Sir Charles Ballance: pioneer British neurological surgeon.

Sir Charles A. Ballance (1856-1936) began his medical career at St. Thomas's Hospital the University College, London, England, in 1875, receiving honors in every subject and a gold medal in surgery.

Reconciling in vitro and in vivo measurements of aerosol delivery from a metered-dose inhaler during mechanical ventilation and defining efficiency-enhancing factors.

We attempted to resolve the discrepancies in reported data on aerosol deposition from a chlorofluorocarbon (CFC)-propelled metered-dose inhaler (MDI) during mechanical ventilation, obtained by in vivo and in vitro methodologies. Albuterol delivery to the lower respiratory tract was decreased in a humidified versus a dry circuit (16.2 versus 30.

Does resistive loading decrease diaphragmatic contractility before task failure?

While sustaining a load that leads to task failure, it is unclear whether diaphragmatic fatigue develops progressively or occurs only at task failure. We hypothesized that incremental loading produces a progressive decrease in diaphragmatic contractility ever before task failure. Ten subjects generated 60% of maximal transdiaphragmatic pressure (Pdimax) for 2 min, 4 min, and until task failure.

Effect of hyperoxic hypercapnia on variational activity of breathing.

Dysrhythmias of breathing occur in several clinical disorders, but their mechanistic basis is obscure. To understand their pathophysiology, factors responsible for the variability of breathing need to be defined. We studied the effect of hyperoxic hypercapnia (CO2) on the variational activity of breathing in 14 volunteers before and after delivering CO2 nonobstrusively via a plastic hood.

Heparin-induced thrombocytopenia with thrombosis: incidence, analysis of risk factors, and clinical outcomes in 108 consecutive patients treated at a single institution.

Heparin-induced thrombocytopenia with thrombosis (HITT) can lead to serious morbidity and may be potentially fatal. We reviewed our experience with this entity over a 4-year period, to determine the following: 1) incidence and type of thrombosis in patients with heparin-induced thrombocytopenia (HIT), 2) clinical consequences of thrombosis, i.e.

Value of leads V7-V9 in diagnosing posterior wall acute myocardial infarction and other causes of tall R waves in V1-V2.

Left posterolateral chest leads (V7, V8, V9) helped distinguish the multiple causes of tall R waves in V1 and/or V2, diagnosed true posterior myocardial infarction when standard leads did not, and identified the presence or absence of posterior injury in patients with inferior infarction.

Effect of elastic loading on variational activity of breathing.

To examine the effect of elastic loading on variational activity of breathing, we studied 11 healthy subjects breathing at rest and with inspiratory elastic loads of 9 and 18 cm H2O/L, applied randomly for 1 h each. Compared with rest, a load of 18 cm H2O/L decreased gross variability, quantitated as standard deviation, of tidal volume (VT) and expiratory time (TE) (p < 0.01 in both instances) but increased that of inspiratory time (TI) (p < 0.

Relationship between transdiaphragmatic and mouth twitch pressures at functional residual capacity.

The clinical application of transdiaphragmatic twitch pressure (Pdi,tw) response to phrenic nerve stimulation has been hindered by the requirement for placement of oesophageal and gastric balloons. Investigators have reported that mouth twitch pressure (Pmo,tw) estimates Pdi,tw accurately at lung volumes above and below functional residual capacity (FRC). However, it is not known whether Pmo,tw estimates Pdi,tw accurately when stimulation is performed at FRC during relaxed conditions.