was conducted to optimize vancomycin impregnation in the DBM. For the in vivo study, a unicortical defect was created in the metaphysis of the distal femur in 18 rabbits. After contaminating the defect with MRSA, rabbits were divided into three groups. Group I (eight limbs) received no graft. Defects in group II (11 limbs) were filled with plain DBM chips and in group III (14 limbs), cavities were implanted with vancomycin-impregnated decal bone chips. Rabbits were assessed by clinical, radiological, histological, gross examination and bacterial load assay. High Performance Liquid Chromatography HPLC analysis of vancomycin in group III was done to assess the concentration in DBM chips.

Results:

In group I, the infection persisted throughout the period of the study. Group II showed the fulminated infection at the grafted site with DBM chips sequestrating out. Vancomycin-impregnated decal chips in group III did not show any sign of infection and eventually incorporated. The bacterial load study showed a progressive load change and HPLC revealed an effective antibiotic concentration up to 3 weeks in both in vitro and in vivo.

Conclusion:

Decal bone chips were effective as the local antibiotic delivery vehicle in preventing the MRSA osteomyelitis model. It eluted vancomycin significantly and the graft uptake was also excellent. Allogeneic decal grafts eliminated the need for second surgery and acted as an excellent delivery vehicle for antibiotics.     

Intertrochanteric fractures in elderly high risk patients treated with Ender nails and compression screw

Background:

Ender and Simon Weidner popularized the concept of closed condylocephlic nailing for intertrochanteric fractures in 1970. The clinical experience of authors revealed that Ender nailing alone cannot provide secure fixation in elderly patients with osteoporosis. Hence we conducted a study to evaluate the efficacy of a combined fixation procedure using Ender nails and a cannulated compression screw for intertrochanteric fractures.

Materials and Methods:

76 patients with intertrochanteric fractures were treated using intramedullary Ender nails and cannulated compression screw from January 2004 to December 2007. The mean age of the patients was 80 years (range 70-105 years).Using the Evan’s system of classification 49 were stable and 27 unstable fractures. Inclusion criteria was high risk elderly patients (age > 70 years) with intertrochanteric fracture. The exclusion criteria included patients with pressure sores over the trochanteric region. Many patients had pre-existing co-morbidities like diabetes mellitus, hypertension, COPD, ischemic heart disease, CVA and coronary artery bypass surgery. The two Ender nails of 4.5mm each were passed across the fracture site into the proximal neck. This was reinforced with a 6.5 mm cannulated compression screw passed from the sub trochanteric region, across the fracture into the head.

Results:

The mean follow-up was 14 months (range 9-19 months) Average time to fracture union was 10 weeks (range 6-16 weeks). The mean knee ROM was 130° (± 5°). There was no case of nail penetration into hip joint. In five cases with advanced osteoporosis there was minimal migration of Ender nails distally.

Conclusions:

The Ender nailing combined with compression screw fixation in cases of intertrochanteric fractures in high risk elderly patients could achieve reliable fracture stability with minimal complications.     

Haemolymph Components of Infected & None Infected Lymnaea snails with Xiphidiocercariae

Background

In this study the haemolymph components of infected and none infected Lymnaea gedrosiana with xiphidiocercaria larvae was compared.

Methods

Five hundred Fifty Lymnaea snails were collected from Ilam and Mazandaran provinces, Iran, during 2008–2009. The snails were transported to the lab at Tehran University of Medical Sciences and their cercarial sheddings were studied. Haemolmyphs of snails were extracted and cells were counted using haemocytometer and cell-surface carbohydrate were recognized by conjugated lectin (Lentil). Haemolymph protein concentrations were measured by Bradford protein assay method and soluble protein compositions were determined on sodium dodecyl sulphate polyacrilamide gel electrophoresis (SDS-PAGE).

Results

From the 550 examined Lymnaea snails for cercariae, 27 snails were infected with xiphidiocercariae. Mean of haemolymph cells (haemocyte) number were obtained 93480±2.43 (cells/ml) for none infected snails (25 snail) and 124560±2800 (cells/ml) for infected snails (25 snail). Mannose carbohydrate was recognized on haemocyte of none infected and infected snails. Mean of protein concentration of haemolymph plasma was obtained as 1354±160 µg/ml (1.4 mg/ml) for none infected snails (25 snails) and 1802±138 µg/ml (1.8 mg/ml) for infected snail (25 snails). Comparing to none infected snails, the SDS-PAGE results of haemolymph plasma of infected snails, showed an extra protein band (70 kDa). The results showed a significant difference between the amounts and the kinds of proteins in haemolymph of infected and none infected snails.

Conclusion

This information might be useful to understand of parasite detection, adhesion, engulfment and antigen agglutination by snail.