In the presence of wound infection from snakebite injury in Hong Kong, first line empirical antibiotics include amoxicillin/clavulanic acid plus levofloxacin. Prophylactic antibiotics may be considered in selected cases of Chinese cobra (N. atra) bite, otherwise prophylactic antibiotics are not recommended in snakebite unless tissue necrosis is present.

There is clear room for improvement in the knowledge base and confidence level of physicians treating snakebites in Hong Kong. Key components of management, such as ASV choice, indications, dosing, and clinical endpoints for administration, were sources of confusion to the participants in this study. The results demonstrate the need for a locally developed and widely distributed snakebite management protocol.

Introduction. Most cases of methemoglobinemia result from exposure to certain medications and chemicals such as nitrates, nitrites, aniline, dapsone, phenazopyridine, benzocaine, and chlorates which oxidize the iron from the ferrous state. Intoxication with zopiclone is expected to produce drowsiness, confusion and coma but not methemoglobinemia. We report two cases of zopiclone overdose with methemoglobinemia. Case Reports. Case one: A 43-year-old woman presented to the emergency department two hours after ingesting 100 tablets of 7.5 mg zopiclone. Her initial vital signs, physical examination, chest x-ray, and electrocardiogram were normal. Two hours post-ingestion her methemoglobin level was 9.8%; 14 hours post-arrival she showed cyanosis of the lips and extremities and dyspnea after walking. The blood sample 16 hours post-ingestion was dark brown in color and the methemoglobin was 23.8%. Shortly after the second of two doses of methylene blue (1 mg/kg each) her methemoglobin was 3.6%. Case two: A 30-year-old woman came to the emergency department 50 hours after ingesting 150 to 200 tablets of 7.5 mg zopiclone. Her vital signs and physical examination were normal. Her methemoglobin level was 5.2% at 52 hours post-ingestion and it peaked at 10.4% one hour later. She recovered following symptomatic care. Discussion and Conclusions. Methemoglobinemia has not previously been reported following acute zopiclone overdose. In our patients, there were no identifiable alternative causes explaining the methemoglobinemia and zopiclone was confirmed in both patients by laboratory analysis. These two cases suggest that zopiclone overdose is capable of producing delayed methemoglobinemia, which may be related to formation of a sufficient quantity of the N-oxide metabolite.

The combined use of a lightwand and the intubating laryngeal mask airway (ILMA) was compared with the use of the ILMA alone to determine whether the combination was a more efficient method of endotracheal intubation. One hundred healthy patients were randomly assigned to two groups. After induction of anaesthesia, Group A patients were intubated blindly through the ILMA while in Group B, intubation was guided by a lightwand. A sequence of standard manoeuvres was followed if attempts at intubation failed. The number of manoeuvres used, the time taken for successful intubation and complications associated with intubation were recorded. Intubations were successful in all patients, but the mean endotracheal intubation time was longer in Group A than in Group B (38.3±10.4 s versus 26.4±9.1 s, P<0.001). The number of patients who needed one or more manoeuvres was significantly higher in Group A than in Group B (76% versus 42%, P=0.001). We conclude that the lightwand is a useful adjunct in endotracheal intubation through an ILMA.

We conducted a crossover randomised study to evaluate the performance of a novel optical stylet, the InnoScope, for tracheal intubation in simulated normal and difficult airways. Twenty-five anaesthetists attempted tracheal intubation on a SimMan 3G simulator using the InnoScope first followed by the Macintosh laryngoscope or vice versa. Three airway scenarios were tested: (1) normal airway; (2) difficult airway with swollen pharynx; and (3) limited neck movement. In each scenario, the laryngeal view, duration of and success rate for tracheal intubation were recorded. Compared with the Macintosh laryngoscope, the use of InnoScope increased the percentage of glottic opening seen by 17% in normal airway, 23% in the difficult airway and 32% with limited neck movement, p < 0.01. Despite this better laryngeal view, successful tracheal intubation achieved with the InnoScope (88.0%) was lower than that for the Macintosh laryngoscope (98.7%), p = 0.008. Using the InnoScope, tracheal intubation during the first attempt was only successful in 48% of cases with difficult airway. In this scenario, the median (interquartile range [range]) duration of tracheal intubation was significantly longer with [corrected] InnoScope compared with the Macintosh laryngoscope, (70 (19-120 [15-120)] s vs 30 [21-58 (15-120)] s, [corrected] p = 0.01. We conclude that an improved laryngeal view with the use of the InnoScope did not translate into better conditions for tracheal intubation.