Anatomy of sodium hypochlorite accidents involving facial ecchymosis—A review

Objectives

Root canal treatment forms an essential part of general dental practice. Sodium hypochlorite (NaOCl) is the most commonly used irrigant in endodontics due to its ability to dissolve organic soft tissues in the root canal system and its action as a potent antimicrobial agent. Although NaOCl accidents created by extrusion of the irrigant through root apices are relatively rare and are seldom life-threatening, they do create substantial morbidity when they occur.

Methods

To date, NaOCl accidents have only been published as isolated case reports. Although previous studies have attempted to summarise the symptoms involved in these case reports, there was no endeavour to analyse the distribution of soft tissue distribution in those reports. In this review, the anatomy of a classical NaOCl accident that involves facial swelling and ecchymosis is discussed.

Results

By summarising the facial manifestations presented in previous case reports, a novel hypothesis that involves intravenous infusion of extruded NaOCl into the facial vein via non-collapsible venous sinusoids within the cancellous bone is presented.

Conclusions

Understanding the mechanism involved in precipitating a classic NaOCl accident will enable the profession to make the best decision regarding the choice of irrigant delivery techniques in root canal débridement, and for manufacturers to design and improve their irrigation systems to achieve maximum safety and efficient cleanliness of the root canal system.     

API ionic liquids: probing the effect of counterion structure on physical form and lipid solubility

Lipid based formulations (LBFs) are extensively utilised as an enabling technology in drug delivery. The use of ionic liquids (ILs) or lipophilic salts (LS) in drug delivery has also garnered considerable interest due to unique solubility properties. Conversion of active pharmaceutical ingredients (API) to ILs by pairing with an appropriately lipophilic counterion has been shown to decrease melting point of the salt complex and improve solubility in LBFs. However, the relationship between the structure of the counterion, the physicochemical properties of the resulting salts and solubility in LBFs has not been systematically explored. This study investigates the relationship between alkyl sulfate counterion structure and melting temperature (T_m or T_g) in addition to LBF solubility, utilizing cinnarizine and lumefantrine as model weakly basic APIs. Three series of structurally diverse alkyl sulfate counterions were chosen to probe this relationship. Pairing cinnarizine and lumefantrine with a majority of these alkyl sulfate counterions resulted in a reduction in melting temperature and enhanced solubility in model medium chain and long chain LBFs. The chain length of the alkyl sulfate plays a crucial role in performance, and consistently branched alkyl sulfate counterions perform better than straight chain alkyl sulfate counterions, as predicted. Most interestingly, trends in counterion performance were found to be consistent across two APIs with disparate chemical structures. The findings from this study will facilitate the design of counterions which enhance solubility of ionisable drugs and unlock the potential to develop compounds previously restrained by poor solubility.

Structure/property relationship of API IL counterions and salt physicochemical properties are investigated, the results highlight the complex interplay involved.     

First impressions last… A survey of knowledge of first aid in burn-related injuries amongst hospital workers

Rationale

The administration of first aid in burns has been shown to have a significant influence on the ultimate severity of the burn. We wanted to assess in-hospital healthcare (HCW), and non-healthcare workers’ (nHCW) knowledge of first aid in burns.

Methods

A purpose-designed questionnaire, including information about previous attendance at a first aid course and four clinical scenarios of burns, was distributed to HCWs in the local hospitals and non-medical students in the Universities of Leeds and Sheffield.

Results

697 questionnaires were completed – 397 (57%) from HCW and 300 (43%) from nHCW. 59% of HCW had attended a first aid course, 68% of these courses included teaching on first aid in burns.HCW who had completed a first aid course generally did better than those who had not. Only 16% of HCW achieved correct answers in all questions compared to 30% nHCW.

Conclusions

We show that the knowledge of first aid in burns is relatively poor amongst HCW and that attendance at a burns first aid course improves knowledge (although perhaps not as much as one might hope). We recommend that the burns content of first aid courses be reviewed, and that there is a requirement for ALL hospital healthcare workers to undertake a first aid course, which includes appropriate burns first aid.     

Adjuvant Hepatic Intra-arterial Iodine-131-Lipiodol Following Curative Resection of Hepatocellular Carcinoma: A Prospective Randomized Trial

Background

The purpose of the present study was to determine whether intrahepatic injection of ¹³¹I-lipiodol (Lipiodol) is effective against recurrence of surgically resected hepatocellular carcinoma (HCC).

Methods

From June 2001 through March 2007, this nationwide multi-center prospective randomized controlled trial enrolled 103 patients 4–6 weeks after curative resection of HCC with complete recovery (52: Lipiodol, 51: Control). Follow-up was every 3 months for 1 year, then every 6 months. Primary and secondary endpoints were recurrence-free survival (RFS) and overall survival (OS), respectively, both of which were evaluated by the Kaplan–Meier technique and summarized by the hazard ratio (HR). The design was based on information obtained from a similar trial that had been conducted in Hong Kong.

Results

The Lipiodol group showed a small, and nonsignificant, improvement over control in RFS (HR = 0.75; 95 % confidence interval [95 % CI] 0.46–1.23; p = 0.25) and OS (HR = 0.88; 95 % CI 0.51–1.51; p = 0.64). Only two serious adverse events were reported, both with hypothyroidism caused by ¹³¹I-lipiodol and hepatic artery dissection during angiography.

Conclusions

The randomized trial provides insufficient evidence to recommend the routine use of ¹³¹I-lipiodol in these patients.