In dairy goats, the kid rearing system can have critical importance in financial returns. Commonly used criteria for the choice of rearing system are not always clear due to the high number of factors involved. The aim of this study was to quantify all those factors to facilitate decision making. So, the effect of two different kid rearing systems, mixed rearing system (MRS) and artificial rearing system (ARS), on milk yield, milk composition and somatic cell count (SCC), milk yield loss at weaning for MRS, kid growth and costs of the different traits on the financial returns in Murciano-Granadina breed goats was studied. Twenty-four goats per group were used. In the MRS, goats reared only one kid, which had free access to goat milk 24 h a day and were weaned at week 6 of lactation, whereas kids in the ARS were separated from their mothers at kidding, colostrum and artificially reared. In both systems, dams were machine-milked once a day throughout lactation and the records took place weekly. Potential milk yield was estimated according to the oxytocin method up to week 12 of lactation, and was similar for both rearing systems, although a 12.3% drop in potential milk yield at weaning was observed for MRS. During the first 6 weeks of lactation, marketable milk was lower for dams in MRS compared to those in ARS (72.1 v. 113.0 l), but similar for the rest of the experiment (101.5 v. 99.4 l, respectively). Marketable milk composition and SCC throughout the 12 weeks of lactation were unaffected by the rearing system. Artificial rearing system entailed an increment in production cost of 22.2€ per kid compared to the rearing by MRS. A similar economic return per goat and kid was obtained from ARS and MRS in this experiment, although, due to one herd’s prolificacy of 1.8, the actual results would be 16.2€ per goat in favour of MRS. The real interest of this experiment may be the possibility of extrapolation to different flocks with diverse levels of milk production, prolificacy and prices and costs for incomes and outputs, to estimate the production system that increases returns. In conclusion, the results showed an increase in the cost of €22.2 per kid bred in the ARS, compared to the MRS, and a final return of 16.2€ per goat in favour of the mixed system.

John Searle's attack on various interpretations of Artificial Intelligence has been the most thorough challenge to the philosophical foundations of Artificial Intelligence. In this paper we attempt to contribute to a growing body of argument as to why Searle is mistaken in his attack. We propose an analogy between intelligent objects and flying objects, leading to a definition of Artificial Intelligence similar to that of aerodynamics, but one which attempts to present general laws of intelligence in man and machines alike.

Rehabilitation of voice and speech after total laryngectomy has become established practice in recent years. A voice prosthesis is placed within a surgically produced fistula between the trachea and upper oesophagus and acts as a one way valve, allowing passage of pulmonary air from the trachea into the oesophagus and preventing aspiration of food and fluid from the oesophagus into the trachea. Persistent leakage through or around these prostheses is a recognized complication, the aetiology of which can vary widely, from mechanical issues with the prostheses themselves to anatomical and physiological issues associated with the reconstructed pharynx.

We report a new technique of using Dysport® in the management of intractable central leakage due to premature and forceful closure of the upper oesophageal sphincter during swallowing. This resulted in the pooling of fluids around the posterior flange of the prosthesis. This, along with the increased pressure from the muscle contraction, led to central leakage, as identified on videofluoroscopy. An injection of Dysport paralysed the upper oesophageal sphincter, preventing pooling of fluids around the prosthesis and the forcing open of the valve. The effect was to eliminate the leakage, and the patient did not require further injections over the following 22 months.

Several problems have been observed when performing the classic endoscopic technique for voice restoration following laryngectomy. An easy and safe method is described for the insertion of a Provox® voice prosthesis using a Yankauer tonsil suction tube and an antrum trocar with an irrigation cannula.

The development of hypertrophic mucosa and granulation tissue around a tracheo-oesophageal fistula voice prosthesis is a commonly encountered problem occurring in 15–20 per cent of patients. Upsizing of the voice prosthesis as well as cautery (silver nitrate and electocautery) are used to counteract this problem to a varying degree of success. The use of the CO2 laser has been mentioned by some authors but details of the method and results have not been published. We report the successful use of the KTP laser for removing such granulations whilst retaining the valve and discuss the reasons why this method should be considered.

Cardiac arrest is a dramatic condition leading to sudden death if someone cannot perform two interventions, basic life support and early defibrillation, that have been proved to improve long-term survival. The modern era of cardiopulmonary resuscitation began with a description of closed chest cardiac massage by Kouwenhoven in 1960. Research to make advances in cardiac arrest is a very difficult task. Experts set up a series of guidelines that represent a keystone for educational needs and evolving technology. There is a consensus that the highest potential survival rate from cardiac arrest can only be achieved when the following sequence of events occurs as rapidly as possible: (1) recognition of early warning signs, (2) activation of the emergency medical services, (3) basic cardiopulmonary resuscitation, (4) cardiac defibrillation, (5) management of the airway and ventilation of the lungs, and (6) intravenous (i.v.) administration of medications. These events are necessary for any success of emergency cardiovascular care. They are linked in a chain of survival. The links in the adult chain of survival are: early access; early CPR; early defibrillation; and early acute cardiac life support. The 'Utstein style', recently introduced, represents a standard of practice both inside and outside hospital with recommended guidelines for the uniform reporting of clinical data from the patient suffering cardiac arrest. According to the concept of the chain of survival, the Utstein style delineates time and establishes a set of core and supplemental times to be recorded that provide important characteristics of the response of victims of cardiac arrest.

Background and objective Pressure-controlled inverse ratio ventilation was compared with controlled mechanical ventilation in patients after cardiac surgery.

Methods Ten patients were ventilated after sternal closure using a Siemens Servo 900C ventilator to a target end–tidal PCO2 of 4.0 kPa. They were randomized to receive controlled mechanical ventilation or pressure–controlled inverse ratio ventilation. CO2-based data were recorded on a laptop personal computer, which together with arterial PCO2 permitted measurement of the respiratory dead space. Once measurements were complete the ventilator was switched to the other mode and new measurements taken. Results PaCO2 and VCO2 were virtually the same in both modes. Peak airway pressure (17.2±2.7 vs. 20.8±2.5 cmH2O, P < 0.01) and minute ventilation (4.9±1.1 vs. 5.3±1.1 cmH2O, P < 0.01) were less during pressure–controlled inverse ratio ventilation. Physiological dead space fraction (0.39±0.06 vs. 0.51±0.05, P <0.001), airway dead space (56±15 vs. 81±15 mL, P <0.001) and alveolar dead space fraction (0.25±0.07 vs. 0.31±0.09, P<0.01) were all less during pressure–controlled inverse ratio ventilation. There were no differences in heart rate or mean arterial pressure.

Conclusions The prolonged inspiratory period and pressure–controlled flowpattern of pressure–controlled inverse ratio ventilation reduce the alveolar and airway dead spaces, and give lower peak airway pressures, compared with conventional ventilation, in cardiac surgical patients.

A 51-year-old man presented with a right upper lobe adenocarcinoma with carinal extension. He underwent a right sleeve pneumonectomy, which involved a carinal resection with anastomosis between the trachea and left main bronchus. This report describes the successful use of jet ventilation, administered via the lumen of the bronchial blocker of a Univent tube. During 15 min of carinal resection, oxygenation of his left lung was maintained with the bronchial blocker bridging the airway discontinuity.

The VersaMed 201 is a lightweight, computer-controlled, electrically driven ventilator, designed for transport, home-ventilation and field use. We have evaluated the device in human beings with healthy and pathological lungs. In the first part of the study, the VersaMed was substituted for a standard operating room ventilator for 15–30 min during elective surgery in 20 subjects. In the second stage of the study, 20 patients with lung pathology who were being ventilated in the critical care department were transferred to the VersaMed for a 30-min period. In all the patients studied, arterial blood gases, haemodynamic parameters and other respiratory variables were maintained at similar values seen with the standard ventilators used. We conclude that the VersaMed 201 is suitable for use in human beings with healthy and pathological lungs as a reliable, portable ventilator.

Arterial carbon dioxide partial pressure measurements using the NBP-75® microstream capnometer were compared with direct PaCO2 values in patients who were (a) not intubated and spontaneously breathing, and (b) patients receiving intermittent positive pressure ventilation of the lungs and endotracheal anaesthesia. Twenty ASA physical status I–III patients, undergoing general anaesthesia for orthopaedic or vascular surgery were included in a prospective crossover study. After a 20-min equilibration period following the induction of general anaesthesia, arterial blood was drawn from an indwelling radial catheter, while the end-tidal carbon dioxide partial pressure was measured at the angle between the tracheal tube and the ventilation circuit using a microstream capnometer (NBP-75®, Nellcor Puritan Bennett, Plesanton, CA, USA) with an aspiration flow rate of 30 mL min−1. Patients were extubated at the end of surgery and transferred to the postanaesthesia care unit, where end-tidal carbon dioxide was sampled through a nasal cannula (Nasal FilterLine, Nellcor, Plesanton, CA, USA) and measured using the same microstream capnometer. In each patient six measurements were performed, three during mechanical ventilation and three during spontaneous breathing. A good correlation between arterial and end-tidal carbon dioxide partial pressure was observed both during mechanical ventilation (r = 0.59; P = 0.0005) and spontaneous breathing (r = 0.41; P = 0.001); while no differences in the arterial to end-tidal carbon dioxide tension difference were observed when patients were intubated and mechanically ventilated (7.3 ± 4 mmHg; CI95: 6.3–8.4) compared to values measured during spontaneous breathing in the postanesthesia care unit, after patients had been awakened and extubated (6.5 ± 4.8 mmHg; CI95: 5.2–7.8) (P = 0.311). The mean difference between the arterial to end-tidal carbon dioxide tension gradient measured in intubated and non-intubated spontaneously breathing patients was 1 ± 6 mmHg (CI95: -11–+13). We conclude that measuring the end-tidal carbon dioxide partial pressure through a nasal cannula using the NBP-75® microstream capnometer provides an estimation of arterial carbon dioxide partial pressure similar to that provided when the same patients are intubated and mechanically ventilated.

We describe a modified technique for the introduction of the Groningen speech valve. This technique can be used in patients in whom the standard technique is either difficult or impossible.

To use end-tidal PCO2 as a non-invasive estimate of arterial PCO2, one adds a nominal value, representing the arterial–end-tidal PCO2 difference. How much does one add? We hypothesized that, halving the ventilator rate and simultaneously doubling tidal volume, the immediate change in end-tidal PCO2 would be proportional to the original arterial-end-tidal PCO2 difference. We ventilated 31 patients at 20 breaths per minute (bpm), sampled arterial blood, and changed the rate to 10 bpm. The change in end-tidal PCO2 was, as hypothesized, positively correlated to the original arterial–end-tidal difference at 20 bpm (r = 0.64). End-tidal PCO2 increased in 23 patients. Thus, in theory, this method could offer some improvement in the estimate of arterial PCO2 from end-tidal. However, because of the considerable spread of values, a separate study is needed for verification

This study was performed to assess the survival times of the Provox™ valve in the Manchester area. Thirty-nine patients from four hospitals, representing 81 valve failures, were studied. The effects of the timing of the tracheo-oesophageal puncture, previous radiotherapy, and the presence and timing of cricopharyngeal myotomy on valve life were analysed. Regression analysis using an extension of the Cox model to allow strata showed that the lifetime of the first valve only is adversely affected by previous radiotherapy. The other covariates do not have a statistically significant effect on valve survival. The median valve survival is 4.5 months, (range one to 12 months). A small percentage of valve users with particularly frequent valve failures may require additional support and prolonged anti-fungal therapy.

The Provox™ voice prosthesis has been used in our department since September 1992 for postlaryngectomy voice rehabilitation. This prosthesis is an indwelling low-resistance tracheoesophageal valve. The cohort consisted of 28 laryngectomees with a mean follow-up time of 352 days. The average valve life before failure was 148 days. Speech intelligibility of 85 per cent was achieved for complete sentences. No major surgical problems were associated with the valve insertion or its use. Replacement of the prosthesis as an outpatient procedure was accomplished without difficulty.

Blom—Singer valve prosthesis is an increasingly popular technique for voice rehabilitation in alaryngeal patients. Although primary voice puncture is being practised, the creation of the tracheo-oesophageal fistula is performed in the majority of patients as a secondary procedure.

We describe a technique of secondary tracheo-oesophageal puncture using the flexible endoscope which can be performed under local anaesthetic and sedation. The technique overcomes the difficulty of passing a rigid oesophagoscope or forceps to the level of the tracheostome in a scarred and irradiated neck. The new technique also obviates the need for general anaesthesia.

We have successfully used the technique in three patients.

Various techniques for performing a secondary tracheo-oesophageal puncture to enable insertion of a speech prosthesis in laryngectomized patients have been described. We describe a modification that allows a safe secondary tracheooesophageal puncture under local anaesthesia using standard equipment available in an ENT department.

Abstract The combination of a narrow oesophageal lumen and a hypertonic pharyngo-oesophageal (P-E) segment following laryngectomy and secondary tracheo-oesophageal puncture (TEP) can cause obstruction of a voice prosthesis and consequently prevent phonation. The ‘Allan Johnson’ modification of the Bivona voice prosthesis incorporates a stainless steel slide and has been successfully used to remedy such a circumstance.

This paper compares the physical parameters of the newer Groningen low resistance and Provox indwelling laryngectomy prostheses with the established and original Groningen device.

In vitro pressure/flow profiles were determined, using specially designed apparatus, in 44 standard Groningen high resistance (GHR), 37 Groningen low resistance (GLR) and 19 Provox tracheo-oesophageal prostheses prior to insertion. GHR valves had significantly higher forward opening pressures than both the newer valves and the GHR was significantly higher than the Provox (p<0.01: Mann-Whitney U-test). The mean forward resistance of GHR was significantly higher than that of both; the Provox valve was significantly lower than that of GLR (p<0.0001: Mann-Whitney U-test). This may be of relevance with respect to patient acceptability, voice quality and effective duration of valve action.