Dilip Kothari

Medication error in anaesthesia and critical care: A cause for concern

Medication error is a major cause of morbidity and mortality in medical profession, and anaesthesia and critical care are no exception to it. Man, medicine, machine and modus operandi are the main contributory factors to it. In this review, incidence, types, risk factors and preventive measures of the medication errors are discussed in detail.

Attenuation of circulatory and airway responses to endotracheal extubation in craniotomies for intracerebral space occupying lesions: Dexmedetomidine versus lignocaine.

Objectives: The objective of the study is to compare the effect of dexmedetomidine versus lignocaine in attenuation of circulatory and airway responses during endotracheal extubation in craniotomies for intracerebral space occupying lesions (ICSOL). Materials and Methods: A total of 50 patients of American Society of Anesthesiologists Grade I and II of either sex, aged 18-50 years undergoing craniotomies for non-vascular ICSOL under general anesthesia were divided into two groups according to drug received. Group D (n = 25) received dexmedetomidine (0.5 mcg/kg) whereas group L (n = 25) received lignocaine (1.5 mg/kg). Both the drugs were given 5 min before the extubation over a period of 60 s. Values for heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), were recorded just before (A0) and 1, 3, 5 (A1, A3, A5) min after the study drug administration, at extubation (E) and 1, 3, 5, 10, 15 min after extubation (E1, E3, E5, E10 and E15). Respiratory rate, oxygen saturation and airway responses like coughing, breath-holding, laryngospasm/bronchospasm were recorded only at extubation (E) and 1, 3, 5, 10, 15 min after extubation (E1, E3, E5, E10, E15). Quality of extubation was recorded with four point scale. After extubation all these patients were also observed for sedation by Ramsey sedation score. Results: Both groups showed a statistically significant increase (D < L) in HR, SBP and DBP during (E) and immediately after extubation (E1) (P < 0.05). Dexmedetomidine (72%) produced a higher degree of sedation (Grade 3) as compare with lignocaine (0%) and with no incidence of coughing or breath holding (P < 0.05). Conclusion: Single dose of dexmedetomidine (0.5 mcg/kg) given 5 min before extubation produced significant attenuation of circulatory and airway responses produced during extubation as compared to Lignocaine (1.5 mg/kg) in ICSOL.

Involvement of opioid and monoaminergic pain pathways in Aegle marmelos induced analgesia in mice.

Objective: To study analgesic activity and to evaluate the involvement of opioid and monoamines in the antinociceptive activity of methanol extract of leaves of Aegle marmelos. Materials and Methods: Analgesic activity of methanol extract (ME) of A. marmelos alone (75,150 and 300mg/kg orally) and in combination with morphine or venlafaxine (subanalgesic) were studied using tail flick test and acetic acid-induced writhing in mice. The effect of pre-treatment with opioid antagonist naltrexone 1mg/kg was also studied on antinociception induced due to ME. Result: ME produced a dose-dependent significant antinociceptive activity in the tail flick test and acetic acid-induced writhing in mice. (P<0.05) Administration of subanalgesic dose of ME with morphine or venlafaxine also resulted in significant (P<0.05) antinociceptive activity in both the pain models. Pre-treatment with naltrexone inhibited analgesic activity induced by ME alone and combination with morphine or venlafaxine. Conclusion: A.marmelos in induced antinociception is mediated through both opioid and monoaminergic pain pathways, suggest its possible use in chronic pain.

Colour-coded syringe labels: a modification to enhance patient safety.

Editor—Medication errors during anaesthesia are being reported in the literature from time to time. Misidentification of a drug because of look alike/sound alike drugs, syringe swap, confusing, inaccurate, or incomplete drug labels have been found responsible for these errors on many occasions. Up to 86–94% anaesthesiologists have agreed for the need of standardized drug labels to decrease the incidence of medication errors. Simple labels made from white adhesive tape or paper often fail to distinguish the different group of drugs, especially in critical situations. To prevent incidences of drug errors as a result of syringe and ampoule swap, Institute for Safe Medication Practices (ISMP) and American Society for Testing and Materials (ASTM) have recommended the standardized colour code for different anaesthetic drugs used in the operating theatre. Wassef and colleagues in a publication emphasized high speed and accuracy of drug administration because of colour coding in simulated high stress situations. On the other hand, there have been problems with the colour-coding system. Colour differentiation has not been proved to prevent medication error completely. The colour label identifies a drug category, but it does not necessarily identify a specific drug in that group. Mix-ups occur because of selection errors among products within a class of drugs having different strength and action. Availability of the limited number of absolute identifiable colours and to remember these multiple or complex colour-coding systems is another limitation to colour-coding of drugs. Further, between 5% and 8% of the general male population is colour blind, although no authentic study has been done on colour blindness among the medical and paramedical personnel in anaesthesiology. To minimize the impact of colour blindness among anaesthesiologists, ASTM has proposed specific guidelines for the maximum contrast between text and background as specified in section 6.3.1 of ASTM International standards D6398. In a letter published in the Anesthesia Patient Safety Foundation (APSF) newsletter, the author mentioned that anaesthesia providers may not read the label in critical situations because they only have time to recognize the colour and shape/size of the intended drug/syringe. Webster and Merry have recommended that colour coding should be used as a supplement to reading the label rather than substitute as the use of more than one cognitive cue (colour and text) always prevents the errors before they could occur. Anaesthesiologists in many countries such as the UK, Australia, New Zealand, the USA, South Africa, Canada, and Denmark have been using standardized colour-coded syringe labels. Different formats of texts including drug name, concentration, date, and time of preparation have been printed on these colour labels for differentiation and identification of drugs. In India, no specific guidelines are available for the use of colour-coded syringe labels but we are using labels provided by a pharmaceutical company (Neon Labs, India). We often find difficulty in the identification of a particular drug within a group, for example, morphine, meperidine, and fentanyl, because of common colour and font size. We made a few modifications in the present colour-coded syringe labels to overcome these problems and to enhance the safety as follows (Fig. 1):

Effect of nalbuphine and pentazocine on attenuation of hemodynamic changes during laryngoscopy and endotracheal intubation: A clinical study

Background: Narcotic drugs have been used to attenuate laryngoscopy and intubation induced circulatory responses, but are not always available due to tough narcotics laws. Nalbuphine a synthetic opioid, free from restrictions has been in use for post-operative pain relief. Hence, we decided to compare nalbuphine and pentazocine for attenuation of hemodynamic effects during larygoscopy and endotracheal intubation in a randomized, double-blind clinical study. Materials and Methods: A total of 60 patients (ASA I and II) of either sex, between 18 years and 50 years were given either nalbuphine 0.2 mg/kg (group N, n = 30) or pentazocine 0.5 mg/kg (group P, n = 30) 5 min before induction of general anesthesia. After, induction with thiopentone and endotracheal intubation with succinylcholine balanced anesthesia was maintained with O2:N2O, 0.2% halothane and non-depolarizing relaxants for surgical duration. Changes in heart rate (HR), systolic blood pressure (SBP), diastolic pressure, mean arterial pressure, and rate pressure product calculated by HR × SBP were recorded at various time intervals. Results: A non-significant fall (P > 0.05) up to 3 min and thereafter a significant rise (P < 0.05) in all the parameters were observed throughout the remaining study period with nalbuphine, whereas a continuous and significant (P < 0.05) rise in these parameters were observed with pentazocine. Maximum rise in both the group was observed immediately after larygoscopy and intubation and these started to return toward the basal values at the end of the study period, but remained above the initial values. (pentazocine > nalbuphine P = <0.01). Conclusion: Nalbuphine effectively reduces the tachycardia, hypertension, and cardiac workload associated with laryngoscopy and endotracheal intubation.