2009

Goh SH
Correspondence: Dr Goh Siang Hiong, siang_hiong_goh@cgh.com.sg

ABSTRACT
Bomb blast injuries are no longer confined to battlefields. With the ever present threat of terrorism, we should always be prepared for bomb blasts. Bomb blast injuries tend to affect air-containing organs more, as the blast wave tends to exert a shearing force on air-tissue interfaces. Commonly-injured organs include the tympanic membranes, the sinuses, the lungs and the bowel. Of these, blast lung injury is the most challenging to treat. The clinical picture is a mix of acute respiratory distress syndrome and air embolism, and the institution of positive pressure ventilation in the presence of low venous pressures could cause systemic arterial air embolism. The presence of a tympanic membrane perforation is not a reliable indicator of the presence of a blast injury in the other air-containing organs elsewhere. Radiological imaging of the head, chest and abdomen help with the early identification of blast lung injury, head injury, abdominal injury, eye and sinus injuries, as well as any penetration by foreign bodies. In addition, it must be borne in mind that bomb blasts could also be used to disperse radiological and chemical agents.

Keywords: blasts in enclosed spaces, bomb blast injuries, bowel perforation, high order explosives, mass casualty incidents, multiple fractures, pulmonary blast injury, tympanic membrane perforation
Singapore Med J 2009; 50(1): 101-106

Shobeiri E, Khalatbari MR, Taheri MS, Tofighirad N, Moharamzad Y
Correspondence: Dr Yashar Moharamzad, yasharpop@hotmail.com

ABSTRACT
Introduction This study aimed to compare the characteristics of magnetic resonance (MR) imaging in patients with low back pain (LBP) and those with sciatica.
Methods Clinical examination and MR imaging were performed on 100 sciatic and 100 LBP patients who were matched by age and gender. Different findings, including spinal canal stenosis, spondylolisthesis, the degree of disc herniation (bulge, protrusion, and extrusion) and nerve root compression, were documented. MR imaging findings were compared using the chi-square and Mann-Whitney U tests.
Results 11 percent of LBP patients and 37 percent of sciatic patients had spinal canal stenosis (p-value is less than 0.001). Spondylolisthesis was found in 12 percent of LBP patients and 14 percent of sciatic patients (p-value is 0.6). Disc extrusion was more common in patients with sciatica as compared to LBP patients at the L4–L5 level (29 percent vs. 4 percent; p-value is less than 0.001) and at the L5–S1 level (24 percent vs. 3 percent; p-value is less than 0.001). Nerve root compression was also more common in sciatic patients in the thecal sac (58 percent vs. 20 percent; p-value is less than 0.001) and in the lateral recess (73 percent vs. 19 percent; p-value is less than 0.001) than in LBP patients.
Conclusion Patients with sciatica were more likely to have spinal canal stenosis, disc extrusion (at L4–L5 and L5–S1 levels) and nerve root compression in the thecal sac and lateral recess.

Keywords: disc extrusion, low back pain, magnetic resonance imaging, nerve root compression, sciatica, spinal canal stenosis
Singapore Med J 2009; 50(1): 87-93

Saleem MM
Correspondence: Dr Mohammad M Saleem, mohomari@hotmail.com

ABSTRACT
Introduction Acquired oesophageal strictures are common in children. Treatment is either surgical or conservative by dilatations. String-guided dilators (SGD) are not well popularised. This is a report of the paediatric surgery experience at Jordan University Hospital on a group of 38 children, with emphasis on the use of SGD.
Methods Between January 1998 and January 2006, a total of 38 children (median age 3.2 years; range one month to ten years) with acquired oesophageal strictures were managed in the paediatric surgery unit. Main causes of strictures were corrosive strictures (18, 47.3 percent), post-oesophageal atresia repair (9, 23.6 percent) and post-hiatus hernia repair (4, 10.5 percent). SGD was used in 18 children, six following perforation and 12 classified as severe according to the established criteria. 14 were secondary to corrosive strictures.
Results There were 801 dilatation sessions with an average of 20.1 +/- 17.3 dilatation sessions per patient. Corrosive strictures were more severe, and required more dilatations per patient. The mean dilatation was 34.2 +/- 16.6 for corrosive strictures vs. 10.4 +/- 8.2 for non-corrosive strictures (p-value is less than 0.0001). 32 (84.2 percent) were successfully dilatated. Two are currently still under treatment and four failed conservative treatment after dilatation for one year. Two underwent oesophageal replacement and two refused surgery but continued to receive dilatation at 4–6 week intervals. SGD was used on 18 patients, six following perforation episodes. Two (5.3 percent) complications resulted in oesophageal perforations.
Conclusion Tucker’s dilators, with or without string, are safe, cost-effective and the use of string is a safeguard against perforations.

Keywords: acquired stricture, corrosive stricture, oesophageal stricture, string-guided dilator
Singapore Med J 2009; 50(1): 82-86

Evagelidis P, Paraskeva A, Petropoulos G, Staikou C, Fassoulaki A
Correspondence: Prof Argyro Fassoulaki, fassoula@aretaieio.uoa.gr

ABSTRACT
Introduction Exogenous melatonin has sedating and hypnotic actions. The present prospective double-blind randomised study investigated the effect of melatonin premedication on the induction of anaesthesia with sevoflurane.
Methods 71 women of reproductive age, scheduled for a hysteroscopy, were randomised into the melatonin or the control group. 30 minutes before the induction of anaesthesia, patients in the melatonin and control groups sublingually received 9 mg of melatonin or placebo, respectively. In the operating room, patients were attached to a standard monitor and bispectral index (BIS) monitor. Anaesthesia was induced with 8 percent sevoflurane in oxygen via an anaesthetic system primed with 8 percent sevoflurane. BIS values were recorded every 30 seconds,during the first 300 seconds of sevoflurane administration. Inspired and expired sevoflurane concentrations, heart rate and oxygen saturation were also recorded at the same time intervals. Noninvasive blood pressure was recorded before and after the completion of measurements.
Results BIS values (p-value is 0.725, F is 0.125, degrees of freedom [df] 1), inspired (p-value is 0.468, F is 0.535, df 1) and expired (p-value is 0.388, F is 0.756, df 1) sevoflurane concentrations, heart rate (p-values is 0.516, F is 0.427, df 1) and oxygen saturation (p-value is 0.401, F is 0.717, df 1), did not differ between the two groups, at any time point of measurement. Systolic blood pressure before (p-value is 0.131, t 1.530, df 67) and after measurement (p-value is 0.8288, t 0.218, df 54) as well as diastolic blood pressure before (p-value is 0.370, t 0.902, df 67) and after measurement (p-value is 0.764, t 0.302, df 54) did not differ between the two groups.
Conclusion Melatonin premedication under the present study design failed to enhance the induction of anaesthesia with sevoflurane.

Keywords: anaesthesia induction, bispectral index monitoring, central nervous system monitoring, exogenous melatonin, melatonin, sevoflurane
Singapore Med J 2009; 50(1): 78-81