Gastrocnemius recession: A cadaveric study of surgical safety and effectiveness

Background and purpose — Many methods of gastrocnemius lengthening have been described, with different surgical challenges, outcomes, and risks to the sural nerve. Our aims were (1) to locate the gastrocnemius muscular-tendinous junction in relation to the mid-length of the fibula (from here on designated the mid-fibula), (2) to compare the dorsiflexion achieved with dorsal recession or ventral recession, and (3) to determine the risk of injury to the sural nerve during gastrocnemius recession.

Methods — In 10 pairs of fresh-frozen adult cadaveric lower extremities transected above the knee, we measured dorsiflexion, performed dorsal or ventral gastrocnemius recession at the mid-fibula, and then measured the increase in dorsiflexion and fasciotomy gap. We noted the course of the sural nerve and whether the gastrocnemius muscle provided it with enough muscular coverage to protect it during recession.

Results — Dorsal and ventral recession produced statistically (p < 0.05) and clinically significant mean increases in dorsiflexion with extended knee from 12° to 19°, but they were not statistically significantly different from each other in this measure or in fasciotomy gap size. At the mid-fibula, the sural nerve coursed superficially between both heads of the gastrocnemius muscle in 14 of 20 specimens. Sufficient gastrocnemius muscle coverage to protect the sural nerve was provided by the medial head in 18 of 20 specimens and by the lateral head in only 5 of 20 specimens.

Interpretation — A ventral gastrocnemius recession proximal to the mid-fibula level poses less risk to the sural nerve than a recession at the mid-fibula. This procedure provides adequate lengthening (1–3?cm) and increased dorsiflexion (compared with baseline), with less risk to the sural nerve than is incurred with recession at the mid-fibular reference line.     

Predictors for successful PBSC collection on the fourth day of G‐CSF‐induced mobilization in allogeneic stem cell donors

Peripheral blood stem cells (PBSCs) used for allogeneic transplantation are collected by apheresis after pre‐treatment of donors with G‐CSF. Using modern apheresis devices stem cells can be collected more efficiently. It was studied whether collection on the 4th instead of the 5th day after initiation of G‐CSF treatment might be feasible. Stem cell yields that could have been collected on day 4 were calculated in two cohorts treated with 10 µg/kg G‐CSF once daily (n = 106, cohort I) or 5 µg/kg twice daily schedule (n = 85, cohort II). Harvests were predicted using the median collection efficiency (CE) of the apheresis machine and regarded successful when > 5.0 x10⁶ CD34^+/kg recipient body weight. Successful harvests at day 4 could have been obtained in only 22.6% and 41.2% of donors in cohort I and II respectively, while the expected successful collections on day 5 were 55.7% and 76.5%. Individual donor factors that correlated with a successful harvest on day 4 were weight, BMI, age, ratio donor/recipient weight and total G‐CSF dose in cohort I, whereas ratio donor/recipient weight was the only significant predictor in cohort II. Donor weight, BMI and total G‐CSF dose correlated positively with CD34⁺ values in the blood on day 4 in all donors. However, donor characteristics were not able to be used as strong predictors in daily practice. In conclusion, PBSC collection on day 4 will not result in a successful harvest in most stem cell donors, however using a twice daily G‐CSF scheme increases the yield.     

The SMART‐COP score performs well for pneumonia risk stratification in Australia’s Tropical Northern Territory: a prospective cohort study

Objective To prospectively compare a modified pneumonia severity scoring system, SMARTACOP, with other severity scores in patients presenting with pneumonia to the emergency department (ED) of a tertiary referral hospital in tropical Australia. Methods We conducted a prospective observational study of adult patients presenting with radiologically confirmed pneumonia over a 12‐month period. The sensitivity of risk stratification scores were assessed against the need for intensive respiratory or vasopressor support (IRVS). Results There were 367 ED attendances for pneumonia of whom 77.1% were admitted to hospital, 10% required intensive respiratory or vasopressor support and 2.8% died. Mean age was 50.0 years, 52% were men and 59% were Indigenous. The sensitivity of a SMART‐COP score ≥3, a SMARTACOP score ≥3 and a pneumonia severity index (PSI) class ≥3 for predicting IRVS was 97%, 97% and 78% respectively. Conclusions We found no significant advantage of the SMARTACOP over the SMART‐COP score for the prediction of intensive respiratory or vasopressor support, but both scores significantly outperformed PSI. The SMART‐COP score should replace the PSI in tropical Australia and should be assessed in other tropical areas for pneumonia risk stratification in emergency departments.     

Acute liver failure

Acute liver failure (ALF) is a rare but life-threatening disease with varying aetiologies worldwide. Drug-induced liver injury, including paracetamol poisoning, is the main cause in Europe and the USA. Whereas in the developing world, viral hepatitis is most common. ALF is a multisystem illness that leads to development of hepatic encephalopathy, cerebral oedema, vasodilatory shock, coagulopathy, hypoglycaemia and multiple-organ failure. Early referral to a specialist liver unit is essential. The core principles of ALF management are to identify/treat the underlying cause, provide supportive care and treat any complications. Optimal management will allow time for spontaneous liver regeneration or liver transplantation, and result in improved survival rates. This article provides an overview of the key concepts in ALF diagnosis and management.