The delivery of oxygen by arterial blood to the tissues of the body has a number of critical determinants including blood oxygen concentration (content), saturation (S O2 ) and partial pressure, haemoglobin concentration and cardiac output, including its distribution. The haemoglobin-oxygen dissociation curve, a graphical representation of the relationship between oxygen satur-ation and oxygen partial pressure helps us to understand some of the principles underpinning this process. Historically this curve was derived from very limited data based on blood samples from small numbers of healthy subjects which were manipulated in vitro and ultimately determined by equations such as those described by Severinghaus in 1979. In a study of 3524 clinical specimens, we found that this equation estimated the S O2 in blood from patients with normal pH and S O2 >70% with remarkable accuracy and, to our knowledge, this is the first large-scale validation of this equation using clinical samples. Oxygen saturation by pulse oximetry (S pO2 ) is nowadays the standard clinical method for assessing arterial oxygen saturation, providing a convenient, pain-free means of continuously assessing oxygenation, provided the interpreting clinician is aware of important limitations. The use of pulse oximetry reduces the need for arterial blood gas analysis (S aO2 ) as many patients who are not at risk of hypercapnic respiratory failure or metabolic acidosis and have acceptable S pO2 do not necessarily require blood gas analysis. While arterial sampling remains the gold-standard method of assessing ventilation and oxygenation, in those patients in whom blood gas analysis is indicated, arterialised capillary samples also have a valuable role in patient care. The clinical role of venous blood gases however remains less well defined.

https://breathe.ersjournals.com/content/breathe/11/3/194.full.pdf

Relating oxygen partial pressure, saturation and content: the haemoglobin–oxygen dissociation curve

Talaromyces (Penicillium) marneffei is an important pathogenic thermally dimorphic fungus causing systemic mycosis in Southeast Asia. The clinical significance of T. marneffei became evident when the human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome epidemic arrived in Southeast Asia in 1988. Subsequently, a decline in the incidence of T. marneffei infection among HIV-infected patients was seen in regions with access to highly active antiretroviral therapy and other control measures for HIV. Since the 1990s, an increasing number of T. marneffei infections have been reported among non-HIV-infected patients with impaired cell-mediated immunity. Their comorbidities included primary adult-onset immunodeficiency due to anti-interferon-gamma autoantibodies and secondary immunosuppressive conditions including other autoimmune diseases, solid organ and hematopoietic stem cell transplantations, T-lymphocyte-depleting immunsuppressive drugs and novel anti-cancer targeted therapies such as anti-CD20 monoclonal antibodies and kinase inhibitors. Moreover, improved immunological diagnostics identified more primary immunodeficiency syndromes associated with T. marneffei infection in children. The higher case-fatality rate of T. marneffei infection in non-HIV-infected than HIV-infected patients might be related to delayed diagnosis due to the lack of clinical suspicion. Correction of the underlying immune defects and early use of antifungals are important treatment strategies. Clinicians should be familiar with the changing epidemiology and clinical management of T. marneffei infection among non-HIV-infected patients.

Talaromyces (Penicillium) marneffei infection in non-HIV-infected patients.

The frequency of complications following radial artery cannulation for monitoring purposes was determined in 1,699 cardiovascular surgical patients and in 83 patients in whom cannulation was performed in another artery after failure at the radial site. Patients were examined and radial artery flow d

On the safety of radial artery cannulation

Traditional conscious sedation for endobronchial ultrasound procedures places patients at risk of desaturation, and high-flow nasal oxygen may reduce the risk. We designed a parallel-group randomised controlled trial of high-flow nasal oxygen at a flow rate of 30-70 l.min-1 via nasal cannulae, compared with standard oxygen therapy at 10 l.min-1 via a bite block in adults planned for conscious sedation for endobronchial ultrasound. The primary outcome was the proportion of patients experiencing desaturation (defined as SpO2 < 90%). Secondary outcomes included oxygen saturation after pre-oxygenation, lowest oxygen saturation during procedure, number of hypoxic episodes, duration of hypoxia, end-procedure end-tidal CO2 , satisfaction scores and complications. Thirty participants were allocated to each group. Baseline patient characteristics, procedure time and anaesthetic agents used were similar between the groups. Desaturation occurred in 4 out of 30 patients allocated to the high-flow nasal oxygen group, compared with 10 out of 30 allocated to the standard oxygenation group, a non-significant difference (p = 0.07) with intention to treat analysis. The difference was significant (p = 0.047) when using a per-protocol analysis. Oxygen saturation after pre-oxygenation and the lowest oxygen saturation during procedure were significantly higher in the high-flow nasal oxygen group compared with the standard oxygenation group; median (IQR [range] 100 (99-100 [93-100]) vs. 98 (97-99 [94-100]), p = 0.0001 and 97.5 (94-99 [77-100]) vs. 92 (88-95 [79-98]), p < 0.001, respectively. There were no differences in other secondary outcomes. Although high-flow nasal oxygen may prevent desaturation due to some causes, it does not protect against hypoxaemia in all circumstances.

https://associationofanaesthetists-publications.onlinelibrary.wiley.com/doi/pdf/10.1111/anae.14156

A randomised controlled trial comparing high-flow nasal oxygen with standard management for conscious sedation during bronchoscopy

Background: The number of patients with invasive home mechanical ventilation (HMV) following unsuccessful weaning is steadily increasing, but little is known about the living conditions and health-related quality of life (HRQL) in these patients. Objectives: To establish detailed information on living conditions and HRQL in patients with invasive HMV. Methods: The Severe Respiratory Insufficiency Questionnaire (SRI) was used to measure specific HRQL aspects in addition to patient interviews on individual living conditions during home visits. Results: Thirty-two patients with lung disease, most prominently COPD (n = 18), and neuromuscular disorders (n = 14) were included. The overall mean SRI summary scale score (range 0-100) was 53 ± 16, with a broad range amongst individuals (23-86). Neuromuscular patients were younger than those with lung diseases (49 ± 18 vs. 67 ± 11 years; p Conclusions: Patients undergoing invasive HMV primarily following unsuccessful weaning reported an individual HRQL which, when taken together, was highly heterogeneous and ranged from very good to extremely bad. Older patients with COPD and more comorbidities are likely to have a worse HRQL than neuromuscular patients, while the living situation does not influence the HRQL.

/pdf/invasive-home-mechanical-ventilation-living-conditions-and-1llvq6chaz.pdf

Invasive home mechanical ventilation: living conditions and health-related quality of life.

Low utilisation of diagnostic microbiology for community acquired pneumonia in regional Victoria

Purpose
To explore the influence of descriptive differences in items evaluating mobility on index scores generated from two generic preference-based health-related quality of life (HRQoL) instruments.

Framing of mobility items: a source of poor agreement between preference-based health-related quality of life instruments in a population of individuals receiving assisted ventilation.

acute promyelocytic leukemia (APL): II. Clinical efficacy and pharmacokinetics in relapsed patients. Blood 1997; 89: 3354–60. 7 Fujisawa S, Ohno R, Shigeno K, Sahara N, Nakamura S, Naito K et al. Pharmacokinetics of arsenic species in Japanese patients with relapsed or refractory acute promyelocytic leukemia treated with arsenic trioxide. Cancer Chemother Pharmacol 2007; 59: 485–93. 8 Kumana CR, Au WY, Lee NSL, Kou M, Mak RWM, Lam CW et al. Systemic availability of arsenic from oral arsenic trioxide used to treat patients with hematological malignancies. Eur J Clin Pharmacol 2002; 58: 521–6. 9 Buxton ILO. Pharmacokinetics and pharmacodynamics. In: Brunton LL, Lazo JF, Parker KL, eds. Goodman and Gilman’s Pharmacological Basis of Therapeutics, 11th edn. New York: McGraw Hill; 2005; 1–39. 10 Miller WH, Levine K, DeBlasio A, Frankel A, Dimitrovsky E, Warrell RP. Detection of minimal residual disease in acute promyelocytic leukemia by a reverse transcription polymerase chain reaction assay for the PML/RAR-a fusion mRNA. Blood 1993; 82: 1689–94. 11 Au WY, Kumana CR, Kou M, Mak R, Chan GCF, Lam CW et al. Oral arsenic trioxide in the treatment of relapsed acute promyelocytic leukemia. Blood 2003; 102: 407–8.

Late presentation of familial Mediterranean fever associated with P369S/R408Q variant in the MEFV gene.

Background. Oxaliplatin in combination with 5-fluorouracil (5-FU) and leucovorin (FOLFOX) is a common chemotherapeutic regimen for advanced colorectal cancer. Here, we present a case of interstitial lung disease associated with FOLFOX therapy. Case report. A 74-year-old man with a history of metastatic colorectal cancer was admitted with a four week history of progressive dyspnoea and evidence of severe respiratory failure. He had recently completed six cycles of FOLFOX chemotherapy in the months prior to presentation. Investigations did not reveal convincing evidence of infection or pulmonary embolism. CT chest demonstrated widespread pulmonary infiltrates and interlobular septal thickening. The patient was commenced on both broad spectrum antibiotic therapy and high dose corticosteroid treatment however his respiratory failure continued to progress. The patient died four days after admission due to progressive respiratory failure. Subsequent post-mortem examination demonstrated evidence of diffuse alveolar damage without evidence of tumour infiltration, infection or pulmonary embolism. Conclusions. Although infrequent, pulmonary toxicity can occur in association with FOLFOX therapy. Cessation of therapy and prompt initiation of corticosteroids may improve outcomes.

/pdf/interstitial-lung-disease-in-a-patient-treated-with-4yp3iobeeg.pdf

Interstitial lung disease in a patient treated with oxaliplatin, 5-fluorouracil and leucovorin (FOLFOX) for metastatic colorectal cancer

Autocycling is a form of patient-ventilator asynchrony that can occur during mechanical ventilation. In the case described, autocycling during noninvasive ventilation led to severe hyperventilation...

Liam M. Hannan

Papers

Low utilisation of diagnostic microbiology for community acquired pneumonia in regional Victoria

Framing of mobility items: a source of poor agreement between preference-based health-related quality of life instruments in a population of individuals receiving assisted ventilation.

Late presentation of familial Mediterranean fever associated with P369S/R408Q variant in the MEFV gene.

Interstitial lung disease in a patient treated with oxaliplatin, 5-fluorouracil and leucovorin (FOLFOX) for metastatic colorectal cancer

Autocycling During Noninvasive Positive Pressure Ventilation Producing a Prolonged Severe Apnea and Syncope.