Changes in transcutaneous oxygen partial pressure as an index of response to inhaled methacholine in asthmatic patients.

Bronchoconstriction and hypoxemia have been reported to occur during airway challenges, but the correlation between changes in forced expiratory volume in 1 s (FEV1) and transcutaneous oxygen partial pressure (tcPO2) during methacholine provocation tests has not yet been established (to our knowledge). In 15 symptom-free atopic asthmatic patients and 5 normal subjects, variations in tcPO2 and FEV1 were simultaneously measured during inhalation of doubling methacholine concentrations; the drug concentrations causing a 20 percent decrease in control FEV1 and tcPO2 (PC20FEV1 and PC20tcPO2, respectively) were subsequently calculated. In patients, geometric mean PC20FEV1 and PC20TcPO2 were 1.31 (range, 0.16 to 5.19) and 1.26 (range, 0.29 to 5.82) mg/ml, respectively. In addition, in six patients, methacholine-induced fall in tcPO2 was accompanied by similar changes in arterial PO2. Methacholine inhalation caused no change in tcPO2 or FEV1 in normal subjects. The independent effects of deep breath tests and bronchoconstriction on PC20tcPO2 were studied in five patients challenged on two separate occasions, with and without FEV1 assessment; in these patients, PC20tcPO2 were similar on both the study days. The results indicate that, in asthmatic patients, methacholine-induced bronchoconstriction causes parallel decreases in FEV1 and tcPO2. The tcPO2 monitoring may serve as a tool in the assessment of airway hyperreactivity when active patient's cooperation is scarce.

[Progressive pneumoperitoneum in the preparation for surgical intervention for voluminous ventral hernias]. / Il pneumoperitoneo progressivo nella preparazione all'intervento chirurgico per voluminose ernie ventrali.

The paper report three patients suffering from voluminous ventral hernias who were treated using progressive pneumoperitoneum as a preparative method prior to reparative surgery. On the basis of the results obtained, the authors sustain the rationality, safety and efficacy of the procedure, in particular given its ability to reestablish good respiratory and circulatory function in those cases where the latter were severely affected by hernia. Since this method needs a longer application time and therefore involves a greater economic burden, pneumoperitoneum should probably be reserved for selected cases, and alternative techniques should be used in patients where hernia is more easily resolved.

[Pneumoperitoneum in preparation for surgery of large ventral hernia]. / Il pneumo-peritoneo nella preparazione agli interventi dei grandi laparoceli.

Reparative surgery of ventral hernia may be relatively simple or, on the other hand, the surgeon may be confronted with a number of tactical and technical problems. Many of these are caused by the "loss of the right of domicile". In order to avoid this particular condition it is useful to resort to preoperative pneumoperitoneum. This method entails the gradual and progressive introduction of air into the peritoneal cavity. In this way abdominal capacity is increased and it is therefore possible to re-insert all the viscera into their natural cavities avoiding all the harmful consequences for respiratory and cardio-circulatory organs following forced replacement. Preoperative pneumo-peritoneum is a relatively well consolidated surgical technique in large scale eventration. The methods is simple to perform and has a low incidence of complications.

Effect of aminophylline aerosol on the bronchial response to ultrasonic mist of distilled water in asthmatic patients.

To ascertain whether inhaled aminophylline was effective in preventing the bronchial response induced by inhalating of an ultrasonic mist of distilled water (UMDW), we examined 8 asthmatic patients who had previously been shown to be reactive to this agent. Patients were given either 30 mg aminophylline or saline placebo aerosols followed by inhalation of 60 liters of UMDW; measurements of specific airway conductance (sGaw) were made before and after aminophylline or saline administration and after UMDW challenge. UMDW consistently induced a significant decrease in sGaw in all patients; however, in our subjects as a group, the degree of UMDW-induced bronchoconstriction was significantly less after premedication with aminophylline aerosol than after saline (p less than 0.01). Our results suggest that aminophylline is effective in preventing UMDW-induced bronchoconstriction; the possible relationships between bronchial response to UMDW and its modulation by inhaled aminophylline are discussed.

Influence of inspiratory flow rate on the bronchial response to ultrasonic mist of distilled water in asthmatic patients.

In an attempt to evaluate the influence of inspiratory flow rate on the sensitivity of the bronchial challenge with ultrasonic mist of distilled water (UMDW), we studied 8 symptom-free asthmatic patients who inhaled 60 liters of UMDW at a flow rate of either 0.35 or 1.2 1/s on two separate occasions. Tidal volume and the total duration of the respiratory cycle were kept constant during all inhalation tests. The bronchial response was assessed in terms of percent changes of baseline airway conductance. The results demonstrate that the mean bronchial response after 0.35 1/s UMDW inhalation was significantly greater than after 1.2 1/s inhalation of comparable doses of UMDW. Furthermore, 3 patients who developed a significant bronchoconstriction after 0.35 1/s UMDW inhalation showed only a mild, not significant bronchial response when the mist was inhaled at 1.2 1/s. We conclude that the sensitivity of the UMDW challenge is increased if the agent is inhaled during slow, tidal breathing.